4 Common Types of Coil Springs

Compression spring by Monroe Engineering

Springs can be classified as either coil or non-coil, depending on their design. Coil springs live up to their namesake by featuring a coiled design. They are typically made of a single strand of metal that follows a helical path, resulting in a coil. Coil springs are made by wrapping the strand of metal around a cylinder. While all coil springs share this helical design, some of them have unique features that distinguish them from the rest. Below are four of the most common types of coil springs.

#1) Volute

There are volute coil springs. Volute is a type of compression coil spring that lives up to its namesake by featuring the shape of a volute. In other words, it’s shaped like a cone. Volute coil springs are used in applications involving a heavy load. They can withstand more pressure than other types of springs. When exposed to a heavy load, volute coil springs will become stiffer on the edge.

#2) Arc

There are also arc coil springs. Also known as bow springs, arc coil springs were originally developed for use in automotive and mechanical drive trains. As their name suggests, arc coil springs feature an arched shape. They don’t run completely straight from one end to the other end. Rather, arc coil springs are curved in the middle, thereby creating an arc shape. Arc coil springs can be connected to two objects, which will pull the objects together.

#3) Variable

Also known as progressive rate springs, variable springs are those with a variable rate. They are typically designed with different distances between their turns. When a variable coil spring is compressed, its rate of compression will change between its turns. Other types of coil springs have the same distance between their turns, so they have the same rate of compression.

#4) Torsion

Finally, torsion coil springs are those that are designed to withstand or resist twisting actions. A common example is a mousetrap. Traditional mousetraps are designed with a torsion coil spring. When twisted along the axis, the torsion coil spring will retain its mechanical energy. It will then release this energy when the lock is removed.

In Conclusion

There are different types of coil springs. Some of the most common types include volute, arc, variable and torsion. They all feature a coiled design. A coiled design is essentially what distinguishes them other types of springs. Nonetheless, each of these four types of coil springs are unique in their own way.