Investigation of Chip Formation on Drill Edge under Wet and Dry Cutting

Abstract

This paper investigated an angle and a velocity of chip flow on a standard point shape drill under wet and dry cutting. The angle was gotten from a video image into cutting and the velocity was calculated from the length of chip after cutting and its corresponding time. Observed characteristics of the chip when a chip passes cutting edge was as follows. The angle nearby the middle of the edge under dry cutting is larger than that under wet cutting and the change of the velocity under dry cutting is smaller than that under wet cutting. When a chip passes the rake face under dry cutting, the chip part at chisel edge side is more separated to the direction of chip flow than that under wet cutting. It was found that the chip formation of dry cutting is better than that of wet cutting for getting long pitch type chip.