Spring, Presetting

When a compression spring has been coiled from a spring wire it is preset, cold or hot, coil-to-coil or to a defined length corresponding to a specified torsion stress in the wire. This is done to introduce a new stress situation in the wire, improving the spring load at a specified depression. The presetting also makes the spring “stand” better and reduces the loss of load over time. The process is also known as “scragging.”