Extension Spring Ends

Extension Spring Design Resources – Custom Spring End Configurations

Extension springs require a method of attachment to other parts in an assembly. A wide variety of ends have been developed and used to successfully for many years – for example, threaded inserts, swivel hooks, twist loops, side loops, cross-center loops and extended hooks. Loops are attachment ends that have small gaps, while hooks are loops with a large gap. In fact, the variety of ends is almost unlimited. The most common configurations are those that can be formed during the spring making operation. Typical types include twist, cross center, side loops and extended hooks. Many of these configurations are made by bending the last coils of an extension spring to form loops. Most special hooks are formed from straight sections of wire on the so-called "tangent ends" of an extension spring body.