New technology for quality assurance of PE-pipelifes

Purpose and goal

The goal was to develop quality assurance of joint methods for polyethylene pipes. We have through the procurement pushed the development forward on non-destructive testing for butt welds, electro fusion welds and saddle welds. The project also included the development of requirements for electro fusion welds needed for quality insurance. The work has shown that the simulation of the electro fusion welds failure mode is very complicated, but the project have contributed to better definition of our requirements.

Results and expected effects

The result of the project have contributed to the identification of four possible suppliers of non-destructive testing of PE pipes. All methods are note suitable for finding all different faults that can occur when joining PE pipes. Ultrasound is suitable for butt welds. For electro fusion welds and for saddles both x-ray and ultrasound are suitable to find the faults. The project have also resulted in information that will change our requirements on the suppliers and future work will focus on developing standards for NDT.

Approach and implementation

The project´s approach has been successful with that suppliers have first developed the concept study, and then carried out field tests. One lesson is that the field test could have been two days per method instead of one. We could also have had more fabricated faults for the suppliers to try to identify. It had also been good to perform the test on several different geometries of saddles and electro fusion welds to investigate how the different technologies work there.