Chapter 9 Flashcards
Provides a reading of residual pressure when the pump is operating from a hydrant or is receiving water through a supply line from another pumper
Master intake gauge
For a multistage centrifugal fire pump, switching from volume to pressure
can result in immediate doubling of previous discharge pressure.
Statements about a centrifugal pump
A centrifugal pump is unable to pump air and is not self priming
According to NFPA® 1901, pumpers with a capacity greater than 500 gpm (2 000 L/min) should be able to flow
at least 500 gpm
Statements about positive displacement pumps
hey serve a vital role on modern apparatus because of their ability to pump air and foam
Indicates the status of the vehicle’s alternator?
Ammeter
What is the purpose of slow-acting valve controls
Minimize risk of damage caused by water hammer when large volumes of water are being moved
Category of primer includes both the rotary vane primer and the rotary gear primer?
Positive displacement primers
Which part of a centrifugal pump transmits energy in the form of velocity to the water
Impeller
Type of pump consists of two gears that rotate in a tightly meshed pattern inside a watertight case
Rotary gear pump
Any significant deviation from normal oil pressure reading is MOST likely to indicate
an equipment malfunction
The simple devices that make use of the vacuum already present in the intake manifold of any gasoline-driven engine
Vacuum primers
When referring to pump wear rings and packing, why must very close tolerances be maintained between pump casing and the hub of the impeller
Any increase in opening lessens the effectiveness of the pump
Which pump design offers advantages such as more even weight distribution on the chassis and more usable compartment space
Front-mount pump
The most common type of valve and permits the full flow of water through a line with a minimum friction loss
Ball-type valve
The ability to initiate a successful drafting operation depends on creating
a lower pressure within the pump and intake hose than exists in the atmosphere
When pressure drops below a specified setting, the electronic pressure governor will:
return the engine to idle speed
In a centrifugal pump, the speed of the impeller dictates the amount of pressure developed and the faster the disk is turned
the harder water is thrown, giving the water more velocity
Main factor that influences a centrifugal fire pump’s discharge pressure?
Pressure of water when it enters pump from a pressurized source
Most manufacturers recommend that the centrifugal fire pump be drained
between fire calls.
Which pump may be offered by some manufacturers in a rear-engine design driven off the engine’s flywheel
Power-take-off (PTO) drive
Is used to operate the priming device when the pump will draft from a static water supply?
Primer control
type of positive displacement pump operates using a piston that moves back and forth in a cylinder?
Piston pump
In a modern apparatus, rotary pumps would MOST likely be used as which of the following types of pumps
As low volume, high-pressure pumps
Uses a compressor to supply an airline to a jet pump creating a Venturi Effect that primes the pump using no moving parts or lubricants
Air primers
In a centrifugal pump, with all other factors remaining constant, doubling the speed of the impeller will result in:
4 x times more pressure
When pumping in the parallel (volume) position:
each of the impellers takes water from a source and delivers it to the discharge.