STAINLESS STEEL SPLIT PINS DIN 94

Split Pins DIN 94 — Split Pins to DIN 94 — also called cotter pins — are a length of wire folded double and pushed through a cross-drilled hole, then splayed open at the two legs to lock in place; unlike the pins above, they aren't meant to locate components precisely or carry load, they exist purely to stop something else (usually a nut or a clevis pin) from working its way off. The single most common application is securing a castellated or slotted nut on a bolt or shaft, where the pin passes through both the nut's slots and a hole in the bolt, so the nut physically cannot rotate loose; they're equally used to retain clevis pins in linkages, secure fork-end connections, and generally provide a last-line mechanical safety lock in assemblies subject to vibration or movement, across automotive, agricultural, and general mechanical engineering. Because the pin works by permanent deformation of its legs rather than friction, elasticity, or a tight tolerance fit, sizing is straightforward compared with dowel or spring pins: diameter is selected to suit the cross-hole it passes through (commonly matched to the bolt or clevis pin size via published tables), and length needs enough spare beyond the hole to bend the legs back around the nut or fitting without fouling adjacent components. Grade matters here more for durability than strength, since the pin isn't load-bearing: A2 stainless is standard for general use, while A4 is worth choosing for split pins on outdoor, marine, or washdown equipment, since a corroded or pitted pin becomes brittle at the bend and more likely to snap on removal, defeating the point of a safety lock that needs to be replaced cleanly at each service interval. Because bending fatigues the metal at the fold, a split pin should be treated as a single-use item wherever it's part of a genuine safety retention, rather than straightened and reused.

FAQs
Are DIN 94 split pins suitable for load-bearing applications?
No. They are locking or safety devices only, not designed to carry tensile load, and should never be relied on as a structural fastener.

How much of the leg should be bent back after installation?
Enough to prevent the pin working back out through the hole — typically one leg is bent over the end of the bolt or shaft and the other around the side, without over-bending, which weakens the wire unnecessarily at the fold.

Are DIN 94 split pins reusable?
They can technically be straightened and reused once, but each bend cycle fatigues the metal at the fold; for safety-critical retention such as a castellated nut on a rotating or load-bearing assembly, fitting a new pin at each service is the safer practice.