Patent ID: 7204147

Claim:
An ultrasonic inspection method to evaluate a welding condition in a weld zone of a flange and a web of an actual piece to be measured, said method comprising: preparing test pieces, including a basic test piece, such that each of said test pieces has a slit with substantially a same shape as a slit in the weld zone of the actual piece to be measured, and such that the slit of each of said test pieces has a different height; transmitting ultrasonic pulses with a probe to said slit and measuring echoes with said probe while positioning the probe at a plurality of measuring positions of each of said test pieces; determining a measuring position where an echo height extracted from a measured echo of the basic test piece is clearly distinguishable from echo heights extracted from measured echoes of other test pieces at the measuring position; providing master data based on the echo heights extracted from the measured echoes of each of said test pieces at said determined measuring position; locating said probe at said determined measuring position on said flange or said web of said actual piece to be measured; transmitting ultrasonic pulses with said probe to said slit in said weld zone of said actual piece to be measured and measuring echoes with said probe at a plurality of positions on said flange or said web; comparing said measured echoes returned from said weld zone with said master data; determining a welding condition at said weld zone based on said comparison.