Guided Wave Testing (GWT) is now a standard Non-Destructive Testing (NDT) method to inspect pipework in many industrial disciplines, such as oil and gas, petrochemical and power generation sections. The torsional guided wave mode is highly sensitive to most defect types while experiencing low attenuation in most situations. In the majority of the applications, this mode is ideal for the inspections of a long length of pipework. Welds, supports, defects, and other features generate echoes from which their locations and severities (in the case of a defect) can be measured. The data is usually analysed on-site so that any follow-up or complementary inspections can be performed immediately.

An inspection is done by wrapping a removable transduction ring around the circumference of the tube/pipe at the desired location, which can be many meters away from the region of interest. Force is applied, either mechanically or pneumatically, to the transducers to obtain good coupling. The signals are generated and received using our state-of-the-art electronics unit, the Wavemaker®, which is then processed by the WavePro Software using an advanced processing algorithm. The results are presented in a user-friendly GUI, which allows the inspector to report the data.

The interpretation of the results can be the most challenging part of this technology. As such, GUL has a comprehensive training programme of different operator levels targeting specific GW applications. More information can be found on the Training Page.

Inspection Equipment

Specialist Inspection