Metal-to-metal sealing structure of premium thread of oil well pipe for high-performance screwed joint

Abstract

The invention is used for a metal-to-metal sealing structure of a premium thread of an oil well pipe for a high-performance screwed joint. According to the wall thickness change of a front end wall of a male end of a pipe body, a single-segment sealing contact part of the structure can obtain a single-segment sealing structure and a multiple-segment sealing structure and a single-segment sealing contact part and a female nut of a pipe body are sealed so that control structures of opening and non-opening are adopted to the top platform shoulder and a tip corner such that a coupling female end sealing part and a sealing part of a male end of the pipe body are closely attached. The male end of the pipe body is sealed with the pipe body of the coupling female end in a threaded mode to press against the top platform shoulder and the female threaded sealing of the pipe body is used for pressing against the top platform shoulder. The metal-to-metal sealing structure of the premium thread of the oil well pipe for the high-performance screwed joint has following beneficial effects: sealing protection is formed by a multiple-stage sealing structure such that corrosive mediums do not seep into nuts and are prevented against damage by corrosive mediums; service lifetime of the oil well pipe is prolonged; the maximum value of sealing contract stress for interference of four sections of male and female sealing surfaces ranges from 1200 to 1400 MPa; the contact length with stress value points is longer than 12mm; and the contact area is large and stress is more uniform and reasonable.

Description

technical field [0001] The invention relates to a metal-to-metal sealing structure of a special buckle oil well pipe with a high-performance threaded joint, which is suitable for use by oil field users under the well conditions of high downhole gas pressure and strict requirements on sealing performance during oil and gas field exploitation. Background technique [0002] In the process of adopting threaded special buckle oil well pipes in use, because the oil and gas reserve resources are getting less and less, the mining site conditions are getting worse and worse. In addition, there are various corrosive media such as H2S and CO2 gas, Cl ions in the downhole. These corrosive media As time goes by, if the single-stage seal fails, the corrosive medium will gradually invade into the thread along the leakage channel, and continuously corrode the pipe body and coupling thread, which will reduce the sealing ability of the oil well pipe and shorten the service life of the oil well...

AI Technical Summary

Problems solved by technology

[0002] In the process of adopting threaded special buckle oil well pipes in use, because the oil and gas reserve resources are getting less and less, the mining site conditions are getting worse and worse. In addition, there are various corrosive media such as H2S and CO2 gas, Cl ions in the downhole. These corrosive media As time goes by, if the single-stage seal fails, the corrosive medium will gradually invade into the thread along the leakage channel, and continuously corrode the pipe body and coupling thread, which will reduce the sealing ability of the oil well pipe and shorten the service life of the oil well pipe. decline

After the seal of the oil well pipe fails, the natural gas and oil inside the oil well will leak. If the natural gas leaks, it will cause serious personal casualties. If the oil leaks, it will cause major marine environmental pollution.

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