用于非开挖替换地下管线网络的塑料管道系统第2部分:通过水平定向钻孔和冲击模锻在线下更换

[中文适用范围]： 本文件规定了用于非开挖更换各种地下管网、地下无压和有压排水和排污管网以及地下供水和供气管网的塑料管道系统中管材和管件的要求和试验方法，更换方式为使用水平定向钻孔和冲击成型。它适用于制造的聚乙烯 (PE) 管道和管件以及已安装的更换系统。本文件旨在与适用于 PE 管道系统建设的标准结合使用。对于制造的管道，它适用于三种不同的 PE 管道类型： - PE 实壁单层管（公称外径，dn），包括任何识别条； - 管道内外任一或两侧均有共挤层的 PE 管道（总外径，dn），如附件 A 所述，其中所有层均具有相同的 MRS 等级； — PE 管（外径，dn）在管外部具有可剥离的连续热塑性塑料附加层（“涂层管”），见附录 A。此外，它还适用于： — 在安装前通过对接熔接接头连接管道长度以形成连续的管串； — 由 PE 制成的装配和注塑配件。由其他塑料（例如聚丙烯 (PP)）制成的管道不在本文件的范围内。本文件不适用于作为非开挖安装过程的一部分组装的推入式连接离散管道。 [外文原描述]： ISO 21225-2:2018 specifies requirements and test methods for pipes and fittings which are part of plastics piping systems for the trenchless replacement of various underground pipeline networks, underground non-pressure and pressure drainage and sewerage networks and underground water and gas supply networks, by means of horizontal directional drilling and impact moling. ISO 21225-2:2018 is applicable to polyethylene (PE) pipes and fittings, as manufactured, as well as to the installed replacement system. ISO 21225-2:2018 is intended to be used in conjunction with standards applicable for the construction of PE pipeline systems where available. Regarding manufactured pipes it is applicable to three different PE pipe types: - PE solid wall single layered pipes (nominal outside diameter, dn), including any identification stripes; - PE pipes with co-extruded layers on either or both the outside and inside of the pipe (total outside diameter, dn), as specified in Annex A, where all layers have the same MRS rating; - PE pipes (outside diameter, dn) having a peelable, contiguous, thermoplastics additional layer on the outside of the pipe ("coated pipe"), see Annex A. In addition, ISO 21225-2:2018 is applicable to: - jointing of pipe lengths by means of butt fusion joint to form continuous strings prior to installation; - fabricated and injection-moulded fittings made of PE. Pipes made from other plastics, e.g. polypropylene (PP) are outside the scope of this document. ISO 21225-2:2018 is not applicable to push-fit jointed discrete pipes assembled as part of the trenchless installation process.