Hale 4DK Series - Manual (Page 46)

46 Manual p/n: 029-0020-79-0
4DK Series Pumps
Stages ................. The number of impellers in a pump that are used in series; that is, one following
another in terms of flow. Each impeller develops part of the total pump pressure.
Tachometer ......... Indicates the speed of the engine crankshaft in revolutions per minute.
Torque ................. The force that acts to produce rotation.
Transfer Valve ..... A two-position valve in a pump that changes the operation from parallel (volume) to
series (pressure) operation and vice versa (not used on single stage pumps).
Vanes .................. Guides inside an impeller that direct fluid to the volute (pump body).
Volute .................. A gradually increasing discharge waterway. Its function is to collect the water from
the impeller and, depending on its design, it either increases pressure and
decreases velocity or increases velocity and decreases pressure.
Water .................. Amount of energy in the water stream.
Horsepower
Wear Rings ......... See Clearance rings.