Effects of cross-flow filtration and tramp oil removal on the components and performance properties of metalworking fluids

摘要

Cross-flow filtration combined with oil skimming and separation are techniques that will maintain the efficacy and cleanliness of a metalworking fluid for a longer useful lifetime. To demonstrate that such techniques have negligible deleterious effects on metalworking fluid integrity, an experimental machining system was set up to simulate continuous coolant turnover through a filtration element and an oil separation device Jo r periods representing 2-month and 4-month sump change-out cycles. The three metalworking fluid types tested were semi-synthetic, extreme pressure soluble oil, and chlorinated soluble oil. Hydraulic oil was used as a tramp oil contaminant at a level that reached 10%. Sump metalworking fluids were monitored for individual coolant ingredients, physical and aggregate properties, and performance properties. Most metalworking fluid components exhibited very minor changes in active levels, and none were depleted. For the duration of the test, the metalworking fluids exhibited no significant reductions in lubrication efficiency as measured by the Tapping Torque Test Machine. Additionally, no losses in corrosion protection were observed.