EP also sells equipment tooth measuring products called Equipment GAGES! Gear Gages reduce mistakes, save money and time when identifying and purchasing gears. These pitch templates are available in 
nine sets to identify all the standard pitch sizes: Diametral Pitch “DP”, Circular Pitch “CP”, External Involute Splines, Metric Module “MOD”, Stub Tooth, Good Pitches, Coarse Pitches and Unusual Pitches. Make reference to the section on Equipment GAGES for catalog numbers when ordering.
Materials recommended for worms can be hardened steel and bronze for worm gears. Nevertheless, depending on the application unhardened metal worms operate adequately and more economically with cast iron worm gears at 50% horsepower ratings. Furthermore to metal and hardenedsteel, worms can be found in stainless, aluminium, bronze and nylon; worm gears are available in steel, hardened metal, stainless, light weight aluminum, nylon and nonmetallic (phenolic).
Basic safety PROVISION: Worm gearing should not be used as a locking mechanism to carry large weights where reversing actions 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 low helix angle instantly locks the worm gear 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 gear sets can be found with either left or right hand threads. EP inc. worm gear sets are offered with Single, Double, Triple and Qua-druple Threads.
LUBRICATION is an essential factor to improve efficiency in worm gearing. Worm equipment action generates considerable heat, decreasing efficiency. The quantity of power transmitted at confirmed temperature raises as the efficiency of the gearing raises. Proper lubrication enhances efficiency by reducing friction and heat.
Have you thought about Worm wheel gear as a normal part of your life?