Slip fishing socket

Abstract

The utility model belongs to the technical field of well drilling and workover fishing equipment, and discloses a slip fishing socket. The slip fishing barrel comprises an outer barrel body and a fishing slip located in the outer barrel body, relative displacement is formed between outer spiral sawteeth of the fishing slip and corresponding teeth in the outer barrel body, a first top cutting face is formed at the tail of the outer spiral sawteeth of the fishing slip, and a second top cutting face is formed at the tail of the first top cutting face. And a second top cutting surface is formed at the root part of a tooth corresponding to the outer spiral sawteeth in the outer cylinder body. According to the slip fishing socket, fishes of different specifications and some severely-deformed fishes can be fished, meanwhile, the inventory of blue tiles and spiral tiles is reduced, the number of times of tripping is reduced, and therefore the working efficiency is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of well drilling and repairing salvage equipment, in particular to a slip salvage tube. Background Art

[0002] In the continuous development of oil and gas fields, fish fall refers to objects that fall downhole, especially drilling tools that are left in the well due to accidents. Fish fall will have an impact on subsequent operations, so it is very necessary to salvage the fish. At present, the tool for salvaging pipe fish generally adopts a slip salvage tube. The existing slip salvage tube mainly consists of an upper joint, a cylinder, a guide shoe, a milling shoe connected to the inner cylinder, and a salvage slip (including a blue shoe or a spiral shoe) located in the cylinder. After the fish fall is trimmed by the milling shoe and caught by the salvage slip, the cylinder is lifted up, and the spiral serrated cone surface of the salvage slip and the corresponding tooth surface in the cylinder are relatively displaced, thereby clamping the fish and fishing it out.

[0003] However, in the salvage operation, the size of the fish is not very accurate because the fish will be worn during the work process. At the same time, the fish will be deformed to a certain extent after working in the well, resulting in uncertainty in the outer diameter and shape of the salvage part. Therefore, for some fish with large deformation, after the outer diameter is expanded to exceed the salvage range of the conventional slip salvage tube, the existing conventional slip salvage tube cannot meet the salvage needs. In addition, due to the structural and size limitations of the salvage slips, the salvage range span corresponding to each pair of salvage slips is very small, and since the salvage range of each pair of salvage slips is limited, a large number of blue tiles and screw tiles are generally prepared within the working range of the slip salvage tube. When it is necessary to salvage a fish whose size exceeds the salvage range of the conventional slips, it is necessary to pull the drill and replace the slips, so the work efficiency is limited. In addition, the structure of the salvage slips of the existing conventional slip overshot barrel makes the deformation of the salvage slips small, and the gap between the salvage slips and the barrel body is small, resulting in the conventional slip overshot barrel being unable to salvage fish with a large range of outer diameter changes, and the salvage slips will break due to stress concentration during long-term use, thereby increasing the cost of using the tool. In addition, the limit key of the milling shoe of the existing conventional slip overshot barrel is processed by welding, which has the risk of loose welding points and is more easily damaged during use. Utility Model Content

[0004] In view of the shortcomings of the prior art, the utility model proposes a slip overshot tube, which can salvage fallen fish of different specifications and some severely deformed fallen fish, while reducing the inventory of blue tiles and screw tiles, reducing the number of drilling times, thereby improving work efficiency.

[0005] According to the utility model, the slip salvage barrel comprises: an outer cylinder body and a salvage slip located in the outer cylinder body, wherein a relative displacement is formed between the outer spiral serrations of the salvage slip and the corresponding teeth in the outer cylinder body, wherein a first chamfered top surface is formed at the tail of the outer spiral serrations of the salvage slip, and a second chamfered top surface is formed at the root of the teeth in the outer cylinder body corresponding to the outer spiral serrations.

[0006] Furthermore, the first chamfered surface is parallel to the second chamfered surface.

[0007] Furthermore, a plurality of stress release grooves arranged at intervals along the circumferential direction are formed on the inner peripheral wall of the salvage slip.

[0008] Further, the stress relief groove extends along the entire axial length or a portion of the axial length of the fishing slip.

[0009] Furthermore, the cava salvage barrel also includes an upper joint threadedly connected to the upper end of the outer cylinder, the upper joint includes a joint body and a threaded connection section coaxially connected to the joint body, the outer cylinder is threadedly connected to the threaded connection section, and the end face of the upper end of the outer cylinder abuts against the end face of the joint body, wherein the plane structure at the abutment between the end face of the upper end of the outer cylinder and the end face of the joint body is an inclined surface.

[0010] Further, the salvaged slips are blue tiles or spiral tiles.

[0011] Furthermore, the slip salvage barrel further comprises a guide shoe threadedly connected to the lower end of the outer cylinder and a milling shoe connected between the outer cylinder and the guide shoe.

[0012] Furthermore, the milling shoe includes a milling shoe body, milling teeth formed on one side of the milling shoe body, and a limit key formed on the other side of the milling shoe body. A limit groove matching the limit key is formed on the inner wall of the outer cylinder, and the milling shoe body is limited between the limit groove and the end face of the guide shoe.

[0013] Furthermore, the milling shoe body and the limit key are integrally formed.

[0014] Furthermore, the slip overshot tube also includes a packing connected to the outer tube, and the salvage slip is located between the packing and the milling shoe.

[0015] The slip overshot tube of the utility model has a simple and reliable structure and is easy to process. Compared with conventional slip salvage, the slip overshot tube of the utility model has the following advantages:

[0016] 1) The salvage range of the blue tile / screw tile of the conventional slip overshot is generally ±1mm. The inner diameter of the conical surface of the outer cylinder of the slip overshot of the utility model is larger, the deformation of the blue tile / screw tile is larger, and the salvage range can be expanded to ±3mm, which can salvage some large-deformation fallen fish that cannot be salvaged by conventional slip overshot;

[0017] 2) The slip overshot of the utility model has few accessories. A set of tools only needs to be equipped with a few slips to cover the range of more than a dozen slips in the past, which can effectively reduce the inventory of blue tiles or screw tiles and reduce costs. At the same time, the slip overshot of the utility model can reduce the number of replacements of blue tiles or screw tiles and the number of trips, thereby effectively improving work efficiency.

[0018] 3) The outer cylinder of the slip overshot tube of the utility model and the conical root of the salvage slip are truncated to increase the cross-sectional area of ​​the stress-bearing part of the outer cylinder, thereby enhancing the strength of the outer cylinder and avoiding the stress concentration problem of the outer cylinder;

[0019] 4) The slip overshot of the utility model designs the end surface of the threaded connection between the outer cylinder and the upper joint into an inclined surface, which has a larger fitting area than the vertical surface of the conventional slip overshot and can store more elastic deformation potential energy, so the locking torque of the thread is larger, which can effectively avoid the problem of thread backlash; at the same time, a set screw is provided at the threaded connection between the outer cylinder and the upper joint, which can further effectively avoid the problem of thread backlash;

[0020] 5) The salvage slips of the slip overshot tube of the utility model are designed with stress release grooves inside, which makes the salvage slips more elastic, reduces the stress generated by the salvage slips during large deformation and the risk of breakage due to stress concentration during large deformation, thereby increasing the service life of the salvage slips and reducing the cost of using the tool;

[0021] 6) The limit key of the milling shoe of the slip overshot tube of the utility model is processed in an integrated manner, which has better strength than the conventional milling shoe and can withstand greater torque. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a cross-sectional schematic diagram of the structure of the slip overshot according to the first embodiment of the utility model;

[0023] Figure 2 It is a schematic diagram of the three-dimensional structure of the slip overshot according to the first embodiment of the utility model;

[0024] Figure 3 is a schematic cross-sectional view of the structure of a slip overshot according to a second embodiment of the utility model;

[0025] Figure 4 A schematic diagram of the working structure of a slip overshot according to a second embodiment of the utility model;

[0026] Figure 5 It is a schematic diagram of the matching structure of the outer spiral saw teeth of the salvage slip and the corresponding teeth in the outer cylinder in the utility model, wherein the structures of the first chamfered top surface and the second chamfered top surface are shown;

[0027] Figure 6 It is a schematic diagram of the matching structure of the outer spiral saw teeth of the salvage slip and the corresponding teeth in the outer cylinder in the prior art;

[0028] Figure 7 for Figure 1 The schematic diagram of the structure of the blue tile shown;

[0029] Figure 8 for Figure 3 The structural schematic diagram of the screw bush shown;

[0030] Fig. 9 for Figure 1 The structural schematic diagram of the outer cylinder shown;

[0031] Fig.10 for Fig. 9 An enlarged view of point A is shown;

[0032] Fig.11 for Fig. 9 An enlarged view of point B is shown;

[0033] Fig.12 It is an enlarged structural schematic diagram of the connection between the outer cylinder and the upper joint;

[0034] Fig.13 It is a structural schematic diagram of a set screw;

[0035] Fig.14 for Figure 1 The three-dimensional structural schematic diagram of the milling shoe is shown. DETAILED DESCRIPTION

[0036] In order to better understand the purpose, structure and function of the utility model, the utility model is further described in detail below in conjunction with the accompanying drawings.

[0037] Figures 1 to 3 FIG. 2 shows the structure of a slip overshot 100 according to an embodiment of the present invention. Figures 1 to 3 As shown, the slip overshot 100 may include: an outer cylinder 2 and a salvage slip 4 located in the outer cylinder 2, wherein the outer spiral serrations 40 of the salvage slip 4 and the corresponding teeth 20 in the outer cylinder 2 form a relative displacement. Figure 5 , Figure 7 as well as Figure 8 As shown, the tail of the outer spiral sawtooth 40 of the salvage slip 4 is formed with a first truncated top surface 401, combined with Figure 5 , Fig. 9 as well as Fig.10 As shown, a second chamfered surface 201 is formed at the root of the tooth 20 in the outer cylinder 2 corresponding to the outer spiral sawtooth 40 .

[0038] The slip overshot tube 100 of the utility model is combined with the Figure 4 As shown, salvage slip 4 (can be Figure 1 and Figure 7 The blue tile 41 shown is either Figure 2 or Figure 8 The screw shoe 42 shown in the figure bites the fallen fish 7. Since the outer spiral serrations 40 of the salvage slip 4 and the corresponding teeth 20 in the outer cylinder 2 form a relative displacement, when the outer cylinder 2 is lifted, the salvage slip 4 moves relatively downward in the outer cylinder 2. Since the teeth 50 of the outer cylinder 2 form a conical inclined surface inside, the salvage slip 4 will be locked under the pressure of the conical surface. At this time, the weight of the entire fallen fish is transferred to the outer cylinder 2 by the salvage slip 4. It should be noted that during the salvage operation, the salvage slip 4 can be specifically selected according to the outer diameter of the salvaged fish. When the outer diameter of the salvaged fish is small, the corresponding blue shoe 41 can be selected, and when the outer diameter of the salvaged fish is large, the corresponding screw shoe 42 can be selected.

[0039] like Figure 6 As shown in FIG. 1 , since the gap between the outer spiral serrations 40 of the salvage slip 4 of the conventional slip overshot barrel and the teeth 20 corresponding to the outer spiral serrations 40 in the outer barrel 2 is small, the deformation of the salvage slip 4 in the outer barrel 2 is small, resulting in a smaller outer diameter range of the salvage slip 4 for salvaging fallen fish; and as shown in FIG. Figure 5 As shown, the slip overshot tube 100 of the utility model embodiment forms a first chamfered surface 401 at the tail of the outer spiral serration 40 of the salvage slip 4, and forms a second chamfered surface 201 at the root of the tooth 20 corresponding to the outer spiral serration 40 in the outer cylinder 2, that is, the tail of the outer spiral serration 40 of the salvage slip 4 and the root of the tooth 20 corresponding to the outer spiral serration 40 in the outer cylinder 2 are chamfered at the same time. The chamfering increases the gap between the outer spiral serration 40 of the salvage slip 4 and the tooth 20 corresponding to the outer spiral serration 40 in the outer cylinder 2, so that the deformation of the salvage slip 4 in the outer cylinder 2 is greater, and thus the outer diameter range of the salvage slip 4 for salvaging fallen fish is also larger, so that when the slip overshot tube 100 of the utility model embodiment is used for salvage, fallen fish of different specifications and some severely deformed fallen fish can be salvaged, thereby greatly reducing the inventory of blue tiles and spiral tiles, reducing the number of drilling times, and effectively improving work efficiency.

[0040] In addition, combined Figure 5 and Figure 6As shown, the tail of the outer spiral serration 40 of the salvage slip 4 of the conventional slip overshot and the root of the tooth 20 corresponding to the outer spiral serration 40 in the outer cylinder 2 are not truncated, which will cause stress concentration in the outer cylinder 2 during downhole operation. Long-term downhole operation will cause fatigue fracture of the outer cylinder 2 due to stress concentration, causing tool damage. The slip overshot 100 of the embodiment of the utility model performs truncating treatment on the tail of the outer spiral serration 40 of the salvage slip 4 and the root of the tooth 20 corresponding to the outer spiral serration 40 in the outer cylinder 2, which increases the cross-sectional area of ​​the outer cylinder 2 at the stress-bearing position, increases the overall strength of the outer cylinder 2, and also avoids the stress concentration problem of the outer cylinder of the conventional slip overshot.

[0041] In such Figure 5 In the preferred embodiment shown, the first chamfered surface 401 and the second chamfered surface 201 may be parallel to further increase the gap between the outer spiral teeth 40 of the salvage slip 4 and the teeth 20 in the outer cylinder 2 corresponding to the outer spiral teeth 40 .

[0042] According to the utility model, in Figure 7 and Figure 8 In the preferred embodiment shown, a plurality of stress release grooves 402 arranged at intervals in the circumferential direction may be formed on the inner peripheral wall of the salvage slip 4. The provision of the stress release grooves 402 can make the blue tile 41 or the screw tile 42 more elastic, reduce the stress generated by the blue tile 41 or the screw tile 42 during large deformation, and reduce the risk of the blue tile 41 or the screw tile 42 being broken due to stress concentration during large deformation, which greatly increases the service life of the blue tile 41 or the screw tile 42 and reduces the cost of using the tool.

[0043] Preferably, the stress relief groove 402 may extend along the entire axial length or a portion of the axial length of the salvage slip 4. Figure 7 As shown, when the salvage slip 4 is a blue tile 41, the stress relief groove 402 can be formed at the open end of the blue tile 41, and the stress relief groove 402 extends along a part of the axial length of the salvage slip 4; Figure 8 As shown, when the salvage slip 4 is a screw washer 42 , the stress relief groove 402 can be formed in the entire length direction of the screw washer 42 . At this time, the stress relief groove 402 extends along the entire axial length of the salvage slip 4 .

[0044] According to the utility model, combined with Figure 1 , Figure 2 , Fig. 9 , Fig.11 as well as Fig.12As shown, the slip overshot tube 100 also includes an upper joint 1 threadedly connected to the upper end of the outer cylinder 2, and the upper joint 1 may include a joint body 11 and a threaded connection section 12 coaxially connected to the joint body 11, the outer cylinder 2 is threadedly connected to the threaded connection section 12, and the end face of the upper end of the outer cylinder 2 abuts against the end face of the joint body 11, wherein the plane structure of the abutment between the end face of the upper end of the outer cylinder 2 and the end face of the joint body 11 is an inclined surface 202. The setting of the inclined surface 202 makes the fitting area between the end face of the upper end of the outer cylinder 2 and the end face of the joint body 11 larger, and the elastic deformation potential energy that can be stored is also larger. Compared with the plane where the end face of the upper end of the outer cylinder 2 abuts against the end face of the joint body 11 in the prior art is a vertical plane, the setting of the utility model can make the locking torque of the thread larger, and can effectively avoid the problem of thread backlash.

[0045] Preferably, if Fig.13 As shown, in order to further avoid the problem of undercutting of the thread, a set screw 203 may be further connected at the threaded connection between the threaded connection section 12 and the outer cylinder 2. Further preferably, the set screws 203 may be arranged at intervals along the circumference of the threaded connection. The advantage of such a design is that the thread can transfer part of the torque to the set screws 203 in a circle around it, and the presence of the set pin 203 increases the locking torque of the thread, which can further effectively avoid the problem of undercutting of the thread.

[0046] According to the utility model, in Figures 1 to 3 In the preferred embodiment shown, the slip overshot 100 further includes a guide shoe 6 threadedly connected to the lower end of the outer cylinder 2 and a milling shoe 5 connected between the inner part of the outer cylinder 2 and the guide shoe 6. Figure 4 As shown, when the cava overshot tube 100 is working, the fallen fish 7 can enter the cava overshot tube 100 through the guidance of the guide shoe 6, and the milling shoe 5 can trim the irregular fish top of the fallen fish 7 to facilitate subsequent salvage work, and at the same time, it can also prevent the irregular fallen fish 7 from damaging its structure when entering the blue tile 41 or the screw tile 42.

[0047] In such Fig.14 In the preferred embodiment shown, the milling shoe 5 may include a milling shoe body 51, a milling tooth 52 formed on one side of the milling shoe body 51, and a limit key 53 formed on the other side of the milling shoe body 51. A limit groove matching the limit key 53 is formed on the inner wall of the outer cylinder 2, and the milling shoe body 51 is limited between the limit groove and the end surface of the guide shoe 6. This setting is used to achieve the fixation of the milling shoe 5.

[0048] In a preferred embodiment, the milling shoe body 51 and the limit key 53 are integrally formed. Compared with the conventional welding processing method of the limit key of the milling shoe and the milling shoe body 51, the advantage of the integral processing in this embodiment is that the milling shoe can be stronger, not easily damaged during use, and can withstand greater torque.

[0049] According to the utility model, in Figures 1 to 3 In the preferred embodiment shown, the slip overshot 100 further includes a packing 3 connected to the outer cylinder 21, and the salvage slip 4 is located between the packing 3 and the milling shoe 5. The packing 3 is provided to seal the end surface of the threaded connection between the outer cylinder 2 and the upper joint 1, thereby helping to improve the connection strength and life of the outer cylinder 2 and the upper joint 1.

[0050] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in this application should have the common meanings understood by technicians in the field to which the utility model belongs.

[0051] In the description of the present application, it should be understood that the terms "length", "axial", "root", "tail", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0052] In addition, the terms "first", "second", etc. are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features.

[0053] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the utility model, rather than to limit it; although the utility model has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the above embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the utility model, and they should all be included in the scope of the claims and description of the utility model. In particular, as long as there is no structural conflict, the various technical features mentioned in each embodiment can be combined in any way. The utility model is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A slip overshot, characterized in that: include: An outer cylinder and a salvage slip located inside the outer cylinder, wherein a relative displacement is formed between the outer spiral serrations of the salvage slip and the corresponding teeth inside the outer cylinder, wherein a first chamfered surface is formed at the tail of the outer spiral serrations of the salvage slip, and a second chamfered surface is formed at the root of the teeth inside the outer cylinder corresponding to the outer spiral serrations.

2. The slip overshot according to claim 1, characterized in that: The first chamfered surface is parallel to the second chamfered surface.

3. The slip overshot according to claim 1 or 2, characterized in that: A plurality of stress release grooves arranged at intervals along the circumferential direction are formed on the inner peripheral wall of the salvage slip.

4. The slip overshot according to claim 3, characterized in that: The stress relief groove extends along the entire axial length or a portion of the axial length of the salvage slip.

5. The slip overshot according to claim 1 or 2, characterized in that: The slip salvage tube also includes an upper joint threadedly connected to the upper end of the outer cylinder, the upper joint includes a joint body and a threaded connection section coaxially connected to the joint body, the outer cylinder is threadedly connected to the threaded connection section, and the end face of the upper end of the outer cylinder abuts against the end face of the joint body, wherein the plane structure where the end face of the upper end of the outer cylinder abuts against the end face of the joint body is an inclined surface.

6. The slip overshot according to claim 1 or 2, characterized in that: The salvage slips are blue tiles or spiral tiles.

7. The slip overshot according to claim 1 or 2, characterized in that: The slip overshot tube also includes a guide shoe threadedly connected to the lower end of the outer cylinder and a milling shoe connected inside the outer cylinder and between the guide shoe.

8. The slip overshot according to claim 7, characterized in that: The milling shoe includes a milling shoe body, milling teeth formed on one side of the milling shoe body, and a limit key formed on the other side of the milling shoe body. A limit groove matching the limit key is formed on the inner wall of the outer cylinder, and the milling shoe body is limited between the limit groove and the end face of the guide shoe.

9. The slip overshot according to claim 8, characterized in that: The milling shoe body and the limit key are integrally formed.

10. The slip overshot according to claim 7, characterized in that: The slip overshot barrel further comprises a packing connected to the outer barrel, and the salvage slip is located between the packing and the milling shoe.

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