Lubrication

Removal of heat

Hold lapping compound

Increase the efficiency

Sunk key

Flat saddle key

Circular taper key

Hallow saddle key

Taps

Drills

Turning tool

Reamers

To add cutting ability

To develop high hardness

To remove stress and strain

To increase wear resistance

Annealing

Tempering

Hardening

Normalising