Simple Estimation Method of Cutting Forces in Cylindrical Turning

Abstract

For the purpose of developing a new simple estimation method of metal cutting forces, firstly, orthogonal cutting data are examined from the point of view that material constants other than shear stress on the shear plane, which is characteristic of the material used and is not affected by cutting conditions, may exist. As a result, the authors find that the principal cutting force is approximately proportional to the chip thickness in a relatively wide range of cutting conditions. Thus, the principal cutting force is proportional to the unit chip sectional area, and the proportional constant is named “ chip constant ” for convenience in this paper. Then, the concept of the chip constant is introduced into the cutting mechanism of cylindrical turning, and three cutting force components are analyzed. The estimated values of the three components are compared with measured ones in regard to the change of side cutting edge angle. Since only two constants of the material used, i.e., the chip constant and shear stress assumed from the chip hardness, and measurement of the chip thickness are required, this estimation method of cutting forces is simple and handy.