GB/T 32.3-2020Hexagon bolts with wire holes on head—Fine pitch thread (English PDF)

Foreword

GB/T 32, "Hexagon bolts with wire holes on head", is divided into 3 parts:

-- GB/T 32.1, Hexagon bolts with wire holes on head;

-- GB/T 32.2, Hexagon bolts with wire holes on head - Reduced shank - Product grade B;

-- GB/T 32.3, Hexagon bolts with wire holes on head - Fine pitch thread.

This Part is Part 3 of GB/T 32.

This Part was drafted in accordance with the rules given in GB/T 1.1-2009.

This Part replaces GB/T 32.3-1988, "Hexagon bolts with wire holes on head - Fine pitch thread - Product grade A and B". Compared with GB/T 32.3-1988, the major technical changes are as follows:

-- Divide the types and dimensions into two tables according to the preferred specifications and the non-preferred specifications (see Table 1 and Table 2; Chapter 3 of version 1988);

-- Add a table of technical conditions and reference standards (see Table 3).

1 Scope

This part of GB/T 32 specifies the types and dimensions, technical conditions and reference standards, and designation of hexagon bolts with wire holes on head of fine pitch thread.

This Part is applicable to hexagon bolts with wire holes on head, of nominal thread diameter of d = 8 mm ~ 48 mm, fine pitch thread, property grades of 5.6, 8.8, 10.9, A2-70, A4-70, A2-50, A4-50, CU2, CU3 and AL4, products grades of A and B.

The bolts which are specified in this Part are made with wire holes in the head of the products that comply with GB/T 5785.

2 Normative references

The following documents are indispensable for the application of this document.

For dated references, only the dated version applies to this document. For undated references, the latest edition (including all amendments) applies to this document.

GB/T 90.1, Fasteners - Acceptance inspection

GB/T 90.2, Fasteners - Marking and packaging

GB/T 193, General purpose metric screw threads - General plan

GB/T 1237, Designation system for fasteners

GB/T 3098.1, Mechanical properties of fasteners - Bolts, screws and studs

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

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

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

GB/T 5267.1, Fasteners - Electroplated coatings

GB/T 5267.2, Fasteners - Non-electrolytically applied zinc flake coatings

GB/T 5267.4, Passivation of corrosion-resistant stainless-steel fasteners

GB/T 5276, Fasteners - Bolts, screws, studs and nuts - Symbols and descriptions of dimensions

GB/T 5278, Fasteners - Split pin holes and wire holes

GB/T 5779.1, Fasteners - Surface discontinuities - Bolts, screws and studs for general requirements

GB/T 5785, Hexagon head bolts - Fine pitch thread

GB/T 9145, General purpose metric screw threads - Limits of sizes for the screw threads of medium quality and preferable plan

GB/T 16938, Fasteners - General requirements for bolts, screws, studs and nuts

3 Types and dimensions

The types of bolts are shown in Figure 1; the preferred specifications and dimensions are shown in Table 1; the non-preferred specifications and dimensions are shown in Table 2; the remaining types and dimensions are in accordance with GB/T 5785. Symbols and descriptions of dimensions shall comply with GB/T 5276. […]