Pipeline nondestructive testing device based on electric field fingerprint method

Abstract

The invention discloses a pipeline nondestructive testing device based on an electric field fingerprint method, belonging to the field of pipeline nondestructive testing technical equipment. The device comprises a to-be-tested pipeline (2) and a voltage acquisition area (3) formed in the to-be-tested pipeline (2), wherein multiple capture electrodes are arranged in the voltage acquisition area (3) in the same distance; current input units are arranged on two sides of the voltage acquisition area (3); and the pipeline nondestructive testing device is characterized in that the capture electrodes are fixed on the surface of the to-be-tested pipeline (2) in a non-welding form by virtue of multiple groups of capture electrode fixing sleeves (4) in the voltage acquisition area (3). According to the device, the capture electrodes are fixed on the surface of the to-be-tested pipeline in the non-welding form by virtue of the multiple groups of capture electrode fixing sleeves, accurate detection of the electric field fingerprint method is realized, and nondestructive testing of the to-be-tested pipeline is really realized.

Description

technical field [0001] The invention discloses a pipeline nondestructive testing device based on an electric field fingerprint method, which belongs to the field of pipeline nondestructive testing technical equipment. Background technique [0002] At present, the resistance probe method and polarization probe method are widely used to monitor the corrosion of pipelines online, but these methods can only detect indirect uniform corrosion, and have damage to the pipe wall. It can't do anything about the extremely harmful localized corrosion. Using the electric field fingerprint method to detect pipeline corrosion has the advantages of direct measurement, high accuracy and reliability, strong adaptability, and no damage to the pipeline wall. [0003] The basic principle of the electric field fingerprint method is: weld the capture electrode on the corrosion-prone part of the pipeline to be tested. After the welding is completed, apply a large current signal to the capture elec...

AI Technical Summary

Problems solved by technology

[0005] 1. Welding has high requirements for welding equipment. According to different pipeline materials and electrode materials, welding equipment requirements are different, welding process parameters are different, and it is difficult to explore one by one; for indoor construction, some pipelines are located in narrow locations, and welding operations are difficult. Even welding is impossible, which greatly limits the application range of the technology; correspondingly, for field construction, it is inconvenient to set up the power supply, and the welding equipment is heavy and cannot be flexibly constructed, which also greatly limits the popularization and use of this technology

These defects have increased the installation cost of the device while bringing a lot of trouble to the on-site construction

[0006] 2. The welding connection method is used to weld the capture electrode and the pipeline to be tested. Although the degree is relatively small, it is a kind of damage to the pipeline to be tested. It is more harmful to thin-walled pipelines and violates the principle of non-destructive testing to a certain extent. in principle

[0007] 3. The technical application direction of the electric field fingerprint method is mainly for the detection of petrochemical and other pipelines. One of the advantages of this technology is that the device does not need to stop production, but welding is easy to generate open flames, which is not suitable for operation in high-risk environments

[0008] 4. Using the welding method cannot guarantee that each welded joint is exactly the same, and the resulting welding contact resistance will be different, and the small resistance difference will obviously affect the collection of micro-voltage signals, which limits the high-precision detection of voltage signals

[0009] 5. The firmness of the welding joint between the capture electrode and the structure to be tested needs to be tested, and at the same time, stress concentration is easily formed at the welding joint, which affects the safety of high-pressure pipelines; at the same time, the welding joint is relatively easy to corrode, and the anti-corrosion requirements are relatively high

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