... rolled or hot dipped Zinc-coated for round,equal,rectangle steel pipe.8) Producing: Seamless,Welded,hot rolled,pre glavanized hot ... ) Standard: GB/T6728, ASTM-A53 10) Using: Structural Tubing,Forniture tube,For water,Gas Severage composition ,100% maxCMnSiSPQ1950.06~0.120 ... .14-0.220.30-0.70.30.050.045 Furniture steel tube/pipe