NF EN 253

District heating pipes - Bonded single pipe systems for directly buried hot water networks - Factory made pipe assembly of steel service pipe, polyurethane thermal insulation and a casing of polyethylene

Le présent document concerne les réseaux de chauffage urbain enterrés directement. Il définit les exigences et les méthodes d'essai applicables aux longueurs droites d'assemblages de tubes isolés thermiquement comprenant un tube de service en acier de DN 15 à DN 1200, une isolation en mousse rigide de polyuréthane et un tube de protection en polyéthylène.

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