Click Here to
Order this information in Print

Click Here to
Order this information on CD-ROM

Click Here to
Download this information in PDF Format


Click here to make your Home Page

Page Title: Construction of Wire Rope
Back | Up | Next

Click here for a printable version




Information Categories
.... Administration
Food and Cooking
Nuclear Fundamentals
  Educational CD-ROM's
Printed Manuals
Downloadable Books



in length, depending on the size fitting used. The rule of thumb for preferred length of the eye is 5 times the diameter of the fitting. This prevent uneven loading of the eye. The following is the procedure for splicing four-strand  rope: 1. Measure a distance of seven times the rope circumference from the end of the rope and mark using a temporary whipping. Determine the eye size and form a loop which places the first whipping on the standing part at the end of the eye and mark with a second temporary   whipping. 2.  Unlay  the  strands  of  the  rope  to  the  first whipping and cut out the center core. Looking in the direction of the standing part, tuck the first strand under the top strand of the standing part from left to right with the lay at the base of the second whipping. 3.   Tuck the second strand under the next strand of the standing part with the lay. Tuck the third strand under the next strand of the standing part with the lay. 4. Turn the rope over and tuck the fourth strand under the last strand of the standing part of the lay. 5.  This  constitutes  one  full  tuck.  Ensure  all working strands are pulled tight and free of twists. 6. Continue tucking all four strands in succession over and under the strands of the standing part for a total of six tucks. 7. Using a light strain, set the splice. 8. Marry the working strands using an inside whipping under the strands of the standing part at the last full tuck. 9.   Cut the remaining working strands off flush with the rope. NOTE The  last  two  tucks  may  be  tapered,  if desired, by cutting approximately half of the fibers for each taper. Chafing gear on the eye is required  for  abrasion. WIRE  ROPE LEARNING   OBJECTIVE:   Describe   the construction, use, and care of wire rope. Although   wire   rope   may   have   only   a   few applications in some Navy ships, in others, wire rope is very important. It behooves all seamen to learn all they can about wire rope. CONSTRUCTION  OF  WIRE  ROPE The basic unit of wire-rope construction is the individual wire made of steel or other metal in various sizes. These wires are laid together to form strands. The number of wires in a strand varies according to the purpose for which the rope is intended. A number of strands are laid together to form the wire rope itself. Wire rope is designated by the number of strands per rope and the number of wires per strand. Thus, a 6 X 19 rope has 6 strands with 19 wires per strand, but has the same outside diameter as a 6 X 37 wire rope, which has 6 strands with 37 wires of much smaller size per strand. Wire rope made up of a large number of small wires is flexible, but the small wires break so easily that the wire rope is not resistant to external abrasion. Wire rope made up of a smaller number of larger wires is more resistant  to  external  abrasion,  but  is  less  flexible. The strands of the wire rope are laid up around a central core, which may be fiber, a single strand of wire, or an independent wire rope. A fiber core contributes flexibility,  cushions  the  strands  as  the  wire  rope contracts under strain, and holds a portion of lubricant for  continuous  lubrication.  A  wire  core  is  stronger  than a fiber core and can be used where conditions such as high temperatures would damage the fiber. Some end views of the arrangements of strands in wire ropes are shown in figure 3-25. Wire rope may be fabricated by either of two methods. If the strands of wires are shaped to conform to the curvature of the finished rope before their laying up, the wire rope is termed preformed. If the strands are not shaped before fabrication, the wire rope is termed non-preformed. When cut, preformed wire rope tends not to untwist and is more flexible than other wire rope. Wire rope is made of annealed steel, traction steel, or improved plow steel. The basic metal may be plain or galvanized. Galvanizing protects the rope from the elements, but makes it stiffer and reduces its strength by as   much   as   10   percent.   Galvanized   rope   most commonly is used for standing rigging, but also is used for some running rigging (such as wheel ropes) where it is not subject to much wear. Ordinarily, this rope is not used for hoisting jobs because the constant bending and flexing as the rope runs over the sheaves and around drums causes the protective coating to crack and peel off. 3-18

Privacy Statement - Press Release - Copyright Information. - Contact Us - Support Integrated Publishing

Integrated Publishing, Inc. - A (SDVOSB) Service Disabled Veteran Owned Small Business