CN205243440U - Special screw thread coupling of detaining of industrial tub of 3 -12 " of oil and natural gas - Google Patents

Abstract

The utility model relates to a 3-1/2" special thread coupling for oil and gas industry pipes, which includes a pipe body, an internal thread and a middle wall ring. The main body of the coupling is a cylindrical pipe body. Both ends of the axial direction are coaxially made with 3-1/2" internal threads, and the middle section of the pipe body is made with a middle wall ring that is flush with the inner diameter of the pipe body, and at the root position where the middle wall ring is connected to the inner wall of the pipe A middle wall slope inclined to the middle is made, and a transition slope is made between the internal thread and the middle wall ring, so that an annular cone angle inclined to the middle is formed at the root of the middle wall ring, and there is a gap between the ring cone angle and the internal thread Smooth midwall ring. The utility model adopts high-precision coupling connection, and the joint strength is high; the trapezoidal thread is adopted, the strength of the thread buckle type is high, and the sealing performance of the bimetallic interference fit is good, and the thread surface is treated with sandblasting and phosphating, and the thread is resistant to corrosion. Good adhesive performance, easy to install and maintain.

Description

A kind of 3-1/2" special buckle thread coupling for oil and gas industry pipe

technical field

The utility model belongs to oil pipe connectors, in particular to a 3-1/2" special buckle thread coupling for oil and gas industry pipes.

Background technique

With the change of the oil field production environment, various complex well conditions such as deep wells and high-pressure oil and gas wells put forward better requirements for the connection strength and sealing performance of the tubing. At present, the oil pipes commonly used at home and abroad are generally produced using the "API" technical standard, but in actual production, the actual production process requires more and more complicated oil pipe structures, and different diameters need to be installed at different operating positions. Therefore, it is necessary to connect different types of oil pipes. Sometimes multiple adapters are needed to meet the requirements of the connection process and the production process. The existing BC buckle type of API5CT5B standard has been difficult to meet the thread strength and sealing performance. Process requirements, accuracy is difficult to guarantee.

Utility model content

The purpose of the utility model is to overcome the deficiencies of the prior art, and provide a 3-1/2" special buckle thread coupling for oil and gas industry pipes with simple structure, high precision, high connection strength, safety and reliability.

The utility model solves its technical problem and realizes by taking the following technical solutions:

A 3-1/2" special threaded coupling for oil and gas industry pipes, including a pipe body, an internal thread and a middle wall ring. The main body of the coupling is a cylindrical pipe body. 3-1/2"internal threads are coaxially made inside the ends, and a middle wall ring flush with the inner diameter of the pipe is made in the middle section of the pipe body. A middle wall slope inclined to the middle is made, and a transition slope is made between the internal thread and the middle wall ring, so that an annular cone angle inclined to the middle is formed at the root of the middle wall ring, and there is a gap between the ring cone angle and the internal thread Smooth midwall ring.

Moreover, conical chamfers are formed at both ends of the pipe body.

Moreover, the internal thread adopts 25.4mm trapezoidal thread with 8 teeth or 6 teeth.

Advantage and positive effect of the present utility model are:

1. The utility model adopts a high-precision coupling to connect, and the joint strength is high; it adopts a trapezoidal thread, and the thread buckle type has high strength, and the sealing performance of the bimetallic interference fit is good.

2. The thread surface of the utility model adopts sandblasting and phosphating treatment, the thread has good anti-sticking performance, and is convenient for installation and maintenance.

3. The API5CT steel grade range of this utility model is suitable for special environmental requirements such as deep wells and high-pressure oil and gas wells. It has high connection strength and strong sealing performance, and can be used for special stressed pipes such as high corrosion resistance and anti-destruction.

Description of drawings

Fig. 1 is the structural front view of the present utility model;

Fig. 2 is a partially enlarged view of part A in Fig. 1 .

detailed description

The utility model will be further described in detail below in conjunction with the accompanying drawings and through specific embodiments. The following embodiments are only descriptive, not restrictive, and cannot limit the protection scope of the utility model.

A 3-1/2" special threaded coupling for oil and gas industry pipes, including a pipe body 1, an internal thread 2 and a middle wall ring 3, the main body of the coupling is a cylindrical pipe body 1, and the Both ends of the axial direction are coaxial with 3-1/2" internal thread 2, the internal thread adopts 25.4mm trapezoidal thread with 8 teeth or 6 teeth, and the thread buckle has high strength; the thread surface is treated with sandblasting or phosphating For rough surfaces, avoid thread sticking.

The middle part of the pipe body is formed with a middle wall ring 3 which is flush with the inner diameter of the pipe, and the middle wall ring 3 ensures that the inner diameter of the joint part is the same as that of the pipeline to ensure smooth flow of the pipeline and a stable flow rate.

Conical chamfers 4 are formed on both ends of the pipe body, which is convenient for connecting the pipe head into the coupling during installation.

The innovation point of the present utility model is:

In order to enhance the tightness of the connection, an inwardly inclined annular cone angle is made at the connection position between the internal thread and the middle wall ring. The cross-sectional shape of the annular cone angle is shown in Figure 2, at the root position where the middle wall ring is connected to the inner wall of the pipe A middle wall slope 7 inclined toward the middle is formed, and a transition slope 6 is formed between the internal thread and the middle wall ring, so that an annular cone angle inclined toward the middle is formed at the root of the middle wall ring, so that the connecting end and the pipe The inner wall forms a metal interference fit to effectively ensure the tightness of the connection.

The included angle between the middle wall slope and the transition slope is made into a circular arc angle to improve the connection strength and service life of the root.

There is a smooth middle wall ring 5 between the annular cone angle and the internal thread, which reduces damping and facilitates assembly.

The accompanying drawings of this embodiment are based on JGST special buckle 3-1/2" threaded coupling as an example, where JG means Seiko, S means air seal, T means tubing, and 3-1/2" belongs to the thread parameters of API5B standard . The thread parameters described in this embodiment implement the API5B standard to maintain the versatility and interchangeability of products.

Although the embodiments and drawings of the utility model are disclosed for the purpose of illustration, those skilled in the art can understand that various replacements, changes and modifications can be made without departing from the spirit and scope of the utility model and the appended claims. It is possible, therefore, the scope of the present invention is not limited to the contents disclosed in the embodiments and drawings.

Claims (3)

1. A 3-1/2 "special thread coupling for oil and gas industry pipes, including a pipe body, internal threads and a middle wall ring, the main body of the coupling is a cylindrical pipe body, and the shaft of the pipe body 3-1/2"internal threads are coaxially formed inside both ends, and a middle wall ring flush with the inner diameter of the pipe is formed in the middle section of the pipe body. It is characterized in that: the middle wall ring is connected with the inner wall of the pipe The root position is made with a middle wall slope inclined to the middle, and a transition slope is made between the internal thread and the middle wall ring, so that an annular cone angle inclined to the middle is formed at the root of the middle wall ring, and the gap between the ring cone angle and the internal thread A smooth midwall ring remains. 2. The 3-1/2" special threaded coupling for oil and gas industry pipes according to claim 1, characterized in that: both ends of the pipe body are provided with conical chamfers. 3. The 3-1/2" special thread coupling for oil and gas industry pipes according to claim 1, characterized in that: the internal thread adopts 25.4mm trapezoidal thread with 8 threads or 6 threads.