The main reason for demagnetization of spiral welded pipes - ensuring detection accuracy

Residual magnetism also affects the inspection of spiral welded steel pipes. For instance, in X-ray industrial television imaging systems, residual magnetism can deflect the direction of the electron beam in the image intensifier, leading to an "S"-shaped distortion in the image. This distortion can impact the detection effectiveness of natural defects such as pores and slag inclusions, particularly reducing the detection rate of linear natural defects such as incomplete penetration and cracks. Therefore, to ensure the accuracy of inspection results, demagnetization treatment is required for spiral welded steel pipes.