BS EN 15698-2:2025

District heating pipes. Bonded twin pipe systems for directly buried hot water networks. Factory made fitting and valve assemblies of steel service pipes, polyurethane thermal insulation and one casing of polyethylene | Status: Current

1 Scope This document specifies requirements and test methods for fitting and steel valve assemblies of factory made thermally insulated bonded twin pipe assemblies for hot water networks in accordance with EN 13941‑1, comprising two steel service pipes, in most cases steel fittings and/or steel valves, steel components, polyurethane (PUR) foam thermal insulation and one casing of polyethylene.

NOTE Steel components can be e.g. fixing bars.

The twin pipe assembly can also include the following additional elements: measuring wires, spacers and diffusion barriers. This document covers the following assemblies:

• — fittings: bends, T-pieces and reducers;
• — valves for main line.

This document applies to fitting assemblies with an internal pressure of at least 1,6 MPa and steel valve assemblies with a maximum internal pressure of 2,5 MPa.