In a Worm Gearbox, Worm Reduction Gear Box, Worm Speed Reducer and Gear Motor Manufacturer, three to eleven gear teeth are typically in contact with the worm, depending upon the ratio. The increased number of driven gear teeth that are in contact with the worm significantly increases torque capacity also raises shock load resistance. In addition to increasing the number of driven gear teeth in contact with the worm, Worm Gearbox, Worm Reduction Gear Box, Worm Speed Reducer and Gear Motor Manufacturer also increases the contact area on each gear tooth. The actual areas of instantaneous contact between the worm threads and the driven gear tooth are lines. These lines of contact move across the face of the gear tooth as it progresses through its total time of mesh with the worm. The lines of contact in double-enveloping worm gearing are configured to increase the power transmission capability and reduce the stress on each gear tooth.

Working conditions

Two shafts for 90 ° Intersect, input speed must not be more than 1500 rpm.The working environment temperature should range from  0 ~ 40 ° C, when the environment temperature below 0 ° C or above 40 ° C.Before starting the lubricating oil to corresponding heating and cooling, The worm shafts, reverse operation can be positive.

Data sheet on CUW double enveloping worm gear reducer :

Advantage: 
The advantage of Sgr High Efficiency, Low Noice Cone Worm Series Worm Gearbox design are dramatic. First, the total load is divided among more individual gear teeth, and the load is further divided where teeth support two lines of contact. This superior load distribution greatly increases load carrying capacity. Second, the improved torque throughput allows a smaller reducer to produce the same amount of torque, resulting in size and weight savings.
Double-enveloping worm gearing can carry loads that would require much larger and heavier cylindrical worm gearing.

 Double-enveloping worm gearbox figure :

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