What is Rated Capacity

Rated capacity is the capacity of machine or plant. This capacity shows the maximum production power in plant but it can not be achieved due to shortage of time and spending time in rest or other refreshment. So, it is totally theoretical capacity. Sometime it is also called load capacity. One more thing, you should know that every machine have its own rated capacity which will be different from other machine. We can take the example of rated capacity of a pump.

Rated Capacity for a Pump

So a pump rated for 100 GPM, with a certain fluid, with a 2 year warranty will, on average, last for 2 years. So 10,000 pumps, some will last longer and some shorter than 2 years. maker replaces those that break, so he tries to make sure he over designs the pump so the highest possible % endure.

Let us say you need 200 GPM, simple, run the pump faster. You may have to run it 2.4 times as fast to get 2 times the output. So will it now last 2 years? Probably nor, bearings are running at 2.4 times rated speed,  are stressed. You may have excess cavitation by the occurrence of negative pressure in some places, this can cause pitting as cavities collapse with a focused spherical collapse wave.