The most common metalworking fluids used today belong to one of two categories:
Cutting fluids play a significant role in machining operations and impact shop productivity, tool life and quality of work. The primary function of cutting fluid is temperature control through cooling and lubrication [Aronson, et al., 1994]. A fluid's cooling and lubrication properties are critical in decreasing tool wear and extending tool life. Cooling and lubrication are also important in achieving the desired size, finish and shape of the workpiece [Sluhan, 1994]. A secondary function of cutting fluid is to flush away chips and metal fines from the tool/workpiece interface to prevent a finished surface from becoming marred and also to reduce the occurrence of built-up edge (BUE).
Monitoring and maintenance of cutting fluid is required due to contamination and degradation. Eventually, fluids require disposal once their efficiency is lost. Waste management and disposal become a major problem concerning environmental liability. The primary concern is the significant negative effects to worker's health associated with use of the cutting fluids.