Minimum Quantity Lubrication for Sustainable Machining Chapter uri icon


  • 2017 Elsevier Inc. All rights reserved. Minimum quantity lubrication (MQL) machining refers to using a small amount of metal working fluid to achieve both lubrication and cooling between the cutting tool and work material, in contrast to traditional flood and high-pressure water-based coolants. Water-based coolants are recirculating emulsions or solutions of water and oil at flow rates of several L/min and pressures up to 100. bar, while MQL consumes the lubricant (typically straight oil) at 5"300. mL/H at air pressures between 4 and 10. bar. The fluid consumption of MQL is lower by three to four orders of magnitude than in wet machining, and the MQL oil is also consumed in the process, so no coolant pump, cooling, or filtering is required. This significantly reduces energy consumption and costs associated with coolant disposal, reclamation, filtration, and chilling. A report from German Social Accident Insurance, which involved several major European companies, indicated that about 16% of total manufacturing expenses are related to cutting fluid. Ford Motor Company, a large MQL user and a leader in the implementation of MQL in high volume production, has also reported that the flood cooling costs are in the range of 10%"17% of the total powertrain manufacturing costs. As a result, MQL has seen increasing use in automotive powertrain machining and in the machining of airframe and other large structural components.

author list (cited authors)

  • Tai, B., Stephenson, D., Furness, R., & Shih, A.

citation count

  • 16

complete list of authors

  • Tai, Bruce||Stephenson, David||Furness, Richard||Shih, Albert

Book Title

  • Encyclopedia of Sustainable Technologies

publication date

  • July 2017