Effect of Canned Cycles on Drilled Hole Quality

摘要

Several factors influence the accuracy of drilled holes. The most obvious ones are the cutting conditions (cutting speed and feed rate) and cutting configurations (tool material, diameter, and geometry). As such, most previous studies have concentrated on these factors. However, in CNC drilling operations, choosing to use canned cycles may have significant effect on drilled hole quality. The objective of this project is to explore this possibility in detail. This paper presents experimental and analytical results of an investigation into the dimensional accuracy and surface finish of drilled holes using different canned cycles. A traditional analysis, the Pareto ANOVA, and the Taguchi S/N ratio are employed to determine the effects of the three major input parameters (cutting speed, feed rate, and canned cycle) on three key accuracy characteristics of drilled holes (diameter error, circularity, and surface roughness), as well as to obtain an optimal combination of the input parameters. The work and tool materials selected are aluminum 6061 and high-speed steel (HSS), respectively. The results indicate that the canned cycle has a profound effect on drilled hole quality, and, in general, canned cycle spot drilling produces the best results.