Worm gears are very useful gear for mining and other industries, Worm gears are used when large gear reductions are required. Worm gear has a exclusive property of easily turning the gear. The gear cannot turn the worm because the angle on the worm is shallow and when the gear tries to spin the worm, the friction between the two holds the worm in place. Worm gears work under difficult conditions, presenting unique lubrication demands the oils which is most commonly used to lubricate worm gears are compounded mineral oils, EP mineral gear oils and synthetics.