1)Seamless Steel Tubes for Petroleum Cracking Standard：GB9948---------Chinese National Standard Application： It is used for the seamless steel tubes for furnace,heat exchangers and piping in petroleum factories Main Steel Tube Grade: 10,20,1 2C rMo ,15C rMo,1C r2Mo,1C r5Mo,1Crl9Ni9,1Crl9NillNb etc. Other grade can also be provided after consulting with costomers. 2)Line Pipe Standard：API SPEC 5L Application： It is used for conveying gas, water, and petroleum of both the oil and natural gas industries.