EN 253:2009 区域供热管.直接铺设在地下的热水管路用预绝热复合管系统.由钢管,聚胺酯隔热和和聚乙酰外壳制成的复合管系
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 (Incorporates Amendment A1: 2013)