OM-06575
PA SERIES
OPERATION
PAGE C - 2
Liquid Temperature And Overheating
The
maximum
liquid temperature for this pump is
160
F (71
C). Do not apply it at a higher operating
temperature.
Overheating can occur if operated with the valves
in the suction or discharge lines closed. Operating
against closed valves could bring the liquid to a
boil, build pressure, and cause the pump to rup
ture or explode. If overheating occurs, stop the
pump immediately and allow it to completely cool
before servicing it.
Approach any over‐heated
pump cautiously
.
Allow an over‐heated pump to com
pletely cool before servicing. Do not re
move plates, covers, gauges, or fittings
from an overheated pump. Liquid within
the pump can reach boiling tempera
tures, and vapor pressure within the
pump can cause parts being disen
gaged to be ejected with great force. Af
ter the pump cools, drain the liquid from
the pump by removing the casing drain
plug. Use caution when removing the
plug to prevent injury to personnel from
hot liquid.
As a safeguard against rupture or explosion due to
heat, this pump is equipped with a pressure relief
valve which will open if vapor pressure within the
pump casing reaches a critical point. If over‐heat
ing does occur, stop the pump immediately and al
low it to cool before servicing it.
Approach any
over‐heated pump cautiously
. It is recom
mended that the pressure relief valve assembly be
replaced at each overhaul, or any time the pump
casing over‐heats and activates the valve.
Never
replace this valve with a substitute which has not
been specified or provided by the Gorman‐Rupp
Company.
Strainer Check
Check the strainer regularly, and clean it as neces
sary. The strainer should also be checked if pump
flow rate begins to drop. Monitor and record the
vacuum suction gauge readings regularly to detect
strainer blockage.
Never
introduce air or steam pressure into the
pump casing or piping to remove a blockage. This
could result in personal injury or damage to the
equipment. If backflushing is absolutely neces
sary,
liquid pressure
must be limited to 50% of the
maximum permissible operating pressure shown
on the pump performance curve.
STOPPING
Never halt the flow of liquid suddenly. If the liquid
being pumped is stopped abruptly, damaging
shock waves can be transmitted to the pump and
piping system. Close all connecting valves slowly.
If the application involves a high discharge
head, gradually close the discharge
throttling valve before stopping the pump.
After stopping the pump, lock out or disconnect
the power source to ensure that the pump will re
main inoperative.
BEARING TEMPERATURE CHECK
Bearings normally run at higher than ambient tem
peratures because of heat generated by friction.
Temperatures up to 160
F (71
C) are considered
normal for bearings, and they can operate safely to
at least 180
F (82
C).
Checking bearing temperatures by hand is inaccu
rate. Bearing temperatures can be measured ac
curately by placing a contact‐type thermometer
against the housing. Record this temperature for
future reference.
A sudden increase in bearing temperatures is a
warning that the bearings are at the point of failing
to operate properly. Make certain that the bearing
lubricant is of the proper viscosity and at the cor
rect level (see
LUBRICATION
in the Maintenance
and Repair Manual). Bearing overheating can also
be caused by shaft misalignment and/or excessive
vibration.
