A Virtual Instrument For Performance Evaluation Of Ultrasonic Examination Instruments

Non-destructive test is an important way to ensure industry safety and improve quality of products. Ultrasonic examination equipment is used widely as a non-destructive test equipment. Any non-destrutive test equipment must be tested strictly before being used, so that its reliabilty can be ensured. New national and international evaluation standards introduce more test items and more test methods than before. While there are still old test way, so low efficiency and great subjective errors exist. It is necessary to improve effiency and precision, so to adapt new standards.In this paper, stardards of EN,ISO and ASTM are analyzed firstly, and a scheme based on virtual instrumen is designed. Then the design and selection of hardare in the scheme are finished, main parameters of the signal generator and data acquisition card are analyzed as a key factor, a intergrating circuit is designed to solve problem of synchronization trigger. At last, software of the system is finished, which includes design of program structure, control of hardware, general design of program and test program design of key parameters. Vertical linearity and horizonal linearity, temporal resolution and transmitter pulse, which is key parameters of ultrasonic examination equipment, are analyzed particularly and their test way is introduced.Uncertainty of test result about key parameters are computed, which shows that the perfomance evaluation system based on virtual instrument can meet the requirment of the new standards. The test system is also convenient, rapid and precise.