Metalworking fluid (MWF) is the name given to a range of oils and other liquids that are used to cool and/or lubricate metal workpieces when they are being machined, ground, milled, etc. Metalworking fluids reduce the heat and friction between the cutting tool and the workpiece and help prevent burning and smoking. Applying MWFs also helps improve the quality of the workpiece by continuously removing the fines, chips, and swarfs from the tool being used and the surface of the workpiece. (Swarfs are the small pieces of metal removed from a workpiece by a cutting tool.)
Although each class will vary greatly in composition, each may contain additives such as
- Corrosion inhibitors.
- Extreme pressure additives.
- Anti-mist agents (e.g., polyisobutylene polymer).
- Anti-weld agents.
- Emulsifiers (e.g., triethanolamine, sodium petroleum sulphonates, salts of fatty acids, and nonionic surfactants).
- Biocides (e.g., triazine compounds, oxazolidine compounds).