GB/T 70.1-2008 in English

《GB/T 70.1-2008内六角圆柱头螺钉》由TC85（全国紧固件标准化技术委员会）归口，主管部门为中国机械工业联合会。
本部分是国家标准“内六角螺钉”产品（含量规）系列标准之一。本部分是ＧＢ／Ｔ７０的第１部分。 本部分代替ＧＢ／Ｔ７０．１―２０００《内六角圆柱头螺钉》。 本部分规定了螺纹规格为Ｍ１．６～Ｍ６４，性能等级为８．８、１０．９、１２．９、Ａ２-５０、Ａ２-７０、Ａ３-５０、Ａ３-７０、Ａ４-５０、Ａ４-７０、Ａ５-５０、Ａ５-７０、ＣＵ２和ＣＵ３，产品等级为Ａ级的内六角圆柱头螺钉。 本部分与ＧＢ／Ｔ７０．１―２０００相比主要变化如下：
―――增加引用标准ＧＢ／Ｔ５２６７．２《紧固件　非电解锌片涂层》和ＧＢ／Ｔ７０．５《内六角量规》（第２章）；
―――增加性能等级：d≤２４ｍｍ：Ａ３-７０和Ａ５-７０；２４ｍｍ＜d≤３９ｍｍ：Ａ３-５０和Ａ５-５０（见表２）；
―――取消附录Ａ；
―――原附录Ｂ“内六角圆柱头螺钉的质量”改为附录Ａ。

1 Scope

This part specifies the characteristics (8.8, 10.9, 12.9, A2-50, A2-70, A3-50, A3-70, A4-50, A4-70, A5-50, A5-70, CU 2 and CU 3) of hexagon socket head cap screws with coarse pitch thread from M 1.6 up to and including M64 and product grade A.
For approximate masses of screws see Appendix A.
If, in special cases, technical requirements other than those listed in this standard are required, they should be selected from existing standards, such as GB/T 196, GB/T 3106, GB/T 3098.1, GB/T 3098.6, GB/T 3098.10 and GB/T 3103.1.

2 Normative References

The following normative documents contain provisions which, through reference in this Part, constitute provisions of this part. For dated reference, subsequent amendments to, or revisions of, any of these publications do not apply. However, all parties coming to an agreement according to this part are encouraged to study whether the latest editions of these documents are applicable. For undated references, the latest edition of the normative document is applicable to this part.
GB/T 2 Fasteners-Ends of Parts with External Thread GB/T 2-2001,idt ISO 4753: 1999)
GB/T 70.5 Gauging of Hexagon Sockets (GB/T 70.5-2008,ISO 23429:2004,IDT)
GB/T 90.1 Fasteners-Acceptance Inspection (GB/T 90.1-2002,idt ISO 3269: 2000)
GB/T 90.2 Fasteners-Marking and Packaging
GB/T 196 General Purpose Metric Screw Threads-Basic Dimensions (GB/T 196-2003,ISO 724: 1993,ISO General Purpose Metric Screw Threads-Basic Dimensions, MOD)
GB/T 197 General Purpose Metric Screw Threads-Tolerances (GB/T 197-2003,ISO 965-1:1998,ISO General Purpose Metric Screw Threads-Tolerances-Part 1:Principles and Basic Data, MOD)
GB/T 1237 Designation System for Fasteners (GB/T 1237-2000,eqv ISO 8991:1986)
GB/T 3098.1 Mechanical Properties of Fasteners-Bolts, Screws and Studs (GB/T 3098.1-2000, idt ISO 898-1:1999)
GB/T 3098.6 Mechanical Properties of Corrosion-Resistant Stainless-Steel Fasteners-Part 1: Bolts, Screws and Studs (GB/T 3098.6-2000, idt ISO 3506-1:1997)
GB/T 3098.10 Mechanical Properties of Fasteners Bolts, Screws, Studs and Nuts Made of Non-Ferrous Metals (GB/T 3098.10-1993, eqv ISO 8869:1986)
GB/T 3103.1 Tolerances for Fasteners-Bolts, Screws, Studs and Nuts (GB/T 3103.1-2002, ISO 4759-1:2000, IDT)
GB/T 3106 Bolts, Screws and Studs; Nominal Lengths and Thread Lengths for General Purpose Bolts [GB/T 3106-1982(affirmed in 1988), eqv ISO 888:1976]
GB/T 5267.1 Fasteners-Electroplated Coatings (GB/T 5267.1-2002, ISO 4042:1999,IDT)
GB/T 5267.2 Fasteners-Non-Electrolytically Applied Zinc Flake Coatings (GB/T 5267.2-2002,ISO 10683:2000,IDT)
GB/T 5276 Fasteners; Bolts, Screws, Studs and Nuts; Symbols and Designations of Dimensions (GB/T 5276-1985, eqv IS0 225:1983)
GB/T 5779.1 Fasteners-Surface Discontinuities-Bolts, Screws and Studs for General Requirements (GB/T 5779.1-2000, idt ISO 6157-1:1988)
GB/T 5779.3 Fasteners-Surface Discontinuities-Bolts, Screws and Studs for Special Requirements (GB/T 5779.3-2000, idt ISO 6157-3:1988)
GB/T 16938 Fasteners-General Requirements for Blots, Screws, Studs and Nuts (GB/T 16938-2008, ISO 8839: 2005, IDT)

3 Dimension

See Figure and Table 1.
Symbol and designations of dimensions shall meet the requirements in GB/T 5276.

Contents
1 Scope
2 Normative References
3 Dimension
4 Technical Conditions and Normative References
5 Designation
Appendix A