Based on the investigation of the existing problems in ultrasonic inspection of large cylindrical parts,an online and automatic ultrasonic testing system was developed to detect the inner flaws of lager cylindrical parts. The system includes a ultrasonic transducer and fixture equipment, a set of supplying and recycling couplants，a high speed transmitting and receiving ultrasonic A/D card based on PCI bus, a laptop computer fro factories, a software system , a location sensor and so on. The function of the system is to receive and process the ultrasonic signals, store testing data, and online analyze and recognize inner flaws. Through the application of the factory, the system is proved to be available for diagnosing the defects of the large cylindrical parts.
