Patent ID: 9594001
Date: 2017-03-14
CPC Classifications: G01M,G01N

Claim:
1. An ultrasonic testing device that immerses a differential casing to which a ring gear is welded into liquid, and detects a weld defect in a welded part of the differential casing based on an ultrasonic wave, the ultrasonic testing device comprising: a liquid tank that stores the liquid into which the differential casing is to be immersed; a workpiece holder that holds the differential casing and immerses the differential casing into the liquid in the liquid tank; an ultrasonic probe that conducts an ultrasonic testing of the welded part of the differential casing by irradiating the ultrasonic wave to the welded part and receiving a reflected wave; an image processing module that generates an ultrasonic image based on the reflected wave received by the ultrasonic probe; and a replacer that replaces gas inside an air gap formed at a weld toe of the welded part with test liquid, wherein the replacer replaces the gas inside the air gap by the test liquid before the ultrasonic probe irradiates the ultrasonic wave, and replaces the gas inside the air gap with the test liquid with the help of negative pressure generated when vacuuming the air gap.