CN111894476A - Steel joint titanium alloy pipe body threaded connection type light drill rod - Google Patents

Abstract

The invention provides a steel joint titanium alloy pipe body threaded connection type light drill rod, wherein two ends of a joint A are both internal threads, a sealing shoulder A is arranged in one end of the joint A, and a transition shoulder A and an interference assembly shoulder A are arranged at the end part of the joint A; one end of the joint B is an external thread, the other end of the joint B is an internal thread, a sealing shoulder B is arranged in one end of the joint B, and a transition shoulder B and an interference assembly shoulder B are arranged at the end part of the joint B; sealing shoulder surfaces are arranged on the end surfaces of the two ends of the pipe body, and fine tooth type external threads and interference fit shoulders are arranged at the two ends of the pipe body; has the advantages that: the invention improves the drilling depth, lightens the hook load, saves fuel, lightens the fatigue strength and improves the drilling speed; the stress corrosion fatigue resistance of the drill rod is improved by more than 10 times, the damage tolerance of the drill column is increased, and the service life of the drill column is prolonged; high mechanical strength, good flexibility, excellent corrosion resistance, low specific gravity and wide application range.

Description

A kind of steel joint titanium alloy pipe body thread connection type light drill pipe

technical field

The invention relates to the field of drill pipes, in particular to a threaded connection type light drill pipe of a steel joint titanium alloy pipe body.

Background technique

With the exploitation of oil and gas resources, the shallow oil and gas resources are decreasing day by day. We have to explore oil and gas resources in deeper strata, oceans and shale, and the working conditions are becoming more and more complex, and the requirements for drill pipes are higher, which need to be resistant to thermal cracking and shale. Hydrogen embrittlement, corrosion resistance, etc. Therefore, we urgently need a new material with lighter weight and higher strength-to-weight ratio to realize ultra-deep drilling and large horizontal displacement drilling that cannot be achieved by steel drill pipe.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a threaded connection type light drill pipe of steel joint titanium alloy pipe body in order to solve the deficiencies of the prior art.

The new technical scheme of the present invention is: a light-duty drill pipe of steel joint titanium alloy pipe body thread connection type, comprising a joint A, a joint B and a pipe body, both ends of the joint A are internal threads, and the joint A The internal thread of one end is the internal thread of a standard drilling tool, the internal thread of the other end of the joint A is a fine-toothed internal thread, the other end of the joint A is provided with a sealing shoulder A, and the end of the joint A is provided with a transition. Shoulder A, the tapered surface of the transition shoulder A is provided with an interference fitting shoulder A; one end of the joint B is an external thread, and the external thread is an external thread of a standard drilling tool, and the joint B is another One end is an internal thread, and the internal thread is a fine-toothed internal thread, the other end of the joint B is provided with a sealing shoulder B, and the end of the joint B is provided with a transition shoulder B, and the transition shoulder B The taper surface of B is provided with an interference fitting shoulder B; the end surfaces of the two ends of the pipe body are provided with sealing shoulder surfaces, and the sealing shoulder surfaces described at both ends are in phase with the sealing shoulder A and the sealing shoulder B. Matching; both ends of the pipe body are provided with fine-toothed external threads, and the fine-toothed external threads are matched with the fine-toothed internal threads of joint A and the fine-toothed internal threads of joint B; The end is provided with an interference fit shoulder, and the interference fit shoulder is an interference fit with the interference fit shoulder A of the joint A and the interference fit shoulder B of the joint B.

The joint A and the joint B are steel joints.

The pipe body is made of titanium alloy.

The included angle between the interference fitting shoulder A and the central axis of the joint A is 18°.

The fine-tooth external thread and the fine-tooth internal thread are flat trapezoids.

The taper of the fine-toothed external thread is 1:12-1:36.

The inner thread taper of the fine tooth type is 1:12-1:36.

The beneficial effects of the invention are as follows: the invention improves the drilling depth, reduces the hook load, saves fuel, reduces fatigue strength, and improves the drilling speed; the stress corrosion resistance fatigue strength of the drill pipe is increased by more than 10 times, and the damage tolerance and service life of the drill string are increased. ; High mechanical strength, good flexibility, excellent corrosion resistance, low specific gravity, and a wide range of applications.

Description of drawings

FIG. 1 is a schematic structural diagram of the present invention.

Figure 2 is a schematic structural diagram of a flat trapezoidal fine thread.

Among them: 1. Joint A; 2. Sealing shoulder surface; 3. Sealing shoulder A; 4. Interference fit shoulder; 5. Transition shoulder A; 6. Interference assembly shoulder A; 7. Pipe body; 8. Interference assembly shoulder B; 9. Transition shoulder B; 10. Sealing shoulder B; 11. Joint B.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings.

A steel joint titanium alloy pipe body threaded connection type light drill pipe, comprising a joint A1, a joint B11 and a pipe body 7, both ends of the joint A1 are internal threads, and the internal thread of one end of the joint A1 is a standard drill With internal thread, the internal thread of the other end of the joint A1 is a fine-tooth type internal thread, the other end of the joint A1 is provided with a sealing shoulder A3, the end of the joint A1 is provided with a transition shoulder A5, the The taper surface of the transition shoulder A5 is provided with an interference fitting shoulder A6; one end of the joint B11 is an external thread, and the external thread is an external thread of a standard drilling tool, and the other end of the joint B11 is an internal thread, and the internal thread is The thread is a fine tooth type internal thread, the other end of the joint B11 is provided with a sealing shoulder B10, the end of the joint B11 is provided with a transition shoulder B9, and the tapered surface of the transition shoulder B9 is provided with The interference assembly shoulder B8; the end faces of the two ends of the pipe body 7 are provided with a sealing shoulder surface 2, and the sealing shoulder surface 2 described at both ends is matched with the sealing shoulder A3 and the sealing shoulder B10; the said Both ends of the pipe body 7 are provided with fine-tooth external threads, and the fine-tooth external threads are matched with the fine-toothed internal threads of the joint A1 and the fine-toothed internal threads of the joint B11; the two ends of the pipe body 7 are provided with There is an interference fit shoulder 4, and the interference fit shoulder 4 is an interference fit with the interference fit shoulder A6 of the joint A1 and the interference fit shoulder B8 of the joint B11.

The joint A1 and the joint B11 are steel joints.

The pipe body 7 is made of titanium alloy.

The included angle between the interference fitting shoulder A6 and the central axis of the joint A1 is 18°.

The fine-tooth external thread and the fine-tooth internal thread are flat trapezoids.

The taper of the fine-toothed external thread is 1:12-1:36.

The inner thread taper of the fine tooth type is 1:12-1:36.

The joint A1 and the joint B11 and the pipe body 7 adopt a hot assembly process. During assembly, the joint is heated to a certain temperature to allow it to expand to a certain extent. After connecting with the pipe body 7, the joint cools and shrinks, so that the interference assembly of the joint A1 The shoulder A6 and the interference fitting shoulder B8 of the joint B11 form an interference fit with the interference fit shoulder 4 of the pipe body 7 respectively, which can effectively prevent the thread from shattering and play a sealing role.

A steel joint titanium alloy pipe body threaded connection type light drill pipe, the standard drill internal thread of the joint A1 and the standard drill external thread of the joint B11 are threadedly connected to form a drill pipe string; the drill pipe string is connected with other drill tools, From the bottom hole bit to the derrick drill pipe, the entire drill string is formed. The pipe body 7 accounts for more than 80% of the entire drill string length.

Claims (7)

1. The utility model provides a light-duty drilling rod of steel joint titanium alloy body threaded connection formula, includes joint A (1), joint B (11) and body (7), its characterized in that: the two ends of the joint A (1) are both provided with internal threads, the internal thread at one end of the joint A (1) is a standard drilling tool internal thread, the internal thread at the other end of the joint A (1) is a fine-tooth internal thread, a sealing shoulder A (3) is arranged in the other end of the joint A (1), a transition shoulder A (5) is arranged at the end part of the joint A (1), and an interference assembly shoulder A (6) is arranged at the conical surface of the transition shoulder A (5); one end of the joint B (11) is an external thread, the external thread is a standard drilling tool external thread, the other end of the joint B (11) is an internal thread, the internal thread is a fine-tooth internal thread, a sealing shoulder B (10) is arranged in the other end of the joint B (11), a transition shoulder B (9) is arranged at the end part of the joint B (11), and an interference assembly shoulder B (8) is arranged at the conical surface of the transition shoulder B (9); the end faces of the two ends of the pipe body (7) are provided with sealing shoulder surfaces (2), and the sealing shoulder surfaces (2) at the two ends are matched with the sealing shoulder A (3) and the sealing shoulder B (10); two ends of the pipe body (7) are provided with fine-tooth external threads which are matched with the fine-tooth internal threads of the joint A (1) and the joint B (11); the interference fit type pipe joint is characterized in that interference fit shoulders (4) are arranged at two ends of the pipe body (7), and the interference fit shoulders (4) are in interference fit with an interference fit shoulder A (6) of the joint A (1) and an interference fit shoulder B (8) of the joint B (11).

2. The steel joint titanium alloy pipe body threaded connection type light drill rod as claimed in claim 1, wherein: the joint A (1) and the joint B (11) are steel joints.

3. The steel joint titanium alloy pipe body threaded connection type light drill rod as claimed in claim 1, wherein: the pipe body (7) is made of titanium alloy.

4. The steel joint titanium alloy pipe body threaded connection type light drill rod as claimed in claim 1, wherein: the included angle between the interference assembly shoulder A (6) and the central axis of the joint A (1) is 18 degrees.

5. The steel joint titanium alloy pipe body threaded connection type light drill rod as claimed in claim 1, wherein: the fine thread type external thread and the fine thread type internal thread are flat trapezoids.

6. The steel joint titanium alloy pipe body threaded connection type light drill rod as claimed in claim 1 or 5, wherein: the taper of the fine-tooth external thread is 1: 12-1: 36.

7. the steel joint titanium alloy pipe body threaded connection type light drill rod as claimed in claim 1 or 5, wherein: the taper of the fine-tooth internal thread is 1: 12-1: 36.

Images