Overview
ISO 13337:2009 specifies the characteristics of slotted, spring-type straight pins (also called slotted spring pins) in the thin series. The standard applies to pins manufactured from steel or from austenitic or martensitic stainless steel with nominal diameters from 2 mm to 50 mm inclusive. It defines dimensional series, material and hardness requirements, mounting guidance and test methods to ensure consistent performance of these fasteners.
Key Topics
- Scope and sizes: Nominal diameters d = 2 mm to 50 mm (thin series) with standardized length ranges and common commercial lengths as referenced in the standard.
- Materials and heat treatment: Pins may be supplied in carbon steels, austenitic or martensitic stainless steels, or manganese-silicon steels. Hardness and heat-treatment requirements are specified; hardness testing is to be performed in accordance with ISO 6507-1 (Vickers method).
- Dimensions and tolerances: Detailed dimensions and tolerances for diameter, slot width and pin length are provided. Assembly holes must be drilled to the pin nominal diameter and tolerance class H12.
- Mounting rule: When mounted into the smallest permissible hole, the pin slot must not close completely, ensuring residual spring action and retention.
- Surface treatment: The standard advises care with coatings because of hydrogen embrittlement risks. Electrolytic plating and phosphating are discouraged unless special precautions are taken; consult ISO 4042 for coating procedures and hydrogen embrittlement mitigation.
- Mechanical testing and acceptance: Shear resistance testing is specified to follow ISO 8749. Acceptance and inspection procedures reference ISO 3269.
Applications
Slotted spring-type straight pins standardized by ISO 13337:2009 are used where resilient, interference-fit fasteners are required for locating, securing or aligning components. Typical practical applications include:
- Retaining shafts, pins and components in light-duty assemblies
- Positioning and locating parts during assembly and service
- Use in appliances, light machinery and instrumentation where a spring-action retention is advantageous
Benefits for designers and manufacturers:
- Interchangeability due to standard dimensions and tolerances
- Predictable mechanical performance through specified hardness and shear testing
- Material options (stainless or carbon steel) to match corrosion resistance and strength requirements
Related Standards
- ISO 8752 - Thick series slotted spring pins (compatibility and selection guidance between thin and thick series)
- ISO 8749 - Shear testing method for pins
- ISO 3269 - Reception inspection for fasteners
- ISO 4042 - Guidance on electroplated coatings and hydrogen embrittlement prevention
- ISO 6507-1 - Vickers hardness test method
Notes
Designation examples given in the standard illustrate the correct format for ordering (for example: Spring-type straight pin ISO 13337-6 × 30-St or ISO 13337-6 × 30-N-C for a non-interlocking martensitic stainless version). For procurement and design, refer to the full ISO 13337:2009 document for complete dimensional tables, material compositions and testing criteria.