HG 20225《化(hua)工(gong)金(jin)屬(shu)(shu)管(guan)(guan)(guan)道(dao)(dao)工(gong)程施工(gong)及驗(yan)收(shou)規(gui)范》規(gui)定化(hua)工(gong)行(xing)業金(jin)屬(shu)(shu)管(guan)(guan)(guan)道(dao)(dao)應按管(guan)(guan)(guan)道(dao)(dao)所輸送(song)的介(jie)質分為(wei)四類：A類為(wei)輸送(song)劇毒介(jie)質的管(guan)(guan)(guan)道(dao)(dao)；B類為(wei)輸送(song)可(ke)燃介(jie)質或有(you)毒介(jie)質的管(guan)(guan)(guan)道(dao)(dao)；C類、D類為(wei)輸送(song)非(fei)可(ke)燃介(jie)質、無毒介(jie)質的管(guan)(guan)(guan)道(dao)(dao)。其中設計(ji)壓(ya)力p≤1MPa，且(qie)設計(ji)溫度為(wei)-29～186℃的管(guan)(guan)(guan)道(dao)(dao)為(wei)D類管(guan)(guan)(guan)道(dao)(dao)。

   注意：混合物料(liao)應以其主導物料(liao)作為分級依據。常見劇(ju)毒(du)介質、可(ke)燃介質或有(you)毒(du)介質，請參考(kao)《化工(gong)金屬管道工(gong)程施(shi)工(gong)及驗收(shou)規范》的附錄。