Overview
EN ISO 8765:2022 - Fasteners: Hexagon head bolts with fine pitch thread - Product grades A and B - is a CEN-endorsed international standard that defines the characteristics, dimensions and identification requirements for hexagon head bolts (partially threaded) in steel and stainless steel with metric fine pitches. The standard covers thread sizes from M8×1 up to M64×4, and specifies product grades A and B. It replaces EN ISO 8765:2011 and incorporates technical revisions to dimensions, property classes and marking.
Key topics & technical requirements
- Scope and sizes: Metric fine pitch threads M8×1 to M64×4; bolts in steel and stainless steel; product grades A and B.
- Dimensions and tolerances: Detailed dimensional tables and figures (Clause 4 and Annex A) set head geometry, shank and thread lengths, chamfer/end forms and shortest/longest standard lengths.
- Mechanical properties: Property classes and stainless-steel grades referenced; where alternate specifications are needed users can select from ISO 898-1 (carbon/alloy steel) or ISO 3506-1 (stainless steel).
- Marking and labelling: Requirements for marking on the product and labelling on packaging are specified (Clause 6) to support traceability and conformity.
- Referenced quality and test norms: The standard uses and refers to established fastener norms such as ISO 225, ISO 262, ISO 4753, ISO 888, ISO 4759-1, ISO 6157, and coating/acceptance standards (e.g., ISO 4042, ISO 10683, ISO 3269).
- Notable updates (2022 edition): revised dimension tables, addition of M18×2, revised shortest/longest length rules, changes to steel and stainless property class options and expanded marking/labelling specifications.
Applications and who uses it
- Fastener manufacturers use EN ISO 8765:2022 to design, produce and control hexagon head bolts with fine pitch threads to ensure interchangeability and compliance.
- Design and mechanical engineers reference the standard when specifying bolts for machinery, automotive, aerospace subassemblies, and precision equipment where fine-pitch threads are required.
- Purchasing & quality teams rely on the standard for procurement specs, incoming inspection criteria and supplier conformance.
- Testing laboratories & certification bodies use the referenced mechanical and acceptance standards for verification and conformity assessment.
Related standards
EN ISO 8765:2022 is essential for anyone specifying or producing metric hexagon head bolts with fine pitch threads and seeking conformity with current international dimension, marking and quality practices.