ISO 8747:2025

Overview

ISO 8747:2025 specifies the characteristics of grooved pins with countersunk head and full‑length diamond grooves. Applicable to steel and stainless‑steel pins with nominal diameters from 2 mm to 20 mm, the standard covers pins with a pilot point (PL) (default) or optional chamfer point (CH). These pins are designed for easy installation and high pull‑out resistance through an elastic fit. General functional principles and assembly requirements for grooved pins are covered by ISO 13669.

Key topics and requirements

• Range and geometry
  • Nominal diameters: 2 mm to 20 mm; dimensions and standard lengths detailed in tabular form.
  • Countersunk head with full‑length diamond grooves; three grooves arranged around the pin.
  • Default pilot point (PL) for closed‑end grooves; chamfer point (CH) opens grooves and is by order.
• Dimensional controls
  • Expanded diameter (d) and pin straightness (t) inspection referenced to ISO 13669.
  • For coated pins, dimensions and tolerances apply prior to coating.
• Materials and surface condition
  • Materials: steel (St) and stainless steels (grades A1, A2, A4, C1, F1); other materials by agreement.
  • Surface finishes and coatings referenced to ISO 4042, ISO 10683, ISO 9717; stainless‑steel selection per ISO 3506‑6.
• Mechanical and inspection requirements
  • Mechanical and physical properties, shear resistance and hardness references are aligned with ISO 13669.
  • Acceptance inspection per ISO 3269; workmanship requirements (free of burrs and defects).
• Labelling and designation
  • Required package marking includes ISO reference, nominal diameter × length, material symbol, point option (CH), finish, lot number, quantity, and manufacturer ID.
  • Standard designation examples provided (e.g., Grooved pin ISO 8747 – 6 × 20 – St).

Applications and who uses this standard

• Applications
  • Permanent or semi‑permanent locking of two or more parts in mechanical assemblies where high pull‑out resistance and easy installation are required (e.g., automotive, machinery, tooling, and general manufacturing).
• Users
  • Fastener manufacturers, product designers, mechanical engineers, quality/inspection labs, procurement and supply chain teams specifying compliant pins, and standards/technical writers preparing specifications.

Related standards

• ISO 13669 - Grooved pins: general requirements (functional principles, hole dimensions, controls)
• ISO 3506‑6 - Stainless steel selection for fasteners
• ISO 4042, ISO 10683, ISO 9717 - Coating and surface treatments
• ISO 3269, ISO 1891‑4 - Acceptance and labelling/quality control
• Related grooved‑pin product standards: ISO 8739–8746, ISO 13670, ISO 13672

Keywords: ISO 8747, grooved pins, countersunk head, full‑length diamond grooves, pilot point, chamfer point, fasteners, pull‑out resistance, expanded diameter, ISO 13669.