Each fastener product will generally involve the following criteria.
1. Dimensional standards for fastener products.
Specify the basic dimensions of the product, for products with threads, you need to include the basic dimensions of the threads, such as the thread end, shoulder pitch, ejector groove and chamfer, the end size of the external thread parts, etc.
2. Standards for the technical conditions of fastener products, including standards for the following.
a) Criteria for fastener product tolerances: Specify dimensional and dimensional tolerances of fasteners.
b) Criteria for mechanical properties of fastener products: Specify the method of marking the mechanical properties of fasteners, which in some cases is changed to material properties or working properties of the product.
c) Standards for surface defects in fastener products: specify the type of surface defects and specific requirements for fasteners.
d) Surface treatment standards for fastener products: specify the type of surface treatment and specific requirements for fasteners.
(e) Standards for testing fastener products: Specify the performance tests mentioned above.
3. Fastener product acceptance inspection, marking and packaging standards: Specify the product factory acceptance inspection of the level of qualified quality of the project and sampling program, as well as product marking methods and packaging requirements.
4. Standards for fastener product marking methods: Specify complete product marking methods and simplified marking methods.
5. Standards for other aspects of fasteners: standards for fastener terminology, standards for fastener product weights, etc.
