Defect detection equipment and method for boiler water-cooled wall tubes based on low-frequency electromagnetic technology

Abstract

The invention discloses equipment and a method for detecting defects of a boiler water cooling wall tube on the basis of a low-frequency electromagnetic technique. The equipment comprises a power supply module, a processor, a touch screen, an excitor, a scanning probe, a signal preprocessing circuit and a power supply module, wherein the signal preprocessing circuit is used for preprocessing a signal received by the scanning probe; the power supply module is used for supplying power; the output end of the processor is connected with the input end of the scanning probe through the excitor; the output end of the scanning probe is connected with the input end of the signal preprocessing circuit; the processor is connected with the signal preprocessing circuit and the touch screen. By adopting the equipment and the method, detection on internal defects of the boiler water cooling wall tube can be rapidly and accurately completed, and the equipment and the method are applicable to sealed tubes.

Description

technical field [0001] The invention belongs to the technical field of low-frequency electromagnetic nondestructive testing, and relates to a defect detection device and method for boiler water-cooled wall tubes based on low-frequency electromagnetic technology. Background technique [0002] The water wall of power plant boilers is an important equipment for boiler operation. The water wall tubes have been in service for a long time under harsh working conditions such as high temperature and high pressure corrosive media, and are prone to failure caused by corrosion under scale on the inner wall. For the non-destructive testing of in-service water wall tubes, conventional methods such as ultrasonic, infiltration, magnetic particle, and eddy current are usually used. Ultrasonic is a contact measurement method that requires a couplant. It has low measurement accuracy and low detection efficiency for volume-type defects such as corrosion pits. Penetration and magnetic particle...

AI Technical Summary

Problems solved by technology

Ultrasonic is a contact measurement method that requires a couplant. It has low measurement accuracy and low detection efficiency for volumetric defects such as corrosion pits.

Penetration and magnetic particle methods have high sensitivity, but they are only suitable for detecting surface and near-surface cracks, and cannot detect inner wall defects

Eddy current testing requires the probe to pass through the inside of the pipe, which is not suitable for closed pipes

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