Historical
DIN EN 253:2013
District heating pipes - Preinsulated bonded pipe systems for directly buried hot water networks - Pipe assembly of steel service pipe, polyurethane thermal insulation and outer casing of polyethylene; German version EN 253:2009+A1:2013 (Foreign Standard)
This European Standard specifies requirements and test methods for straight lengths of prefabricated thermally insulated pipe-in-pipe assemblies for directly buried hot water networks, comprising a steel service pipe from DN 15 to DN 1200, rigid polyurethane foam insulation and an outer casing of polyethylene. The pipe assembly may also include the following additional elements: measuring wires, spacers and diffusion barriers.This standard applies only to insulated pipe assemblies, for continuous operation with hot water at various temperatures up to 120 C and occasionally with a peak temperature up to 140 C.The estimation of expected thermal life with continuous operation at various temperatures is outlined in Annex B.
Deutsches Institut für Normung [din]