A Circumferential Electromagnetic Field Pipeline Inner Wall Crack Detection System and Quantitative Evaluation Method

Abstract

The invention discloses a pipeline inner wall crack detection system and evaluation method based on a circumferential electromagnetic field, including a bench, a pipeline, a probe, a fixture, a piston rod, a hydraulic cylinder, a computer, a PLC, a driver, a motor, an oil pump, a safety valve, a regulator Speed ​​valve, signal generator, power amplifier and acquisition card, the piston rod is installed in the center of the piston coaxial with the inner hole of the hydraulic cylinder, the probe is installed at the end of the piston rod by the central hole, and the probe is coaxially placed in the pipeline Internally, the computer is respectively connected with the PLC, the acquisition card and the signal generator, the driver is connected with the oil pump through the motor, the signal generator is connected with the excitation coil in the probe through the power amplifier, and the flexible circuit board in the probe is The amplifier is connected with the acquisition card. The beneficial effects of the invention are: the quantitative and location evaluation of the axial and circumferential cracks on the inner wall of the pipeline can be realized by means of the annular electric field and the alternating magnetic field, and all the cracks on the inner wall of the pipeline can be comprehensively quantified and evaluated at one time.

Description

technical field [0001] The invention relates to a crack quantitative detection system, in particular to a pipeline inner wall crack detection system and evaluation method based on a circumferential electromagnetic field. Background technique [0002] Stress corrosion cracks in the inner wall of pipelines are an important factor causing pipeline leakage. It is of great significance to carry out the design of quantitative detection system for cracks on the inner wall of pipelines to evaluate the size of cracks in time and effectively prevent pipeline rupture. In general, stress corrosion cracking on the inner wall of the pipeline is in the axial direction, and circumferential cracking is prone to occur at the position of the circular weld. Traditional magnetic flux leakage technology is difficult to detect axial cracks; eddy current testing technology has poor quantitative accuracy, and it is difficult to effectively evaluate the size of cracks; ultrasonic testing technology ...

AI Technical Summary

Problems solved by technology

Traditional magnetic flux leakage technology is difficult to detect axial cracks; eddy current testing technology has poor quantitative accuracy, and it is difficult to effectively evaluate the size of cracks; ultrasonic testing technology is poor in detecting shallow cracks on the inner wall of the pipeline; the internal penetration ACFM probe can provide 360° on the inner wall of the pipeline. The current field can detect axial cracks, but it does not provide a quantitative method for cracks on the inner wall of the pipeline, and the detection effect on circumferential cracks is poor.

Images