... ptroleum craking,chemical fertilizer equipment,high pressure boiler,low & mid-pressure boiler,etc.Stainless Steel Pipe300 SeriesGB,JIS,ASTM, ... 19990.5-200mm, 6-1240mmUsed in general and mechanical structure Alloy Steel PipeDin2391 17 Cr3, ST52, A335P11,P5,P910,P22, ... in chemical equipment,fertilizer equipment and pipelines under high pressure or high tempretureOil casing pipeAPI J55, API K55, API L80 ...