Coolant shoe development for high efficiency grinding

Abstract

The combination of ultra hard abrasives and the high speed grinding process enables the fragmentation of chips into smaller size to accommodate a higher feed rate. However, the application of high efficiency grinding depends to a large extent upon the method of grinding fluid delivery. The formation of an air curtain layer around the grinding wheel prevents the entry of coolant to the grinding zone. This paper reports the characteristics of the air curtain layer that encompasses the grinding wheel. Also a new kind of coolant shoe is proposed and the performance output such as the grinding forces, power flux, surface integrity, wheel wear, microstructure and applications are reported. Such shoe possesses three adjustable orifice jets. The upper orifice breaks the air curtain and thus creates a vacuum enabling the sudden flow of coolant to the grinding zone. The middle orifice supply the coolant that leads to the formation of a coolant coating on the grinding wheel. The lower orifice directly impinges onto the grinding zone. Steady and laminar flow of coolant enable an increase of the coolant velocity and ensure the continuous supply of coolant to the grinding zone.