... . 3.Standard : GB , API CommodityOil casing pipe/tubePlace of originTianjin , China(Mainland)StandardAPI,GBMaterialJ55,K55,N80,L80,N80,P11,P91,P110 ... casing, conveying gas and oil,chemical industry,etc NoteWe are Tianjin Hong-Peng High-Pressure Alloy Pipe Sales Co.,ltd,which ... is a leading expoter and manufacturer in China. Our company insist on a "first-class management ,first-class ...