Overview
ISO 13670:2025 specifies the characteristics of reverse‑taper grooved pins with one quarter‑length progressive grooves on both sides (closed ends) manufactured in steel and stainless steel, for nominal diameters 2 mm to 25 mm. These grooved pins are intended to provide easy, symmetrical installation, medium pull‑out resistance through elastic fit behaviour, and functions such as relative rotation of assembled parts or locking two or more components. General principles and assembly guidance are given by ISO 13669.
Key topics and requirements
- Geometry and dimensions
- Grooves occupy one quarter of the pin length at each end; groove start must remain closed (not enter rounded/chamfered ends).
- Nominal diameters covered: 2 mm to 25 mm; standard lengths and expanded diameters defined in tables.
- Groove arrangement: six grooves with 120° spacing (±20°); groove angle ~70° (reference).
- Groove length tolerances and maximum distances from ends (l max) are specified according to pin length ranges.
- Options for rounded (RN) or chamfered (CH) ends.
- Mechanical and quality requirements
- Material options: steel (symbol St) and specified stainless grades (A1, A2, A4, C1, F1), with mechanical properties referenced to ISO 3506-6 and ISO 13669.
- Control of expanded diameter and pin straightness per ISO 13669.
- Workmanship: pins must be free of burrs and detrimental defects.
- Acceptance inspection procedures per ISO 3269.
- Surface finishes and coatings
- As‑processed for steel and clean & bright for stainless steel by default.
- Coating options referenced: electroplated (ISO 4042), phosphate (ISO 9717), zinc‑flake (ISO 10683); passivation options (e.g., ISO 16048).
- Labelling & designation
- Packaging must include ISO reference, nominal d × l, end option (CH/RN), material symbol/grade, surface condition, manufacturer ID, lot number and quantity.
- Examples of standard designation formats are provided.
Applications and users
- Typical uses: mechanical assemblies where controlled relative rotation or positive locking with medium pull‑out resistance is required - e.g., general machinery, fixtures, jigs, light automotive and appliance assemblies.
- Primary users:
- Fastener manufacturers and suppliers specifying production tolerances and finishes
- Design and mechanical engineers selecting pins for assembly functions
- Quality and inspection teams applying acceptance criteria and labelling
- Purchasing/specification writers creating procurement documents
Related standards
Keywords: ISO 13670, reverse‑taper grooved pins, grooved pins, fasteners, steel pins, stainless steel pins, pin dimensions, pull‑out resistance, grooved pin standards.
Open preview (PDF)Fasteners — Reverse-taper grooved pins — One quarter-length progressive grooves on both sides