When shopping for aerospace fasteners, you may come across spring pins. Also known as slotted pins, they are commonly used in airplanes. Airplanes require fasteners to hold their respective parts together. In addition to screws, bolts and rivets, many airplanes feature spring pins. What are spring pins exactly, and how do they work?
What Are Spring Pins?
Spring pins are cylindrical-shaped fasteners that are designed to secure two or more parts together. They feature chamfered ends while allowing for a spring-like action. Spring pins essentially have a large slit, which allows them to deform under pressure.
In airplanes, spring pins are typically used to hold multiple parts together in a position where the parts are relative to each other. Spring pins can be inserted into holes running through the parts. Once inserted, they’ll hold the parts together while ensuring that the part maintains their relative position.
How Spring Pins Work
Spring pins work by filling the space of the hole in which they are placed while attempting to expand. They are known as “spring pins” because they are rod-like pins that act like springs. They will deform under pressure, and during this process, spring pins will attempt to expand by releasing the mechanical energy of this pressure.
Upon placing a spring pin in a hole, it will expand. Spring pins are chamfered, meaning their diameter changes from one end to the other end. With their chamfered design, spring pins will compress while filling the space of the hole. In doing so, spring pins will exert a force against the inner walls of the hole.
There are two primary types of spring pins:
- Coiled spring pins: One of the most common type of spring pin is coiled. Coiled spring pins are characterized by a coiled construction. Most of them are made of metal or a metal alloy.
- Slotted spring pins: There are also slotted spring pins. Slotted spring pins are cylindrical-shaped pins with a slot running down them.
In Conclusion
After reading this, you should have a better understanding of spring pins. They are fasteners that leverage a spring-like action to hold multiple parts together. Spring pins are chamfered so that they attempt to expand when placed inside of a hole. While they are available in dozens of styles, most spring pins fall under one of two categories: coiled or slotted.
