Studies on minimum quantity lubrication (MQL) and air cooling at drilling

In the recent years a lot has been done to avoid the cutting fluids from the production. Dry cutting and semi-dry cutting such as minimum quantity lubrication (MQL) have been favored by the industry. However, one of the main limitations in the application of MQL is that the full mechanism has not yet been fully understood. This paper deals with the results obtained at cutting with MQL at different oil amounts, dry compressed air and emulsion. The results are discussed in terms of wear, chip contact, forces/torques and surface finish. The short hole drilling tests with indexable inserts showed that MQL and compressed air usage have resulted lower wear both on the center and periphery insert compared to drilling with emulsion. The surface finish values have shown that; cutting with compressed air resulted in side flow and sticking of the work piece material on the walls of the hole that gave bad surface finish. The longer chips were evidenced for emulsion in comparison to MQL and air assisted drilling.