DB21/T 2170.2-2013 采暖塑料管管道工程技术规程 第2部分：无规共聚聚丙烯（PP-R）塑铝稳态复合管管道、纳米复合四型 聚丙烯（NFβPP-R）管管道、无规共聚聚丙烯（PP-R）管管道、聚丁烯（PB）管管道

DB21/T 2170.2-2013 Heating Plastic Pipe Pipeline Engineering Technique Regulations Part 2: Random Copolymer Polypropylene (PP-R) Plastic Aluminum Stable Composite Pipe Pipeline, Nanometer Composite Four-Type Polypropylene (NFβPP-R) Pipe Pipeline, Random Copolymer Polypropylene (PP-R) Pipe Pipeline, Polybutene (PB) Pipe Pipeline