Name Specification (mm) length standard grades Hot-rolled ribbed steel bars 10-50 HRB335, HRB400 GB1499-1998 6-12 Round 10-50 Q195-255 45 # -80 # ML10, ML20, ML40 40Cr, 20CrMo GB700-88 GB699-88 GB6478-86 GB3077-88 GB13013-91 GB702-86 6-12 Iron bar 16-50 WDT0, WDT4 WJX [BC] 01-2001 6-12 Bearing Steel 12-50 GCr15 GB/T18254-2000 6-12