Wireline release tool

Abstract

A wireline release tool is described herein featuring a removable energetic module for use in downhole wireline operations. The removable energetic module is housed within an energetic assembly of the release tool and includes an electrically activated ignitor, booster charge, and control module. The module is configured to be independently installed, replaced, or rearmed using a threaded cartridge plug interface. The release tool further includes a first part connectable to an upper wireline portion and a second part connectable to a lower downhole tool assembly. The first part includes a coupling structure having collet fingers and a piston collar that together form a release mechanism. In operation, a firing signal transmitted through the wireline activates the removable energetic module, generating an output that displaces the piston collar to release the collet fingers, thereby separating the lower downhole tool assembly from the wireline.

Description

WIRELINE RELEASE TOOLTECHNICAL FIELD

[0001] The present invention relates to a wireline release tool for use in oil and gas wireline operations.BACKGROUND

[0002] In oil and gas exploration and production, wireline operations are crucial for the deployment, retrieval, and maintenance of various downhole tools and equipment. These operations involve running tools into and out of the wellbore on a wireline or slickline cable. However, during the course of such operations, it is not uncommon for tools or equipment to become stuck due to mechanical failure, formation issues, debris accumulation, or other unforeseen factors.

[0003] When a tool becomes stuck, it can cause significant delays and increased costs due to the need for time-consuming and often complex retrieval operations. Conventional methods for addressing stuck tools typically involve the use of fishing tools or other mechanical means, which can be both labor-intensive and expensive. In certain cases, these methods may prove ineffective, requiring the dismantling and removal of the entire wireline string, further exacerbating operational inefficiencies and risks.

[0004] To address these challenges, the industry has developed various techniques and tools designed to facilitate the release of stuck equipment. Among these, release tools have emerged as one solution due to their ability to deliver a controlled explosive force that can effectively release stuck tools without necessitating the complete removal of the wireline string.

[0005] Despite the advantages offered by ballistic release tools, there remains a need for improved designs that enhance safety, precision, and operational efficiency. Existing tools may face limitations in terms of control over the explosive force, reliability of the activation mechanism, clean release, and adaptability to various downhole conditions. Therefore, ongoing innovation in this area is essential to address these limitations and improve the overall effectiveness of wireline operations.SUMMARY OF THE INVENTION

[0006] A release tool for a wireline toolstring is provided. The release tool includes a first part. The first part is configured for connection to an upper wireline portion. The first part includes an electrical contact assembly configured to receive a firing signal. The first part further includes a first coupling structure. The release tool includes a second part. The second part is configured for connection to a lower downhole tool assembly. The second part includes a second coupling structure configured to releasably couple with the first coupling structure. The release tool includes an energetic assembly including a removable energetic module configured to be replaced independently of the second part.

[0007] A wireline toolstring for downhole operations is also provided. The wireline toolstring includes an upper wireline portion configured to transmit electrical signals from a surface control system. The wireline toolstring includes the release tool connected to the upper wireline portion. The wireline toolstring includes a lower downhole tool assembly connected to the release tool.

[0008] A method of releasing a lower downhole tool assembly from a wireline toolstring using the release tool is further provided. The method includes transmitting a firing signal from a surface control system through the wireline toolstring to the release tool. The method also includes activating the removable energetic module disposed in the second part of the release tool in response to the firing signal. The second part is thereby released from the first part such that the lower downhole tool assembly separates from the wireline toolstring.BRIEF DESCRIPTION OF THE DRAWING

[0009] FIG. 1 is a perspective view of the release tool according to one embodiment.

[0010] FIG. 2 is a side cross-section view of the release tool.

[0011] FIG. 3 is a zoomed-in cross-section view of the coupling of a first coupling portion of a first part and a second coupling portion of a second part of the release tool in a retaining position.

[0012] FIG. 4 is a zoomed-in cross-section view of the coupling of the first coupling portion of the first part and the second coupling portion of the second part in a relaxed position.

[0013] FIG. 5 is a perspective view of the first part of the release tool.

[0014] FIG. 6 is a side cross-section view of the first part of the release tool.

[0015] FIG. 7 is an exploded side view of the first part of the release tool.

[0016] FIG. 8 is a perspective view of the second part of the release tool.

[0017] FIG. 9 is a side cross-section view of the second part of the release tool.

[0018] FIG. 10 is an exploded perspective view of the second part of the release tool.

[0019] FIG. 11 is a first perspective view of a removable energetic module of the release tool.

[0020] FIG. 12 is a second perspective view of the removable energetic module of the release tool.

[0021] FIG. 13 is a third perspective view of the removable energetic module of the release tool.

[0022] FIG. 14 is a schematic depiction of a wireline toolstring in use for downhole operations.DETAILED DESCRIPTION

[0023] A release tool according to one embodiment is provided for use with a wireline toolstring and is generally designated 10. The release tool 10 is depicted in FIGS. 1-14, and is depicted generally in FIGS. 1-3. The release tool includes a first part 100 and a second part 200. The first part 100 is configured for a connection to an upper wireline portion UWP. The first part 100 includes an electrical contact assembly 110 and a first coupling structure 160. The electrical contact assembly 110 is configured to receive a firing signal. The second part 200 is configured for connection to a lower downhole tool assembly LDTA. The second part 200 includes a second coupling structure 210. The second coupling structure 210 is configured to releasably couple with the first coupling structure 160. The second part 200 includes an energetic assembly 260 including a removable energetic module 262 configured to be replaced independently of the second part 200.

[0024] The release tool 10 includes a first part 100. The first part 100 is specificallydepicted in at least FIGS. 5-7. The first part 100 includes an electrical contact assembly 110. The electrical contact assembly 110 is configured to receive a firing signal. The electrical contact assembly 110 may be a top sub 110. The top sub 1 10 includes a body 112. The body 112 may define wrench flats or gripping surfaces 114 that facilitate make-up and break-out of the release tool 10 during assembly or maintenance operations. A top seal interface 116 and a bottom seal interface 118 extend from the body 112. The top seal interface 116 and the bottom seal interface 1 18 each include one or more grooves 120 to receive corresponding gaskets 122 (e.g., O-rings), which are configured to form pressure-tight seals with other elements of the release tool 10 or wireline. A top threading 124 extends from the top seal interface 116 and a bottom threading 126 extends from the bottom seal interface 118. The top sub 110 defines a cavity 128 along the axis A of the release tool 10. The cavity 128 is dimensioned to house a connecting rod 130. A connecting pin 132 contacts the connecting rod 130 and is arranged at an end of the top sub 110 proximate the top threading 124. The connecting pin 132 is configured to establish an electrical pathway between the upper wireline portion UWP and the release tool 10 for the firing signal. The connecting pin 132 is a spring contact pin 132 comprising a spring 134 allowing for axial movement to accommodate dimensional variations to maintain reliable electrical contact.

[0025] The first part 100 further includes a first coupling structure 160. The first coupling structure 160 includes a sleeve 162 with a plurality of axially slotted collet fingers 164 circumferentially spaced about and defining a recess 166. The first coupling slruclure 160 includes a piston collar 168 disposed coaxially around the collet fingers 164. The piston collar 168 is slidable between a first position and a second position. In the first position, an inner surface 170 of the piston collar 168 overlies the collet fingers 164 such that the collet fingers 164 are radially compressed inward to a retaining position. The retaining position is depicted in FIG. 3. In the second position, the inner surface 170 of the piston collar 168 is axially displaced from the collet fingers 164 such that the collet fingers 164 rest in a release position. The release position is depicted in FIG. 4. The sleeve 162 or the piston collar 168 may define a seal groove 172. In the exemplary embodiment, the sleeve 162 and the piston collar 168 each define a pair of seal grooves 172. A piston seal 174 is disposed within each seal groove 172 such that a piston seal 174 is disposed between the piston collar 168 and the sleeve 162. The first coupling structure 160 generally includes a coupling housing 176. Both the sleeve 162 and the coupling housing 176 are threadedly couplable to the top sub 110. The piston collar 168 is disposed between the sleeve 162 and the coupling housing 176. The coupling housing 176further defines a first stepped keyway 178 for engagement with the second part 200 of the release tool 10. The first coupling portion 160 comprises a spring contact activation pin 180. The spring contact activation pin 180 is configured to establish an electrical connection with the energetic assembly 260 via physical contact with the second part 200 such that the firing signal can activate the removable energetic module 262. The spring contact activation pin 180 comprises a spring 182 allowing for axial movement to accommodate dimensional variations to maintain reliable electrical contact.

[0026] The release tool 10 includes a second part 200. The second part is generally depicte d in FIGS. 8-10. The second part 200 is configured for connection to a lower downhole tool assembly LDTA. The second part 200 includes a second coupling structure 210. The second coupling structure 210 includes a neck 212 configured to be received within the recess 166 of the first coupling structure 160. The neck 212 defines a detent 214 (or a series of detents, or a groove) engageable by the collet fingers 164 of the first coupling structure 160. The piston collar 168 of the first coupling structure 160 is configured such that in the first position the collet fingers 164 radially engage the detent 214 of the neck 212 such that the first part 100 and the second part 200 are releasably retained. When the piston collar 168 of the first coupling structure 160 is displaced from the first position into the second position the collet fingers 164 move into the release position and radially disengage from the detent 214 of the neck 212. The first part 100 and the second part 200 are then releasable.

[0027] The second coupling structure 210 defines a shoulder 216 extending from a body 218 of the second coupling structure 210. The shoulder 216 is configured to contact the coupling housing 176 of the first coupling structure 160 when the first part 100 and the second part 200 are coupled. The shoulder 216 defines a second stepped key way 220. The second stepped key way 220 is configured to interface with the first stepped keyway 178 of the first part 100. The body 218 of the second coupling structure 210 may define wrench flats or gripping surfaces 222 that facilitate make-up and break-out of the release tool 10 during assembly or maintenance operations.

[0028] The second coupling structure 210 defines an energetic cavity 224 and the second part 200 comprises an energetic assembly 260. The energetic assembly 260 includes a removable energetic module 262 configured to be replaced independently of the second part 200 of the release tool 10. The energetic assembly 260 further includes a threaded cartridge plug 264. The cartridge plug 264 is configured to threadedly interface with a threaded femaleportion 226 of the second coupling structure 210 of the second part 200. The threaded interface between the cartridge plug 264 and the threaded female portion 226 is configured to retain the removable energetic module 262 within the energetic cavity 224 of the second part 200. The cartridge plug 264 generally defines an energetic module receptacle 266 configured to receive the removable energetic module 262. It will be appreciated that the removable energetic module 262 may be removed, reinstalled, or exchanged from the second part 200 by unthreading the cartridge plug 264 from the threaded female portion 226 of the second coupling structure 210. Once the same or different removable energetic module 262 is ready for installation, the removable energetic module 262 is disposed in the energetic cavity 224 and the cartridge plug 264 is threadedly recoupled with the threaded female portion 226 to resecure the removable energetic module 262 within the energetic cavity 224.

[0029] The energetic assembly 260 includes the removable energetic module 262. Both the energetic assembly 260 and the removable energetic module 262 are depicted in FIGS. 11-13. The removable energetic module 262 defines an energetic housing 268. The energetic housing 268 houses an energetic initiation device 270 and a control module 272. The energetic housing 268 defines an energetic recess 274 and a control recess 276. The energetic initiation device 270 and the control module 272 are disposed in the energetic recess 274 and the control recess 276, respectively. The removable energetic module 262 includes a cartridge plug interface 278. The cartridge plug interface 278 is configured to be received within the energetic module receptacle 266 of the cartridge plug 264. In some embodiments, the cartridge plug interface 278 may include threaded or keyed features, sealing elements, or retaining components configured to interface with respective elements defined by the energetic module receptacle 266. The removable energetic module 262 is in electrical communication with the upper wireline via an electrical pathway through the spring contact connecting pin 132, the connecting rod 130, and the spring contact activation pin 180.

[0030] The energetic initiation device 270 may include an ignitor and a booster charge housed within the energetic initiation device 270. The ignitor and the booster may be disposed coaxially within the energetic initiation device 270 or in a stacked or side-by-side orientation. In alternative embodiments, the energetic initiation device 270 may include other electrically activated initiators such as bridgewire ignitors, exploding foil initiators, or semiconductorbased initiators, optionally coupled the booster or one or more transfer charges. The activation of the energetic initiation device 270 may cause the release of off gas, which contacts the pistoncollar 168, moving the piston collar 168 from the first position to the second position, such that the first part 100 and second part 200 are releasable as discussed above.

[0031] The control module 272 may include an electronic firing circuit configured to deliver an initiation signal to the energetic initiation device 270. The control module 272 may incorporate one or more components such as a power conditioning circuit, capacitor discharge unit, logic controller, or safety interlock to regulate and control electrical energy supplied to the ignitor. The control module 272 may be electrically coupled to the energetic initiation device 270 through one or more conductive feedthroughs or connectors. In alternative embodiments, the control module 272 may include programmable or solid-state switching elements configured to receive commands from a surface control system SCS or an onboard control system to initiate firing of the energetic initiation device 270.

[0032] A wireline toolstring 1000 for downhole operations according to one embodiment is also provided herein. The wireline toolstring 1000 is generally depicted in FIG. 14. The wireline toolstring 1000 includes an upper wireline portion UWP configured to transmit electrical signals from a surface control system SCS. The release tool 10 is connected to the upper wireline portion UWP. A lower downhole tool assembly LDTA is connected to the release tool 10.

[0033] The upper wireline portion UWP may include an electrical conductor cable, wireline head, and associated telemetry or power modules configured to transmit electrical control signals, data, and power from the surface control system SCS to the release tool 10. The upper wireline portion UWP provides both mechanical support for the toolstring and electrical communication for control and monitoring of the release tool 10 and any connected downhole instruments. In some embodiments, the upper wireline portion UWP may further include tension subs, weak points, or centralizers to facilitate safe deployment and retrieval of the toolstring 1000 within a wellbore.

[0034] The lower downhole tool assembly LDTA is mechanically coupled to the release tool 10 and may include any suitable downhole instrument, such as a logging tool, perforating gun, setting tool, or sampling device. The lower downhole tool assembly LDTA is configured to perform one or more downhole operations in response to signals transmitted through the upper wireline portion and the release tool 10. In some embodiments, the release tool 10 selectively disconnects the lower downhole tool assembly LDTA from the upper wirelineportion UWP upon actuation of the energetic initiation device 176.

[0035] A method of releasing a lower downhole tool assembly LDTA from a wireline toolstring 1000 using the release tool 10. The method includes the step of transmitting a firing signal from a surface control system SCS through the wireline toolstring 1000 to the release tool 10. The removable energetic module 262 disposed in the second part 200 of the release tool 10 is activated in response to the firing signal. The second part 200 is released from the first part 100 such that the lower downhole tool assembly LDTA separates from the wireline toolstring 1000.

[0036] In the transmitting step, an electrical firing signal is generated by the surface control system SCS and transmitted through the wireline toolstring 1000 forming part of the upper wireline portion UWP. The firing signal may be initiated manually by an operator or automatically by a programmed control sequence. The signal may include one or more voltage pulses, coded sequences, or digital commands recognized by the control module of the release tool 10. The electrical firing signal may be conditioned or regulated.

[0037] In the activating step, the control module 272 receives the firing signal and initiates operation of the energetic initiation device 270 within the removable energetic module 262. Upon receipt of the signal, the control module 272 discharges stored electrical energy into the ignitor portion of the energetic initiation device 270, which ignites the booster charge contained therein. The resulting ballistic or pyrotechnic output provides a localized pressure or mechanical impulse used to actuate a release mechanism (e.g., displacing the piston collar allowing for the radial expansion of the collet fingers). In some embodiments, the control module 272 may include safety or arming logic configured to verify signal validity before allowing initiation to occur.

[0038] In the releasing step, the output (e.g., off gas) from the energetic initiation device 270 acts on the piston collar 168 of the first coupling structure 160, driving the piston collar 168 from the first position to the second position. In the first position, the inner surface 170 of the piston collar 168 overlies the collet fingers 164, compressing them radially inward into engagement with the detent 214 of the neck 212 on the second part 200 to retain the lower downhole tool assembly LDTA. When the piston collar 168 is displaced to the second position by the energetic output (e.g. off gas), the collet fingers 164 are permitted to expand radially outward from the detent 214, thereby releasing the neck 212 from the collet fingers 164. Thismovement disengages the second part 200 from the first part 100, allowing the lower downhole tool assembly LDTA to separate from the wireline toolstring 10.

[0039] As used here, the terms “above” and “below”; “up” and “down”; “upper” and “lower”; “upwardly” and “downwardly”; and other like terms indicating relative positions above or below a given point or element are used in this description to more clearly describe some embodiments. However, when applied to equipment and methods for use in wells that are deviated or horizontal, such terms may refer to a left to right, right to left, or diagonal relationship as appropriate.

[0040] The above description is that of current embodiments of the invention. Various alterations and changes can be made without departing from the spirit and broader aspects of the invention as defined in the appended claims, which are to be interpreted in accordance with the principles of patent law including the doctrine of equivalents. Any reference to elements in the singular, for example, using the articles “a,” “an,” “the,” or “said,” is not to be construed as limiting the element to the singular.REFERENCE NUMERALSRelease tool 10First part 100Electrical contact assembly 110Body 112Gripping surfaces 114Top seal interface 116Bottom seal interface 118Grooves 120Gaskets 122Top threading 124Bottom threading 126Cavity 128Connecting rod 130Connecting pin 132Spring 134First coupling structure 160Sleeve 162Collet fingers 164Recess 166Piston collar 168Inner surface 170Seal groove 172Piston seal 174Coupling housing 176First stepped key way 178Spring contact activation pin 180Spring 182Second part 200Second coupling structure 210Neck 212Detent 214Shoulder 216Body 218Second stepped keyway 220Wrench flats 222Energetic cavity 224Threaded female potion 226Energetic assembly 260Removable energetic module 262Cartridge plug 264Energetic module receptacle 266Energetic housing 268Energetic initiation device 270Control module 272Energetic recess 274Control recess 276Cartridge plug interface 278Axis A toWireline toolstring 1000Upper Wireline portion UWPLower downhole tool assembly LDTASurface control system SCS

Claims

CLAIMS1. A release tool for a wireline toolstring, the release tool comprising: a first part configured for connection to an upper wireline portion, the first part comprising: an electrical contact assembly configured to receive a firing signal; and a first coupling structure; a second part configured for connection to a lower downhole tool assembly, the second part comprising: a second coupling structure configured to releasably couple with the first coupling structure; and an energetic assembly comprising a removable energetic module configured to be replaced independently of the second part.

2. The release tool of claim 1, wherein the first coupling structure comprises a sleeve with a plurality of axially slotted collet fingers circumferentially spaced about and defining a recess.

3. The release tool of claim 2, wherein the first coupling structure comprises a piston collar disposed coaxially around the collet fingers, the piston collar is slidable between a first position in which an inner surface of the piston collar overlies the collet fingers such that the collet fingers are radially compressed inward to a retaining position and a second position in which the inner surface of the piston collar is axially displaced from the collet fingers such that the collet fingers rest in a release position.

4. The release tool of claim 3, wherein the second coupling structure comprises a neck configured to be received within the recess of the first coupling structure.

5. The release tool of claim 4, wherein the neck defines a detent engageable by the collet fingers and the collet fingers are configured such that in the first position the piston collar compresses the collet fingers such that the collet fingers radially engage the detent of the neck and the first part and the second part are releasably retained.

6. The release tool of any one of claims 1-5, wherein the first coupling structure comprises a coupling housing defining a first stepped keyway and the second coupling structure defines a corresponding second stepped keyway configured to interface with the first stepped keyway when the first part and the second part are coupled.

7. The release tool of any one of claims 1-6, wherein the removable energetic module comprises an energetic housing defining an energetic recess and a control recess, the energetic recess housing an energetic initiation device and the control recess housing a control module.

8. The release tool of any one of claims 1-7, wherein the energetic initiation device comprises an ignitor and a booster charge disposed coaxially within the energetic initiation device.

9. The release tool of any one of claims 1-8, wherein the electrical contact assembly comprises a spring contact connecting pin configured to electrically connect to the upper wireline portion.

10. The release tool of any one of claims 1-9, wherein the first coupling portion comprises a spring contact activation pin configured to electrically connect to the energetic assembly.

11. The release tool of any one of claims 3-5, wherein the first part further comprises a piston seal disposed between the piston collar and the sleeve.

12. The release tool of any one of claims 1-11, wherein the electrical contact assembly is an externally threaded top sub configured for threaded connection to an upper wireline head.

13. The release tool of any one of claims 1-12, wherein the energetic assembly comprises a threaded cartridge plug configured to threadedly interface with a threaded female portion of the second part such that the removable energetic module is retained within the second part.

14. A wireline toolstring for downhole operations, the wireline toolstring comprising an upper wireline portion configured to transmit electrical signals from a surface control system; the release tool according to any one of claims 1-13 connected to the upper wireline portion; and a lower downhole tool assembly connected to the release tool.

15. A method of releasing a lower downhole tool assembly from a wireline toolstring using the release tool according to any one of claims 1-14, the method comprising:transmitting a firing signal from a surface control system through the wireline toolstring to the release tool; activating the removable energetic module disposed in the second part of the release tool in response to the firing signal; and releasing the second part from the first part such that the lower downhole tool assembly separates from the wireline toolstring.

Images