Optimizing the economic efficiency by micro-drill life improvement during deep-hole drilling in the 212-Valve manufacturing process

Abstract

The micro-drilling process by robodrills in the production of valves at Waters Corporation is the bottleneck caused by the short drill life. This thesis analyzed the chip formation and removal during the process to improve the tool life. The effects of the tool materials, geometry and peck drilling procedures were investigated. Based on these studies, a new micro drill bit, TYl 30, was selected from the commercial market and the test results for drilling 0.2794 mm holes in the workpiece made of 316-stainless steel showed that it lasted for 120 holes, 5 times longer than the currently used drill bit. An experimental study on various peck drilling procedures demonstrated the advantage of the quadratic pecking procedure, further increasing the tool life by 2 times. Upon the implementation of the new drill bit and the quadratic pecking procedure, the 212-Valve production lead time is estimated to be reduced by 11% and the EDM process will not be starved since the bottleneck process has been improved.