Forward and reverse circulation fishing device

Abstract

The utility model discloses a forward and reverse circulation salvage device which solves the technical problems that a salvage device is difficult to achieve forward and reverse circulation salvage, and the salvage efficiency and the salvage success rate are low. The device comprises an upper connector, a circulating short section, a salvage short section and a lower connector, the salvage short section comprises a salvage outer pipe and a salvage inner pipe, a salvage annular cavity is formed between the salvage outer pipe and the salvage inner pipe, the salvage inner pipe comprises a filter screen pipe, a plugging pressing cap, a slotted oil pipe, a conversion pipe and a plugging seat, and the filter screen pipe is detachably connected with the plugging pressing cap. The conversion pipe is connected with the slotted oil pipe, the plugging seat is detachably connected with the conversion pipe, after the plugging pressing cap and the plugging seat are detached, the filter sieve pipe can be directly connected with the conversion pipe, and the circulating short section is used for controlling the flowing direction of flushing fluid and enabling the flushing fluid to perform positive circulation and reverse circulation. According to the utility model, large-range forward and reverse circulation salvage can be realized, the salvage efficiency and the salvage success rate are improved, the operation cost is reduced, and the risk of drill jamming accidents can be reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of fishing devices, and particularly relates to a positive and negative circulation fishing device. Background Art

[0002] The development of offshore oil and gas resources is a hot spot and key point in the current development of the world's marine economy. Offshore oil and gas resources not only have large reserves, but modern science and technology already have great capabilities for their development. The offshore oil and gas industry has developed into a new and high-output leading industry in the marine economy. At present, during the production process of oil wells, fishing devices are usually required to fish for downhole objects to ensure the normal production of oil wells.

[0003] The fishing devices in the related art usually adopt circulating fishing devices, which mainly consist of an upper joint, a lower joint, an outer barrel, and an internal screen pipe. The fishing devices in the related art have the following problems:

[0004] (1) The mud can only flow unidirectionally or the fishing device can only perform local positive and negative circulation, with limited fishing ability and low fishing efficiency;

[0005] (2) The fishing cavity volume of the fishing device is relatively small, the fishing cycle of downhole objects is long, and the operation cost is high;

[0006] (3) During the fishing process, debris is easily returned upward between the fishing drill tool and the annulus of the casing, causing a stuck drill accident. Summary of the Utility Model

[0007] In order to solve all or part of the above problems, the purpose of the utility model is to provide a positive and negative circulation fishing device, which can realize a large-range positive and negative circulation of the washing fluid, improve the fishing efficiency and fishing success rate, reduce the operation cost, and also reduce the risk of stuck drill accidents.

[0008] The utility model provides a positive and negative circulation fishing device, which includes an upper joint, a circulation short section, a fishing short section, and a lower joint that are connected in sequence from top to bottom. The fishing short section includes a fishing outer pipe and a fishing inner pipe. The fishing inner pipe is coaxially arranged inside the fishing outer pipe, and a fishing annulus is formed between the fishing outer pipe and the fishing inner pipe;

[0009] The fishing inner pipe includes:

[0010] A filter screen pipe, the top of which is detachably connected to the circulation short section;

[0011] A plugging compression cap, which is detachably connected to the bottom of the filter screen pipe;

[0012] A slotted tubing, the bottom of which is connected to the lower joint;

[0013] A conversion pipe, which is arranged at the top of the slotted tubing;

[0014] The plugging seat is detachably connected to the top of the conversion pipe;

[0015] The fishing holes are multiple in number and are respectively arranged through the plugging seat. The multiple fishing holes respectively communicate the inside of the plugging seat with the fishing annulus cavity;

[0016] Wherein, the top of the fishing outer pipe is detachably connected to the circulation nipple, and the bottom is detachably connected to the lower sub. After the plugging cap and the plugging seat are respectively disassembled, the bottom of the filter screen pipe can be directly connected to the conversion pipe to realize the communication between the filter screen pipe and the slotted tubing;

[0017] The circulation nipple is used to control the flow direction of the well flushing fluid, so that the well flushing fluid flows through the upper sub, the circulation nipple, the filter screen pipe, the conversion pipe, the slotted tubing and the lower sub in sequence, and returns to the wellhead through the wellbore annulus to realize positive circulation fishing;

[0018] Or make the well flushing fluid flow through the upper sub, the circulation nipple, the wellbore annulus, the lower sub, the slotted tubing, the conversion pipe, the plugging seat, the fishing holes, the fishing annulus and the filter screen pipe in sequence, then enter the wellbore annulus through the circulation nipple and return to the wellhead to realize reverse circulation fishing.

[0019] Optionally, the circulation nipple includes:

[0020] The circulation outer pipe is connected to the upper sub at the top;

[0021] The conversion joint is connected to the circulation outer pipe at the top and to the fishing outer pipe at the bottom;

[0022] The circulation inner pipe is coaxially arranged inside the circulation outer pipe and is connected to the conversion joint at the bottom. A circulation cavity is formed between the circulation inner pipe and the circulation outer pipe;

[0023] The sealing ball seat is connected to the top of the circulation inner pipe, and after the external steel ball is thrown, it can block the sealing ball seat;

[0024] The first circulation holes are multiple in number and are respectively arranged through the conversion joint. The multiple first circulation holes are respectively communicated with the circulation cavity, and a first oil plug is detachably connected to each first circulation hole;

[0025] The support lining blocks are multiple in number and are respectively arranged on the circulation inner pipe. The multiple support lining blocks respectively pass through the circulation outer pipe;

[0026] The second circulation holes are provided in multiple groups and penetrate through the support lining blocks respectively. The second circulation holes penetrate through the circulation inner pipe, and the second circulation holes connect the inside of the circulation inner pipe with the wellbore annulus. A second oil plug is detachably connected in each of the second circulation holes.

[0027] Optionally, the first circulation holes are arranged to incline downward, and the second circulation holes are arranged to incline upward.

[0028] Optionally, a plurality of relief holes are provided through the outer circulation pipe, and the plurality of support lining blocks respectively pass through the corresponding relief holes, and the support lining blocks are detachably connected to the circulation inner pipe.

[0029] Optionally, a plurality of limiting grooves are provided on the outer side wall of the circulation inner pipe, and the plurality of support lining blocks are respectively tightly clamped into the corresponding limiting grooves.

[0030] Optionally, a setting valve cup for setting an external steel ball is provided at the bottom of the upper joint.

[0031] Optionally, the plugging cap is sleeved on the bottom of the filter screen pipe and is threadedly connected to the filter screen pipe. The bottom of the plugging seat is inserted into the conversion pipe and is threadedly connected to the conversion pipe, and the external thread at the bottom of the filter screen pipe matches the internal thread at the top of the conversion pipe.

[0032] Optionally, a guiding conical surface is provided at the bottom of the plugging cap and the top of the plugging seat respectively.

[0033] Optionally, the outer side wall of the plugging cap is in close fit with the inner side wall of the fishing outer pipe, and a plurality of communication channels are provided on the outer side wall of the plugging cap, and the well flushing fluid can flow through the communication channels.

[0034] Optionally, a plurality of support ribs are provided on the outer side wall of the plugging seat, and the plurality of support ribs are respectively in close contact with the inner side wall of the fishing outer pipe, and the well flushing fluid can flow through the gaps between adjacent two support ribs.

[0035] It can be seen from the above technical solutions that the positive and negative circulation fishing device provided by the present utility model has the following advantages:

[0036] The device can achieve large - range positive and reverse circulation of the well - washing fluid, improve the fishing efficiency and success rate, reduce the operation cost, and also reduce the risk of sticking accidents. At the same time, the fishing device is provided with a fishing ring cavity, so that debris can be collected in the fishing ring cavity to prevent the debris from flowing back to the bottom of the well. The fishing ring cavity can also collect as much debris as possible, improve the utilization efficiency of the fishing device, and reduce the operation cost. Moreover, the filter screen pipe adopts a replaceable design, and filter screen pipes with different filtration precisions can be replaced according to different requirements to meet a variety of different precision requirements and improve the use adaptability.

[0037] Other features and advantages of the present utility model will be described in the subsequent specification. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The drawings are used to provide a further understanding of the technical solution of the present utility model, and constitute a part of the specification. Together with the embodiments of the present utility model, they are used to explain the technical solution of the present utility model, and do not constitute a limitation to the technical solution of the present utility model.

[0039] Figure 1 is an exploded view of the fishing device in the embodiment of the present utility model;

[0040] Figure 2 is an exploded view of the circulation sub in the embodiment of the present utility model;

[0041] Figure 3 is a cross - sectional view of the circulation sub in the embodiment of the present utility model;

[0042] Figure 4 is a cross - sectional view of the fishing sub in the embodiment of the present utility model;

[0043] Figure 5 is a schematic structural diagram of the filter screen pipe and the plugging cap in the embodiment of the present utility model;

[0044] Figure 6 is a schematic structural diagram of the plugging seat and the conversion pipe in the embodiment of the present utility model;

[0045] Figure 7 is a schematic diagram of the use state when the fishing device in the embodiment of the present utility model performs positive - circulation fishing operation;

[0046] Figure 8 is a schematic diagram of the use state when the fishing device in the embodiment of the present utility model performs reverse - circulation fishing operation.

[0047] Description of the reference numerals:

[0048] 1. Upper joint; 2. Circulation sub; 201. Circulation outer pipe; 202. Adapter; 203. Circulation inner pipe; 204. Circulation cavity; 205. Sealing ball seat; 206. First circulation hole; 207. First oil plug; 208. Support lining block; 209. Relief hole; 210. Second circulation hole; 211. Second oil plug; 212. Limit groove; 3. Fishing sub; 31. Fishing outer pipe; 32. Fishing inner pipe; 321. Filter screen pipe; 322. Sealing cap; 323. Sealing seat; 324. Adapter pipe; 325. Slotted tubing; 326. Fishing hole; 327. Guide conical surface; 328. Connecting flow channel; 329. Support rib; 33. Fishing ring cavity; 4. Lower joint; 5. Setting valve cup. Detailed implementation manners

[0049] To make the objectives, technical solutions and advantages of the present utility model clearer and more understandable, the embodiments of the present utility model will be described in detail below with reference to the accompanying drawings. It should be noted that, without conflict, the embodiments in the present utility model and the features in the embodiments may be arbitrarily combined with each other.

[0050] As Figures 1 - 8 shown in the embodiment of the present utility model, a positive and negative circulation fishing device is disclosed in this embodiment, which includes an upper joint 1, a circulation sub 2, a fishing sub 3 and a lower joint 4 connected in sequence from top to bottom. The circulation sub 2 includes a circulation outer pipe 201, an adapter 202 and a circulation inner pipe 203. The top of the circulation outer pipe 201 is threadedly connected to the upper joint 1, the top of the adapter 202 is threadedly connected to the circulation outer pipe 201, and the bottom is connected to the fishing sub 3. The circulation inner pipe 203 is coaxially arranged inside the circulation outer pipe 201 and the bottom is threadedly connected to the adapter 202. At the same time, a circulation cavity 204 is formed between the circulation inner pipe 203 and the circulation outer pipe 201.

[0051] In one embodiment, as Figure 1 , Figure 2 , Figure 3 shown, a sealing ball seat 205 is threadedly connected to the top of the circulation inner pipe 203. After an external steel ball is dropped, it can block the sealing ball seat 205 to force the washing fluid to change its flow path, that is, the washing fluid can flow through the circulation cavity 204.

[0052] In one embodiment, as Figure 2 , Figure 3 shown, a plurality of first circulation holes 206 are penetrated through the adapter 202. The plurality of first circulation holes 206 are equidistantly arranged along the circumferential direction of the adapter 202. The plurality of first circulation holes 206 are respectively communicated with the circulation cavity 204, and a first oil plug 207 is detachably connected to each first circulation hole 206.

[0053] In one embodiment, asFigure 2 , Figure 3 As shown in Figure 3 , a plurality of support liners 208 are provided on the outer side wall of the circulating inner pipe 203. The plurality of support liners 208 are arranged at equal intervals along the circumferential direction of the circulating inner pipe 203. A plurality of relief holes 209 are provided through the circulating outer pipe 201, and the plurality of support liners 208 respectively pass through the corresponding relief holes 209 and block the corresponding relief holes 209.

[0054] In one embodiment, as Figure 2 , Figure 3 shown, a plurality of groups of second circulation holes 210 are respectively provided through each support liner 208. The second circulation holes 210 penetrate through the circulating inner pipe 203, and the second circulation holes 210 communicate the inside of the circulating inner pipe 203 with the wellbore annulus. At the same time, a second oil plug 211 is detachably connected to each second circulation hole 210.

[0055] In one embodiment, as Figure 2 , Figure 3 shown, the support liner 208 is detachably connected to the circulating inner pipe 203 so that the support liner 208 can be taken out through the relief hole 209. A plurality of limit grooves 212 are provided on the outer side wall of the circulating inner pipe 203. One side of the plurality of support liners 208 is tightly engaged in the corresponding limit grooves 212, and the other side passes through the corresponding relief holes 209 to realize the fixation of the circulating outer pipe 201 and the circulating inner pipe 203.

[0056] In this embodiment, the support liner 208 is connected to the circulating inner pipe 203 by fastening screws. Of course, other fasteners or fixing methods can also be used. The first oil plug 207 is threadedly connected to the first circulation hole 206, and the second oil plug 211 is also threadedly connected to the second circulation hole 210. Of course, other detachable connection methods such as snap connection can also be used, and no more examples are listed here.

[0057] In one embodiment, as Figure 2 , Figure 3 shown, the first circulation hole 206 is inclined downward, and the second circulation hole 210 is inclined upward to improve the guiding effect on the washing fluid. A setting valve cup 5 is provided at the bottom of the upper joint 1, and the setting valve cup 5 is used to set an external steel ball to ensure the sealing effect.

[0058] In one embodiment, as Figure 1 , Figure 4As shown, the fishing sub 3 includes a fishing outer pipe 31 and a fishing inner pipe 32. The top of the fishing outer pipe 31 is sleeved on the circulating outer pipe 201 and is threadedly connected to the circulating outer pipe 201. The bottom of the fishing outer pipe 31 is sleeved on the lower joint 4 and is threadedly connected to the lower joint 4. The fishing inner pipe 32 is coaxially arranged inside the fishing outer pipe 31, and a fishing ring cavity 33 is formed between the fishing outer pipe 31 and the fishing inner pipe 32, and the fishing ring cavity 33 is used to collect debris.

[0059] In one embodiment, as Figure 4 、 Figure 5 、 Figure 6 shown, the fishing inner pipe 32 includes a filter screen pipe 321, a plugging cap 322, a plugging seat 323, a conversion pipe 324, and a slotted tubing 325 arranged in sequence from top to bottom. The top of the filter screen pipe 321 is inserted into the adapter 202 and is threadedly connected to the adapter 202. The plugging cap 322 is sleeved on the bottom of the filter screen pipe 321 and is threadedly connected to the filter screen pipe 321. The bottom of the plugging seat 323 is inserted into the conversion pipe 324 and is threadedly connected to the conversion pipe 324. The bottom of the slotted tubing 325 is inserted into the lower joint 4 and is threadedly connected to the lower joint 4.

[0060] In one embodiment, as Figure 1 、 Figure 4 shown, a plurality of fishing holes 326 are formed through the plugging seat 323. The plurality of fishing holes 326 are arranged at equal intervals along the circumferential direction of the plugging seat 323, and the plurality of fishing holes 326 respectively communicate the inside of the plugging seat 323 with the fishing ring cavity 33, so that the washing fluid and debris can enter the fishing ring cavity 33 through the fishing holes 326.

[0061] In one embodiment, as Figure 4 、 Figure 5 、 Figure 6 shown, the external thread at the bottom of the filter screen pipe 321 matches the internal thread at the top of the conversion pipe 324. When the plugging cap 322 and the plugging seat 323 are respectively disassembled, the bottom of the filter screen pipe 321 can be directly connected to the conversion pipe 324 to realize the connection between the filter screen pipe 321 and the slotted tubing 325, so as to prepare for the positive circulation fishing operation.

[0062] As Figure 7As shown in the figure, when performing a positive circulation fishing operation, the fishing outer pipe 31 is disassembled from the bottom of the circulation outer pipe 201, and the lower joint 4 is disassembled from the bottom of the fishing outer pipe 31. Then, the plugging compression cap 322 and the plugging seat 323 are disassembled respectively, and the bottom of the filter screen pipe 321 is connected to the conversion pipe 324. Subsequently, the lower joint 4 is installed at the bottom of the fishing outer pipe 31, and the fishing outer pipe 31 is installed at the bottom of the circulation outer pipe 201. At the same time, the first oil plug 207 and the second oil plug 211 are installed. Immediately afterwards, the fishing device is lowered into the wellbore through external equipment, and the washing fluid is pumped into the fishing device. At this time, the washing fluid sequentially passes through the upper joint 1, the sealing ball seat 205, the circulation inner pipe 203, the filter screen pipe 321, the conversion pipe 324, the slotted oil pipe 325, and the lower joint 4, and enters the wellbore annulus. Subsequently, the washing fluid returns to the wellhead through the wellbore annulus. During this process, the washing fluid carries debris back up, thereby realizing the positive circulation fishing operation.

[0063] As Figure 8 shown in the figure, when performing a reverse circulation fishing operation, the plugging compression cap 322 and the plugging seat 323 are installed respectively, and the first oil plug 207 and the second oil plug 211 are installed at the same time. Then, a steel ball is put into the circulation outer pipe 201, and the steel ball plugs the sealing ball seat 205. Immediately afterwards, the fishing device is lowered into the wellbore through external equipment, and the washing fluid is pumped into the fishing device. At this time, the washing fluid sequentially passes through the upper joint 1 and enters the circulation cavity 204, and enters the wellbore annulus through a plurality of first circulation holes 206. Then, the washing fluid carrying debris sequentially passes through the lower joint 4, the slotted oil pipe 325, the conversion pipe 324, and the plugging seat 323, and enters the fishing ring cavity 33 through the fishing hole 326. At this time, the debris is blocked by the filter screen pipe 321, and the debris is retained in the fishing ring cavity 33. The washing fluid enters the circulation inner pipe 203 through the filter screen pipe 321, and enters the wellbore annulus through the second circulation hole 210. Finally, the washing fluid returns to the wellhead through the wellbore annulus, thereby realizing the reverse circulation fishing operation.

[0064] In one embodiment, as Figure 1 、 Figure 4 shown in the figure, a guiding conical surface 327 is integrally formed at the bottom of the plugging compression cap 322 and the top of the plugging seat 323 respectively to improve the guiding effect and enable the washing fluid to flow smoothly.

[0065] In one embodiment, as Figure 1 、 Figure 4 shown in the figure, the outer side wall of the plugging compression cap 322 is in close fit with the inner side wall of the fishing outer pipe 31, and a plurality of communicating flow channels 328 are provided on the outer side wall of the plugging compression cap 322, and the washing fluid can flow through the communicating flow channels 328.

[0066] In one embodiment, as Figure 1 、 Figure 4As shown in the figure, a plurality of support ribs 329 are integrally formed on the outer side wall of the plugging seat 323. The plurality of support ribs 329 are arranged at equal intervals along the circumferential direction of the plugging seat 323, and the plurality of support ribs 329 are respectively in close contact with the inner side wall of the fishing outer pipe 31. The washing fluid can flow through the gaps between adjacent two support ribs 329.

[0067] Since the outer side wall of the plugging cap 322 is in close fit with the inner side wall of the fishing outer pipe 31, and the support ribs 329 on the plugging seat 323 are in close contact with the inner side wall of the fishing outer pipe 31, the support and limitation of the plugging cap 322 and the plugging seat 323 are realized, reducing the risk of the filter screen pipe 321 and the slotted oil pipe 325 shaking during the flow of the washing fluid, thereby reducing the risk of deformation or fracture of the filter screen pipe 321 and the slotted oil pipe 325.

[0068] As can be seen from the above, the adoption of this device has the following advantages:

[0069] (1) This fishing device can realize large-range positive and reverse circulation of the washing fluid, improving the fishing efficiency and success rate. At the same time, a fishing ring cavity 33 is arranged in the fishing device, effectively ensuring that debris is collected in the fishing ring cavity 33, avoiding the debris from flowing back to the bottom of the well again. The fishing ring cavity 33 can also collect as much debris as possible, improving the use efficiency of the tool and reducing the operation cost.

[0070] (2) The plugging cap 322 and the plugging seat 323 respectively adopt a detachable design. When the fishing device needs to carry out positive circulation fishing operation, only the plugging cap 322 and the plugging seat 323 need to be removed, and the filter screen pipe 321 and the conversion pipe 324 are connected, which is simple and fast to operate, improving the operation efficiency.

[0071] (3) The filter screen pipe 321 adopts a replaceable design, and filter screens with different filtration precisions can be replaced according to different requirements, meeting various different precision requirements and improving the use adaptability.

[0072] (4) Most of the components of this fishing device adopt a design of threaded connection or removable screws, which can easily realize the switching between positive circulation and reverse circulation. At the same time, this design can also realize the separate maintenance and replacement of each component after damage, improving the maintenance convenience and reducing the maintenance cost.

[0073] It should be noted that unless otherwise specified, the technical terms or scientific terms used in this utility model should be the common meanings understood by those skilled in the art to which this utility model belongs.

[0074] In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. In the description of this utility model, the meaning of "a plurality of" is more than two, unless otherwise clearly and specifically defined.

[0075] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present utility model and are not intended to limit them; although the present utility model has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present utility model, and they should all be covered by the scope of the claims and the description of the present utility model. In particular, as long as there is no structural conflict, the technical features mentioned in each embodiment can be combined in any way. The present utility model is not limited to the specific embodiments disclosed in the text, but includes all technical solutions falling within the scope of the claims.

Claims

1. A positive and negative circulation fishing device, characterized in that, It includes an upper joint (1), a circulating nipple (2), a fishing nipple (3), and a lower joint (4) connected in sequence from top to bottom. The fishing nipple (3) includes a fishing outer pipe (31) and a fishing inner pipe (32). The fishing inner pipe (32) is coaxially arranged inside the fishing outer pipe (31), and a fishing annular cavity (33) is formed between the fishing outer pipe (31) and the fishing inner pipe (32). The fishing inner pipe (32) includes: A filter screen pipe (321) detachably connected to the top of the circulating nipple (2); A plugging cap (322) detachably connected to the bottom of the filter screen pipe (321); A slotted tubing (325) connected to the bottom of the lower joint (4); A conversion pipe (324) arranged at the top of the slotted tubing (325); A plugging seat (323) detachably connected to the top of the conversion pipe (324); Fishing holes (326), with a plurality of them respectively penetrating through the plugging seat (323), and the plurality of fishing holes (326) respectively communicate the inside of the plugging seat (323) with the fishing annular cavity (33); Wherein, the top of the fishing outer pipe (31) is detachably connected to the circulating nipple (2), and the bottom is detachably connected to the lower joint (4). After the plugging cap (322) and the plugging seat (323) are respectively disassembled, the bottom of the filter screen pipe (321) can be directly connected to the conversion pipe (324) to realize the communication between the filter screen pipe (321) and the slotted tubing (325); The circulating nipple (2) is used to control the flow direction of the washing fluid, so that the washing fluid flows through the upper joint (1), the circulating nipple (2), the filter screen pipe (321), the conversion pipe (324), the slotted tubing (325), and the lower joint (4) in sequence, and returns to the wellhead through the wellbore annulus to realize positive circulation fishing; Or make the washing fluid flow through the upper joint (1), the circulating nipple (2), the wellbore annulus, the lower joint (4), the slotted tubing (325), the conversion pipe (324), the plugging seat (323), the fishing holes (326), the fishing annulus, and the filter screen pipe (321) in sequence, then enter the wellbore annulus through the circulating nipple (2) and return to the wellhead to realize reverse circulation fishing.

2. The fishing device according to claim 1, wherein, The circulating nipple (2) includes: A circulating outer pipe (201) connected to the top of the upper joint (1); A conversion joint (202) connected to the top of the circulating outer pipe (201) and the bottom to the fishing outer pipe (31); A circulating inner pipe (203) coaxially arranged inside the circulating outer pipe (201) and connected to the bottom of the conversion joint (202). A circulating cavity (204) is formed between the circulating inner pipe (203) and the circulating outer pipe (201); A sealing ball seat (205) connected to the top of the circulating inner pipe (203), and after an external steel ball is thrown, it can block the sealing ball seat (205); The first circulation holes (206) are multiple in number and are respectively arranged through the adapter (202). The multiple first circulation holes (206) are respectively communicated with the circulation cavity (204), and a first oil plug (207) is detachably connected in each first circulation hole (206). The support pads (208) are multiple in number and are respectively arranged on the circulation inner pipe (203). The multiple support pads (208) respectively pass through the circulation outer pipe (201). The second circulation holes (210) are multiple in group and are respectively arranged through the support pads (208). The second circulation holes (210) penetrate through the circulation inner pipe (203) and communicate the inside of the circulation inner pipe (203) with the wellbore annulus. A second oil plug (211) is detachably connected in each second circulation hole (210).

3. The fishing device according to claim 2, characterized in that, The first circulation holes (206) are arranged obliquely downward, and the second circulation holes (210) are arranged obliquely upward.

4. The fishing device according to claim 2, characterized in that, A plurality of relief holes (209) are arranged through the circulation outer pipe (201). The multiple support pads (208) respectively pass through the corresponding relief holes (209), and the support pads (208) are detachably connected to the circulation inner pipe (203).

5. The fishing device according to claim 4, characterized in that, A plurality of limit grooves (212) are arranged on the outer side wall of the circulation inner pipe (203). The multiple support pads (208) are respectively tightly clamped into the corresponding limit grooves (212).

6. The fishing device according to claim 2, wherein A setting valve cup (5) for setting an external steel ball is arranged at the bottom of the upper joint (1).

7. The salvage device according to claim 1, characterized in that, The plugging cap (322) is sleeved on the bottom of the filter screen pipe (321) and is threadedly connected to the filter screen pipe (321). The bottom of the plugging seat (323) is inserted into the conversion pipe (324) and is threadedly connected to the conversion pipe (324). The external thread at the bottom of the filter screen pipe (321) matches the internal thread at the top of the conversion pipe (324).

8. The fishing device according to claim 1, characterized in that Guide conical surfaces (327) are respectively arranged at the bottom of the plugging cap (322) and the top of the plugging seat (323).

9. The fishing device according to claim 1, characterized in that The outer side wall of the plugging cap (322) is in close fit with the inner side wall of the fishing outer pipe (31). A plurality of communication channels (328) are arranged on the outer side wall of the plugging cap (322), and the washing fluid can flow through the communication channels (328).

10. The fishing device according to claim 1, characterized in that, A plurality of support ribs (329) are arranged on the outer side wall of the plugging seat (323). The multiple support ribs (329) are respectively in close contact with the inner side wall of the fishing outer pipe (31), and the washing fluid can flow through the gaps between adjacent two support ribs (329).

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