Why is coolant used in milling operations?

Coolant is utilized in milling operations primarily to reduce heat build-up and improve tool life. When milling, the contact between the cutting tool and the workpiece generates significant heat due to friction and the cutting process itself. This heat can lead to premature wear of the cutting tool and can affect the dimensional accuracy and surface finish of the workpiece. By applying coolant, the heat is dissipated, resulting in lower temperatures during machining. This not only enhances the longevity of the cutting tool but also helps maintain the integrity of the machined surface, leading to better overall results in the milling operation.

Using coolant also facilitates the removal of chips from the cutting area, which can further prevent tool wear and ensure a smoother operation. Thus, the main purpose of coolant in milling is to manage temperature and enhance tool performance, making this answer the most relevant in the context of milling practices.