The mechanical capacity of worm gear reducer is generally based on the endurance limit of the material surface gear bronze, and the hardness and surface finish of the steel worm. In some low speed, high torque applications, can the shear strength of the material gears limiting factor. Calculating mechanical catalog ratings to be used with a service factor of 1.0. This is for intermittent or continuous service free from shock loading, and a total length of up to 10 hours per day. Require applications outside these conditions appropriate service factors modify the allowable unit ratings. Table 1 defines the service factors for different operating conditions.
Section A lists the AGMA service factors for different applications. The thermal capacity of worm gear reducer the actual horsepower (without service factor), the reducer will transmit continuously for 2 hours or more without the oil temperature exceeding 200 deg F. The housing and leverage improvements in Powercube allow continuous operation at higher horsepower. In addition, the ability of high temperature seals standard and optional synthetic oils reducers operating in more than 225 deg F continuously to maximize the thermal capacity.
Thermal ratings can be ignored when the continuous operating time of more than 2 hours and represents the shutdown period or over the operating period. However, when this operating period of 2 hours, or over the operating period of the shutdown period, thermal ratings must be included. Reducer should choose a thermal rating that meets or exceeds the ACTUAL horsepower to be transmitted. Synthetic oils increase the thermal rating, and allow smaller units to be selected. The housings more and better leverage, with the appropriate synthetic oil, making unnecessary cooling fan of the series 380 and less. Cooling fan is available on the 450 series and more still.
That the thermal ratings assume ambient temperature of about 75 deg F. For higher ambient temperature, thermal ratings will be about 1% less, per degree above 75 deg F. Worm gear units are run- in a period of about 50 hours. The polished worms improve the efficiency front, but the units could run hotter during the run-in period. Abnormal heat not necessarily mean that the unit is longer than the thermal capacity, unless there is excessive heating or persists longer than the run-in period.
