Abstract: Device for nondestructive ultrasonic testing of cylindrical parts, comprising a basin in which the part to be tested, for example a journal bearing provided with an antifriction alloy is immersed. The basin is mounted on a revolving plate having a gear driven by means of an inclined-tooth pinion. A vertically movable horizontal arm, depending upon diameter of the part to be tested, carries two piezoelectric transducers and an arcograph, the marking of the bonding fault area on the surface of the part to be tested being effected by means of an electric arc produced between one trace element of the arcograph, which receives a voltage signal from the monitor of a fault detector through the control assembly of the arcograph, and the inner surface of the part to be tested. The entire cylindrical surface is explored along a tangent of partially superposed helixes and the pitch of the helix is equal to, or smaller than the diameter of the piezoelectric transducer crystal.