Pumps curves Videos
When selecting a centrifugal pump, one should match the performance of the pump to that needed by the system. To do that, an engineer would refer to a pumps composite curve. A typical composite curve includes the pump performance curves, horsepower curves and NPSH required. A pump performance curve indicates how a pump will perform in regards to pressure head and flow. A curve is defined for a specific operating speed (rpm) and a specific inlet/outlet diameter
 
The ability to read pump curves is essential to long-term pump performance. In new applications, they aid in the selection of a pump that meets performance requirements. In troubleshooting applications, they help engineers and operators evaluate conditions and solve performance problems.
 
A pumps performance will be inline with the pressure losses in the system, with pumps producing a differential flow and pressure based on the conditions at the inlet. A pump curve is a graphical representation of what flows and differential pressures can be produced by a pump.
 
As 90% of problems with pumps are caused by the system they are installed in, it is important to note that pump selection is just part of the process of selecting a pump which is right for the process.

In order for a pump to be selected for your process it is important that the following are known:
  • Fluid being pumped
  • Application
  • Flow Required
  • Pressure required
  • Viscosity of fluid & Specific Gravity
  • Temperature
  • Power available / Power medium being used to drive pump.
Reading a pump performance curve
In the simplest words, pump performance curve is a graph of 'differential head' developed by the pump, plotted against the operating flow rate.

When more fluid is pushed through the pump, it is generally going to develop less differential head (given the mechanical and power constraints)
 
 
 
https://www.youtube.com/watch?v=U8iWNaDuUek 
 
 
 
https://www.csidesigns.com/blog/articles/how-to-read-a-pump-curve