Mechanics of Punching Circular Holes in Materials for Data Handling

A theoretical model is developed in an effort to predict the effect of various design and operating parameters on the mechanics of punching circular holes in relatively ductile, nonmetallic materials which are commonly used in data-handling equipment. Solutions are obtained for the various punch geometries most frequently used. Experimental results for punching force versus punch displacement, maximum punching force, and total energy expended during punching are in good agreement with the theoretical solutions. Although this work is primarily concerned with circular holes, the theoretical approach used is equally applicable to the punching of other hole geometries, such as rectangular holes. The possibility of extending the theoretical treatment to metal punching is also discussed briefly.