Sealed threaded connection assembling method for combination of oil pipe and casing pipe

Abstract

The invention provides a sealing threaded connection assembly method for an oil pipe and casing pipe combination, which comprises the following steps: S1, arranging external threads, axial shoulders and sealing shoulders at the end parts of two sections of bimetal composite pipe bodies, arranging external threads and positioning shoulders at the end part of an assembly short section, machining internal threads on the inner walls of two ends of a coupling, machining a sealing groove in the middle, and sealing the two sections of bimetal composite pipe bodies; s2, the first end of the coupling is in threaded connection with the assembling short section, and the threads are screwed into a positioning shoulder of the assembling short section to make contact with the coupling face; s3, anti-loosening oil fixing casing pipe thread compound and anti-thread-gluing oil casing pipe thread compound are smeared on external threads of the first section of bimetal composite pipe body in a segmented mode, and the first section of bimetal composite pipe body is in threaded connection with the second end of the coupling and screwed into the end face of the pipe body to make contact with the end face of the assembling short section; s4, disassembling the assembly short section; and S5, external threads of the second-section bimetal composite pipe body are coated with anti-thread-gluing oil casing thread grease, and the second-section bimetal composite pipe body is in threaded connection with the first end of the coupling and screwed into the end face of the first-section bimetal composite pipe body to make contact with the end face of the first-section bimetal composite pipe body.

Description

technical field [0001] The invention relates to the technical field of oil and casing pipes used in the exploration and development of energy sources such as oil, natural gas, and coalbed methane, and in particular relates to an assembly method for sealing and threaded connection of oil pipes and casings. Background technique [0002] During the exploration and development of energy such as oil, natural gas, and coalbed methane, it is necessary to use oil and casing strings to stabilize the well wall and form oil and gas passages. At present, the oil and casing strings are often threaded to form a single oil and casing string, so the threaded connection has the functions of connection and sealing. Conventional special threads with excellent sealing performance require high machining accuracy and high contact pressure on the sealing surface, especially when the oil casing is in a stretched state, the contact pressure of the sealing surface will decrease under the action of te...

AI Technical Summary

Problems solved by technology

[0004] In view of this, the present invention provides an assembly method for a sealed threaded connection of a combination of oil pipe and casing, which uses common / standard API oil and casing threads, and overcomes the problems that may occur when the top thread is connected and assembled in the prior art. Reverse torque loosening at the factory end, incomplete topping of the shoulder face, and sealing problems under tensile load

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