Abstract:
A wire-line section and connection system for carrying electrical power to a down-hole tool in a well is provided. Each section includes a tubular sheath forming a passageway that encloses a conductor having a first connector at one end and a complementary second connector at the other that enables wire-line sections to be coupled together. A number of wire-line sections can be connected together to form a wire-line connection system that connects to a device connector attached to the down-hole tool. The upper end of the system includes an entry sub-assembly to connect to a source of electric power for the down-hole tool.

Description:
PRIORITY CLAIM 
       [0001]    This application claims the priority of Canadian Patent Application no. 2,572,755 for “Wire-Line Connection System” filed on Jan. 3, 2007, and further claims the priority of Canadian Patent Application no. 2,604,816 for “Wire-Line Connection System” filed on Sep. 28, 2007. The entireties of both priority applications are hereby incorporated by reference. 
       FIELD OF THE INVENTION 
       [0002]    The present invention is related to the field of wire-line connection systems used to provide electrical power to down-hole tools in wells. 
       BACKGROUND 
       [0003]    It is known in the art to use a wire-line connection system, comprising a series of modular component sections, to convey electric current to or from down-hole devices, such as, but not limited to, survey, navigation, exploration, sensor and drilling devices but many of these systems are complex and expensive to implement. 
         [0004]    It is, therefore, desirable to provide a wire-line connection system that can form a releasable, fluid-tight and interlocking connection between wire-line sections that are simple and inexpensive to manufacture. 
       SUMMARY 
       [0005]    A wire-line section for transmitting electricity to a down-hole device is provided. The wire-line section can comprise: a tubular sheath having first and second ends and forming a passageway therebetween; a conductor disposed within said passageway extending between said first and second ends; a first connector operatively attached to said conductor at said first end, said first connector operatively attached to said first end of said tubular sheath; a second connector operatively attached to said conductor at said second end, said first and second connectors configured to releasably connect with one another; and coupling means for releasably coupling said first connector with the second end of a second wire-line section whereupon releasably coupling said wire-line section to said second wire-line section, said first connector is releasably connected with the second connector of said second wire-line section. 
         [0006]    In one embodiment, the tubular sheath can have open first and second ends and can be made of suitable electrically insulating (non-conducting) material. In another embodiment, the tubular sheath can be made of polyvinylchloride. In a representative embodiment, the tubular sheath can be a polyvinylchloride pipe having a ¼-inch inside diameter. 
         [0007]    The conductor can be coaxially mounted within the passageway of the tubular sheath such that the tubular sheath protects and insulates the conductor. The conductor can be a single solid-core wire or a bundle of stranded wires of smaller gauge. The conductor can be made of any suitable conducting material such as, but not limited to, brass, copper, steel or aluminium. 
         [0008]    In another embodiment, the conductor can further comprise an insulating sheath. The insulating sheath can be disposed between said conductor and said tubular sheath in said passageway. In one embodiment, the insulating sheath can be made of suitable dielectric material including, but not limited to, polypropylene. In a representative embodiment, the conductor can be a 10-gauge insulated wire that fits within the passageway of the tubular sheath. 
         [0009]    In one embodiment, the first connector can comprise a socket. The second connector can comprise a plug that releasably connects with the socket to form an electrical connection between adjoining wire-line sections. Similar to the conductor, the socket and the plug can be made of any suitable conducting material such as, but not limited to, brass, copper, steel or aluminium. In another embodiment, the first connector can be a hollow brass stub connected to the conductor at one end and the second connector can be a banana plug connected to the other end of the conductor. The banana plug is configured to fit snugly in the hollow receptacle of the brass stub. In a representative embodiment, the conductor can be soldered to the brass stub and to the plug in a wire-line section. The brass stub can be partially inserted into the first end of the sheath whereby a portion of the stub can extend from the first end of the sheath. In one embodiment, the stub and the first end of the sheath can comprise complementary threads such that the stub is threaded into the first end of the sheath. It should be obvious to one skilled in the art that the stub can be attached to the sheath in any number of ways that include but are not limited to mechanical fasteners, friction fitting the stub into the sheath and use of adhesives to hold the stub in place. 
         [0010]    In yet another embodiment, the first connector can comprise a first conductive insert connected to the conductor at the first end of the sheath, and the second connector can comprise a second conductive insert connected to the other end of the conductor at the second end of the sheath. In further embodiments, the first and second inserts can be sealably affixed to the sheath with a suitable adhesive. In yet further embodiments, the first and second inserts can comprise complementary threads whereby the second insert of one wire-line section can be threaded into the first insert of a second wire-line section. 
         [0011]    In one embodiment, the length of the conductor can be selected such that the end of the plug is approximately flush with the end of the second end of the sheath where it houses and protects said plug. The length of the conductor can easily be selected by a person skilled in the art to allow for the expansion and contraction of the conductor and the sheath and maintain an electrical connection between a pair of first and second connectors having regard to the down-hole environmental conditions including but not limited to pressure and temperature. 
         [0012]    In another embodiment, the first connector can further comprise sealing means for providing a fluid-tight connection between releasably coupled first and second wire-line sections. In one embodiment, the sealing means can comprise an o-ring seal. In a representative embodiment, the first end of said tubular sheath can comprise a groove disposed about said first connector for receiving an o-ring. When a pair of wire-line sections is coupled together, the o-ring can be compressed thereby sealing the junction between the sheaths of the adjoining sections. 
         [0013]    As noted above, the first and second connectors are coupled together with coupling means. The coupling means can be any suitable mechanical coupling means known in the art including, but not limited to, frictional means and threadably engaging means. 
         [0014]    In one embodiment, the coupling means can include threads disposed about the exterior of the first connector and complementary threads disposed within said passageway at the second end of the sheath whereby a pair of wire-line sections can be coupled together by threading said first connector of a first wire-line section into the second end of a second wire-line section to couple said wire-line sections together. In so doing, the plug of one wire-line section can be inserted into the socket of the adjoining wire-line section. 
         [0015]    In another embodiment, the coupling means can include a bayonet connector disposed on the first connector and bayonet receiver means disposed within the passageway of a second end of another wire-line section for receiving said bayonet connector whereby said wire-line sections can be coupled together by inserting the bayonet connector into the bayonet receiver means of the second wire-line section and turning or twisting the bayonet connector to releasably lock the wire-line sections together. In so doing, the plug of one wire-line section can be inserted into the socket of the adjoining wire-line section. 
         [0016]    In another embodiment, the coupling means can include a quick connect plug disposed on a first connector and a quick connect coupler disposed on the second end of a second wire-line section similar to quick-release or locking ball connectors as used on air compressor connections and air hoses for use with pneumatic tools, as well known to those skilled in the art. In this manner, wire-line sections can be coupled together by inserting the quick connect plug of one wire-line section into the quick connect coupler of another wire-line section to lock the two together. In so doing, the plug of one wire-line section can be inserted into the socket of the adjoining wire-line section. 
         [0017]    In another embodiment, the wire-line connection system can include a device connector that can be incorporated in a down-hole tool to permit connection to the wire-line in order to provide electric power to the tool. In a representative embodiment, the device connector can comprise a second connector having a plug to connect to a socket on a first connector of a wire-line section. In a further embodiment, the wire-line connection system can include an entry sub-assembly that passes through a pipe to connect with a wire-line section disposed within the pipe to provide electric power to the wire-line connection system. 
         [0018]    In a representative embodiment, the wire-line system can include a plurality of wire-line sections connected to each other in series wherein one end of the connected wire-line sections can be coupled to a device connector mounted on a down-hole tool and wherein the other end of the connected wire-line sections can be coupled to an entry sub-assembly, which is in turn connected to a cable leading through an opening in the pipe to connect to a source of electric power to power the down-hole tool. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]      FIG. 1  is a side cross-sectional view depicting a wire-line section. 
           [0020]      FIG. 2  is a side cross-sectional view depicting the wire-line section of  FIG. 1  connected to a second wire-line section. 
           [0021]      FIG. 3  is a side cross-sectional view depicting the wire-line section of  FIG. 1  configured in a connection system to provide power to a down-hole tool. 
           [0022]      FIG. 4  is a side cross-sectional view depicting an alternate embodiment of a wire-line section having bayonet connectors. 
           [0023]      FIG. 5  is a side cross-sectional view depicting an alternate embodiment of a wire-line section having complementary connectors on opposing ends. 
       
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
       [0024]    Referring to  FIG. 1 , an embodiment of wire-line section  10  is shown. Wire-line section  10  includes sheath  12  that has a first or socket end  18  and a second or plug end  28  with passageway  13  extending therebetween. In a representative embodiment, sheath  12  can be made of polyvinylchloride pipe having an inside diameter of ¼-inch. In typical applications, the length of wire-line section  10  can be selected to extend up to the entire length of a section of well pipe or it can be of shorter lengths. 
         [0025]    Disposed within passageway  13  is conductor  22 . Conductor  22  can be made of any suitable conducting material. In a representative embodiment, conductor  22  can be made of copper or aluminum and can further be a solid-core wire or be made of multiple strands of smaller gauge wire. In another embodiment, conductor can further include insulating sheath  24 . In a representative embodiment, conductor  22  can be a length of 10-gauge insulated wire. 
         [0026]    At socket end  18 , socket  14  can be inserted into passageway  13  of sheath  12 . In one embodiment, socket  14  can comprise threads  26  that thread into complementary threads  27  within passageway  13 . Conductor  22  can be inserted into opening  15  of socket  14  and attached to socket  14 . Socket  14  can be made of any suitable electrically conducting material such as, but not limited to, copper, aluminum, brass or steel. In one embodiment, socket  14  can be crimped to conductor  22 . In another embodiment, socket  14  can be soldered to conductor  22 . In the illustrated embodiment, socket  14  can further comprise threads  34  on the end of socket  14  that extend from sheath  12 . Socket  14  can further comprise hollow receptacle  36  to receive a plug connector. In a representative embodiment, socket end  18  of sheath  12  can further comprise groove  20  to hold o-ring seal  16 . 
         [0027]    At plug end  28  of sheath  12 , conductor  22  can comprise a plug connector. In the illustrated embodiment, the plug connector can be banana plug  32 . Plug  32  can be made of any suitable electrically conducting material such as, but not limited to, copper, aluminum, brass or steel. Plug  32  can be attached to conductor  22 , either by crimping or soldering the two together. Plug end  28  of sheath  12  can further comprise threads  30  which are complementary to threads  34  on socket  14 . In a representative embodiment, the length of conductor  22  can be selected such that the end of plug  32  is approximately flush with plug end  28  of sheath  12 . 
         [0028]    Referring to  FIG. 2 , wire-line section  10   a  is shown connected to wire-line section  10   b . Socket  14  of section  10   b  can be threaded into plug end  28  of section  10   a . In the representative embodiment shown in  FIG. 2 , the sections can be threaded together until socket end  18  of section  10   b  abuts plug end  28  of section  10   a . In this fashion, o-ring seal  16  is compressed to seal the junction between the two sections and acts to prevent any substances from the well pipe entering the wire-line sections. As sections  10   a  and  10   b  are connected together, banana plug  32  can be inserted into receptacle  36  of socket  14  to provide an electrical connection between the two sections. 
         [0029]    Referring to  FIG. 3 , an example wire-line connection system is shown. One wire-line section  10  is shown disposed in pipe section  40  for illustrative purposes only. It should be obvious to a person skilled in the art that a plurality of pipe sections  10  can be connected together with an equal number of wire-line sections  10  disposed therein to form a continuous wire-line connection system. Shown in pipe section  50  is down-hole tool  54  comprising device connector  52 . Device connector  52  can be similar to plug end  28  of wire-line section  10  in that device connector  52  can comprise plug  32  and threads  30  within passageway  13  of sheath  12 . Device connector  52  can be connected to socket end  18  of a wire-line section  10  that, in turn, can be connected to a plurality of wire-line sections  10  in series. In one embodiment, device connector  52  can be a stand-alone connector that can be operatively attached to down-hole tool  54 . In another embodiment, device connector  52  can be integral to down-hole tool  54 . 
         [0030]    In pipe section  42  is entry sub-assembly  44  that can connect to the plug end  28  of the uppermost wire-line section  10 . Entry sub  44  can comprise socket end  18  of a wire-line section  10  and can connect to plug end  28  of the uppermost wire-line section  10 . Entry sub  44  can further comprise cable  48  that can pass through opening  46  in pipe section  42 . Cable  48  can be connected to a source of electrical power that passes through entry sub  44  and all subsequent wire-line sections  10  to device connector  52  on down-hole tool  54 . 
         [0031]    Referring to  FIG. 4 , an alternate embodiment of wire-line section  10  is shown. In this embodiment, plug end  28  can comprise flared end  56  having opening  57  and J-slot  58 . Flared end  56  can further comprise at least one groove  64  for holding o-ring  62 . In a representative embodiment, flared end  56  can comprise two grooves  64  within opening  57  for holding two o-rings  62 . The diameter of opening  57  can be sized to permit socket end  18  of another wire-line section  10  to be inserted into flared end  56  such that contact can be made between o-rings  62  and socket end  18  of the second wire-line section  10  to form a liquid-tight seal between the wire-line sections. Socket end  18  of wire-line section  10  can further comprise locking pin  60  situated on the outer surface of sheath  12 . When socket end  18  of wire-line section  10  is inserted into flared end  56  of another wire-line section  10 , locking pin  60  can slide into J-slot  58  as far as it can go whereupon one wire-line section  10  is twisted with respect to the other so that locking pin  60  can be secured in J-slot  58  as well known to those skilled in the art. In connecting wire-line sections together in this manner, wire-line sections can be assembled together quickly and securely. 
         [0032]    Referring to  FIG. 5 , another embodiment of wire-line section  10  is shown. In this embodiment, socket end  18  can comprise flared end  66  to accommodate receiving conductive socket insert  68 . Socket insert  68  can be made of any suitable electrically conducting material such as, but not limited to, copper, aluminum, brass or steel. In further embodiments, socket insert  68  can be sealably affixed to flared end  66  with a suitable adhesive to seal sheath  12  at socket end  18 . Conductor  22  can be connected to socket insert  68  and inserting a portion of conductor  22  into opening  82  and soldering the two together. Alternatively, socket insert  68  can be crimpled onto conductor  22 . At plug end  28 , conductive plug insert  70  can be inserted into flared end  56 . Plug insert  70  can be made of any suitable electrically conducting material such as, but not limited to, copper, aluminum, brass or steel. As described in the embodiments above, banana plug  32  can be soldered or crimped onto conductor  22 . When plug insert  70  is inserted into flared end  56 , banana plug  32  can slide into opening  78  to make the electrical connection with plug insert  70 . In one embodiment, plug insert  70  can be affixed to flared end  56  with a suitable adhesive to seal off sheath  12  at plug end  28 . 
         [0033]    In other embodiments, plug insert  70  can comprise groove  74  around the base of threaded portion  76  to hold o-ring  72 . O-ring  72  provides the sealing means between adjoining wire-line sections. To join two wire-line sections together, the threaded portion  76  of one section is threaded into the threaded opening  80  of socket insert  68  of a second section. It should be noted that the use of banana plug  32  and opening  78  on plug insert  70  is one of convenience in the manufacture of wire-line section  10  and not one of necessity. It should be obvious to those skilled in the art that conductor  22  can be electrically connected to plug insert  70  by extending opening  78  all the way through plug insert  70  to the end of threaded portion  76  where conductor  22  can extend through and be soldered or crimped to threaded portion  76 . It is also contemplated that a pin could be struck through threaded portion  76  and conductor  22  to make the electrical connection as well. 
         [0034]    Although a few embodiments have been shown and described, it will be appreciated by those skilled in the art that various changes and modifications might be made without departing from the scope of the invention. The terms and expressions used in the preceding specification have been used herein as terms of description and not of limitation, and there is no intention in the use of such terms and expressions of excluding equivalents of the features shown and described or portions thereof, it being recognized that the scope of the invention is defined and limited only by the claims that follow.