CN218934346U - Flexible drilling tool nipple joint and flexible drilling tool - Google Patents
Flexible drilling tool nipple joint and flexible drilling tool Download PDFInfo
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- CN218934346U CN218934346U CN202223480446.8U CN202223480446U CN218934346U CN 218934346 U CN218934346 U CN 218934346U CN 202223480446 U CN202223480446 U CN 202223480446U CN 218934346 U CN218934346 U CN 218934346U
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Abstract
The utility model provides a flexible drilling tool nipple and a flexible drilling tool, wherein the flexible drilling tool nipple comprises a ball seat and a ball head, one end of the ball head is a spherical body, a ball socket for inserting the spherical body is arranged on the ball seat, a spherical groove is arranged on the side wall of the spherical body, a mounting hole which is opposite to the spherical groove is arranged on the side wall of the ball socket, a pressing cap for preventing the spherical part in the mounting hole from sliding out and the spherical body from being separated from the ball socket is sleeved on the outer side of the ball seat, and the pressing cap is in threaded connection with the outer wall of the ball seat. The flexible drilling tool nipple provided by the utility model effectively solves the technical problem that the stability of the side wall of the pressing cap and the side wall of the ball socket is poor due to the fact that the side wall of the pressing cap and the ball socket are fixed through the pin in the prior art.
Description
Technical Field
The utility model relates to a flexible drilling tool nipple joint and a flexible drilling tool, and belongs to the technical field of underground drilling tools.
Background
In the development process of the oil and gas well, in order to perfect the injection and production relation and improve the utilization degree of residual oil, the old well sidetrack is often drilled by using the original shaft, and the conventional drilling tool is characterized by small curvature, large radius and overlong deflecting section, and long-section deflecting drilling is required when the drilling is carried out on a target horizon. However, when drilling a horizontal well with a large curvature and a short radius, the flexible drilling tool is critical, and particularly in a slim hole drilled at the side of an old well, the flexible drilling tool is flexible to rotate, reliable in sealing, capable of bearing larger torque and high in design difficulty.
At present, in the chinese patent of the utility model with the date of the grant 2018.03.30 and the number of the grant CN 207161005U, a flexible drill rod is provided, which comprises a ball seat and a ball head, one end of the ball head is a ball body, one end of the ball seat is provided with a ball socket for the ball body to be inserted, the ball body and the ball socket are matched to realize flexible rotation of the flexible drill rod, for realizing torque transmission, the side wall of the ball body is provided with an external spline, the side wall of the ball socket is provided with an internal spline matched with the external spline, and a cavity required by the ball head swing is arranged between the external spline and the internal spline, in addition, for preventing the ball body from falling out from the opening of the ball socket, the opening of the ball socket is provided with a pressing cap, and the pressing cap is fixed with the side wall of the ball socket through a screw.
Although the flexible drill rod can meet the use requirement, the flexible drill rod has some problems in the use process, specifically: 1. the flexible drill rod is matched with the external spline on the ball body and the internal spline on the ball socket to realize torque transmission, and the structure can limit the rotation amplitude of the flexible drilling tool and reduce the flexibility of the flexible drill rod; 2. because the flexible drilling tool needs to transmit larger torque in the drilling process, the screw between the pressing cap and the ball socket needs to bear larger shearing force, and the phenomenon that the ball seat and the ball head are separated due to the breakage of the screw easily occurs after the flexible drilling tool is used for a period of time. In order to solve the problems of small rotation amplitude and poor flexibility of the flexible drill rod, the Chinese patent utility model with the authority notice date of 2011.11.23 and the authority notice number of CN 202047748U provides an ultra-short radius horizontal well flexible drilling tool, which comprises an upper joint, a lower joint, a bending shell and a plurality of flexible drill rod units, wherein each flexible drill rod unit comprises a ball seat and a ball head, one end of each ball head is a ball body, one end of each ball seat is provided with a ball socket for the insertion of the corresponding ball body, the ball body is matched with the ball socket to realize flexible rotation of the flexible drill rod, a spherical groove is formed in the side wall of each ball body to realize torque transmission, a mounting hole which is opposite to the spherical groove is formed in the side wall of each ball socket, a steel ball is mounted in the mounting hole, one part of the steel ball is positioned in the spherical groove, torque transmission is realized between the steel ball and the ball body, a pressing cap is sleeved outside the ball seat and the ball body in the ball socket, and the ball body is prevented from sliding out of the ball socket, and the pressing cap is fixed with the outer side of the ball socket through a pin.
The flexible drilling tool can solve the problems of small rotation amplitude and poor flexibility of the drilling tool, but the side walls of the pressing cap and the ball socket are still fixed through the pin, so that the phenomenon that the ball seat and the ball head are easy to separate after being used for a period of time still exists.
Disclosure of Invention
The utility model aims to provide a flexible drilling tool nipple to solve the technical problem that in the prior art, stability is poor due to the fact that a pressing cap and the side wall of a ball socket are fixed through a pin. Meanwhile, the utility model also provides a flexible drilling tool for solving the problems.
The flexible drilling tool nipple adopts the following technical scheme:
the flexible drilling tool nipple comprises a ball seat and a ball head, wherein one end of the ball head is a ball body, a ball socket for the insertion of the ball body is arranged on the ball seat, a spherical groove is arranged on the side wall of the ball body, a mounting hole which is opposite to the spherical groove is arranged on the side wall of the ball socket, a pressing cap for preventing the ball part in the mounting hole from sliding out and the ball body from falling out of the ball socket is sleeved on the outer side of the ball seat, and the pressing cap is in threaded connection with the outer wall of the ball seat.
The beneficial effects are that: the utility model provides a novel flexible drilling tool nipple after improvement of the existing flexible drilling tool, when the novel flexible drilling tool nipple is assembled, firstly, the spherical body on the ball head is inserted into the ball socket on the ball seat, the spherical groove on the spherical body is adjusted to be opposite to the mounting hole on the ball socket, then, the spherical part is installed in the mounting hole, one part of the spherical part is positioned in the mounting hole, the other part of the spherical part is positioned in the spherical groove, torque transmission between the ball head and the ball seat is realized, and then, the press cap is sleeved on the outer side of the ball seat and is in threaded connection with the outer wall of the ball seat, so that the spherical part in the mounting hole is prevented from sliding out and the spherical body is prevented from falling out of the ball socket.
Further, the mounting hole is an inclined hole extending obliquely along the axial direction of the flexible drilling tool nipple.
The beneficial effects are that: when the spherical part is installed in the installation hole, the installation hole is an inclined hole, so that the spherical part can be prevented from sliding out of the installation hole before the cap is pressed in the installation process, the flexible drilling tool nipple is convenient to assemble, and the assembly efficiency is improved.
Further, the inner wall surface of the mounting hole, which is close to one side of the spherical groove, is matched with the outer circumferential surface of the spherical member.
The beneficial effects are that: the arrangement can reduce the movable space of the spherical element when transmitting torque, thereby being beneficial to improving the torque transmission effect.
Further, an annular step is arranged on the ball seat, and the width of the annular step is equal to the wall thickness of the press cap in the radial direction of the flexible drilling tool nipple.
The beneficial effects are that: the arrangement can enable the outer peripheral surface of the ball seat to be flush with the press cap when the press cap is sleeved on the ball seat, so that the resistance of the drilling tool during drilling is reduced.
Further, one of the ball head and the ball seat is integrally arranged on the upper joint of the flexible drilling tool nipple, and the other is integrally arranged on the lower joint of the flexible drilling tool nipple.
The beneficial effects are that: the number of the short section parts of the flexible drilling tool can be reduced by the arrangement, and the flexible drilling tool is convenient to process and assemble.
Further, the spherical grooves are arranged at intervals of at least two in the circumferential direction of the spherical body.
The beneficial effects are that: this arrangement can improve the torque transmission effect.
Further, a first sealing structure is arranged between the press cap and the spherical body.
The beneficial effects are that: the sealing performance of the flexible drilling tool nipple can be improved through the arrangement.
Further, the first sealing structure comprises a sealing groove arranged on the spherical body and a sealing ring arranged in the sealing groove.
The beneficial effects are that: simple structure, convenient processing.
Further, a second sealing structure is arranged between the pressing cap and the ball seat.
The beneficial effects are that: the sealing performance of the flexible drilling tool nipple can be improved through the arrangement.
The flexible drilling tool adopts the following technical scheme:
the flexible drilling tool comprises at least two connected flexible drilling tool pup joints, the flexible drilling tool pup joints comprise ball seats and ball heads, one ends of the ball heads are ball bodies, ball seats are provided with ball sockets for the insertion of the ball bodies, the side walls of the ball bodies are provided with spherical grooves, the side walls of the ball sockets are provided with mounting holes which are opposite to the spherical grooves, the outer side of each ball seat is sleeved with a pressing cap for preventing the ball parts in the mounting holes from sliding out and the ball bodies from being separated from the ball sockets, and the pressing caps are in threaded connection with the outer walls of the ball seats.
The beneficial effects are that: the utility model provides a new flexible drilling tool aiming at the improvement of the existing flexible drilling tool, when the new flexible drilling tool is assembled, firstly, the spherical body on the ball head is inserted into the ball socket on the ball seat, the spherical groove on the spherical body is adjusted to be opposite to the mounting hole on the ball socket, then, the spherical part is arranged in the mounting hole, one part of the spherical part is positioned in the mounting hole, the other part of the spherical part is positioned in the spherical groove, the torque transmission between the ball head and the ball seat is realized, and then, the press cap is sleeved on the outer side of the ball seat and is in threaded connection with the outer wall of the ball seat, so that the spherical part in the mounting hole is prevented from sliding out and the spherical body is prevented from falling out of the ball socket.
Further, the mounting hole is an inclined hole extending obliquely along the axial direction of the flexible drilling tool nipple.
The beneficial effects are that: when the spherical part is installed in the installation hole, the installation hole is an inclined hole, so that the spherical part can be prevented from sliding out of the installation hole before the cap is pressed in the installation process, the flexible drilling tool nipple is convenient to assemble, and the assembly efficiency is improved.
Further, the inner wall surface of the mounting hole, which is close to one side of the spherical groove, is matched with the outer circumferential surface of the spherical member.
The beneficial effects are that: the arrangement can reduce the movable space of the spherical element when transmitting torque, thereby being beneficial to improving the torque transmission effect.
Further, an annular step is arranged on the ball seat, and the width of the annular step is equal to the wall thickness of the press cap in the radial direction of the flexible drilling tool nipple.
The beneficial effects are that: the arrangement can enable the outer peripheral surface of the ball seat to be flush with the press cap when the press cap is sleeved on the ball seat, so that the resistance of the drilling tool during drilling is reduced.
Further, one of the ball head and the ball seat is integrally arranged on the upper joint of the flexible drilling tool nipple, and the other is integrally arranged on the lower joint of the flexible drilling tool nipple.
The beneficial effects are that: the number of the short section parts of the flexible drilling tool can be reduced by the arrangement, and the flexible drilling tool is convenient to process and assemble.
Further, the spherical grooves are arranged at intervals of at least two in the circumferential direction of the spherical body.
The beneficial effects are that: this arrangement can improve the torque transmission effect.
Further, a first sealing structure is arranged between the press cap and the spherical body.
The beneficial effects are that: the sealing performance of the flexible drilling tool nipple can be improved through the arrangement.
Further, the first sealing structure comprises a sealing groove arranged on the spherical body and a sealing ring arranged in the sealing groove.
The beneficial effects are that: simple structure, convenient processing.
Further, a second sealing structure is arranged between the pressing cap and the ball seat.
The beneficial effects are that: the sealing performance of the flexible drilling tool nipple can be improved through the arrangement.
Drawings
FIG. 1 is a semi-sectional view of embodiment 1 of the flexible drilling tool sub of the present utility model;
FIG. 2 is a cross-sectional view taken at F-F in FIG. 1;
fig. 3 is a schematic view of the connection of two flexible drilling tool subs of fig. 1.
The names of the corresponding components in the figures are:
100. an upper joint; 101. a lower joint; 102. ball head; 103. a ball seat; 104. a spherical body; 105. a ball socket; 106. a spherical member; 107. a first sealing structure; 108. a second sealing structure; 109. sealing ring grooves; 110. a hollow channel; 111. pressing the cap; 112. a threaded section; 113. a threaded hole; 114. a mounting hole; 115. spherical grooves.
Detailed Description
The present utility model is described in further detail below with reference to examples.
Embodiment 1 of the flexible drilling tool of the present utility model:
as shown in fig. 1 and 2, the flexible drilling tool for a plurality of flexible drilling tool sub provided in this embodiment includes an upper joint 100 and a lower joint 101, a ball head 102 is provided on the upper joint 100, a ball seat 103 is provided on the lower joint 101, one end of the ball head 102 is a ball body 104, a ball socket 105 for inserting the ball body 104 is provided on the ball seat 103, a spherical groove 115 is provided on a side wall of the ball body 104, a mounting hole 114 for being arranged opposite to the spherical groove 115 is provided on a side wall of the ball socket 105, a ball member 106 is mounted in the mounting hole 114, one part of the ball member 106 is located in the mounting hole 114, the other part is located in the spherical groove 115, a pressing cap 111 is sleeved outside the ball seat 103 to prevent the ball member 106 in the mounting hole 114 from sliding out and the ball body 104 from the ball socket 105, and in order to ensure stability of the pressing cap 111, and a threaded connection is provided between the pressing cap 111 and an outer wall of the ball seat 103.
In this embodiment, as shown in fig. 1 and 2, the mounting hole 114 is an inclined hole extending obliquely in the axial direction of the flexible drill for facilitating the mounting of the ball member 106. In addition, in order to secure the torque transmission effect, two spherical grooves 115 are arranged at intervals in the circumferential direction of the spherical body 104, and accordingly, the number of the mounting holes 114 is also two, and the inner wall surface of the mounting hole 114 on the side close to the spherical groove 115 is fitted with the outer peripheral surface of the spherical member 106.
In this embodiment, to reduce the number of parts of the flexible drilling tool, the upper joint 100 is integrally provided with the ball head 102, and the lower joint 101 is integrally provided with the ball seat 103. In addition, in order to enhance the sealing effect, as shown in fig. 1, a first sealing structure 107 is provided between the press cap 111 and the spherical body 104, and the first sealing structure 107 includes a sealing groove provided on the spherical body 104 and a sealing ring provided in the sealing groove. A second sealing structure 108 is arranged between the press cap 111 and the ball seat 103, and the second sealing structure 108 comprises a sealing groove arranged on the ball seat 103 and a sealing ring arranged in the sealing groove.
In this embodiment, as shown in fig. 3, the number of the flexible drilling tool short sections can be adjusted according to actual situations, and when in use, the plurality of flexible drilling tool short sections are sequentially connected to the required length from head to tail, for this purpose, the upper joint 100 is provided with a threaded section 112, and the lower joint 101 is provided with a threaded hole 113 adapted to the threaded section 112. In order to improve the sealing performance, as shown in fig. 1, a seal ring groove 109 is provided at an end of the upper joint 100, and a seal ring is installed in the seal ring groove 109. The centers of the upper joint 100 and the lower joint 101 are provided with hollow passages 110 penetrating from top to bottom.
In this embodiment, the ball seat 103 is provided with an annular step, and the width of the annular step is equal to the wall thickness of the press cap 111 in the radial direction of the flexible drill nipple.
In this embodiment, the use process of the flexible drilling tool is as follows: firstly, in the sidetracking process of windowing of an old well in an oil field, a whipstock is arranged below a windowing point to perform sidetracking of windowing; connecting the flexible drilling tool short sections, and after successful windowing, sequentially connecting the upper joint 100 and the lower joint 101 of each flexible drilling tool short section in a threaded manner; then, deflecting and drilling, namely deflecting by using a deflecting drill bit, a flexible drilling tool pup joint and a conventional drill rod, and deflecting to form a certain trend; sequentially reversely buckling out the flexible drilling tool nipple connected with the screw thread to a wellhead; then drilling steadily, sequentially lowering a gauge protection drill bit, a flexible drilling tool pup joint and a conventional drilling tool into a wellhead, sequentially connecting the gauge protection drill bit, the flexible drilling tool pup joint and the conventional drilling tool in a threaded manner until the wellhead is reached, circulating slurry through the hollow channel 110, and drilling steadily; and finally, after drilling to a target layer in a stable way, sequentially and reversely buckling a flexible drilling tool connected with the screw thread to a wellhead.
Example 2 of the flexible drilling tool of the present utility model:
the present embodiment is different from embodiment 1 in that in embodiment 1, the second seal structure includes a seal groove provided on the ball seat and a seal ring provided in the seal groove. In this embodiment, the second sealing structure includes a gasket.
Example 3 of the flexible drilling tool of the present utility model:
the present embodiment is different from embodiment 1 in that in embodiment 1, a second sealing structure is provided between the press cap and the ball seat. In this embodiment, a sealing structure is not disposed between the pressing cap and the ball seat.
Example 4 of the flexible drilling tool of the present utility model:
the present embodiment is different from embodiment 1 in that in embodiment 1, the first seal structure includes a seal groove provided on the ball seat and a seal ring provided in the seal groove. In this embodiment, the first sealing structure includes a gasket.
Example 5 of the flexible drilling tool of the present utility model:
the present embodiment is different from embodiment 1 in that in embodiment 1, a first sealing structure is provided between the press cap and the spherical body. In this embodiment, a sealing structure is not disposed between the press cap and the spherical body.
Example 6 of the flexible drilling tool of the present utility model:
this embodiment is different from embodiment 1 in that in embodiment 1, spherical grooves are arranged two by two at intervals in the circumferential direction of the spherical body. In the present embodiment, however, the spherical grooves are arranged three at intervals in the circumferential direction of the spherical body. Of course, it is also possible for only one spherical recess to be arranged in the circumferential direction of the spherical body.
Example 7 of the flexible drilling tool of the present utility model:
the present embodiment is different from embodiment 1 in that in embodiment 1, the upper joint is integrally provided with the ball head, and the lower joint is integrally provided with the ball seat. In this embodiment, the upper joint is separately disposed from the ball head, and the lower joint is separately disposed from the ball seat.
Example 8 of the flexible drilling tool of the present utility model:
this embodiment differs from embodiment 1 in that in embodiment 1, a ball head is provided on an upper joint, and a ball seat is provided on a lower joint. In this embodiment, the ball seat is disposed on the upper joint, and the ball head is disposed on the lower joint.
Example 9 of the flexible drilling tool of the present utility model:
the present embodiment is different from embodiment 1 in that in embodiment 1, the inner wall surface of the mounting hole on the side close to the spherical recess is fitted to the outer peripheral surface of the spherical member. In this embodiment, the inner wall surface of the mounting hole on the side close to the spherical groove is a cylindrical surface.
Embodiment 10 of the flexible drilling tool of the present utility model:
the present embodiment is different from embodiment 1 in that in embodiment 1, the mounting hole is an inclined hole extending obliquely in the axial direction of the flexible drilling tool. In this embodiment, the mounting hole is a horizontal hole extending in the radial direction of the flexible drilling tool.
Embodiments of flexible drilling tool subs in the present utility model:
the structure of the flexible drilling tool nipple provided by the embodiment is the same as that of the flexible drilling tool nipple in any embodiment of the flexible drilling tool.
The above description is only a preferred embodiment of the present utility model, and the patent protection scope of the present utility model is defined by the claims, and all equivalent structural changes made by the specification and the drawings of the present utility model should be included in the protection scope of the present utility model.
Claims (10)
1. The utility model provides a flexible drilling tool nipple joint, includes ball seat and bulb, and the one end of bulb is the spheroid, is provided with on the ball seat and is used for supplying the male ball socket of spheroid, is provided with spherical recess on the lateral wall of spheroid, is equipped with on the lateral wall of ball socket to be used for just arranging the mounting hole with spherical recess, and the outside cover of ball seat is equipped with the pressure cap that is used for preventing the ball in the mounting hole roll-off and the spheroid deviate from the ball socket, its characterized in that, is threaded connection between the outer wall of pressure cap and ball seat.
2. The flexible drilling tool sub of claim 1, wherein the mounting hole is a beveled hole extending obliquely in an axial direction of the flexible drilling tool sub.
3. The flexible drilling tool nipple of claim 1, wherein an inner wall surface of the mounting hole on a side adjacent to the spherical recess is adapted to mate with an outer peripheral surface of the spherical member.
4. A flexible drilling tool sub according to claim 1, 2 or 3, wherein the ball seat is provided with an annular step, the width of which is equal to the wall thickness of the press cap in the radial direction of the flexible drilling tool sub.
5. A flexible drilling tool sub according to claim 1, 2 or 3, wherein one of the ball and ball seat is integrally provided on the upper joint of the flexible drilling tool sub and the other is integrally provided on the lower joint of the flexible drilling tool sub.
6. A flexible drilling tool sub according to claim 1, 2 or 3, wherein the spherical grooves are spaced apart at least two in the circumferential direction of the spherical body.
7. A flexible drilling tool sub according to claim 1, 2 or 3, wherein a first sealing arrangement is provided between the press cap and the ball.
8. The flexible drilling tool sub of claim 7, wherein the first sealing structure comprises a sealing groove disposed on the bulb and a sealing ring disposed in the sealing groove.
9. A flexible drilling tool sub according to claim 1, 2 or 3, wherein a second sealing arrangement is provided between the press cap and the ball seat.
10. A flexible drilling tool comprising at least two connected flexible drilling tool subs, wherein the flexible drilling tool subs are as claimed in any one of claims 1 to 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202223480446.8U CN218934346U (en) | 2022-12-26 | 2022-12-26 | Flexible drilling tool nipple joint and flexible drilling tool |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202223480446.8U CN218934346U (en) | 2022-12-26 | 2022-12-26 | Flexible drilling tool nipple joint and flexible drilling tool |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN218934346U true CN218934346U (en) | 2023-04-28 |
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ID=86084801
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202223480446.8U Active CN218934346U (en) | 2022-12-26 | 2022-12-26 | Flexible drilling tool nipple joint and flexible drilling tool |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN218934346U (en) |
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2022
- 2022-12-26 CN CN202223480446.8U patent/CN218934346U/en active Active
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