How Extention Springs Work, Extension Spring Applications

Extension springs resist a force pulling the spring apart. To accomplish this, an extension spring has to have a hook or other special “end” on each side of the spring to connect it to the load.

A predefined load can be built into the spring when it is wound. This is a load that must be overcome before the spring starts to deform – that is stretch. These defined loads are part of the design specification of an extension spring.

In practice, most extension springs are tightly wound from smaller gauge wire. Many sizes, materials, and preloads are available from Spring Products.

An extension spring operates in tension. The spring tries to return to its wound position and thus provides a force that increases as the spring is extended. Accordingly these springs are used in applications that need a force to return the unit from an extended position.

Note that a compression spring actually has the opposite action of the extension spring – compression springs must be compressed to store energy.

A trampoline is a good example of extension springs in use. The springs all around the surface extend as the load is applied, store the energy applied and return the surface and the jumper to the upper rest position – with a bounce!

Extension springs can be overextended and will then not return to the original at rest position so proper sizing is important.

For high quality extension springs for your application, custom or stock, please contact us at Spring Products.