Anti-extrusion high-air-tightness special-thread oil casing

Abstract

The utility model discloses an anti-extrusion high-air-tightness special-thread oil casing which is convenient to connect, high in connecting strength, good in sealing performance and good in anti-extrusion performance at the connecting position. Comprising casing pipe bodies and couplings, the couplings are arranged at the two ends of the casing pipe bodies in a sleeving mode and used for connecting the two adjacent casing pipe bodies, external thread sections are arranged at the two ends of the casing pipe bodies, and two internal thread sections corresponding to the external thread sections on the casing pipe bodies are arranged on the couplings. The two internal thread sections are matched with the external thread sections on the two adjacent casing pipe bodies, a sealing ring is fixedly arranged between the two internal thread sections, first sealing structures are arranged at the two ends of the coupling, second sealing structures corresponding to the first sealing structures are arranged at the positions, close to the external thread sections, of the casing pipe bodies, and the second sealing structures correspond to the second sealing structures. The second sealing structure comprises a sealing plate fixedly installed on the sleeve body, and a supporting circular truncated cone is fixedly arranged on the side, away from the external thread section, of the sealing plate.

Description

Technical Field

[0001] The utility model relates to the technical field of oil casing structures used in oil and gas drills, in particular to an anti-extrusion type high-gas-tight sealing special buckle oil casing. Background Art

[0002] Special oil pipes are mainly used for drilling oil and gas wells and the transportation of oil and gas. Special oil pipes usually include oil drill pipes, oil casing, pumping pipes, etc. Oil casing is a large-diameter pipe that plays the role of fixing the wall or wellbore of oil and natural gas wells. When in use, the oil casing is inserted into the wellbore and fixed with cement to ensure the smooth progress of the drilling process and the normal operation of the entire oil well after completion. Casings usually include coupling connection type and straight connection type. For coupling connection type oil casing, the pipe bodies are connected by couplings to form the entire oil casing.

[0003] For example, a Chinese patent with publication number CN219492214U discloses a new type of special buckle oil casing, including an oil casing body and a coupling, the oil casing body is connected by the coupling, the oil casing body and the coupling are both bilaterally symmetrical structures, and an anti-slip block is sleeved at the connection between the oil casing body and the coupling; the anti-slip block is annular, the left end of which is a small-diameter end connected to the oil casing body, and a plurality of pipe body limiting grooves are arranged at intervals on the inner circumferential surface of the small-diameter end, and the right end of which is a large-diameter end connected to the coupling, and a plurality of coupling limiting grooves are arranged at intervals on the inner circumferential surface of the large-diameter end.

[0004] This patent sets an anti-slip structure and uses an anti-slip block to limit the coupling and the casing body to prevent relative rotation between the two, avoid loosening of the connection, and ensure the sealing, thermal insulation and other properties of the casing. However, it makes the connection of the casing more complicated and the operation less convenient. At the same time, the anti-extrusion performance of the connection is poor. Utility Model Content

[0005] The technical problem to be solved by the utility model is to overcome the defects of the existing technical problems and provide an anti-extrusion type high air-tight special buckle oil casing, which is easy to connect, has high connection strength, good sealing performance, and good anti-extrusion performance at the connection.

[0006] In order to solve the above technical problems, the technical solution of the utility model is: an anti-extrusion high-gas-tight special buckle oil casing, comprising a casing body and a coupling, the coupling is sleeved on both ends of the casing body and is used to connect two adjacent casing bodies, both ends of the casing body are provided with external thread sections, the coupling is provided with two sections of internal thread sections corresponding to the external thread sections on the casing body, the two sections of the internal thread sections cooperate with the external thread sections on the two adjacent casing bodies, a sealing ring is fixedly provided between the two sections of the internal thread sections, a first sealing structure is provided at both ends of the coupling, a second sealing structure corresponding to the first sealing structure is provided on the casing body near the external thread section, the second sealing structure includes a sealing plate fixedly installed on the casing body, and a supporting frustum is fixedly provided on the side of the sealing plate away from the external thread section.

[0007] Furthermore, the inner diameter of the coupling corresponds to the outer diameter of the casing body, the inner diameter of the sealing ring corresponds to the inner diameter of the casing body, and two ends of the sealing ring are respectively abutted against two ends of two adjacent casing bodies.

[0008] Furthermore, both ends of the sleeve body are provided with abutment steps and connecting conical surfaces, the abutment steps are arranged between the external thread section and the connecting conical surface, and the sealing ring is provided with a sealing inclined surface corresponding to the connecting conical surface and a sealing straight surface connected to the sealing inclined surface.

[0009] Further, the abutting step abuts against the end surface of the sealing ring, the connecting conical surface abuts against the sealing inclined surface and forms an interference fit, and the end of the sleeve body abuts against the sealing straight surface.

[0010] Furthermore, the threads on the external thread section and the internal thread section are both trapezoidal threads.

[0011] Furthermore, the first sealing structure includes a sealing protrusion, a first outer sealing step and a second outer sealing step, the first outer sealing step and the second outer sealing step are respectively located on both sides of the sealing protrusion, and the first outer sealing step and the second outer sealing step are respectively connected to the inner wall and outer wall of the coupling on one side away from the sealing protrusion.

[0012] Furthermore, the sealing plate is located on the outer wall of the sleeve body close to the external thread section, and a sealing groove corresponding to the sealing protrusion is provided on one side of the sealing plate close to the external thread section.

[0013] Furthermore, the sealing protrusion is formed by connecting a first sealing cone surface, a sealing arc surface and a second sealing cone surface, the inclination directions of the first sealing cone surface and the second sealing cone surface are opposite, and a sealing arc surface is formed at the intersection of the first sealing cone surface and the second sealing cone surface, and the side of the first sealing cone surface away from the sealing arc surface is connected to the first outer sealing step, and the side of the second sealing cone surface away from the sealing arc surface is connected to the second outer sealing step.

[0014] Furthermore, the sealing groove includes a third sealing cone surface and a fourth sealing cone surface corresponding to the first sealing cone surface and the second sealing cone surface, the third sealing cone surface and the fourth sealing cone surface are connected, and a sealing gasket is provided at the connection between the third sealing cone surface and the fourth sealing cone surface.

[0015] By adopting the above technical solution, the utility model has the following beneficial effects:

[0016] 1. The connecting conical surface on the sleeve body and the sealing inclined surface on the sealing ring form an interference fit, and the ends of the sleeve body at both ends abut against the sealing straight surfaces at both ends of the sealing ring, which can improve the sealing performance of the sleeve body when connected;

[0017] 2. The first sealing structure cooperates with the second sealing structure to further improve the sealing performance during connection;

[0018] 3. The threads on both the external thread section and the internal thread section are trapezoidal threads, so that the internal and external threads are tightly attached to the conical surface and are not easy to loosen, which is beneficial to improve the connection strength when the casing body is connected;

[0019] 4. The connection strength of the casing body and the anti-extrusion performance of the connection can be improved by setting the sealing plate and the supporting truncated cone. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural schematic diagram of the anti-extrusion type high air-tight special buckle oil casing of the utility model;

[0021] Figure 2 for Figure 1 A magnified view of part A in FIG.

[0022] Figure 3 for Figure 1 Enlarged view of part B in .

[0023] Reference numerals: 1, casing body; 2, coupling; 10, external thread section; 11, second sealing structure;

[0024] 20. Internal thread section; 21. Sealing ring; 22. First sealing structure;

[0025] 101, abutting step; 102, connecting cone; 111, sealing plate; 112, supporting truncated table; 113, sealing groove;

[0026] 1131, third sealing cone surface; 1132, fourth sealing cone surface; 1133, sealing gasket;

[0027] 211. Seal inclined surface; 212. Sealing straight surface;

[0028] 221, first outer sealing step; 222, sealing protrusion; 223, second outer sealing step;

[0029] 2221, first sealing cone surface; 2222, sealing arc surface; 2223, second sealing cone surface. DETAILED DESCRIPTION

[0030] In order to make the content of the utility model more clearly understood, the utility model is further described in detail below based on specific embodiments and in conjunction with the accompanying drawings.

[0031] like Figure 1-3 As shown, in this embodiment, an anti-extrusion high-gas-tight special buckle oil casing is provided, including a casing body 1 and a coupling 2, the inner diameter of the coupling 2 corresponds to the outer diameter of the casing body 1, the coupling 2 is sleeved on both ends of the casing body 1 and is used to connect two adjacent casing bodies 1, both ends of the casing body 1 are provided with external thread sections 10, the coupling 2 is provided with two internal thread sections 20 corresponding to the external thread sections 10 on the casing body 1, the two internal thread sections 20 are matched with the external thread sections 10 on the two adjacent casing bodies 1, a sealing ring 21 is fixedly provided between the two internal thread sections 20, first sealing structures 22 are provided at both ends of the coupling 2, and a second sealing structure 11 corresponding to the first sealing structure 22 is provided on the casing body 1 near the external thread section 10.

[0032] like Figure 1-2 As shown, in this embodiment, the inner diameter of the sealing ring 21 corresponds to the inner diameter of the sleeve body 1, and the two ends of the sealing ring 21 are respectively abutted against the two ends of the two adjacent sleeve bodies 1. The two ends of the sleeve body 1 are provided with abutting steps 101 and connecting conical surfaces 102. The abutting steps 101 are arranged between the external thread section 10 and the connecting conical surface 102. The sealing ring 21 is provided with a sealing inclined surface 211 corresponding to the connecting conical surface 102 and a sealing straight surface 212 connected to the sealing inclined surface 211. When the two adjacent sleeve bodies 1 are connected, the abutting steps 101 at the two ends of the sleeve body 1 are respectively abutted against the end surfaces at the two ends of the sealing ring 21, the connecting conical surface 102 on the sleeve body 1 is abutted against the sealing inclined surface 211 on the sealing ring 21 and forms an interference fit, and the ends at the two ends of the sleeve body 1 are respectively abutted against the sealing straight surfaces 212 at the two ends of the sealing ring 21, which can improve the sealing performance of the sleeve body 1 when connected.

[0033] In this embodiment, the threads on the external thread section 10 and the internal thread section 20 are both trapezoidal threads, the tooth profile is an isosceles trapezoid, and the tooth profile angle is 30°, so that the internal and external threads are tightly attached to the conical surface and are not easy to loosen. The trapezoidal thread has a thick middle diameter and high strength, and is more wear-resistant than other threads, which is beneficial to improving the connection strength when the sleeve body 1 is connected.

[0034] like Figure 1-3 As shown, in this embodiment, the first sealing structure 22 includes a first sealing cone surface 2221, a sealing arc surface 2222, a second sealing cone surface 2223, a first outer sealing step 221 and a second outer sealing step 223. The first sealing cone surface 2221 and the second sealing cone surface 2223 are inclined in opposite directions. The intersection of the first sealing cone surface 2221 and the second sealing cone surface 2223 forms a sealing arc surface 2222. The side of the first sealing cone surface 2221 away from the sealing arc surface 2222 is connected to the first outer sealing step 221. The second sealing cone surface 2223 is connected to the second outer sealing step 223 on the side away from the sealing arc surface 2222. The first sealing cone surface 2221, the sealing arc surface 2222 and the second sealing cone surface 2223 form outward sealing protrusions 222 at both ends of the coupling 2. The first outer sealing step 221 and the second outer sealing step 223 are respectively located on both sides of the sealing protrusion 222. The first outer sealing step 221 and the second outer sealing step 223 are respectively connected to the inner wall and the outer wall of the coupling 2 on the side away from the sealing protrusion 222.

[0035] like Figure 1-3 As shown, in this embodiment, the second sealing structure 11 includes a sealing plate 111 fixedly mounted on the casing body 1, the sealing plate 111 is located on the outer wall of the casing body 1 near the external thread section 10, the sealing plate 111 is an annular plate, the inner diameter of the sealing plate 111 corresponds to the outer diameter of the casing body 1, and the outer diameter of the sealing plate 111 corresponds to the outer diameter of the coupling 2, so that when two adjacent casing bodies 1 are connected, the outer surface of the sealing plate 111 is flush with the outer surface of the coupling 2, and a supporting cone 112 is fixedly provided on the side of the sealing plate 111 away from the external thread section 10, the supporting cone 112 is fixedly sleeved on the outer wall of the casing body 1, and the outer diameters of both ends of the supporting cone 112 correspond to the outer diameters of the sealing plate 111 and the casing body 1 respectively. By arranging the sealing plate 111 and the supporting cone 112, the connection strength of the casing body 1 when connected can be improved, and at the same time, the sealing plate 111 and the supporting cone 112 can play a buffering role at the connection, thereby improving the anti-extrusion performance of the connection.

[0036] like Figure 1-3As shown, in this embodiment, a third sealing cone surface 1131 and a fourth sealing cone surface 1132 corresponding to the first sealing cone surface 2221 and the second sealing cone surface 2223 are provided on the side of the sealing plate 111 close to the external thread section 10, and the third sealing cone surface 1131 and the fourth sealing cone surface 1132 are connected, so that a sealing groove 113 for accommodating the sealing protrusion 222 is formed on the side of the sealing plate 111 close to the external thread section 10, and a sealing gasket 113 is provided at the connection between the third sealing cone surface 1131 and the fourth sealing cone surface 1132. 133. When two adjacent sleeve bodies 1 are connected, the first outer sealing step 221 and the second outer sealing step 223 on the coupling 2 abut against the end surface of the sealing plate 111 on the side close to the external thread section 10, the first sealing cone surface 2221 abuts against the third sealing cone surface 1131, and the second sealing cone surface 2223 abuts against the fourth sealing cone surface 1132, that is, the sealing protrusion 222 abuts against the sealing groove 113, and the sealing arc surface 2222 abuts against the sealing gasket 1133, thereby further improving the sealing performance during connection.

[0037] The connection method and advantages of the utility model are as follows: two casing bodies 1 are connected to the two ends of the coupling 2 through the cooperation of internal and external threads, so that the coupling 2 connects the two adjacent casing bodies 1. After the connection is completed, the abutting steps 101 at the two ends of the casing body 1 respectively abut on the end faces at the two ends of the sealing ring 21, and the connecting conical surface 102 on the casing body 1 and the sealing inclined surface 211 on the sealing ring 21 form an interference fit. The ends at the two ends of the casing body 1 respectively abut on the sealing straight surfaces 212 at the two ends of the sealing ring 21, which can improve the sealing performance of the casing body 1 when connected. The first outer sealing step 221 and the second outer sealing step 223 on the coupling 2 abut on the end face of the sealing plate 111 on the side close to the external thread section 10, and the first sealing conical surface 2221 and the third sealing conical surface 2223 are respectively connected. The sealing cone surface 1131 is abutted against each other, and the second sealing cone surface 2223 is abutted against the fourth sealing cone surface 1132, that is, the sealing protrusion 222 is abutted against the sealing groove 113, and the sealing arc surface 2222 is abutted against the sealing gasket 1133, further improving the sealing performance during connection; the threads on the external thread section 10 and the internal thread section 20 are both trapezoidal threads, so that the internal and external threads are tightly attached to the cone surface and are not easy to loosen, and the trapezoidal thread has a thick middle diameter and high strength, and is more wear-resistant than other threads, which is beneficial to improving the connection strength of the sleeve body 1 when connected. By arranging the sealing plate 111 and the supporting frustum 112, the connection strength of the sleeve body 1 when connected can be improved. At the same time, the sealing plate 111 and the supporting frustum 112 can play a buffering role at the connection, thereby improving the anti-extrusion performance of the connection.

[0038] The specific embodiments described above further illustrate the technical problems, technical solutions and beneficial effects solved by the present invention. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An anti-extrusion high air-tight special buckle oil casing, characterized by: The invention comprises a casing body (1) and a coupling (2), wherein the coupling (2) is sleeved on both ends of the casing body (1) and is used to connect two adjacent casing bodies (1), wherein both ends of the casing body (1) are provided with external thread sections (10), and the coupling (2) is provided with two internal thread sections (20) corresponding to the external thread sections (10) on the casing body (1), wherein the two internal thread sections (20) cooperate with the external thread sections (10) on the two adjacent casing bodies (1), and a sealing ring (21) is fixedly provided between the two internal thread sections (20), wherein both ends of the coupling (2) are provided with a first sealing structure (22), and a second sealing structure (11) corresponding to the first sealing structure (22) is provided on the casing body (1) near the external thread section (10).

2. According to claim 1, the anti-extrusion high air-tight special buckle oil casing is characterized by: The inner diameter of the coupling (2) corresponds to the outer diameter of the casing body (1), the inner diameter of the sealing ring (21) corresponds to the inner diameter of the casing body (1), and the two ends of the sealing ring (21) respectively abut against the two ends of two adjacent casing bodies (1).

3. The anti-extrusion high airtight special buckle oil casing according to claim 1 is characterized by: The two ends of the sleeve body (1) are provided with abutment steps (101) and connecting conical surfaces (102); the abutment steps (101) are arranged between the external thread section (10) and the connecting conical surface (102); the sealing ring (21) is provided with a sealing inclined surface (211) corresponding to the connecting conical surface (102) and a sealing straight surface (212) connected to the sealing inclined surface (211).

4. The anti-extrusion high air-tight special buckle oil casing according to claim 3 is characterized by: The abutment step (101) abuts against the end surface of the sealing ring (21), the connecting conical surface (102) abuts against the sealing inclined surface (211) to form an interference fit, and the end of the sleeve body (1) abuts against the sealing straight surface (212).

5. The anti-extrusion high airtight special buckle oil casing according to claim 1 is characterized by: The threads on the external thread section (10) and the internal thread section (20) are both trapezoidal threads.

6. The anti-extrusion high air-tight special buckle oil casing according to claim 1 is characterized by: The first sealing structure (22) comprises a sealing protrusion (222), a first outer sealing step (221) and a second outer sealing step (223), wherein the first outer sealing step (221) and the second outer sealing step (223) are respectively located on two sides of the sealing protrusion (222), and the first outer sealing step (221) and the second outer sealing step (223) are respectively connected to the inner wall and the outer wall of the coupling (2) at a side away from the sealing protrusion (222).

7. The anti-extrusion high air-tight special buckle oil casing according to claim 6 is characterized by: The second sealing structure (11) comprises a sealing plate (111) fixedly mounted on the sleeve body (1); the sealing plate (111) is located on the outer wall of the sleeve body (1) close to the external thread section (10); a supporting truncated table (112) is fixedly provided on a side of the sealing plate (111) away from the external thread section (10); and a sealing groove (113) corresponding to the sealing protrusion (222) is provided on a side of the sealing plate (111) close to the external thread section (10).

8. The anti-extrusion high air-tight special buckle oil casing according to claim 7 is characterized by: The sealing protrusion (222) is formed by connecting a first sealing cone surface (2221), a sealing arc surface (2222) and a second sealing cone surface (2223); the first sealing cone surface (2221) and the second sealing cone surface (2223) are inclined in opposite directions; a sealing arc surface (2222) is formed at the intersection of the first sealing cone surface (2221) and the second sealing cone surface (2223); a side of the first sealing cone surface (2221) away from the sealing arc surface (2222) is connected to the first outer sealing step (221); and a side of the second sealing cone surface (2223) away from the sealing arc surface (2222) is connected to the second outer sealing step (223).

9. The anti-extrusion high air-tight special buckle oil casing according to claim 8, characterized in that: The sealing groove (113) comprises a third sealing cone surface (1131) and a fourth sealing cone surface (1132) corresponding to the first sealing cone surface (2221) and the second sealing cone surface (2223); the third sealing cone surface (1131) and the fourth sealing cone surface (1132) are connected; and a sealing gasket (1133) is provided at the connection between the third sealing cone surface (1131) and the fourth sealing cone surface (1132).

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