Nipping Of Leaf Springs
As discussed in the previous section, the stresses in extra full length leaves are 50% more than the stresses in graduated –length leaves. One of the methods of equalizing the stresses in different leaves is to pre-stress the spring.
The pre-stressing is achieved by bending the leaves to different radii of curvature, before they are assembled with the centre clip.
As shown in Figure the full-length leaf is given a greater radius of curvature than the adjacent leaf
The radius of curvature decreases with shorter leaves.
The initial gap C between the extra full-length leaf and the graduated-length leaf before the assembly is called a nip.
Such pre-stressing, achieved by a difference in radii of curvature, is known as nipping.