Ever thought of using disc spring washers as compression springs in tool and die making? A disc spring is best use in situations whereby the tooling requires higher spring force but constrain by space limitation or when incorporating a nitrogen gas spring is not possible.

A disc spring is a conical shell. It can be loaded along its axis either statically or dynamically. The loads are normally applied to the upper inner edge and the lower outer edge. Disc springs can be used either in a stack or in a single piece.

Disc springs can be stacked in the opposite direction face to face to each other (series arrangement), which means their deflections add up, it allow longer travel length. They can also be stacked in the same direction (parallel arrangement) allowing the force to add up but still remain the same travel length.

Disc springs are usually guided with a hardened shaft going through from the centre hole of the disc. The surface of guide elements must always be hardened, harder than the disc springs themselves. A minimum of 55 HRC is usually recommended.

I have tried using disc springs on one of the blank holders of a first draw station in one of a progressive deep drawn tool. This tool had been running for 50,000 parts without any problem arising. The design of the tool is shown below.

Disc springs are available in any local hardware stores