EP also sells gear tooth measuring devices called GEAR GAGES! Gear Gages decrease mistakes, save money and time when identifying and ordering gears. These pitch templates are available in nine sets to identify 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. Make reference to the section on GEAR GAGES for catalog figures when ordering.
MATERIAL recommended for worms is hardened steel and bronze for worm gears. Nevertheless, depending on the application unhardened steel worms operate adequately and more economically with cast iron worm gears at 50% horsepower ratings. In addition to steel and hardenedsteel, worms can be found in stainless, aluminum, bronze and nylon; worm gears are available in steel, hardened steel, stainless, aluminum, nylon and nonmetallic (phenolic).
SAFETY PROVISION: Worm gearing should not be used because a locking mechanism to hold weighty weights where reversing actions can cause harm or injury. In applications where potential damage is non-existent and self-locking 
is desired against backward rotation then use of a single thread worm with a low helix angle automatically locks the worm equipment drive against backward rotation.
RATIOS of worm gear sets are determined by dividing the number of teeth in the gear 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 left or right hand threads. EP inc. worm gear sets can be found with Single, Double, Triple and Qua-druple Threads.
LUBRICATION can be an essential factor to boost performance in worm gearing. Worm equipment action generates considerable temperature, decreasing efficiency. The quantity of power transmitted at a given temperature raises as the performance of the gearing increases. Proper lubrication enhances efficiency by reducing friction and high temperature.
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