Cutting Fluid

Cutting fluid is a type of coolant and lubricant designed specifically for metalworking and machining processes. There are various kinds of cutting fluids, which include oils, oil-water emulsions, pastes, gels, aerosols (mists), and air or other gases. They may be made from petroleum distillates, animal fats, plant oils, water and air, or other raw ingredients. Depending on context and on which type of cutting fluid is being considered, it may be referred to as cutting fluid, cutting oil, cutting compound, coolant, or lubricant.

Most metalworking and machining processes can benefit from the use of cutting fluid, depending on workpiece material. Common exceptions to this are machining cast iron and brass, which are machined dry.

The properties that are sought after in a good cutting fluid are the ability to:

• keep the workpiece at a stable temperature (critical when working to close tolerances). Very warm is OK, but extremely hot or alternating hot-and-cold are avoided.
• maximize the life of the cutting tip by lubricating the working edge and reducing tip welding.
• ensure safety for the people handling it (toxicity, bacteria, fungi) and for the environment upon disposal.
• prevent rust on machine parts and cutters.