A review on coolants and their application in deep-hole drilling operation

Deep Hole Drilling involves drilling a hole through the thickness of the component, measuring the diameter of the hole, trepanning (cutting a circular slot around the hole) a core of material from around the hole. During drilling operation, friction between work piece-cutting tool and cutting tool-chip interfaces result high temperature on cutting tool. The effect of this generated heat affects shorter tool life, higher surface roughness and lowers the dimensional sensitiveness of work material. Thus, Increased tool wear being a natural phenomenon in all machining processes leads to tool failure. There is growing demand in machining process for high productivity with use of high cutting velocity and feed rate. Such machining inherently produces high cutting temperature. The performances of machining operations are changed by use metal cutting fluids because of their lubrication, cooling and chip flushing functions. Cooling lubrication is an essential condition to achieve the economical tool life and the required surface quality in many cases. As they are used to provide lubrication and cooling effects between cutting tool and work piece and cutting tool and chip during machining operation. Hence the influence of generated heat on cutting tool would be prevented. This paper deals with review on coolants and their application in deep-hole drilling operation.