Tag Archives for Shear Wave
Shear Wave UT – Applications and Limitations
UT is a very efficient NDE method. A large amount of data for evaluating the integrity and reliability of a vessel can be obtained in a relatively short period of time, without requiring extensive preparation of the vessel or interfering … Continue reading
Shear Wave UT – UT Imaging
UT imaging can be used to obtain two- and three-dimensional pictures of cracks, or other types of flaws, in a pressure vessel component from an automated ultrasonic examination. An ultrasonic transducer (either longitudinal or shear wave) is moved over the … Continue reading
Shear Wave UT – Time Based Sizing
Time based sizing generally provides greater accuracy for determining depth, especially when the crack is relatively small with respect to the diameter of the transducer. Therefore, time based sizing should be used whenever a fitness-for-service analysis is made to evaluate … Continue reading
Shear Wave UT – Amplitude Based Sizing
Figure 700-20 illustrates how the depth of a crack is determined using amplitude based sizing techniques. The crack was detected by shear wave UT as shown in Figure 700-19. The occurrence of a relatively high amplitude peak in the oscilloscope … Continue reading
Shear Wave UT – Crack Sizing
The ability to determine the depth of a crack through the thickness of a vessel shell is a very important attribute of shear wave UT. However, the accuracy of the depth measurements made with UT can vary considerably, depending on … Continue reading
Shear Wave UT – Crack Detection
Shear wave UT is very useful for detecting cracks that have developed during service. Figure 700-19 illustrates how shear wave UT, calibrated according to Figure 700-18, can be used to detect a crack in the heat affected zone of a … Continue reading
Shear Wave UT – Calibration
Shear wave UT is calibrated using a test block manufactured from a material similar to the workpiece (i.e., with the same velocity of sound), that has side-drilled holes and a notch on the back surface as shown in Figure 700-18. … Continue reading
Shear Wave UT
Shear wave UT is used primarily to detect and determine the size of cracks that have developed during service. Forms of deterioration that can result in cracking include mechanical and thermal fatigue, creep, stress-corrosion, and hydrogen attack, among others (see … Continue reading