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continued from previous page                         Versatile termination method for long cables
                                                              Pat. 9,791,337 U.S. class D07B 1/185 Int. class H01R 43/00
                                                              Inventor: Richard V. Campbell, Havana, FL., Phillip Bull,
                                                              Havana, FL.
                                                              Assignee: Bright Technologies, LLC., Havana, FL.
                                                               A method for creating a composite cable having at least
                                                              one advanced termination on at least one end. An advanced
                                                              termination is added to an end of a short synthetic ten-
                                                              sile strength member. The strength of the tensile strength
                                                              member and termination is then tested. Once tested satis-
                                                              factorily, the short cable is spiced onto a long cable of the
         Figure 20: Third exemplary loss of metallic cross-sectional  area
         (“LMA”) traces.                                      same type using prior art splicing techniques. The union
                                                              of the short cable and the long cable creates a “composite”
         theless, test wires could be temporarily attached and used   cable having a advanced termination on at least one end.
         to more accurately calibrate the readings from an incremen-  In  most  applications  it  is  preferable  to  set  the  length  of
         tal distance counter wheel. They could be removed after the   the short cable so that the interwoven splice will exist at a
         calibration. This method may be adequate.            desired location.
           Alternatively, instead of using test wires, plastic magnetic   Figure 21 shows two components of a composite cable be-
         distance markers  14—for example  made from UHMWPE   fore they are joined together. Short cable 26 includes a ad-
         and filled with iron filings—could be molded onto the wire   vanced termination, that has been attached to one end as de-
         rope 12. Furthermore, wear resistant paints could be filled   scribed previously. Cable 10 in this example is a “long cable”
         with iron filings and applied to the rope as markers.
           As another option, for plastic filled wire ropes, short sec-  with no attached hardware. In this example both cables are
         tions  of  the  intermediate  plastic  layer  can  be  filled  with   made of braided strands. The drawing does not depict the
         iron  filings  in  order  to  establish  certain  distance  markers
         14 at desired distances along the length of the rope. Such
         distance markers 14, as described above, could be magneti-
         cally detected with present NDE equipment (for  example,
         equipment used in LMA rope inspection as disclosed in U.S.
         Pat. No. 4,659,991 or U.S. Pat. No. 8,386,395) and used for
         absolute  distance  measurements.  In  other  words,  present
         wire rope equipment with LMA capabilities could be used
         as magnetic sensor heads 30. LF-type signals from wire rope
         test equipment also could be used, but would be more dif-
         ficult  to  interpret.  Under  certain  conditions,  the  distance
         markers 14 simultaneously could be used for relative in-situ
         calibration of the LMA signal during magnetic inspections
         of the rope.
           For densely-packed compacted  multistrand ropes, space   Figure 21: Perspective view, showing a terminated short cable.
         between wires and strands is kept to a minimum. Hence, at-
         taching or embedding magnetic or visual markers to or into   braided construction completely accurately, since it is quite
         the rope may not be feasible. In this case, wear patterns as   complex, but the lines show that some of the braid compo-
         detected and recorded by wire rope NDE along the rope can   nents are twisted in one direction and some are twisted in
         be used as distance markers as follows.              the opposite direction.
           Over its lifetime, but long before retirement, a wire rope   It is possible using prior art techniques to create an in-
         12 will  develop distinctive wear patterns along its length   terwoven, interlocking, or otherwise gripping splice between
         that can be detected and recorded by a magnetic NDE sys-  these two pieces of cable. Figure 22 shows the two cable seg-
         tem. Furthermore, as will be discussed in the following, dis-  ments joined together by an interwoven splice. Short cable
         tance measurements can be combined with wire rope NDE.
                                                              26 and long cable 10 are joined together by interwoven sec-
                                                              tion 24. The result is a much longer “composite” cable.
                                                               The terms “short” and “long” are relative to each other.
                                                              A typical “short” cable might range from as short as 5 me-
                                                              ters to as long as 100 meters. In some rare cases this may
                                                              be even longer. A “long” cable might range from 50 me-
                                                              ters up to several km in length. When the terms “short”
                                                              and “long” are used in this description, the reader should
                                                              understand that the “long” cable is typically 4 or more
                                                              times  longer  than  the  short  cable.  The  determination
                                                              of the length of each component is often dictated by the
                                                              availability of testing equipment for evaluating the per-
                                                              formance of the short cable, and the actual application, as
                                                              will be explained subsequently.
                                                               A detailed explanation of the prior art interweaving tech-
                                                              niques used in cable splices is beyond the scope of this dis-
                                                              closure, but the reader may benefit from some general expla-
         66     Wire Rope News & Sling Technology   April 2018
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