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Strijdom Park, Randburg.
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  • Sewage Pumps
  • Zuwa Pumps


What is pump efficiency?

When we talk about the efficiency of most types of machines, we are usually referring to how well it can convert one form of energy to another. If there is one unit of energy supplied to the machine and its output, in the same units of measure, is one half unit, the efficiency of it is 50%.

What exactly is specific speed and how does it affect the pump curve?

Specific speed was first applied to centrifugal pumps and was then a modified version of one developed for water turbines. You will find that most pump designers tend to see specific speed as the most important contributor to centrifugal pump design, allowing the use of existing design and the test data in order to design similar higher and lower flow pumps as the specific speed of a pump is independent of the size.

How does the curve shape of a pump affect the efficiency?

The typical performance curve is basically flat at low values of specific speed and it will become steeper as the Ns increases. The pump efficiency is lowest at low values of Ns and it will increase as the Ns increases. It reaches its max in the mid-to-high 2000 range and it will also begin to decrease above 3000. For more questions about pumps, contact Ernest Electro Engineering today!