TWI has been providing non-destructive testing (NDT) services for decades; supporting a range of industry sectors, delivering research and development of NDT technologies, processes and inspection services, as well as providing high quality NDT inspection services in conventional, advanced and automated techniques.
Our work helps ensure that equipment, plant assets and products remain operational, reliable and safe, while our team of highly skilled NDT consultants, engineers and technicians, and our wide range of industrial facilities and tools place us in a unique position to solve the NDT problems of Industrial Member companies.
Having delivered a range of NDT projects for industry for over 40 years, our experts have worked across all industry sectors. These projects include those dedicated to improving NDT processes, core research projects on the behalf of our wider Industrial Membership, joint industry projects to meet the needs of interested groups of sponsor companies, projects on behalf of specific organisations, and collaborative projects working alongside other organisations to meet wider goals.
All of this work has fed into our expertise and experience, allowing us to take solutions from one industry and apply them to others, while remaining independent and impartial. As the following examples demonstrate, TWI’s years of experience in NDT has crossed a range of industries, providing bespoke solutions, support and advice, while also advancing techniques for the benefit of industry as a whole:
- Novel Focused Ultrasonic Transducers for NDT
A study dating back to 1986 details work undertaken at TWI into the use of Axicon and toroidal focusing elements to improve the beam characteristics of ultrasonic transducers used in NDT. This research delivered a new method for characterising these focusing elements and new possibilities for transducer design - without overly altering existing manufacturing techniques for mass-produced, commercially available unfocused transducers - thereby opening up the possibility of wider exploitation within the NDT industry.
- Ultrasonic/Radiographic NDT of Fusion Weld Polyethylene Pipe
By 1996, our expertise in advancing NDT had turned towards the ultrasonic and radiographic non-destructive testing of fusion weld polyethylene pipe. The use of polyethylene (PE) pipe had seen a significant rise in the water and gas industries due to its corrosion resistance, light weight, flexibility and ease of joining. While pipes of less than 250mm in diameter were typically joined through electrofusion, larger pipes and those with thicker sections tended to be hot plate butt fusion welded. However, as new polyethylene materials were introduced (e.g. PE100) and increased demands were placed on existing polyethylene materials, there was an additional need to monitor quality through reliable NDT methods, which opened up a route towards creating nationally accepted standards for NDT of welds in polyethylene.
- Smart Condition Monitoring and Prompt NDT Assessment of Large Concrete Bridge Structures
Around the same time as our experts were investigating PE pipes, we were also involved in the CROSS-IT project, which was funded by the European Commission to develop a new technology, based upon ultrasonic guided waves, to inspect the levels of age-related degradation caused by water to the concrete structure and steel reinforcements of large bridge structures. The aim was to assess how water ingress into surface cracks could result in dangerous levels of corrosion in internal steel re-bars and reinforcements.
- Continuous Reliable Advanced Novel Efficient Structural Health Monitoring System for Crane Inspection Applications
Also funded by the European Commission, the CRANEInspect project allowed us to contribute our expertise to a different area of structural health, with the development of an advanced, integrated structural health monitoring system to continuously monitor cranes in industrial, logistics, construction, and shipbuilding sites. The new and novel techniques and sensor systems were created to inspect for structural damage or cracks in the main frame caused from fatigue, distortion, corrosion, etc., and to provide real time information about the condition of the structure.
- The On-line Control of Friction Stir Welding Processes using Ultrasonic Test Techniques
As well as developing new methods for assessing structural integrity, we have also turned our attention to using NDT to control different processes. The Innovate UK-funded FrictionHarmonics project aimed to develop a prototype, non-linear, high frequency ultrasonic NDT system for the in-process inspection of friction stir welds in aluminium, nickel alloys, titanium and steel structural components. The project was created to detect manufacturing defects, including ‘kissing bond’ defects, and then provide feedback software to the friction stir welding (FSW) process control to eliminate the further introduction of the detected manufacturing defect(s). This project shows how we bring together different areas of expertise for the benefit of industry, using not just our technical excellence in NDT, but also our knowledge of software and our longstanding experience with FSW, which was invented at TWI in 1991.
- Non-Destructive Testing of Thermally Sprayed Coatings
Our knowledge of NDT methods was also used in 2000 to test thermally sprayed coatings, which were increasing in their application across industry for the enhanced properties they offer, including wear and corrosion resistance. However, any benefits depend upon the quality of the coating, and so, this NDT spray coating research project sought to provide a review of all NDT methods suitable for the inspection of thermally-sprayed coatings and allow for coating quality to be assessed in actual components rather than just in small test coupons.