GB/T 16823.2-1997 in English

《GB/T 16823.2-1997螺纹紧固件紧固通则》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。
本标准规定了拧紧螺栓-螺母螺纹连接副的术语、基本要求、主要关系式以及典型的拧紧方法。本标准也适用于螺栓-螺母以外的螺纹连接副。本标准不适用于带弹簧垫圈、弹性垫圈的螺纹连接副和使用自攻螺钉、木螺钉，以及使用有效力矩型1)螺纹紧固件的连接副。

1 Scope

This standard specifies general matters relating to significance of tightening by combination of bolt and nut, basis of tightening and representative control method.

Further, this standard is applicable to bolted joint other than the bolt and nut.

However, it is not applicable to bolted joint with spring washer or elastic washer, or bolted joint where self-tapping screws, wood screws, or prevailing torque type1) threaded fasteners are used.

2 Normative references

The following standards contain provisions which, through reference in this text, constitute provisions of this standard. At the time of publication, all the editions listed are valid. All standards are subject to revision, and all parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below.

GB 3098.1-82 Mechanical properties of fasteners - Bolts, screws and studs
GB 3104-82 Fasteners - Widths across flats of hexagon products
GB 5277-85 Fasteners - Clearance holes for bolts and screws
GB 9145-88 General purpose screw threads - Limits of sizes for commercial bolt and nut threads - Medium quality
GB/T 16823.1-1997 Stress area and bearing area for threaded fasteners;
GB/T 16823.3-1997 Method of tightening test for threaded fasteners.

3 Terms and symbols

3.1 Terms

For the purpose of this standard, main terms and their definitions shall be in accordance with Table 1.

Foreword i
1 Scope
2 Normative references
3 Terms and symbols
4 Significance of tightening
5 Base of tightening
6 Tightening control of screw threads
Annex A (Normative) Calculation values of torque coefficient to coefficient of friction between threads and coefficient of friction between bearing surfaces
Annex B (Normative) Calculation values of yield clamping force and yield tightening torque to coefficient of friction between threads and coefficient of friction between bearing surfaces