... ASME B16.9, API 5L, ASTM A106/A53, DIN 3: ISO9001 ASTM A53 hot-rolled seamless steel pipe Specification Typehot-rolled seamless steel pipe ASTM A 53 Pipe ... St35.4/8,St42,St45,St52,St52.4A53B, A106B, API 5L B,X42,X46,X52,X60, X65STP G38,STP G42,STPT42, ... attentive services3.Reliable partnerOthers:1.Surface Treatment:Transparent oil or black painting anti-corrosion2.Application:Natural gas, petroleum, ...