CN210918913U - High-torsion-resistance air-tight seal oil casing threaded joint - Google Patents
High-torsion-resistance air-tight seal oil casing threaded joint Download PDFInfo
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- CN210918913U CN210918913U CN201921430104.0U CN201921430104U CN210918913U CN 210918913 U CN210918913 U CN 210918913U CN 201921430104 U CN201921430104 U CN 201921430104U CN 210918913 U CN210918913 U CN 210918913U
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Abstract
The utility model relates to a high antitorque gas seal oil casing screwed joint, include coupling and first body, the second body through threaded connection, its characterized in that: the middle part of the inner wall of the coupling is provided with an annular coupling inner circular bead cylindrical surface, sawtooth-shaped internal threads with a negative bearing face angle are processed at the two ends of the coupling, an internal thread circular bead and a sealing combination structure are arranged at the tail end of the sawtooth-shaped internal threads close to the coupling inner circular bead cylindrical surface, the end parts of the first pipe body and the second pipe body corresponding to the internal thread circular bead and the sealing combination structure are subjected to necking treatment, sawtooth-shaped external threads with a negative bearing face angle are formed on the outer walls of the pipe ends of the first pipe body and the second pipe body after the necking treatment, and an external thread circular bead and a sealing combination structure are arranged at the tail end of the. The utility model discloses not only strengthened the joint strength and the bending resistance performance that connect, made the joint have good airtight ability moreover, still had good torsional strength simultaneously.
Description
Technical Field
The utility model relates to a be applied to oil well pipe screwed joint of oil industry, specifically speaking are high antitorque gas seal oil casing screwed joint.
Background
Oil casings in the oil well pipe industry are mainly connected through threaded joints to form oil casing strings, wherein the requirements on the aspects of the strength index, the sealing performance, the torque resistance and the like of the threaded joint connection are high.
The joints currently used for oil casings are generally API joints. The API joint is mature in technology and good in interchangeability, but is poor in sealing performance, particularly poor in air sealing performance, and cannot meet the exploitation requirement of a natural gas well, and meanwhile, the torsion resistance is not ideal, and accidents caused by damage due to overlarge torque often occur.
Due to the defects of the API joints, oil well pipe companies or oil fields are gradually seeking special threaded connection structures with better performance and reliability.
SUMMERY OF THE UTILITY MODEL
The utility model aims to overcome the aforesaid not enough, provide joint strength height, air-tight seal performance is good, has a high anti-torque gas seal oil casing screwed joint of higher anti-torque strength simultaneously.
The purpose of the utility model is realized like this:
a high anti-torsion gas-tight sealing oil casing threaded joint comprises a coupling, a first pipe body and a second pipe body which are connected through threads, wherein the coupling, the first pipe body and the second pipe body have a common axis, the middle part of the inner wall of the coupling is provided with an annular inner circular bead cylindrical surface of the coupling, two ends of the coupling are processed with sawtooth-shaped internal threads with a bearing surface angle being a negative angle, the tail end of the sawtooth-shaped internal threads close to the cylindrical surface of the inner circular bead of the coupling are provided with an internal thread circular bead and a sealing combined structure, the internal thread circular bead and the sealing combined structure comprise an internal thread auxiliary circular bead, an internal thread main circular bead and an internal sealing conical surface, and the internal sealing conical; the middle part of the inner sealing conical surface is provided with an inner sealing spherical surface;
the end parts of the first pipe body and the second pipe body corresponding to the internal thread shoulder and the sealing combination structure are processed through necking, a sawtooth-shaped external thread with a bearing surface angle being a negative angle is formed on the outer walls of the pipe ends of the first pipe body and the second pipe body after the necking processing, the tail end of the sawtooth-shaped external thread is close to the end face and is provided with the external thread shoulder and the sealing combination structure, the external thread shoulder and the sealing combination structure comprise an external thread main shoulder, an external thread auxiliary shoulder and an external sealing conical surface, and the external thread main shoulder and the external sealing conical surface are connected through a transition cylindrical surface.
Furthermore, the inclination angle of the main shoulder of the external thread on the first pipe body and the inclination angle of the main shoulder of the internal thread on the second pipe body are the same, the thickness of the main shoulder of the external thread is the same as that of the main shoulder of the internal thread, the inclination angle of the auxiliary shoulder of the external thread is the same as that of the auxiliary shoulder of the internal thread, and the thickness of the auxiliary shoulder of the external thread is the same as that of the auxiliary shoulder of the internal thread.
Furthermore, the inner diameter of the pipe body after necking is reduced by 1.5-2.5 mm compared with that of a normal pipe, the length of the necking is 15-20 mm, and the transition angle between the inner wall of the necking and the inner wall of the pipe body is not more than 7 degrees.
Further, the radius of the inner sealing spherical surface is 45-55 mm, the taper of the inner sealing conical surface is 1:10, and the inner sealing conical surface is divided into two sections by the inner sealing spherical surface; the taper of the outer sealing conical surface is 1:10, and the outer sealing conical surface is connected with the external thread main shoulder through the transition cylindrical surface.
Furthermore, the total length of an internal thread combined sealing surface formed by the internal sealing spherical surface and the internal sealing conical surface is 10-12 mm, and the total length of an external thread combined sealing surface formed by the external sealing conical surface and the transition cylindrical surface is the same as that of the internal thread combined sealing surface.
Furthermore, the thread bearing face angle of the sawtooth-shaped internal thread and the sawtooth-shaped external thread is 3-5 degrees, the guide face angle is 10-25 degrees, the inclination directions are consistent, and the threads are in a sawtooth shape.
Further, the taper 9 of the sawtooth-shaped internal thread and the sawtooth-shaped external thread is 1: 16, the thread pitch is 5.08mm, the width of the tooth-shaped groove is 1.27-2.54 mm, the tooth-shaped tooth width is 0.03-0.05 mm smaller than the groove width, two ends of the tooth-shaped tooth are provided with tooth-shaped circular arcs, the radius of the tooth-shaped circular arcs is 0.20-0.76 mm, the tooth height of the sawtooth-shaped internal thread is 1.22-1.78 mm, and the tooth height of the sawtooth-shaped external thread is 0.2-0.3 mm smaller than that of the sawtooth-shaped internal.
Furthermore, the length range of the inner shoulder cylindrical surface of the coupling is 25.4-50.8 mm.
Furthermore, the inclination angle of the internal thread main shoulder is 5-8 degrees, the thickness of the internal thread main shoulder is 3.0-3.5 mm, the inclination angle of the internal thread auxiliary shoulder is 3-5 degrees, and the thickness of the internal thread auxiliary shoulder is 3.5-4.5 mm.
Compared with the prior art, the beneficial effects of the utility model are that:
the utility model relates to a high antitorque gas seal oil casing screwed joint has adopted zigzag screw thread to add two reverse torque circular bead and has added the sealed structural style of metal/metal, has not only strengthened the joint strength and the bending resistance performance that connect, makes the joint have good airtight ability moreover, still has good torsional strength simultaneously.
Drawings
Fig. 1 is a schematic structural diagram of the high-torsion-resistance gas-tight oil casing threaded joint of the present invention.
Fig. 2 is an exploded view of fig. 1.
Fig. 3 is a thread pattern diagram of the internal thread of the high-torsion-resistance gas-tight oil casing threaded joint of the present invention.
Fig. 4 is a thread profile of the external thread of the high anti-torque gas-tight oil casing threaded joint of the present invention.
Fig. 5 is a schematic view of the internal thread shoulder and the sealing combination structure of the high-torsion-resistance gas-tight sealing oil casing threaded joint of the present invention.
Fig. 6 is the schematic view of the external thread shoulder and the seal combination structure of the high anti-torque gas-tight oil casing threaded joint of the present invention.
Wherein:
the coupling comprises a coupling 1, a first pipe body 2, a sawtooth internal thread 3, a sawtooth external thread 4, an internal thread shoulder and sealing combined structure 5, an external thread shoulder and sealing combined structure 6, a coupling internal shoulder cylindrical surface 7, a medium diameter line 8, a taper 9, a thread pitch 10, a tooth-shaped groove width 11, a tooth-shaped tooth width 12, a sawtooth internal thread tooth height 13, a bearing surface angle 14, a guide surface angle 15, a tooth-shaped circular arc 16, a sawtooth external thread tooth height 17, an external thread main shoulder 18, an internal thread main shoulder 19, an external thread auxiliary shoulder 20, an internal thread auxiliary shoulder 21, an external sealing conical surface 22, an internal sealing spherical surface 23, a transition cylindrical surface 24, an internal sealing conical surface 25, an external thread main shoulder inclined angle 26, an internal thread main shoulder inclined angle 27, an external thread auxiliary shoulder inclined angle 28, an internal thread auxiliary shoulder inclined angle 29, an external thread combined sealing surface total length 30, A transition bevel inclination 33, a second tube 34, and an axis 35.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.
Please refer to fig. 1-6, the utility model discloses a high antitorque airtight oil casing screwed joint, it is PT-HTC specific at my department's product model, a high antitorque airtight oil casing screwed joint includes coupling 1 and first body 2 through threaded connection, second body 34, coupling 1, first body 2, second body 34 possess common axis 35, coupling 1 and first body 2, second body 34 are with virtual medium diameter line 8 as the benchmark, interior, the external screw thread closes soon, carry out a plurality of connections through coupling 1 with second body 34 with first body 2, form oil, the casing string, satisfy oil and gas field production operation requirement.
The middle part of the inner wall of the coupling 1 is provided with an annular coupling inner circular bead cylindrical surface 7, the length range of the coupling inner circular bead cylindrical surface 7 is 25.4-50.8 mm, the purpose is to form a circular bead, and the first pipe body 2, the second pipe body 34 and the coupling have the same inner diameter, so that fluid in the pipe body can smoothly flow.
Two ends of a coupling 1 are processed with sawtooth-shaped internal threads 3 with a negative bearing surface angle, an internal thread shoulder and sealing combined structure 5 is arranged at the tail end of each sawtooth-shaped internal thread 3 close to a cylindrical surface 7 of an internal shoulder of the coupling, each internal thread shoulder and sealing combined structure 5 comprises an internal thread auxiliary shoulder 21, an internal thread main shoulder 19 and an internal sealing conical surface 25, and the internal sealing conical surface 25 connects the internal thread auxiliary shoulder 21 with the internal thread main shoulder 19. The middle part of the inner sealing conical surface 25 is provided with an inner sealing spherical surface 23. The inclination angle 27 of the internal thread main shoulder 19 is 5-8 degrees, the thickness of the internal thread main shoulder 19 is 3.0-3.5 mm, the inclination angle 29 of the internal thread auxiliary shoulder 21 is 3-5 degrees, and the thickness of the internal thread auxiliary shoulder 21 is 3.5-4.5 mm;
the end parts of the first pipe body 2 and the second pipe body 34 corresponding to the internal thread shoulder and the sealing combined structure 5 are subjected to necking treatment, the inner diameter of the necking is reduced by 1.5-2.5 mm compared with that of a normal pipe, the necking length 32 is 15-20 mm, the transition angle 33 between the inner wall of the necking and the inner wall of the pipe body is not more than 7 degrees, a saw-tooth-shaped external thread 4 with a negative bearing surface angle is formed on the outer wall of the pipe end of the first pipe body 2 and the outer wall of the pipe end of the second pipe body 34 after the necking treatment, the external thread shoulder and the sealing combined structure 6 are arranged at the position close to the end face of the saw-tooth-shaped external thread 4, the external thread shoulder and the sealing combined structure 6 comprise an external thread main shoulder 18, an external thread auxiliary shoulder 20 and an external sealing. The inclination angle 26 of the main shoulder of the external thread on the first pipe body 2 and the inclination angle 27 of the main shoulder of the internal thread on the second pipe body 34 are the same, the thickness of the main shoulder of the external thread 18 is the same as that of the main shoulder of the internal thread 19, the inclination angle 28 of the auxiliary shoulder of the external thread is the same as that of the inclination angle 29 of the auxiliary shoulder of the internal thread, and the thickness of the auxiliary shoulder of the external thread 20 is the same as that of the auxiliary.
The radius of the inner sealing spherical surface 23 is 45-55 mm, the taper of the inner sealing conical surface 25 is 1:10, and the inner sealing conical surface 25 is divided into two sections by the inner sealing spherical surface 23; the taper of the outer sealing conical surface 22 is 1:10, and the outer sealing conical surface is connected with the external thread main shoulder 18 through a transition cylindrical surface 24. The total length 31 of the internal thread combined sealing surface formed by the internal sealing spherical surface 23 and the internal sealing conical surface 25 is 10-12 mm, and the total length 30 of the external thread combined sealing surface formed by the external sealing conical surface 22 and the transition cylindrical surface 24 is the same as the total length 31 of the internal thread combined sealing surface.
As shown in fig. 3 and 4, the thread bearing face angle 14 of the internal zigzag thread 3 and the external zigzag thread 4 is 3 ° to 5 °, the guide face angle 15 is 10 ° to 25 °, the inclination directions are the same, and the threads are zigzag. The conicity 9 of the sawtooth-shaped internal thread 3 and the sawtooth-shaped external thread 4 is 1: 16, the thread pitch 10 is 5.08mm, the taper and the thread pitch are the same as those of the API buttress thread, the width 11 of a tooth-shaped groove is 1.27-2.54 mm, the width 12 of the tooth-shaped tooth is 0.03-0.05 mm smaller than the groove width, two ends of the tooth-shaped tooth are provided with tooth-shaped arcs 16, the radius of the tooth-shaped arcs 16 is 0.20-0.76 mm, the height 13 of a sawtooth-shaped internal thread of the sawtooth-shaped internal thread 3 is 1.22-1.78 mm, and the height 17 of a sawtooth-shaped external thread of the sawtooth-shaped external thread 4 is 0.2-0.3 mm smaller than the height 13. When the zigzag threads are subjected to axial tensile load, radial component force cannot be generated, so that the connection strength is high, and the bending resistance is strong. Meanwhile, the tooth height of the sawtooth-shaped internal thread is slightly larger than that of the sawtooth-shaped external thread, so that a certain amount of thread grease is stored in a thread gap, the lubricating performance between threads is improved, and the threads are not easy to damage.
The utility model discloses during the operation, on the first body 2 of the first body of arbitrary one end screw in of coupling 1 or second body 34, should detain the internal thread of coupling 1 and the first body 2 of the first body of external screw in 3 ~ 7 earlier of second body 34 during the screw in, with the internal and external screw thread left-hand thread right-hand thread then manpower screw in to when the manpower is closed soon, will have had the tight screwing up coupling 1 together of hand and first body 2 or second body 34 to further screw up the interference fit state with the screw-on machine.
In the screwing process, the sawtooth-shaped external thread 4 and the sawtooth-shaped internal thread 3 firstly form a radial interference fit state, the internal thread main shoulder 19 and the external thread main shoulder 18 start to contact and generate axial interference fit to share screwing torque, the main shoulder elastically deforms along with further screwing, the internal thread auxiliary shoulder 21 and the external thread auxiliary shoulder 20 start to contact and generate axial interference fit to share redundant torque. When a certain torque is reached, the joint is in a screwing state, the inner sealing spherical surface 23 on the coupling 1 and the outer sealing conical surface 22 on the first pipe body 2 or the second pipe body 34 are in radial interference fit, and high contact pressure is formed on the contact surfaces, so that the sealing effect is achieved.
The utility model arranges sawtooth type screw thread on the inner wall of the coupling 1 and the end parts of the first pipe body 2 and the second pipe body 34, which increases the connection strength and the bending resistance of the joint; the anti-torque shoulder and the metal/metal sealing structure are added between the pipe end and the coupling, so that the anti-torque performance and the air sealing performance of the joint are further improved; and the pipe end is subjected to necking treatment, so that the thickness of the shoulder is increased, and the torsion resistance of the joint is further improved.
The utility model discloses processing is simple and convenient, and application range is wide, and safe and reliable can bear higher gas pressure and twist reverse load and do not leak or damage, can satisfy the operation requirement in oil field.
The above is only a specific application example of the present invention, and does not constitute any limitation to the protection scope of the present invention. All the technical solutions formed by equivalent transformation or equivalent replacement fall within the protection scope of the present invention.
Claims (9)
1. The utility model provides a high antitorque gas seal oil casing screwed joint, includes coupling and first body, the second body through threaded connection, and coupling, first body, second body possess common axis, its characterized in that:
the middle part of the inner wall of the coupling is provided with an annular coupling inner shoulder cylindrical surface, two ends of the coupling are processed with sawtooth-shaped internal threads with a negative bearing surface angle, the tail end of the sawtooth-shaped internal threads close to the coupling inner shoulder cylindrical surface are provided with an internal thread shoulder and sealing combined structure, the internal thread shoulder and sealing combined structure comprises an internal thread auxiliary shoulder, an internal thread main shoulder and an internal sealing conical surface, and the internal sealing conical surface connects the internal thread auxiliary shoulder and the internal thread main shoulder; the middle part of the inner sealing conical surface is provided with an inner sealing spherical surface;
the end parts of the first pipe body and the second pipe body corresponding to the internal thread shoulder and the sealing combination structure are processed through necking, a sawtooth-shaped external thread with a bearing surface angle being a negative angle is formed on the outer walls of the pipe ends of the first pipe body and the second pipe body after the necking processing, the tail end of the sawtooth-shaped external thread is close to the end face and is provided with the external thread shoulder and the sealing combination structure, the external thread shoulder and the sealing combination structure comprise an external thread main shoulder, an external thread auxiliary shoulder and an external sealing conical surface, and the external thread main shoulder and the external sealing conical surface are connected through a transition cylindrical surface.
2. The highly anti-torque gas-tight oil casing threaded joint according to claim 1, wherein the inclination angle of the main shoulder of the male thread on the first pipe body and the inclination angle of the main shoulder of the female thread on the second pipe body are the same, the thickness of the main shoulder of the male thread is the same as that of the main shoulder of the female thread, the inclination angle of the sub shoulder of the male thread is the same as that of the sub shoulder of the female thread, and the thickness of the sub shoulder of the male thread is the same as that of the sub shoulder of the female thread.
3. The high-torsion-resistance air-tight oil casing threaded joint according to claim 1, wherein the internal diameter after necking is reduced by 1.5-2.5 mm compared with that of a normal pipe, the length of the necking is 15-20 mm, and the transition angle between the inner wall of the necking and the inner wall of the pipe body is not more than 7 °.
4. The high-torsion-resistance air-tight seal oil sleeve threaded joint as claimed in claim 1, wherein the radius of the inner seal spherical surface is 45-55 mm, the taper of the inner seal conical surface is 1:10, and the inner seal conical surface is divided into two sections by the inner seal spherical surface; the taper of the outer sealing conical surface is 1:10, and the outer sealing conical surface is connected with the external thread main shoulder through the transition cylindrical surface.
5. The threaded joint of the oil casing with the high torsional gas resistance as claimed in claim 1, wherein the total length of the internal thread combined sealing surface formed by the internal sealing spherical surface and the internal sealing conical surface is 10-12 mm, and the total length of the external thread combined sealing surface formed by the external sealing conical surface and the transition cylindrical surface is the same as that of the internal thread combined sealing surface.
6. The threaded joint for oil casing with high anti-torque gas sealing according to claim 1, wherein the thread bearing face angle of the internal serrated thread and the external serrated thread has a value of 3 ° to 5 °, the guide face angle has a value of 10 ° to 25 °, and the inclination directions are identical so that the threads are serrated.
7. The threaded joint for oil casing with high torsional gas tightness according to claim 1, wherein the taper of the internal serrated thread and the external serrated thread is 1: 16, the thread pitch is 5.08mm, the width of the tooth-shaped groove is 1.27-2.54 mm, the tooth-shaped tooth width is 0.03-0.05 mm smaller than the groove width, two ends of the tooth-shaped tooth are provided with tooth-shaped circular arcs, the radius of the tooth-shaped circular arcs is 0.20-0.76 mm, the tooth height of the sawtooth-shaped internal thread is 1.22-1.78 mm, and the tooth height of the sawtooth-shaped external thread is 0.2-0.3 mm smaller than that of the sawtooth-shaped internal.
8. The threaded joint for oil casing with high torsional gas tightness according to claim 1, wherein the length of the inner shoulder cylindrical surface of the coupling ranges from 25.4 mm to 50.8 mm.
9. The high-torsion-resistance air-tight seal oil sleeve threaded joint as claimed in claim 1, wherein the inclination angle of the internal thread main shoulder is 5-8 °, the thickness of the internal thread main shoulder is 3.0-3.5 mm, the inclination angle of the internal thread auxiliary shoulder is 3-5 °, and the thickness of the internal thread auxiliary shoulder is 3.5-4.5 mm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921430104.0U CN210918913U (en) | 2019-08-30 | 2019-08-30 | High-torsion-resistance air-tight seal oil casing threaded joint |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921430104.0U CN210918913U (en) | 2019-08-30 | 2019-08-30 | High-torsion-resistance air-tight seal oil casing threaded joint |
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| CN210918913U true CN210918913U (en) | 2020-07-03 |
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| CN201921430104.0U Active CN210918913U (en) | 2019-08-30 | 2019-08-30 | High-torsion-resistance air-tight seal oil casing threaded joint |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110529055A (en) * | 2019-08-30 | 2019-12-03 | 江苏璞腾油气装备有限公司 | A kind of high antitorque air-tight oil casing nipple |
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2019
- 2019-08-30 CN CN201921430104.0U patent/CN210918913U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110529055A (en) * | 2019-08-30 | 2019-12-03 | 江苏璞腾油气装备有限公司 | A kind of high antitorque air-tight oil casing nipple |
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