High-tightness buttress thread sleeve joint

Abstract

The invention relates to a high-tightness buttress thread sleeve joint, comprising a coupling and a sleeve body. An inner step cylinder is arranged at the middle part of the coupling; standard buttress internal threads are arranged at two ends of the coupling; wedge-shaped internal threads are arranged at the rear end of the buttress internal threads; standard buttress external threads are arranged at the end part of the sleeve body; wedge-shaped outer threads are arranged at the front end of the buttress external threads; metal sealing structures are respectively arranged between two end surfaces of the inner step cylinder and the end part of the sleeve body; each metal sealing structure comprises an inner sealing structure which is arranged on the coupling and an external sealing structure which is arranged on the sleeve body; the inner sealing structure comprises an inner circular conical surface and an inner shoulder chamfer which tilts outwards; the external sealing structure comprises an external circular conical surface and an external shoulder chamfer which tilts inwards. By adding the wedge-shaped threads and the shoulder sealing structures, the connection strength, the tightness performance, the bend resistance, the compressive load resistance and the torsion resistance of the joint are enhanced.

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 partial trapezoidal threaded casing connection 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 ...

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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