This standard is basically consistent with the international standard ISO888-1976 "Bolts, screws and studs - Nominal length and thread length of ordinary bolts". This standard specifies the nominal lengths of bolts, screws and studs, as well as the thread lengths of common bolts, and is applicable to both standard and non-standard fasteners.
GB/T 3106-1982 history
2016GB/T 3106-2016 Fasteners.Bolts, screws and studs.Nominal lengths and thread lengths
1982GB/T 3106-1982 Bolts,screws and studs--Nominal lengths and thread lengths for general purpose bolts