... Roller Extrusion equipment line. 3.Certification:CE, ASTM Carbon Steel Pipes 1. STANDARD:GB/T3094-2000, GB/T6728 ... #, 45#, Stainless steel, Seamless steel, Alloy steel.3. SURFACE:Bared, Galvanized, Oiled, Color Paint, 3PE; Or Other Anti-corrosive Treatment ... overpass, road fence, traffic signs.(3).Construction engineering: steel structure construction, sports venue, three-dimensional garage, exhibition ...