关于氧气管道阀门安装,如何翻译? the main pipe material shall be made of stainless steel (or material having a higher exemption pressure) upstream (if there is no check-valve) and downstream the isolation valve up to one dn passed the by-pass branch connections, 在截止阀的上下游,旁通支管路接头一个dn长度范围内,主管材质应采用不锈钢(或许用压力更大的其他材质)。 fyi查看更多