Special type oil well pipe with changed materials and structural layers at two ends and manufacturing method thereof

Abstract

The invention discloses a special type oil well pipe with changed materials and structural layers at two ends and manufacturing method thereof, and aims to solve the problems that the oil well pipe leaks and is broken in a well and the service life of the oil well pipe is reduced because the end part of the conventional oil well pipe is easy to abrade eccentrically. In the special type oil well pipe, end pipe bodies are welded at the two ends of an oil well pipe parent body; the inner diameter of each end pipe body is the same as that of the oil well pipe parent body; the wall of the each endpipe body is thicker than the wall of the oil well pipe parent body; and threads are formed on the outer surfaces of the end pipe bodies. The manufacturing method comprises the following steps of: (1) processing a threaded structure; (2) hardening and tempering; (3) performing nitriding treatment; (4) performing oxidation treatment; (5) welding the space between the oil pipe parent body and the end pipe bodies; (6) performing a hydrostatic test; and (7) performing flaw detection. The invention has the advantages that: cost is reduced; the oil well pipe cannot leak and cannot be broken in the well; and the service life of the oil well pipe is prolonged by more than 10 times.

Description

technical field [0001] The invention relates to a special oil well pipe and its manufacturing method, in particular to a special oil well pipe with changed materials and structural layers at both ends and its manufacturing method. Background technique [0002] At present, the corrosion, eccentric wear, and sticking of downhole oil well pipes in oil and gas fields are particularly serious, which are the three major problems that plague the service life of oil well pipes. High concentration, high content of sulfate-reducing bacteria (SRB), CO 2 In this corrosive environment, the downhole oil well pipe is easy to corrode, especially when working, the unique appearance of the sucker rod in the oil well pipe and the complex well conditions cause the two ends of the oil well pipe to appear Severe partial wear often presents the following problems: [0003] 1. The thread at the end of the oil well pipe is lost due to eccentric wear, which leads to a sharp drop in production and a...

AI Technical Summary

Problems solved by technology

[0006] The purpose of the present invention is to provide a special oil well pipe with changed materials and structural layers at both ends and its manufacture in order to solve the problems that the end of the existing oil well pipe is prone to eccentric wear, which leads to leakage, well breakage and reduced service life of the oil well pipe. method

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