... Roller Extrusion equipment line. 3.CE,ISO Cold Formed Rectangular Steel Tube 1. STANDARD:GB/T3094-2000, GB/T6728-2002, ASTM ... Q195, Q215, Q235, Q275, Q345, 20#, 45#, Stainless steel, Seamless steel, Alloy steel.3. SURFACE:Bared, Galvanized, Oiled, Color Paint, 3PE; ... in this area.We engaged in research square and rectangular steel tube at the beginning of company established, now our technology ...