Effect of minimum quantity lubrication (MQL) in drilling commercially used steels

Abstract

Minimum quantity lubrication (MOL) refers to the use of cutting fluids of only a minute amounHypically of a flow rate of 50 to 500 mllhour-which is about three to four orders of magnitude lower than ti1e amount commonly used in flood cooling condition, where, for example, up to 10 liters of fluid can be dispensed per minute. The concept of minimum quantity lubrication, sometimes referred to as near dry lubrication or micro lubrication, has been suggested since a decade ago as a means of addressing the issues of environmental intrusiveness and occupational hazards associated With the airborne culling fluid particles on factory shop floors. The minimization of cutting fluid also leads to economical benefits by way of saving lubricant costs and workpiece/tool/machine cleaning cycle time. Compared to the wet drilling, MQL drilling performed many superiors mainly due to high lubricant capacity. It also provides significant reduction in roundness deviation at the entrance and end of the holes and also taper values Furthermore, it prOVides environment friendlmess (maintaining neat, clean and dry working area, avoiding inconvenience and health hazards due to heat, smoke, fumes, gases etc. and preventing pollution of the surroundings) and improves the machinability characteristics.