High-airtightness special buttress thread pipe joint

Abstract

The invention relates to a high-airtightness special buttress thread pipe joint, which comprises a coupling and a pipe body, wherein the middle part of the coupling is provided with an inner step cylindrical surface; the two ends of the coupling are provided with standard buttress inner threads; wedged inner threads are formed at the back ends of the buttress inner threads; the end part of the pipe body is provided with a standard buttress outer thread; a wedged outer thread is formed at the front end of the buttress outer thread; metal sealing structures are arranged between the two end faces of the inner step cylindrical surface and the end part of the pipe body respectively, and comprise an inner sealing structure arranged on the coupling, and an outer sealing structure arranged on the pipe body; the inner sealing structure comprises an inner conical surface and an inner shoulder angle projecting outwards; and the outer sealing structure comprises an outer conical surface and an outer shoulder angle depressing inwards. The wedged threads and a non-planar shoulder sealing structure are arranged on the end parts of the standard buttress threads, so that the connection strength, sealing performance, anti-bending capability, compression load resistance and anti-toque performance of the joint are improved.

Description

technical field [0001] The invention relates to an oil well pipe threaded joint used in the petroleum industry, in particular to a high-tight special partial trapezoidal threaded pipe joint. Background technique [0002] The oil and casing in the oil well pipe industry is mainly connected by threaded joints to form an oil and casing string with a length of several kilometers. Among them, the connection strength, sealing performance, bending resistance, torque resistance and tensile load of the threaded joints The quality of performance directly affects the connection quality of oil well pipes. Different geological structures require different types of threaded oil well pipes to meet the requirements of use. [0003] With the continuous development of oil field exploitation, the requirements for threaded joints of oil well pipes are becoming more and more stringent, especially the requirements for the main performance indicators of oil well pipes are getting higher and highe...

AI Technical Summary

Problems solved by technology

The existing API (American Petroleum Institute) partial trapezoidal thread joints have shortcomings such as weak torque resistance, low connection strength, poor sealing performance, and poor collapse resistance.

Oil well pipe processing enterprises in the world are constantly innovating on threaded joints, and different thread structure connection forms have appeared, but they still cannot meet the requirements of oil field production.

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