Overview
EN ISO 8676:2022 (ISO 8676:2022) is the CEN-adopted international standard that specifies the characteristics of hexagon head screws with fine pitch metric threads (M8×1 to M64×4) in steel and stainless steel. It defines product grades A and B, dimensional requirements, permissible lengths, marking and labelling, and references the mechanical and material property standards to be used when other specifications are required.
Key topics and requirements
- Scope and sizes: Covers fully threaded hexagon head screws with metric fine pitch threads from M8×1 to M64×4 and product grades A and B.
- Dimensions and tolerances: Dimensional tables and figures are provided (Clause 4, Tables 1–5 and Annex A) with head, thread and length details; symbols follow ISO 225.
- Length rules: Rules for the shortest and greatest standard lengths are defined; greatest standard length limited to 200 mm (longer lengths by agreement per ISO 888).
- Materials and properties: Applies to steel and stainless steel screws. When other property classes or stainless steel grades are requested, selection should follow ISO 898-1 (carbon/alloy steel) or ISO 3506-1 (stainless steel).
- Product grades: Grades A and B specify differing dimensional/tolerance levels and permitted dimensions (see tables and Annex A for grade B specifics).
- Marking and labelling: Requirements for product marking and package labelling are included (Clause 6).
- References and conformity: Normative references include ISO 888, ISO 4753, ISO 4759-1 (tolerances for product grades), ISO 6157 (surface discontinuities), and other fastener standards used for inspection and designation.
Practical applications and users
- Manufacturers and suppliers: Use EN ISO 8676:2022 to design, produce and certify hexagon head screws with fine pitch threads that meet European and international expectations.
- Design and mechanical engineers: Reference the standard when specifying fasteners in machinery, automotive components, precision assemblies, instrumentation and other applications that require fine-pitch thread engagement.
- Purchasing and quality assurance: Use dimension tables, length rules and marking requirements for procurement specifications, incoming inspection and acceptance testing.
- Standards and compliance professionals: Apply the standard alongside ISO 898-1 and ISO 3506-1 when defining property classes or stainless steel grades.
Related standards (select)
- ISO 898-1 - Mechanical properties of fasteners (carbon/alloy steel)
- ISO 3506-1 - Mechanical properties of stainless steel fasteners
- ISO 888 - Nominal lengths and thread lengths
- ISO 4753 - Ends of parts with external ISO metric thread
- ISO 4759-1 - Tolerances for product grades A, B and C
Keywords: EN ISO 8676:2022, ISO 8676:2022, hexagon head screws, fine pitch thread, product grades A and B, metric fasteners, dimensions, marking, property classes.
