This document specifies requirements and test methods for factory made thermally insulated flexible pipe-in-pipe assemblies for directly buried district cooling distribution systems, comprising a service pipe and a casing of polyethylene. The pipe assembly can also include the following additional elements: measuring wires, spacers and diffusion barriers.
This document is intended to be used in conjunction with EN 17414-2 or EN 17414-3.
This document applies only to insulated pipe assemblies, for continuous operation with water at various temperatures (1 to 30) °C and a maximum operation pressure of 25 bar dependent on material specified.
The design is based on an expected service life with continuous operation of a minimum 50 years. For pipe systems with plastic service pipes, the respective temperature profiles are defined in EN 17414-2 and EN 17414-3.
NOTE For the transport of other liquids, for example potable water, additional requirements could be applicable.