Overview
EN ISO 8739:2025 - Fasteners - Parallel grooved pins, with pilot point - Full-length diamond grooves (ISO 8739:2025) specifies the characteristics of parallel grooved pins with a pilot point and full‑length diamond grooves (closed at the insertion side). The standard covers pins manufactured in steel and stainless steel, with nominal diameters from 1 mm to 25 mm, and defines functional intent: easy installation (pilot point) and high pull‑out resistance (elastic fit of the grooved pin). General principles for grooved pins and assembly are given in ISO 13669.
Key topics and technical requirements
- Pin geometry and dimensions: nominal diameters 1–25 mm, standard length ranges, groove geometry (full‑length diamond grooves), end options (rounded or chamfered) and pilot point design.
- Expanded diameter and straightness control: requirements for expanded diameter (d) and pin straightness (t) are specified and referenced to ISO 13669.
- Materials and grades: permitted materials include steel and several stainless‑steel grades (A2, A4, C1, F1). Other materials (hardened steels, brass, aluminium) are allowed by agreement between purchaser and supplier.
- Mechanical and physical properties: mechanical strength, shear resistance and hardness follow the requirements or references in ISO 13669 and related product standards.
- Surface finishes and coatings: coatings and treatments referenced include ISO 4042 (electroplated), ISO 9717 (phosphate), ISO 10683 (zinc flake) and passivation/clean‑bright options. Dimensions and tolerances apply before coating.
- Workmanship and inspection: pins must be free from burrs and harmful defects; acceptance inspection follows ISO 3269.
- Labelling and designation: packaging and labelling requirements are specified to support traceability and procurement.
Applications and users
EN ISO 8739:2025 is used where reliable, repeatable mechanical locking between parts is required with easy insertion and strong pull‑out resistance. Typical users include:
- Fastener manufacturers and suppliers specifying production tolerances and materials
- Design and mechanical engineers selecting grooved pins for assemblies
- Quality and inspection teams applying acceptance criteria
- Procurement and standards officers ensuring compliance in supply chains
Common application areas include machinery assembly, automotive subassemblies, precision equipment and general industrial engineering where dowel/locking pins are required.
Related standards
- ISO 13669 - Fasteners - Grooved pins - General requirements (functional principles, assembly)
- ISO 3269 - Fasteners - Acceptance inspection
- ISO 3506‑6 - Stainless‑steel fasteners (selection rules)
- ISO 4042 - Electroplated coating systems
- ISO 9717 - Phosphate conversion coatings
- ISO 10683 - Zinc flake coatings
For specification or procurement, reference EN ISO 8739:2025 together with ISO 13669 to ensure correct dimensions, material selection and inspection criteria for parallel grooved pins.
