Defects Detection System for Steel Tubes Based on Electromagnetic Acoustic Technology

Based on the electromagnetic acoustic technology (EMAT), a system for detecting the defects of steel tubes has been constructed. Through analyzing the principle of detecting the defects of steel tubes by EMAT, an electromagnetic acoustic transducer is designed to transmit and receive the electromagnetic acoustic signals. After the data are acquired by the high-speed data acquisition card, they are transferred to computer and are processed. In addition, theselective frequency and amplification technology was used to process the weak received signal, which improved the anti-jamming ability of the system. Experimental results of different diameter through-hole steel tubes showed that this system can automatically detect the defects in steel tubes.