7
PIPING DIAGRAM
Properly sized pressure gauges should be installed in both the inlet and
discharge lines. The gauges will allow the operator to easily observe the inlet
and discharge pressures of the pump and thereby determine if the pump is
operating according to the performance curve. If cavitation, vapor binding or
other unstable operation should occur, a widely fluctuating discharge pressure
will be noted.
If there is any possibility of high pressure remaining on the outlet of the pump
after the pump has been shut down (as with two or more pumps operating in
parallel or when pumping to a high pressure reservoir), a check valve must be
added to the discharge side of the pump and a pressure relief valve, set at 225
psi (15.5 bar) or less, must be installed in the inlet piping between the pump
and the intake shut-off valve. This will prevent damage to the mechanical seal
and the inlet piping.
