GB/T 3098.2-2015 in English

《GB/T 3098.2-2015紧固件机械性能 螺母》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。
GB/T3098的本部分规定了在环境温度为10 ℃~35 ℃条件下进行试验时,由碳钢或合金钢制造
的粗牙螺纹和细牙螺纹的螺母机械和物理性能。
在该环境温度范围内,符合本部分技术要求的螺母,在较高或较低温度下,有可能达不到规定的机
械和物理性能。
注1:按本部分生产的螺母适用的使用温度为-50 ℃~+150 ℃。当使用温度超过-50 ℃~+150 ℃,甚至高达
+300 ℃时,使用者应当咨询有经验的紧固件材料专家。
注2:对低温和高温用钢的选择与应用实例,可参考 EN10269、ASTM F2281和 ASTM A320/A320M。
本部分适用的螺母:
a) 由碳钢或合金钢制造的;
b) 粗牙螺纹规格:M5≤D≤M39,和细牙螺纹规格:M8×1≤D≤M39×3;
c) 符合 GB/T192规定的普通螺纹;
d) 符合 GB/T193和 GB/T9144规定的直径与螺距组合;
e) 规定性能等级和保证载荷;
f) 规定了薄螺母、标准螺母和高螺母三种螺母型式;
g) 螺母高度mmin≥ 0.45D;
h) 外径或对边宽度smin≥1.45D(参见附录 A);
i) 能与规定性能等级(GB/T3098.1)的螺栓、螺钉和螺柱搭配使用。
对热浸镀锌螺母表面处理的技术要求,见 GB/T5267.3。
本部分未规定以下性能要求:
―――有效力矩型锁紧性能(见 GB/T3098.9);
―――扭矩-夹紧力性能(试验方法见 GB/T16823.3);
―――可焊接性;
―――耐腐蚀性。

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