Drillings and millings of cylinders are performed in operations on turning centers. Then, the drill holes are machined on the cylinder surfaces with offsets of the cutting positions from the workpiece axis. The paper presents an analytical model to predict the cutting force in drilling of cylinders. Three dimensional chip flow is interpreted as a piling of the orthogonal cuttings in the planes containing the cutting velocities and the chip flow velocities. In drilling, the chip flow models are made on the chisel and the lips. The chip flow directions are determined to minimize the cutting energies on the chisel and the lips. The workpiece model on the cylinder is defined by the cutting point with respect to the cylinder shape. The cutting force in drilling of a cylinder is compared with that in drilling of a plate. Then, the effect of the offset cutting points on the cutting force is discussed in terms of the resultant cutting force, which induces the machining error and the tool breakage.

This content is only available via PDF.
You do not currently have access to this content.