Development of a drilling burr control chart for low alloy steel, AISI 4118

A control chart for drilling bun formation for low alloy steel, AISI 4118, was developed. A drilling burr control chart, based on experimental data, is a tool for the prediction and control of drilling burrs. High-speed steel split-point twist drills with different diameters were used for the tests. Fun classification was carried out based on the geometric characteristics, bun formation mechanisms, and sizes of the burrs. Four different bun types such as uniform bun (Types I and II), transient burn and crown bun were found. New parameters consisting of process parameters and drill diameter were developed, and used to show a unique distribution of the bun types. Bun types and the resultant bun size showed great dependence on the new parameters regardless of the drill diameter. Through thr chart, bun type can be predicted as a function of given cutting conditions. Also, cutting conditions that are believed to create preferred bun types can be selected. (C) 2001 Elsevier Science B.V. All rights reserved.