This standard is equivalent to the International Standard ISO 8675:1999 Hexagon head bolts with metric fine pitch thread - Product grades A and B.
This standard is part of the series standards on Hexagon drive fasteners. The series comprises:
a) Hexagon head bolts: GB/T 27, GB/T 28, GB/T 29.1, GB/T 29.2, GB/T 31.1, GB/T 31.2, GB/T 31.3, GB/T 32.1, GB/T 32.2, GB/T 32.3, GB/T 5780, GB/T 5781, GB/T 5782, GB/T 5783, GB/T 5784, GB/T 5785 and GB/T 5786;
b) Hexagon nuts: GB/T 41, GB/T 56, GB/T 802, GB/T 804, GB/T 805, GB/T 808, GB/T 889.1.GB/T 889.2, GB/T 923, GB/T 6170, GB/T 6171, GB/T 6172.1, GB/T 6172.2, GB/T 6173, GB/T 6174, GB/T 6175, GB/T 6176, GB/T 6178, GB/T 6179, GB/T 6180, GB/T 6181, GB/T 6182, GB/T 6184, GB/T 6185.1, GB/T 6185.2, GB/T 6186, GB/T 9457, GB/T 9458, GB/T 9459 and GB/T 18195;
c) Hexagon bolts with flange: GB/T 5789, GB/T 5790 and GB/T 16674;
d) Hexagon nuts with flange: GB/T 6177.1, GB/T 6177.2, GB/T 6183.1, GB/T 6183.2, GB/T 6187.1 and GB/T 6187.2;
e) Bolted joints for structural bolting: GB/T 1228, GB/T 1229, GB/T 1230, GB/T 3632, GB/T 16939, GB/T 18230.1, GB/T 18230.2, GB/T 18230.3, GB/T 18230.4, GB/T 18230.5, GB/T 18230.6 and GB/T 18230.7;
f) Hexagon head screws, wood screws, tapping screws and assemblies: GB/T 838, GB/T 102, GB/T 5285, GB/T 6563, GB/T 9456, GB/T 15856.4, GB/T 16824.1, GB/T 16824.2, GB/T 9074.11, GB/T 9074.12, GB/T 9074.13, GB/T 9074.14, GB/T 9074.15, GB/T 9074.16, GB/T 9074.17, GB/T 9074.20, GB/T 9074.21, GB/T 9074.22 and GB/T 9074.23.
ISO 8675 does not specify technical requirements for packaging, which are specified in this standard (Table 3).
Simplified designation is not specified in ISO 8675, while this standard provides a simplified example of designation (5.2) in accordance with GB/T 1237.
This standard does not adopt the catalog attached to ISO 8675, which the contents are listed in foreword.
This standard is the revision of GB/T 6173-1986, the main changes in this standard are as follows:
a) Classified according to the degree of thread preference: Table 1 Preferred threads (equivalent to Tables 1 and 2 of the old standard); Table 2 Non-preferred threads (equivalent to Table 3 of the old standard);
b) Three non-preferred thread sizes such as M10×1.25, M12×1.25 and M20×2 are added (Table 2);
c) Reference to GB/T 16938 general requirements is added (Table 3);
d) The non-ferrous metal nuts, with reference to GB/T 3098.10 by the supply and demand sides agreed to choose the performance level is added (Table 3);
e) A non-electrolytic coating is added.
This standard replaces GB/T 6173-1986 from the implementation date hereof.
This standard was proposed by the State Bureau of Machine Building Industry.
This standard is under the jurisdiction of National Technical Committee on Fasteners of Standardization Administration of China.
The Secretariat of the National Technical Committee on Fasteners of Standardization Administration of China is in charge of the explanation of this standard.
ISO Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical (IEC) all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives Part 3.
Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75% approval by the member bodies voting.
International Standard ISO 8675 was prepared by Technical Committee ISO/TC 2, Fasteners.
This second edition cancels and replaces the first (ISO 8675:1988), has been technically revised.
ISO Introduction
This International Standard is part of the complete ISO product standard series on External hexagon drive fasteners. The series comprises:
a) Hexagon head bolts (ISO 4014 to ISO 4016 and ISO 8765);
b) Hexagon head screws (ISO 4017, ISO 4018 and ISO 8676);
c) Hexagon nuts (ISO 4032 to ISO 4036, ISO 8673 to ISO 8675):
d) Hexagon bolts with flange (ISO 4162 and ISO 15071);
e) Hexagon nuts with flange (ISO 4161 and ISO 10663):
f) Structural bolts and nuts (ISO 4775, ISO 7411 to ISO 7414 and ISO 7417).
Hexagon thin nuts (chamfered) with fine pitch thread
1 Scope
This standard specifies hexagon thin nuts with thread specifications M8×1 to M64×4, fine pitch thread, performance grades 04, 05, A2-025, A4-025, A2-035, A4-035, CU2, CU3 and AL4, product grades A and B chamfer. Class A is used for D ≤ 16 mm; Class B is used for D > 16mm.
If, in special cases, specifications other than those listed in this standard are required, they should be selected from existing standards, for example GB/T 196, GB/T 3098.4, GB/T 3098.15 and GB/T 3103.1.
Coarse thread bolts according to GB/T 6172.1 should be first choice.
2 Normative references
The following standards contain provisions which, through reference in this standard, constitute provisions of this standard. At the time of publication, all editions listed were valid. All normative references are subject to revision, and parties to agreements based on this standard are encouraged to investigate the possibility of applying the latest editions of the normative standards indicated below.
GB/T 90-1985 Acceptance inspection,marking and packaging of fasteners (eqv ISO 3269:1984)
GB/T 196-1981 General purpose screw threads - Basic dimensions for diameter from 1 to 600mm
GB/T 197-1981 General purpose screw threads - Tolerances and fits for diameter from 1 to 355mm
GB/T 1237-2000 Designation system for fasteners ( eqv ISO 8991:1986)
GB/T 3098.4-2000 Mechanical properties of fasteners - Nuts - Fine pitch thread (idt ISO 3506-1:1997)
GB/T 3098.10-1993 Mechanical properties of fasteners Bolts, scrows, studs and nuts made of non-ferrous ( eqv ISO 8839:1986)
GB/T 3098.15-2000 Mechanical properties of fasteners - Nuts made of stainless-steel (idt ISO 3506-2:1997)
GB/T 3103.1-1982
(confirmed in 1988) Tolerances for fasteners - Bolts,screws and nuts (eqv ISO 4759-1:1978)
GB/T 5267-1985 Electroplated coatings on threaded fasteners
GB/T 5276-1985 Fasteners; Bolts, screws,studs and nuts; Symbols and designations of dimensions ( eqv ISO 225:1983)
GB/T 5779.2-2000 Fasteners - Surface discontinuities-Nuts (idt ISO 6157-2:1995)
GB/T 6172.1-2000 Hexagon thin nuts (chamfered) (eqv ISO 4035:1999)
GB/T 16938-1997 Fasteners - General requirements for blots,screws,studs and nuts (idt ISO 8992:1986)
ISO 10683:2000 Fasteners - Non-electrolytically applied zinc flake coatings
3 Dimensions
Note: designations and symbols of dimensions shall meet GB/T 5276.
1) β＝15° to 30°;
1) θ＝90° to 120°.
Figure 1
Table 1 Preferred threads
Table 2 Non-preferred threads
4 Technical conditions and normative references
Table 3 Specifications and reference standards
Material Steel Stainless steel Non-ferrous metal
General requirements GB/T 16938
Thread Tolerances 6H
Standard GB/T 196 and GB/T 197
Mechanical properties Grade D ≤ M39: 04, 05
D > M39: as agreed D ≤ M24: A2-035, A4-035
M24 < D ≤ M39: A2-025, A4-025
D > M39: as agreed
CU2, CU3, AL4
Standard D≤M39 : GB/T 3098.4
D > M39: as agreed
D ≤ M39 : GB/T 3098.15
D>M39: as agreed Materials specified in GB/T 3098.10.
Tolerances Product grades D≤16 mm:A; D>16 mm:B
Standard GB/T 3103.1
Surface defect GB/T 5779.2
Finish Plain Simple treatment Simple treatment
Requirements for electroplating are covered in GB/T 5267.
Requirements for non-electrolytically applied zinc flake coatings are covered in ISO 10683.
If different electroplating requirements are desired or if requirements are needed for other finishes, they shall be agreed between customer and supplier.
Acceptance and packaging
GB/T 90
Foreword I
ISO Foreword III
ISO Introduction IV
1 Scope
2 Normative references
3 Dimensions
4 Technical conditions and normative references
5 Designation
