| 摘要 |
<p>A method of locating reflectors for non-destructive testing using ultrasonic pulses and pulse transition time or echo measurement enables accurate location of reflectors whose separation is small compared to their distance from the instrument. For each location procedure the workpiece surface (4) is scanned from two or more points whose coordinates (P1,P2,P3) are measured or predefined. The test head orientations and location distances (R1,R2,R3) are measured. The location of the reflector is defined as a volume (4) which is derived from the measured parameters. Construction of the volume involves the use of known, calculated, or estimated tolerance and deviation values for test head position and orientation and distance measurement. Alternatively, each point may be defined as a volume derived from measurements by two or more heads moving on a given path.</p> |
