Study on Abnormality Electromagnetic Testing abnormal of Thin-walled Gr.2 Titanium Tubes

Ultrasonic testing, penetration testing and metallographic testing were used to analyze the abnormality during electromagnetic testing of thin-walled gr.2 titanium tubes. The characteristics of ET alarm appeared continuously and were found in misalignment with phase angle of standard pipe alarm signal. The possible causes of alarm were analyzed and the cause of ET alarm procedures was found between different processes. Alarm signal of the pipes was eliminated by slipped rolling method and it was confirmed that straightening was the main reason of ET abnormality. By using the method of straightening with liner tube, the problems of ET alarm were solved.