When should coolant be used in a machining process?

Coolant should be used in a machining process primarily to cool heated areas and remove chips throughout the process because it serves essential functions that enhance performance and prolong tool life. As machining operations generate heat due to friction between the cutting tool and the workpiece, applying coolant mitigates this heat, which, if uncontrolled, could lead to tool wear, distortion of the workpiece, and possible failure of the machining operation.

Additionally, coolant aids in chip removal, which is critical for maintaining visibility and precision during machining. Efficient chip removal ensures that the cutting area remains clear, reducing the risk of re-cutting chips and improving surface finish quality. By keeping both the tool and workpiece temperatures stable, coolant helps ensure that the machining process operates effectively and efficiently.

The other options miss the broader applications and benefits of using coolant. For example, only using coolant during the initial setup does not account for the ongoing heat and chip management required throughout the machining process. Similarly, considering coolant unnecessary overlooks its vital role in maintaining performance and achieving high-quality results in various machining tasks, not limited to non-metal materials.