DEVICE AND METHOD FOR ULTRASONIC FLAW DETECTION OF BLADE GROOVE PART OF TURBINE ROTOR DISK

摘要

PROBLEM TO BE SOLVED: To highly accurately detect a defect such as a crack without requiring troublesome appurtenant work in a curved side-entry type blade groove part.SOLUTION: A method for ultrasonic flaw detection of a blade groove part of a turbine rotor disk comprises: an arrangement process of arranging a phased-array probe including a plurality of vibrators capable of transmitting ultrasonic waves respectively on an end surface of a rotor disk in the parallel state where the plurality of vibrators are arranged in parallel along the circumferential direction of the rotor disk; a first transmission and reception process of transmitting the ultrasonic waves from the plurality of vibrators in the parallel state with the ultrasonic transmission timing of each of the plurality of vibratos being controlled in the first transmission pattern and receiving the reflection waves of the ultrasonic waves; and a second transmission and reception process of transmitting the ultrasonic waves from the plurality of vibratos in the parallel state with the ultrasonic transmission timing of each of the plurality of vibratos being controlled in the second transmission pattern different from the first transmission pattern and receiving the reflection waves of the ultrasonic waves.SELECTED DRAWING: Figure 1