Probe Configurations
Regardless of whether pitch-cath ultrasonic testing is done with direct beams or reflected beams, flaws are detected by comparing the intensity of ultrasound transmitted through the testpiece with the intensity transmitted through a reference standard made of the same material. One exception to this is the side-by-side dual element probe commonly known as T/R probes or dual probes where the same flaw detection conditions of Pulse-echo are kept. Pitch catch testing requires two search units-one to transmit the ultrasonic waves and one to receive them.
Possible configurations of Pitch-catch ultrasonic are the overmentioned (a)dual probe /side by side arrangement, (b) reflection and (c)transmission.