The primary advantage of worm gears is their capability to provide high reduction ratios and correspondingly high torque multiplication. They may also be applied as velocity reducers in low- to medium-velocity applications. And, because their reduction ratio is based on the amount of gear teeth by itself, they are smaller sized than other styles of gears. Like fine-pitch business lead screws, worm gears are usually self-locking, which makes them perfect for hoisting and lifting applications.
Although the sliding contact reduces efficiency, it provides incredibly quiet operation. (The usage of dissimilar metals for the worm and gear also plays a part in quiet procedure.) This makes worm gears suitable for use where noise should be minimized, such as for example in elevators. Furthermore, the use of a softer material for the apparatus means that it can absorb shock loads, like those experienced in major equipment or crushing devices.
The meshing of the worm and the gear is an assortment of sliding and rolling actions, but sliding contact dominates at high reduction ratios. This sliding action causes friction 
and warmth, which limits the performance of worm gears to 30 to 50 percent. In order to minimize friction (and therefore, warmth), the worm and gear are made from dissimilar metals – for example, the worm could be made of hardened steel and the gear manufactured from bronze or aluminum.
Like a ball screw, the worm in a worm gear may have a single start or multiple starts – meaning that there are multiple threads, or helicies, on the worm. For a single-start worm, each complete convert (360 degrees) of the worm advances the gear by one tooth. Therefore a gear with 24 teeth will provide a gear reduction of 24:1. For a multi-commence worm, the gear reduction equals the amount of teeth on the apparatus, divided by the number of starts on the worm. (This is different from almost every other types of gears, where in fact the gear reduction is normally a function of the diameters of both components.)
Worm Gear Shaft is utilized to fit in any kind of everyday regimen.