... Advanced Roller Extrusion equipment line. 3.CE,ISO Cold Formed Rectangular Steel Tube 1. STANDARD:GB/T3094-2000, GB/T6728-2002, ASTM ... , container, tricycle, tower crane.6. SPECIFICATION: SQUARE TUBE(MM) THICKNESS (MM)SQUARE TUBE (MM)THICKNESS(MM)20*301.5-3.2590 ... experience in this area.We engaged in research square and rectangular steel tube at the beginning of company established, now our technology ...