A fishing device for oilfield downhole operations

Abstract

This invention discloses an oilfield downhole fishing device, comprising: a sleeve with an open receiving cavity, wherein an object to be fished is adapted to be inserted into the receiving cavity through the opening, and a lateral thrust surface is formed on the inner wall of the receiving cavity; and a clamping mechanism movably disposed within the receiving cavity along the axial direction of the sleeve, the clamping mechanism including at least two clamping members for cooperating clamping; during the movement of the clamping mechanism along the axial direction of the sleeve, the clamping members respectively slide and engage with the lateral thrust surface, and can move closer or further apart under the action of the lateral thrust surface to contract or expand, thereby clamping or releasing the object to be fished. The oilfield downhole fishing device of this invention is used to fish for objects that have fallen into the well and improves the clamping effect on the fallen object, preventing it from falling during the upward lifting process.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of petroleum machinery, in particular to an oilfield downhole operation fishing device. BACKGROUND

[0002] During oilfield downhole operation, objects such as parts often fall into the oil pipe, which need to be taken out, otherwise it may cause blockage, and even cause safety accidents.

[0003] In the prior art, a fishing tool is usually used to take out these objects, however, the existing fishing barrel has poor clamping effect and is easy to fall during upward lifting. SUMMARY

[0004] The present application provides an oilfield downhole operation fishing device for fishing downhole objects and improving the clamping effect on the objects to avoid falling during upward lifting.

[0005] The present application provides an oilfield downhole operation fishing device, which comprises:

[0006] A sleeve is formed with a receiving cavity having an opening, the object to be fished is adapted to be inserted into the receiving cavity through the opening, and a lateral thrust surface is formed on the inner wall of the receiving cavity;

[0007] A clamping mechanism is movably arranged in the receiving cavity along the axis of the sleeve, and the clamping mechanism comprises at least two clamping pieces for cooperating clamping;

[0008] During the axial movement of the clamping mechanism along the sleeve, the clamping pieces are respectively in sliding cooperation with the lateral thrust surface and can approach or move away from each other under the action of the lateral thrust surface to contract or expand, thereby realizing clamping or releasing the object to be fished.

[0009] As an embodiment, the clamping mechanism comprises:

[0010] A mounting plate, one end of each of the clamping pieces is hinged to the mounting plate, and the other end of each of the clamping pieces extends obliquely outward toward the opening and is used for sliding cooperation with the lateral thrust surface;

[0011] An elastic reset piece corresponds to each of the clamping pieces and applies an action force tending to move outward along the radial direction of the sleeve to the clamping pieces.

[0012] As an embodiment, the mounting plate is coaxially arranged with the sleeve, and the connecting ends of the plurality of clamping pieces are arranged in a circumferential direction of the mounting plate.

[0013] The lateral thrust surface is an inclined surface arranged obliquely relative to the axis of the sleeve.

[0014] In one embodiment, a wedge-shaped block is provided on the inner wall of the receiving cavity, and the lateral thrust surface is defined by the inclined surface on the wedge-shaped block;

[0015] Multiple wedge-shaped blocks are arranged at intervals along the circumference of the sleeve on the inner wall of the receiving cavity, and are arranged one-to-one with the clamping members.

[0016] As one implementation, the inner wall of the clamping member is provided with an anti-slip structure.

[0017] In one embodiment, a clamping ring is provided around the outer periphery of the clamping mechanism. The clamping ring is configured to abut against the outer wall of the clamping member and simultaneously apply a force to at least two clamping members in a direction that tends to move closer to each other.

[0018] In one embodiment, the clamping ring is connected to the adjusting drive mechanism. The clamping ring can move axially along the sleeve under the drive of the adjusting drive mechanism to displace relative to the clamping mechanism, thereby adjusting the magnitude of the force exerted by the clamping ring on the clamping member.

[0019] As one implementation, the oilfield downhole fishing device further includes: a telescopic drive mechanism, which is connected to the clamping mechanism and is used to drive the clamping mechanism to move axially along the sleeve.

[0020] In one implementation, the opening is located at the distal end of the sleeve;

[0021] The distal end of the sleeve is provided with a guide shoe, which provides a guiding channel for the object to be retrieved, and the channel extends to the opening and communicates with the receiving cavity.

[0022] As one implementation method, the oilfield downhole fishing device also includes:

[0023] An extension rod is coaxially arranged with the sleeve and connected to the proximal end of the sleeve.

[0024] Compared with the prior art, the advantages of the present invention are as follows:

[0025] The operating principle of the oilfield downhole fishing device in this embodiment is basically as follows:

[0026] Install the sleeve on the far end of the extension rod, and insert the sleeve into the oil well by holding the handle on the extension rod; adjust the position of the sleeve so that the upper end of the object is inserted into the receiving groove through the guide shoe;

[0027] The first power unit is controlled to drive the first telescopic rod to move downward, thereby moving the mounting plate and the clamping parts on the mounting plate downward. The lower end of the clamping parts slides on the lateral thrust surface and moves closer to each other under the action of the lateral thrust surface, so as to retract and clamp the object in the receiving cavity. The anti-slip teeth on the inner wall of the clamping parts can increase the friction force on the object.

[0028] The second power unit is operated to drive the second telescopic rod to move downward, and the clamping ring moves downward. The side pressure surface on the clamping ring can press against the outer wall of the clamping member, so that the clamping member tightens inward, thereby improving the clamping effect of the clamping member on the falling object and preventing the pipe from falling off when personnel are retrieving it upward. The sleeve is lifted and removed while the clamping member is in the clamping state. Attached Figure Description

[0029] The invention will now be described in more detail with reference to embodiments and the accompanying drawings.

[0030] Figure 1 This is a schematic diagram of the internal structure of an oilfield downhole fishing and retrieval device;

[0031] Figure 2 This is a structural diagram of the mounting plate and hinge seat in the clamping mechanism;

[0032] Figure 3 This is a schematic diagram of the clamping ring structure;

[0033] Figure 4 This is a schematic diagram of the external structure of an oilfield downhole fishing and retrieval device;

[0034] Figure 5 yes Figure 4 Enlarged view of the local structure at point A in the middle.

[0035] Figure label:

[0036] 1. Sleeve; 11. Receiving cavity; 12. Opening; 13. Lateral thrust surface; 14. First connecting part;

[0037] 2. Clamping mechanism; 21. Clamping component; 22. Mounting plate; 221. Mounting groove; 23. Elastic reset component; 24. Hinge shaft;

[0038] 25. Hinge seat; 251. First limiting part; 252. Second limiting part; 253. Slot;

[0039] 3. Telescopic drive mechanism; 31. First power component; 32. First telescopic rod;

[0040] 4. Mounting bracket;

[0041] 5. Clamping ring; 51. Side pressure surface;

[0042] 6. Adjustment drive mechanism; 61. Second power component; 62. Second telescopic rod;

[0043] 7. Shoe guide; 71. Passageway; 72. Rounded corners;

[0044] 8. Extension rod; 81. Mounting hole; 82. Second connecting part; 83. Handle. Detailed Implementation

[0045] The invention will now be further described with reference to the accompanying drawings.

[0046] This invention provides an oilfield downhole fishing device, which includes a sleeve 1 and a clamping mechanism 2.

[0047] The sleeve 1 has a receiving cavity 11 with an opening 12, into which the object to be retrieved (also known as the fallen object) can be inserted. The sleeve 1 is cylindrical, and the opening 12 is located at the far end of the sleeve 1 along its axial direction.

[0048] The clamping mechanism 2 is movably disposed in the receiving cavity 11 along the axial direction of the sleeve 1. The clamping mechanism 2 includes at least two clamping members 21 for cooperating clamping. A lateral thrust surface 13 is formed on the inner wall of the receiving cavity 11. During the movement of the clamping mechanism 2 along the axial direction of the sleeve, the clamping members 21 slide and cooperate with the lateral thrust surface 13 respectively, and can move closer or further away from each other under the action of the lateral thrust surface 13 to contract or expand, thereby clamping or releasing the falling object.

[0049] During the retrieval process, when the opening 12 on the sleeve 1 is aligned with the object, the sleeve 1 is pushed downwards, allowing the object to pass through the opening 12 and enter the receiving cavity 11. The clamping mechanism 2 moves forward along the axial direction of the sleeve 1, and the clamping members 21 slide on the lateral thrust surface 13 and move closer to each other under the action of the lateral thrust surface 13 to contract and clamp the object located in the receiving cavity 11. The sleeve 1 is lifted and removed while the clamping members 21 are in the clamping state. Then, the clamping mechanism 2 moves in the opposite direction along the axial direction of the sleeve 1, and the clamping members 21 move away from each other to expand and release the object to be retrieved. By adjusting the axial displacement of the clamping mechanism 2, the clamping force can be increased to prevent the object from falling during the lifting process.

[0050] It should be noted that the clamping mechanism 2 moves "positively" along the axial direction of the sleeve 1, corresponding to... Figure 1 The clamping mechanism 2 moves downward and closer to the opening 12; "reverse movement" corresponds to... Figure 1 The clamping mechanism 2 moves upward.

[0051] In one embodiment, the clamping mechanism 2 also includes a mounting plate 22 and an elastic reset member 23.

[0052] Mounting plate 22 is coaxially arranged with sleeve 1. The connecting ends of multiple clamping members 21 are arranged at intervals along the circumference of mounting plate 22 and hinged to mounting plate 22. The other end of each clamping member 21 extends obliquely outward toward opening 12 and is used to slide with lateral thrust surface 13.

[0053] Specifically, such as Figure 1 and 2 As shown, the mounting plate 22 is a circular plate. Multiple mounting grooves 221 are arranged circumferentially on the bottom wall of the mounting plate 22. A hinge shaft 24 extending along the normal direction at that location is fixedly installed in the mounting groove 221. A hinge seat 25 is rotatably mounted on the hinge shaft 24.

[0054] The hinge base 25 is provided with a slot 253. The connecting end of the clamp 21 is inserted into the slot 253 and is press-fitted with the inner wall of the slot 253, thereby fixing the clamp 21 on the hinge base 25.

[0055] The hinge seat 25 has a hinge hole that is coaxial with and rotatably fitted to the hinge shaft 24. The hinge seat 25 can rotate around the axis of the hinge shaft 24, thereby realizing the hinge between the connecting end on the clamping member 21 and the mounting plate 22.

[0056] In one embodiment, the mounting groove 221 is formed on the bottom edge of the mounting plate 22, and the mounting groove 221 is defined by a top wall, an inner sidewall connected to each edge of the top wall, and two opposite sidewalls. The two ends of the hinge shaft 24 are respectively connected to the two opposite sidewalls.

[0057] The hinge seat 25 is provided with a first limiting part 251 and a second limiting part 252. During the rotation of the hinge seat 25 around the hinge shaft 24, the first limiting part 251 and the second limiting part 252 can be used to stop and limit the hinge seat 25 and the clamping member 21 on the inner side wall or top wall of the mounting groove 221, so as to limit the rotation angle of the hinge seat 25 and the clamping member 21 within the preset rotation angle range, thereby improving the stability and reliability of the device.

[0058] Specifically, when the hinge seat 25 rotates around the hinge axis 24 in the first direction to the first preset position, the first limiting part 251 on the hinge seat 25 can stop and limit the inner side wall of the mounting groove 221 to restrict the hinge seat 25 from continuing to rotate in the first direction; when the hinge seat 25 rotates around the hinge axis 24 in the second direction opposite to the first direction and rotates to the second preset position, the second limiting part 252 on the hinge seat 25 can stop and limit the top wall of the mounting groove 221 to restrict the hinge seat 25 from continuing to rotate in the second direction, thereby limiting the rotation angle of the hinge seat 25 and the clamping member 21 within the preset rotation angle range.

[0059] like Figure 1As shown, the elastic reset member 23 corresponds one-to-one with the clamping member 21, and applies a force to the clamping member 21 that tends to be radially outward along the sleeve 1. The elastic reset member 23 can be a compression spring, with one end of each compression spring close to the center of the mounting plate 22 and connected to the bottom wall of the mounting plate 22, and the other end of each spring abutting against the inner wall of the clamping member 21.

[0060] In this embodiment, the clamping member 21 can rotate around the hinge shaft 24 on the connecting end to clamp or release the falling object; the elastic reset member 23 can apply force to the clamping member 21 under its own elastic force, and the clamping members 21 can move away from each other under the action of the elastic reset member 23 to reset and maintain in an outwardly expanding state.

[0061] As one implementation method, such as Figure 1 As shown, the lateral thrust surface 13 is an inclined surface that is set at an angle relative to the axis of the sleeve 1. From the near end to the far end, the distance from each point on the lateral thrust surface 13 to the axis of the sleeve 1 decreases.

[0062] A wedge-shaped block is provided on the inner wall of the receiving cavity 11, and the lateral thrust surface 13 is defined by the inclined surface on the wedge-shaped block; multiple wedge-shaped blocks are arranged at intervals along the circumference of the sleeve 1 on the inner wall of the receiving cavity 11, and are arranged one-to-one with the clamping member 21.

[0063] In one embodiment, the clamping member 21 is a slip plate, and the inner wall of the slip plate is provided with an anti-slip structure. The anti-slip structure can be anti-slip teeth. When multiple slip plates cooperate to clamp the object inserted into the cavity 11 of the sleeve 1, the anti-slip teeth increase the friction, which can prevent the object from falling when the sleeve 1 lifts the object upward.

[0064] In one implementation, there can be four slip plates, with two slip plates facing each other in the left-right direction and the other two slip plates facing each other in the front-back direction, and the anti-slip teeth are located on the inner wall of opposite sides of the slip plates.

[0065] As one implementation method, such as Figure 1 As shown, the clamping mechanism 2 is connected to a telescopic drive mechanism 3, which is used to drive the clamping mechanism 2 to move along the axial direction of the sleeve 1.

[0066] The sleeve 1 is provided with a mounting base 4, and the telescopic drive mechanism 3 includes a first power component 31 fixed on the mounting base 4 and a first telescopic rod 32 that is pulsatorically connected to the first power component 31; one end of the first telescopic rod 32 away from the first power component 31 passes through the mounting base 4 and is fixedly connected to the clamping mechanism 2.

[0067] In this embodiment, a telescopic drive mechanism 3 is provided to drive the clamping mechanism 2 to move axially along the sleeve 1. Compared with the rotary screw drive method, the axial drive telescopic method in this embodiment can avoid the problem that the difficulty of screw rotation and the required torque will increase with the increase of salvage depth.

[0068] The first power component 31 can be a drive cylinder or a drive hydraulic cylinder.

[0069] The mounting base 4 has a plate-like structure and divides the receiving cavity 11 into two independent chambers. The first chamber is connected to the opening 12 and the clamping mechanism 2 is located in the first chamber. The first power component 31 is located in the second chamber.

[0070] With this configuration, the mounting base 4 can both install and support the first power component 31 and seal the second chamber. During the retrieval process, it can prevent the liquid in the well from entering the second chamber through the first chamber, thereby preventing the first power component 31 from being soaked.

[0071] As one implementation method, such as Figure 1 and Figure 3 As shown, a clamping ring 5 is sleeved on the outer periphery of the clamping mechanism 2. The clamping ring 5 is configured to abut against the outer wall of the clamping member 21 and simultaneously apply a force to at least two clamping members 21 in a direction that tends to move closer to each other.

[0072] The clamping ring 5 is coaxially arranged with the mounting base 4 to ensure that the clamping ring 5 applies force to at least two clamping parts 21 at the same time.

[0073] like Figure 3 As shown, the inner wall of the clamping ring 5 has a side pressure surface 51 that can abut against the outer wall of the clamping member 21 and slide in cooperation with the outer wall of the clamping member 21. When the clamping ring 5 moves downward relative to the clamping member 21, the side pressure surface 51 on the clamping ring 5 can press down on the clamping member 21, causing the clamping members 21 to move closer together and retract inward, thereby increasing the clamping force of the clamping member 21 on the falling object and improving the clamping effect on the falling object to prevent it from falling during the lifting process; similarly, when the clamping ring 5 moves upward relative to the clamping member 21, the side pressure surface 51 on the clamping ring 5 can release the clamping member 21.

[0074] A tapered groove is provided on the inner wall of the clamping ring 5 along the circumferential direction. The side pressure surface 51 is defined by the side wall of the tapered groove. The inner diameter of the tapered groove gradually increases from top to bottom.

[0075] The clamping ring 5 is connected to the adjusting drive mechanism 6. The clamping ring 5 can move axially along the sleeve 1 under the drive of the adjusting drive mechanism 6 to displace relative to the clamping mechanism 2, thereby adjusting the magnitude of the force exerted by the clamping ring 5 on the clamping member 21.

[0076] The adjustment drive mechanism 6 includes a second power component 61 fixed on the mounting base 4 and a second telescopic rod 62 that is pulsatorically connected to the second power component 61; one end of the second telescopic rod 62 away from the second power component 61 passes through the mounting base 4 and is fixedly connected to the clamping ring 5.

[0077] The second power unit 61 can be a cylinder or a hydraulic cylinder.

[0078] At least two adjustment drive mechanisms 6 are provided, and the output ends of at least two adjustment drive mechanisms 6 are connected to the clamping ring 5 in a circumferentially spaced manner.

[0079] As one implementation method, such as Figure 1 As shown, the distal end of the sleeve 1 is provided with a guide shoe 7, which provides a guiding channel 71 for the object to be retrieved. The channel 71 extends to the opening 12 and communicates with the receiving cavity 11.

[0080] The channel 71 on the guide shoe 7 guides and directs the falling object, preventing it from failing to be inserted into the sleeve 1 due to incorrect position.

[0081] The far end of the guide shoe 7 is provided with a rounded corner 72, which makes it easier for the object to be inserted into the guide shoe 7 and the sleeve 1.

[0082] As one implementation method, such as Figure 1 and Figure 4 As shown, an extension rod 8 is also connected to the near end of the sleeve 1, and the extension rod 8 is coaxially arranged with the sleeve 1.

[0083] The extension rod 8 is threadedly connected to the sleeve 1. The distal end of the extension rod 8 is provided with a mounting hole 81, and the inner wall of the mounting hole 81 is provided with an internal thread. The proximal end of the sleeve 1 is provided with an external thread, and the proximal end of the sleeve 1 extends into the mounting hole 81. The external thread on the sleeve 1 is connected to the internal thread on the extension rod 8.

[0084] like Figure 4 and Figure 5 As shown, a first connecting portion 14 is formed on the outer peripheral wall of the sleeve 1 near its own end, and a first threaded hole is provided on the first connecting portion 14. A second connecting portion 82 is correspondingly formed on the outer peripheral wall of the extension rod 8, and a second threaded hole is provided on the second connecting portion 82.

[0085] When the sleeve 1 is threadedly connected to the extension rod 8, the first connecting part 14 and the second connecting part 82 are opposite each other, and the first threaded hole and the second threaded hole are aligned. The threaded connectors are connected to the first connecting part 14 and the second connecting part 82 in sequence, thereby improving the stability and reliability of the connection between the extension rod 8 and the sleeve 1.

[0086] like Figure 4 As shown, a handle 83 is provided at the near end of the extension rod 8 for gripping.

[0087] The operating principle of the oilfield downhole fishing device in this embodiment is basically as follows:

[0088] Install the sleeve 1 on the far end of the extension rod 8, and insert the sleeve 1 into the oil well by holding the handle 83 on the extension rod 8; adjust the position of the sleeve 1 so that the upper end of the object is inserted into the receiving groove through the guide shoe 7;

[0089] The first power unit 31 is controlled to drive the first telescopic rod 32 to move downward, thereby driving the mounting plate 22 and the clamping member 21 on the mounting plate 22 to move downward. The lower end of the clamping member 21 slides on the lateral thrust surface 13 and moves closer to each other under the action of the lateral thrust surface 13, so as to retract and clamp the object falling in the receiving cavity 11. The anti-slip teeth on the inner wall of the clamping member 21 can increase the friction force on the object falling.

[0090] The second power unit 61 is operated to drive the second telescopic rod 62 to move downward, and drive the clamping ring 5 to move downward. The side pressure surface 51 on the clamping ring 5 can press against the outer wall of the clamping member 21, so that the clamping member 21 is tightened inward, thereby improving the clamping effect of the clamping member 21 on the falling object and preventing the object from falling off when personnel are retrieving the falling pipe upward. When the clamping member 21 is in the clamping state, it is lifted up and the sleeve 1 is taken out.

[0091] Although the invention has been described with reference to preferred embodiments, various modifications can be made and components can be replaced with equivalents without departing from the scope of the invention. In particular, the technical features mentioned in the various embodiments can be combined in any manner as long as there is no structural conflict. The invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A fishing device for oilfield downhole operations, characterized in that, include: A sleeve having an open receiving cavity, the object to be retrieved being inserted into the receiving cavity through the opening, and a lateral thrust surface being formed on the inner wall of the receiving cavity; A clamping mechanism is movably disposed within the receiving cavity along the axial direction of the sleeve, the clamping mechanism comprising at least two clamping members for cooperating clamping; During the movement of the clamping mechanism along the sleeve axis, the clamping members slide and engage with the lateral thrust surfaces respectively, and can move closer or further apart to contract or expand under the action of the lateral thrust surfaces, thereby clamping or releasing the object to be retrieved.

2. The oilfield downhole fishing and retrieval device according to claim 1, characterized in that, The clamping mechanism includes: Mounting plate, one end of each clamping member is hinged to the mounting plate, and the other end of each clamping member extends obliquely outward toward the opening and is used to slide in cooperation with the lateral thrust surface; The elastic reset member corresponds to each of the clamping members and applies a force to the clamping members that tends to be radially outward along the sleeve.

3. The oilfield downhole fishing and retrieval device according to claim 2, characterized in that, The mounting plate is coaxially arranged with the sleeve, and the connecting ends on the multiple clamping members are arranged at intervals along the circumference of the mounting plate; The lateral thrust surface is an inclined surface that is tilted relative to the axis of the sleeve.

4. The oilfield downhole fishing and retrieval device according to any one of claims 1-3, characterized in that, A wedge-shaped block is provided on the inner wall of the receiving cavity, and the lateral thrust surface is defined by the inclined surface on the wedge-shaped block; Multiple wedge-shaped blocks are arranged at intervals along the circumference of the sleeve on the inner wall of the receiving cavity, and are arranged one-to-one with the clamping members.

5. The oilfield downhole fishing and retrieval device according to claim 1, characterized in that, The inner wall of the clamping member is provided with an anti-slip structure.

6. The oilfield downhole fishing and retrieval device according to any one of claims 1-3, characterized in that, The clamping mechanism is fitted with a clamping ring on its outer periphery. The clamping ring is configured to abut against the outer wall of the clamping member and simultaneously apply a force to at least two clamping members in a direction that tends to move them closer to each other.

7. The oilfield downhole fishing and retrieval device according to claim 6, characterized in that, The clamping ring is connected to the adjusting drive mechanism. The clamping ring can move along the axial direction of the sleeve under the drive of the adjusting drive mechanism to displace relative to the clamping mechanism, thereby adjusting the magnitude of the force exerted by the clamping ring on the clamping member.

8. The oilfield downhole fishing and retrieval device according to claim 1, characterized in that, Also includes: A telescopic drive mechanism is connected to the clamping mechanism and is used to drive the clamping mechanism to move axially along the sleeve.

9. The oilfield downhole fishing and retrieval device according to claim 1, characterized in that, The opening is located at the distal end of the sleeve; The distal end of the sleeve is provided with a guide shoe, which provides a guiding channel for the object to be retrieved, and the channel extends to the opening and communicates with the receiving cavity.

10. The oilfield downhole fishing and retrieval device according to claim 1, characterized in that, Also includes: An extension rod is coaxially arranged with the sleeve and connected to the proximal end of the sleeve.

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