Oil gallery hole drilling in aluminum alloy engine blocks using minimum quantity lubricant (MQL) method

The effects of cutting tool (drill), cutting process, and delivery system (MQL) variables on workpiece surface temperature were investigated when oil gallery holes were deep drilled in aluminum alloy engine blocks using MQL methodology. The independent variables considered for the drill were point angle and drill body taper. The cutting process variables were cutting speed and feed rate. The MQL variables were compressed air pressure and oil delivery rate. An incomplete block design was utilized to develop an empirical model for workpiece surface temperature as a function of the above independent variables. The process was optimized for low workpiece surface temperature considering low cycle time and low built up edge. The calculated results indicated that cutting speed was the most dominant independent variable. It was concluded in this research that deep hole drilling using MQL can produce deep holes at significantly higher rate than conventional deep hole drilling because the investigated feed rate range demonstrated little or no impact on the workpiece surface temperature.;This applied research can help improve the environment, worker health and safety, system flexibility, coolant related cost, chips selling cost, and cycle time (productivity) in drilling oil gallery holes. Not only does it have the potential of becoming a benchmark for machining all other features in aluminum engine blocks using MQL methodology but also for machining other aluminum engine components.