ULTRASONIC NON-DESTRUCTIVE TESTING OF TUBES AND RODS

摘要

1413755 Ultrasonic inspection devices KRAUTKRAMER GmbH 2 March 1973 [2 March 1972] 10325/73 Heading H4D Ultrasonic inspection apparatus for testing a rod or tube includes two probes mounted as a rigid unit with the probe beams intersecting. Each probe acts as both transmitter and reciever for testing the rod or tube; additionally, one probe acts as transmitter and the other as a receiver of waves reflected from the rod or tube surface for checking the position of the beam intersection point relative to the surface. The probes, whose beams lie in a cross-sectional plane through a tube or rod being inspected and can be adjusted to intersect at the outer surface of the tube or rod, are used in a pulse-echo inspection mode in a four-part sequence. In the first part a first probe acts as transmitter for propagating transverse waves clockwise round the rod or tube and receives flow echoes; in the second part the correct setting and functioning of the probes is monitored by using one as a transmitter and the other as an echo receiver; in the third part the second probe is used as transmitter and receiver for transverse waves propagated anti-clockwise; in the fourth part monitoring is done as in the second part but with the roles of the two transducers reversed. The correct distance of the probes from the surface of the tube or rod can be set for different diameters of rod or tube by monitoring on an echo-indicator screen the transit time of the surface echo. Further probe pairs may be used.