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Worms and Worm Gears: When your worm gear wears or breaks and you
need a replacement we will ask for the mating worm because it contains almost all of the information we need to
reverse engineer your worm gear. Without the worm we will not be able to reverse engineer
your worm gear.
Worms are the driving gear in a worm and worm gear set. EFFICIENCY of worm gear drives depends to a large extent on the helix
angle of the worm. Multiple thread worms and gears with higher helix
angle prove 25% to 50% more efficient than single thread worms. The
mesh or engagement of worms with worm gears produces a sliding
action causing considerable friction and greater loss of efficiency
beyond other types of gearing. The use of hardened and ground worm
swith bronze worm gears increases efficiency, but we'll make them out of just about any material you specify.
The number of threads on a worm and the number of teeth on
a worm gear will determine the ratio of your set. Ratios are determined by dividing the number of
teeth in the gear by the number of threads. Typically the number of threads on a worm are 1,2, and 4, but 3, 5, and 6 are out there
as well. To determine how many threads are on your worm just look at it from the top where the threads start and count the number of
starts.
LUBRICATION is an essential factor to improve efficiency in worm
gearing. Worm gear action generates considerable heat, decreasing
efficiency. The amount of power transmitted at a given temperature
increases as the efficiency of the gearing increases. Proper lubrication
enhances efficiency by reducing friction and heat.
SAFETY PROVISION: Worm gearing should not be used as a locking
mechanism to hold heavy weights where reversing action can cause
harm or injury. In applications where potential harm 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 gear
drive against backward rotation.