ULTRASONIC FLAW DETECTION METHOD AND METHOD OF PRODUCING SEAMLESS TUBE

摘要

A circumferential angle of incidence ±i of an ultrasonic wave transmitted from an ultrasonic probe 1 upon a tubular test object P and an axial angle of incidence ²i of the ultrasonic wave transmitted from the ultrasonic probe 1 upon the tubular test object P are set based on a ratio of thickness to outer diameter t/D of the tubular test object P so that an internal refraction angle ¸k calculated from the circumferential angle of incidence ±i, the axial angle of incidence ²i, and the ratio of thickness to outer diameter t/D of the tubular test object may be not less than 35° and not more than 60°.