In mechanical assemblies and in transfer of power these thread applications play a vital role. In milling machine worm& thread helps in indexing the job. The square thread is generally used for transferring power like screw jack, and lead screw of a thread in thread cutting.
External threads and internal threads are assembled together for different engineering uses.
Uses of screw thread
Screw threads are used as fasteners to hold together and dismantle components when needed.
To transmit motion on machines from one unit to another
To make accurate measurements
To apply pressure
to make adjustments