EP also sells gear tooth measuring devices called GEAR GAGES! Gear Gages reduce mistakes, save time and money when identifying and buying gears. These pitch templates can be found in nine sets to recognize all the regular pitch sizes: Diametral Pitch “DP”, Circular Pitch “CP”, Exterior Involute Splines, Metric Module “MOD”, Stub Tooth, Fine Pitches, Coarse Pitches and Unusual Pitches. Refer to the section on Equipment GAGES for catalog quantities when ordering.
MATERIAL recommended for worms is usually hardened steel and bronze for worm gears. However, depending on the application form unhardened metal worms operate adequately and more economically with cast iron worm gears at 50% horsepower ratings. Furthermore to steel and hardenedsteel, worms are available in stainless, aluminium, bronze and nylon; worm gears can be found in steel, hardened metal, stainless, light weight aluminum, nylon 
and non-metallic (phenolic).
Security PROVISION: Worm gearing should not be used as a locking mechanism to carry heavy weights where reversing action could cause harm or injury. In applications where potential harm is nonexistent and self-locking is preferred against backward rotation after that use of an individual thread worm with a minimal helix angle instantly locks the worm equipment drive against backward rotation.
RATIOS of worm equipment sets are dependant on dividing the amount of teeth in the apparatus by the amount of threads. Thus single threads yield higher ratios than multiple threads. All EP inc. worm equipment sets can be found with either still left or right hands threads. EP inc. worm gear sets can be found with Single, Dual, Triple and Qua-druple Threads.
LUBRICATION can be an essential factor to boost effectiveness in worm gearing. Worm gear action generates considerable high temperature, decreasing efficiency. The quantity of power transmitted at confirmed temperature improves as the performance of the gearing boosts. Proper lubrication enhances performance by reducing friction and heat.
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