Various functions of cutting fluids are
- Cutting fluid cools the work piece and tool by carrying away the heat generated during machining.
- It acts as lubricant at the friction zones, hence tool life increases.
- As friction get reduced, the forces and electricity power consumption decreases.
- Using cutting fluids produces better surface finish to the work piece.
- It causes to break the chips into small pieces.
- It washes away the chips from the tool.
- It prevents the corrosion of chips and machine.
- Improves dimensional accuracy and control on the work piece.
- It permits maximum cutting speed hence the time for machining reduce and cost of manufacturing increases.
Properties to be possessed by the cutting fluids are
- Cutting fluids should have low viscosity to permit free flow of the liquid.
- It should posses good lubricating properties.
- It should have high specific heat, high heat conductivity and high heat transfer coefficient.
- It should be non-corrosive to work and machine.
- It should be non-toxic to operating person.
- It should be odourless.
- It should stable in use and storage.
- It should be safe.
- It should permit clear view of the work operation.
Most commonly used cutting fluids are
- Cast Iron: No cutting fluids are used.
- Steels: Lord oil with mineral oil is used.
- Alloy steel: Sulphur brass oil with mineral oil is used.
- Copper: Soluble oil with 90 to 95% of water is used.
- Aluminium: Mineral oil with soluble oil cutting fluids are used as cutting fluids.