Tension pins, also known as spring pins or roll pins, are mechanical fasteners that secure the position of two or more parts of a machine relative to each other.

Tension pins have a body diameter larger than the hole they are intended for. They feature chamfers on either one or both ends to facilitate starting the pin into the hole. The spring action of the pin allows it to compress as it assumes the diameter of the hole. The force exerted by the pin against the hole wall retains it in place, making it a self-retaining fastener.

Tension pins can be used for various purposes:

• Retaining a shaft as a journal in a plain bearing.
• Fastening one shaft to another (acting like a key).
• Precisely fastening flat faces of mating parts together through symmetric hole locations.

The automotive, electrical, and manufacturing industries commonly use tension pins for various applications, including securing components, acting as hinge pins, and fastening multiple parts together. If you need further assistance or have any other questions, feel free to ask!