... seamless steel Grade J55 Casing and Tubing pipe 1.Grade: J55,K55,N80,L80,P110 2.Thread: STC,BTC,LTC, 3 ... productions capacity. At present ,we have the advanced casing and tubing thread production line ,anti-corrosion insulation production line ,coupling production ... the advanced quality inspection equipments and the high-temperature phosphating process which can assure the thread used many times. In ...