Patent ID: 9671373
Date: 2017-06-06
CPC Classifications: F28F,G01N,G06Q,H01L,H04R

Claim:
1. A method of testing a heat exchanger tube for defects, the method comprising: generating a longitudinal elastic guided wave of a selected frequency and mode with a magnetostrictive transducer assembly; guiding the elastic guided wave into an open end of the tube; sensing a reflection of the elastic guided wave from a defect in the tube; measuring a time duration between generation of the elastic guided wave and the sensing of the reflection of the elastic guided wave; and determining a location of the defect in the tube based on the measured time duration, wherein the longitudinal elastic guided wave is generated with a magnetostrictive transducer assembly placed in the open end of the tube, the magnetostrictive transducer assembly comprising a current-carrying coil of wire, a magnetostrictive material wrapped around the coil of wire, a mechanism for pressing the magnetostrictive material against an inner surface of the tube, and one or more biasing magnets placed in the vicinity of the current-carrying coil of wire and the magnetostrictive material.