Overview
EN ISO 4016:2022 - Fasteners: Hexagon head bolts, product grade C specifies the characteristics of steel hexagon‑head bolts with metric coarse pitch threads M5 to M64 in product grade C. The standard covers dimensional data, requirements, marking and labelling and references related ISO documents for mechanical properties, tolerances and coatings. EN ISO 4016:2022 is the European adoption of ISO 4016:2022 and supersedes the 2011 edition.
Key topics and technical requirements
- Scope: Steel hexagon head bolts, partially threaded, metric coarse pitch M5–M64, product grade C.
- Dimensions: Detailed dimensional requirements are given (see Clause 4) with figures and tables providing head, shank and thread geometry and standard length ranges.
- Tolerances & product grades: Tolerances and product‑grade definitions are linked to ISO 4759-1 and related fastener tolerance standards. Property classes (mechanical strength) can be selected from ISO 898‑1 when other specifications are requested.
- Marking and labelling: Clause 6 specifies marking on the product and labelling on packaging (added/updated in this edition).
- Normative references: The standard references key ISO documents used for design, inspection and finish (examples include ISO 225, ISO 888, ISO 965‑1, ISO 3269, ISO 4042, ISO 4753, ISO 4759‑1, ISO 6157‑1, ISO 8991 / 8992, ISO 10683, ISO 10684).
- Edition changes: Technical revisions in 2022 include added permissible head shapes and underhead details, restructured dimension tables, addition of M7, updates to M5 dimensional tolerance for improved bearing area, clarified rules for shortest/longest standard lengths and explicit marking/labelling rules.
Applications and users
EN ISO 4016:2022 is used by:
- Fastener manufacturers and heat‑treaters for product design, production and quality control.
- Design and mechanical engineers specifying bolts for machinery, automotive, construction and industrial equipment.
- Procurement teams and distributors ensuring interchangeability and correct product grade selection.
- Inspection and quality assurance personnel using standardized dimensions, tolerances and marking requirements for acceptance testing.
Practical benefits include consistent bolt interchangeability, clearer procurement specifications, traceable marking/labeling and alignment with mechanical property standards (ISO 898‑1) and coating standards (ISO 4042, ISO 10683, ISO 10684).
Related standards
Keywords: EN ISO 4016, ISO 4016:2022, hexagon head bolts, product grade C, M5–M64, fasteners standard, bolt dimensions, marking and labelling.