CN215256080U

CN215256080U - Direct-connection fracturing pipe for small well and large discharge capacity

Info

Publication number: CN215256080U
Application number: CN202120547240.9U
Authority: CN
Inventors: 钱山红
Original assignee: Wuxi Beilai Tubes Co ltd
Current assignee: Wuxi Beilai Tubes Co ltd
Priority date: 2021-03-16
Filing date: 2021-03-16
Publication date: 2021-12-21
Anticipated expiration: 2031-03-16

Abstract

The utility model relates to the technical field of oil well pipelines, especially, relate to a slim hole, straight connecting pipe for fracturing that big discharge was used, it includes the pipe main part, pipe main part one end is equipped with the box conical head, and the other end is equipped with the pin conical head, the box conical head includes first seal segment, female connection section and the second seal segment that sets gradually to intraductal by the mouth of pipe, first seal segment, female connection section and second seal segment three integrated into one piece, the tip of first seal segment is triangle-shaped along the cross-section of pipe main part axis, and the juncture of second seal segment inner wall and pipe main part inner wall forms first step face; the male buckle conical head comprises a third sealing section, an external thread connecting section and a fourth sealing section which are sequentially arranged from the pipe opening to the pipe, the third sealing section, the external thread connecting section and the fourth sealing section are integrally formed, and an annular groove is formed at the junction of the fourth sealing section and the pipe main body. The utility model discloses have the effect that connection sealing performance is good.

Description

Direct-connection fracturing pipe for small well and large discharge capacity

Technical Field

The utility model belongs to the technical field of the technique of oil well pipeline and specifically relates to a pipe is used in the straight joint fracturing that slim hole, big displacement were used.

Background

With increasingly harsh drilling conditions of oil wells and gas wells, API 5B round threads and buttress threads cannot meet the existing practical requirements.

To API screwed joint, no matter be round thread form or buttress thread form, the back is screwed up to the joint, can produce certain fit clearance between the inside and outside screw thread, and this clearance is the heliciform, can communicate sheathed tube inside and outside space, the fluidic leakage passage of stroke, only rely on the screw thread fat to fill, the API screw thread just can play sealed effect. However, the thread grease is easy to volatilize and deteriorate, and especially when the downhole temperature is higher, the volatilization and deterioration are faster, the effect of blocking a leakage channel is obviously reduced, and when the pressure of fluid, especially gas, in the joint is higher, the API joint is easy to have a leakage accident.

The conventional common oil pipe at present has the following defects:

(1) the coupling connection is adopted, so that the working condition of the slim hole cannot be used;

(2) the API thread does not have air seal, and the working condition with high pressure is easy to leak;

(3) the pipe body material uses API standard performance material, and cracking accident easily occurs in the fracturing working condition.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a pipe is used in the straight joint fracturing that slim hole, big discharge capacity were used, it has the effect that sealing performance is good to exist not enough to prior art.

The above object of the present invention is achieved by the following technical solutions:

a direct-connection fracturing pipe for a small borehole and large discharge capacity, which comprises a pipe main body, wherein one end of the pipe main body is provided with a female buckle conical head, the other end is provided with a male buckle conical head,

the female buckle conical head comprises a first sealing section, an internal thread connecting section and a second sealing section which are sequentially arranged from a pipe orifice to the inside of the pipe, the first sealing section, the internal thread connecting section and the second sealing section are integrally formed, the section of the end head part of the first sealing section along the axial line of the pipe body is triangular, and a first step surface is formed at the junction of the inner wall of the second sealing section and the inner wall of the pipe body;

the male buckle conical head comprises a third sealing section, an external thread connecting section and a fourth sealing section which are sequentially arranged from a pipe orifice to the inside of the pipe, the third sealing section, the external thread connecting section and the fourth sealing section are integrally formed, an annular groove is formed at the junction of the fourth sealing section and the pipe main body,

the end of the first sealing section is inserted into the annular groove of the fourth sealing section to form a sealing structure, the internal thread connecting section is in threaded connection with the external thread connecting section, and the end face of the third sealing section abuts against the first step face of the second sealing section to form a sealing structure.

The present invention may be further configured in a preferred embodiment as: the inner diameter of the internal thread connecting section is gradually reduced from the pipe orifice to the direction in the pipe;

the outer diameter of the external thread connecting section is gradually increased from the pipe orifice to the pipe inner direction.

The present invention may be further configured in a preferred embodiment as: the top end of the end head of the first sealing section is arc-shaped, and the bottom wall of the annular groove of the fourth sealing section is arc-shaped.

The present invention may be further configured in a preferred embodiment as: the internal corner of the junction of the second sealing section and the pipe main body is arc-shaped, and the external corner of the third sealing section is arc-shaped.

The present invention may be further configured in a preferred embodiment as: the guide angle of the internal thread section is 25 degrees, and the bearing angle of the internal thread section is-3.5 degrees.

The present invention may be further configured in a preferred embodiment as: the guide angle of the external thread section is 25 degrees, and the bearing angle of the external thread section is-3.5 degrees.

To sum up, the utility model discloses a following at least one useful technological effect:

1. the direct connection type structure is adopted, and the device can be used for the working condition of a slim hole;

2. the thread adopts an improved buttress thread, the bearing angle is-3 degrees, the barb shape is realized, and the connection strength is high;

3. the main seal adopts a female button conical surface/a male button conical surface, and is double-seal, so that the sealing effect is good;

4. the guide angle is 25 degrees, the button insertion is easy, and the button staggering is not easy.

5. By adopting a specific process, the service performance of the pipe body is 20% higher than that of an API (application program interface) common product.

Drawings

FIG. 1 is a schematic diagram of a background art configuration;

FIG. 2 is a schematic view of the overall structure of a direct-connection fracturing pipe in the embodiment;

FIG. 3 is a sectional view of the female screw connecting section in the embodiment

FIG. 4 is a cross-sectional view of the male screw connecting section in the example

Fig. 5 is a schematic diagram of two directly connected fracturing tubulars in an example embodiment.

In the figure, 1, a tube main body; 2. a female button conical head; 21. a first seal section; 22. an internal threaded connection section; 23. a second seal section; 3. a male button conical head; 31. a third seal section; 32. an external thread connecting section; 33. a fourth seal section; 331. an annular groove; 4. a coupling; 5. and (4) an oil pipe.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

Example (b):

referring to fig. 2-5, for the utility model discloses a pipe is used in the straight link fracturing that slim hole, big discharge capacity used, including pipe main part 1, pipe main part 1 one end is equipped with box awl head 2, and the other end is equipped with pin thread awl head 3.

Female knot conical head 2 includes by the mouth of pipe to intraductal first seal segment 21, female connection section 22 and the second seal segment 23 that sets gradually, first seal segment 21, female connection section 22 and the 23 three integrated into one piece of second seal segment, and the end portion of first seal segment 21 is triangle-shaped along the cross-section of 1 axis of pipe main part, and the juncture of the 23 inner walls of second seal segment and 1 inner wall of pipe main part forms first step face.

The male-buckle conical head 3 comprises a third sealing section 31, an external thread connecting section 32 and a fourth sealing section 33 which are sequentially arranged in a pipe from the pipe opening to the pipe, the third sealing section 31, the external thread connecting section 32 and the fourth sealing section 33 are integrally formed, and an annular groove 331 is formed at the junction of the fourth sealing section 33 and the pipe main body 1.

When two adjacent pipes for direct connection fracturing are assembled together, the female buckle conical head 2 on one pipe for direct connection fracturing is assembled with the male buckle conical head 3 of the other pipe for direct connection fracturing, the end of the first sealing section 21 is inserted into the annular groove 331 of the fourth sealing section 33 to form a sealing structure, the internal thread connecting section 22 is in threaded connection with the external thread connecting section 32, the end face of the third sealing section 31 abuts against the first step face of the second sealing section 23 to form a sealing structure, and the two pipes for direct connection fracturing are assembled together in this way.

Wherein, the internal diameter of female connection section 22 is reduced gradually to intraductal direction by the mouth of pipe, and the external diameter of male connection section 32 is crescent to intraductal direction by the mouth of pipe, reinforcing threaded connection section's sealed effect.

The top end of the first sealing section 21 is arc-shaped, the bottom wall of the annular groove 331 of the fourth sealing section 33 is arc-shaped, and during assembly, the arc-shaped end of the first sealing section 21 is inserted into the annular groove 331 of the fourth sealing section 33, so that the sealing effect of the first sealing section 21 and the second sealing section 23 is better.

The internal corner of the interface of the second sealing section 23 and the pipe main body 1 is arc-shaped, and the external corner of the third sealing section 31 is arc-shaped, so that the sealing effect between the second sealing section 23 and the third sealing section 31 is further enhanced.

The guiding angle of the internal thread section is 25 degrees, the bearing angle of the internal thread section is-3.5 degrees, the guiding angle of the external thread connecting section 32 is 25 degrees, and the bearing angle of the external thread connecting section 32 is-3.5 degrees.

The guide angle refers to an included angle between the thread guide surface and the vertical direction, and the bearing angle refers to an included angle between the thread bearing surface and the vertical direction.

The thread adopts the improved buttress thread, the bearing angle is-3 degrees, the barb shape is presented, the connection strength is high, the guide angle is 25 degrees, the button insertion is easy, and the staggered button is not easy.

The embodiment of this specific implementation mode is the preferred embodiment of the present invention, not limit according to this the utility model discloses a protection scope, so: all equivalent changes made according to the structure, shape and principle of the utility model are covered within the protection scope of the utility model.

Claims

1. A small hole, large displacement used directly connecting the fracturing and using the tube, characterized by that: comprises a pipe main body (1), one end of the pipe main body (1) is provided with a female buckle conical head (2), the other end is provided with a male buckle conical head (3),

the female buckle conical head (2) comprises a first sealing section (21), an internal thread connecting section (22) and a second sealing section (23) which are sequentially arranged from a pipe opening to the inside of the pipe, the first sealing section (21), the internal thread connecting section (22) and the second sealing section (23) are integrally formed, the cross section of the end head part of the first sealing section (21) along the axis of the pipe main body (1) is triangular, and a first step surface is formed at the junction of the inner wall of the second sealing section (23) and the inner wall of the pipe main body (1);

the male buckle conical head (3) comprises a third sealing section (31), an external thread connecting section (32) and a fourth sealing section (33) which are sequentially arranged from the pipe opening to the pipe, the third sealing section (31), the external thread connecting section (32) and the fourth sealing section (33) are integrally formed, an annular groove (331) is formed at the junction of the fourth sealing section (33) and the pipe main body (1),

the end of the first sealing section (21) is inserted into an annular groove (331) of the fourth sealing section (33) to form a sealing structure, the internal thread connecting section (22) is in threaded connection with the external thread connecting section (32), and the end face of the third sealing section (31) abuts against a first step face of the second sealing section (23) to form a sealing structure.

2. A slim hole, high displacement, straight connection frac tubing of claim 1, wherein: the inner diameter of the internal thread connecting section (22) is gradually reduced from the pipe orifice to the pipe inner direction;

the outer diameter of the external thread connecting section (32) is gradually increased from the pipe orifice to the pipe inner direction.

3. A slim hole, high displacement, straight connection frac tubing of claim 1, wherein: the top end of the end head of the first sealing section (21) is arranged to be arc-shaped, and the bottom wall of the annular groove (331) of the fourth sealing section (33) is arranged to be arc-shaped.

4. A slim hole, high displacement, straight connection frac tubing of claim 1, wherein: the internal corner of the junction of the second sealing section (23) and the pipe main body (1) is arc-shaped, and the external corner of the third sealing section (31) is arc-shaped.

5. A slim hole, high displacement, straight connection frac tubing of claim 1, wherein: the guide angle of the internal thread connecting section (22) is 25 degrees, and the bearing angle of the internal thread connecting section (22) is-3.5 degrees.

6. A slim hole, high displacement, straight connection frac tubing of claim 2, wherein: the guide angle of the external thread connecting section (32) is 25 degrees, and the bearing angle of the external thread connecting section (32) is-3.5 degrees.