Downhole running cable having non-metallic conducting and load bearing wire

Abstract

A cable (100) is used for running a load between surface and downhole in a well. The cable includes one or more wires (110) composed of a non-metallic material. Each of the one or more wires (110) bears the load from the surface and electrically conducts between the surface and downhole. An insulating material (120) is disposed about the one or more wires (110) and insulates the electrical conduction. The non-metallic material includes a carbon nano-tube wire. A jacket (130) can be disposed about the insulating material (120), and the jacket (130) can be composed of a non-metallic material also, such as carbon nano-tube wire.

Claims

1. A cable system for running a load between surface and downhole of a well and for communicating with an electrical source between surface and downhole of the well, the cable system comprising: a cable having at least one core element disposed along a length of the cable, the at least one core element being composed of carbon nano-tube material and acting as at least one of (i) a load-bearing member bearing the load and (ii) a conductor conducting with the electrical source; a deployment unit directing the cable between a cable source and the well at surface and running the cable between surface and downhole; and at least one sensor monitoring electrical conductivity of the at least one core element under the load and detecting an increase in the conductivity due to strain of the downhole cable reaching an elevated level.

2. The cable system of claim 1, wherein the at least one core element comprises a first core element of the cable disposed along the length of the cable and composed of the carbon nano-tube material, the first core element acting as at least one of (i) the load-bearing member bearing the load and (ii) the conductor conducting with the electrical source.

3. The cable system of claim 2, wherein the cable comprises a second core element disposed along the length of the cable and composed of carbon nano-tube material, the second core element acting as only a load-bearing member, as only a conductor, or both a load-bearing member and a conductor of the cable.

4. The cable system of claim 2, wherein the first core element comprises at least one wire of the carbon nano-tube material; and wherein the cable comprises an insulator composed of electrically insulating material and disposed externally about the at least one wire.

5. The cable system of claim 4, wherein the cable comprises a jacket disposed externally about the insulator and forming an exterior of the cable, the jacket composed of a different material than the at least one wire and the insulator.

6. The cable system of claim 4, wherein the cable comprises a second core element disposed externally about the insulator along the length of the cable, the second core element composed of carbon nano-tube material.

7. The cable system of claim 6, wherein the second core element comprises a plurality of carbon nano-tube wires formed as a sheath about the insulator.

8. The cable system of claim 6, wherein the second core element acts as at least one of a load-bearing member and a conductor for the cable.

9. The cable system of claim 6, wherein the second core element forms an exterior of the cable; or wherein the cable comprises a jacket disposed about the second core element and forming the exterior of the cable.

10. The cable system of claim 2, wherein the first core element comprises a plurality of wires conductively isolated from one another by an insulator.

11. The cable system of claim 10, further comprising one or more fiber optic cables disposed with the wires in the insulator.

12. The cable system of claim 10, wherein at least some of the wires comprise different cross-sections from one another.

13. The cable system of claim 1, wherein the cable has a non-circular cross-section.

14. The cable system of claim 1, further comprising a tool disposed on the cable and deploying in the well as the load.

15. The cable system of claim 14, wherein the tool is selected from the group consisting of a logging tool, a wireline tool, a shifting tool, a pulling tool, and a mechanical jar.

16. The cable system of claim 14, wherein the tool comprises a downhole telemetry unit as the electrical source, and wherein the system comprises an uphole telemetry unit electrically communicating with the downhole telemetry unit via the at least one core element of the cable.

17. The cable system of claim 14, the cable system comprising: a stretch simulator coupled between the cable and the tool.

18. The cable system of claim 14, wherein the tool is disposed at a termination of the cable, the termination comprising: a cablehead defining a preconfigured weakpoint; a rope socket having a mechanical component mechanically engaging the first core element and a conductive component electrically engaging the first core element; or one or more fixtures mechanically engaging the first core element and one or more terminals electrically engaging the first core element.

19. The cable system of claim 14, wherein the tool comprises a logging unit detecting at least one characteristic downhole correlated to depth, and wherein the system comprises a depth unit disposed at surface and in electrical communication with the logging unit via the at least one core element of the cable.

20. The cable system of claim 1, wherein the deployment unit comprises an arm extending from adjacent the cable source to adjacent a sheave at the well, the arm feeding the cable along the arm between the cable source and the sheave.

21. The cable system of claim 20, wherein the deployment unit comprises a drum as the cable source.

22. The cable system of claim 20, wherein the arm comprises a guide thereon guiding the movement of the downhole cable fed along the arm.

23. The cable system of claim 20, wherein the arm is manipulatable to situate the cable directly from the source to the sheave.

24. The cable system of claim 20, wherein the deployment unit comprises a drum as the cable source, and wherein the arm comprises a guide thereon guiding the movement of the downhole cable fed along the arm.

25. The cable system of claim 1, wherein the at least one core element acts at least as the load-bearing member of the cable; and wherein the deployment unit monitors the conductivity of the load-bearing member and automatically stops operation in response to the strain reaching the elevated level of a breaking point of the load-bearing member.

26. The cable system of claim 1, wherein the at least one sensor comprises an electronic circuit detecting current or voltage of a signal communicated through the load-bearing member of the cable.

27. A cable system for running a load between surface and downhole of a well and for communicating with an electrical source between surface and downhole of the well, the cable system comprising: a cable having at least one core element disposed along a length of the cable, the at least one core element being composed of carbon nano-tube material and acting as at least one of (i) a load-bearing member bearing the load and (ii) a conductor conducting with the electrical source; a deployment unit directing the cable between a cable source and the well at surface and running the cable between surface and downhole; a load cell disposed downhole on the cable adjacent the load; and a tension unit disposed at surface and in electrical communication with the load cell via the at least one core element of the cable.

28. The cable system of claim 27, wherein the deployment unit comprises an arm extending from adjacent the cable source to adjacent a sheave at the well, the arm feeding the cable along the arm between the cable source and the sheave.

29. The cable system of claim 28, wherein the deployment unit comprises a drum as the cable source, and wherein the arm comprises a guide thereon guiding the movement of the downhole cable fed along the arm.

30. The cable system of claim 28, wherein the arm is manipulatable to situate the cable directly from the source to the sheave.

31. The cable system of claim 27, further comprising a tool disposed on the cable and deploying in the well as the load.

32. The cable system of claim 31, wherein the tool is disposed at a termination of the cable; and wherein the termination comprises: a cablehead defining a preconfigured weakpoint; a rope socket having a mechanical component mechanically engaging the at least one core element and a conductive component electrically engaging the at least one core element; or one or more fixtures mechanically engaging the at least one core element and one or more terminals electrically engaging the at least one core element.

33. The cable system of claim 31, wherein the tool comprises a downhole telemetry unit as the electrical source, and wherein the system comprises an uphole telemetry unit electrically communicating with the downhole telemetry unit via the at least one wire of the cable.

34. The cable system of claim 31, wherein the tool comprises a logging unit detecting at least one characteristic downhole correlated to depth, and wherein the system comprises a depth unit disposed at surface and in electrical communication with the logging unit via the at least one core element of the cable.

35. The cable system of claim 31, wherein the tool is selected from the group consisting of a logging tool, a wireline tool, a shifting tool, a pulling tool, and a mechanical jar.

36. The cable system of claim 27, wherein the at least one core element comprises a first core element of the cable disposed along the length of the cable and composed of carbon nano-tube material, the first core element acting as at least one of (i) the load-bearing member bearing the load and (ii) the conductor conducting with the electrical source.

37. The cable system of claim 36, wherein the cable comprises a second core element disposed along the length of the cable and composed of carbon nano-tube material, the second core element being electrically insulated from the first core element and being only a load-bearing member of the cable, only a conductor of the cable, or both a load-bearing member and a conductor of the cable.

38. The cable system of claim 27, wherein the tension unit receives a reading communicated directly from the load cell measuring strain and determines a value of the load directly from the measured strain.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 illustrates a typical rig up system for running cable downhole for various purposes.

(2) FIG. 2 shows a measuring device that can measure depth and tension for the rig up system.

(3) FIG. 3A illustrates a cross-sectional view of a cable according to the prior art.

(4) FIG. 3B illustrates a cross-sectional view of a mono-core cased hole cable according to the prior art.

(5) FIG. 3C illustrates a cross-sectional view of a conventional slickline cable according to the prior art.

(6) FIG. 3D illustrates a cross-sectional view of a coated slickline according to the prior art.

(7) FIG. 3E illustrates a cross-sectional view of another prior art conductive slickline for oilfield use.

(8) FIG. 3F illustrates a cross-sectional view of an electrical cable according to the prior art having a solid core conductor, a surrounding electrically insulating layer, and a conductive tubular metal outer cover.

(9) FIG. 3G illustrates a slickline cable according to the prior art having of a solid wire core, an inner coating or jacket, and an outer coating or jacket.

(10) FIG. 3H illustrates a slickline cable according to the prior art having a conductive shield between inner and outer coatings.

(11) FIG. 3I illustrates a slickline cable according to the prior art having a hard jacketed cable.

(12) FIG. 4 illustrates a rig up system for running cable of the present disclosure downhole for various purposes.

(13) FIG. 5A illustrates a schematic of a communication arrangement for the disclosed cable.

(14) FIG. 5B illustrates a schematic of a tension monitoring arrangement for the disclosed cable.

(15) FIG. 5C illustrates a schematic of a depth monitoring arrangement for the disclosed cable.

(16) FIG. 5D illustrates a schematic of another depth monitoring arrangement for the disclosed cable.

(17) FIG. 6A illustrates a cross-sectional view of a non-metallic cable according to the present disclosure for use as slickline, electric wireline (e-line), braided line, Heavy Duty Wireline Fishing (HDWF) line, or the like for downhole applications in a well.

(18) FIG. 6B illustrates a cross-sectional view of an alternative arrangement of the disclosed cable having an optional outer sheath, which can be composed of plastic or the like.

(19) FIG. 6C illustrates a cross-sectional view of yet another arrangement of the disclosed cable having fiber optic cables disposed in the cable, for example, inside or near a grouping of the carbon nano-tube wires.

(20) FIGS. 6D to 6J illustrate cross-sectional views of yet additional arrangements of the disclosed cable.

(21) FIGS. 7A-7B illustrate exemplary toolstrings for deployment downhole on the cable to perform some type of operation.

(22) FIG. 8 illustrates a cross-sectional view of a cable termination using a threaded rope socket.

(23) FIGS. 9A-9C illustrate various other cable terminations that can be used with the disclosed cable.

(24) FIG. 10 illustrates a stretch simulator or accelerator for installing on a toolstring immediately below a rope socket for the disclosed cable.

DETAILED DESCRIPTION OF THE DISCLOSURE

(25) FIG. 4 illustrates a rig up system 10 for running cable 100 of the present disclosure downhole for various purposes. The cable 100 of the present disclosure has at least one carbon nano-tube core element acting as either one or both of a load-bearing member and a conductor for the cable. Further details of the configuration of the cable 100 are discussed later.

(26) In the rig up system 10, the cable 100 passes from a drum 22 in a deployment unit 20 to an arm 80, which directs the cable 100 to the sheave 32 on the stuffing box 34. The arm 80 can be manipulated using crane components (not shown) or the like to situate the cable 100 more directly from the unit 20 to the Christmas tree 30 and can include a guide unit 82, rollers, goose neck, and the like. The guide unit 82 can also include a conventional system for determining the length of cable 100 paid out and tension on the line.

(27) The cable 100 enters the stuffing box 34 and passes through a lubricator 36 to a secondary barrier 38 or blow out preventer. If desired, a load sensor could be used at the mounting of the sheave 32 to the stuffing box 34. However, the load cell may be used in its conventional location at a winch unit or elsewhere.

(28) Eventually, the cable 100 passes to the Christmas tree 40 through the swab and master valves 42, and then to the well for its intended purposes. Various other components are used with the system 10 as well, but are not described here. When the cable 100 is used for intervention, for example, the rig up system 10 may include cable cutter subs, a tool trap, a tool catcher, check valves, etc.

(29) The cable 100 having the carbon nano-tube core element as the load bearing and conductive member has a smooth, impermeable outer surface so the rig up system 10 can use the stuffing box 34 to pack off around the cable 100. A grease injection system may not be needed, although it could be used when necessary. Additionally, due to the inert nature of the disclosed cable 100, a chemical injection sub 34 for coating corrosive resistant material on the cable 100 may not be used, although it could be used if necessary.

(30) As before, the rig up's deployment unit 20 can be skid-mounted on the rig or can be part of a deployment truck. The unit 20 stores the cable 100 on the drum 24 that feeds the cable 100 in and out of the unit 20. A winch for the drum 24 typically has a hydraulic drive powered by a diesel engine or electric power pack that drives the drum 24 to feed or pull the cable 100. The unit 20 may also include communication, tension, and depth systems.

(31) FIG. 5A illustrates a schematic of a communication arrangement for the disclosed cable 100. Uphole and downhole telemetry units 80U-D communicate electrical signals with one another along the cable 100 since the carbon nano-tube wire of the cable 100 is a conductor as well as load bearing. Although not shown, the cable 100 may also conduct electrical power.

(32) FIG. 5B illustrates a schematic of a tension monitoring arrangement for the disclosed cable 100. A tension unit 150 disposed at surface with the drum 24 monitors the tension by communicating with a load cell or strain gauge 152 disposed downhole on the cable 100 at or near a downhole tool or cable termination (not shown) on the cable 100. Because the cable's carbon nano-tube wire is both load bearing and conductive, signals from the load cell 152 can readily be communicated to the tension unit 150 at the surface.

(33) Being disposed on the end of the carbon cable 100, the load cell or strain gauge 152 can measure strain directly at the termination. Readings from the cell 152 can then be communicated directly uphole via the cable 100 so operators at the surface can know the actual loads on the cable 100 at a tool (not shown), rather than needing to infer the load at the tool from strain measurements at the surface and characterization of the cable's behavior.

(34) FIG. 5C illustrates a schematic of a depth monitoring arrangement for the disclosed cable 100. A downhole tool 200, such as a logging unit, detects characteristics of the borehole 12, such as its lithography, transitions, etc., which have been correlated with a depth in the borehole 12. Detected characteristics from the tool 200 are communicated through the cable 100 to the depth unit 160 at the surface. The depth unit 160, in turn, determines the depth of the tool 200 in the borehole 12 and the length of the cable 100 deployed.

(35) In addition to using logging characteristics for depth correlation, other measures could be used. For example, casing collar location and other comparable techniques could also be used to correlate the length of the cable 100 based on the depth of the tool 200. As such, the tool 200 can include a casing collar locator to locate collars 14 in the casing.

(36) FIG. 5D illustrates a schematic of another depth monitoring arrangement for the disclosed cable 100. The cable 100 has a plurality of markers 172 disposed along its length at known separations. As will be discussed below, the cable 100 having the carbon nano-tube wire is not subject to extensive elongation during use so the distance between markers 172 can be relatively consistent along the length of the cable 100.

(37) A marker detector 174 reads the markers 172 in the non-metallic cable 100 and infers the depth of any tool deployed thereon. The markers 172 can be metallic elements disposed in the non-metallic cable 100 so the detector 174 can sense a change in magnetic field associated with the passing marker 172. Other forms of detection can be used, including electrical, optical, Radio Frequency Identification, and the like.

(38) A speed detector 178 associated with the drum 24 determines and records the speed of the pay out of the cable 100 using know techniques, and a clock 176 measures a time between signals from the markers 172. Based on the time between signals and the spooling speed of the cable 100, a depth unit 170 can determine the length of the cable 100 paid out, which can infer the depth of any tool on the cable 100 in the borehole.

(39) Depth determination and control with a conventional cable is difficult because the cable tends to stretch substantially. Additionally, wire slippage is common in slickline operations. Here, the stretch of the disclosed cable 100 can be as low as less than 1-ft per 1000-ft downhole so depth downhole can be determined rather directly without much accounting for stretch and variation along the length of the disclosed cable 100. Embodiments of devices for determining depth are disclosed in co-pending PCT application entitled Downhole Running Cable Depth Measurement by Bradley J. McFarland, Andrew J. Baker, and George J. Rodger, which is filed herewith and is incorporated herein by reference in its entirety.

(40) Having a general understanding of the disclosed cable 100 with the carbon nano-tube wire for load bearing and conducting, discussion now turns to particular constructions of the disclosed cable 100 and the arrangement of non-metallic, carbon nano-tube core elements making up its load bearing and conductive elements.

(41) FIG. 6A illustrates a non-metallic cable 100 according to the present disclosure for use as a slickline, an electric wireline (e-line), a braided line, a Heavy Duty Wireline Fishing (HDWF) line, or the like for downhole applications in a well. The cable 100 uses carbon nano-tube wire 110 as at least one core element acting as the load bearing member and as the conductor for the cable 100. In the sense used herein, a load-bearing member at least describes the component or components of the disclosed cable 100 that collectively carry the bulk of the tensile load to which the cable 100 is subjected due to weight of a tool, pulling action, jarring, etc. As discussed previously, the cable 100 can be used for depth correlations and can pass signals or power. Thus, a conductor as used here in at least describes a component or components of the cable for conducting electrical power, signals, telemetry, etc.

(42) In the depicted arrangement, the cable 100 includes three carbon nano-tube wires 110 insulated by an insulator of insulating material 120. In general, the cable 100 can have one or more carbon nano-tube wires 110, and three are shown merely for illustration. The insulating material for the insulator 120 can be PEEK, nylon, or other suitable material for electrical isolation and flexibility.

(43) The carbon nano-tube wires 110 can be profiled as shown to form a more circular cross-section to the cable 100 when positioned together, although this is not strictly necessary as any shape can be used. For example, the wires 110 can have a conventional circular cross-section and can still fit together into a cable having a circular cross-section. However, because the carbon nano-tube wires 110 are formed differently than conventional wires, they can be more readily formed with profiled shapes so that when fit together the wires 110 give more cross-sectional wire area inside a set diameter of the resulting cable 100.

(44) The cable 100 also includes a jacket armor 130 of carbon nano-tube material that is the same or different than that used for the wires 110. This jacket armor 130 preferably forms a smooth outer surface so the cable 100 can be used without the need for a grease injection system. For example, the smooth outer surface can be formed by a braiding or weave of carbon nano-tube wire for the jacket armor 130 around the inner insulation material 120 and inner wires 110.

(45) One particular source of carbon nano-tube material is CurTran LLC of Houston, Tex. The inner load and conductor wires 110 can be formed as continuous strands from carbon nano-tube in a wire forming process. In general, the wire forming process produces filaments, which are then processed to form the desired wire size. Run together to form the core of the final cable 100, the wires 110 are extruded with the insulation material 120. Finally, the jacket armor 130 is braided, woven, wound, or otherwise formed around the outside of the insulated core for the disclosed cable 100.

(46) As noted here in, the carbon nano-tube wire 110 is a non-metallic conductor and load bearing member for the cable 100. Compared to other conductors and load bearing wires, the carbon nano-tube wire 110 for the disclosed cable 100 has a number of advantages. For conductivity, the wire 110 has low resistance, making it a good conductor of electricity, and the wire 110 has low impedance, which can reduce power losses. The wire 110 can also be well-suited for signal transmission and reduced noise.

(47) As to mechanical properties, the wire 110 is light-weight and has a low coefficient of thermal expansion (CTE), and the wire 110 is composed of a non-corrosive and inert material for use in harsh environments, such as a wellbore. Additionally, the wire 110 has high-strength and is not subject to the same issues of fatigue as other wires.

(48) As noted herein, the cable 100 conveys tools and equipment into and out of a wellbore. To do this, the cable 100 has the non-metallic wire 110 as the principal load bearing member. Moreover, the load-bearing member can also be a conductor for the cable 100. Accordingly, the conductors and the load bearing members 110 of the cable 100 are one and the same and, hence, have the same tensile strength and conductivity, unlike the conventional cables whose copper conductor is different in tensile strength than the steal wires.

(49) In general, the cable 100 can have one or more load bearing members and in turn can have one or more conductors. In one embodiment, one of the load bearing members is the external jacket armor 130, which can also be a conductor if desired. Additionally, electrical current can be passed through the load-bearing conductor(s) 110. In this way, electrical signals can be sent from surface to control downhole devices coupled to the cable 100. Likewise, electrical signals can be sent from downhole to surface to transfer information.

(50) Typical sizes of the cable 100 can be comparable to those sizes used in conventional applications, although the cable 100 in general can be smaller for the same application. The cable 100 can be of any desired length, such as 25,000-ft. Rather than being just a material reinforced with carbon nano-tubes, the disclosed cable 100 is continuous, and the load bearing wires 110 are composed almost entirely of carbon, except for the small amount of void space.

(51) During loading, the cable 100 stays in the elastic region so the cable 100 does not suffer from some of the restrictions of conventional cables, such as bend restrictions, etc. Therefore, the disclosed cable 100 can use tighter bend radii, drums, smaller sheaves, etc., during deployment and use.

(52) Because conventional cables can fatigue, their use needs to be logged. However, the disclosed cable does not suffer from such fatigue. The demands for monitoring the disclosed cable 100 are less rigorous.

(53) It is possible for the disclosed cable 100 to fail, however. This can be detected using the electrical properties of the disclosed cable 100. When the cable 100 is subjected to loads, for example, the breaking level of the disclosed cable 100 may be reached or surpassed depending on operations and circumstances. As the disclosed cable 100 reaches its maximum load, the electrical conductivity of the cable 100 increases. This is due in part to the further compaction of the void space in the carbon nano-tube structure of the wire 110 when subjected to increased load.

(54) By monitoring the electrical conductivity of the cable 100 during use, sensors at surface or elsewhere can detect the increase in conductivity should the cable 100 begin to reach its breaking point. For example, a sensor electrically connected to the cable 100 at the deployment unit (20) can sense the conduct of the cable 100 in a number of ways. Such a sensor can include an electronic circuit to detect current, voltage, etc. of a signal communicated through the load-bearing member of the cable 100 so the conductivity can be determined. If a threshold is reached, the deployment unit (20) can then automatically stop operations. Overall, the disclosed cable 100 can be operated at levels closer to its breaking strain because the cable 100 does not fatigue in the same way as a conventional metallic cable.

(55) FIG. 6B shows an alternative arrangement of the disclosed cable 100 having an optional outer sheath 140, which can be composed of plastic or the like. Such an outer sheath 140 may be unnecessary in most cases because the jacket armor 130 of carbon nano-tube wire on the disclosed cable 100 is practically impermeable.

(56) FIG. 6C shows yet another arrangement of the disclosed cable 100 having fiber optic cables 115 disposed in the cable 100, for example, inside or near the grouping of the nano-tube wires 110. The fiber optic cables 115 can be used to send signals to tools downhole.

(57) FIGS. 6D to 6F illustrate cross-sectional views of yet additional arrangements of the disclosed cable 100. In FIG. 6D, the cable 100 includes a single load bearing member/conductor in the form of a carbon nano-tube wire 110. This may be surrounded by an outer insulator or sheathing 120.

(58) The cable 100 in FIG. 6E is similar and includes a central load-bearing/conductor member in the form of a carbon nano-tube wire 100. The cable 100 in FIG. 6F is similar and includes two central wires 110. In both cases, a jacket armor 130 of carbon nano-tube wire 130 can be disposed about intermediate insulating material 120. This jacket armor 130 can also be a load bearing member and/or conductor according to the purposes disclosed herein. As shown in FIG. 6G, additional layers of insulation 120 and jacket armor 130 can also be formed about the wires 110 and layers depicted in FIGS. 6E-6F to create cables 100 with ever increasing diameters and additional load bearing members and conductors.

(59) The cables 100 depicted above have been circular in cross-section because this is the typical configuration and may be the most convenient. This is not strictly necessary. For example, FIG. 6H shows a cross-section of a cable 100 having a multisided cross-section. Moreover, FIG. 6I even shows a cable 100 having a flattened cross-section. Multiple inner wires 110 are disposed side-by-side one another and are encased in insulating material 120. An outer jacket armor 130 can also be provided that is formed of carbon nano-tube. FIG. 6J illustrates a cable 100 having various wires 112A-C with at least some wires (e.g., 112C) having different cross-sections from other wires (e.g., 112B). In another alternative, FIG. 6J shows how one wire 112A as one core element can be separated by an insulator 112B surrounded by a second core element of a plurality of carbon nano-tube wires 112C formed as a sheath about the insulator 112B.

(60) Such alternative shapes for the cable 100 as in FIGS. 6H-6I can have a number of advantages for particular implementations. For example, the multisided cable 100 of FIG. 6H may have particular sealing advantages as it is run through a stuffing box or the like. The flattened cable 100 of FIG. 6I can be wound on a reel and potentially take up less space, and the cable 100 could be deployed and situated downhole to take up less cross-sectional area, potentially increasing flow or passage of tools.

(61) Turning now to the cable's termination, the end of the cable 100 is used downhole for various purposes and may holding a logging tool, wireline tool, shifting tool, pulling tool, etc. The end of the cable 100 is therefore terminated to connect the cable 100 to such downhole tools or components. FIGS. 7A-7B show examples of some of the components that can be supported on the end of the cable 100.

(62) FIG. 7A shows an exemplary toolstring 200 for deployment downhole on the cable 100 to perform some type of operation. In slickline work, the string 200 is run, manipulated, and retrieved by the upward or downward movement of the cable 100, which is itself raised and lowered by the winch and other components at the surface.

(63) A cable termination 210 connects to the cable 100 to the toolstring 200. For its part, the toolstring 200 can have any number of basic components 202, 204, etc. according to the type of operation undertaken, and the precise configuration of the toolstring 200 is contingent on factors such as job type, access, hole deviation, depth pressure, completion type, log history, etc.

(64) FIG. 7B shows another exemplary tool string 220 for deployment on the cable 100. This tool string 220 is a workstring having a wireline stem 212, mechanical jars 224, and a knuckle joint 226 for performing slickline operations. Other forms of workstrings can be used with the cable 100.

(65) As noted above, the end of the cable 100 is terminated with a cablehead 210, which connects to tools for the intended proposes in the well. The termination 210 provides three basic functions, including mechanical/electrical connection, a fish-neck for retrieval, and a preconfigured weakpoint. The termination 210 incorporates a fishing neck at its top end. This allows a fishing tool to latch on to a stuck or dropped toolstring to fish it from the well.

(66) In one embodiment, the cable termination 210 uses a threaded rope socket as shown in FIG. 8A. A portion at the end of the cable 100 is attached or affixed at 214 to a fishneck 212 using a variety of techniques. A threaded end 216 of the fishneck 212 threads into a rope socket 214, and a conductive or transmissive component 217 of the affixation (or of the cable 100 itself) connects to internal components 215 of the rope socket 218 for establishing an electrical, optical, communicative, or other type of connection. This conductive or transmissive component 217 may have a backup mechanical connection (not shown) inside the socket 218.

(67) Another cable termination 240 is schematically shown in FIG. 8B. The multiple wires 111 of the cable 100 (if present) branch off from one another either side-by-side as shown or inside and outside one another in a concentric arrangement. These wires 110 can be the internal wires (e.g., 110: FIGS. 6A-6I) and can also be the outer jackets (e.g., 130: FIGS. 6A-6I). Mechanical fixtures 242 engage the wires 111 to mechanically support the cable 100. The fixtures 242 can include slips or the like.

(68) Terminals 244 at the end of the wires 111 then connect by electrical lines to the tool's internal components 246. Secondary electrical connections can also be provided via the mechanical fixtures 242, which can connect by electrical lines to terminals 248 for appropriate connection to the tool's internal components 246.

(69) In addition to the above, a slickline rope socket 210 and several other terminations and cableheads can be used, including a pear drop rope socket, a knot type rope socket, a releasable rope socket, and a braided line rope socket.

(70) For example, the termination shown in FIG. 9A can be similar to a braided line rope socket 210 having a slip assemblye.g., a cone and a washer system. The specially designed slip assembly secures the wire (not shown) to the rope socket 210, and line tension increases the grip of the rope socket 210 to the wire.

(71) In the pear drop rope socket 210 shown in FIG. 9B, the wire is wrapped around a groove in a pear drop and is wedged in a taper between the tear drop and a mating sleeve. This wedge action grips the wire (not shown) and is proportional to the tension applied to the wire.

(72) In the knot type rope socket 210 shown in FIG. 9C, a traditional slickline knot is used, and the knot can be tied to allow the rope socket 210 to break at a predetermined pull. The knot type rope socket 210 consists of a body, a spring, a spring support, and a disc. The wire (not shown) is bent around the disc then wound around itself a number of turns dependent upon the required weak point value required.

(73) Such a releasable rope socket 210 can be used for either slick or braided type slickline and is designed to release only in the event that the toolstring becomes stuck downhole. The socket 210 is activated by a drop bar which is dropped down the cable (not shown) in a similar manner to a go-devil or snipper. When the drop bar contacts the release trigger, the collet releases the lower fishing neck. The upper housing and drop bar are retrieved to surface leaving a clean fishing neck.

(74) The braided line rope socket 210 can be an overload type or a plain type of socket. The overload type is designed to release by causing the line to break under severe loading at a specific percentage of the full strength of the line. The plain type is designed without the overload release feature.

(75) Because the disclosed cable 100 has such limited stretch, deployment and use of the cable 100 in some implementations may use stretch simulators or accelerators to facilitate operations. The stretch simulator or accelerator can be installed on a toolstring (200, 220) immediately below the rope socket (210). The accelerator can be installed primarily when spring/hydraulic jars are to be used on the workstring (220). The spring replaces the stretch of the cable 100 which exists when jarring up. The accelerator reduces the shock-loading at the rope socket 210 and can cause the stem to accelerate faster when the spring/hydraulic jars go off. This creates a more effective impact.

(76) As shown in FIG. 10, for example, a stretch simulator or accelerator 230 has a top section 232, a bottom section 234, and a spring or beveled washers 236 between them. The accelerator 230 works by the cable (100) pulling on the top section 232 while the bottom section 234 is held by a pulling tool (not shown). The beveled washers 236 are compressed, and as the jar (224) below fires, the beveled washers 236 expand which in turn accelerates the toolstring giving more impact.

(77) The foregoing description of preferred and other embodiments is not intended to limit or restrict the scope or applicability of the inventive concepts conceived of by the Applicants. It will be appreciated with the benefit of the present disclosure that features described above in accordance with any embodiment or aspect of the disclosed subject matter can be utilized, either alone or in combination, with any other described feature, in any other embodiment or aspect of the disclosed subject matter.

(78) In exchange for disclosing the inventive concepts contained herein, the Applicants desire all patent rights afforded by the appended claims. Therefore, it is intended that the appended claims include all modifications and alterations to the full extent that they come within the scope of the following claims or the equivalents thereof.