Patent ID: 6920791

Claim:
A method for the ultrasonic inspection of lap welds between a first metal sheet and a second metal sheet, said method comprising the steps of: applying a first wheel probe to a surface of the first metal sheet, emitting ultrasonic pulses at an angle ranging between 15 degrees and 80 degrees relative to the surface of the first metal sheet and generating a transverse wave in the first metal sheet; allowing the ultrasonic pulses to pass through the lap weld; applying a second wheel probe to a surface of the second metal sheet and receiving the ultrasonic pulses that have propagated through the lap weld into the second metal sheet; providing a frame for carrying the first wheel probe and the second wheel probe; wherein the first wheel probe comprises in combination a first axle body that is non-rotatable relative to said frame, said first axle body defining a first axial line which is oriented substantially parallel to the surface of the first metal sheet, a first ultrasonic transducer fastened to the first axle body, and a first tire that is rotatable about the first axle body, wherein said first tire is coupled to the first ultrasonic transducer, is dry-coupled to the first metal sheet and rolls over the first metal sheet parallel to the lap weld; wherein said second wheel probe comprises in combination a second axle body that is non-rotatable relative to said frame, said second axle body defining a second axial line which is oriented substantially parallel to the surface of the second metal sheet, a second ultrasonic transducer fastened to the second axle body and a second tire that is rotatable about the second axle body, wherein said second tire is elastically mounted to the frame, is coupled to the second ultrasonic transducer, is dry-coupled to the second metal sheet and rolls over the second metal sheet parallel to the lap; weld; and evaluating the pulses received.