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                                                                                FM 5-125
                                                                                      C1

Change 1                                                                       Headquarters
                                                                    Department of the Army
                                                           Washington, DC, 23 February 2001



            Rigging Techniques, Procedures,
                    and Applications
1.   Change FM 5-125, 3 October 1995, as follows:

     Remove Old Pages                               Insert New Pages

     i through iv                                   i through iv
     vii and viii                                   vii and viii
     1-15 through 1-20                              1-15 through 1-21
     2-37 through 2-40                              2-37 through 2-40

2.   A bar ( ) marks new or changed material.

3.   File this transmittal sheet in front of the publication.

DISTRIBUTION RESTRICTION: Approved for public release; distribution is unlimited.

                                                    ERIC K. SHINSEKI
                                                  General, United States Army
                                                         Chief of Staff

Official:


     JOEL B. HUDSON
Adiministrative Assistant to the
   Secretary of the Army
                 0100405

DISTRIBUTION:

Active Army, Army National Guard, and US Army Reserve: To be distributed in accordance
with the initial distribution number 115426, requirements for FM 5-125.
                                                                                                                           *FM 5-125

Field Manual                                                                                         Headquarters
No. 5-125                                                                                 Department of the Army
                                                                                    Washington, DC, 3 October 1995




                       Rigging Techniques,
                   Procedures, and Applications
Contents

                                                                                                                                   Page

LIST OF FIGURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii
LIST OF TABLES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xv
PREFACE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xvii
Chapter 1. Rope
  Section I. Fiber Rope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
    Types of Fibers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
       Vegetable Fibers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
       Synthetic Fibers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
    Characteristics of Fiber Rope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
       Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
       Weight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
       Strength . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
    Care of Fiber Rope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
    Handling of Fiber Rope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5
    Inspection of Fiber Rope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
  Section II. Wire Rope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
    Types of Wire-Rope Cores. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7
       Fiber-Rope Cores . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7
       Independent Wire-Rope Cores . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7
       Wire-Strand Cores . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7




DISTRIBUTION RESTRICTION: Approved for public release; distribution is unlimited.
*This manual supersedes TM 5-725, 3 October 1968.



                                                                     i
C1, 5-125
FM  FM 5-125




                                                                                                                                       Page
        Classification of Wire Rope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7
           Wire and Strand Combinations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7
           Lay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7
        Characteristics of Wire Rope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-9
           Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-9
           Weight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-9
           Strength . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-9
        Care of Wire Rope. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10
           Reversing or Cutting Back Ends. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11
           Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11
           Lubricating. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11
           Storing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11
        Handling of Wire Rope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11
           Kinking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-12
           Coiling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-12
           Unreeling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-12
           Seizing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-12
           Welding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-14
           Cutting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-14
           Drums and Sheaves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-15
        Inspection of Wire Rope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-20
           Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-20
           Causes of Failure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-21


Chapter 2. Knots, Splices, Attachments, and Ladders
  Section I. Knots, Hitches, and Lashings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
    Knots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
       Knots at the End of Rope. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4
       Knots for Joining Two Ropes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5
       Knots for Making Loops . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6
       Knots for Tightening a Rope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12
       Knots for Wire Rope. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-13
    Hitches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-17
       Half Hitch. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-17
       Two Half Hitches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-17
       Round Turn and Two Half Hitches. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-18
       Timber Hitch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-18
       Timber Hitch and Half Hitch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-18
       Clove Hitch. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-18


                                                                     ii
                                                                                                                   C1, FM 5-125
                                                                                                                       FM 5-125




                                                                                                                               Page
     Rolling Hitch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-18
     Telegraph Hitch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-19
     Mooring Hitch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-19
     Scaffold Hitch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-19
     Blackwall Hitch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-19
     Harness Hitch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-22
     Girth Hitch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-22
     Sheepshank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-23
     Fisherman's Bend . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-23
  Lashings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-24
     Square Lashing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-24
     Shears Lashing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-24
     Block Lashing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-26
Section II. Splices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-26
  Fiber-Rope Splices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-26
     Short Splice                                                                                                              2-26
     Eye or Side Splice. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-26
     Long Splice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-28
     Crown or Back Splice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-28
  Wire-Rope Splices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-31
     Short Splice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-31
     Eye or Side Splice. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-31
     Long Splice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-32
Section III. Attachments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-34
  End Fittings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-35
     Clips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-35
     Clamps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-37
  Wedge Socket . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-37
  Basket-Socket End Fitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-37
     Poured Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-37
  Stanchions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-40
Section IV. Rope Ladders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-41
  Hanging Ladders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-41
     Wire-Rope Ladders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-41
     Fiber-Rope Ladders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-43
  Standoff Ladders. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-45




                                                               iii
FM 5-125




                                                                                                                                 Page
Chapter 3. Hoists
  Section I. Chains and Hooks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
    Chains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
       Strength of Chains. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
       Care of Chains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
    Hooks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
       Strength of Hooks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
       Mousing of Hooks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
    Inspection of Chains and Hooks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4
  Section II. Slings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5
    Types of Slings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5
       Endless Slings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5
       Single Slings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6
       Combination Slings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7
    Pallets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-8
    Spreaders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-8
    Stresses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-9
    Inspecting and Cushioning Slings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-9
  Section III. Blocks and Tackle Systems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-14
    Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-14
       Types of Blocks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-14
       Reeving of Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-16
    Tackle Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-18
       Simple Tackle Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-18
       Compound Tackle Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-18
       Friction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-20
  Section IV. Chain Hoists and Winches. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-22
    Chain Hoists . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-22
       Types of Chain Hoists . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-22
       Load Capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-23
    Winches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-24
       Ground Angle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-24
       Fleet Angle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-24
       Spanish Windlass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-25




                                                                    iv
                                                                                                                  C1, FM 5-125




                                    List of Figures

                                                                                                                          Page
Figure 1-1.    Cordage of rope construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . l-2
Figure 1-2.    Uncoiling and coiling rope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5
Figure 1-3.    Elements of wire-rope construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
Figure 1-4.    Arrangement of strands in wire rope . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8
Figure 1-5.    Wire-rope lays. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8
Figure 1-6.    Measuring wire rope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-9
Figure 1-7.    Kinking in wire rope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-12
Figure 1-8.    Unreeling wire rope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-13
Figure 1-9.    Uncoiling wire rope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-13
Figure 1-10.   Seizing wire rope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-14
Figure 1-11.   Wire-rope cutter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-15
Figure 1-12.   Avoiding reverse bends in wire rope . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-17
Figure 1-13.   Spooling wire rope from reel to drum . . . . . . . . . . . . . . . . . . . . . . . . . . 1-17
Figure 1-14.   Determining starting flange of wire rope . . . . . . . . . . . . . . . . . . . . . . 1-18
Figure 1-15.   Winding wire-rope layers on a drum. . . . . . . . . . . . . . . . . . . . . . . . . . . 1-19
Figure 1-16.   Lay length. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-20
Figure 1-17.   Unserviceable wire rope. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-21
Figure 2-1.    Elements of knots, bends, and hitches . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
Figure 2-2.    Whipping the end of a rope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
Figure 2-3.    Overhand knot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4
Figure 2-4.    Figure-eight knot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4
Figure 2-5.    Wall knot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5
Figure 2-6.    Crown on a wall knot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6
Figure 2-7.    Square knot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7
Figure 2-8.    Single sheet bend . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7
Figure 2-9.    Double sheet bend . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
Figure 2-10.   Carrick bend . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
Figure 2-11.   Bowline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-9
Figure 2-12.   Double bowline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-10


                                                            vii
FM 5-125




                                                                                                                          Page
Figure 2-13. Running bowline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-10
Figure 2-14. Bowline on a bight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11
Figure 2-15. Spanish bowline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12
Figure 2-16. French bowline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12
Figure 2-17. Speir knot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-13
Figure 2-18. Cat's-paw. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-13
Figure 2-19. Figure eight with an extra turn. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-14
Figure 2-20. Butterfly knot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-14
Figure 2-21. Baker bowline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-15
Figure 2-22. Half hitches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-17
Figure 2-23. Round turn and two half hitches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-18
Figure 2-24. Timber hitch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-18
Figure 2-25. Timber hitch and half hitch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-18
Figure 2-26. Clove hitch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-19
Figure 2-27. Rolling hitch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-20
Figure 2-28. Telegraph hitch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-20
Figure 2-29. Mooring hitch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-21
Figure 2-30. Scaffold hitch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-21
Figure 2-31. Blackwall hitch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-22
Figure 2-32. Harness hitch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-22
Figure 2-33. Girth hitch. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-23
Figure 2-34. Sheepshank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-23
Figure 2-35. Fisherman's bend . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-24
Figure 2-36. Square lashing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-25
Figure 2-37. Shears lashing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-25
Figure 2-38. Block lashing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-26
Figure 2-39. Renewing rope strands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-27
Figure 2-40. Short splice for fiber rope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-27
Figure 2-41. Eye or side splice for fiber rope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-28
Figure 2-42. Long splice for fiber rope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-29
Figure 2-43. Crown or back splice for fiber rope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-30
Figure 2-44. Tools for wire splicing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-32
Figure 2-45. Tucking wire-rope strands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-32
Figure 2-46. Eye splice with thimble for wire rope . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-33
Figure 2-47. Hasty eye splice for wire rope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-33


                                                                viii
                                                                                    FM 5-125




                    Wire rope
                    cutter




                                                                      Blade

         Seizings




                                Figure 1-11. Wire-rope cutter

the two central seizings. Push the blade         other in addition to bending. Keep this
down against the wire rope and strike the        bending and moving of wires to a minimum
top of the blade sharply with a sledge ham-      to reduce wear. If the sheave or drum
mer several times. Use the bolt clippers on      diameter is sufficiently large, the loss of
wire rope of fairly small diameter; however,     strength due to bending wire rope around
use an oxyacetylene torch on wire rope of        it will be about 5 or 6 percent. In all cases,
any diameter. The hacksaw and cold chisel        keep the speed of the rope over the sheaves
are slower methods of cutting.                   or drum as slow as is consistent with effi-
                                                 cient work to decrease wear on the rope. It
          DRUMS AND SHEAVES                      is impossible to give an absolute minimum
The size and location of the sheaves and         size for each sheave or drum, since a num-
drums about which wire rope operates and         ber of factors enter into this decision. How-
the speed with which the rope passes over        ever, Table 1-4, page 1-16 , shows the
the sheaves have a definite effect on the        minimum recommended sheave and drum
rope's strength and service life.                diameters for several wire-rope sizes. The
                                                 sheave diameter always should be as large
                                                 as possible and, except for very flexible
                        Size
                                                 rope, never less than 20 times the wire-
Each time wire rope is bent, the individual      rope dia meter. This figure has been
strands must move with respect to each           adopted widely.



                                                                                  Rope    1-15
C1,5-125
FM  FM 5-125



                Table 1-4. Minimum tread diameter of drums and sheaves


                 Rope                            Minimum Tread Diameter for Given Rope
               Diameter                                 Construction* (inches)
               (inches)
                                          6x7                   6 x 19               6 x 37        8 x 19

                    1/4                  10 1/2                     8 1/2                           6 1/2

                    3/8                  15 3/4                 12 3/4               6 3/4          9 3/4

                    1/2                    21                        17                9             13

                    5/8                  26 1/4                 21 1/4               11 1/4        16 1/4

                    3/4                  31 1/2                 25 1/2               13 1/2        19 1/2

                    7/8                  36 3/4                 29 3/4               15 3/4        22 3/4

                     1                     42                        34               18             26

                   1 1/8                 47 1/4                 38 1/4               20 1/4        29 1/4

                   1 1/4                 52 1/2                 42 1/2               22 1/2        32 1/2

                   1 1/2                   63                        51               27             39
              *Rope construction is strands and wires per strand.




                         Location                                           in smooth layers. Overlapping results in
                                                                            binding, causing snatches on the line when
You should reeve the drums, sheaves, and
blocks used with wire rope and place them                                   the rope is unwound. To produce smooth lay-
in a manner to avoid reverse bends when-                                    ers, start the rope against one flange of the
ever possible (see Figure 1-12). A reverse                                  drum and keep tension on the line while
bend occurs when rope bends in one direc-                                   winding. Start the rope against the right or
tion around one block, drum, or sheave and                                  left flange as necessary to match the direc-
bends in the opposite direction around the                                  tion of winding, so that when it is rewound
next. This causes the individual wires and                                  on the drum, the rope will curve in t h e
strands to do an unnecessary amount of                                      same manner as when it left the reel (see
shifting, which increases wear. Where you                                   Figure 1-13). A convenient method for deter-
must use a reverse bend, the block, sheave,                                 mining the proper flange of the drum for
or drum causing the reversal should be of                                   starting the rope is known as the hand rule
larger diameter t h a n o r d i n a r i l y u s e d .
                                                                            (see Figure 1-14, page 1-18 ). The extended
Space the bend as far apart as possible so
there will be more time allowed between                                     index finger in this figure points at the on-
the bending motions.                                                        winding rope. The turns of the rope are
                                                                            wound on the drum close together to prevent
                                                                            the possibility of crushing and abrasion of
                         Winding                                            the rope while it is winding and to prevent
Do not overlap wire-rope turns when wind-                                   binding or snatching when it is unwound. If
ing them on the drum of a winch; wrap them                                  ne ce ssa r y, use a wood stick to force the



1-16   Rope
                                                    C1, FM
                                                         FM5-125
                                                            5-125


                    Block


 Drum                              Drum




                                                     Block




                1                             2

                            INCORRECT


                     Block
                                    Drum
  Drum




                                                     Block


                3                             4
                             CORRECT

Figure 1-12. Avoiding reverse bends in wire rope


         Reel

                                   Drum




         Reel

                                       Drum




Figure 1-13. Spooling wire rope from reel to drum




                                                      Rope   1-17
C1,5-125
FM FM 5-125




                         For right-lay rope                                       For left-lay rope
                         (use right hand)                                         (use left hand)




    For overwind on drum--          For underwind on drum--        For overwind on drum--        For underwind on drum--
       The palm is down,              The palm is up, facing        The palm is down,            The palm is up, facing
        facing the drum.                the drum.                      facing the drum.              the drum.
       The index finger points        The index finger points       The index finger points      The index finger points
        at on-winding rope.             at on-winding rope.            at on-winding rope.           at on-winding rope.
       The index finger must          The index finger must         The index finger must        The index finger must
        be closest to the               be closest to the              be closest to the             be closest to the
        left-side flange.               right-side flange.             right-side flange.            left-side flange.
       The wind of the rope           The wind of the rope          The wind of the rope         The wind of the rope
        must be from left to            must be from right to          must be from right to         must be from left to
        right along the drum.           left along the drum.           left along the drum.          right along the drum.



                                  If a smooth-face drum has been cut or scored by an old rope,
                                  the methods shown may not apply.



                      Figure 1-14. Determining starting flange of wire rope


turns closer together. Striking the wire with                     layer; however, cross each turn of the rope
a hammer or other metal object damages                            in the second layer over two turns of the
the individual wires in the rope. If possi-                       first layer (see Figure 1-15). Wind the third
b l e , w i n d o n l y a si n g l e l a y e r o f w i r e        layer in the grooves of the second layer;
rope on the drum. Where it is necessary to                        however, each turn of the rope will cross
wind additional layers, wind them so as                           over two turns of the second layer.
to eliminate the binding. Wind the second
layer of turns over the first layer by placing
the wire in the grooves formed by the first




1-18    Rope
                                                                                   C1, FM
                                                                                       FM 5-125
                                                                                          5-125




                                                   Cross-over two turns
 Cross-over to                                      of the second layer
second groove




      Turn back and first          Five turns on            Starting third layer
        cross-over for             second layer
         second layer


                 Figure 1-15. Winding wire-rope layers on a drum




                                                                                   Rope   1-19
C1, 5-125
FM  FM 5-125




                              INSPECTION OF WIRE ROPE

Inspect wire rope frequently. Replace            Replace the wire rope when 1.25 per-
frayed, kinked, worn, or corroded rope. The       cent of the total rope wires are broken
frequency of inspection is determined by          in one strand in one lay.
the amount of use. A rope that is used 1 or
2 hours a week requires less frequent inspec-    Replace wire rope with 200 or more
tion than one that is used 24 hours a day.        wires (6 x 37 class) when the surface
                                                  wires show flat wear spots equal in
                                                  width to 80 percent of the diameter of
               PROCEDURES                         the wires. On wire rope with larger
Carefully inspect the weak points in rope         and fewer total wires (6 x 7, 7 x 7, 7 x
and the points where the greatest stress          19), replace it when the flat wear spot
occurs. Worn spots will show up as shiny          width is 50 percent of the wire diame-
flattened spots on the wires.                     ter.

Inspect broken wires to determine whether        Replace the wire if it is kinked or if
it is a single broken wire or several wires.      there is evidence of a popped core or
Rope is unsafe if--                               broken wire strands protruding from
                                                  the core strand. See Figure 1-17.
    Individual wires are broken next to
     one another, causing unequal load dis-      Replace the wire rope if there is evi-
     tribution at this point.                     dence of an electrical arc strike (or
                                                  other thermal damage) or crushing
    Replace the wire rope when 2.5 per-          damage.
     cent of the total rope wires are broken
     in the length of one lay, which is the      Replace the wire rope if there is evi-
     length along the rope that a strand          dence of "birdcage" damage due to
     makes one complete spiral around the         shock unloading. See Figure 1-17.
     rope core. See Figure 1-16.




                   One lay


         Figure 1-16. Lay length




1-20   Rope
                                                                         C1, FM
                                                                             FM 5-125
                                                                                5-125




                      Popped core




                      Birdcage




                         Figure 1-17. Unserviceable wire rope


          CAUSES OF FAILURE                     Overwinding or crosswinding it on
                                                 drums.
Wire rope failure is commonly caused by--
                                                Operating it over drums and sheaves
   Sizing, constructing, or grading it
                                                 that are out of alignment.
    incorrectly.
                                                Permitting it to jump sheaves.
   Allowing it to drag over obstacles.
                                                Subjecting it to moisture or acid
   Lubricating it improperly.
                                                 fumes.
   Operating it over drums and sheaves
                                                Permitting it to untwist.
    of inadequate size.
                                                Kinking.




                                                                             Rope   1-21
                                                                                     C1,FM
                                                                                         FM5-125
                                                                                            5-125




after applying the working load and at fre-
quent intervals thereafter. Retightening is
necessary to compensate for the decrease in
rope diameter that occurs when the strands
adjust to the lengthwise strain caused by the
load. Position the clips so that they are
immediately accessible for inspection and
maintenance.

                   CLAMPS
A wire clamp can be used with or without a
thimble to make an eye in wire rope (see Fig-
ure 2-51). Ordinarily, use a clamp to make
an eye without a thimble. It has about 90
percent of the strength of the rope. Tighten
the two end collars with wrenches to force
the clamp to a good snug fit. This crushes
the pieces of rope firmly against each other.
                                                        Figure 2-51. Wire-rope clamps


                                       WEDGE SOCKET
Use a wedge-socket end fitting when it is          tapered socket. The loop of wire rope must
necessary to change the fitting at frequent        be inserted in the wedge socket so that the
intervals (see Figure 2-52, page 2-38). The        standing part of the wire rope will form a
efficiency is about two-thirds of the strength     nearly direct line to the clevis pin of the fit-
of the rope. It is made in two parts. The          ting. A properly installed wedge-socket con-
socket itself has a tapered opening for the        nection will tighten when a strain is placed
wire rope and a small wedge to go into this        on the wire rope.

                               BASKET-SOCKET END FITTING
The basket-socket end fittings include closed                   POURED METHOD
sockets, open sockets, and bridge sockets
                                                   The poured basket socket is the most satis-
(see Figure 2-53, page 2-38). This socket is
                                                   factory method in use (see Figure 2-54, page
ordinarily attached to the end of the rope
                                                   2-39 ). If the socketing is properly done, a
with molten zinc and is a permanent end
                                                   wire rope, when tested to destruction, will
rifting. If this fitting is properly made up, it
is as strong as the rope itself. In all cases,     break before it will pull out from the socket.
the wire rope should lead from the socket in
line with the axis of the socket.

                  WARNING
  Never use babbitt, lead, or dry method to
  attach a basket socket end fitting.




                                             Knots, Splices, Attachments, and Ladders         2-37
C1,5-125
FM  FM 5-125



Live end                                                                                       Add clamp and
                                                             Live end                          short cable
                   Dead                                                                        splice.
                   end



                                             Dead
                     6 to 9 times            end
                     diameter
                                                                 Entering
                                                                 wrong side


                                             Not long
                                             enough




                                                                                 READY-TO-USE


                                                                                      CAUTION
           RIGHT                                                        Never clamp the live end to the dead
                                                        WRONG           end. Add the clamp and the short cable
                                                                        splice to the dead end as shown above.


                                         Figure 2-52. Wedge socket




                                    Wedge               Bridge             Open                Closed
                                    socket              socket             socket              socket



                                Figure 2-53. Basket-socket end fittings




2-38   Knots, Splices, Attachments, and Ladders
                                                                   C1,FM
                                                                       FM5-125
                                                                          5-125




                      Spread the wires in
                      each strand.




       Unlay the strands equal
       to the length of the
       socket.



       1




                                      Pour in molten
                                      zinc.




   Pull the rope
   into the socket.                         Place putty or
                                            clay here.




   2                                                   3




Figure 2-54. Attaching basket sockets by pouring




                                 Knots, Splices, Attachments, and Ladders   2-39
C1, FM 5-125
FM 5-125




               DRY METHOD                       method (see Figure 2-55). The strength of
                                                the connection must be assumed to be
The dry method should be used only when         reduced to about one-sixth of the strength
facilities are not available for the poured     of a poured zinc connection.

                                      STANCHIONS
The standard pipe stanchion is made up of a     modifying it, for a suspended walkway
1-inch diameter pipe (see Figure 2-56). Each    that uses two wire ropes on each side.
stanchion is 40 inches long. Two 3/4-inch       However, for handlines, remove or leave
wire-rope clips are fastened through holes in   off the lower wire-rope clip. For more infor-
the pipe with the centers of the clips 36       mation on types and uses of stanchions,
inches apart. Use this stanchion, without       see TM 5-270.




2-40   Knots, Splices, Attachments, and Ladders
                                                                         *FM 5-125

Field Manual                                                       Headquarters
No. 5-125                                               Department of the Army
                                                  Washington, DC, 3 October 1995




DISTRIBUTION RESTRICTION: Approved for public release; distribution is unlimited.
*This publication supersedes TM 5-725, 3 October 1968.


                                         i
FM 5-125




           ii
      FM 5-125




iii
FM 5-125




           iv
    FM 5-125




v
FM 5-125




           vi
                            FM 5-125




List   of         Figures




            vii
FM 5-125




           viii
     FM 5-125




ix
FM 5-125




           x
     FM 5-125




xi
FM 5-125




           List   of     Tables




                   xii
                                                                                         FM 5-125




                                       Preface



This manual is a guide and basic reference for personnel whose duties require the use of rig-
ging. It is intended for use in training and as a reference manual for field operations. It cov-
ers the types of rigging and the application of fiber rope, wire rope, and chains used in
various combinations to raise or move heavy loads. It includes basic instructions on knots,
hitches, splices, lashing, and tackle systems. Safety precautions and requirements for the
various operations are listed, as well as rules of thumb for rapid safe-load calculations.




The material contained herein is applicable to both nuclear and nonnuclear warfare.

The proponent for this publication is Headquarters (HQ), United States (US) Army Train-
ing and Doctrine Command (TRADOC). Users of this manual are encouraged to submit rec-
ommended changes or comments on Department of the Army (DA) Form 2028 and forward
them to: Commandant, US Army Engineer School, ATTN: ATSE-T-PD-P, Fort Leonard
Wood, Missouri 65473-6500.

Unless otherwise stated, masculine nouns and pronouns do not refer exclusively to men.




                                              xiii
                                                                                    FM 5-125




                                     CHAPTER           1


                                           Rope


                                 Section 1. Fiber Rope
In the fabrication of fiber rope, a number       in the opposite direction puts the rope in
of fibers of various plants are twisted          balance and prevents its elements from
together to form yarns. These yarns are          unlaying when a load is suspended on it.
then twisted together in the opposite direc-     The principal type of fiber rope is the
tion of the fibers to form strands (see Figure   three-strand, right lay, in which three
1-1, page 1-2). The strands are twisted in       strands are twisted in a right-hand direc-
the opposite direction of the yarns to form      tion. Four-strand ropes, which are also
the completed rope. The direction of twist of    available, are slightly heavier but are
each element of the rope is known as the         weaker than three-strand ropes of the
"lay" of that element. Twisting each element     same diameter.

                                    TYPES OF FIBERS
The term cordage is applied collectively to                         Manila
ropes and twines made by twisting together       This is a strong fiber that comes from the
vegetable or synthetic fibers.                   leaf stems of the stalk of the abaca plant,
                                                 which belongs to the banana family. The
            VEGETABLE FIBERS                     fibers vary in length from 1.2 to 4.5 meters
The principal vegetable fibers are abaca         (4 to 15 feet) in the natural states. The
(known as Manila), sisalana and henequen         quality of the fiber and its length give
(both known as sisal), hemp, and some-           Manila rope relatively high elasticity,
times coir, cotton, and jute. The last three     strength, and resistance to wear and dete-
are relatively unimportant in the heavy          rioration. The manufacturer treats the
                                                 rope with chemicals to make it more mil-
cordage field.
                                                 dew resistant, which increases the rope's
Abaca, sisalana, and henequen are classi-        quality. Manila rope is generally the stan-
fied as hard fibers. The comparative             dard item of issue because of its quality
strengths of the vegetable fibers, consider-     and relative strength.
ing abaca as 100, are as follows:
    Sisalana                          80                            Sisal
    Henequen                          65         Sisal rope is made from two tropical
                                                 plants, sisalana and henequen, that pro-
    Hemp                             100         duce fibers 0.6 to 1.2 meters (2 to 4 feet)


                                                                                  Rope 1-1
FM 5-125




long. Sisalana produces the stronger fibers      yarn. Since hemp absorbs much better
of the two plants, so the rope is known as       than the hard fibers, these fittings are
sisal. Sisal rope is about 80 percent as         invariably tarred to make them more
strong as high quality Manila rope and can       water-resistant. Tarred hemp has about
be easily obtained. It withstands exposure       80 percent of the strength of untarred
to sea water very well and is often used for     hemp. Of these tarred fittings, marline is
this reason.                                     the standard item of issue.

                     Hemp                                      Coir and Cotton
This tall plant is cultivated in many parts of   Coir rope is made from the fiber of coconut
the world and provides useful fibers for         husks. It is a very elastic, rough rope
making rope and cloth. Hemp was used             about one-fourth the strength of hemp but
extensively before the introduction of           light enough to float on water. Cotton
Manila, but its principal use today is in fit-   makes a very smooth white rope that with-
tings, such as ratline, marline, and spun        stands much bending and running. These


1-2 Rope
                                                                                   FM 5-125



two types of rope are not widely used in the                SYNTHETIC FIBERS
military; however, cotton is used in some
cases for very small lines.                      The principal synthetic fiber used for rope
                                                 is nylon. It has a tensile strength nearly
                                                 three times that of Manila. The advantage
                      Jute                       of using nylon rope is that it is waterproof
Jute is the glossy fiber of either of two East   and has the ability to stretch, absorb
Indian plants of the linden family used          shocks, and resume normal length. It also
chiefly for sacking, burlap, and cheaper vari-   resists abrasion, rot, decay, and fungus
eties of twine and rope.                         growth.


                      CHARACTERISTICS OF FIBER ROPE
Fiber rope is characterized by its size, the SWC of rope, divide the BS by a factor
weight, and strength.                    of safety (FS):
                                                    SWC = BS/FS
                     SIZE
                                                 A new l-inch diameter, Number 1 Manila
Fiber rope is designated by diameter up to       rope has a BS of 9,000 pounds (see
5/8 inch, then it is designated by circumfer-    Table 1-1). To determine the rope's SWC,
ence up to 12 inches or more. For this rea-      divide its BS (9,000 pounds) by a minimum
son, most tables give both the diameter and      standard FS of 4. The result is a SWC of
circumference of fiber rope.                     2,250 pounds. This means that you can
                                                 safely apply 2,250 pounds of tension to the
                                                 new l-inch diameter, Number 1 Manila
                  WEIGHT                         rope in normal use. Always use a FS
The weight of rope varies with use, weather      because the BS of rope becomes reduced
conditions, added preservatives, and other       after use and exposure to weather condi-
factors. Table 1-1, page 1-4, lists the weight   tions. In addition, a FS is required because
of new fiber rope.                               of shock loading, knots, sharp bends, and
                                                 other stresses that rope may have to with-
                                                 stand during its use. Some of these
                 STRENGTH                        stresses reduce the strength of rope as
Table 1-1 lists some of the properties of        much as 50 percent. If tables are not avail-
Manila and sisal rope, including the break-      able, you can closely approximate the SWC
ing strength (B S), which is the greatest        by a rule of thumb. The rule of thumb for
                                                 the SWC, in tons, for fiber rope is equal to
stress that a material is capable of with-       the square of the rope diameter (D) in
standing without rupture. The table shows        inches:
that the minimum BS is considerably                          2
greater than the safe load or the safe work-        SWC = D
ing capacity (SWC). This is the maximum          The SWC, in tons, of a l/2-inch diameter
load that can safely be applied to a particu-    fiber rope would be 1/2 inch squared or 1/4
lar type of rope. The difference is caused by    ton. The rule of thumb allows a FS of
the application of a safety factor. To obtain    about 4.




                                                                                  Rope 1-3
FM 5-125




                                 CARE OF FIBER ROPE
The strength and useful life of fiber rope is   grit between the fibers cuts them and
shortened considerably by improper care.        reduces the rope's strength.
To prolong its life and strength, observe the
                                                Slacken taut lines before they are
following guidelines:                           exposed to rain or dampness because
    Ensure that it is dry and then stored in    a wet rope shrinks and may break.
    a cool, dry place. This reduces the pos-    Thaw a frozen rope completely before
     sibility of mildew and rotting.            using it; otherwise the frozen fibers
                                                will break as they resist bending.
     Coil it on a spool or hang it from pegs
     in a way that allows air circulation.      Avoid exposure to excessive heat and
                                                fumes of chemicals; heat or boiling
     Avoid dragging it through sand or dirt     water decreases rope strength about
     or pulling it over sharp edges. Sand or    20 percent.


1-4 Rope
                                                                                   FM 5-125



                              HANDLING OF FIBER ROPE
New rope is coiled, bound, and wrapped in       the end of the rope. This should be at the
burlap. The protective covering should not      bottom of the coil (see Figure 1-2). If it is
be removed until the rope is to be used. This   not, turn the coil over so the end is at the
protects it during storage and prevents tan-    bottom. Pull the end up through the center
gling. To open the new rope, strip off the      of the coil. As the rope comes up, it unwinds
burlap wrapping and look inside the coil for    in a counterclockwise direction.




                                                                                 Rope 1-5
FM 5-125


                             INSPECTION OF FIBER ROPE
The outside appearance of fiber rope is not or broken yarns ordinarily are easy to iden-
always a good indication of its internal con- tify. Dirt and sawdust-like material inside a
dition. Rope softens with use. Dampness, rope, caused by chafing, indicate damage.
heavy strain, fraying and breaking of In rope having a central core, the core
strands, and chafing on rough edges all should not break away in small pieces when
weaken it considerably. Overloading rope examined. If it does, this is an indication
may cause it to break, with possible heavy that a rope has been overstrained.
damage to material and serious injury to If a rope appears to be satisfactory in all
personnel. For this reason, inspect it care- other respects, pull out two fibers and try to
fully at regular intervals to determine its break them. Sound fibers should offer con-
condition. Untwist the strands slightly to siderable resistance to breakage. When you
open a rope so that you can examine the find unsatisfactory conditions, destroy a
inside. Mildewed rope has a musty odor rope or cut it up in short pieces to prevent
and the inner fibers of the strands have a its being used in hoisting. You can use the
dark, stained appearance. Broken strands      short pieces for other purposes.

                                  Section II. Wire Rope
The basic element of wire rope is the individ-      usually wound or laid together in the opposite
ual wire, which is made of steel or iron in vari-   direction of the lay of the strands. Strands
ous sizes. Wires are laid together to form          are then wound around a central core that
strands, and strands are laid together to form      supports
                                                       -       and maintains the position of
rope (see Figure 1-3). Individual wires are         strands during bending and load stresses.




1-6 Rope
                                                                                        FM 5-125



In some wire ropes, the wires and strands            completed rope. As a result, preformed wire
are preformed. Preforming is a method of             rope does not contain the internal stresses
presetting the wires in the strands (and the         found in the nonpreformed wire rope; there-
strands in the rope) into the permanent heli-        fore, it does not untwist as easily and is
cal or corkscrew form they will have in the          more flexible than nonpreformed wire rope.

                            TYPES OF WIRE ROPE CORES
The core of wire rope may be constructed of of the core and distortion of the rope strand.
fiber rope, independent wire rope, or a wire Furthermore, if the rope is subjected to
strand.                                      excessive heat, the vegetable or synthetic
                                             fibers may be damaged.
             FIBER-ROPE CORES
                                                         INDEPENDENT, WIRE-ROPE CORES
The fiber-rope core can be of vegetable or
synthetic fibers. It is treated with a special       Under severe conditions, an independent,
lubricant that helps keep wire rope lubri-           wire-rope core is normally used. This is
cated internally. Under tension, wire rope           actually a separate smaller wire rope that
contracts, forcing the lubricant from the core       acts as a core and adds strength to the rope.
into the rope. This type of core also acts as a
cushion for the strands when they are under                    WIRE-STRAND CORES
stress, preventing internal crushing of indi-
vidual wires. The limitations of fiber-rope          A wire-strand core consists of a single
cores are reached when pressure, such as             strand that is of the same or a more flexible
crushing on the drum, results in the collapse        construction than the main rope strands.


                              CLASSIFICATION OF WIRE ROPE
Wire rope is classified by the number of             rope because many inner strands are pro-
strands, the number of wires per strand, the         tected from abrasion by the outer strands.
strand construction, and the type of lay.            The stiffest and strongest type for general
                                                     use is the 6-by-19 rope. It may be used over
    WIRE AND STRAND COMBINATIONS                     sheaves of large diameter if the speed is
                                                     kept to moderate levels. It is not suitable
Wire and strand combinations vary accord-            for rapid operation or for use over small
ing to the purpose for which a rope is               sheaves because of its stiffness. The 6-by-7
intended (see Figure 1-4, page 1-8). Rope            wire rope is the least flexible of the stan-
with smaller and more numerous wires                 dard rope constructions. It can withstand
is more flexible; however, it is less resistant      abrasive wear because of the large outer
to external abrasion. Rope made up of a              wires.
smaller number of larger wires is more resis-
tant to external abrasion but is less flexible.
                                                                       LAY
The 6-by-37 wire rope (6 strands, each made
up of 37 wires) is the most flexible of the          Lay refers to the direction of winding of
standard six-strand ropes. This flexibility          wires in strands and strands in rope (see
allows it to be used with small drums and            Figure 1-5, page 1-8). Both may be wound in
sheaves, such as on cranes. It is a very efficient   the same direction, or they may be wound in


                                                                                      Rope 1-7
FM 5-125




                                               the supported load, such as in drill rods and
                                               tubes for deep-well drilling.

                                                                 Lang Lay
                                               In lang lay, strands and wires are wound in
                                               the same direction. Because of the greater
                                               length of exposed wires, lang lay assures
                                               longer abrasion resistance of wires, less
                                               radial pressure on small diameter sheaves
                                               or drums by rope, and less binding stresses
                                               in wire than in regular lay wire rope. Disad-
                                               vantages of lang lay are its tendencies to
                                               kink and unlay or open up the strands,
opposite directions. The three types of rope   which makes it undesirable for use where
lays are--                                     grit, dust, and moisture are present. The
                                               standard direction of lang lay is right
    Regular.                                   (strands and wires wound right), although it
    Lang.                                      also comes in left lay (strands and wires
                                               wound left).
    Reverse.
                                                               Reverse Lay
                 Regular Lay                   In reverse lay, the wires of any strand are
In regular lay, strands and wires are wound    wound in the opposite direction of the wires
in opposite directions. The most common lay    in the adjacent strands. Reverse lay applies
in wire rope is right regular lay (strands     to ropes in which the strands are alternately
                                               regular lay and lang lay. The use of reverse
wound right, wires wound left). Left regular   lay rope is usually limited to certain types of
lay (strands wound left, wires wound right)    conveyors. The standard direction of lay is
is used where the untwisting rotation of the   right (strands wound right), as it is for both
rope counteracts the unscrewing forces in      regular-lay and lang-lay ropes.


1-8 Rope
                                                                                FM 5-125


                          CHARACTERISTICS OF WIRE ROPE
Wire rope is characterized by its size, of safety must be provided when applying a
weight, and strength.                         load to a wire rope, the BS is divided by an
                                              appropriate FS to obtain the SWC for that
                     SIZE                     particular  type of service (see Table 1-3,
                                              page 1-11).
The size of wire rope is designated by its
diameter in inches. To determine the size of You should use the FS given in Table 1-3 in
a wire rope, measure its greatest diameter all cases where rope will be in service for a
(see Figure 1-6).                             considerable time. As a rule of thumb, you
                                              can square the diameter of wire rope in,
                   WEIGHT                     inches, and multiply by 8 to obtain the SWC
                                              in tons:
The weight of wire rope varies with the size                2
and the type of construction. No rule of         SWC = 8D
thumb can be given for determining the A value obtained in this manner will not
weight. Approximate weights for certain always agree with the FS given in Table 1-3.
sizes are given in Table 1-2, page 1-10.      The table is more accurate. The proper FS
                                              depends not only on loads applied but also
                  STRENGTH                    on the--
The strength of wire rope is determined by         Speed of the operation.
its size and grade and the method of fabrica-      Type of fittings used for securing the
tion. The individual wires may be made of          rope ends.
various materials, including traction steel,
mild plow steel (MPS), improved plow steel         Acceleration and deceleration.
(IPS), and extra IPS. Since a suitable margin      Length of the rope.




                                                                              Rope 1-9
FM 5-125




    Number, size, and location of sheaves           Possible loss of life and property if the
    and drums.                                      rope fails.
    Factors causing abrasion and corrosion.     Table 1-2 shows comparative BS of typical
    Facilities for inspection.                  wire ropes.


                                 CARE OF WIRE ROPE
Caring for wire rope properly includes          and storing it. When working with wire
reversing the ends and cleaning, lubricating,   rope, you should wear work gloves.



1-10 Rope
                                                                                     FM 5-125



                                                 on a used wire rope. Remove rust at regu-
                                                 lar intervals by using a wire brush. Always
                                                 clean the rope carefully just before lubricat-
                                                 ing it. The object of cleaning at that time is
                                                 to remove all foreign material and old
                                                 lubricant from the valleys between the
                                                 strands and from the spaces between the
                                                 outer wires to permit the newly applied
                                                 lubricant free entrance into the rope.

                                                                LUBRICATING
                                                 At the time of fabrication, a lubricant is
                                                 applied to wire rope. However, this lubri-
                                                 cant generally does not last throughout the
                                                 life of the rope, which makes relubrication
                                                 necessary. To lubricate, use a good grade of
                                                 oil or grease. It should be free of acids and
  REVERSING OR CUTTING BACK ENDS                 alkalis and should be light enough to pene-
                                                 trate between the wires and strands. Brush
To obtain increased service from wire rope,      the lubricant on, or apply it by passing the
it is sometimes advisable to either reverse or   rope through a trough or box containing the
cut back the ends. Reversing the ends is         lubricant. Apply it as uniformly as possible
more satisfactory because frequently the         throughout the length of the rope.
wear and fatigue on rope are more severe at
certain points than at others. To reverse the
ends, detach the drum end of the rope from                         STORING
the drum, remove the rope from the end
attachment, and place the drum end of the        If wire rope is to be stored for any length of
rope in the end attachment. Then fasten the      time, you should always clean and lubri-
end that you removed from the end attach-        cate it first. If you apply the lubricant prop-
ment to the drum. Cutting back the end has       erly and store the wire in a place that is
a similar effect, but there is not as much       protected from the weather and from chem-
change involved. Cut a short length off the      icals and fumes, corrosion will be virtually
end of the rope and place the new end in the     eliminated. Although the effects of rusting
fitting, thus removing the section that has      and corrosion of the wires and deterioration
sustained the greatest local fatigue.
                                                 of the fiber core are difficult to estimate, it
                                                 is certain that they will sharply decrease
                 CLEANING                        the strength of the rope. Before storing,
Scraping or steaming will remove most of         coil the rope on a spool and tag it properly
the dirt or grit that may have accumulated       as to size and length.

                             HANDLING OF WIRE ROPE
Handling wire rope may involve kinking, coil- handling wire rope, you should wear
ing, unreeling, seizing, welding, cutting,    work gloves.
or the use of drums and sheaves. When



                                                                                   Rope 1-11
FM 5-125



                  KINKING                                         UNREELING
When handling loose wire rope, small loops        When removing wire rope from a reel or
frequently form in the slack portion (see Fig-    coil, it is imperative that the reel or coil
ure 1-7). If you apply tension while these        rotate as the rope unwinds. Mount the reel
loops are in position, they will not              as shown in Figure 1-8. Then pull the rope
straighten out but will form sharp kinks,         from the reel by holding the end of the rope
resulting in unlaying of the rope. You
should straighten out all of these loops          and walking away from the reel, which
before applying a load. After a kink has          rotates as the rope unwinds. If wire rope is
formed in wire rope, it is impossible to          in a small coil, stand the coil on end and roll
remove it. Since the strength of the rope is      it along the ground (see Figure 1-9). If loops
seriously damaged at the point where a kink       form in the wire rope, carefully remove
occurs, cut out that portion before using the     them before they form kinks.
rope again.
                                                                   SEIZING
                   COILING
                                                  Seizing is the most satisfactory method of
Small loops or twists will form if rope is        binding the end of a wire rope, although
being wound into the coil in a direction that     welding will also hold the ends together sat-
is opposite to the lay. Coil left-lay wire rope   isfactorily. The seizing will last as long as
in a counterclockwise direction and right-
lay wire rope in a clockwise direction.           desired, and there is no danger of weaken-
                                                  ing the wire through the application of heat.
                                                  Wire rope is seized as shown in Figure 1-10,
                                                  page 1-14. There are three convenient rules
                                                  for determining the number of seizings,
                                                  lengths, and space between seizings. In
                                                  each case when the calculation results in a
                                                  fraction, use the next larger whole num-
                                                  ber. The following calculations are based on
                                                  a 4-inch diameter wire rope:
                                                       The number of seizings to be applied
                                                       equals approximately three times the
                                                       diameter of the rope (number of seiz-
                                                       ings = SD).
                                                       Example: 3 x 3/4 (D) = 2 1/4. Use 3
                                                       seizings.
                                                       Each seizing should be 1 to 1 1/2 times
                                                       as long as the diameter of the rope.
                                                       (length of seizing= 1 1/2D).
                                                       The seizings should be spaced a dis-
                                                       tance apart equal to twice the diameter
                                                       (spacing = 2D).
                                                  Example: 2 x 3/4 (D) = 1 1/2. Use 2-inch
                                                  spaces.


1-12 Rope
 FM 5-125




Rope 1-13
FM 5-125




   Note: Always change the fraction               apply more heat than is essential to fuse the
   to the next larger whole number.               metal.

                  WELDING                                            CUTTING
You can bind wire-rope ends together by fus-      You can cut wire rope with a wire-rope cut-
ing or welding the wires. This is a satisfac-     ter, a cold chisel, a hacksaw, bolt clippers, or
tory method if you do it carefully, as it does    an oxyacetylene cutting torch (see Figure
not increase the size of the rope and requires    1-11). Before cutting wire rope, tightly bind
little time to complete. Before welding rope,     the strands to prevent unlaying. Secure the
cut a short piece of the core out of the end so   ends that are to be cut by seizing or welding
that a clean weld will result and the core        them. To use the wire-rope cutter, insert
will not be burned deep into the rope. Keep       the wire rope in the bottom of the cutter
the area heated to a minimum and do not           with the blade of the cutter coming between


1-14 Rope
                                                                                  FM 5-125




the two central seizings. Push the blade       other in addition to bending. Keep this
down against the wire rope and strike the      bending and moving of wires to a minimum
top of the blade sharply with a sledge ham-    to reduce wear. If the sheave or drum
mer several times. Use the bolt clippers on    diameter is sufficiently large, the loss of
wire rope of fairly small diameter; however,   strength due to bending wire rope around
use an oxyacetylene torch on wire rope of      it will be about 5 or 6 percent. In all cases,
any diameter. The hacksaw and cold chisel      keep the speed of the rope over the sheaves
are slower methods of cutting.                 or drum as slow as is consistent with effi-
                                               cient work to decrease wear on the rope. It
           DRUMS AND SHEAVES                   is impossible to give an absolute minimum
                                               size for each sheave or drum, since a num-
The size and location of the sheaves and
drums about which wire rope operates and       ber of factors enter into this decision. How-
the speed with which the rope passes over      ever, Table 1-4, page 1-16, shows the
the sheaves have a definite effect on the      minimum recommended sheave and drum
rope's strength and service life.              diameters for several wire-rope sizes. The
                                               sheave diameter always should be as large
                                               as possible and, except for very flexible
                    Size                       rope, never less than 20 times the wire-
Each time wire rope is bent, the individual    rope diameter. This figure has been
strands must move with respect to each         adopted widely.



                                                                                Rope 1-15
FM 5-125




                  Location                    in smooth layers. Overlapping results in
You should reeve the drums, sheaves, and      binding, causing snatches on the line when
blocks used with wire rope and place them     the rope is unwound. To produce smooth lay-
in a manner to avoid reverse bends when-      ers, start the rope against one flange of the
ever possible (see Figure 1-12). A reverse    drum and keep tension on the line while
bend-occurs when rope bends in one direc-     winding. Start the rope against the right or
tion around one block, drum, or sheave and    left flange as necessary to match the direc-
bends in the opposite direction around the    tion of winding, so that when it is rewound
next. This causes the individual wires and    on the drum, the rope will curve in the
strands to do an unnecessary amount of        same manner as when it left the reel
shifting, which increases wear. Where you     (see Figure 1-13, page 1-18). A convenient
must use a reverse bend, the block, sheave,   method for determining the proper flange of
or drum causing the reversal should be of     the drum for starting the rope is known as
larger diameter than ordinarily used.         the hand rule (see Figure 1-14, page 1-19).
Space the bend as far apart as possible so
there will be more time allowed between       The extended index finger in this figure
the bending motions.                          points at the on-winding rope. The turns of
                                              the rope are wound on the drum close
                                              together to prevent the possibility of crush-
                  Winding                     ing and abrasion of the rope while it is wind-
Do not overlap wire-rope turns when wind-     ing and to prevent binding or snatching
ing them on the drum of a winch; wrap them    when it is unwound. If necessary, use a


1-16 Rope
                                                                                 FM 5-125




wood stick be to force the turns closer       wire in the grooves formed by the first
together. Striking the wire with a hammer     layer; however, cross each turn of the rope
or other metal object damages the individ-    in the second layer over two turns of the
ual wires in the rope. If possible, wind      first layer (see Figure 1-15, page 1-20).
only a single layer of wire rope on the       Wind the third layer in the grooves of the
drum. Where it is necessary to wind addi-     second layer; however, each turn of the
tional layers, wind them so as to elimi-      rope will cross over two turns of the second
nate the binding. Wind the second layer of    layer.
turns over the first layer by placing the

                             INSPECTION OF WIRE ROPE
Inspect wire rope frequently. Replace       the amount of use. A rope that is used 1 or
frayed, kinked, worn, or corroded rope. The 2 hours a week requires less frequent inspec-
frequency of inspection is determined by    tion than one that is used 24 hours a day.



                                                                               Rope 1-17
FM 5-125




              PROCEDURES                       another, causing unequal load distribu-
Carefully inspect the weak points in rope      tion at this point.
and the points where the greatest stress       Four percent of the total number of
occurs. Worn spots will show up as shiny       wires composing a type of wire rope are
flattened spots on the wires. If the outer     found to be broken in one strand (the
wires have been reduced in diameter by one-    distance in which one strand makes
fourth, the worn spot is unsafe.               one complete turn around the rope).
Inspect broken wires to determine whether      Three broken wires are found in one
it is a single broken wire or several wires.   strand of 6-by-7 rope; if six broken
Rope is unsafe if--                            wires are found in one strand of 6-by-
                                               19 rope; or if nine broken wires are
    Individual wires are broken next to one    found in one strand of 6-by-37 rope.



1-18 Rope
                                                                          FM 5-125




           CAUSES OF FAILURE                 Overwinding or crosswinding it on
Wire rope failure is commonly caused by--    drums.
     Sizing, constructing, or grading it     Operating it over drums and sheaves
     incorrectly.                            that are out of alignment.
     Allowing it to drag over obstacles.     Permitting it to jump sheaves.
     Lubricating it improperly.              Subjecting it to moisture or acid fumes.
    Operating it over drums and sheaves of   Permitting it to untwist.
    inadequate size.                         Kinking.




                                                                        Rope 1-19
FM 5-125




1-20 Rope
                                                                                     FM 5-125




                                      CHAPTER              2


        Knots,            Splices,                Attachments,                and
                                      Ladders

                     Section I. Knots, Hitches, and Lashings
A study of the terminology pictured in Figure        will aid in understanding the methods of
2-1 and the definitions in Table 2-1, page 2-2,      knotting presented in this section.




                                                  Knots, Splices, Attachments, and Ladders 2-1
FM 5-125




The raw, cut end of a rope has a tendency to       the size of the rope. The whipped end of a
untwist and should always be knotted or fas-       rope will still thread through blocks or
tened in some manner to prevent this               other openings. Before cutting a rope, place
untwisting. Whipping is one method of fas-         two whippings on the rope 1 or 2 inches
tening the end of the rope to prevent              apart and make the cut between the whip-
untwisting (see Figure 2-2). A rope is             pings (see Figure 2-2). This will prevent the
whipped by wrapping the end tightly with a         cut ends from untwisting immediately
small cord. This method is particularly satis-     after they are cut.
factory because there is very little increase in

                                           KNOTS
A knot is an interlacement of the parts         used as a stopper to prevent a rope from
of one or more flexible bodies, such as cord-   passing through an opening.
age rope, forming a lump. It is also any tie or A good knot must be easy to tie, must hold
fastening formed with a rope, including         without slipping, and must be easy to
bends, hitches, and splices. A knot is often    untie. The choice of the best knot, bend, or


2-2 Knots, Splices, Attachments, and Ladders
                                    FM 5-125




Knots, Splices, Attachments, and Ladders 2-3
FM 5-125



hitch to use depends largely on the job it      the end of a rope from untwisting, to form a
has to do. In general, knots can be classi-     knob at the end of a rope, or to serve as a
fied into three groups. They are--              part of another knot. When tied at the end
                                                or standing part of a rope, this knot prevents
     Knots at the end of a rope.                it from sliding through a block, hole, or
     Knots for joining two ropes.               another knot. Use it also to increase a per-
                                                son's grip on a rope. This knot reduces the
      Knots for making loops.                   strength of a straight rope by 55 percent.

     KNOTS AT THE END OF ROPE                                Figure-Eight Knot
Knots at the end of a rope fall into the fol-   Use the figure-eight knot to form a larger
lowing categories:                              knot at the end of a rope than would be
     Overhand knot.                             formed by an overhand knot (see Figure
                                                2-4). The knot prevents the end of the rope
     Figure-eight knot.                         from slipping through a fastening or loop in
     Wall knot.                                 another rope or from unreeving when reeved
                                                through blocks. It is easy to untie.
              Overhand Knot
                                                                 Wall Knot
The overhand knot is the most commonly
used and the simplest of all knots (see Fig-    Use the wall knot with crown to prevent
ure 2-3). Use an overhand knot to prevent       the end of a rope from untwisting when an




2-4 Knots, Splices, Attachments, and Ladders
                                                                                     FM 5-125



enlarged end is not objectionable (see Figure        KNOTS FOR JOINING TWO ROPES
2-5). The wall knot also makes a desirable
knot to prevent the end of the rope from slip-   Knots for joining two ropes fall into the fol-
ping through small openings, as when using       lowing categories:
rope handles on boxes. Use either the crown           Square knot.
or the wall knot separately to form semiper-
manent "stopper knots" tied with the end              Single sheet bend.
strands of a rope. The wall knot will prevent         Double sheet bend.
the rope from untwisting, but to make a
neat round knob, crown it (see Figure 2-6,            Carrick bend.
page 2-6). Notice that in the wall knot, the
ends come up through the bights, causing                         Square Knot
the strands to lead forward. In a crown
knot, the ends go down through the bights        Use the square knot to tie two ropes of
and point backward.                              equal size together so they will not slip (see




                                            Knots, Splices, Attachments, and Ladders 2-5
FM 5-125




Figure 2-7). Note that in the square knot,                       Double Sheet Bend
the end and standing part of one rope come         The double sheet bend has greater holding
out on the same side of the bight formed by        power than the single sheet bend for joining
the other rope. The square knot will not           ropes of equal or unequal diameter, joining
hold if the ropes are wet or if they are of dif-   wet ropes, or tying a rope to an eye (see Fig-
ferent sizes. It tightens under strain but         ure 2-9, page 2-8,). It will not slip or draw
can be untied by grasping the ends of the          tight under heavy loads. This knot is more
two bights and pulling the knot apart.             secure than the single sheet bend when used
   NOTE. It makes no difference                    in a spliced eye.
   whether the first crossing is tied
   left-over-right or right-over-left as                           Carrick Bend
   long as the second crossing is tied
   opposite to the first crossing.                 Use the carrick bend for heavy loads and for
                                                   joining large hawsers or heavy rope (see Fig-
                                                   ure 2-10, page 2-8). It will not draw tight
             Single Sheet Bend                     under a heavy load and can be untied easily
A single sheet bend, sometimes called a            if the ends are seized to their own standing
weaver's knot, has two major uses (see Fig-        part.
ure 2-8). They are--
     Tying together two ropes of unequal                  KNOTS FOR MAKING LOOPS
     size.                                         Knots for making loops fall into the follow-
     Tying a rope to an eye.                       ing categories:
This knot will draw tight but will loosen or            Bowline.
slip when the lines are slackened. The sin-             Double bowline.
gle sheet bend is stronger and unties easier
than the square knot.                                   Running bowline.



2-6 Knots, Splices, Attachments, and Ladders
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Knots, Splices, Attachments, and Ladders 2-7
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2-8 Knots, Splices, Attachments, and Ladders
                                                                                       FM 5-125



     Bowline on a bight.                          ing two loops support his legs. A notched
     Spanish bowline.                             board that passes through the two loops
                                                  makes a comfortable seat known as a boat-
     French bowline.                              swain's chair. This chair is discussed in the
                                                  scaffolding section of this manual (see Chap-
     Speir knot.                                  ter 6).
     Cat's-paw.
                                                                Running Bowline
     Figure eight with an extra turn.
                                                  The running bowline forms a strong running
                                                  loop (see Figure 2-13, page 2-10). It is a con-
                    Bowline                       venient form of running an eye. The run-
The bowline is one of the most common             ning bowline provides a sling of the choker
knots and has a variety of uses, one of which     type at the end of a single line. Use it when
is the lowering of men and material (see Fig-     tying a handline around an object at a point
ure 2-11). It is the best knot for forming a      that you cannot safely reach, such as the end
single loop that will not tighten or slip under   of a limb.
strain and can be untied easily if each run-
ning end is seized to its own standing part.                   Bowline on a Bight
The bowline forms a loop that may be of any
length.                                           This knot forms two nonslipping loops (see
                                                  Figure 2-14, page 2-11). You can use the
                                                  bowline on a bight for the same purpose as a
               Double Bowline                     boatswain's chair. It does not leave both
                                                  hands free, but its twin nonslipping loops
The double bowline forms three nonslipping        form a comfortable seat. Use it when--
loops (see Figure 2-12, page 2-10). Use this
knot to sling a man. As he sits in the slings,         You need more strength than a single
one loop supports his back and the remain-             bowline will give.




                                             Knots, Splices, Attachments, and Ladders 2-9
FM 5-125




2-10 Knots, Splices, Attachments, and Ladders
                                                                                     FM 5-125




     You need to form a loop at some point       Spanish bowline in rescue work or to give a
     in a rope other than at the end.            twofold grip for lifting a pipe or other round
                                                 objects in a sling.
     You do not have access to the end of a
     rope.
                                                                French Bowline
You can easily untie the bowline on a bight
and tie it at the end of a rope by doubling      You can use the French bowline as a sling to
the rope for a short section.                    lift injured men (see Figure 2-16, page 2-12).
                                                 When used for this purpose, one loop is a
                                                 seat and the other loop is put around the
              Spanish Bowline                    body under the arms. The injured man's
 You can tie a Spanish bowline at any point      weight keeps the two loops tight so that he
in a rope, either at a place where the line is   cannot fall out. It is particularly useful as a
double or at an end that has been doubled        sling for an unconscious man. Also, use the
back (see Figure 2-15, page 2-12). Use the       French bowline when working alone and you


                                            Knots, Splices, Attachments, and Ladders 2-11
FM 5-125




need your hands free. The two loops of this        a one-rope bridge across a small stream.
knot can be adjusted to the size required.         You can tie and untie it easily.

                   Speir Knot                            KNOTS FOR TIGHTENING A ROPE
Use a speir knot when you need a fixed loop,       The types of knots used for tightening a rope
a nonslip knot, and a quick release (see Fig-      are the butterfly knot and the baker bow-
ure 2-17). You can tie this knot quickly and       line.
release it by pulling on the running end.
                                                                   Butterfly Knot
                   Cat's-paw
                                                   Use the butterfly knot is to pull taut a high
Use a cat's-paw to fasten an endless sling to      line, handline, tread rope for foot bridges, or
a hook, or make it at the end of a rope to fas-    similar installations (see Figure 2-20, page
ten the rope to a hook (see Figure 2-18). You      2-14). Using this knot provides the capabil-
can tie or untie it easily. This knot, which is    ity to tighten a fixed rope when mechanical
really a form of a hitch, is a more satisfactory   means are not available. (You can also use
way of attaching a rope to a hook than the         the harness hitch for this purpose [see Fig-
blackwall hitch. It will not slip off and need     ure 2-32, page 2-22]). The butterfly knot will
not be kept taut to make it hold.                  not jam if a stick is placed between the two
                                                   upper loops.
      Figure Eight With an Extra Turn
Use a figure eight with an extra turn to                          Baker Bowline
tighten a rope (see Figure 2-19, page 2-14).       You can use the baker bowline for the same
This knot is especially suitable for tightening    purpose as the butterfly knot and for lashing
                                                   cargo (see Figure 2-21, pages 2-15 and 2-16).


2-12 Knots, Splices, Attachments, and Ladders
                                        FM 5-125



     When used to lash cargo, secure one end
     with two half hitches, pass the rope over the
     cargo and tie a baker bowline, then secure
     the lashing with a slippery half hitch. To
     release the rope, simply pull on the running
     end. Advantages of the baker bowline are
     that it can be--
          Tied easily.
          Adjusted without losing control.
          Released quickly.

               KNOTS FOR WIRE ROPE
     Under special circumstances, when wire-
     rope fittings are not available and it is nec-
     essary to fasten wire rope by some other
     manner, you can use certain knots. In all
     knots made with wire rope, fasten the
     running end of the rope to the standing
     part after tying the knot. When wire-rope
     clips are available, use them to fasten the
     running end. If clips are not available, use




Knots, Splices, Attachments, and Ladders 2-13
FM 5-125




2-14 Knots, Splices, Attachments, and Ladders
                                    FM 5-125




Knots, Splices, Attachments, and Ladders 2-15
FM 5-125




 2-16 Knots, Splices, Attachments, and Ladders
                                                                                    FM 5-125



wire or strands of cordage. Check all knots      sive wear, cut off a short length of the end
in wire rope periodically for wear or signs of   of the rope, including the knot, and tie a
breakage. If there is any reason to believe      new knot. Use the fisherman's bend, clove
that the knot has been subjected to exces-       hitch, and carrick bend to fasten wire rope.

                                         HITCHES
A hitch is any of various knots used to form         Sheepshank.
a temporary noose in a rope or to secure a           Fisherman's bend.
rope around a timber, pipe, or post so that
it will hold temporarily but can be readily
undone. The types of hitches are as follows:                     HALF HITCH
      Half hitch.                                Use the half hitch to tie a rope to a timber
                                                 or to a larger rope (see Figure 2-22, A). It
      Two half hitches.                          will hold against a steady pull on the
      Round turn and two half hitches.           standing part of the rope; however, it is not
                                                 a secure hitch. You can use the half hitch
     Timber hitch.                               to secure the free end of a rope and as an
     Timber hitch and half hitch.                aid to and the foundation of many knots.
                                                 For example, it is the start of a timber
     Clove hitch.                                hitch and a part of the fisherman's knot. It
     Rolling hitch.                              also makes the rolling hitch more secure.
     Telegraph hitch.
                                                           TWO HALF HITCHES
     Mooring hitch.
                                                 Two half hitches are especially useful for
      Scaffold hitch.                            securing the running end of a rope to the
      Blackwall hitch.                           standing part (see Figure 2-22, B). If the
                                                 two hitches are slid together along the
      Harness hitch.                             standing part to form a single knot, the
      Girth hitch.                               knot becomes a clove hitch.




                                           Knots, Splices, Attachments, and Ladders 2-17
FM 5-125



 ROUND TURN AND TWO HALF HITCHES
Another hitch used to fasten a rope to a
pole, timber, or spar is the round turn and
two half hitches (see Figure 2-23). For
greater security, seize the running end of
the rope to the standing part. This hitch
does not jam.

               TIMBER HITCH
Use the timber hitch to move heavy timber
or poles (see Figure 2-24). It is excellent for
securing a piece of lumber or similar
objects. The pressure of the coils, one over
the other, holds the timber securely; the
more tension applied, the tighter the hitch
becomes about the timber. It will not slip                        CLOVE HITCH
but will readily loosen when the strain is        The clove hitch is one of the most widely
relieved.                                         used knots (see Figure 2-26, page 2-19). You
                                                  can use it to fasten a rope to a timber, pipe,
     TIMBER HITCH AND HALF HITCH                  or post. You can also use it to make other
                                                  knots. This knot puts very little strain on
A timber hitch and half hitch are combined        the fibers when the rope is put around an
to hold heavy timber or poles when they are       object in one continuous direction. You can
being lifted or dragged (see Figure 2-25). A      tie a clove hitch at any point in a rope. If
timber hitch used alone may become untied         there is not constant tension on the rope,
when the rope is slack or when a sudden           another loop (round of the rope around the
strain is put on it.                              object and under the center of the clove
                                                  hitch) will permit a tightening and slacken-
                                                  ing motion of the rope.

                                                               ROLLING HITCH
                                                  Use the rolling hitch to secure a rope to
                                                  another rope or to fasten it to a pole or pipe




2-18 Knots, Splices, Attachments, and Ladders
                                                                                      FM 5-125




so that the rope will not slip (see Figure       This hitch grips tightly and is easily
2-27, page 2-20). This knot grips tightly but    removed.
is easily moved along a rope or pole when
the strain is relieved.                                       SCAFFOLD HITCH
                                                 Use the scaffold hitch to support the end of a
              TELEGRAPH HITCH                    scaffold plank with a single rope (see Figure
The telegraph hitch is a very useful and         2-30, page 2-21). It prevents the plank from
secure hitch that you can use to hoist or haul   tilting.
posts and poles (see Figure 2-28, page 2-20).
It is easy to tie and untie and will not slip.                 BLACKWALL HITCH
             MOORING HITCH                       Use the blackwall hitch to fasten a rope to a
                                                 hook (see Figure 2-31, page 2-22). Gener-
Use the mooring hitch, also called rolling or    ally, use it to attach a rope, temporarily, to a
magnus hitch, to fasten a rope around a          hook or similar object in derrick work. The
mooring post or to attach a rope at a right      hitch holds only when subjected to a con-
angle to a post (see Figure 2-29, page 2-21).    stant strain or when used in the middle of a



                                           Knots, Splices, Attachments, and Ladders 2-19
FM 5-125




2-20 Knots, Splices, Attachments, and Ladders
                                    FM 5-125




Knots, Splices, Attachments, and Ladders 2-21
FM 5-125




rope with both ends secured. Human life        The hitch is tied only in the middle of a rope.
and breakable equipment should never be        It will slip if only one end of the rope is
entrusted to the blackwall hitch.              pulled.

             HARNESS HITCH                                    GIRTH HITCH
The harness hitch forms a nonslipping loop     Use the girth hitch to tie suspender ropes to
in a rope (see Figure 2-32). It is often       hand ropes when constructing expedient foot
employed by putting an arm through the         bridges (see Figure 2-33). It is a simple and
loop, then placing the loop on the shoulder    convenient hitch for many other uses of
and pulling the object attached to the rope.   ropes and cords.




2-22 Knots, Splices, Attachments, and Ladders
                                          FM 5-125



                      SHEEPSHANK
      A sheepshank is a method of shortening a
      rope, but you can use it to take the load off a
      weak spot in the rope (see Figure 2-34). It is
      only a temporary knot unless the eyes are
      fastened to the standing part on each end.

                 FISHERMAN'S BEND
     The fisherman's bend is an excellent knot for
     attaching a rope to a light anchor, a ring,
     or a rectangular piece of stone (see Figure 2-
     35, page 2-24). You can use it to fasten a
     rope or cable to a ring or post. Also use it
     where there will be a slackening and tight-
     ening motion in the rope.




Knots, Splices, Attachments, and Ladders 2-23
FM 5-125




                                        LASHINGS
A lashing is as rope, wire, or chain used for               SHEARS LASHING
binding, wrapping, or fastening. The types      Use the shears lashing to lash two spars
of lashings include square, shears, and         together at one end to form an expedient
block.                                          device called a shears (see Figure 2-37). Do
                                                this by laying two spars side by side,
             SQUARE LASHING                     spaced about one-third of the diameter of a
Use the square lashing to lash two spars        spar apart, with the butt ends together.
together at right angles to each other (see     Start the shears lashing a short distance in
Figure 2-36). To tie a square lashing, begin    from the top of one of the spars by tying the
with a clove hitch on one spar and make a       end of the rope to it with a clove hitch.
minimum of four complete turns around           Then make eight tight turns around both
both members. Continue with two frapping        spars above the clove hitch. Tighten the
turns between the vertical and the horizon-     lashing with a minimum of two frapping
tal spar to tighten the lashing. Tie off the    turns around the eight turns. Finish the
running end to the opposite spar from           shears lashing by tying the end of the rope
which you started with another clove hitch      to the opposite spar from which you started
to finish the square lashing.                   with another clove hitch.


2-24 Knots, Splices, Attachments, and Ladders
                                   FM 5-125




Knots, Splices, Attachments, and Ladders 2-25
FM 5-125



             BLOCK LASHING
Use the block lashing to tie a tackle block to
a spar (see Figure 2-38). First, make three
right turns of the rope around the spar
where the tackle block is to be attached.
Pass the next two turns of the rope through
the mouth of the hook or shackle of the
tackle block and drawn tightly. Then put
three additional taut turns of the rope
around the spar above the hook or shackle.
Complete the block lashing by tying the two
ends of the rope together with a square
knot. When a sling is supported by a block
lashing, pass the sling through the center
four turns.

                                  Section II. Splices
Splicing is a method of joining fiber or wire    The methods of making all four types of
rope by unlaying strands of both ends and        splices are similar. They generally consist
interweaving these strands together. The         of the following basic steps--
general types of splices are--
                                                      Unlaying the strands of the rope.
     A short splice.
                                                      Placing the rope ends together.
    An eye or side splice.
    A long splice.                                    Interweaving the strands and tucking
                                                      them into the rope.
    A crown or back splice.

                                 FIBER-ROPE SPLICES
When one strand of a rope is broken, you         short splice because a minimum reduction
cannot repair it by tying the ends together      in rope length takes place in making the
because this would shorten the strand.           splice. This splice is frequently used to
Repair it by inserting a strand longer than      repair damaged ropes when two ropes of the
the break and tying the ends together (see       same size are to be joined together perma-
Figure 2-39).                                    nently. Cut out the damaged parts of the
                                                 rope and splice the sound sections.
               SHORT SPLICE
The short splice is as strong as the rope in                EYE OR SIDE SPLICE
which it is made and will hold as much as a      Use the eye or side splice to make a perma-
long splice (see Figure 2-40). However, the      nent loop in the end of a rope (see Figure
short splice causes an increase in the diame-    2-41, page 2-28). You can use the loops,
ter of the rope for a short distance and can     made with or without a thimble, to fasten
be used only where this increase in diameter     the rope to a ring or hook. Use a thimble
will not affect operations. It is called the     to reduce wear. Use this splice also to splice



2-26 Knots, Splices, Attachments, and Ladders
                                    FM 5-125




Knots, Splices, Attachments, and Ladders 2-27
FM 5-125




one rope into the side of another. As a per-      The ropes to be joined should be the same
manent loop or eye, no knot can compare           lay and as nearly the same diameter as
with this splice for neatness and efficiency.     possible.

                LONG SPLICE                               CROWN OR BACK SPLICE
Use the long splice when the larger diameter      When you are splicing the end of a rope to
of the short splice has an adverse effect on      prevent unlaying, and a slight enlarge-
the use of the rope; use it also to splice long   ment of the end is not objectionable, use a
ropes that operate under heavy stress (see        crown splice to do this (see Figure 2-43,
Figure 2-42). This splice is as strong as the     page 2-30). Do not put any length of rope
rope itself. A skillfully made long splice will   into service without properly preparing the
run through sheaves without any difficulty.       ends.




2-28 Knots, Splices, Attachments, and Ladders
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Knots, Splices, Attachments, and Ladders 2-29
FM 5-125




2-30 Knots, Splices, Attachments, and Ladders
                                                                                        FM 5-125



                                    WIRE-ROPE      SPLICES
In splicing wire rope, it is extremely impor-      untwist the wire. A pocket knife may be
tant to use great care in laying the various       needed to cut the hemp core.
rope strands firmly into position. Slack
strands will not receive their full share of the                   SHORT SPLICE
load, which causes excessive stress to be put
on the other strands. The unequal stress           A short splice develops only from 70 to 90
distribution will decrease the possible ulti-      percent of the strength of the rope. Since a
mate strength of the splice. When using            short splice is bulky, it is used only for block
splices in places where their failure may          straps, slings, or where an enlargement of
result in material damage or may endanger          the diameter is of no importance. It is not
human lives, test the splices under stresses       suitable for splicing driving ropes or ropes
equal to at least twice their maximum work-        used in running tackles and should never
ing load before placing the ropes into service.    be put into a crane or hoist rope. The wire
Table 2-2 shows the amount or length of rope       rope splice differs from the fiber rope
to be unlaid on each of the two ends of the        short splice only in the method by which the
ropes and the amount of tuck for ropes of dif-     end strands are tucked (see Figure 2-45,
ferent diameters. As a rule of thumb, use          page 2-32).
the following:
     Long splice, 40 times the diameter.                       EYE OR SIDE SPLICE
     Short splice, 20 times the diameter.          An eye splice can be made with or without a
                                                   thimble. Use a thimble for every rope eye
You need only a few tools to splice wire rope.     unless special circumstances prohibit it (see
In addition to the tools shown in Figure 2-44,     Figure 2-46, page 2-33). The thimble pro-
page 2-32, a hammer and cold chisel are            tects the rope from sharp bends and abra-
often used to cut the ends of strands. Use         sive action. The efficiency of a well-made
two slings of marline and two sticks to            eye splice with a heavy-duty thimble varies




                                           Knots, Splices, Attachments, and Ladders 2-31
FM 5-125



                                           from 70 to 90 percent. Occasionally, it be-
                                           comes necessary to construct a field expedi-
                                           ent, called a hasty eye (see Figure 2-47).
                                           The hasty eye can be easily and quickly
                                           made but is limited to about 70 percent of
                                           the strength of the rope; consequently, it
                                           should not be used to hoist loads.

                                                         LONG SPLICE
                                           Use the long splice to join two ropes or to
                                           make an endless sling without increasing
                                           the thickness of the wire rope at the splice
                                           (see Figure 2-48, page 2-34). It is the best
                                           and most important kind of splice because it
                                           is strong and trim.

                                               Round-Strand, Regular-Lay Rope
                                           The directions given in Figure 2-48 are for
                                           making a 30-foot splice in a three-fourths




2-32 Knots, Splices, Attachments, and Ladders
                                   FM 5-125




Knots, Splices, Attachments, and Ladders 2-33
FM 5-125




inch regular-lay, round-strand, hemp-center      because of the tendency of the rope to
wire rope. Other strand combinations differ      untwist. Up to the point of tucking the
only when there is an uneven number of           ends, follow the procedure for regular lay.
strands. In splicing ropes having an odd         Then, instead of laying the strands side by
number of strands, make the odd tuck at the      side where they pass each other, cross
center of the splice.                            them over to increase the holding power of
                                                 the splice. At the point where they cross,
       Round-Strand, Lang-Lay Rope               untwist the strands for a length of about 3
                                                 inches so they cross over each other with-
In splicing a round-strand, Lang-lay rope, it    out materially increasing the diameter of
is advisable to make a slightly longer splice    the rope. Then finish the tucks in the
than for the same size rope of regular lay       usual manner.

                              Section III. Attachments
Most of the attachments used with wire rope      a number of attachments used with the eye
are designed to provide an eye on the end of     splice. Any two of the ends can be joined
the rope by which maximum strength can be        together, either directly or with the aid of a
obtained when the rope is connected with         shackle or end fitting. These attachments
another rope, hook, or ring. Figure 2-49 shows   for wire rope take the place of knots.


2-34 Knots, Splices, Attachments, and Ladders
                                                                                   FM 5-125




                                      END FITTINGS
An end fitting may be placed directly on wire   age to another wire rope. Table 2-3, page 2-
rope. Fittings that are easily and quickly      36 shows the number-and spacing of clips
changed are clips, clamps, and wedge sockets.   and the proper torque to apply to the nuts of
                                                the clips. After installing all the clips,
                                                tighten the clip farthest from the eye (thim-
                    CLIPS
                                                ble) with a torque wrench. Next, place the
Wire-rope clips are reliable and durable (see   rope under tension and tighten the clip next
Figure 2-50, page 2-36). Use them, repeat-      to the clip you tightened first. Tighten the
edly, to make eyes in wire rope, either for a   remaining clips in order, moving toward the
simple eye or an eye reinforced with a thim-    loop (thimble). After placing the rope in
ble, or to secure a wire-rope line or anchor-   service, tighten the clips again immediately



                                          Knots, Splices, Attachments, and Ladders 2-35
FM 5-125




2-36 Knots, Splices, Attachments, and Ladders
                                                                                     FM 5-125



after applying the working load and at fre-
quent intervals thereafter. Retightening is
necessary to compensate for the decrease in
rope diameter that occurs when the strands
adjust to the lengthwise strain caused by the
load. Position the clips so that they are
immediately accessible for inspection and
maintenance.

                  CLAMPS
A wire clamp can be used with or without a
thimble to make an eye in wire rope (see Fig-
ure 2-51). Ordinarily, use a clamp to make
an eye without a thimble. It has about 90
percent of the strength of the rope. Tighten
the two end collars with wrenches to force
the clamp to a good snug fit. This crushes
the pieces of rope firmly against each other.


                                      WEDGE SOCKET
Use a wedge-socket end fitting when it is tapered socket. The loop of wire rope must
necessary to change the fitting at frequent be inserted in the wedge socket so that the
intervals (see Figure 2-52, page 2-38). The standing part of the wire rope will form a
efficiency is about two-thirds of the strength nearly direct line to the clevis pin of the fit-
of the rope. It is made in two parts. The ting. A properly installed wedge-socket
socket itself has a tapered opening for the connection will tighten when a strain is
wire rope and a small wedge to go into this placed on the wire rope.

                               BASKET-SOCKET END FITTING
The basket-socket end fittings include closed its strength is sharply reduced and must be
sockets, open sockets, and bridge sockets considered to be about one-sixth the
(see Figure 2-53, page 2-38). This socket is strength of a zinc connection. In all cases,
ordinarily attached to the end of the rope the wire rope should lead from the socket in
with molten zinc or babbitt metal and is a line with the axis of the socket.
permanent end rifting. If this fitting is prop-
erly made up, it is as strong as the rope                   POURED METHOD
itself. If molten lead is used instead of zinc,
the strength of the connection must be The poured basket socket is the most satis-
assumed to be reduced to one-fourth the factory method in use (see Figure 2-54, page
strength of a zinc connection. The socket can 2-39). If the socketing is properly done, a
be made up by the dry method if facilities are wire rope, when tested to destruction, will
not available to make a poured fitting, but break before it will pull out from the socket.



                                           Knots, Splices, Attachments, and Ladders 2-37
FM 5-125




2-38 Knots, Splices, Attachments, and Ladders
                                    FM 5-125




Knots, Splices, Attachments, and Ladders 2-39
FM 5-125



               DRY METHOD                       method (see Figure 2-55). The strength of
                                                the connection must be assumed to be
The dry method should be used only when         reduced to about one-sixth of the strength
facilities are not available for the poured     of a poured zinc connection.

                                      STANCHIONS
The standard pipe stanchion is made up of a     modifying it, for a suspended walkway
l-inch diameter pipe (see Figure 2-56). Each    that uses two wire ropes on each side.
stanchion is 40 inches long. Two 3/4-inch       However, for handlines, remove or leave
wire-rope clips are fastened through holes in   off the lower wire-rope clip. For more infor-
the pipe with the centers of the clips 36       mation on types and uses of stanchions,
inches apart. Use this stanchion, without       see TM 5-270.




2-40 Knots, Splices, Attachments, and Ladders
                                                                               FM 5-125




                             Section IV. Rope Ladders
Ropes may be used in the construction of      hanging ladders and standoff ladders.

                                 HANGING LADDERS
Hanging ladders are made of wire or fiber               WIRE-ROPE LADDERS
rope anchored at the top and suspended ver-
tically. They are difficult to ascend and     Wire-rope uprights with pipe rungs make
descend, particularly for a man carrying a    the most satisfactory hanging ladders be-
pack or load and should be used only when     cause they are more rigid and do not sag as
necessary. The uprights of hanging ladders    much as hanging ladders made of other
may be made of wire or fiber rope and         material. Wire-rope uprights with wire-rope
anchored at the top and bottom.               rungs are usable.



                                        Knots, Splices, Attachments, and Ladders 2-41
FM 5-125



     Wire-Rope Ladder With Pipe Rungs          clips in the stanchion over 3/4-inch wire-rope
Make a wire-rope ladder using either l-inch    uprights (see Figure 2-57). If you use 3/8-inch
or 3/4-inch pipe rungs. The l-inch pipe        wire-rope uprights, insert 3/8-inch wire-rope
rungs are more satisfactory. For such lad-     clips in the pipe over the wire-rope uprights.
ders, use the standard pipe stanchion.         When you use 3/4-inch pipe rungs, space the
Space the pipe stanchions 12 inches apart in   rungs 12 inches apart in the ladder, but do
the ladder and insert the 3/4-inch wire-rope   not space the uprights more than 12 inches




2-42 Knots, Splices, Attachments, and Ladders
                                                                                      FM 5-125



apart because of using weaker pipe. The            first length in a series of U-shaped bends.
rungs may be fastened in place by two differ-      Lay out the second length in a similar man-
ent methods. In one method, drill a 7/16-          ner with the U-shaped bends in the opposite
inch diameter hole at each end of each pipe        direction from those in the first series and
rung and thread 3/8-inch wire-rope uprights        the horizontal rung portions overlapping
through the holes. To hold each rung in            (see Figure 2-58). Fasten a 3/8-inch wire-
place, fasten a 3/8-inch wire-rope clip about      rope clip on the overlapping rung portions at
the wire-rope upright at each end of each          each end of each rung to hold them firm.
rung after the rung is in its final position. In
the other method, cut the pipe rungs 12                      FIBER-ROPE LADDERS
inches long and weld the U-bolt of a 3/8-inch
rope clip to each end. Space the rungs 12          Fiber-rope uprights with wood or fiber-rope
inches apart on the 3/8-inch wire-rope             rungs are difficult to use because their
uprights. Place the saddle of the wire-rope        greater flexibility causes them to twist when
clips and the nuts on the U-bolts; tighten the     they are being used. Place a log at the break
                                                   of the ladder at the top to hold the uprights
nuts to hold the rungs in place.
                                                   and rungs away from a rock face to provide
                                                   better handholds and footholds. A single
 Wire-Rope Ladder With Wire-Rope Rungs             rock anchor at the bottom of the ladder is
Make a wire-rope ladder with wire-rope             usually sufficient. You can also use a pile of
rungs by laying the 3/8-inch diameter wire-        rocks as the bottom anchor for fiber-rope
rope uprights on the ground. Lay out the           hanging ladders.




                                             Knots, Splices, Attachments, and Ladders 2-43
FM 5-125



 Fiber-Rope Ladder With Fiber-Rope Rungs         rungs (see Figure 2-60). When you use
Make fiber-rope ladders with fiber-rope          native material, cut the rungs from 2-inch-
rungs by using two or three uprights. When       diameter material about 15 inches long.
you use three uprights, make a loop in the       Notch the ends of each rung and fasten the
center upright at the position of each rung      rung to the fiber-rope upright with a clove
(see Figure 2-59). Space the two outside         hitch. Space the rungs 12 inches apart.
uprights 20 inches apart. A loop and a single    Twist a piece of seizing wire about the back
splice hold each end of each rung to the out-    of the clove hitch to make it more secure and
side upright. A loop in the center of the rung   in a manner that will not snag the clothing
passes through the loop in the center            of persons climbing the ladder. If you make
upright. If you use only two uprights, hold      the rungs of finished lumber, cut them to
the rungs in place by a loop and a rolling       size and drill a 3/4-inch hole at each end.
hitch or a single splice at each upright. The    Oak lumber is best for this purpose. Put a
two uprights must be closer together, with       l/4-inch by 2-inch carriage bolt horizontally
shorter rungs, to stiffen the ladder. Ladders    through each end near the vertical hole to
of either type are very flexible and difficult   prevent splitting. Tie an overhand knot in
to climb.                                        the upright to support the rung. Then
                                                 thread the upright through the 3/4-inch hole
                                                 in the rung. Tie a second overhand knot in
   Fiber-Rope Ladder With Wood Rungs             the upright before you thread it through the
Make fiber-rope ladders with wood rungs by       next rung. Continue this Procedure until
using finished lumber or native material for     you reach-the desired length of the ladder.




2-44 Knots, Splices, Attachments, and Ladders
                                                                                FM 5-125


                                  STANDOFF LADDERS
Standoff ladders are easier to climb than transported easily. One or two standoff lad-
hanging ladders because they have two ders are adequate for most purposes, but
wood or metal uprights that hold them three or four hanging ladders must be pro-
rigid, and they are placed at an angle. Both vialed for the same purpose because they are
types of ladders can be prefabricated and more difficult to use.




                                        Knots, Splices, Attachments, and Ladders 2-45
                                                                                    FM 5-125




                                      CHAPTER 3


                                        Hoists


                            Section I. Chains and Hooks
Chains are much more resistant to abrasion        In lifting, chains, as well as fiber ropes
and corrosion than wire rope; use them            or wire ropes, can be tied to the load. But
where this type of deterioration is a problem,    for speed and convenience, it is much
as in marine work where anchor gear must          better to fasten a hook to the end of the
withstand the corrosive effects of seawater.      lifting line. Also, you can use hooks are
You can also use chains to lift heavy objects     in constructing blocks.
with sharp edges that would cut wire.


                                           CHAINS
Chains are made up of a series of links fas-
tened through each other. Each link is
made of a rod of wire bent into an oval
shape and welded at one or two points. The
weld ordinarily causes a slight bulge on the
side or end of the link (see Figure 3-1). The
chain size refers to the diameter, in inches,
of the rod used to make the link. Chains
usually stretch under excessive loading so
that the individual links bend slightly.
Bent links are a warning that the chain has
been overloaded and might fail suddenly
under a load. Wire rope, on the other hand,
fails a strand at a time, giving warning
before complete failure occurs. If a chain is
equipped with the proper hook, the hook
should start to fail first, indicating that the
chain is overloaded.
Several grades and types of chains are
available.




                                                                                 Hoists 3-1
FM 5-125



           STRENGTH OF CHAINS                   of a chain with a link thickness of 3/4 inch
To determine the SWC on a chain, apply a        is--
                                                                  2          2
FS to the breaking strength. The SWC ordi-          SWC = 8D = 8 (3/4) = 4.5 tons or
narily is assumed to be about one-sixth of          9,000 pounds
the BS, giving a FS of 6. Table 3-1 lists SWC   The figures given assume that the load is
for various chains. You can approximate the     applied in a straight pull rather than by an
SWC of an open-link chain by using the fol-     impact. An impact load occurs when an
lowing rule of thumb:                           object is dropped suddenly for a distance
  SWC = 8D
             2                                  and stopped. The impact load in such a
                                                case is several times the weight of the load.
  SWC = Safe working capacity, in tons
  D = Smallest link thickness or least diam-                CARE OF CHAINS
  eter measured in inches (see Figure 3-1,      When hoisting heavy metal objects using
  page 3-1)                                     chains for slings, insert padding around
Example: Using the rule of thumb, the SWC       the sharp corners of the load to protect the




3-2 Hoists
                                                                                   FM 5-125



chain links from being cut. The padding        Cut the smaller chain links with a bolt
may be either planks or heavy fabric. Do       cutter; cut large chain links with a hack-
not permit chains to twist or kink when        saw or an oxyacetylene torch. Inspect the
under strain. Never fasten chain links chain   chains frequently, depending on the
together with bolts or wire because such       amount of use. Do not paint chains to
connections weaken the chain and limit         prevent rusting because the paint will
its SWC. Cut worn or damaged links out         interfere with the action of the links.
of the chain and replace them with a cold-     Instead, apply a light coat of lubricant and
shut link. Close the cold-shut link and weld   store them in a dry and well-ventilated
it to equal the strength of the other links.   place.

                                         HOOKS
The two general types of hooks available                 STRENGTH OF HOOKS
are the slip hook and the grab hook (see       Hooks usually fail by straightening. Any
Figure 3-2). Slip hooks are made so that       deviation from the original inner arc indi-
the inside curve of the hook is an arc of a    cates that the hook has been overloaded.
circle and may be used with wire rope.         Since you can easily detect evidence of
chains. or fiber rope. Chain links can slip    overloading the hook. you should use a
through a slip hook so the loop formed in      hook that is weaker than the chain to
the chain will tighten under a load. Grab      which it is attached. With this system.
hooks have an inside curve that is nearly      hook distortion will occur before the chain
U-shaped so that the hook will slip over a     is overloaded. Discard severely distorted.
link of chain edgeways but will not permit     cracked. or badly worn hooks because they
the next link to slip through. Grab hooks      are dangerous. Table 3-2. page 3-4. lists
have a more limited range of use than slip     SWCs on hooks. Approximate the SWC of
hooks. They are used on chains when the        a hook by using the following rule of
loop formed with the hook is not intended to   thumb:
close up around the load.                                   2
                                                  SWC = D
                                                  D = the diameter in inches of the hook
                                                  where the inside of the hook starts its
                                                  arc (see Figure 3-3. page 3-5)
                                               Thus. the SWC of a hook with a diameter
                                               of 1 1/4 inches is as follows:
                                                             2           2
                                                  SWC=D =(1 1/4) 16 tons or 3,125
                                                  pounds

                                                          MOUSING OF HOOKS
                                               In general. always "mouse" a hook as a
                                               safety measure to prevent slings or ropes
                                               from jumping off. To mouse a hook after
                                               the sling is on the hook. wrap the wire or
                                               heavy twine 8 or 10 turns around the two
                                               sides of the hook (see Figure 3-4. page 3-5).



                                                                                Hoists 3-3
FM 5-125




Complete the process by winding several         securely. Mousing also helps prevent
turns of the wire or twine around the           straightening of the hook but does not
sides of the mousing and tying the ends         strengthen it materially.

                           INSPECTING CHAINS AND HOOKS
Inspect chains, including the hooks, at least   and cracks, sharp nicks or cuts, worn sur-
once a month; inspect those that are used       faces, and distortions. Replace those that
for heavy and continuous loading more fre-      show any of these weaknesses. If several
quently. Give particular attention to the       links are stretched or distorted, do not use
small radius fillets at the neck of hooks for   the chain; it probably was overloaded or
any deviation from the original inner arc.      hooked improperly, which weakened the
Examine each link and hook for small dents      entire chain.


3-4 Hoists
                                                                                   FM 5-125




                                  Section II. Slings
The term "sling" includes a wide variety of made of fiber rope, nor do they lose their
designs. Slings may be made of fiber rope, strength from exposure as rapidly. They
wire rope, or chain.                           also are not susceptible to the "weakest
                                               link" condition of chains caused by the
Fiber rope makes good slings because of its uncertainty of the strengths of the welds.
flexibility, but it is more easily damaged by The appearance of broken wires clearly
sharp edges on the material hoisted than are indicates the fatigue of the metal and the
wire rope or chain slings. Fiber-rope slings end of the usefulness of the sling.
are used for lifting comparatively light loads
and for temporary jobs.                        Chain slings are used especially where
                                               sharp edges of metal would cut wire rope or
Wire rope is widely used for slings because it where very hot items are lifted, as in found-
has a combination of strength and flexibility. ries or blacksmith shops.
Properly designed and appropriately fabri-
cated wire-rope slings are the safest type of Barrel slings can be made with fiber rope to
slings. They do not wear away as do slings hold barrels horizontally or vertically.
                                     TYPES OF SLINGS
The sling for lifting a given load may be--                 ENDLESS SLINGS
    An endless sling.                          The endless sling is made by splicing the
    A single sling.                            ends of a piece of wire rope or fiber rope
                                               together or by inserting a cold-shut link in a
    A combination sling (several single        chain. Cold-shut links should be welded
    slings used together).                     after insertion in the chain. These endless
Each type or combination has its particular    slings are simple to handle and may be used
advantages that must be considered when        in several different ways to lift loads (see
selecting a sling for a given purpose.         Figure 3-5, page 3-6).


                                                                                Hoists 3-5
FM 5-125




            Choker or Anchor Hitch                 the inverted basket hitch except that the
A common method of using an endless sling          line passes around toggles fastened to the
is to cast the sling under the load to be lifted   load rather than going around the load
and insert one loop through the other and          itself.
over the hoisting hook. When the hoisting
hook is raised, one side of the choker hitch is                   SINGLE SLINGS
forced down against the load by the strain
on the other side, forming a tight grip on the     A single sling can be made of wire rope, fiber
load.                                              rope, or chain. Each end of a single sling is
                                                   made into an eye or has an attached hook
                Basket Hitch                       (see Figure 3-6). In some instances, the
                                                   ends of a wire rope are spliced into the eyes
With this hitch, the endless sling is passed       that are around the thimbles, and one eye is
around the object to be lifted and both            fastened to a hook with a shackle. With this
remaining loops are slipped over the hook.         type of single sling, you can remove the
                                                   shackle and hook when desired. You can
            Inverted Basket Hitch                  use a single sling in several different ways
This hitch is very much like the simple bas-       for hoisting (see Figure 3-6). It is advisable
ket hitch except that the two parts of the         to have four single slings of wire rope avail-
sling going under the load are spread wide         able at all times. These can be used singly
apart.                                             or in combination, as necessary.

                 Toggle Hitch                                 Choker or Anchor Hitch
The toggle hitch is used only for special          A choker or anchor hitch is a single sling
applications. It is actually a modification of     that is used for hoisting by passing one eye


3-6 Hoists
                                     FM 5-125



through the other eye and over the hoisting
hook. A choker hitch will tighten down
against the load when a strain is placed on
the sling.

                Basket Hitch
A basket hitch is a single sling that is
passed under the load with both ends
hooked over the hoisting hook.

              Stone-Dog Hitch
A stone-dog hitch is single slings with two
hooks that are used for lifting stone.

            Double Anchor Hitch
This hitch is used for hoisting drums or
other cylindrical objects where it is neces-
sary for the sling to tighten itself under
strain and lift by friction against the sides of
the cylinder.

           COMBINATION SLINGS
Single slings can be combined into bridle
slings, basket slings, and choker slings to
lift virtually any type of load. Either two
or four single slings can be used in a given
combination. Where greater length is
required, two of the single slings can be com-
bined into a longer single sling. One of the
problems in lifting heavy loads is in fasten-
ing the bottom of the sling legs to the load in
such a way that the load will not be dam-
aged. Lifting eyes are fastened to many
pieces of equipment at the time it is manu-
factured. On large crates or boxes, the sling
legs may be passed under the object to form
a gasket sling. A hook can be fastened to the
eye on one end of each sling leg to permit
easier fastening on some loads. Where the
load being lifted is heavy enough or awk-
ward enough, a four-leg sling may be
required. If a still greater length of sling is
required, two additional slings can be used
in conjunction with the four-leg sling to form
a double basket.


                                   Hoists 3-7
FM 5-125


                                         PALLETS
A problem in hoisting and moving loads          the job out of 2- by 8-inch timbers that are 6
sometimes occurs when the items to be           or 8 feet long and are nailed to three or four
lifted are packaged in small boxes and the      heavy cross members, such as 4- by 8-inch
individual boxes are not crated. In this        timbers. Several pallets should be made up
case, it is entirely too slow to pick up each   so that one pallet can be loaded while the
small box and move it separately. Pallets,      pallet previously loaded is being hoisted. As
used in combination with slings, provide        each pallet is unloaded, the next return trip
an efficient method of handling such            of the hoist takes the empty pallet back for
loads. The pallets can be made up readily on    loading.

                                          SPREADERS
Occasionally, it is necessary to hoist loads that of the load, the angle of the sling leg is
are not protected sufficiently to prevent crush- changed so that crushing of the load is pre-
ing by the sling legs. In such cases, spreaders vented. Changing the angle of the sling leg
may be used with the slings (see Figure 3-7). may increase the stress in that portion of
Spreaders are short bars or pipes with eyes on the sling leg above the spreaders. The deter-
each end. The sling leg passes through the eye mining factor in computing the safe lifting
down to its connection with the load. By set- capacity of the sling is the stress (or tension)
ting spreaders in the sling legs above the top in the sling leg above the spreader.




3-8 Hoists
                                                                                    FM 5-125


                                         STRESSES
Tables 3-3 through 3-5, pages 3-10 Example: Determine the tension of a single
through 3-12, list the SWCs of ropes, leg of a two-legged sling being used to lift a
chains, and wire-rope slings under various load weighing 1,800 pounds. The length of
conditions. The angle of the legs of a sling a sling is 8 feet and the vertical distance is 6
must be considered as well as the strength of feet.
the material of which a sling is made. The
lifting capacity of a sling is reduced as the Solution:
angle of its legs to the horizontal is reduced
(as the legs of a sling are spread) (see Figure      T=
3-7). Thus, reducing the angle of the legs of
a sling increases the tension on the sling
legs. In determining the proper size of sling,       T=               1,200 pounds or 6 tons
you must determine the tension on each leg
for each load (see Figure 3-8, page 3-13). By knowing the amount of tension in a sin-
You can compute this tension using the fol-
lowing formula:                                 gle leg, you can determine the appropriate
                                                size of fiber rope, wire rope, or chain. The
                                                SWC of a sling leg (keeping within the
                                                safety factors for slings) must be equal to or
                                                greater than the tension on a sling leg. If
    T = Tension in a single sling leg (which possible, keep the tension on each sling leg
    may be more than the weight of the load below that in the hoisting line to which the
    lifted)                                     sling is attached. A particular angle formed
    W= Weight of the load to be lifted          by the sling legs with the horizontal where
                                                the tension within each sling leg equals the
    N = Number of slings                        weight of the load is called the critical angle
    L = Length of sling                         (see Figure 3-9, page 3-13). Approximate
    V = Vertical distance, measured from the    this angle using the following formula:
    hook to the top of the load
    NOTES:                                          Critical angle =
  1. L and V must be expressed in the               N = Number of sling legs
  same unit of measure.
                                                 When using slings, stay above the critical
  2. The resulting tension will be in            angle.
  the same unit of measure as that of
  the weight of the load. Thus, if the
  weight of the load is in pounds, the
  tension will be given in pounds.

                        INSPECTING AND CUSHIONING SLINGS
Inspect slings periodically and condemn 4 percent or more of the wires are broken.
them when they are no longer safe. Make Pad all objects to be lifted with wood blocks,
the usual deterioration check for fiber ropes, heavy fabric, old rubber tires, or other cush-
wire ropes, chains, and hooks when you use ioning material to protect the legs of slings
them in slings. Besides the usual precautions, from being damaged.
declare wire ropes used in slings unsafe if

                                                                                 Hoists 3-9
FM 5-125




3-10 Hoists
   FM 5-125




Hoists 3-11
FM 5-125




3-12 Hoists
   FM 5-125




Hoists 3-13
FM 5-125



                     Section III. Blocks and Tackle Systems

A force is a push or pull. The push or pull       A block consists of a wood or metal frame
that humans can exert depends on their            containing one or more rotating pulleys
weight and strength. To move any load             called sheaves (see Figure 3-10, A). A tackle
heavier than the maximum amount a per-            is an assembly of ropes and blocks used to
son can move, use a machine that multi-           multiply forces (see Figure 3-10, B). The
plies the force exerted into a force capable of   number of times the force is multiplied is
moving the load. The machine may be a             the MA of the tackle. To make up a tackle
lever, a screw, or a tackle system. The same      system, lay out the blocks you are to use to
principle applies to all of them. If you use a    be used and reeve (thread) the rope through
machine that exerts a force 10 times greater
than the force applied to it, the machine has     the blocks. Every tackle system contains a
multiplied the force input by 10. The             fixed block attached to some solid support
mechanical advantage (MA) of a machine is         and may have a traveling block attached to
the amount by which the machine multi-            the load. The single rope leaving the tackle
plies the force applied to it to lift or move a   system is called the fall line. The pulling
load. For example, if a downward push of 10       force is applied to the fall line, which may
pounds on the left end of a lever will cause      be led through a leading block. This is an
the right end of the lever to raise a load        additional block used to change the direc-
weighing 100 pounds, the lever is said to         tion of pull.
have a MA of 10.

                                        BLOCKS
Blocks are used to reverse the direction of are used where it is necessary to change
the rope in the tackle. Blocks take their    the direction of the pull on the line.
names from--
     The purpose for which they are used.                   Traveling Block
     The places they occupy.                 A traveling block is attached to the load
                                             that is being lifted and moves as the load is
     A particular shape or type of construc- lifted.
     tion (see Figure 3-11).
                                                            Standing Block
            TYPES OF BLOCKS                  This block is fixed to a stationary object.
Blocks are designated as single, double, or                     Leading Blocks
triple, depending on the number of sheaves.
                                                  Blocks used in the tackle to change the
                                                  direction of the pull without affecting the
                Snatch Block                      MA of the system are called leading blocks
This is a single sheave block made so that        (see Figure 3-12, page 3-16). In some tackle
the shell opens on one side at the base of the    systems, the fall line leads off the last block
hook to permit a rope to be slipped over the      in a direction that makes it difficult to
sheave without threading the end of it            apply the motive force required. A leading
through the block. Snatch blocks ordinarily       block is used to correct this. Ordinarily, a



3-14 Hoists
   FM 5-125




Hoists 3-15
FM 5-125



snatch block is used as the leading block.       over, remember that the rope should not
This block can be placed at any convenient       cross the rope leading away from the cen-
position. The fall line from the tackle sys-     ter sheave of the first block. Lead the rope
tem is led through the leading block to the      over the top sheave of the second block
                               -
line of most direct action.                      and back to the remaining side sheave of
                                                 the first block. From this point, lead the
                                                 rope to the center sheave of the second
                                                 block and back to the becket of the first
                                                 block. Reeve the rope through the blocks
                                                 so that no part of the rope chafes another
                                                 part of the rope.

                                                               Twisting of Blocks
                                                 Reeve blocks so as to prevent twisting.
                                                 After reeving the blocks, pull the rope back
                                                 and forth through the blocks several times
                                                 to allow the rope to adjust to the blocks.
                                                 This reduces the tendency of the tackle to
                                                 twist under a load. When the ropes in a
                                                 tackle system become twisted, there is an
                                                 increase in friction and chafing of the
                                                 ropes, as well as a possibility of jamming
             REEVING BLOCKS                      the blocks. When the hook of the standing
To prepare blocks for use, reeve, or pass a      block is fastened to the supporting member,
rope through, it. To do this, lay out the        turn the hook so that the fall line leads
blocks on a clean and level surface other        directly to the leading block or to the source
than the ground to avoid getting dirt into       of motive power. It is very difficult to pre-
the operating parts, Figure 3-13 shows the       vent twisting of a traveling block. It is par-
reeving of single and double blocks. In reev-    ticularly important when the tackle is
ing triple blocks, it is imperative that you     being used for a long pull along the ground,
put the hoisting strain at the center of the     such as in dragging logs or timbers.
blocks to prevent them from being inclined
under the strain (see Figure 3-14). If the                    Antiwisting Devices
blocks do incline, the rope will drag across
the edges of the sheaves and the shell of the    One of the simplest antitwisting devices for
block and cut the fibers. Place the blocks so    such a tackle is a short iron rod or a
that the sheaves in one block are at right       piece of pipe lashed to the traveling block
angles to the sheaves in the other block.        (see Figure 3-15, page 3-18). You can lash
You may lay the coil of rope beside either       the antitwisting rod or pipe to the shell of
block. Pass the running end over the center      the block with two or three turns of rope. If
sheave of one block and back to the bottom       it is lashed to the becket of the block, you
sheave of the other block. Then pass it over     should pass the rod or pipe between the
one of the side sheaves of the first block. In   ropes without chafing them as the tackle is
selecting which side sheave to pass the rope     hauled in.



3-16 Hoists
  FM 5-125




Hoists 3-17
FM 5-125




                                       TACKLE SYSTEMS
Tackle systems may be either simple or com-             Method I--Counting Supporting Lines
pound.
                                                     There are three lines supporting the travel-
                                                     ing block, so the theoretical MA is 3:1.
         SIMPLE TACKLE SYSTEMS
A simple tackle system uses one rope and                          Method II--Unit Force
one or more blocks. To determine the MA of
a simple system, count the number of lines            Assuming that the tension on a single rope
supporting the load (or the traveling                is the same throughout its length, a unit
block) (see Figure 3-16). In counting,               force of 1 on the fall line results in a total of
include the fall line if it leads out of a travel-   3 unit forces acting on the traveling block.
ing block. In a simple tackle system, the MA         The ratio of the resulting force of 8 on the
always will be the same as the number of             traveling block to the unit force of 1 on the
lines supporting the load. As an alternate           fall line gives a theoretical MA of 3:1.
method, you can determine the MA by trac-
ing the forces through the system. Begin                   COMPOUND TACKLE SYSTEMS
with a unit force applied to the fall line.
Assume that the tension in a single rope is          A compound tackle system uses more than
the same throughout and therefore the same           one rope with two or more blocks (see Figure
force will exist in each line. Total all the         3-18, page 3-20). Compound systems are
forces acting on the load or traveling block.        made up of two or more simple systems.
The ratio of the resulting total force acting        The fall line from one simple system is fas-
on the load or traveling block to the original       tened to a hook on the traveling block of
unit force exerted on the fall line is the theo-     another simple system, which may include
retical MA of the simple system.                     one or more blocks. In compound systems,
Figure 3-17 shows examples of two meth-              you can best determine the MA by using the
ods of determining the ratio of a simple             unit-force method. Begin by applying a unit
tackle system. They are--                            force to the fall line. Assume that the ten-
    Method I-counting supporting lines.              sion in a single rope is the same throughout
                                                     and therefore the same force will exist in
    Method II--unit force.                           each line. Total all the forces acting on the



3-18 Hoists
 FM 5-125




Hoists 3-19
FM 5-125



                                               two methods of determining the ratio of a
                                               compound tackle system. They are--
                                                    Method I--unit force.
                                                    Method II--multiplying mechanical
                                                    advantages of simple systems.

                                                            Method I--Unit Force
                                               As in method II of simple tackle systems, a
                                               unit force of 1 on the fall line results in 4
                                               unit forces acting on the traveling block of
                                               tackle system A. Transferring the unit force
                                               of 4 into the fall line of simple system B
                                               results in a total of 16 unit forces (4 lines
                                               with 4 units of force in each) acting on the
                                               traveling block of tackle system B. The ratio
                                               of 16 unit forces on the traveling block carry-
                                               ing the load to a 1 unit force on the fall line
                                               gives a theoretical MA of 16:1.

                                                       Method II--Multiplying MAs of
                                                             Simple Systems
                                               The number of lines supporting the travel-
                                               ing blocks in systems A and B is equal to 4.
                                               The MA of each simple system is therefore
                                               equal to 4:1. You can then determine the
                                               MA of the compound system by multiplying
                                               together the MA of each simple system for a
                                               resulting MA of 16:1.

                                                                  FRICTION
                                               There is a loss in any tackle system because
                                               of the friction created by--
traveling block and transfer this force into       The sheave rolling on the pin, the ropes
the next simple system. The ratio of the            rubbing together.
resulting total force acting on the load or
traveling block to the original unit force         The rope rubbing against the sheave.
exerted on the fall line is the theoretical    This friction reduces the total lifting power;
MA of the compound system. Another             therefore, the force exerted on the fall line
method, which is simpler but less accurate     must be increased by some amount to over-
in some cases, is to determine the MA of       come the friction of the system to lift the
each simple system in the compound system      load. Each sheave in the tackle system can
and multiplying these together to obtain the   be expected to create a resistance equal to
total MA. Figure 3-19 shows examples of the    about 10 percent of the weight of the load.


3-20 Hoists
FM 5-125




Hoists 3-21
FM 5-125


 Example: A load weighing 5,000 pounds is         MA of the tackle system. The actual pull
 lifted by a tackle system that has a MA of       required on the fall line would be equal to
 4:1. The rope travels over four sheaves that     the sum of 5,000 pounds (load) and 2,000
 produce a resistance of 40 percent of 5,000      pounds (friction) divided by 4 (MA) or 1,750
 pounds or 2,000 pounds (5,000 x 0.40). The       pounds.
 actual pull that would be required on the fall   There are other types of resistance that
 line of the tackle system is equal to the sum    may have to be considered in addition to
 of the weight of the load and the friction in    tackle resistance. FM 20-22 presents a
 the tackle system divided by the theoretical.    thorough discussion of resistance.

                      Section IV. Chain Hoists and Winches
In all cases where manpower is used for           tackle vertical line. If 300 pounds times
hoisting, the system must be arranged to          the MA of the system is not enough to lift
consider the most satisfactory method of          a given load, the tackle must be rigged
using that source of power. More men can          again to increase the MA, or the fall line
pull on a single horizontal line along the        must be led through a leading block to pro-
ground than on a single vertical line. On a       vide a horizontal pull. This will permit more
vertical pull, men of average weight can          people to pull on the line. Similarly, if a
pull about 100 pounds per man and about           heavy load is to be lifted and the fall line is
60 pounds per man on a horizontal. If             led through a leading block to a winch
the force required on the fall line is 300        mounted on a vehicle, the full power avail-
pounds or less, the fall line can lead            able at the winch is multiplied by the MA of
directly down from the upper block of a           the system.

                                       CHAIN HOISTS
Chain hoists provide a convenient and effi-       vertical operation are the spur gear, screw
cient method for hoisting by hand under           gear, and differential.
particular circumstances (see Figure 3-20).
The chief advantages of chain hoists are
that--                                                       Spur-Gear Chain Hoist
                                                  This is the most satisfactory chain hoist for
    The load can remain stationary with-
                                                  ordinary operation where a minimum num-
    out requiring attention.                      ber of people are available to operate the
     One person can operate the hoist to          hoist and the hoist is to be used frequently.
     raise loads weighing several tons.           This type of chain hoist is about 85 percent
                                                  efficient.
The slow lifting travel of a chain hoist per-
mits small movements, accurate adjust-                       Screw-Gear Chain Hoist
ments of height, and gentle handling of
loads. A retched-handle pull hoist is used        The screw-gear chain hoist is about 50 per-
for short horizontal pulls on heavy objects       cent efficient and is satisfactory where less
(see Figure 3-21). Chain hoists differ widely     frequent use of the chain hoist is involved.
in their MA, depending on their rated capac-
ity which may vary from 5 to 250.                            Differential Chain Hoist
        TYPES OF CHAIN HOISTS                     The differential chain hoist is only about 35
                                                  percent efficient but is satisfactory for occa-
The three general types of chain hoists for       sional use and light loads.

3-22 Hoists
                                                   FM 5-125




             LOAD CAPACITY
Chain hoists are usually stamped with their
load capacities on the shell-of the upper
block. The rated load capacity will run from
one-half of a ton upward. Ordinarily, chain
hoists are constructed with their lower hook
as the weakest part of the assembly. This
is done as a precaution so that the lower
hook will be overloaded before the chain
hoist is overloaded. The lower hook will start
to spread under overload, indicating to the
operator that he is approaching the over-
load point of the chain hoist. Under ordinary


                                                 Hoists 3-23
FM 5-125


circumstances, the pull exerted on a chain         the chain are distorted, it indicates that
hoist by one or two men will not overload          the chain hoist has been heavily over-
the hoist. Inspect chain hoists at frequent        loaded and is probably unsafe for further
intervals. Any evidence of spreading of            use. Under such circumstances, the chain
the hook or excessive wear is sufficient           hoist should be condemned.
cause to replace the hook. If the links of

                                           WINCHES
Vehicular-mounted and engine-driven                overwound or underwound on the drum as
winches are used with tackles for hoisting         may be necessary to avoid a reverse bend.
(see Figure 3-22). There are two points to
consider when placing a power-driven winch                        FLEET ANGLE
to operate hoisting equipment. They are--
                                                   The drum of the winch is placed so that a
     The angle with the ground that the            line from the last block passing through the
     hoisting line makes at the drum of the        center of the drum is at right angles to the
     hoist.                                        axis of the drum. The angle between this
                                                   line and the hoisting line as it winds on the
     The fleet angle of the hoisting line          drum is called the fleet angle (see Figure
     winding on the drum (see Figure 3-23).        3-23). As the hoisting line is wound in on
The distance from the drum to the first            the drum, it moves from one flange to the
sheave of the system is the controlling factor     other so that the fleet angle changes during
in the fleet angle. When using vehicular-          the hoisting process. The fleet angle should
mounted winches, place the vehicle in a            not be permitted to exceed 2 degrees and
                                                   should be kept below this, if possible. A 1 1/
position that lets the operator watch the          2-degree maximum angle is satisfactory and
load being hoisted. A winch is most effective      will be obtained if the distance from the
when the pull is exerted on the bare drum of       drum to the first sheave is 40 inches for
the winch. When a winch is rated at a capac-       each inch from the center of the drum to the
ity, that rating applies only as the first layer   flange. The wider the drum of the hoist the
of cable is wound onto the drum. The winch         greater the lead distance must be in placing
capacity is reduced as each layer of cable is      the winch.
wound onto the drum because of the change
in leverage resulting from the increased
diameter of the drum. The capacity of the
winch may be reduced by as much as 50 per-
cent when the last layer is being wound onto
the drum.

              GROUND ANGLE
If the hoisting line leaves the drum at an
angle upward from the ground, the result-
ing pull on the winch will tend to lift it
clear of the ground. In this case, a leading
block must be placed in the system at some
distance from the drum to change the direc-
tion of the hoisting line to a horizontal or
downward pull. The hoisting line should be

3-24 Hoists
                                                   FM 5-125



            SPANISH WINDLASS
In the absence of mechanical power or an
appropriate tackle, you may have to use
makeshift equipment for hoisting or pulling.
You can use a Spanish windlass to move a
load along the ground, or you can direct the
horizontal pull from the windlass through
the blocks to provide a vertical pull on a
load. In making a Spanish windlass, fasten
a rope between the load you are to move and
an anchorage some distance away. Place a
short spar vertically beside this rope, about
halfway between the anchorage and the load
(see Figure 3-24, page 3-26). This spar may
be a pipe or a pole, but in either case it
should have as large a diameter as possible.
Make a loop in the rope and wrap it partly
around the spar. Insert the end of a horizon-
tal rod through this loop. The horizontal rod
should be a stout pipe or bar long enough to
provide leverage. It is used as a lever to
turn the vertical spar. As the vertical spar
turns, the rope is wound around it, which
shortens the line and pulls on the load.
Make sure that the rope leaving the vertical
spar is close to the same level on both sides
to prevent the spar from tipping over.




                                                Hoists 3-25
FM 5-125




3-26 Hoists
                                                                                  FM 5-125




                                   CHAPTER           4


                  A n c h o r s and             Guy        Lines


                                Section I. Anchors
When heavy loads are handled with a            anchorages should be used so that time,
tackle, it is necessary to have some means     effort, and material can be conserved. The
of anchorage. Many expedient rigging           ideal anchorage system must be of suffi-
installations are supported by combining       cient strength to support the breaking
guy lines and some type of anchorage sys-      strength of the attached line. Lines should
tem. Anchorage systems may be either nat-      always be fastened to anchorages at a
ural or man-made. The type of anchorage        point as near to the ground as possible.
to be used depends on the time and mate-       The principal factor in the strength of most
rial available and on the holding power        anchorage systems is the area bearing
required. Whenever possible, natural           against the ground.

                                    NATURAL ANCHORS
Trees, stumps, or rocks can serve as          between two trees to provide a stronger
natural anchorages for rapid work in          anchorage than a single tree (see Fig-
the field. Always attach lines near the       ure 4-2, page 4-2). When using rocks as
ground level on trees or stumps (see Fig-     natural anchorages, examine the rocks
ure 4-1. Avoid dead or rotten trees or        carefully to be sure that they are large
stumps as an anchorage because they are       enough and firmly embedded in the
likely to snap suddenly when a strain is      ground (see Figure 4-3, page 4-2). An out-
placed on the line. It is always advisable to cropping of rock or a heavy boulder buried
lash the first tree or stump to a second one  partially in the ground will serve as a sat-
to provide added support. Place a transom     is factory anchor.




                                                             Anchors and Guy Lines 4-1
FM 5-125




                            MAN-MADE ANCHORS
You must construct man-made anchors     5 inches deep. Use a l-inch-diameter drill
when natural anchors are not available. for hard rock and a 3/4-inch-diameter drill
These include--                         for soft rock. Drill the hole as neatly as
                                        possible so that the rock anchor can
    Rock anchors.                       develop the maximum strength. In case of
    Picket holdfasts.                   extremely soft rock, it is better to use some
                                        other type of anchor because the wedging
    Combination holdfasts.              action may not provide sufficient holding
    Deadmen.                            power.

               ROCK ANCHORS
Rock anchors have an eye on one end and a
threaded nut, an expanding wedge, and a
stop nut on the other end (see Figure 4-4).
To construct a rock anchor, insert the
threaded end of the rock anchor in the hole                     .
with the nut's relation to the wedge as
shown in Figure 4-4. After placing the an-
chor, insert a crowbar through the eye of the
rock anchor and twist it. This causes the
threads to draw the nut up against the
wedge and force the wedge out against the
sides of the hole in the rock. The wedging
action is strongest under a direct pull;
therefore, always set rock anchors so that
the pull is in a direct line with the shaft of
the anchor. Drill the holes for rock anchors


4-2 Anchors and Guy Lines
                                                                 FM 5-125



            PICKET HOLDFASTS
A single picket, either steel or wood, can be
driven into the ground as an anchor. The
holding power depends on the--
     Diameter and kind of material used.
     Type of soil.
     Depth and angle in which the picket is
     driven.
     Angle of the guy line in relation to the
     ground.
Table 4-1 lists the holding capacities of the
various types of wooden picket holdfasts.
Figure 4-5 shows the various picket hold-
fasts.




                                                Anchors and Guy Lines 4-3
FM 5-125



           Single Wooden Pickets                   first picket to the bottom of the second
                                                   picket (see Figure 4-6, B). Then fasten the
Wooden stakes used for pickets should be at        rope to the second picket with a clove hitch
least 3 inches in diameter and 5 feet long.        just above the turns. Put a stake between
Drive the picket 3 feet into the ground at an
angle of 15 degrees from the vertical and          the rope turns to tighten the rope by twist-
inclined away from the direction of pull (see      ing the stake and then driving it into the
Figure 4-6).                                       ground (see Figure 4-6, C). This distributes
                                                   the load between the pickets. If you use
                                                   more than two pickets, make a similar lash-
          Multiple Wooden Pickets                  ing between the second and third pickets
You can increase the strength of a holdfast        (see Figure 4-6, D). If you use wire rope for
by increasing the area of the picket bearing       lashing, make only two complete turns
against the ground. Two or more pickets            around each pair of pickets. If neither fiber
driven into the ground, spaced 3 to 6 feet         rope nor wire rope is available for lashing,
apart and lashed together to distribute the        place boards from the top of the front picket
load, are much stronger than a single picket       to the bottom of the second picket and nail
(see Figure 4-6, A). To construct the lashing,     them onto each picket (see Figure 4-7). As
tie a clove hitch to the top of the first picket   you place pickets farther away from the
with four to six turns around the first and        front picket, the load to the rear pickets is
second pickets, leading from the top of the        distributed more unevenly. Thus, the prin-




4-4 Anchors and Guy Lines
                                                                                      FM 5-125




cipal strength of a multiple-picket holdfast     pattern. Drive the rear pickets in first to
is at the front pickets. Increase the capacity   secure the end of the chain; then, install the
of a holdfast by using two or more pickets to    successive pickets so that there is no slack
form the front group. This increases both        in the chain between the pickets. A lashed
the bearing surface against the soil and the     steel-picket holdfast consists of steel pickets
BS.                                              lashed together with wire rope the same as
                                                 for a wooden-stake picket holdfast (see Fig-
                                                 ure 4-9, page 4-6). As an expedient, any mis-
            Steel-Picket Holdfasts               cellaneous light-steel members can be
A standard steel-picket holdfast consists of     driven into the ground and lashed together
a steel box plate with nine holes drilled        with wire rope to form an anchorage.
through it and a steel eye welded on the end
for attaching a guy line (see Figure 4-8, page                  Rock Holdfasts
4-6). The pickets are also steel and are
driven through the holes in a way that           You can place a holdfast in rock by drilling
clinches the pickets in the ground. This         into the rock and driving the pickets into the
holdfast is especially adapted for anchoring     holes. Lash the pickets together with a
horizontal lines, such as the anchor cable on    chain (see Figure 4-10, page 4-7). Drill the
a ponton bridge. Use two or more of these        holes about 3 feet apart, in line with the guy
units in combination to provide a stronger       line. The first, or front, hole should be 2 1/2
anchorage. You can improvise a similar           to 3 feet deep and the rear hole, 2 feet deep.
holdfast with a chain by driving steel pick-     Drill the holes at a slight angle, inclined
ets through the chain links in a crisscross      away from the direction of the pull.



                                                                Anchors and Guy Lines 4-5
FM 5-125




        COMBINATION HOLDFASTS                                     Construction
For heavy loading of an anchorage, spread        You can construct a deadman from a log, a
the load over the largest possible area of       rectangular timber, a steel beam, or a simi-
ground. Do this by increasing the number of      lar object buried in the ground with a guy
pickets used. Place four or five multiple        line or sling attached to its center. This guy
picket holdfasts parallel to each other with a   line or sling leads to the surface of the
heavy log resting against the front pickets to   ground along a narrow upward sloping
form a combination log and picket holdfast       trench. The holding power of a deadman is
(see Figure 4-11). Fasten the guy line or        affected by--
anchor sling to the log that bears against the
pickets. The log should bear evenly against           Its frontal bearing area.
all pickets to obtain maximum strength.              Its mean (average) depth.
Select the timber carefully so it can with-
stand the maximum pull on the line without
appreciable bending. Also, you could use a
steel cross member to form a combination
steel-picket holdfast (see Figure 4-12, page
4-8).

                DEADMEN
A deadman is one of the best types of
anchorages for heavy loads or permanent
installations because of its great holding
power.



4-6 Anchors and Guy Lines
                                                                                FM 5-125




    The angle of pull.                        withstand the BS of the line attached to it.
                                              In constructing a deadman, dig a hole at
    The deadman material.                     right angles to the guy line and undercut 15
     The soil condition.                      degrees from the vertical at the front of the
                                              hole facing the load (see Figure 4-13, page
The holding power increases progressively     4-8). Make the guy line as horizontal as pos-
as you place the deadman deeper and as the    sible, and ensure that the sloping trench
angle of pull approaches a horizontal posi-   matches the slope of the guy line. The main
tion (see Table 4-2, page 4-8). The holding   or standing part of the line leads from the
power of a deadman must be designed to        bottom of the deadman. This reduces the




                                                            Anchors and Guy Lines 4-7
FM 5-125




tendency to rotate the deadman upward out        the wire-rope clips above the ground for
of the hole. If the line cuts into the ground,   retightening and maintenance.
place a log or board under the line at the
outlet of the sloping trench. When using                            Terms
wire-rope guy lines with a wooden dead-
man, place a steel bearing plate on the          Table 4-3 lists the terms used in designing a
deadman where the wire rope is attached to       deadman.
avoid cutting into the wood. Always place




4-8 Anchors and Guy Lines
                                                                                  FM 5-125




                 Formulas                    Given: l-inch-diameter 6-by-19 IPS rope
The following formulas are used in designing
a deadman:                                     MD = 7 feet


     B Ar = B S
             HP                                 SR = 1.3

          BA r
     E L = D                                    WST = 2 feet


     TL = EL+ WST                                 Requirement I: Determine the length
                                                  and thickness of a rectangular timber
             D                                    deadman if the height of the face avail-
     VD= MD+ 2                                    able is 18 inches (1 1/2 feet).

          VD                                      BS of wire rope = 83,600 psf (see Table
     HD = S R                                     1-2)

                                                  HP= 8,000 psf (see Table 4-2)
A sample problem for designing a deadman
is as follows:


                                                               Anchors and Guy Lines 4-9
FM 5-125



   Note: Design the deadman so it can                 to or less than 5. The ratio for Requirement
   withstand a tension equal to the                   II would be equal to L/d = 6.2/2.5 = 2.5.
   BS of the wire rope                                Since this is less than 5, the log will not fail
                                                      by bending.
      BA r       BS = 83,600 pounds               2
             =
                                    = 10.5 feet                 Length-to-Diameter Ratio
                     HP 8,000 psf
                                                      If the length-to-diameter ratios for a log or a
                                                      rectangular timber are exceeded, you must
                   BA r
                      = 10.5 feet2                    decrease the length requirements. Use one
                                   = 7 feet
     EL = face height    1.5 feet                     of the following methods to accomplish this:
                                                           Increase the mean depth.
     TL = EL + WST = 7 feet + 2 feet = 7 feet
                                                           Increase the slope ration (the guy line
                                                           becomes more horizontal).
Conduct a final check to ensure that the                   Increase the thickness of the deadman.
rectangular timber will not fail by bending
by doing a length-to-thickness ratio (L/t),                Decrease the width of the sloping
which should be equal to or less than 9.                   trench, if possible.
Determine the minimum thickness by L/t =
9 and solve for (t):
                                                          NOMOGRAPH-DESIGNED DEADMEN
     L 9                                              Nomography and charts have been prepared
     --=                                              to facilitate the design of deadmen in the
     1t
                                                      field. The deadmen are designed to resist
     9=9                                              the BS of the cable. The required length and
     t                                                thickness are based on allowable soil bear-
                                                      ing with 1-foot lengths added to compensate
       9 = l feet
      =-                                              for the width of the cable trench. The
       9                                              required thickness is based on a L/d ratio of
                                                      s for logs and a L/d ratio of 9 for cut timber.
Thus, an 18-inch by 12-inch by 9-foot timber
is suitable.                                                          Log Deadman
     Requirement II: Determine the length             A sample problem for designing a log dead-
     of a log deadman with a diameter of 2            man is as follows:
     1/2 feet.                                             Given: 3/4-inch IPS cable. You must
                           2
            BAr = 10.5feet                                 bury the required deadman 5 feet at a
     EL = D       2.5 feet = 4.2 feet                      slope of 1:4.
                                                           Solution: With this information,
     TL = EL + WST = 4.2 feet + 2 feet = 6.2 feet          use the nomograph to determine the
                                                           diameter and length of the deadman
                                                           required (see Figure 4-14). Figure 4-15,
Conduct a final check to ensure that the log               page 4-12, shows the steps, graphi-
will not fail by bending by doing a length-to-             cally, on an incomplete nomograph.
diameter ratio (L/d), which should be equal                Lay a straightedge across section A-A


4-10 Anchors and Guy Lines
                                                                         FM 5-125



(left-hand scale) on the 5-foot depth at   up from the intersection on the log and
deadman and 1:4 slope and on 3/4-inch      read the length of deadman required. In
IPS on B-B. Read across the straightedge   this case, the deadman must be over 5
and locate a point on section C-C. Then    1/2 feet long. Be careful not to select a
go horizontally across the graph and       log deadman in the darkened area of
intersect the diameter of the log dead-    the nomograph because a log from this
men available. Assume that a 30-inch       area will fail by bending.
diameter log is available. Go vertically




                                                   Anchors and Guy Lines 4-11
FM 5-125




4-12 Anchors and Guy Lines
                                                                                               FM 5-125



       Rectangular Timber Deadman
                                                             deadman depth = 7ft = 28ft
A sample problem for designing a rectangu-                     slope ratio   1:4
lar timber deadman is as follows:
      Given: 3/4-inch IPS cable. You are to                            BEARING PLATES
      bury the deadman 5 feet at a slope of
      1:4.                                                To prevent the cable from cutting into the
                                                          wood, place a metal bearing plate on the
     Solution: Use the same 1:4 slope and                 deadman. The two types of bearing plates
     5-foot depth, along with the procedure               are the flat bearing plate and the formed
     to the left of the graph, as in the                  bearing plate, each with its particular
     previous problem (see Figure 4-14, page              advantages. The flat bearing plate is easily
     4-11). At C-C, go horizontally across                fabricated, while the formed or shaped plate
     the graph to the timber with an 18-inch              can be made of much thinner steel.
     face. Reading down (working with cut
     timber), you can see that the length is 8                           Flat Bearing Plate
     feet 6 inches and that the minimum                   A sample problem in the design of flat bear-
     thickness is 11 1/2 inches. None of the
                                                          ing plates is as follows:
     timber sizes shown on the nomograph
     will fail due to bending.                                 Given: 12-inch by 12-inch timber
                                                               3/4-inch IPS cable
             Horizontal Distance                               Solution: Enter the graph (see Figure
Use the following formula to determine the                     4-16, page 4-14) from the left of the 3/4-
distance behind the tower in which deadmen                     inch cable and go horizontally across
are placed:                                                    the graph to intersect the line marked
                                                               12-inch timber, which shows that the
                                                               plate will be 10 inches wide. (The bear-
Horizontal distance = tower height + deadman depth             ing plate is made 2 inches narrower
                                slope ratio                    than the timber to prevent cutting into
                                                               the anchor cable.) Drop vertically and
A sample problem for determining the hori-                     determine the length of the plate,
zontal distance behind a tower is as follows:                  which is 9 1/2 inches. Go to the top,
     Given: The tower height is 25 feet 4 1/4                  vertically along the line to where it
     inches, and the deadman depth is 7 feet                   intersects with 3/4-inch cable, and
     with a 1:4 slope.                                         determine the minimum required
                                                               thickness, which is 1 1/16 inches.
                                                               Thus, the necessary bearing plate must
     Solution:                                                 be 1 1/16 inches by 9 1/2 inches by 10
                                                               inches.
    25 ft 4 1/4 in + 7 ft = 32ft 4 1/4 in = 129 ft 5 in
            1:4                  1:4                                  Formed Bearing Plate
                                                          The formed bearing plates are either curved
Place the deadman 129 feet behind the                     to fit logs or formed to fit rectangular tim-
tower.                                                    ber. In the case of a log, the bearing plate
  Note:    The horizontal distance                        must go half way (180 degrees) around the
   without a tower is as follows:                         log. For a shaped timber, the bearing plate


                                                                        Anchors and Guy Lines 4-13
FM 5-125




4-14 Anchors and Guy Lines
                                                                                  FM 5-125



extends the depth of the timber with an           inches. If you use a log, the width of
extended portion at the top and the bottom        the bearing plate is equal to half the
(see Figure 4-17). Each extended portion          circumference of the log.
should be half the depth of the timber.
A sample problem for designing a formed           d     in this case, 22 inches
bearing plate is as follows:                      2
    Given: 14-inch log or timber with 14-inch
    face and 1 1/8 MPS cable.                    d
                                                 --=  3.14 x 14 = 21.98 (use 22 inches)
                                                 2        2
    Solution: Design a formed bearing The bearing plate would therefore be 1/4
    plate. Enter the graph on the left at 1 inch by 12 inches by 22 inches. For a rectan-
    1/8 MPS and go horizontally across to
    intersect the 14-inch line (see figure gular timber, the width of the plate would be
    4-17). Note that the lines intersect in 14 inches for the face and 7 inches for the
    an area requiring a l/4-inch plate. width of each leg, or a total width of 28
    Drop vertically to the bottom of the inches (see Figure 4-17). The bearing plate
    graph to determine the length of the would therefore be 1/4 inch by 12 inches by
    plate, which in this instance is 12 28 inches.




                                                          Anchors and Guy Lines 4-15
FM 5-125


                                Section II. Guy Lines
Guy lines are ropes or chains attached to an           Angle of the guy line.
object to steady, guide, or secure it. The       For example, if the supported structure is
lines leading from the object or structure are
                                                 vertical, the stress on each guy line is very
attached to an anchor system (see Fig-           small; but if the angle of the structure is 45
ure 4-18). When a load is applied to the         degrees, the stress on the guy lines support-
structure supported by the guy lines, a por-
                                                 ing the structure will increase considerably.
tion of the load is passed through each sup-
                                                 Wire rope is preferred for guy lines because
porting guy line to its anchor. The amount       of its strength and resistance to corrosion.
of tension on a guy line depends on the--        Fiber is also used for guy lines, particularly
     Main load.                                  on temporary structures. The number and
                                                 size of guy lines required depends on the
     Position and weight of the structure.       type of structure to be supported and the
     Alignment of the guy line with the          tension or pull exerted on the guy lines
     structure and the main load.                while the structure is being used.




4-16 Anchors and Guy Lines
                                                                                              FM 5-125



                              NUMBER OF GUY LINES
Usually a minimum of four guy lines are points in a tiered effect. In such cases,
used for gin poles and boom derricks and there might be four guy lines from the
two for shears. The guy lines should be center of a long pole to anchorage on
evenly spaced around the structure. In a the ground and four additional guy
long, slender structure, it is sometimes lines from the top of the pole to anchor-
necessary to provide support at several age on the ground.

                                   TENSION ON GUY LINES
You must determine the tension that will be            Given:      WL = 2,400 lb
exerted on the guy lines beforehand to select                      W 3 = 800 lb
the proper size and material you will use.                         D = 20
The maximum load or tension on a guy line
will result when a guy line is in direct line          Solution:
with the load and the structure. Consider
this tension in all strength calculations of               ( WL + 1/2W3) D       (2,400 + 1/2 (800)) 20
                                                     T =                     =


guy lines. You can use the following formula                      Y                        28
to determine the tension for gin poles and
shears (see Figure 4-19, page 4-18):                   = 2,000 pounds of tension in the rear
                                                          or supporting guy line

T = (WL + 1/2W3) D
          Y
T = Tension in guy line                                Requirement II: shears.

W L = Weight of the load                               Given: The same conditions exist as in
                                                       Requirement I except that there are
W 3 = Weight of spar(s)                                two spars, each one weighing 800
                                                       pounds.
D = Drift distance, measured from the base of
the gin pole or shears to the center of the sus-       Solution:
pended load along the ground.
                                                           (W L + 1/2W3)D)   =   (2, 400 + 1/2 (800)) 20
                                                     T =
Y= Perpendicular distance from the rear guy                        Y                         Y
line to the base of the gin pole or, for a shears,   = 2,285 pounds
to a point on the ground midway between the
shear legs.
A sample problem for determining the ten-            NOTE: The shears produced a
sion for gin poles and shears follows:               greater tension in the rear guy
                                                     line due to the weight of an addi-
     Requirement I: gin pole.                        tional spar.




                                                                   Anchors and Guy Lines 4-17
FM 5-125




                                     SIZE OF GUY LINES
The size of the guy line to use will depend on must incorporate the appropriate FSs.
the amount of tension placed on it. Since Therefore, choose a rope for the guy line
the tension on a guy line may be affected by that has a SWC equal to or greater than the
shock loading (and its strength affected by tension placed on the guy line.
knots, sharp bends, age, and condition), you

                             ANCHORAGE REQUIREMENTS
An ideal anchorage system should be least a 1-1 combination (1,400-pound capac-
designed to withstand a tension equal to the it y in ordinary soil). Anchor the guy line as
BS of the guy line attached to it. If you use a far as possible from the base of the installa-
3/8-inch-diameter manila rope as a guy line, tion to obtain a greater holding power from
the anchorage must be capable of withstand- the anchorage system. The recommended
ing a tension of 1,350 pounds, which is the minimum distance from the base of the
BS of the 3/8-inch diameter manila rope. If installation to the anchorage for the guy line
you use picket holdfasts, you will need at is twice the height of the installation.




4-18 Anchors and Guy Lines
                                                                                    FM 5-125




                                     CHAPTER 5


            Lifting          and        Moving            Equipment


                            Section I. Lifting Equipment
Equipment used for lifting includes gin          includes pole, brave, and jinniwink der-
poles, tripods, shears, boom derricks, and       ricks.
stiff leg derricks. Light hoisting equipment

                                         GIN POLES
A gin pole consists of an upright spar that is spruce timbers as gin poles, with allow-
guyed at the top to maintain it in a vertical  ances for normal stresses in hoisting oper-
or nearly vertical position and is equipped    ations.
with suitable hoisting tackle. The vertical
spar may be of timber, a wide-flange steel-                RIGGING GIN POLES
beam section, a railroad rail, or similar
members of sufficient strength to support      In rigging a gin pole, lay out the pole with
the load being lifted. The load may be         the base at the spot where it is to be
hoisted by hand tackle or by hand- or          erected. To make provisions for the guy
engine-driven hoists. The gin pole is used     lines and tackle blocks, place the gin
widely in erection work because of the ease    pole on cribbing for ease of lashing. Figure
with which it can be rigged, moved, and        4-18, page 4-16, shows the lashing on top of
operated. It is suitable for raising loads of  a gin pole and the method of attaching
medium weight to heights of 10 to 50 feet      guys. The procedure is as follows:
where only a vertical lift is required. The
gin pole may also be used to drag loads hori-        Make a tight lashing of eight turns of
zontally toward the base of the pole when            fiber rope about 1 foot from the top of
preparing for a vertical lift. It cannot be          the pole, with two of the center turns
drifted (inclined) more than 45 degrees from         engaging the hook of the upper block
the vertical or seven-tenths the height of           of the tackle. Secure the ends of the
the pole, nor is it suitable for swinging the        lashing with a square knot. Nail
load horizontally. The length and thickness          wooden cleats (boards) to the pole
of the gin pole depends on the purpose for           flush with the lower and upper sides
which it is installed. It should be no longer        of the lashing to prevent the lashing
than 60 times its minimum thickness                  from slipping.
because of its tendency to buckle under com-
pression. A usable rule is to allow 5 feet of        Lay out guy ropes, each four times the
pole for each inch of minimum thickness.             length of the gin pole. In the center of
Table 5-1, page 5-2, lists values when using         each guy rope, form a clove hitch over


                                                        Lifting and Moving Equipment 5-1
FM 5-125




    the top of the pole next to the tackle           the lashing on the leading block and
    lashing. Be sure to align the guy lines          near the bottom of the pole. This pre-
    in the direction of their anchors (see           vents the pole from skidding while you
    Figure 5-1).                                     erect it.
    Lash a block to the gin pole about 2 feet        Check all lines to be sure that they are
    from the base of the pole, the same as           not snarled. Check all lashings to see
    for the tackle lashing at the top, and           that they are made up properly and
    place a cleat above the lashing to pre-          that all knots are tight. Check the
    vent slipping. This block serves as a            hooks on the blocks to see that they are
    leading block on the fall line, which            moused properly. You are now ready
    allows a directional change of pull from         to erect the gin pole.
    the vertical to the horizontal. A snatch
    block is the most convenient type to use               ERECTING GIN POLES
    for this purpose.
                                                You can easily raise a 40-foot-long gin pole
    Reeve the hoisting tackle, and use the      by hand (see Figure 5-2). However, you
    block lashed to the top of the pole so      must raise longer poles by supplementary
    that the fall line can be passed through    rigging or power equipment. The number of
    the leading block at the base of the gin    people needed to erect a gin pole depends on
    pole.                                       the weight of the pole. The procedure is as
                                                follows:
    Drive a stake about 3 feet from the
    base of the gin pole. Tie a rope from             Dig a hole about 2 feet deep for the
    the stake to the base of the pole below           base of the gin pole.


5-2 LIftlng and Moving Equipment
                      FM 5-125




Lifting and Moving Equipment 5-3
FM 5-125



     String out the guys to their respective          throwing all of its weight on one of the
     anchorages and assign a person to each           side guys.
     anchorage to control the slack in the
     guy line with a round turn around the            Fasten all guy lines to their anchor-
     anchorage as the pole is raised. If it           ages with the round turn and two half
     has not been done already, install an            hitches when the pole is in its final
     anchorage for the base of the pole.              position, approximately vertical or
                                                      inclined as desired. At times, you may
    Use the tackle system that was used to            have to double the portion of rope used
    raise and lower the load to assist in             for the half hitches.
    raising the gin pole, if necessary; how-
    ever, the preferred method is to attach           Open the leading block at the base of
    an additional tackle system to the rear           the gin pole and place the fall line from
    guy line. Attach the running block of             the tackle system through it. When
    the rear guy-line tackle system to the            the leading block is closed, the gin pole
    rear guy line, the end of which is at this        is ready for use. If you have to drift
    point of erection near the base of the            the top of the pole without moving the
    gin pole (see Figure 4-18, page 4-16).            base, do it when there is no load on
    Secure the fixed or stationary block to           the pole, unless the guys are equipped
    the rear anchor. The fall line should             with tackle.
    come out of the running block to give
    greater MA to the tackle system.                        OPERATING GIN POLES
    Stretch the tackle system to the base of
    the gin pole before erecting it to pre-      The gin pole is particularly adapted to verti-
    vent the tackle blocks from chocking.        cal lifts (see Figure 5-3). Sometimes it is
                                                 used for lifting and pulling at the same time
    Haul in on the fall line of the tackle       so that the load being moved travels toward
    system, keeping a slight tension on the      the gin pole just off the ground. When used
    rear guy line and on each of the side        in this manner, attach a snubbing line of
    guy lines, while eight people (more for      some kind to the other end of the load being
    larger poles) raise the top of the pole by   dragged; keep it under tension at all times.
    hand until the tackle system can take        Use tag lines to control loads that you are
    control (see Figure 5-2, page 5-3).          lifting vertically. A tag line is a light line
    Keep the rear guy line under tension to      fastened to one end of the load and kept
    prevent the pole from swinging and           under slight tension during hoisting.


                                          TRIPODS
A tripod consists of three legs lashed or one-half times that of shears made of the
secured at the top. The advantage of the tri- same size material.
pod over other rigging installations is that
it is stable and requires no guy lines to
hold it in place. Its disadvantage is that the           RIGGING TRIPODS
load can be moved only up and down. The The two methods of lashing a tripod, either
load capacity of a tripod is about one and of which is suitable provided the lashing


5-4 Lifting and Moving Equipment
                     FM 5-125




Lifting and Moving Equipment 5-5
FM 5-125



material is strong enough, are discussed
below. The material used for lashing can be
fiber rope, wire rope, or chain. Metal rings
joined with short chain sections and large
enough to slip over the top of the tripod legs
also can be used.

                  Method 1
This method is for fiber rope, 1 inch in diam-
eter or smaller. Since the strength of the tri-
pod is affected directly by the strength of the
rope and the lashing used, use more turns
than described here for extra heavy loads
and fewer turns for light loads. The proce-
dure is as follows:
     Select three spars, about equal in size,
     and place a mark near the top of each
     to indicate the center of the lashing.
     Lay two of the spars parallel with their
     tops resting on a skid or block and a
     third spar between the first two, with
     the butt in the opposite direction and
     the lashing marks on all three in line.
     The spacing between spars should be
     about one-half the diameter of the
     spars. Leave space between the spars
     so that the lashing will not be drawn
     too tight when erecting the tripod.                             Method H
     Make a clove hitch (using a l-inch           You can use this method when using slender
                                                  poles that are not more than 20 feet long or
     rope) around one of the outside spars        when some means other than hand power is
     about 4 inches above the lashing mark,       available for erection (see figure 5-4, B). The
     and take eight turns of the line around      procedure is as follows:
     the three spars (see Figure 5-4, A). Be
     sure to maintain the space between the            Lay the three spars parallel to each
     spars while making the turns.                     other with an interval between them
                                                       slightly greater than twice the diame-
     Finish the lashing by taking two close            ter of the rope you use. Rest the tops of
     frapping turns around the lashing                 the poles on a skid so that the ends
     between each pair of spars. Secure the            project over the skid about 2 feet and
     end of the rope with a clove hitch on             the butts of the three spars are in line.
     the center spar just above the lashing.           Put a clove hitch on one outside leg at
     Do not draw the frapping turns too                the bottom of the position that the lash-
     tight.                                            ing will occupy, which is about 2 feet


5-6 Lifting and Moving Equipment
                                                                                      FM 5-125



     from the end. Weave the line over the
     middle leg, under and around the outer
     leg, under the middle leg, and over and
     around the first leg; continue this
     weaving for eight turns. Finish with a
     clove hitch on the outer leg.

            ERECTING TRIPODS
Spread the legs of a tripod in its final posi-
tion so that each leg is equidistant from the
others (see Figure 5-5). This spread should
not be less than one-half nor more than two-
thirds of the length of the legs. Use chain,
rope, or boards to hold the legs in this posi-
tion. You can lash a leading block for the fall
line of the tackle to one of the legs. The pro-
cedure is as follows:
     Raise the tops of the spars about 4 feet,
     keeping the base of the legs on the
     ground.
     Cross the two outer legs. The third or
     center leg then rests on top of the cross.
     With the legs in this position, pass a
     sling over the cross so that it passes
     over the top or center leg and around
     the other two.
     Hook the upper block of a tackle to the
     sling and mouse the hook.
     Continue raising the tripod by pushing
     in on the legs as they are lifted at the
     center. Eight people should be able to
     raise an ordinary tripod into position.
     Place a rope or chain lashing between
     the tripod legs to keep them from shift-     (with the three legs laid together) by raising
     ing once they are in their final position.   the tops of the legs until the legs clear the
                                                  ground so they can be spread apart. Use
                                                  guy lines or tag lines to assist in steadying
        ERECTING LARGE TRIPODS                    the legs while raising them. Cross the outer
For larger tripod installations, you may have     legs so that the center leg is on top of the
to erect a small gin pole to raise the tripod     cross, and pass the sling for the hoisting
into position. Erect the tripods that are         tackle over the center leg and around the
lashed in the manner described in Method II       two outer legs at the cross.



                                                          Lifting and Moving Equipment 5-7
FM 5-125


                                            SHEARS
Shears made by lashing two legs together             the legs at this point should be equal to
with a rope are well adapted for lifting             one-third the diameter of one leg to
heavy machinery or other bulky loads. They           make handling of the lashing easier.
are formed by two members crossed at their
tops, with the hoisting tackle suspended             With sufficient l-inch rope for 14 turns
from the intersection. Shears must be                around both legs, make a clove hitch
guyed to hold them in position. Shears are           around one spar and take eight turns
quickly assembled and erected. They                  around   both legs above the clove hitch
require only two guys and are adapted to             (see Figure 5-6). Wrap the turns
working at an inclination from the vertical.         tightly  so that the lashing is smooth
The legs of the shears may be round poles,           and  without   kinks.
timbers, heavy planks, or steel bars, depend-        Finish the lashing by taking two frap-
ing on the material at hand and the purpose
                                                     ping turns around the lashing between
of the shears. In determining the size of the
members to use, the load to be lifted and the        the legs and securing the end of the
ratio (L/d) of the legs are the determining          rope to the other leg just below the
factors. For heavy loads, the L/d should not         lashing.   For handling heavy loads,
exceed 60 because of the tendency of the legs        increase  the  number of lashing turns.
to bend rather than to act as columns. For
light work, you can improvise shears from                   ERECTING SHEARS
two planks or light poles bolted together and
reinforced by a small lashing at the intersec-  Dig the holes at the points where the legs of
tion of the legs.                               the shears are to stand. If placed on rocky
                                                ground, make sure that the base for the
                                                shears is level. Cross the legs of the shears
              RIGGING SHEARS                    and place the butts at the edges of the holes.
When the shears are erected, the spread of With a short length of rope, make two turns
the legs should equal about one-half the over the cross at the top of the shears and tie
height of the shears. The maximum allow- the rope together to form a sling. Be sure to
able drift is 45 degrees. Tackle blocks and have the sling bearing against the spars and
guys for shears are essential. You can not on the shears lashing entirely. The pro-
secure the guy ropes to firm posts or trees cedure is as follows:
with a turn of the rope so that the length of
the guys can be adjusted easily. The proce-          Reeve a set of blocks and place the
dure is as follows:                                  hook of the upper block through the
      Lay two timbers together on the                sling. Secure the sling in the hook by
      ground in line with the guys, with the         mousing.   Fasten the lower block to one
      butt ends pointing toward the back guy         of the legs near the butt so that it will
      and close to the point of erection.            be in a convenient position when the
                                                     shears have been raised but will be out
      Place a large block under the tops of          of the way during erection.
      the legs just below the point of lashing
      and insert a small spacer block                Rig another tackle in the back guy near
     between the tops at the same point (see         its anchorage if you use the shears on
     Figure 5-6). The separation between             heavy  lifts. Secure the two guys to the



5-8 Lifting and Moving Equipment
                                                                                FM 5-125




top of the shears with clove hitches to          Keep the legs from spreading by con-
legs opposite their anchorages above             necting them with rope, a chair, or
the lashing.                                     boards. It may be neceesary, under
                                                 some conditions, to anchor each leg of
Lift the top end of the shears legs and          the shears while erecting them to keep
"walk" them up by hand until the                 the legs from sliding in the wrong
tackle on the rear guy line can take             direction.
effect (see Figure 5-7, page 5-10). It
will take several people (depending on
the size of the shears) to do this. Then               OPERATING SHEARS
raise the shears legs into final position   The rear guy is a very important part of the
by hauling in on the tackle. Secure the     shears rigging, since it is under a consider-
front guy line to its anchorage before      able strain during hoisting. To avoid guy-
raising the shears legs, and keep a         line failure, design them according to the
slight tension on this line to control      principles discussed in Chapter 4, Section II.
movement.                                   The front guy has very little strain on it and


                                                    Lifting and Moving Equipment 5-9
FM 5-125



is used mainly to aid in adjusting the       loads, the fall line of the tackle of the shears
drift and to steady the top of the shears    can be led straight out of the upper block.
when hoisting or placing the load. You may   When handling heavy loads, you may have
have to rig a tackle in the rear guy for     to lash a snatch block near the base of one of
handling heavy loads. During opera-          the shear legs to act as a leading block (see
tion, set the desired drift by adjusting     Figure 5-8). Run the fall line through the
the rear guy, but do not do this while a     leading block to a hand- or power-operated
load is on-the shears. For handling light    winch for heavy loads.




5-10 Lifting and Moving Equipment
                                                                                  FM 5-125




                                     BOOM DERRICKS
A boom derrick is a lifting device that incor- swing more than 180 degrees when it is set
porates the advantages of a gin pole and the   on a turn plate or turn wheel.
long horizontal reach of a boom. Use the
boom derrick to lift and swing medium-size             RIGGING BOOM DERRICKS
loads in a 90-degree arc on either side of the
resting position of the boom, for a total      For hoisting medium loads, rig a boom to
                                               swing independently of the pole. Take
swing of 180 degrees. When employing a         care to ensure the safety of those using the
boom derrick in lifting heavy loads, set it on installation. Use a boom only temporarily
a turn plate or turn wheel to allow the mast   or when time does not permit a more sta-
and boom to swing as a unit. A mast is a       ble installation. When using a boom on a
gin pole used with a boom. The mast can        gin pole, more stress is placed on the rear



                                                      Lifting and Moving Equipment 5-11
FM 5-125



guy; therefore, you may need a stronger guy.
In case larger rope is not at hand, use a set
of tackle reeved with the same size rope as
that used in the hoisting tackle as a guy line
by extending the tackle from the top of the
gin pole to the anchorage. Lash the block
attached to the gin pole at the point where
the other guys are tied and in the same
manner. The procedure is as follows:
     Rig a gin pole as described on page 5-1,
     but lash another block about 2 feet
     below the tackle lashing at the top of
     the pole (see Figure 5-9). Reeve the
     tackle so that the fall line comes from
     the traveling block instead of the
     standing block. Attach the traveling
     block to the top end of the boom after
     erecting the gin pole.
     Erect the gin pole in the manner
     described on page 5-1, but pass the fall
     line of the tackle through the extra         Use manpower to lift the boom in place
     block at the top of the pole before erect-   on the mast through the sling that will
     ing it to increase the MA of the tackle      support it if the boom is light enough.
     system.                                      The sling consists of two turns of rope
                                                  with the ends tied together with a
     Select a boom with the same diameter         square knot. The sling should pass
     and not more than two-thirds as long         through the center four turns of the
     as the gin pole. Spike two boards to the     block lashing on the mast and should
     butt end of the boom and lash them           cradle the boom. On heavier booms,
     with rope, making a fork (see Figure         use the tackle system on the top of the
     5-9). Make the lashing with a mini-          mast to raise the butt of the boom to
     mum of sixteen turns and tie it off with     the desired position onto the mast.
     a square knot. Drive wedges under the
     lashing next to the cleats to help make      Lash the traveling block of the gin pole
     the fork more secure (see Figure 5-9).       tackle to the top end of the boom as
                                                  described on page 5-1, and lash the
     Spike cleats to the mast about 4 feet        standing block of the boom tackle at
     above the resting place of the boom and      the same point. Reeve the boom tackle
     place another block lashing just above       so that the fall line comes from the
     these cleats. This block lashing will        standing block and passes through the
     support the butt of the boom. If a sepa-     block at the base of the gin pole. The
     rate tackle system is rigged up to sup-      use of the leading block on this fall line
     port the butt of the boom, place an          is optional, but when handling heavy
     additional block lashing on the boom         loads, apply more power to a horizontal
     just below the larger lashing to secure      line leading from the block with less
     the running block of the tackle system.      strain on the boom and guys.


5-12 Lifting and Moving Equipment
                                                                                  FM 5-125



       ERECTING BOOM DERRICKS                  flatcars when the base of the gin pole cannot
                                               be set close to the object to be lifted. It is
Raise the boom into position when the rig-     used also on docks and piers for unloading
ging is finished. When working with heavy      boats and barges. Swing the boom by push-
loads, rest the base of the boom on the        ing directly on the load or by pulling the
ground at the base of the pole. Use a more     load with bridle lines or tag lines. Adjust
horizontal position when working with light    the angle of the boom to the mast by hauling
loads. In no case should the boom bear         on the fall line of the mast tackle. Raise or
against any part of the upper two-thirds of    lower the load by hauling on the fall line of
the mast.                                      the boom tackle. You should place a leading
                                               block (snatch block) at the base of the gin
      OPERATING BOOM DERRICKS                  pole. Lead the fall line of the boom tackle
                                               through this leading block to a hand- or
A boom on a gin pole provides a convenient     power-operated winch for the actual hoist-
means for loading and unloading trucks or      ing of the load.

                                   STIFF-LEG DERRICKS
The mast of a stiff-leg derrick is held in the mounted on the tower. The stiff-leg derrick
vertical position by two rigid, inclined struts also is used where guy lines cannot be pro-
connected to the top of the mast. The struts vided, as on the edge of a wharf or on a
are spread 60 to 90 degrees to provide sup- barge.
port in two directions and are attached to
sills extending from the bottom of the mast.                 STEEL DERRICKS
The mast is mounted on vertical pins. The
mast and boom can swing through an arc of Steel derricks of the stiff-leg type are avail-
about 270 degrees. The tackles for hoisting able to engineer troops in two sizes:
the load and raising the boom are similar to          A 4-ton rated capacity with a 28-foot
those used with the boom and gin pole (see            radius (see Figure 5-10, page 5-14).
page 5-11, Rigging Boom Derrick).
                                                      A 30-ton rated capacity with a 38-foot
     OPERATING STIFF-LEG DERRICKS                     radius,   when properly counter-
                                                      weighted.
A stiff-leg derrick equipped with a long boom
is suitable for yard use for unloading and Both derricks are erected on fixed bases.
transferring material whenever continuous The 4-ton derrick, including a skid-
operations are carried on within reach of its mounted, double-drum, gasoline-engine-
boom. When used on a bridge deck, move driven hoist, weighs 7 tons and occupies a
these derricks on rollers. They are sometimes space 20 feet square. The 30-ton derrick,
used in multistory buildings surmounted by including a skid-mounted, double-drum
towers to hoist material to the roof of the hoist, weighs about 22 tons and occupies a
main building to supply guy derricks space 29 feet square.
                           LIGHT HOISTING EQUIPMENT
Extended construction projects usually in- members by hand or by light hoisting equip-
volve erecting numerous light members as ment, allowing the heavy hoisting equip-
well as the heavy main members. Progress ment to move ahead with the erection of the
can be more rapid if you raise the light main members. Very light members can be


                                                      Lifting and Moving Equipment 5-13
FM 5-125




raised into place by two people using manila                POLE DERRICKS
handlines. When handlines are inadequate       The improved pole derrick, called a "dutch-
or when members must be raised above the       man", is essentially a gin pole constructed
working level, use light hoisting equipment.   with a sill and knee braces at the bottom
Many types of hoisting equipment for lifting   (see Figure 5-11, A). It is usually installed
light loads have been devised. Those dis-      with guys at the front and back. It is effec-
cussed here are only typical examples that     tive for lifting loads of 2 tons and, because
can be constructed easily in the field and     of its light weight and few guys, is readily
moved readily about the job.                   moved from place to place by a small squad.



5-14 Lifting and Moving Equipment
                        FM 5-125




Lifting and Moving Equipment 5-15
FM 5-125



               BRAVE DERRICKS                                JINNIWINK DERRICKS
 The braced derrick, known as a "monkey", is      This derrick is suitable for lifting loads
 very useful for filling in heavy members         weighing 5 tons (see Figure 5-11, C, page
 behind the regular erection equipment (see       5-15). Hand-powered jinniwinks are
 Figure 5-11, B, page 5-15). Two back guys        rigged preferably with manila rope. Those
 are usually employed when lifting heavy          operated by a power-driven hoist should
 loads, although light members may be lifted      be rigged with wire rope, The jinniwink
 without them. Power is furnished by a            is lashed down to the structural frame at
 hand- or power-driven hoist. The construc-       both the front sill and tail sill to prevent
 tion of the base of the monkey permits it to     the tail sill from rising when a load is
 be anchored to the structure by lashings to      lifted.
 resist the pull of the lead line on the snatch
 block at the foot of the mast.

                            Section II. Moving Equipment
Skids, rollers and jacks are used to move         (see Figure 5-12). A firm and level founda-
heavy loads. Cribbing or blocking is often        tion for cribbing is essential, and the bottom
necessary as a safety measure to keep an          timbers should rest firmly and evenly on
object in position or to prevent accidents to     the ground. Blocking used as a foundation
people who work under or near these heavy         for jacks should be sound and large enough
objects. Cribbing is formed by piling tim-        to carry the load. The timbers should be
bers in tiers, with the tiers alternating in      dry, free from grease, and placed firmly on
direction, to support a heavy weight at a         the ground so that the pressure is evenly
height greater than blocking would provide        distributed.

                                      SKIDS
Place timber skids longitudinally under Oak planks 2 inches thick and about 15 feet
heavy loads either to--                   long make satisfactory skids for most opera-
    Distribute the weight over a greater tions. Keep the angle of the skids low to pre-
    area.                                 vent the load from drifting or getting out of
                                          control. You can use grease on skids when
    Make a smooth surface for skidding only horizontal movement is involved; how-
    equipment.                            ever, in most circumstances, greasing is dan-
    Provide a runway surface when rollers gerous because it may cause the load to drift
    are used (see Figure 5-13).           sideways suddenly.

                                         ROLLERS
Use hardwood or pipe rollers over skids for       round and long enough to pass completely
moving very heavy loads into position.            under the load being moved. Support the
Place the skids under the rollers to provide a    load on longitudinal wooden members to
smooth, continuous surface for the rollers.       provide a smooth upper surface for the rollers
Make sure that the rollers are smooth and         to move on. The skids placed underneath




5-16 Lifting and Moving Equipment
                        FM 5-125




Lifting and Moving Equipment 5-17
FM 5-125



the rollers must form continuous support.
Ordinarily, place four to six rollers under the
load to be moved (see Figure 5-13, page 5-17).
Place several rollers in front of the load and
roll the load slowly forward onto the rollers.
As the load passes, rollers are left clear
behind the load and are picked up and placed
in front of the load so that there is a continu-
ous path of rollers. In making a turn with a
load on rollers, incline the front rollers
slightly in the direction of the turn and the
rear rollers in the opposite direction. This
inclination of the rollers may be made by
striking them sharply with a sledge. For
moving lighter loads, make up the rollers and
set on axles in side beams as a semiperma-
nent conveyor. Permanent metal roller con-
veyors are available (see Figure 5-14). They
are usually made in sections.


                                            JACKS
To place cribbing, skids, or rollers, you may           Lowering the load onto the cribbing.
have to lift and lower the load for a short
distance. Jacks are used for this purpose.         Repeat this process as many times as nec-
Jacks are used also for precision placement        essary to lift the load to the desired height.
of heavy loads, such as bridge spans. A            Jacks are available in capacities from 5 to
number of different styles of jacks are avail-     100 tons (see Figure 5-16). Small capacity
able, but only use heavy duty hydraulic or         jacks are operated through a rack bar or
screw-type jacks. The number of jacks used         screw, while those of large capacity are
will depend on the weight of the load and
the rated capacity of the jacks. Be certain        usually operated hydraulically.
that the jacks are provided with a solid foot-
ing, preferably wooden blocking. Cribbing                    RATCHET-LEVER JACKS
is frequently used in lifting loads by jacking
stages (see Figure 5-15). The procedure            The ratchet lever jack, available to engi-
requires--                                         neer troops as part of panel bridge equip-
                                                   ment, is a rack-bar jack that has a rated
     Blocking the jacks.                           capacity of 15 tons (see Figure 5-16, A). It
     Raising the object to the maximum             has a foot lift by which loads close to its
     height of the jacks to permit cribbing        base can be engaged. The foot capacity is 7
     to be put directly under the load.            1/2 tons.




5-18 Lifting and Moving Equipment
                                                                                   FM 5-125



                                               Their principal uses are for tightening lines
                                               or lashings and for spreading or bracing
                                               parts in bridge construction.

                                                              SCREW JACKS
                                               Screw jacks have a rated capacity of 12 tons
                                               (see Figure 5-16, C). They are about 13 inches
                                               high when closed and have a safe rise of at
                                               least 7 inches. These jacks are issued with
                                               the pioneer set and can be used for general
                                               purposes, including steel erection.

                                                            HYDRAULIC JACKS
                                               Hydraulic jacks are available in Class IV
                                               supplies in capacities up to 100 tons (see
                                               Figure 5-16, D) Loads normally encountered
          STEAMBOAT RATCHETS                   by engineer troops    do not require large
                                               capacity hydralic . jacks. Those supplied
Steamboat ratchets (sometimes called push-
ing-and-pulling jacks) are ratchet screw       with the squad pioneer set are 11 inches
jacks of 10-ton rated capacity with end fit-   high and have a rated capacity of 12 tons
tings that permit pulling parts together or    and a rise of at least 5 1/4 inches. They are
pushing them apart (see Figure 5-16, B).       large enough for usual construction needs.




                                                      Lifting and Moving Equipment 5-19
                                                                                   FM 5-125




                                     CHAPTER          6


                                   Scaffolds


Construction jobs may require several           the hole is more than 1 inch or if the split
kinds of scaffolds to permit easy working       extends more than 3 inches in from the
procedures. Scaffolds may range from indi-      end. Use 3-inch planks to build the tem-
vidual planks placed on structural members      porary floor used for constructing steel
of the building to involved patent scaffold-    buildings because of the possibility that a
ing. Scaffold planks are placed as a decking    heavy steel member might be rested tem-
over--                                          porarily on the planks. Lay single scaffold
                                                planks across beams of upper floors or
    Swinging scaffolds.                         roofs to form working areas or runways (see
                                                Figure 6-1, page 6-2). Run each plank from
    Suspended scaffolds.                        beam to beam, with not more than a few
    Needle-beam scaffolds.                      inches of any plank projecting beyond the
                                                end of the supporting beam. Overhangs
    Double-pole, built-up, independent          are dangerous because people may step on
    scaffolds.                                  them and overbalance the scaffold plank.
                                                When laying planking continuously, as in
Scaffold planks are of various sizes, includ-   a runway, lay the planks so that their ends
ing 2 inches by 9 inches by 13 feet, 2 inches   overlap. You can stagger single plank runs
by 10 inches by 16 feet, and 2 inches by 12     so that each plank is offset with reference
inches by 16 feet. You may need 3-inch-         to the next plank in the run. It is advisable
thick scaffold planks for platforms that        to use two layers of planking on large
must hold heavy loads or withstand move-        working areas to increase the freedom of
ments. Planks with holes or splits are not      movement.
suitable for scaffolding if the diameter of

                                SWINGING SCAFFOLDS
The swinging, single plank, or platform       SINGLE-PLANK SWINGING SCAFFOLDS
type of scaffold must always be secured to   A single scaffold plank maybe swung over
the building or structure to prevent it from the edge of a building with two ropes by
moving away and causing someone to fall.     using a scaffold hitch at each end (see Fig-
When swinging scaffolds are suspended        ures 6-2, page 6-2, and 2-28, page 2-20). A
adjacent to each other, planks should never  tackle may be inserted in place of ropes for
be placed so as to form a bridge between     lowering and hoisting. This type of swing-
them.                                        ing scaffold is suitable for one person.



                                                                             Scaffolds 6-1
FM 5-125




6-2 Scaffolds
                                                                                    FM 5-125



   SWINGING PLATFORM SCAFFOLDS                    which the lower block of a set of manila
                                                  rope falls is attached. The scaffold is sup-
The swinging platform scaffold consists of a      ported by hooks or anchors on the roof of a
frame similar in appearance to a ladder with      structure. The fall line of the tackle must
a decking of wood slats (see Figure 6-3). It is   be secured to a member of the scaffold when
supported near each end by a steel stirrup to     in final position to prevent it from falling.

                                 SUSPENDED SCAFFOLDS
Suspended scaffolds are heavier than swing- be made up in almost any width up to
ing scaffolds and are usually supported on about 6 feet and may be 12 feet long,
outriggers at the roof. From each outrigger, depending on the size of the putlogs, or lon-
cables lead to hand winches on the scaffold.  gitudinal supports, under the scaffold. A
This type of scaffold is raised or lowered by light roof may be included on this type of
operating the hand winches, which must        scaffold to protect people from falling
contain a locking device. The scaffold may debris.




                                                                              Scaffolds 6-3
FM 5-125


                                NEEDLE-BEAM SCAFFOLDS
 This type of scaffold is used only for tempo- Figure 6-4). A scaffold hitch is used in the
 rary jobs. No material should be stored on rope supporting the needle beams to pre-
 this scaffold. In needle-beam scaffolding, vent them from rolling or turning over (see
 two 4- by 6-inch, or similar size, timbers are Figure 2-28, page 2-20). The hanging lines
 suspended by ropes. A decking of 2-inch are usually of 1 1/4-inch manila rope. The
 scaffold plank is placed across the needle rope is hitched to the needle beam, carried
 beams, which should be placed about 10 feet up over a structural beam or other support,
 apart. Needle-beam scaffolding is often and then down again under the needle
 used by riveting gangs working on steel beam so the latter has a complete loop of
 structures because of the necessity for fre- rope under it. The rope is then passed over
 quent changes of location and because of the support again and fastened around
 its adaptability to different situations (see itself by two half hitches.




                        DOUBLE-POLE BUILT-UP SCAFFOLDS
The double-pole built-up scaffold (steel or     by placing the two uprights on the ground
wood), sometimes called the independent         and inserting the diagonal members. The
scaffold, is completely independent of the      diagonal members have end fittings that
main structure. Several types of patent         permit rapid locking-in position. The first
independent scaffolding are available for       tier is set on steel bases on the ground. A
simple and rapid erection (see Figure 6-5).     second tier is placed in the same manner on
The scaffolding can be built from wood, if      the first tier, with the bottom of each
necessary. The scaffold uprights are braced     upright locked to the top of the lower tier. A
with diagonal members, and the working          third and fourth upright can be placed on
level is covered with a platform of planks.     the ground level and locked to the first set
All bracing must form triangles. The base of    with diagonal bracing. The scaffolding can
each column requires adequate footing           be built as high as desired, but high scaf-
plates for the bearing area on the ground.      folding should be tied in to the main struc-
Patented steel scaffolding is usually erected   ture.


6-4 Scaffolds
    FM 5-125




Scaffolds 6-5
FM 5-125



                                   BOATSWAIN'S CHAIRS
Boatswain's chairs can be made several notched board inserted through the two leg
ways, but they usually consist of a sling for loops will provide a comfortable seat (see
supporting one person.                         Figure 6-7). The loop formed as the running
                                               end to make the double bowline will still
                 ROPE CHAIR                    provide a back support, and the rolling hitch
                                               can still be used to lower the boatswain's
You can make a rope boatswain's chair by chair.
using a double bowline and a rolling hitch
(see Figure 6-6). One person can operate the           ROPE CHAIR WITH TACKLE
rope seat to lower himself by releasing the
grip of the rolling hitch. A slight twist with The boatswain's chair is supported by a four
the hand on the hitch permits the suspen- part rope tackle (two double blocks [see Fig-
sion line to slip through it, but when the ure 6-8]). One person can raise or lower
hand pressure on the hitch is released, the himself or can be assisted by a person on the
hitch will hold firmly.                        ground. When working alone, the fall line is
                                               attached to the lines between the seat and
          ROPE CHAIR WITH SEAT                 the traveling block with a rolling hitch. As a
If the rope boatswain's chair must be used to safety precaution, a figure-eight knot should
support a person at work for some time, the be tied after the rolling hitch to prevent acci-
rope may cause considerable discomfort. A dental untying.




6-6 Scaffolds
    FM 5-125




Scaffolds 6-7
                                                     FM 5-125




            APPENDIX


Figures   and   Tables        of    Useful
          Information




                 Figures and Tables of Useful Information A-1
FM 5-125




A-2 Figures and Tables of Useful Information
                                    FM 5-125




Figures and Tables of Useful Information A-3
FM 5-125




A-4 Figures and Tables of Useful Information
                                    FM 5-125




Figures and Tables of Useful Information A-5
FM 5-125




A-6 Figures and Tables of Useful Information
                                                                  FM 5-125



                             G l o s s a r y


AR        Army regulation

ATTN      attention


BA        bearing area

bend      A bend (in this manual called a knot) is used to fasten two ropes
          together or to fasten a rope to a ring or loop.

bight     A bight is a bend or U-shaped curve in a rope.

BS        breaking strength; the greatest strength.


CH        clay, high compressibility

CL        clay, low compressibility

cordage   Ropes and twines made by twisting together vegetable or synthetic
          fibers.


D         diameter

D         drift distance

DA        Department of the Army


EL        effective length

ENG       engineer


FM        field manual

FS        factor of safety

                                                                 Glossary-1
FM 5-125



 GC          clayey gravel

 GP          poorly graded gravel

 GW          well-graded gravel


 HD          horizontal distance

 HP          holding power

 HQ          headquarters


 IPS         improved plow steel


 L           length of the sling

 line        A line (sometimes called a rope) is a thread, string, cord, or rope, espe-
             cially a comparatively slender and strong cord. This manual will use
             the word rope rather than line in describing knots, hitches, rigging,
             and the like.

 loop        A loop is formed by crossing the running end cover or under the stand-
             ing part, forming a ring or circle in the rope.

 L/d         length-to-diameter ratio

 L/t         length-to-thickness ratio


 MA          mechanical advantage

 MD          mean depth

 MH          silt, high compressibility

 ML          silt, low compressibility

 MPS         mild plow steel


Glossary-2
                                                                                FM 5-125



N                 number of slings

No                number


OH                organic soil, high compressibility

OL                organic soil, low compressibility

overhand turn or loop An overhand turn or loop is made when the running end passes
                  over the standing part.


PS                plow steel

psi               pound(s) per square inch


rope              A rope (often called a line) is a large, stout cord made of strands of
                  fiber or wire that are twisted or braided together.

round turn        A round turn is a modified turn, but with the running end leaving the
                  circle in the same general direction as the standing part.

running end       The running end is the free or working end of a rope.


SC                clayey sandy soil

SF                finely graded sand

SP                poorly graded sand

SR                slope ratio

standing part     The standing part is the rest of the rope, excluding the running end.

SW                well-graded sand

SWC               safe working capacity



                                                                              Glossary-3
FM 5-125



 T                tension

 TB               technical bulletin

 TC               training circular

 TL               timber length

 TM               training manual

 TRADOC           United States Army Training and Doctrine Command

 turn            A turn is the placing of a loop around a specific object (such as a post,
                 rail, or ring) with the running end continuing in a direction opposite to
                 the standing part.


 underhand turn or loop An underhand turn or loop is made when the running end
                 passes under the standing part.

 US              United States (of America)


 V               vertical distance

 VD              vertical distance


 W               weight of the load to be lifted

 W3              width of spar(s)

 WL              width of the load

 WST             width of the sloping trench


 Y               Perpendicular distance from the rear guy line to the base of the gin
                 pole or, for shears, to a point on the ground midway between the
                 shears legs.



Glossary-4
                                                                              FM 5-125



                                 R e f e r e n c e s

SOURCES USED
These are the sources quoted or paraphrased in this publication.

Army Publications

Army Regulations (ARs)
AR 59-3. Air Transportation Movement of Cargo by Scheduled Military and Commercial Air
  Transportation -- CONUS Outbound. 1 February 1981.

Field Manuals (FMs)
FM 5-34. Engineer Field Data. 14 September 1987.
FM 5-434. Earthmoving Operations. 30 September 1992,
FM 10-500-7. Airdrop Derigging and Recovery Procedures. 20 September 1994.
FM 20-22. Vehicle Recovery Operations (FMFRP 4-19). 18 September 1990.
FM 55-9. Unit Air Movement Planning. 5 April 1993.
FM 55-12. Movement of Units in Air Force Aircraft (AFM 76-7; FMFM 4-6; OPNAVINST
  4630.27A). 10 November 1989,
FM 55-15. Transportation Reference Data. 9 June 1986.

Supply Catalog (SC)
SC 5180-90-CL-N17. Tool Kit Rigging, Wire Rope: Cutting, Clamping, and Splicing
  w/Chest. 23 October 1981.

Technical Bulletins (TBs)
TB 43-0142. Safety Inspection and Testing of Lifting Devices. 30 August 1993.
TB ENG 317. Air Movement Instructions: Grouping, Modification, Disassembly and
  Reassembly for Crane, Shovel, Truck Mounted, 20 Ton, 3/4 Cubic Yard, Gasoline
  Driven, Garwood Model M-20-B. 28 June 1962.
TB ENG 324. Air Movement Instructions (Grouping, Modification, Disassembly, and
  Reassembly) for Mixer, Concrete, GED, Trailer Mounted (Construction Machinery
  Model 16S). 2 July 1962.
TB ENG 326. Air Movement Instructions: (Grouping, Modification, Disassembly, and
  Reassembly) for Scraper, Earth Moving, Towed, 12 Cubic Yard, Cable Operated,
  Letorneau-Westinghouse Model LPO. 9 July 1962.


                                                                         References-1
FM 5-125



TB ENG 330. Air Movement Instructions (Grouping, Modification, Disassembly, and
  Reassembly) for Truck, Stake: 5-Ton, 6x6; Military Bridging on ORD M-139 Chassis.
  3 July 1962,

Training Circular (TC)
TC 90-6-1, Military Mountaineering. 26 April 1989.

Technical Manuals (TMs)
TM 5-270, Cableways, Tramways, and Suspension Bridges. 21 May 1964.
TM 10-500-70. Airdrop of Supplies and Equipment: Rigging Dry Bulk Materials and
  Potable Water for Free Drop. 2 November 1967.



DOCUMENTS NEEDED

These documents must be available to the intended users of this publication.

Department of the Army (DA) Forms
DA Form 2028. Recommended Changes to Publications and Blank Forms. 1 February 1974.




References-2
        FM 5-125




Index




        Index-1
FM 5-125




Index-2
FM 5-125




Index-3
FM 5-125




Index-4
                                                                                       FM 5-125
                                                                                 3 OCTOBER 1995




By Order of the Secretary of the Army:


                                                    DENNIS J. REIMER
                                                 General, United States Army
Official:                                                Chief of Staff
     JOEL B. HUDSON
Acting Administrative Assistant to the
       Secretary of the Army
                          00725




DISTRIBUTION:

Active Army, USAR, and ARNG: To be distributed in accordance with DA
Form 12-11 E, requirements for FM 5-125, Rigging Techniques, Procedures, and
Applications (Qty rqr block no. 5426)




                                             C U.S. GOVERNMENT PRINTING OFFICE: 1995 - 628 - 027 / 40064


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