What Does 'Nominal' Mean in Gear Drive Reducer Specifications?

[bananabrownin]

When searching through a catalog for gear drive reducers, I find that many of them list nominal output torque and nominal input speed. My question is what does the term 'nominal' in that context mean.

If it lists nominal output torque of 3186in.lb, and nominal input speed of 2900rpm, does that mean it will only output 3186in.lb with a 2900rpm motor attached? What if a 1hp 1750rpm motor was attached to that gear drive reducer?


Thanks

 

[Mech_Engineer]

If it lists nominal output torque of 3186in.lb, and nominal input speed of 2900rpm, does that mean it will only output 3186in.lb with a 2900rpm motor attached? What if a 1hp 1750rpm motor was attached to that gear drive reducer?

They are probably referring to the maximum allowed torque on the gearbox before it breaks, and the maximum (or possibly "recommended") rpm rating of the motor attached to it. So you can't use a motor that goes faster than 2900rpm, and the motors maximum developed torque cannot be higher than (3186 in-lb) / N where N is the gear reduction of the gearbox. So if the gearbox was 1000:1 for example, the motor could not develop more than 3.186 in-lb without damaging the gearbox.