Webinars
03 June 2026
Joint Industry Project Launch Meeting on Production of Flawed Butt Fusion Joints in PE Pipes for the Evaluation and Qualification of Ultrasonic NDT Systems
The industrial interest and use of ultrasonic non-destructive testing (NDT) of butt fusion (BF) joints in polyethylene (PE) pipes is rapidly gaining momentum, due to the publication of the ISO Technical Specifications ISO/TS 22499 and ISO/TS 24399, and the increasing number of companies providing such as service.
However, the ultrasonic inspection of PE pipe joints is very different to the inspection of metallic pipe joints. The attenuation of the ultrasonic signal is much greater in PE than in metals, the velocity of the ultrasound is much slower and the types of flaws are very different to those found in metal joints. This means that ultrasonic NDT systems used to inspect metallic pipe welds will not work on PE pipes; the ultrasonic probes, wedges, manipulators and procedures have to be designed specifically for non-metallic pipes.
For the pipeline owners, it can be difficult, and costly, to assess the performance of any particular NDT provider. The procedure for qualifying NDT procedures in ISO/TS 22499 and ISO/TS 24399 involves making 21 BF joints for each of four pipe wall thicknesses ranges. Five joints should contain no flaws and are used by the NDT provider to set up their equipment and procedures. The remaining 16 joints are used for blind inspections. Eight of these contain no flaws, two contain embedded lack of fusion flaws and six contain fine particulate contamination.
The production of these joints is expensive, which makes it cost-ineffective for individual companies to produce such a set of joints, especially if they need to cover the whole pipe wall thickness range from 8-100mm, which would require the manufacture of 84 joints. It is therefore more efficient for there to be a central library of flawed joints that companies can borrow as and when they need.
TWI is a world leader in the insertion of flaws into welded joints in PE pipes in a consistent manner and wrote the flaw insertion procedures given in the annexes of the ISO Technical Specifications. TWI is therefore ideally placed to create and hold this library of flawed joints.
This launch meeting will be hybrid.
If you would like to find out more or express an interest in any of these proposed projects, you can email Sofia Sampethai at sofia.sampethai@twi.co.uk
Find out more about the TWI Joint Industry Project Programme
Speakers
Sofia Sampethai
Joint Industry Programme Manager
TWI
Sofia is Joint Industry Project Manager at TWI in the Business Develoment section. She is a Chartered Engineer and a Member of the Welding Institute. She has studied Chemical Engineering and her MSc was carried out at ETH Zurich in the department of Process Engineering. Sofia manages funded collaborative projects, including Innovate UK, FP7 and H2020, and the majority of them are in the areas of condition monitoring, sensor development targeting composites failure, and integrity monitoring for casings used in oil and gas industry. She has also been involved in proposal writing for European and national funded projects, and in developing partnerships within industry. Sofia’s work is focused on the research and development of innovative solutions in the area of condition and structural health monitoring.
Mike Troughton
Technology Fellow for Polymer Welding
Mike has been carrying out research for the plastics industry for over 35 years. His main areas of expertise include the welding, inspection and mechanical testing of PE pipes, on which he has written over 30 technical papers. He is also the editor of the Handbook of Plastics Joining – A Practical Guide. He has managed over 150 research projects for clients all over the world and is the UK representative on various ISO, CEN, BS, IIW, AWS and ASME committees on the welding of plastics and plastics pipes.