Overview
EN 14218:2003 specifies the characteristics of hexagon nuts with flange having metric fine pitch thread (based on ISO 10663:1999, modified). The standard covers nominal thread diameters from 8 mm up to and including 20 mm, defines applicable product grades and property classes, and sets dimensional, mechanical and acceptance requirements for these flanged hex nuts used in mechanical assemblies.
Key facts:
- Title: Hexagon nuts with flange - Fine pitch thread (ISO 10663:1999, modified)
- Organization: CEN (European Standard)
- Diameters covered: 8 mm to 20 mm
- Property classes included: 8, 10, 12 and A2‑70
- Modifications to ISO 10663: M10 width‑across‑flats specified as 16 mm (instead of 15 mm); property class 9 deleted; option added for zinc flake coatings per EN ISO 10683
Key topics and requirements
- Dimensions & tolerances: Detailed dimensional tables and figures define hexagon geometry, flange thickness, wrenching heights and corner radii for specified thread sizes. Tolerances reference EN ISO 4759‑1 and ISO thread standards (ISO 261 / ISO 724 / ISO 965‑2).
- Product grades and styles: The standard indicates product grades and style decisions (see normative Table 2) relevant for mechanical properties and testing.
- Mechanical properties: Nuts are covered for property classes 8, 10, 12 and A2‑70 with mechanical requirements referenced to EN ISO 898‑6 (fine pitch nuts) and EN ISO 3506‑2 (stainless steel).
- Surface finishes and coatings: Electroplating referenced to EN ISO 4042; non‑electrolytically applied zinc flake coatings to EN ISO 10683.
- Acceptance & inspection: Acceptance inspection procedures reference EN ISO 3269; limits for surface discontinuities reference EN 493.
- Gauging: Annex A (normative) describes practical gauging methods using plain ring gauges (A and B) and a gauge C for flange thickness to verify dimensions and corner fill.
Applications and users
EN 14218 is used by:
- Fastener manufacturers and formulators of product specifications
- Mechanical design engineers and procurement teams specifying fine‑pitch flanged hex nuts for assemblies
- Quality and inspection personnel performing acceptance testing and gauging
- Suppliers and purchasers who require harmonised European dimensions, tolerances and mechanical class designations
Typical practical uses:
- Mechanical assemblies where a flange provides a bearing surface and fine pitch thread is required for precision adjustment or higher thread engagement
- Applications specifying stainless‑steel A2‑70 nuts or high‑strength property classes (8, 10, 12)
Related standards
Relevant referenced documents for complementary requirements and selection:
Example designation from the standard:
Hexagon nut with flange EN 14218 - M12 x 1,25 - 10.
