Electron Beaming of Large Diameter Thick-Walled PE Pipes [PE]

The crosslinking of polyethylene by irradiation is a well known technology in the sanitary and heating pipe market. For more than 20 years PE-Xc-pipes in dimensions up to about 40 mm and wall thicknesses up to about 4 mm have been used successfully in this market. With the development of a new crosslinking technology by irradiation in combination with higher energy of electron accelerators (10 MeV) the crosslinking of polyethylene pipes has been extended up to a diameter 450 mm, wall thickness 40 mm and lengths of 12 m. The crosslinking of large diameter, thick walled polyethylene pipes has become possible with the development of new technology using the interaction of irradiation energy together with improved pipe transport under the irradiation field. The construction of a new irradiation plant with such a new pipe transport system at Radeberg in Germany enables pipes up to 12 m in length to be crosslinked by electron irradiation. Investigations have been carried out on PE-Xc pipes produced in this way. A general overview of large diameter PE-Xc pipe properties is presented including the excellent resistance to crack growth. This technique will enable the range of PE-X for gas and water pipes as well as pipes for industrial applications to be increased.