摘要 |
Multi-channel automatic on-line ultrasonic inspection system for real time high-speed pulse echo testing is done across the width of a hot moving workpiece, such as steel plates and the like. In addition to a multiplexed transducer array search unit, the system includes an adjustable ultrasound fluid couplant, a main ultrasonic instrument modified with a digital multi-channel R.F. attenuation controller and a digital automatic flaw gate controller combined as on-line calibration means. The calibration means automatically corrects echo pulses for attenuation errors due to effects of variations in workpiece alloy or composition and temperature, and timing errors due to effects of variations in thickness and transducer gap, respectively. System further includes an ultrasonic data buffer/controller (UDBC) for digitizing, encoding and storing corrected or uncorrected flaw area data passed by the flaw gate during workpiece movement. The UDBC, together with a process control minicomputer, a display terminal and printer, provides computer-aided flaw area detection and reconstruction with printouts of an encoded flaw map and an A.S.T.M. flaw evaluation.
|