THE EFFECT OF PUNCH RADIUS AND HOLE LOCATION ON THE SPRING BACK OF COMPONENTS WITH HOLES ON BENDING SURFACES

Sheet metal bending processes are used frequently in manufacturing operations. One of the problems in these operations is the spring back estimation, particularly when producing components with strict tolerances. The situation becomes even more complicated if the components have any holes on the bending surfaces. In this paper the influence of the punch radius and hole location on the spring back for components which have an oblong shape hole on the bending surface are studied experimentally and compared with parts without holes on the bending surfaces. The material used for the components are High Strength Low Alloy Steel. The dies used are V-shape dies. The results show the existence of a hole and also that its location on the bending surface plays an important role in the spring back and hence the final bending angle of the component. The results show that the punch radius too has an important effect on the spring back