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SUCTION SPECIFICATIONS
LIQUID TEMPERATURE AND OVERHEATING
The maximum liquid temperature for this pump is 160ºF (71ºC). Do not apply it at a higher operating temperature.
Overheating can occur if the pump is operated with the valves in the suction and/or discharge lines closed. Operating
against closed valves could bring the liquid to a boil, build pressure, and cause the pump to rupture or explode. If
overheating occurs, stop the pump and allow it to cool before servicing it. Refill the pump casing with cool liquid. As
a safeguard against rupture or explosion due to heat, this pump is equipped with a pressure relief valve that will
open if vapor pressure within the pump casing reaches a critical point. If overheating does occur, stop the pump
immediately and allow it to cool before servicing it.
APPROACH ANY OVERHEATED PUMP CAUTIOUSLY
. It is
recommended that the pressure relief valve assembly be replaced at each overhaul, or any time the pump casing
overheats and activates the valve.
PUMP VACUUM CHECK
With the pump inoperative, install a vacuum gauge in the system. Make sure the pump is at least half filled with
liquid. Block the suction line and start the pump. At operating speed, the pump should pull a vacuum of 20 in of
mercury (67728 Pa) or more. If it does not, check for air leaks at the suction piping gaskets.
BEARING TEMPERATURE CHECK
Bearings normally run at higher than ambient temperatures because of heat generated by friction. Temperatures up
to 160ºF (71ºC) are considered normal for bearings and they can operate safely to at least 180ºF (82ºC). Measure
the bearing temperature with a contact-type thermometer.
A
C
B
A = Suction Lift: The distance between the centerline of
the pump impeller and the surface of the liquid being pumped.
B = Vertical Discharge Head: Vertical distance from the centerline of
the pump inlet to the centerline of the highest point of discharge.
C = Total Dynamic Head (TDH): Suction lift plus vertical discharge
plus friction loss.
Note:
To calculate PSI, divide TDH in feet by 2.31.
TDH (35 ft.)
2.31
Example:
= 15.15 PSI