Patent ID: 8627722

Claim:
A welding inspection method, comprising: launching an ultrasonic wave from a probe to a welded part where a welding has been carried out for a plurality of stacked metal plates; receiving a reflected wave of the ultrasonic wave reflected inside the stacked metal plates and at the welded part, by means of the probe at the same location as the ultrasonic wave being launched, to check quality of the welding; wherein the ultrasonic wave is launched to a boundary plane of the stacked metal plates by the probe being temporarily placed in the proximity of the welded part on a surface of the stacked metal plates, such that a propagation direction of the ultrasonic wave is oblique to a surface of the stacked metal plates when the ultrasonic wave enters the metal plates; and analyzing how the ultrasonic wave passing through the stacked metal plates, reflected at an end of the stacked metal plates and returned to the probe is affected by the welded part.