SA-210C(25MnG):是ASME SA-210標準(zhun)中(zhong)的鋼(gang)(gang)號,是鍋爐(lu)和(he)過熱(re)器(qi)用(yong)(yong)碳錳(meng)鋼(gang)(gang)小口(kou)徑無縫(feng)鋼(gang)(gang)管,珠光體型(xing)熱(re)強(qiang)鋼(gang)(gang)。我國(guo)于1995年(nian)將(jiang)其(qi)移植到(dao)GB5310,定名為25MnG。其(qi)化學成(cheng)分簡單,除碳、錳(meng)含量(liang)較高外,其(qi)余與(yu)20G相近,故其(qi)屈服強(qiang)度較20G高約20%左(zuo)右,而塑、韌性則與(yu)20G相當。該鋼(gang)(gang)的生產工(gong)藝簡單,冷熱(re)加工(gong)性能好。用(yong)(yong)其(qi)代替20G,可以減薄壁厚,降低材料(liao)用(yong)(yong)量(liang),還可以改(gai)善鍋爐(lu)的傳熱(re)狀況。其(qi)使(shi)用(yong)(yong)部(bu)位和(he)使(shi)用(yong)(yong)溫(wen)(wen)度與(yu)20G基本相同,主(zhu)要用(yong)(yong)于工(gong)作溫(wen)(wen)度低于500℃的水冷壁、省煤器(qi)、低溫(wen)(wen)過熱(re)器(qi)等部(bu)件。