... 20#, 45#, Stainless steel, Seamless steel, Alloy steel.3. SURFACE:Bared, Galvanized, Oiled, Color Paint, 3PE; ... aviation, expressway, overpass, road fence, traffic signs.(3).Construction engineering: steel structure construction, sports venue, three ... GradeWall thickness/t4mm≤t≤10mm ±8%t4mm≤t≤10mm ±8%t10mm≤t≤22mm ±6%t10mm≤t≤22mm ±6% ... .5-2.5)t6mm≤t≤10mm(2-3)tT>10mm(2.5-3.5)tConcave and convex degree ...