MQL in Milling

The five-axis machining centre at KTH Royal Institute of Technology, Department of Production Engineering is now equipped with a MQL (minimum quantity lubrication) system with the possibility to apply MQL both internally through the tool as well as externally through nozzles. The PMH Application Lab thanks Accu-Svenska AB for supporting us with the equipmentand its installation. This has been done as part of the project “ Design of a testbed for sustainable milling with minimum quantity lubrication ” funded by Vinnova. The next step in the project is using the equipment in a simplified experimental set-up design inorder to carry out a follow-up study at KTH. The long-term goal of the projects is to assess the validity of MQL in milling.

MQL means using only a small amount of coolant to achieve lubrication and cooling of both the tool and the material being processed in a machining operation. So far, MQL has been implemented for drilling, turning and grinding operations. However, MQL is still not widely used in milling operations, and faces challenges for implementation.

Several major European companies indicated that about 16% of total manufacturing expenses are related to coolants. MQL could help to reduce the amount of coolants used by up to 95%. Substitution of traditional coolant by MQL has the potential to drastically reduce the amount of coolants being used, which would result in considerable cost reduction, decrease the environmental impact of machining processes and better working conditions for machine operators.

See an example of a milling operation with the MQL equipment from the PMH testbed: