1 Scope
This part of GB/T 3098 specifies mechanical and physical properties of nuts with coarse thread and fine pitch thread made of carbon steel and alloy steel when tested at an ambient temperature range of 10℃ to 35℃.
Nuts conforming to the requirements of this part are evaluated at that ambient temperature range. It is possible that they do not retain the specified mechanical and physical properties at elevated and/or lower temperatures.
Note 1: Nuts conforming to the requirements of this part of ISO 898 have been used in applications ranging from –50 ℃ to +150 ℃. It is the responsibility of users to consult an experienced fastener materials expert for temperatures outside the range of –50℃ to +150℃ and up to a maximum temperature of +300°C to determine appropriate choices for a given application.
Note 2: Information for the selection and application of steels for use at lower and elevated temperatures is given for instance in EN 10269, ASTM F2281 and in ASTM A320/A320M.
This part is applicable to nuts:
a) made of carbon steel or alloy steel;
b) with coarse thread M5 ≤ D ≤ M39, and fine pitch thread M8×1 ≤ D ≤ M39×3;
c) with triangular metric thread according to GB/T 192;
d) with diameter/pitch combinations according to GB/T 193 and GB/T 9144;
e) with specified property classes, including proof load;
f) with different nut styles: thin nuts, regular nuts and high nuts;
g) with minimum height m ≥ 0.45D;
h) with a minimum outside diameter or width across flats s ≥ 1.45D (see Annex A);
i) able to mate with bolts, screws and studs with property classes according to GB/T 3098.1.
Foreword II
1 Scope
2 Normative References
3 Symbols
4 Designation Systems
5 Design of Bolt and Nut Assemblies
6 Materials
7 Mechanical Properties
8 Inspection
9 Test Methods
10 Marking
Annex A (Informative) Design Principles of Nuts
Annex B (informative) Thread Dimensions for the Test Mandrel