Oil well pipe special screwed joint suitable for being used in harsh environment

Abstract

The utility model discloses a special screwed joint for an oil well pipe, which is suitable for being used in a harsh environment. The special screwed joint comprises a pipe, a hydraulic impact resistance unloading joint and a coupling, external thread structures I are symmetrically arranged on the outer circumferential surfaces of the two ends of the pipe; the outer thread structure I comprises an outer thread, an outer sealing cylindrical shoulder, an outer cylindrical surface, an outer sealing circular arc, an outer sealing locking inclined surface and an inner boring hole which are sequentially arranged from the middle to the end surface; the left end of the hydraulic impact resistance-removing connector is provided with an internal thread structure II connected with one end of the pipe, the right end of the hydraulic impact resistance-removing connector is provided with an external thread structure II connected with one end of the coupling, the outer circumference of the connector is provided with an impact positioning block, and the hydraulic impact resistance-removing assembly is arranged in the connector. The bearing surfaces of the male buckle and the female buckle are in negative-angle interference fit, so that the compression strength and the slippage resistance are greatly improved, and the connection strength under complex well conditions such as a highly-deviated well, a horizontal well and a large-dog-leg-degree well is ensured.

Description

Technical Field

[0001] This utility model relates to the field of threaded connection technology for oil and gas drilling and production pipes, specifically to a special threaded joint for oil well pipes suitable for use in harsh environments. Background Technology

[0002] With the further development of the petroleum industry, especially in special well conditions such as highly deviated wells, horizontal wells, and wells with large doglegs, as well as in harsh environments such as irregular well diameters and the risk of blockage and jamming, there are higher requirements for the compression resistance, slippage resistance, sealing performance, and jamming resistance of oil well tubing. In order to meet the needs of the industry, it is necessary to improve the structure of traditional oil well tubing. Utility Model Content

[0003] The purpose of this utility model is to provide a special threaded joint for oil well pipes suitable for use in harsh environments, so as to meet the needs of the industry.

[0004] To achieve the above objectives, the technical solution provided by this utility model is as follows:

[0005] A special threaded joint for oil well pipes suitable for use in harsh environments, comprising a pipe, a hydraulic impact relief joint, and a coupling;

[0006] The outer circumferential surfaces at both ends of the pipe are symmetrically provided with external thread structure I; the external thread structure I includes an external thread, an external sealing cylindrical shoulder, an external cylindrical surface, an external sealing arc, an external sealing stop bevel, and an internal boring hole arranged sequentially from the middle to the end face; the external thread is a tapered pipe thread;

[0007] The inner circumferential surfaces at both ends of the coupling are symmetrically provided with internal thread structure I; the internal thread structure I includes an internal thread, an inner cylindrical surface, an inner sealing conical surface, an inner arc, and an inner sealing stop inclined surface arranged sequentially from the end face to the middle; the internal thread is a tapered pipe thread used in conjunction with the external thread.

[0008] The left end of the hydraulic impact relief joint is provided with an internal thread structure II connected to one end of the pipe, and the right end is provided with an external thread structure II connected to one end of the coupling. An impact positioning block is provided on the outer circumference of the joint, and a hydraulic impact relief assembly is provided inside. The internal thread structure II is the same as the internal thread structure I, and the external thread structure II is the same as the external thread structure I.

[0009] When rotating and meshing, the external thread is screwed into the corresponding position of the internal thread. The external sealing cylindrical shoulder, external sealing arc, and external sealing stop slope of the external thread gradually come into contact with the inner cylindrical surface, inner sealing conical surface, and inner sealing stop slope of the internal thread structure I until an interference fit is achieved.

[0010] The number of impact positioning blocks is 4 to 6.

[0011] The hydraulic impact relief assembly includes an upper valve core, a spring, a lower valve sleeve, and a positioning snap ring arranged sequentially from left to right. The outer circumference of the small end of the upper valve core is provided with 4 to 6 radial through holes. The impact positioning block is provided with a cylindrical through hole. The small end of the upper valve core is inserted into the cavity of the lower valve sleeve and slidably connected. The spring is connected between the upper valve core and the lower valve sleeve. During operation, the radial through holes communicate with the cylindrical through holes.

[0012] The upper valve core and the lower valve sleeve are both provided with grooves on their outer circumferences, and the grooves are filled with O-rings for sealing.

[0013] The upper valve core and the lower valve sleeve are made of aluminum alloy.

[0014] Wherein, the guide angle of the external thread and the internal thread is 25°, and the bearing surface angle is -5°.

[0015] Wherein, the outer diameter of the pipe is 60.32 to 339.7 mm, the outer cylindrical surface diameter is equal to the inner cylindrical surface diameter, and the inner boring diameter is equal to the inner diameter of the coupling.

[0016] Specifically, when the outer diameter of the pipe is 60.32 to 73.02 mm, the thread pitch is 3.18 mm; when the outer diameter is 88.9 to 114.3 mm, the thread pitch is 4.23 mm; and when the outer diameter is 127.00 to 339.7 mm, the thread pitch is 5.08 mm.

[0017] Wherein, the outer diameter of the impact positioning block is greater than the outer diameter of the coupling, which is greater than the outer diameter of the specification.

[0018] Compared with the prior art, the beneficial effects of this utility model are:

[0019] (1) The male and female buckle bearing surfaces of this utility model adopt a negative angle interference fit design, which greatly improves the compressive strength and anti-slip capability, ensuring the connection strength under complex well conditions such as large-angle wells, horizontal wells, and large doglegs; This utility model adopts a hydraulic impact relief valve design. Under medium and low pressure conditions, due to the support of the spring, the radial through hole and the cylindrical through hole are connected, and the mud is sprayed out from the cylindrical through hole, spraying onto the well wall to remove irregular well walls or obstructions; During the later cementing process, under high pressure, the upper valve core moves, causing the radial through hole to be blocked by the lower valve sleeve, thus preventing the mud from being sprayed out from the cylindrical through hole, and the mud cements normally. This greatly reduces the risk of jamming in harsh environments such as irregular well diameters, easy diameter reduction, and easy block falling, and greatly improves the safety and reliability under complex conditions;

[0020] (2) This utility model adopts the design of interference fit between metal arc surface and metal sealing cone surface to ensure sealing performance under complex well conditions such as large deviated well, horizontal well, and large dogleg degree.

[0021] (3) This utility model adopts an internal parallel design with the inner diameter of the male thread inner boring hole being consistent with that of the coupling inner diameter, which avoids the influence of turbulence and greatly improves the efficiency of subsequent hydraulic construction while ensuring quality. Attached Figure Description

[0022] Figure 1 The figure shown is a schematic diagram of the overall structure of the connector provided in an embodiment of this utility model;

[0023] Figure 2 The diagram shown is a schematic diagram of the meshing assembly of the internal and external thread structure provided in an embodiment of this utility model;

[0024] Figure 3 The figure shown is a cross-sectional view of the internal and external threads provided in an embodiment of this utility model;

[0025] Figure 4 The figure shown is a schematic diagram of the pipe cross-section provided in an embodiment of this utility model;

[0026] Figure 5 The figure shown is a schematic diagram of the front end cross-section of the pipe provided in an embodiment of this utility model;

[0027] Figure 6 The diagram shown is a schematic diagram of the coupling structure provided in an embodiment of this utility model;

[0028] Figure 7 The diagram shown is a schematic diagram of the coupling tail end structure provided in an embodiment of this utility model;

[0029] Figure 8 The diagram shown is a schematic diagram of the hydraulic impact relief connector structure provided in an embodiment of this utility model.

[0030] Figure 9 The diagram shown is a schematic diagram of the upper valve core structure provided in an embodiment of this utility model;

[0031] In the diagram: 1-pipe, 2-hydraulic impact relief connector, 3-coupling, 11-external thread structure I, 12-external thread structure II, 111-external thread, 112-external sealing cylindrical shoulder, 113-external cylindrical surface, 114-external sealing arc, 115-external sealing stop bevel, 116-internal bore, 21-impact positioning block, 22-hydraulic impact relief assembly, 211-upper valve core, 212-groove, 213-cylindrical through hole, 214-spring, 215-lower valve sleeve, 216 - Positioning snap ring, 2111 - Radial through hole, 31 - Internal thread structure I, 32 - Internal thread structure II, 311 - Internal thread, 312 - Inner cylindrical surface, 313 - Inner sealing conical surface, 314 - Inner arc, 315 - Inner sealing stop slope, D - Specification outer diameter, D1 - Outer cylindrical surface diameter, D2 - Coupling outer diameter, D3 - Impact positioning block outer diameter, d1 - Inner boring diameter, d2 - Inner cylindrical surface diameter, d3 - Coupling inner diameter, P - Thread pitch, B - Guide angle, A - Bearing surface angle. Detailed Implementation

[0032] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0033] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", 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 this utility model and simplifying the description, and are not intended to indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0034] In the description of this patent, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "setting" should be interpreted broadly. For example, they can refer to a fixed connection or setting, a detachable connection or setting, or an integral connection or setting; they can refer to a direct connection or an indirect connection. Those skilled in the art can understand the specific meaning of the above terms in this patent according to the specific circumstances.

[0035] Please see Figures 1-9 The diagram shows the structure of an embodiment provided by this utility model.

[0036] This embodiment provides a special threaded joint for oil well pipes suitable for use in harsh environments, including a pipe 1, a hydraulic impact relief joint 2, and a coupling 3;

[0037] Both ends of the pipe 1 are symmetrically provided with external thread structure I11 on their outer circumferential surfaces; the external thread structure I11 includes an external thread 111, an external sealing cylindrical shoulder 112, an external cylindrical surface 113, an external sealing arc 114, an external sealing stop slope 115, and an internal boring hole 116 arranged sequentially from the middle to the end face; the external thread 111 is a tapered pipe thread;

[0038] The inner circumferential surfaces at both ends of the coupling 3 are symmetrically provided with internal thread structure I 31; the internal thread structure I 31 includes an internal thread 311, an inner cylindrical surface 312, an inner sealing conical surface 313, an inner arc 314, and an inner sealing stop inclined surface 315 arranged sequentially from the end face to the middle; the internal thread 311 is a tapered pipe thread used in conjunction with the external thread 111.

[0039] The left end of the hydraulic impact relief connector 2 is provided with an internal thread structure II 32 connected to one end of the pipe 1, and the right end is provided with an external thread structure II 12 connected to one end of the coupling 3. An impact positioning block 21 is provided on the outer circumference of the connector, and a hydraulic impact relief assembly 22 is provided inside. The internal thread structure II 32 is the same as the internal thread structure I 31, and the external thread structure II 12 is the same as the external thread structure I 11.

[0040] When rotating and meshing, the external thread 111 is screwed into the corresponding internal thread 311. The external sealing cylindrical shoulder 112, the external sealing arc 114, and the external sealing stop slope 115 of the external thread 111 gradually come into contact with the inner cylindrical surface 312, the inner sealing conical surface 313, and the inner sealing stop slope 315 of the internal thread structure I 31 until an interference fit is achieved.

[0041] The number of impact positioning blocks 21 is 4 to 6.

[0042] The hydraulic impact relief assembly 22 includes an upper valve core 211, a spring 214, a lower valve sleeve 215, and a positioning snap ring 216 for limiting the lower valve sleeve, arranged sequentially from left to right. The upper valve core 211 has 4 to 6 radial through holes 2111 on its outer circumference at its small end. Each impact positioning block 21 has a cylindrical through hole 213. The small end of the upper valve core 211 is inserted into the cavity of the lower valve sleeve 215 and slidably connected. The spring 214 is connected between the upper valve core 211 and the lower valve sleeve 215. During operation, the radial through holes 2111 communicate with the cylindrical through holes 213.

[0043] It should be noted that this utility model adopts a hydraulic impact relief valve design. Under low to medium pressure conditions, due to the support of the spring, the radial through hole and the cylindrical through hole are connected, and the mud is sprayed out from the cylindrical through hole, spraying onto the well wall to remove irregularities or obstructions. During subsequent cementing, under high pressure, the upper valve core moves downward to the lower valve sleeve, compressing the spring and simultaneously blocking the radial through hole, preventing the mud from spraying out from the cylindrical through hole. The mud then passes normally through the hydraulic impact relief valve for cementing. This significantly reduces the risk of jamming in harsh environments such as irregular well diameters, areas prone to shrinkage, and areas prone to blockage, greatly improving safety and reliability under complex conditions.

[0044] It should be noted that this utility model adopts a metal arc surface interference fit design with a metal sealing cone surface to ensure sealing performance under complex well conditions such as high-angle wells, horizontal wells, and large doglegs.

[0045] It should be noted that both the upper valve core 211 and the lower valve sleeve 215 have grooves 212 on their outer circumferences, and the grooves are filled with O-rings for sealing, which improves the sealing effect.

[0046] The upper valve core 211 and the lower valve sleeve 215 are made of aluminum alloy.

[0047] Wherein, the guide angle B of the external thread 111 and the internal thread 311 is 25°, and the bearing surface angle A is -5°.

[0048] Wherein, the outer diameter of the pipe 1 is D = 60.32~339.7mm, the outer cylindrical surface diameter D1 = the inner cylindrical surface diameter D2, and the inner boring diameter d1 = the coupling inner diameter D3.

[0049] It should be noted that this utility model adopts an internal parallel design where the male thread inner boring hole is consistent with the inner diameter of the coupling, avoiding the influence of turbulence, ensuring quality while greatly improving the efficiency of subsequent hydraulic construction.

[0050] Specifically, when the outer diameter of pipe 1 is D = 60.32~73.02mm, the thread pitch P = 3.18mm; when the outer diameter is D = 88.9~114.3mm, the thread pitch P = 4.23mm; and when the outer diameter is D = 127.00~339.7mm, the thread pitch P = 5.08mm.

[0051] Wherein, the outer diameter of the impact positioning block D3 > the outer diameter of the coupling D2 > the outer diameter of the specification D.

[0052] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A special threaded joint for oil well pipes suitable for use in harsh environments, characterized in that: It includes pipe (1), hydraulic impact relief joint (2), and coupling (3); The outer circumferential surfaces of both ends of the pipe (1) are symmetrically provided with external thread structure I (11); the external thread structure I (11) includes an external thread (111), an outer sealing cylindrical shoulder (112), an outer cylindrical surface (113), an outer sealing arc (114), an outer sealing stop slope (115), and an inner boring hole (116) arranged sequentially from the middle to the end face; the external thread (111) is a tapered pipe thread; The inner circumferential surfaces of both ends of the coupling (3) are symmetrically provided with internal thread structure I (31); the internal thread structure I (31) includes an internal thread (311), an inner cylindrical surface (312), an inner sealing conical surface (313), an inner arc (314), and an inner sealing stop inclined surface (315) arranged sequentially from the end face to the middle; the internal thread (311) is a tapered pipe thread used in conjunction with the external thread (111); The left end of the hydraulic impact relief connector (2) is provided with an internal thread structure II (32) connected to one end of the pipe (1), and the right end is provided with an external thread structure II (12) connected to one end of the coupling (3). An impact positioning block (21) is provided on the outer circumference of the connector, and a hydraulic impact relief assembly (22) is provided inside. The internal thread structure II (32) is consistent with the internal thread structure I (31), and the external thread structure II (12) is consistent with the external thread structure I (11). When rotating and meshing, the external thread (111) is screwed into the corresponding internal thread (311). The external sealing cylindrical shoulder (112), external sealing arc (114), and external sealing stop slope (115) of the external thread (111) gradually come into contact with the inner cylindrical surface (312), inner sealing conical surface (313), and inner sealing stop slope (315) of the internal thread structure I (31) until an interference fit is achieved. The guide angle B of the external thread (111) and the internal thread (311) is 25°, and the bearing surface angle A is -5°. The hydraulic impact relief assembly (22) includes an upper valve core (211), a spring (214), a lower valve sleeve (215), and a positioning snap ring (216) arranged sequentially from left to right. The upper valve core (211) has 4 to 6 radial through holes (2111) on the outer circumference of its small end. The impact positioning block (21) has a cylindrical through hole (213). The small end of the upper valve core (211) is inserted into the cavity of the lower valve sleeve (215) and slidably connected. The spring (214) is connected between the upper valve core (211) and the lower valve sleeve (215). During operation, the radial through holes (2111) and the cylindrical through holes (213) are connected.

2. The special threaded joint for oil well pipes suitable for use in harsh environments according to claim 1, characterized in that: The number of impact positioning blocks (21) is 4 to 6.

3. The special threaded joint for oil well pipes suitable for use in harsh environments according to claim 1, characterized in that: The upper valve core (211) and the lower valve sleeve (215) are both provided with grooves (212) on their outer circumferences, and the grooves are filled with O-ring seals for sealing.

4. A special threaded joint for oil well pipes suitable for use in harsh environments according to claim 3, characterized in that: The upper valve core (211) and lower valve sleeve (215) are made of aluminum alloy.

5. A special threaded joint for oil well pipes suitable for use in harsh environments according to claim 4, characterized in that: The outer diameter (D) of the tube (1) is 60.32 to 339.7 mm, the outer cylindrical surface diameter (D1) is equal to the inner cylindrical surface diameter (d2), and the inner boring diameter (d1) is equal to the inner diameter of the coupling (d3).

6. A special threaded joint for oil well pipes suitable for use in harsh environments according to claim 5, characterized in that: When the outer diameter (D) of the pipe (1) is 60.32 to 73.02 mm, the thread pitch (P) is 3.18 mm; when the outer diameter (D) is 88.9 to 114.3 mm, the thread pitch (P) is 4.23 mm; when the outer diameter (D) is 127.00 to 339.7 mm, the thread pitch (P) is 5.08 mm.

7. A special threaded joint for oil well pipes suitable for use in harsh environments according to claim 6, characterized in that: The outer diameter of the impact positioning block (D3) is greater than the outer diameter of the coupling (D2) and the outer diameter of the specification (D).

Images