Extension Springs are in many ways similar to helical compression springs, but with the major difference that the length increase with force. The spring ends must allow for a tension force to act, which typically means bending the ends of the wire to a hook. Many different end geometries are possible.
The coils of a cold-coiled tension spring are normally close coiled with an initial force between the coils, which reduces the installed length of the spring.
Material grades are the same as for helical compression springs, covering the whole range from normal spring steel to nickel alloys, titanium alloys and copper alloys. We cold coil tension springs up to wire diameter 18 mm. Hot coiled tension springs are not common, but possible for some end shapes.
The winding body and eyelet or hook shape of a helical tension spring depend on, and can be customised in line with, its function and the available installation space.
Production Wire forming machines
Spring coiling machines followed by manual bending
Special materials after individual consultation.
Dimensions Wire diameter 0.2 to 18 mm for cold-coiled tension springs
Customised versions and bespoke dimensions are possible after individual consultation.
John While Springs (S) Pte Ltd
1, Kallang Sector #03-02