Centrifugal pumps and minimum continuous flow to prevent flashing
Catastrophic failures may occur in centrifugal pumps if the liquid within the pumps starts to vaporize.
To prevent flashing within the casings - a minimum flow must always be maintained. Transferred heat from motors must be removed to keep the fluids below saturation temperature.
If a temperature rise of 15 oF is accepted in a casing - the minimum water flow through a pump can be estimated to
q = PBHP / 2.95 cp SG (1)
q = minimum flow rate (gpm)
PBHP = power input (BHP)
cp = specific heat capacity (Btu/lb oF)
SG = specific gravity of the fluid