Nomura, Hirabayashi, Troughton
New Products & Site Techniques # 1998 Gothenburg
This paper describes an assessment of the quality of butt and branch joints in polyethylene (PE) pipes, produced using the linear vibration welding technique. Results showed that butt welds in pipes of 165 mm outside diameter(0D) could be produced within a total weld/cool time of 85 seconds, which is less than 15?'0 of the time required for butt fusion welding equivalent sized pipes in the field. The mechanical properties of the linear vibration welds were determined using tensile, impact and creep rupture tests. and results indicate that these joints are at least as good as current butt fusion welds. Pipe branches could also be made by the linear vibration technique by simply welding two pipes together at right angles. The resulting welds were stronger than the parent branch pipe. Based on these results, a prototype portable linear vibration welding machine has been developed in order to construct PE pipeline in the fields.