Well cementation pup joint device

Abstract

The invention discloses a well cementation pup joint device which comprises an outer cylinder, an annular protrusion is arranged in the middle of the inner wall of the outer cylinder, and the annular protrusion divides the interior of the outer cylinder into two independent and communicated connecting areas. A protruding ring is further formed in the inner side area of the annular protrusion. The two sets of connecting assemblies are symmetrically arranged at the upper end and the lower end of the interior of the outer barrel, and each set of connecting assemblies are distributed around the axis of the outer barrel at equal angles; the connecting assembly is composed of a threaded piece, an adjusting plate and a mounting plate. In the invention, a plurality of threaded sheets with arc-shaped structures are adopted to replace an original threaded structure, in connection, the threaded sheets can be tightly attached to a pipeline to form stable threaded connection with the pipeline, and in later separation, if a traditional upward-screwing disassembly mode fails, the pipeline only needs to be continuously screwed downwards, and the adjusting plate is propped against, so that the pipeline can be disassembled, and the pipeline can be disassembled. And downward pressure is continuously applied to the threaded pieces, so that the threaded pieces can be easily damaged, threaded connection between the threaded pieces and the pipeline is damaged, and smooth separation of the pipeline is achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of petroleum cementing equipment, and in particular relates to a cementing short-circuit device. Background Art

[0002] The cementing short-circuit device is a special device used in oil cementing operations. It is mainly used to connect casing and ensure the stability and sealing of casing during cementing. It forms a reliable connection between casings so that cement slurry can be evenly injected into the annular space between the wellbore and casing, thus completing the cementing operation.

[0003] In the complex and delicate process of cementing, a crucial link is to accurately connect the pipeline through a special casing structure and then insert it into the wellbore to perform cementing operations. This step not only requires a high degree of technical precision, but also requires ensuring the stability and sealing of the connection to effectively prevent well fluid leakage, ensure operational safety and the normal operation of subsequent oil wells. However, after the cementing task is successfully completed, the challenge is shifted to how to safely and efficiently separate the pipeline from the casing.

[0004] In actual operation, threaded connection is often used to achieve a tight connection between the pipe and the casing. This design is theoretically easy to install and disassemble. However, the reality is often not satisfactory, especially after being subjected to the test of high pressure, high temperature and corrosive environment underground for a long time, the threaded connection may have a problem of reduced fit due to wear, corrosion or over-tightening, and the pipe cannot be screwed outwards, but can be screwed inwards, making it impossible to separate and disassemble the pipe and casing. This "only in but not out" phenomenon not only seriously hinders the progress of subsequent work, but may also cause equipment damage due to forced separation, and even cause safety accidents. Summary of the invention

[0005] The object of the present invention is to provide a cementing short-circuit device to solve the problem that the pipe and the casing cannot be screwed up and separated in the existing cementing operation mentioned in the above background technology.

[0006] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a cementing short-circuit device, comprising an outer cylinder, an annular protrusion is provided at the middle position of the inner wall, the annular protrusion divides the inner part of the outer cylinder into two independent and connected connection areas; a convex ring is also formed in the inner area of ​​the annular protrusion; two groups of connecting components are provided, and are symmetrically arranged at the upper and lower ends of the inner part of the outer cylinder, and each group of connecting components is distributed at equal angles around the axis of the outer cylinder; the connecting components are composed of a threaded sheet, an adjusting plate, and a mounting plate, wherein the bottom of the mounting plate is fixed on the annular protrusion, and the threaded sheet is arranged on the top of the mounting plate, so that The adjusting plate is located as a whole in the annular area between the threaded sheet and the outer cylinder, and the top end of the adjusting plate is fixed to the top of the outer surface of the threaded sheet, while the bottom end of the adjusting plate passes through the mounting plate through bending and extends horizontally toward the central area of ​​the outer cylinder; the adjusting plate is fixedly connected to the mounting plate and the threaded sheet; the threaded sheet is synchronously displaced by pressing down the adjusting plate, so as to achieve separation of the threaded sheet and the external pipeline; and a sealing spacer is also included; one end of the sealing spacer is overlapped on the convex ring, and the other end is on the connecting assembly, and the sealing of the connecting assembly and the outer cylinder is achieved through the sealing spacer.

[0007] As a preferred technical solution in the present invention, a slot for the bottom of the adjustment plate to pass through is provided on the surface of the mounting plate, a welding spot portion is formed between the adjusting plate and the top surface of the slot, and the rigid connection between the adjusting plate and the mounting plate is realized by the welding spot portion. A fixing plate is also fixed on the inner side surface of the adjusting plate, and the fixing plate is fixed to the bottom area of ​​the threaded plate. The end surface of the horizontal end of the adjusting plate is formed with an inclined portion that abuts against the external pipe. In normal connection, the driving threshold is set for the external device so that after the pipe is connected to the threaded plate, it stops when the upper ring is squeezed but the welding spot portion is not destroyed. The inclined portion is in compression contact with the pipe. When the traditional upward rotation separation method cannot achieve disassembly, the pipe is rotated, and the pipe will first squeeze the adjusting plate, so that part of the welding spot portion is first destroyed. At this time, the rigid connection between the adjusting plate and the mounting plate is removed. At this time, the pipe will contact the inclined portion during the continuous downward pressure. At this time, the adjusting plate as a whole moves toward the middle of the inner wall of the outer cylinder in an inclined direction, and the adjusting plate is pushed toward the direction of the outer cylinder through the inclined portion. At this time, the adjusting plate synchronously drives the threaded plate to move through the fixing plate, thereby realizing the separation of the threaded plate and the pipe.

[0008] As a preferred technical solution in the present invention, the adjusting plate as a whole is an arc-shaped plate body with two sections of unequal slopes, and a corner point is formed in the upper area of ​​the adjusting plate, the corner point contacts the inner wall of the outer cylinder, and an arc-shaped guide rod is provided in the angle area formed by the corner point and the upper part of the threaded sheet, the guide rod contacts the inner wall of the threaded sheet, and a fixing block is fixed at one end of the guide rod, and the fixing block is fixed on the inner wall of the outer cylinder. When the adjusting plate is pushed by the pipeline and moves toward the inner wall of the outer cylinder, the inner wall of the angle area of ​​the adjusting plate gradually resists the guide rod, and at this time the guide rod can force the upper area of ​​the adjusting plate to produce a slight deformation, that is, the upper area of ​​the adjusting plate moves toward the inner wall of the outer cylinder. At this time, the threaded sheet fixed to the top of the adjusting plate will also tilt toward the inner wall of the outer cylinder, and at the same time, the threaded sheet can be driven by the fixing sheet to move closer to the outer cylinder as a whole, and the threaded sheet and the pipeline can be separated.

[0009] As a preferred technical solution in the present invention, the sealing spacer includes an upper ring, a lower ring, and a dividing block arranged at equal angles therebetween, the dividing block is located between every two adjacent connecting components, and is abutted against the side walls of the mounting plate and the threaded sheet, so as to seal the distance between every two adjacent connecting components, the lower ring is located between the horizontal area of ​​the adjusting plate and the convex ring, and is abutted against the two respectively, so as to seal the distance between the entire connecting component and the bottom area of ​​the outer cylinder, and achieve the purpose of leakage prevention, and at the same time, in the downward pressing adjusting plate, the sealing spacer is always in a compressed state, and its sealing performance is not affected; the upper ring is placed at the top position of the horizontal area of ​​the adjusting plate, and during installation, it can be squeezed and connected with the external pipe to achieve sealing.

[0010] As a preferred technical solution in the present invention, the inner wall of the mounting plate is a smooth curved surface, which contacts the pipe with a curved surface, thereby ensuring that the subsequent separation of the pipe is not affected. The inner wall of the bottom of the threaded sheet has an inclined portion, which extends toward the inner wall of the outer tube to avoid the bottom of the threaded sheet from abutting against the pipe when the threaded sheet is tilted.

[0011] As a preferred technical solution in the present invention, the initial state of the threaded sheet and the mounting plate is vertical to ensure normal connection, and the contact end surface of the mounting plate and the threaded sheet is a planar connection, which is convenient for rapid position adjustment of the threaded sheet later.

[0012] As a preferred technical solution in the present invention, the convex ring is located in the middle of the annular protrusion, and the inner diameter of the convex ring is equal to the inner diameter of the sealing spacer.

[0013] As a preferred technical solution in the present invention, sealing rubber rings are further provided at the end faces of both ends of the outer cylinder, and the vertical projection of the sealing rubber ring covers the vertical projection area of ​​the entire threaded sheet to avoid leakage areas of the threaded sheet. In actual use, the sealing rubber ring can be installed by gluing, and the sealing rubber rings are used to seal the positions of the two ends of the outer cylinder to avoid the entry of external objects. At the same time, in conjunction with the sealing spacer, a double sealing effect can be achieved.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] In the present invention, multiple arc-shaped threaded sheets are used to replace the original threaded structure. During the connection, the threaded sheets can fit tightly on the pipe to form a stable threaded connection with the pipe. During the later separation, if the traditional upward screwing disassembly method fails, it is only necessary to continue to screw down the pipe, press against the adjustment plate, and continue to apply downward force to it, so that these threaded sheets can be easily destroyed, so that the threaded connection between the threaded sheets and the pipe is destroyed, thereby achieving smooth separation of the pipe. This design not only retains the stability of the threaded connection, but also makes the sleeve flexible and removable. At the same time, in order to ensure the sealing during the connection process, a sealing spacer and a sealing rubber ring are also provided, which can be tightly filled between the threaded sheets to effectively block the possibility of well fluid penetration. Even in extreme working environments, the sealing ring of the entire connection system can be guaranteed. This design effectively solves the problem of disassembly of the traditional threaded structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the overall structure of the cementing short-circuit device;

[0017] Figure 2 It is a cross-sectional view of the cementing short-circuit device;

[0018] Figure 3 for Figure 2 A magnified schematic diagram of the middle A area;

[0019] Figure 4 for Figure 2 A magnified schematic diagram of the middle B area;

[0020] Figure 5 is a schematic diagram of the structure of the connection components;

[0021] Figure 6 It is a schematic diagram of the connection between the adjustment plate and the mounting plate;

[0022] Figure 7 It is a schematic diagram of the structure of the sealing spacer.

[0023] In the figure:

[0024] 100, outer cylinder; 101, sealing rubber ring; 102, convex ring; 103, guide rod; 104, fixing block;

[0025] 200, connecting assembly; 201, threaded sheet;

[0026] 202, adjustment plate; 202a, inclined portion; 202b, welding point portion; 202c, fixing plate;

[0027] 203, mounting plate; 203a, slot;

[0028] 300, sealing spacer; 301, upper ring; 302, separator block; 303, lower ring. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] See also Figures 1 to 7 The present invention provides a technical solution: a cementing short-circuit device, comprising

[0031] The outer cylinder 100 has an annular protrusion at the middle of the inner wall, which divides the inner part of the outer cylinder 100 into two independent and connected connection areas; a convex ring 102 is also formed in the inner area of ​​the annular protrusion;

[0032] The connection components 200 are provided in two groups and are symmetrically placed at the upper and lower ends of the outer cylinder 100. Each group of connection components 200 is distributed at equal angles around the axis of the outer cylinder 100.

[0033] The connecting assembly 200 is composed of a threaded sheet 201, an adjusting plate 202, and a mounting plate 203, wherein the bottom of the mounting plate 203 is fixed on the annular protrusion, and can be fixed specifically by welding, and the threaded sheet 201 is arranged on the top of the mounting plate 203, and the adjusting plate 202 is located in the annular region between the threaded sheet 201 and the outer tube 100 as a whole. During the separation of the threaded sheet 201 in the later stage, the adjusting plate 202 will also move in the annular region as a whole, and the top of the adjusting plate 202 is fixed to the top of the outer surface of the threaded sheet 201, and the bottom of the adjusting plate 202 passes through the mounting plate 203 through bending and extends horizontally toward the center region of the outer tube 100; the adjusting plate 202 is fixedly connected to the mounting plate 203 and the threaded sheet 201; the threaded sheet 201 is synchronously dislocated by pressing down the adjusting plate 202, so as to separate the threaded sheet 201 from the external pipe, and facilitate the subsequent disassembly;

[0034] It also includes a sealing spacer 300; one end of the sealing spacer 300 is overlapped on the convex ring 102, and the other end is located on the connecting component 200, and the sealing spacer 300 is used to achieve sealing between the connecting component 200 and the outer cylinder 100.

[0035] In this embodiment, a slot 203a is provided on the surface of the mounting plate 203 for the bottom of the adjusting plate 202 to pass through, and a welding point portion 202b is formed between the adjusting plate 202 and the top surface of the slot 203a, and the rigid connection between the adjusting plate 202 and the mounting plate 203 is realized by the welding point portion 202b. A fixing plate 202c is also fixed to the inner side surface of the adjusting plate 202, and the fixing plate 202c is fixed to the bottom area of ​​the threaded plate 201. The end surface of the horizontal end of the adjusting plate 202 is formed with an inclined portion 202a that abuts against the external pipe. In normal connection, the driving threshold of the external device is set so that after the pipe is connected to the threaded plate 201, when the upper ring 301 is squeezed, the welding point portion 202b will not be damaged. When the adjusting plate 202 is stopped in the state, the inclined portion 202a is squeezed and contacted with the pipe. When the traditional upward rotation separation method cannot achieve disassembly, the pipe is rotated, and the pipe will first squeeze the adjusting plate 202, so that the welding point portion 202b is first destroyed. At this time, the rigid connection between the adjusting plate 202 and the mounting plate 203 is removed. At this time, during the continuous downward pressure of the pipe, it will contact with the inclined portion 202a. At this time, the adjusting plate 202 as a whole moves toward the middle of the inner wall of the outer cylinder 100 in an inclined direction, and the adjusting plate 202 is pushed toward the direction of the outer cylinder 100 through the inclined portion 202a. At this time, the adjusting plate 202 synchronously drives the threaded piece 201 to move through the fixing piece 202c, so as to realize the separation of the threaded piece 201 from the pipe.

[0036] In this embodiment, the adjusting plate 202 is a curved plate body with two sections of unequal slopes, and a corner point is formed in the upper area of ​​the adjusting plate 202, and the corner point contacts the inner wall of the outer cylinder 100, and an arc-shaped guide rod 103 is provided in the angle area formed by the corner point and the upper part of the threaded sheet 201, and the guide rod 103 contacts the inner wall of the threaded sheet 201, and a fixing block 104 is fixed to one end of the guide rod 103, and the fixing block 104 is fixed to the inner wall of the outer cylinder 100. When the adjusting plate 202 is pushed by the pipeline and moves toward the inner wall of the outer cylinder 100, When the inner wall moves, the angle area of ​​the adjustment plate 202 gradually contacts the guide rod 103. At this time, the guide rod 103 can force the upper area of ​​the adjustment plate 202 to produce a slight deformation, that is, the upper area of ​​the adjustment plate 202 moves toward the inner wall of the outer cylinder 100. At this time, the threaded piece 201 fixed to the top of the adjustment plate 202 will also tilt toward the inner wall of the outer cylinder 100. At the same time, the threaded piece 201 can be driven by the fixing piece 202c to move closer to the outer cylinder 100 as a whole. At this time, the threaded piece 201 can be separated from the pipeline.

[0037] In this embodiment, the sealing spacer 300 includes an upper ring 301, a lower ring 303, and a partition block 302 arranged at an equal angle therebetween. The partition block 302 is located between every two adjacent connecting components 200 and abuts against the side walls of the mounting plate 203 and the threaded sheet 201, thereby sealing the distance between every two adjacent connecting components 200. The lower ring 303 is located between the horizontal area of ​​the adjusting plate 202 and the convex ring 102 and abuts against the two respectively, thereby sealing the gap between the entire connecting component 200 and the bottom area of ​​the outer cylinder 100 to achieve the purpose of leakage prevention. At the same time, when the adjusting plate 202 is pressed down, the sealing spacer 300 is always in a compressed state and its sealing performance is not affected. The upper ring 301 is placed at the top position of the horizontal area of ​​the adjusting plate 202. During installation, it can be squeezed and connected with the external pipeline to achieve sealing.

[0038] In this embodiment, the inner wall of the mounting plate 203 is a smooth curved surface, which contacts the pipe with a curved surface, thereby ensuring that the subsequent separation of the pipe is not affected. The inner wall at the bottom of the threaded sheet 201 has an inclined portion, which extends toward the inner wall of the outer tube 100 to avoid the bottom of the threaded sheet 201 from abutting against the pipe when the threaded sheet 201 is tilted.

[0039] In this embodiment, the initial state of the threaded piece 201 and the mounting plate 203 is vertical to ensure normal connection, and the contact end surfaces of the mounting plate 203 and the threaded piece 201 are planarly connected, which facilitates the rapid position adjustment of the threaded piece 201 later.

[0040] In this embodiment, the protruding ring 102 is located in the middle of the annular protrusion, and the inner diameter of the protruding ring 102 is equal to the inner diameter of the sealing spacer 300 .

[0041] In this embodiment, sealing rubber rings 101 are further provided at the end faces of both ends of the outer cylinder 100. The vertical projection of the sealing rubber ring 101 covers the vertical projection area of ​​the entire threaded sheet 201 to avoid leakage areas of the threaded sheet 201. In actual use, the sealing rubber ring 101 can be installed by gluing, and the sealing rubber ring 101 is used to seal the positions of both ends of the outer cylinder 100 to prevent the entry of external objects. At the same time, in conjunction with the sealing spacer 300, a double sealing effect can be achieved to ensure that normal processing is not affected.

[0042] In the present invention, first refer to Figure 3 , set the rotation speed and time of the external pipe clamping device so that when the pipe is installed with the outer tube 100, it will first be threadedly connected with the threaded sheet 201, and in the continuous downward rotation, the pipe will contact and squeeze the upper ring 301. At this time, the downward rotation of the pipe reaches the set time, so that the pipe squeezes the upper ring 301 but does not damage the welding point 202b, and the connection can be sealed at this time;

[0043] In the later disassembly, the device for clamping the pipe externally is rotated in the reverse direction to loosen the pipe and separate the pipe from the outer cylinder 100. When the conventional upward rotation separation method cannot achieve disassembly, the pipe is stopped from rotating in the reverse direction and is rotated in the direction of normal tightening of the pipe. The pipe will first squeeze the adjustment plate 202 through the upper ring 301, so that the part of the welding point 202b is subjected to downward pressure and is first destroyed. At this time, the rigid connection between the adjustment plate 202 and the mounting plate 203 is removed. At this time, the pipe will be continuously rotated downward and will be connected with the inclined part 203. 02a contact, that is, the inclined portion 202a is in squeeze contact with the pipeline, at this time, the adjusting plate 202 as a whole moves toward the middle of the inner wall of the outer cylinder 100 in an inclined direction, wherein the width of the slot 203a is greater than the width of the horizontal portion of the adjusting plate 202, to ensure the normal movement of the adjusting plate 202. During this period, the adjusting plate 202 is pushed toward the direction of the outer cylinder 100 by the inclined portion 202a, and the adjusting plate 202 synchronously drives the threaded piece 201 to move through the fixing piece 202c, thereby realizing the preliminary separation of the threaded piece 201 from the pipeline;

[0044] Reference Figure 4 When the adjusting plate 202 is pushed by the pipe and moves toward the inner wall of the outer cylinder 100, the adjusting plate 202 as a whole will move toward the middle area of ​​the outer cylinder 100, that is, the position of the adjusting plate 202 toward the opening of the outer cylinder 100 will move toward the inner direction of the outer cylinder 100. At this time, the angle area of ​​the adjusting plate 202 gradually abuts against the guide rod 103. For details, please refer to Figure 5 and Figure 6 , and the adjusting plate 202, under the limitation of the guide rod 103, can force the upper area of ​​the adjusting plate 202 to produce a slight deformation, that is, the upper area of ​​the adjusting plate 202 moves toward the inner wall of the outer cylinder 100. At this time, the threaded piece 201 fixed to the top of the adjusting plate 202 will also tilt toward the inner wall of the outer cylinder 100. Driven by the fixed piece 202c, the threaded piece 201 as a whole moves toward the outer cylinder 100. At this time, the threaded piece 201 can be separated from the pipeline, and then the separated pipeline can be directly pulled out or rotated forwards or backwards to complete the entire disassembly action. At this time, the threaded piece 201 at the lower part of the outer cylinder 100 still maintains a normal connection with the lower pipeline, and can be disassembled normally later.

[0045] Although embodiments of the present invention have been shown and described (see the above detailed description for details), it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. Cementing short-circuit device, including The outer cylinder (100) has an annular protrusion at the middle of the inner wall; a convex ring (102) is also formed in the inner area of ​​the annular protrusion; Features: The connection components (200) are provided in two groups and are symmetrically arranged at the upper and lower ends of the outer cylinder (100), and each group of the connection components (200) is distributed at equal angles around the axis of the outer cylinder (100); The connection assembly (200) is composed of a threaded sheet (201), an adjustment plate (202), and a mounting plate (203), wherein the bottom of the mounting plate (203) is fixedly arranged on the annular protrusion, and the threaded sheet (201) is arranged on the top of the mounting plate (203), and the adjustment plate (202) is entirely located in the annular region between the threaded sheet (201) and the outer cylinder (100), and the top of the adjustment plate (202) is fixed to the top of the outer surface of the threaded sheet (201), and the bottom of the adjustment plate (202) passes through the mounting plate (203) by bending and extends horizontally toward the central region of the outer cylinder (100); the adjustment plate (202) is fixedly connected to the mounting plate (203) and the threaded sheet (201); It also includes a sealing spacer (300); one end of the sealing spacer (300) is overlapped on the convex ring (102), and the other end is located on the connecting component (200).

2. The cementing short-circuit device according to claim 1, characterized in that: The surface of the mounting plate (203) is provided with a slot (203a) for the bottom of the adjustment plate (202) to pass through, a welding point portion (202b) is formed between the adjustment plate (202) and the top surface of the slot (203a), a fixing plate (202c) is also fixed to the inner side surface of the adjustment plate (202), and the fixing plate (202c) is fixed to the bottom area of ​​the threaded plate (201), and the end surface of the horizontal end of the adjustment plate (202) is formed with an inclined portion (202a) that abuts against the external pipe.

3. The cementing short-circuit device according to claim 2, characterized in that: The adjusting plate (202) is an overall arc-shaped plate body having two sections with different slopes, and a corner point is formed in the upper region of the adjusting plate (202), the corner point is in contact with the inner wall of the outer cylinder (100), and an arc-shaped guide rod (103) is provided in the angle region formed by the corner point and the upper part of the threaded sheet (201), the guide rod (103) is in contact with the inner wall of the threaded sheet (201), and a fixing block (104) is fixed to one end of the guide rod (103), and the fixing block (104) is fixed to the inner wall of the outer cylinder (100).

4. The cementing short-circuit device according to claim 3, characterized in that: The sealing spacer (300) comprises an upper ring (301), a lower ring (303), and a partition block (302) arranged at an equal angle therebetween; the partition block (302) is located between every two adjacent connection components (200) and abuts against the side walls of the mounting plate (203) and the threaded sheet (201); the lower ring (303) is located between the horizontal area of ​​the adjustment plate (202) and the convex ring (102) and abuts against both respectively; the upper ring (301) is placed at the top position of the horizontal area of ​​the adjustment plate (202).

5. The cementing short-circuit device according to claim 2, characterized in that: The inner wall of the mounting plate (203) is in the shape of a smooth curved surface, and the inner wall of the bottom of the threaded sheet (201) has an inclined portion, which extends toward the inner wall of the outer cylinder (100).

6. The cementing short-circuit device according to claim 5, characterized in that: The initial states of the threaded sheet (201) and the mounting plate (203) are vertical, and the contact end surfaces of the mounting plate (203) and the threaded sheet (201) are planarly connected.

7. The cementing short-circuit device according to claim 1, characterized in that: The convex ring (102) is located in the middle of the annular protrusion, and the inner diameter of the convex ring (102) is equal to the inner diameter of the sealing spacer (300).

8. The cementing short-circuit device according to claim 1, characterized in that: Sealing rubber rings (101) are also provided at the end surfaces of both ends of the outer cylinder (100), and the vertical projection of the sealing rubber ring (101) covers the vertical projection area of ​​the entire threaded sheet (201).

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