ASTM F1973-21
聚乙烯(PE)、聚酰胺11(PA11)和聚酰胺12(PA12)燃气分配系统中工厂组装的无阳极竖管和过渡配件的标准规范
Standard Specification for Factory Assembled Anodeless Risers and Transition Fittings in Polyethylene (PE) and Polyamide 11 (PA11) and Polyamide 12 (PA12) Fuel Gas Distribution Systems