CN215632825U

CN215632825U - Casing threaded joint for rotary well cementation

Info

Publication number: CN215632825U
Application number: CN202122285462.0U
Authority: CN
Inventors: 罗李强; 罗日新; 何宏
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-09-18
Filing date: 2021-09-18
Publication date: 2022-01-25
Anticipated expiration: 2031-09-18

Abstract

The utility model relates to a casing threaded joint for rotary well cementation, which comprises a pipe and a coupling, wherein the pipe and the coupling have a common axis, two ends of the pipe are subjected to necking treatment, and an external thread, an external sealing conical surface, a pin thread inclined shoulder and a pin thread inclined end surface are processed on the outer wall after necking; the coupling is arranged along the middle surface in a bilateral symmetry mode, and internal threads, a combined sealing surface, a first female-buckle inclined shoulder and a second female-buckle inclined shoulder are machined at two ends of the coupling. The threaded joint of the casing for rotary well cementation has high thread strength and strong torsion resistance by adopting the design of coarse threads; by arranging the two reverse torque shoulders, the torsion resistance and the compression resistance of the joint can be further improved, and the effect of strong torsion resistance is achieved; by adopting the unique metal/metal sealing structure, the joint still can keep better sealing performance under the action of high torque, high compression and impact load, and the integral sealing performance can be effectively improved.

Description

Casing threaded joint for rotary well cementation

Technical Field

The utility model relates to the technical field of petroleum pipe threaded joints, in particular to a threaded joint of a casing pipe for rotary well cementation.

Background

In the Tarim basin and the Sichuan basin, abundant natural gas resources are buried, but the natural gas in the blocks is deep in buried depth, high in pressure, complex in stratum, large in abrasion resistance of a sleeve pipe under the site, more in sections when meeting resistance, and special conditions of rotating the sleeve pipe, strongly twisting the sleeve pipe, strongly pressing the sleeve pipe to construct and the like often occur, so that the situation requires that the pipe joint of the fort has higher torsion resistance, compression resistance and impact resistance, and better sealing performance must be kept at the same time.

At present, an API joint is generally adopted by an oil casing pipe, the sealing performance is improved, meanwhile, the torsion resistance is also improved due to the addition of a torque shoulder, and the disadvantage is that the thread pitch of a thread is small, the thread is easy to damage when the torque is larger, and meanwhile, due to the design of a single torque shoulder, the torsion resistance of the torque shoulder is limited, so that the torsion resistance of the joint is not improved to a large extent, and the social requirement cannot be met, and therefore, the threaded joint of the casing pipe for rotary well cementation is provided to solve the problems.

SUMMERY OF THE UTILITY MODEL

Aiming at the defects of the prior art, the utility model provides the casing threaded joint for rotary cementing, which has the advantages of strong torsion resistance and the like, and solves the problems that the casing threaded joint has limited torsion resistance and the thread is easy to damage when the torsion is large.

In order to achieve the purpose of strong torsion resistance, the utility model provides the following technical scheme: a kind of rotary well cementation uses the threaded joint of the quill, including pipe and coupling, said pipe and coupling have common axis, both ends of said pipe are reduced and processed, there are external screw thread, external sealing conical surface, male button sloping shoulder and male button sloping terminal surface on the outer wall after reducing the mouth;

the coupling is arranged along the middle surface in a bilateral symmetry mode, and internal threads, a combined sealing surface, a first female-buckle inclined shoulder and a second female-buckle inclined shoulder are machined at two ends of the coupling.

Further, the external thread and the internal thread are both coarse threads, the thread pitch of the external thread and the internal thread is 7.257m, the thread guide face angle theta is 10-15 degrees, the bearing face angle beta is 3-5 degrees, the internal thread tooth height h1 is 1.80-2.05m, and the external thread tooth height h2 is hl-0.1 mm.

Further, the tail part of the external thread is provided with an external sealing conical surface, and the taper of the external sealing conical surface is 1: 2; and a combined sealing surface is arranged at the corresponding position of the tail part of the internal thread, the combined sealing surface is composed of a transition arc, a guide arc and a section of conical surface with the length of about 1.0mm, and the taper of the conical surface is 1: 2.

Furthermore, the radii of the transition arc and the guide arc are the same and are both 18-20mm, the transition arc and the guide arc are both tangent to the conical surface, the circle centers of the transition arc and the guide arc are located on the same side of the conical surface, and the distance between the circle centers of the transition arc and the guide arc is 1.0 mm.

Further, a pin thread inclined shoulder and a pin thread inclined end face are arranged on one side of the outer sealing conical surface, the axial distance between the pin thread inclined shoulder and the pin thread inclined end face is 5-9mm, and the inclination angles of the pin thread inclined shoulder and the pin thread inclined end face are both a degrees equal to 9 degrees; and a first female-buckle inclined shoulder and a second female-buckle inclined shoulder are arranged on one side of the combined sealing surface, and the inclination angles of the first female-buckle inclined shoulder and the second female-buckle inclined shoulder are both a and 9 degrees.

Further, the two ends of the pipe are subjected to necking treatment, the inner diameter d1 after necking is 1.0-1.5mm smaller than the inner diameter d of the pipe, namely d1 is d- (1-1.5) mm, the necking length is 2.0-8.0mm, and the inner diameter d2 of the coupling is the same as the inner diameter d 1.

Furthermore, the external thread and the internal thread are in radial interference fit, and the interference magnitude is 0.12-0.32 mm; the outer sealing conical surface is in radial interference fit with the combined sealing surface, and the interference magnitude is 0.46-0.88 mm; the inclined shoulder of the male buckle is in axial interference fit with the first inclined shoulder of the female buckle, the inclined end face of the male buckle is in axial interference fit with the second inclined shoulder of the female buckle, and the interference magnitude is 0.07-0.25mm, so that a whole is formed.

Compared with the prior art, the utility model provides a casing threaded joint for rotary cementing, which has the following beneficial effects:

the threaded joint of the casing for rotary well cementation has high thread strength and strong torsion resistance by adopting the design of coarse threads; by arranging the two reverse torque shoulders, the torsion resistance and the compression resistance of the joint can be further improved, and the effect of strong torsion resistance is achieved; by adopting the unique metal/metal sealing structure, the joint still can keep better sealing performance under the action of high torque and high compression and impact load, the integral sealing performance can be effectively improved, and the problems that the sleeve threaded joint has limited torsion resistance and the threads are easy to damage when the torque is large are solved.

Drawings

FIG. 1 is a cross-sectional view of the structure of the present invention;

FIG. 2 is a schematic structural view of the internal thread of the present invention;

FIG. 3 is a schematic view of the construction of the external threads of the present invention;

FIG. 4 is a schematic view of the structure of the shoulder of the present invention.

In the figure: the pipe comprises a pipe 1, an external thread 2, an external sealing conical surface 3, a male thread inclined shoulder 4, a male thread inclined end surface 5, a coupling 6, an internal thread 7, an combined sealing surface 8, a female thread first inclined shoulder 9, a female thread second inclined shoulder 10, a coupling middle surface 11, an axis 12, a transition arc 13, a conical surface 14 and a guide arc 15.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1-4, a casing threaded joint for rotary cementing comprises a pipe 1 and a coupling 6, wherein the pipe 1 and the coupling 6 share a common axis 12, two ends of the pipe 1 are subjected to necking treatment, and an external thread 2, an external sealing conical surface 3, a pin thread inclined shoulder 4 and a pin thread inclined end surface 5 are processed on the outer wall after necking;

the coupling 6 is arranged along the middle surface 11 in bilateral symmetry, the two ends of the coupling 6 are provided with internal threads 7, a combined sealing surface 8, a first female-buckle sloping shoulder 9 and a second female-buckle sloping shoulder 10, the two ends of the pipe 1 are subjected to necking treatment, the inner diameter d1 after necking is 1.0-1.5mm smaller than the inner diameter d of the pipe, the length of the necking is 2.0-8.0mm, the two ends of the pipe 1 are subjected to necking treatment, the purpose is to increase the thickness of the shoulders, after the joint is screwed down, the inner diameters d2 and d1 of the coupling 6 are the same, and natural gas flows more smoothly in the pipe without generating turbulence.

Referring to fig. 2-3, in the present embodiment, the external thread 2 and the internal thread 7 are both coarse threads, the thread pitch of the external thread 2 and the internal thread 7 is 7.257m, the thread guide surface angle θ is 10-15 °, the bearing surface angle β is 3-5 °, the thread height h1 of the internal thread 7 is 1.80-2.05m, the thread height h2 of the external thread 2 is hl-0.1mm, the thread height of the internal thread 7 is higher than that of the external thread 2, and after the internal thread 7 is engaged with the external thread 2, a certain gap is formed between the tooth crest of the external thread 2 and the tooth bottom of the internal thread 7, so as to provide a sufficient storage space for the thread teeth.

Referring to fig. 4, in the present embodiment, the tail portion of the external thread 2 is provided with an external sealing conical surface 3, and the taper of the external sealing conical surface 3 is 1: 2; the corresponding position of the tail of the internal thread 7 is provided with a combined sealing surface 8, the combined sealing surface 8 is provided with a transition arc 13, a guide arc 15 and a section of conical surface 14 with the length of about 1.0mm, the taper of the conical surface 14 is 1:2, and the transition arc 13 and the guide arc 15 are arranged to mainly play a guide role, so that the conical surface 14 can be in smooth transition when being in tight screwing fit with the external sealing conical surface 3.

The radii of the transition arc 13 and the guide arc 15 are the same and are both 18-20mm, the transition arc 13 and the guide arc 15 are tangent to the conical surface 14, the centers of the transition arc 13 and the guide arc 15 are located on the same side of the conical surface 14, and the distance between the centers of the transition arc 13 and the guide arc 15 is 1.0 mm.

One side of the outer sealing conical surface 3 is provided with a pin thread inclined shoulder 4 and a pin thread inclined end surface 5, the axial distance between the pin thread inclined shoulder 4 and the pin thread inclined end surface 5 is 5-9mm, and the inclination angles of the pin thread inclined shoulder 4 and the pin thread inclined end surface 5 are both a degrees of 9 degrees; one side of the combined sealing surface 8 is provided with a first inclined shoulder 9 of the female thread and a second inclined shoulder 10 of the female thread, and the inclination angles of the first inclined shoulder 9 of the female thread and the second inclined shoulder 10 of the female thread are respectively 9 degrees.

The external thread 2 and the internal thread 7 are in interference fit in the radial direction, and the interference magnitude is 0.12-0.32 mm; the outer sealing conical surface 3 is in radial interference fit with the combined sealing surface 8, and the interference magnitude is 0.46-0.88 mm; the inclined shoulder 4 of the male buckle is in axial interference fit with the first inclined shoulder 9 of the female buckle, the inclined end surface 5 of the male buckle is in axial interference fit with the second inclined shoulder 10 of the female buckle, and the interference magnitude is 0.07-0.25mm, so that a whole is formed.

The beneficial effects of the above embodiment are as follows:

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the utility model, the scope of which is defined in the appended claims and their equivalents.

Claims

1. A casing nipple for rotary cementing comprising a pipe (1) and a coupling (6), said pipe (1) and coupling (6) having a common axis (12), characterized in that: necking the two ends of the pipe (1), and processing an external thread (2), an external sealing conical surface (3), a pin thread inclined shoulder (4) and a pin thread inclined end surface (5) on the outer wall after necking;

the coupling (6) is arranged along the middle surface (11) in a bilateral symmetry mode, and internal threads (7), a combined sealing surface (8), a first female-thread oblique shoulder (9) and a second female-thread oblique shoulder (10) are machined at two ends of the coupling (6).

2. A casing nipple for rotary cementing according to claim 1, wherein: the external thread (2) and the internal thread (7) are both provided with coarse threads, the thread pitch of the external thread (2) and the thread pitch of the internal thread (7) are 7.257m, the thread guide face angle theta is 10-15 degrees, the bearing face angle beta is 3-5 degrees, the tooth height h1 of the internal thread (7) is 1.80-2.05m, and the tooth height h2 of the external thread (2) is hl-0.1 mm.

3. A casing nipple for rotary cementing according to claim 1, wherein: the tail part of the external thread (2) is provided with an external sealing conical surface (3), and the taper of the external sealing conical surface (3) is 1: 2; a combined sealing surface (8) is arranged at a corresponding position of the tail of the internal thread (7), the combined sealing surface (8) is provided with a transition arc (13), a guide arc (15) and a section of conical surface (14) with the length of about 1.0mm, and the taper of the conical surface (14) is 1: 2.

4. A casing nipple for rotary cementing according to claim 3, wherein: the radius of the transition arc (13) is the same as that of the guide arc (15), the transition arc (13) and the guide arc (15) are both 18-20mm, the transition arc (13) and the guide arc (15) are tangent to the conical surface (14), the circle centers of the transition arc (13) and the guide arc (15) are located on the same side of the conical surface (14), and the distance between the circle centers of the transition arc (13) and the guide arc (15) is 1.0 mm.

5. A casing nipple for rotary cementing according to claim 1, wherein: a pin thread inclined shoulder (4) and a pin thread inclined end face (5) are arranged on one side of the outer sealing conical surface (3), the axial distance between the pin thread inclined shoulder (4) and the pin thread inclined end face (5) is 5-9mm, and the inclination angles of the pin thread inclined shoulder (4) and the pin thread inclined end face (5) are both a-9 degrees; and a first female-buckle inclined shoulder (9) and a second female-buckle inclined shoulder (10) are arranged on one side of the combined sealing surface (8), and the inclination angles of the first female-buckle inclined shoulder (9) and the second female-buckle inclined shoulder (10) are respectively 9 degrees.

6. A casing nipple for rotary cementing according to claim 1, wherein: the two ends of the pipe (1) are subjected to necking treatment, the inner diameter d1 after necking is 1.0-1.5mm smaller than the inner diameter d of the pipe, namely d1 is d- (1-1.5) mm, the necking length is 2.0-8.0mm, and the inner diameter d2 of the coupling (6) is the same as the inner diameter d 1.

7. A casing nipple for rotary cementing according to claim 1, wherein: the external thread (2) and the internal thread (7) are in radial interference fit, and the interference magnitude is 0.12-0.32 mm; the outer sealing conical surface (3) is in radial interference fit with the combined sealing surface (8), and the interference magnitude is 0.46-0.88 mm; the male buckle oblique shoulder (4) is in axial interference fit with the female buckle first oblique shoulder (9), the male buckle oblique end face (5) is in axial interference fit with the female buckle second oblique shoulder (10), and the interference magnitude is 0.07-0.25mm, so that a whole is formed.