Testing device and testing method for magnetic flux leakage of petroleum gas storage well casing

Abstract

The invention relates to a testing device and a testing method for magnetic flux leakage of a petroleum gas storage well casing. The testing device comprises a ground PC machine, a centering device and an underground instrument, wherein the ground PC machine is connected with the underground instrument through a cable; the underground instrument is connected with the centering device; the centering device and the underground instrument move up and down in the casing through the self weight of the underground instrument and the pull force of the cable; a signal acquisition unit of the underground instrument comprises a transverse magnetizer, a transverse detection unit, a wall thickness detection unit, a longitudinal magnetizer and a longitudinal detection unit, which are connected in sequence; the transverse detection unit comprises at least one transverse probe; the wall thickness detection unit comprises a 4*4 Hall element; the longitudinal detection unit comprises a plurality of longitudinal probes which are uniformly distributed on the circumference; each longitudinal probe comprises a longitudinal magnet and a plurality of groups of coils wound on the longitudinal magnet. According to the testing device and the testing method, provided by the invention, the problem that influences, caused by an underground environment, on a gas storage well casing damage detection method is solved; inner and outer damage conditions of the casing can be detected simultaneously by utilizing a magnetic flux leakage flaw detection technology and the detection is not influenced by an underground fluid environment.

Description

technical field [0001] Gas storage well wellbore wall thickness and corrosion detection system and method are non-destructive testing equipment specially designed for various types of gas storage wells used in gas filling stations, peak shaving stations and other related facilities to measure wall thickness and corrosion degree to evaluate their safety status and technical means. Background technique [0002] Natural gas is a clean and environmentally friendly high-quality energy source, which contains almost no sulfur, dust and other harmful substances. When burned, it produces less carbon dioxide than other fossil fuels, resulting in a lower greenhouse effect, which can fundamentally improve the quality of the environment. As natural gas is more and more popular due to its environmental protection and economic benefits, and the utilization rate of natural gas is increasing, so in recent years, many natural gas filling stations and natural gas pipeline networks have appeare...

AI Technical Summary

Problems solved by technology

[0008] In order to solve the technical problem that the existing gas storage well casing damage detection method is greatly affected by the downhole environment and the detection is not comprehensive, the present invention provides a casing magnetic flux leakage testing device and testing method for petroleum gas storage wells. The magnetic flux leakage flaw detection technology can be used to Simultaneously detect the internal and external damage of the casing, and is not affected by the downhole fluid environment. The invention belongs to non-contact measurement and is suitable for casing damage diagnosis and general inspection during workover operations

Images