Pipe weld flaw detection apparatus and method

摘要

PROBLEM TO BE SOLVED: To provide a device and method for flaw detection in welded parts of pipes by which the position of any flaw existing near welded parts all around a hollow pipe can be accurately located by precisely checking welded parts existing near the surface of the hollow pipe from inside and making the flaw visible.SOLUTION: A flaw detecting device is equipped with a hollow cylindrical guide rail 12 that is coaxial with and can be detachably fixed to the outer circumference surface 1a of a hollow pipe 1, a phased array probe 14 that performs transmission and reception by radially varying the direction of an ultrasonic beam S in the axial direction of the hollow pipe 1 by sector scanning, and a probe guide 16. The probe guide 16 is so configured as to hold the phased array probe 14 in such a manner as to cause the ultrasonic beam S to come incident inclined in the axial direction from the outer circumference surface 1a and to shift the phased array probe 14 in the circumferential direction along the outer circumference surface 1a following the guide rail 12.SELECTED DRAWING: Figure 6