Overview
EN ISO 13670:2025 (ISO 13670:2025) specifies the characteristics of reverse‑taper grooved pins with one quarter‑length progressive grooves on both sides (closed ends). The standard covers pins in steel and stainless steel, with nominal diameters from 2 mm to 25 mm, and defines their intended functions: enabling relative rotation between assembled parts and locking two or more parts with easy installation and medium pull‑out resistance due to elastic fit behaviour. General functional principles and assembly guidance are referenced to ISO 13669.
Keywords: EN ISO 13670:2025, reverse‑taper grooved pins, grooved pin dimensions, fasteners standard, stainless steel grooved pins.
Key topics and technical requirements
- Scope and geometry
- Reverse‑taper design with progressive grooves occupying one quarter of the pin length at each end (closed grooves).
- Nominal diameter range: 2 mm–25 mm; standard lengths and dimensional tolerances are defined in the document.
- Ends: normally rounded (RN); chamfered (CH) ends allowed on request.
- Dimensions and tolerances
- Detailed dimensional tables and figure references specify nominal diameters, expanded diameter, groove lengths (l/4), and tolerances for different length ranges.
- Control of expanded diameter and pin straightness follows requirements in ISO 13669.
- Materials and surface condition
- Primary materials: steel and stainless steel (various grades, with ISO 3506‑6 for stainless selection).
- Surface treatments and coatings referenced: ISO 4042 (electroplated), ISO 10683 (zinc flake), ISO 9717 (phosphate), and other finishes by agreement.
- Quality and inspection
- Workmanship: pins must be free from burrs and detrimental defects.
- Acceptance and inspection procedures: ISO 3269 and vocabulary/control references such as ISO 1891‑4.
- Labelling and designation
- Package labelling must include reference to ISO 13670, nominal diameter (d), nominal length (l), and options (e.g., CH for chamfered ends).
Applications and users
- Design engineers specifying fasteners for mechanical assemblies requiring:
- controlled relative rotation,
- medium locking force with easy installation.
- Fastener manufacturers and quality teams using the standard to produce and inspect pins to consistent dimensional and material requirements.
- Purchasing and procurement for sourcing standardized grooved pins (clear specification of d, l, material, surface finish).
- Sectors: general engineering, machinery, automotive components, industrial assembly fixtures and any application needing reliable pin locking with elastic fit behaviour.
Related standards
EN ISO 13670:2025 is essential for consistent specification, manufacturing and inspection of reverse‑taper grooved pins used in precision assemblies and mechanical locking applications.
