Scope And Referenced Standards For Hexagon Head Bolts in China

Understanding the relevant standards for hexagon head bolts is of great guiding significance for their proper selection. A complete national standard system for hexagon head bolts has been established in China. Below is a detailed introduction to the standards for your reference.

1. Scope of Hexagon Head Bolts

National Standard GB/T 5785‑2000 specifies fine‑thread hexagon head bolts with thread sizes from M8×1 to M64×4. Their property classes include 5.6, 8.8, 10.9, A2‑70, A4‑70, A2‑50, A4‑50, CU2, CU3 and AL4, with product grades A and B. Grade A applies to bolts where d = 8–24 mm and L ≤ 10d or L ≤ 150 mm (whichever is smaller). Grade B applies to bolts where d ＞ 24 mm or L ＞ 10d or L ＞ 150 mm (whichever is smaller). If additional technical requirements are needed, they may be selected from current valid standards (such as GB/T 196, GB/T 3106, GB/T 3098.1, GB/T 3098.6 and GB/T 3103.1). Preference shall be given to coarse‑thread hexagon head bolts specified in GB/T 5782.

2. Referenced Standards

The production of hexagon head bolts shall comply with the following standards to ensure product quality and compliance:

GB/T 2‑1985, Fasteners - Ends of externally threaded parts

GB/T 90‑1985, Fasteners - Acceptance inspection, marking and packaging

GB/T 196‑1981, General purpose screw threads - Basic dimensions (diameters 1–600 mm)

GB/T 197‑1981, General purpose screw threads - Tolerances and fits (diameters 1–355 mm)

GB/T 1237‑2000, Fasteners - Marking system (eqv ISO 8991:1986)

GB/T 3098.1‑2000, Mechanical properties of fasteners - Bolts, screws and studs (idt ISO 898‑1:1999)

GB/T 3098.6‑2000, Mechanical properties of fasteners - Stainless steel bolts, screws and studs

GB/T 3098.10‑1993, Mechanical properties of fasteners - Bolts, screws, studs and nuts made of non‑ferrous metals

GB/T 3103.1‑1982, Tolerances for fasteners - Bolts, screws and nuts

GB/T 3106‑1982, Nominal lengths of bolts, screws and studs, and thread lengths for ordinary bolts

GB/T 5267‑1985, Electroplated coatings on threaded fasteners

GB/T 5276‑1985, Fasteners - Bolts, screws, studs and nuts - Symbols and designations of dimensions

GB/T 5779.1‑2000, Surface discontinuities of fasteners - Bolts, screws and studs - General requirements

GB/T 5779.3‑2000, Surface discontinuities of fasteners - Bolts, screws and studs - Special requirements

GB/T 5782‑2000, Hexagon head bolts

GB/T 5786‑2000, Hexagon head bolts - Fine pitch thread - Full thread

GB/T 16938‑1997, Fasteners - Bolts, screws, studs and nuts - General technical requirements

ISO 10683:2000, Fasteners - Non‑electrolytically applied zinc flake coatings

The provisions of the standards cited herein constitute the provisions of this document. All standards are subject to revision. Users of this document are encouraged to investigate the possibility of applying the latest editions of the standards listed above.

The above is a detailed introduction to the standards for hexagon head bolts. Familiarity with these standards helps users better understand hexagon head bolts, select suitable bolts, and guarantee the safety and quality of connections.