The inspection is performed from the nut side with the use of the spanner-like delay line, which is applied to the bolt end with the use of coupling gel. The opposite side of delay line is manufactured in the form of hollow cylinder, which’s bottom is covered by the coupling media as well. The cylindrically shaped probe holder containing a slot for the reduced contact face PA probe is placed inside the delay line’s cup providing the correct positioning of the probe.
The inspection is performed with the use of portable PA instrument of ISONIC series (ISONIC 3510, 2010, 2009 UPA Scope) running the EXPERT-SHAFT application through the guided circumferential sliding of the probe above the delay line performed upon the PA Pulser receiver is calibrated and the dimensions of the bolt have been entered. The true-to-geometry intuitively interpretable imaging is provided. When necessary the complete revolution data may be recorded and presented in the form of C-Scan or 3D-image. The video of the process illustrating the scanning of the performance demonstration block is shown below: