ISO is the governing dimensional standard for split cotter pin. This page sets out the scope of the standard, reproduces the full size table it specifies, and lists the DIN/ISO/ASME cross-references commonly cited in datasheets and drawings.
ISO — Scope
ISO specifies the dimensions and tolerances of split cotter pin — iso / din (series 102). Material, property class, surface finish and packaging are governed by separate documents in the same standards family (for example ISO 898-1 for the mechanical property classes of bolts and screws).
Tolerance & Product Grades
ISO, alongside the related ISO / DIN entries on this site, specifies product grades (typically A or B for fine work and C for general engineering) and tolerance classes for the controlling dimensions. Choose the grade against the precision your application requires.
Dimensions Specified by ISO
| Nominal diameter (mm) | Length L (mm) | Material | Reference standard |
|---|---|---|---|
| 1.0 | 16 | Carbon steel | ISO 1234 / GB/T 91 |
| 1.2 | 20 | Carbon steel | ISO 1234 / GB/T 91 |
| 1.6 | 25 | Carbon steel | ISO 1234 / GB/T 91 |
| 2.0 | 32 | Carbon steel | ISO 1234 / GB/T 91 |
| 2.5 | 40 | Carbon steel | ISO 1234 / GB/T 91 |
| 3.2 | 50 | Carbon steel | ISO 1234 / GB/T 91 |
| 4.0 | 63 | Carbon steel | ISO 1234 / GB/T 91 |
| 5.0 | 80 | Carbon steel | ISO 1234 / GB/T 91 |
| 6.3 | 100 | Carbon steel | ISO 1234 / GB/T 91 |
| 8.0 | 125 | Carbon steel | ISO 1234 / GB/T 91 |
Companion Standards
ISO controls only the geometry of split cotter pin — iso / din (series 102). The mechanical strength is set by ISO 898-1 (bolts and screws) or ISO 898-2 (nuts); the surface finish is governed by separate finish standards (e.g. ISO 4042 for electroplating). For corrosion testing, the relevant document is ISO 9227 (neutral salt spray).
When to Specify ISO
Choose ISO for international engineering work and OEM supply where ISO standards are the contractual reference. It is the default modern specification for split cotter pin — iso / din (series 102).