GB/T 5777-2008

This standard specifies the principles of ultrasonic flaw detection for seamless steel pipes, detection methods, comparison samples, detection equipment, detection conditions, detection steps, result evaluation, and detection reports. This standard applies to ultrasonic inspections of longitudinal and transverse defects in seamless steel pipes for various purposes. The detection method described in this standard is mainly used to inspect defects that have destroyed the continuity of the steel pipe metal, but it cannot effectively inspect layered defects. This standard applies to steel pipes with an outer diameter of not less than 6mm and a wall thickness-to-outer diameter ratio of not more than 0.2. For steel pipes with a wall thickness-to-outer diameter ratio greater than 0.2, the inspection can be carried out in accordance with Appendix C of this standard after consultation between the supplier and the buyer.