LRUT using guided waves is different from conventional ultrasonic inspection.
An important point to note is that LRUT techniques do not provide a direct measurement of pipe wall thickness, but are sensitive to a combination of the depth and circumferential extent of any metal loss.
Since LRUT is a volumetric exam the probability of detection would trot change if reconfigured to five areas whose sum equaled the original area of 0.
The following list summarizes the applications that were tried and found within the capabilities of the LRUT technique using the Teletest[R] system:
The LRUT method is adept for these surveys because it reduces pipe access costs, especially in overhead piping and pipe racks.
Pipeline inspections using LRUT were more problematic than those conducted on aboveground piping whether insulated or not.
The use and ultimate success of LRUT techniques, irrespective of equipment manufacturer, is largely dependent on the training and field experience of the technician.