Abstract: A method for the ultrasonic testing of disc bodies, shrunk onto shafts, is especially adapted for testing the shrink-fitted seats thereof adjoining the shafts and usually is provided with anti-rotation holes containing anti-rotation inserts. Such disc body arrangements are often used in the field of low pressure turbine rotor disc fastenings. The method is carried out by using ultrasonic angle beam probes operating according to a method of corner reflection or transversal waves within the range of critical angles of total reflection, or according to a method of grazing incidence. Both methods can be used as a pulse echo technique, or as a tandem technique. The probes are coupled to the curved side walls of the discs for following test patterns extending in circumferential direction of the disc bodies. Ultrasonic sound beams emanating from the probes are aligned toward the test regions of the inner surfaces of the hubs. Three axially adjacent test regions are tested.

Abstract: A special angle beam probe for ultrasonic testing includes at least one ultrasonic vibrator fastened in a beam probe housing on a wedge-shaped support body which may be formed of Plexiglass, using damping means. The ultrasonic beam of the vibrator strikes the surface of the test piece at an incidence angle other than 0.degree., as measured from a perpendicular at the surface of the test piece at the point where the beam strikes. The ultrasonic beam furthermore strikes the test piece surface at an oblique angle between 0.degree. and 360.degree. subtended between a principal beam probe axis and the beam, as seen in the direction perpendicular to the beam probe from above. The novelty of the invention is that the special angle beam probe includes a multiplicity of prefabricated beam probe subassemblies. The ultrasonic vibrator of each subassembly is fastened with a predetermined incidence angle within a first beam probe housing.