[sadaf]

I want to know what is the effect of pressure and ampere in the pump,
especially when one can design a pump of big capacity, he needs more ampere to run this pump, but  the process required not as much flow so  the consumer achieved by closing some percent of discharge valve of that particular pump, and the pressure increases what will it cause affect in Ampere of motor.
How flow affects  the Ampere of pump
How pressure affects the Ampere of Pump, especially in the cases where pressure can be achieved by partially closing the discharge valve of the centrifugal pump? Is any mathematical relationship is present?

I also want to know what is difference b/w rated horse power, Fluid Horse power,  Indicated Horse
Power and Break Horse power

with kind regards

[technologist]

For the prediction of actual result U need Characterisitic curves for the pump which is supplied by the manufacturer.
However, if U see them then Power consumption is always directly proportional to flow rate. It doesn't matter how do you control the flow. This is about proportionality of power but actual power consumption / m3 of flow may be high or low depending on type of flow control method.

[NZben]

I know this is a bit old now - but if you're still interested look at www.grundfos.com - use their "webcap" catalogue and it will show u direct relations to flow, pressure power consumption - even motor efficiency at that loading

[Donaldson Tan]

the break horsepower of a compressor is the rate of useful work done.

the horsepower is the rate of energy expended after taking in account of the break horsepower and inefficiencies.

[eugenedakin]

Hello sadaf,

Here is a link for the many definitions of horsepower:

http://en.wikipedia.org/wiki/Horsepower#Definition

Cheers,

Eugene