Rebar main purposes: widely used in housing, bridges, roads and other civil works construction. Rebar its trademark brand by the HRB and constitute the minimum value of the yield point. H, R, B, respectively, for the hot-rolled (Hotrolled), ribbed (Ribbed), steel (Bars) first three words in English letters. Hot-rolled ribbed bar is divided into HRB335 (old No. 20MnSi), HRB400 (old No. 20MnSiV, 20MnSiNb, 20Mnti), HRB500 three grades