Alloy Pipe,Pipe for chemical fertilizer facility ,Marine Pipe,Casing Pipe,Drill Pipe,Oil Pipe,Structure Pipe ,Pipe of Pipelines Code NO.VarietyNormal Steel GradeStandard NO.1Structure pipe10, ... ,20MnG,25MnG,15Cr1MoVGGB53104Low and Medium Pressure Boiler Tube10,20GB30875High pressure Pipe for Fertilizer Equipment10,20,16Mn,15CrMoGB64796Petroleum Cracking Tube10,20,12CrMo,15CrMoGB99487Tube ...