Patent ID: 8820163

Claim:
A nondestructive inspection apparatus comprising: a pair of guided wave sensors which are disposed on an outer surface of piping; a guided wave inspection device which is connected to said pair of guided wave sensors, outputs a transmitting signal for propagating a guided wave to said guided wave sensors, and obtains a receiving signal by receiving a propagated signal by said guided wave sensors; an inspection-result storage device for storing the guided wave received by said guided wave inspection device as a digitized signal of the received wave; and an inspection-result diagnostic device for, by taking the added value or differential value of back-and-forth propagation time of receive wave which exceeds a predetermined threshold value in a signal of each received wave acquired by transmitting a guided wave by use of said guided wave inspection device into the piping by use of said guided wave inspection device, performing arithmetic processing of judging whether or not a signal associated with a defect exists.