Longitudinal wave UT is used primarily to determine the remaining thickness of corroded shell components, including the depth of pits. It can also be used…
Category: In-Service Inspection
Attenuation of ultrasonic waves propagating through air is very high, and normal surface roughness (especially of the workpiece) will always create an air gap between…
Ultrasonic waves for UT are created in a metal workpiece with a piezoelectric transducer that is coupled to the workpiece. The piezoelectric transducer converts high…
Most UT systems used for the in-service inspection of a pressure vessel employ a “pulse-echo” method of operation, in which the same transducer (described below)…
A high-frequency sonic (referred to as “ultrasonic”) wave is introduced into a solid material and is reflected by interfaces in the material. The reflected waves…
UT is a very versatile NDE method. A variety of techniques have been developed for using UT to detect most forms of deterioration that can…
MT is preferred to PT for detecting surface cracks because of its greater sensitivity, especially when wet particles are used. Very fine cracks can be…
The magnetic particles that are applied to the surface of a workpiece when it is magnetized are of two types, dry and wet; and they…
The electric current for magnetizing the workpiece, with either an electromagnetic yoke or electric prod contacts, must be flowing to produce strong magnetic lines of…
The MT systems used for in-service inspection of pressure vessels employ an electric current to magnetize the area of the vessel shell being examined. Either…