STAINLESS STEEL SPLIT PINS DIN 94

Split Pins – DIN 94 – FAQs

What is a DIN 94 split pin?

A DIN 94 split pin is a simple mechanical locking device, formed from wire bent into two legs with a closed eye at one end. The pin is inserted through a transverse hole in a shaft, bolt, or clevis pin and secured by bending the legs apart.

Split pins manufactured to DIN 94 conform to defined dimensions and tolerances and are also commonly referred to as cotter pins.

What are DIN 94 split pins used for?

DIN 94 split pins are commonly used:

  • To prevent axial movement of components
  • As a safety locking device on bolts, shafts, and clevis pins
  • To secure castle nuts or slotted nuts
  • In assemblies subject to vibration or movement
  • In mechanical, automotive, agricultural, and general engineering applications

They are designed to provide retention rather than precise alignment. 

How do DIN 94 split pins work?

Once inserted through a hole, the two legs of the split pin are separated and bent back. This prevents the pin from being withdrawn and provides a simple but effective mechanical lock.

The pin relies entirely on physical deformation of the legs rather than friction or spring force. 

Are DIN 94 split pins reusable?

DIN 94 split pins are intended for limited or single‑use applications. Repeated bending can cause metal fatigue, reducing their effectiveness. For safety‑critical applications, split pins should be replaced after removal. 

What materials are DIN 94 split pins available in?

DIN 94 split pins are commonly supplied in:

  • Stainless steel

Material choice depends on environmental conditions and corrosion resistance requirements.

What sizes are available?

DIN 94 split pins are supplied in a wide range of metric diameters and lengths, defined by the standard. Sizes are specified by:

  • Nominal pin diameter
  • Overall pin length

Dimensions and tolerances are governed by DIN 94.

How are DIN 94 split pins installed?

Split pins are installed by:

  1. Inserting the pin through a pre‑drilled hole
  2. Pulling the pin fully home so the eye contacts the surface
  3. Bending the two legs back in opposite directions

No specialist tools or presses are required.

Are DIN 94 split pins suitable for load‑bearing applications?

No. DIN 94 split pins are intended as locking or safety devices only. They are not designed to carry tensile loads and should not be used as structural fasteners. 

How do DIN 94 split pins differ from spring pins?

  • Split pins (DIN 94) rely on bending the legs to lock the pin in place
  • Spring pins (ISO 8752) rely on elastic spring force against the hole wall

Split pins are typically used as secondary safety retainers, whereas spring pins are used for press‑fit retention.

How do I choose the correct DIN 94 split pin?

When selecting a DIN 94 split pin, consider:

  • Pin diameter to suit the hole size
  • Pin length, ensuring sufficient leg length to bend securely
  • Material selection for corrosion resistance
  • Whether the split pin will act as a secondary safety device