一般保温2小时，没有时间越长硬度越低一说17，AMS5643，ASTMA564和ASTMA693Grade63017。GH4169无缝管GH4169钢板GH4169圆钢GH4169锻件GH4169法兰GH4169圆环GH4169焊管GH4169钢带GH4169直条GH4169丝材及配套焊材GH4169圆...