Tue, 09 December, 2025
TWI is launching a Joint Industry Project (JIP) to assess the use of ultrasonic testing in lieu of radiographic testing by industry.
Significant benefits can be realised by switching from radiographic to ultrasonic inspection, including cost savings and improved health and safety. Radiographic inspection includes a number of health and safety implications due to the need to work with ionising radiation. In addition, radiographic inspection requires exclusion zones, which prevent other work from being performed in the same area as the radiography as well as the additional staffing required to maintain any exclusion zones.
The advancement of ultrasonic testing techniques like phased array ultrasonic testing (PAUT) and full matrix capture (FMC) / adaptive total focusing method (ATFM) has allowed us to develop client and component-specific inspection techniques that reduce the need for radiographic inspection.
However, ultrasonic inspection is yet to replace radiographic inspection due to limitations with current inspection techniques on complex joint configurations, where the removal of weld caps is required to achieve full coverage of the weld volume for ultrasonic testing, which is not required with radiographic inspection. The ability to run tests with the weld caps in place avoids additional machining and preparation costs.
Our new joint industry project, ‘UT in lieu of RT: Guidance and Validation of Through Cap Inspection of Welds with Intact Caps,’ will seek to develop techniques and procedures for ultrasonic inspection of complex configurations using AFTM with the weld cap in place. Lessons learnt from this project will be used to create industry guidance on the ‘design for manufacture and inspection’ of complex geometries across the entire life cycle of components. This research will consider factors such as welding process, joint configuration and weld cap profile, as well as how they impact the ability to perform weld scanning with the cap intact.
Inspection trials will be performed on a range of test samples with different geometries and artificial flaw types, some of which will be produced to match the needs and interests of the project sponsors. In addition, the project team will test samples from genuine components provided by the sponsors from actual structures.
ATFM through weld cap inspection techniques/procedures will be developed and validated for the test samples under consideration before the lessons learnt from this work are used to produce a best practice guide covering ‘Design for Manufacture and Inspection’ for complex geometries and the entire life cycle of the component. This guide will consider factors such as welding process, joint configuration and weld cap profile, and how they impact the ability to perform through weld scanning.
You can find out more about the key objectives and benefits of this project, as well as how you can get involved and gain from this exclusive project work, here:
https://www.twi-global.com/what-we-do/research-and-technology/research-programmes/joint-industry-projects/ut-in-lieu-of-rt-guidance-and-validation-of-through-cap-inspection-of-welds-with-intact-caps