1 high tention and good quality 2 black carbon steel pipe manufacture 3 widely use in many ways 4 ... GB,JIS,ISO,ASTM,BS,DIN the black carbon steel pipe is widely use in conveyor belt transmission,machine ... in: construction,fence,structural tube,window section and other parts ,frame, shelf,etc Executive StandardGB-13793-1992 BS1387 ASTM A53 ASTM ...