Centrifugal Pumps - Minimum Flow
Catastrophic failures may occur in centrifugal pumps if the liquid within the pumps starts to vaporize. A minimum flow through the pump must be maintained to prevent flashing within the casings. The heat transferred from the motor must be removed to keep the fluid below its saturation temperature at the actual pressure.
If 15 oF is accepted as a temperature rise in the pump casing - the minimum water flow through the pump can be estimated to
q = PBHP / 2.95 cp SG (1)
where
q = minimum flow rate (gpm)
PBHP = power input (BHP)
cp = specific heat of fluid (Btu/lb oF)
Related Topics
• Pumps
Design of pumping systems and pipelines. With centrifugal pumps, displacement pumps, cavitation, fluid viscosity, head and pressure, power consumption and more.
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