Abstract:
An apparatus includes a backshell, the backshell having a shell defining an interior space, the interior space configured to encase a portion of a plurality of core cables between an entry component and a connector body in a steel wire armored (SWA) cable, wherein the portion represents an excess amount of the core cables when the SWA cable is uncoiled.

Description:
TECHNICAL FIELD 
       [0001]    This disclosure relates generally to connectors. More specifically, this disclosure relates to a custom backshell for a connector used for steel wire armored (SWA) cables. 
       BACKGROUND 
       [0002]    SWA cables are not very flexible. Bending or coiling the non-flexible cable can cause the connector pins to pull out of the pin holder or the wire crimps to let go thereby losing physical contact with the mating connector or receptacle in the remote terminal unit (RTU) enclosure, which leads to production outages caused by well site shutdown. 
       SUMMARY 
       [0003]    This disclosure provides a custom backshell for a connector used for steel wire armored (SWA) cables. 
         [0004]    In a first embodiment, a backshell includes a shell defining an interior space. The interior space is configured to encase a portion of a plurality of core cables between an entry component and a connector body in a SWA cable, wherein the portion represents an excess amount of the core cables when the SWA cable is uncoiled. 
         [0005]    In a second embodiment, a SWA cable includes a plurality of core cables and a backshell. The plurality of core cables is configured to transmit a signal. The backshell includes a shell defining an interior space, the interior space configured to encase a portion of a plurality of core cables between an entry component and a connector body in a steel wire armored (SWA) cable, wherein the portion represents an excess amount of the core cables when the SWA cable is uncoiled. 
         [0006]    In a third embodiment, a method includes coiling a SWA cable having a plurality of core cables. The coiling of the SWA cable causes a reduction in an excess amount of the plurality of core cables disposed in an interior space of a backshell coupled to the SWA cable. The method also includes uncoiling the SWA cable. The uncoiling of the SWA cable causes the excess amount of the core cables to increase in the interior space of the backshell. 
         [0007]    Other technical features may be readily apparent to one skilled in the art from the following figures, descriptions, and claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    For a more complete understanding of this disclosure, reference is now made to the following description, taken in conjunction with the accompanying drawings, in which: 
           [0009]      FIG. 1  illustrates an example steel wire armored (SWA) cable according to this disclosure; 
           [0010]      FIG. 2  illustrates an end of the SWA cable according to this disclosure; 
           [0011]      FIG. 3  illustrates an example cross section of a backshell according to this disclosure; and 
           [0012]      FIG. 4  illustrates an example method for accommodating an excess amount of a plurality of core cables in a backshell according to this disclosure. 
       
    
    
     DETAILED DESCRIPTION 
       [0013]      FIGS. 1 through 4 , discussed below, and the various embodiments used to describe the principles of the present disclosure in this patent document are by way of illustration only and should not be construed in any way to limit the scope of the disclosure. Those skilled in the art will understand that the principles of the present disclosure may be implemented in any type of suitably arranged device or system. 
         [0014]    A steel wire armored (SWA) multi-core cable often includes a quick/multi pin connector. SWA cables are generally not very flexible and, for that reason, are meant to be laid and completed situ (on-site). In many cases, the SWA cables are manufactured and tested in a workshop before being shipped to a third party supplier for integration. More testing is performed at the client warehouse prior to final installation at site. This means the non-flexible cable is handled as a flexible cable as it is repeatedly coiled and uncoiled and handled at numerous stages in the supply chain. The movement of the outer and inner layer of the SWA cable is inevitable when the cable is subjected to being handled, coiled and uncoiled. It is normal to experience movement between the inner core cable and outer armoring with SWA cables. The outer layer has a different bending radius and amount of compression compared to the inner layer of the cable. This difference allows the inner layer to creep within the outer layer when the cable is bent and coiled. Inner retraction of the inner layer can be as much as fifty millimeters after the first cut of the cable and further retraction of up to six millimeters after coiling a cable fifteen meters long. The inner layer retraction exerts stress on the quick connector pins and crimps as quick connectors allow very limited tolerance for any internal movement once assembled. The above described problem may cause either the connector pins to pull out of the pin holder or the wire crimps to let go of the core cables, thereby losing physical contact with the mating connector or receptacle in the RTU enclosure, which leads to production outages caused by well site shutdown. 
         [0015]      FIG. 1  illustrates an example steel wire armored (SWA) cable  100  according to this disclosure.  FIG. 2  illustrates an end  200  of the SWA cable  100  according to this disclosure. The embodiment of the SWA cable  100  illustrated in  FIG. 1  and the end  200  of the SWA cable  100  illustrated in  FIG. 2  are for illustration only.  FIGS. 1 and 2  do not limit the scope of this disclosure to any particular implementation. 
         [0016]    The SWA cable  100  includes an outer jacket  105 , steel armored wires  110 , an inner jacket  115 , a plurality of core cables  120 , a cable gland assembly  125 , a backshell  130 , and a connection cap  135 . The outer jacket  105  provides an outer cover for the SWA cable  100 . The steel armored wires  110  provide strength to the SWA cable  100  and add further protection to the plurality of core cables  120 . The inner jacket  115  provides a barrier between the steel armored wires  110  and the core cables  120 . The core cables  120  are used to transmit a plurality of signals along the SWA cable  100 . The cable gland assembly  125  is located at each end of the SWA cable  100 . The cable gland assembly  125  connects and secures the inner jacket  115 , the steel armor wires  110  and the outer jacket  105 . 
         [0017]    An excess amount  205  of the core cables  120  extends beyond the cable gland assembly  125  to connect to a connection cap  135  at both ends of the SWA cable  100 . The connection cap  135  includes a plurality of pins  210  used to connect the core cables  120  to corresponding pins located in a terminal (not shown). In some embodiments, the connection cap  135  may be (or include) a MS5015 connector by AMPHENOL AEROSPACE. A backshell  130  is provided between the cable gland assembly  125  and the connection cap  135  to encompass and accommodate the excess amount  205  of the core cables  120 . The excess amount  205  of the core cables  120  is provided for contraction of the core cables  120  into the SWA cable  100  when the SWA cable  100  is coiled for transport or storage. For example, a fifteen meter long SWA cable  100  can experience fifty millimeters of retraction after cutting the core cables to a suitable length and five millimeters of retraction after coiling. Because of this reduction in length after cutting, the excess amount  205  of the core cables  120  is determined based on the suitable length of the SWA cable  100 . The core cables  120  experience a reduction of length after cutting to a suitable size based on the overall length. 
         [0018]    The excess amount  205  is also determined based on coiling and uncoiling the SWA cable  100 . The core cables  120  have a different bending radius than the SWA cable  100  and the steel armor wires  110  when the SWA cable  100  is coiled. That is, when the SWA cable  100  is coiled, the core cables  120  experience a different bending that causes a portion of the excess amount  205  to retract into the SWA cable  100 . When the SWA cable  100  is uncoiled, the excess amount  205  extends out from the end of the SWA cable  100 . The fluctuation of the length of the excess amount  205  causes stress on the connections with the pins  210  of the connection cap  135 . The stress could cause damage to each connection, reducing the connection or totally uncoupling the core cable from the pin  210 . In order to accommodate the fluctuations in excess amount  205  of the core cables  120 , a backshell  130  is provided. The backshell is described in detail in regards to  FIG. 3 . 
         [0019]    Although  FIGS. 1 and 2  illustrate an example of a SWA cable  100 , various changes may be made to  FIGS. 1 and 2 . For example, while twenty core cables are illustrated in  FIG. 1 , other embodiments can include more or less than twenty core cables. 
         [0020]      FIG. 3  illustrates an example cross section  300  of a backshell  130  according to this disclosure. The embodiment of the backshell  130  illustrated in  FIG. 3  is for illustration only.  FIG. 3  do not limit the scope of this disclosure to any particular implementation. 
         [0021]    The backshell  130  is used to accommodate an excess amount  205  of the core cables  120 . As shown in  FIG. 3 , the backshell  130  includes a shell that defines an interior space  315 . The length  305  of the backshell  130  is less than the maximum excess amount  205  of the core cables  120 . The length  305  and diameter  310  of the backshell  130  are selected to have an interior space  315  accommodate the excess amount  205  of the core cables  120 . For example, for a SWA cable  100  that uses an AMPHENOL connection cap  135 , the length  305  of the backshell could be 113 mm and the diameter  310  could be 57 mm. While maintaining the interior space  315  required for the excess amount  205  of the core cables  120 , increasing the inner diameter  310  would require less length  305  for the back shell and the opposite is also true with decreasing the inner diameter  310  and extending the length  305 . The backshell  130  provides extra interior space  315  for the core cables  120  to contract or expand without stressing the connections with the pins  210  of the connection cap  135 . The edges  320  are rounded to protect the core cables from damage or fraying. The edges  320  could have any treatment provided to reduce the amount of damage from friction or rubbing of the core cables  120  on the edges  320 . 
         [0022]    Although  FIG. 3  illustrates one example of a backshell  130  in a SWA cable  100 , various changes may be made to  FIG. 3 . For example, the relative sizes and shapes of the components of the backshell  130  are merely one example; these components could be changed to suit particular needs. 
         [0023]      FIG. 4  illustrates an example method  400  for accommodating an excess amount  205  of a plurality of core cables  120  in a backshell  130  according to this disclosure. For example, the process depicted in  FIG. 4  may be performed in conjunction with an SWA cable  100  in  FIG. 1 . 
         [0024]    In operation  405 , the SWA cable  100  is coiled causing a reduction in the excess amount  205  of the core cables  120  in a backshell  130 . The difference in the bending radius between the steel armor wires  110  and the core cables  120  cause the core cables  120  to bend more than the steel armor wires  110 . This difference in bending radius causes a reduction in the excess amount  205  of the core cables  120  encased in the backshell  130 . The excess amount  205  is determined based on the reduction in length based on the maximum amount of bending while the SWA cable  100  is coiled. 
         [0025]    In operation  410 , the SWA cable  100  is uncoiled causing the excess amount  205  of the core cables  120  to expand in the backshell  130 . Because the bending radii are different, when the SWA cable  100  is uncoiled, the excess amount  205  returns to the position when the SWA cable  100  is straight or an increase in the excess amount  205  of the core cables  120  from the coiled state. The interior space  315  of the backshell  130  provides an area for the excess amount  205  of core cables  120  to remain while the SWA cable  100  is straight or uncoiled. 
         [0026]    Although  FIG. 4  illustrates one example of a method  400  for accommodating an excess amount  205  of a plurality of core cables  120  in a backshell  130 , various changes may be made to  FIG. 4 . For example, various steps shown in  FIG. 4  could overlap, occur in parallel, occur in a different order, or occur any number of times. 
         [0027]    It may be advantageous to set forth definitions of certain words and phrases used throughout this patent document. The terms “transmit,” “receive,” and “communicate,” as well as derivatives thereof, encompasses both direct and indirect communication. The terms “include” and “comprise,” as well as derivatives thereof, mean inclusion without limitation. The term “or” is inclusive, meaning and/or. The phrase “associated with,” as well as derivatives thereof, may mean to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, have a relationship to or with, or the like. The phrase “at least one of,” when used with a list of items, means that different combinations of one or more of the listed items may be used, and only one item in the list may be needed. For example, “at least one of: A, B, and C” includes any of the following combinations: A, B, C, A and B, A and C, B and C, and A and B and C. 
         [0028]    While this disclosure has described certain embodiments and generally associated methods, alterations and permutations of these embodiments and methods will be apparent to those skilled in the art. Accordingly, the above description of example embodiments does not define or constrain this disclosure. Other changes, substitutions, and alterations are also possible without departing from the spirit and scope of this disclosure, as defined by the following claims.