Technical specifications and application of EN ISO 8674 high nuts
The international standard EN ISO 8674 regulates the geometric and operational parameters of high hexagon nuts (style 2) equipped with a metric fine thread. The products are intended for critical assemblies with a nominal thread diameter from 8 mm to 36 mm. According to the classification, products with a nominal thread diameter up to and including 16 mm belong to accuracy class A, while nuts with a diameter over 16 mm belong to class B.
The engineering department of EV Group China recommends taking into account the requirements of ISO 724, ISO 898-2, ISO 965-1, and ISO 4759-1 standards when designing high-load connections to ensure full compatibility of the fasteners.
Technical delivery conditions and quality standards
| Manufacturing material | Steel |
| General requirements | ISO 8992 |
| Thread tolerance class | 6H (ISO 724, 965-1) |
| Property class | D≤16 mm: 8, 12; D≤39 mm: 10 (according to ISO 898-2) |
| Product grades | D≤16 mm: grade A; D>16 mm: grade B (according to ISO 4759-1) |
| Surface quality | Electroplating — ISO 4042; Zinc flake coatings — ISO 10683. Specific requirements for finish are agreed upon with EV Group China when placing an order. |
| Surface condition | Defect control according to ISO 6157-2 |
| Testing methods | In accordance with ISO 3269 protocols |