In the field of Mechanical engineering the term “machine” is defined as a mechanism or assembly of mechanisms that operates by utilizing electrical, mechanical and or pneumatic power and thereby reduces human effort.
The term machine includes wide ranges of machineries
However machine tool is not the same with the machine. Machine tools are such mechanisms that possess the following characteristics.
- Machine tools must be power driven.
- Machine tools must be non portable and are always firmly installed with the ground.
- Machine tools should utilize a cutting tool to shear off excess material from the workpiece or job in the form of chips.
- Machine tools should be able to perform more than one type of machining or metal cutting operations.
If all the above conditions are satisfied by a particular machine then it can be called as a machine tool.
Hence all the machine tools are machine ,but not vice versa. A hand drill is a machine but a pillar drill is said to be a machine tool.
**It is worth mentioning that usage of the phrase machine tool is confined to the metal cutting field only.