At present, there are four main types of oil casing special buckles designed and developed by countries around the world, namely: VM series, Hydrir series, Hunting series, Tenaris series.

Features of special buckle

Although the design of special fasteners for petroleum casing varies from country to country, the basic form is basically the same, mainly to improve the connection strength and sealing performance of the pipe string.

On the other hand, most special buckles for oil bushings are divided into three parts: the connecting thread part, the torque-resistant workbench shoulder and the sealing surface part.

Most adopt API trapezoidal threads to improve the interchangeability of threaded parts.

The advantages of special buckle:

In the initial stage of the use of oil well pipes, special buckles are designed for different oil fields, different blocks and different well conditions, with strong personalized colors. However, with the increasing complexity of well conditions, the use conditions of pipelines have become more stringent. After comparison, screening and actual tests of various special buckles abroad, more than 10 typical products have been gradually formed, which can basically meet the special needs of the current oil field. Although various special deduction products can meet the needs of drilling and production under different simultaneous conditions, they all have the following common advantages:

1. The connection strength of the joint can match the strength of the pipe body, and even some joint strengths higher than the pipe body are suitable for deep wells and ultra-deep wells;

2. Has good sealing performance, suitable for high-pressure gas wells, oil wells and thermal recovery wells

3. Strong bending resistance, suitable for supporting wells, large displacement wells and horizontal wells;

4. It is easy to fix, fasten fast, and it is not easy to drill in harsh environments such as deserts and oceans;

5. Good anti-stick performance, can be removed repeatedly without damaging the thread;

6. Strong torque resistance;

7. Good corrosion resistance.