Pins

About pins

Pins are unthreaded fasteners used to align, join, or secure components in an assembly. This category encompasses a variety of pin types, each designed for specific applications and load conditions. Dowel pins, precision-ground cylindrical fasteners, are primarily used for alignment and to prevent relative motion between parts, often specified by diameter tolerance (e.g., h6, m6) and length. Cotter pins, or split pins, are used to secure other fasteners like castellated nuts or clevis pins, preventing them from backing out; they are selected by diameter and effective length. Clevis pins are unthreaded, headed fasteners with a through-hole at the opposite end for a cotter pin, used to connect yoked or hinged components, specified by diameter, grip length, and head style. Roll pins (or spring pins) are hollow, slotted, or coiled cylindrical pins that exert radial force when inserted into a hole, providing a secure, shock-absorbing connection; they are categorized by nominal diameter, length, and material (e.g., carbon steel, stainless steel). Taper pins, with a specified taper ratio (e.g., 1:50), are used for precise positioning and light-duty fastening. Common materials across pin types include plain carbon steel, alloy steels, stainless steels (303, 304, 316), and brass, with finishes such as plain, zinc-plated, or phosphated.