Hale MG User Manual
Page 149

Glossary
G - 1
Atmospheric
Pressure caused by the elevation of air above the earth.
Pressure
Auxiliary
Permits water from a pump to cool the radiator water through a heat exchange.
Cooling Valve
Capacity
Pump flow rating.
Cavitation
Caused by the pump attempting to deliver more water than is being supplied. This causes the
formation of water vapor, and liquid water, under pressure, rushes in to fill the empty space.
This damages the pump.
Centrifugal
Force that tends to make rotating bodies move away from the center of rotation.
Force
Centrifugal
A pump that uses a rapidly spinning disk to create the pressure for water movement.
Pump
Certification
Pumper test in accordance with NFPA standards to determine if a pump can deliver its rated
volume and pressure.
Check valve
In two stage pumps, there are two swing check or flap valves in the suction passage of the
second stage. They are located in each side of the pump between the suction tube and the
pump body. These valves swing open when pumping in parallel for volume. They are
closed by first stage pressure when pumping in series for pressure.
Clearance
Prevent discharge water from returning to the eye of the impeller.
Rings
Compound
A compound gauge is graduated to read pressure in pounds per square inch and vacuum in
Gauge
inches of mercury.
Double
Water enters on both sides of the impeller.
Suction
Impeller
Dry prime
Provides information on the ability of a pump to evacuate air and draft water.
Test
Eye, Impeller Point where water enters the impeller.
Flow Meter
Measures the volume of water flowing.
Friction
Loss of pressure in hose, fittings, standpipes, and other appliances because of the
Loss
resistance between the water molecules and the inside surfaces of hoses, fittings,
standpipes, and other appliances.
Front-mount
Pump mounted ahead of the engine.
Pump