The process involves scanning the surface of the material around the weldment with the transducer. This refracted sound wave will bounce off a reflector ( discontinuity) in the path of the sound beam. Will proper angle beam techniques, echoes returned from the weld zone may allow the operator to determine the location and type of discontinuity.
To determine the proper scanning area for the welder,the inspector must first calculator the location of the sound beam in the test material. Using the refracted angle, beam index point and material thickness, the V-path and skip distance of the sound beam is found. Once they have been calculated, the inspector can identify the transducer locations on the surface of the material corresponding to the Crown, side wall,and root of the weld.