Springs are commonly used as machine elements which often provide support and cushioning effect to moving or vibrating parts. They also serve as force or torque transmission elements in which case shock is minimized. Springs also work as mechanical storage of energy and as shock absorbers.
Various types of springs are in use but the commonest is the close-coiled helical spring. A close-coiled helical spring is made by coiling a uniform diameter wire on a mandril. The coiles are laid close to each other, almost touching each other and the wire diameter is small in comparison to the mandril diameter on which the wire is wounded. Once coiled, the spring may open slightly due to “spring back” action thus increasing ...