09 - IFSTA Chapter 09 Flashcards
In a midship mounted pump, the gear ratio is arranged so that the impeller turns faster than the engine, at what ratio?
1.5 to 2.5
With the engine idling and the pump engaged, most speedometers will indicate what miles per hour?
10 to 15 mph
(0 mph for some engines, including all engines w/ a PTO pump)
The piping system and the fire pump itself must be capable of withstanding a hydrostatic test of how much psi?
500
According to NFPA 1901, all fire apparatus must be equipped with at least two, 2.5” discharges based on the pumps rating of how many gallons per minute?
750
NFPA 1901 requires all intakes or discharges be equipped with a slow acting valve control with what diameter valve?
3” or greater
It is generally recommended that the intake relief valves be set to open when the intake pressure rises how many PSI above the necessary opering pressure?
10
A pump that consists of two gears that rotate in a tightly meshed pattern inside a watertight case is referred to as?
Rotary gear
What type of pumps are constructed with moveable elements that automatically compensate for wear, maintining a tighter fit with closer clearances as the pump is used?
Rotary vane
The ____ acts as the disk receiving its water through the eye in its center.
imepller
The volume capacity of the pump is dictated by the size of what?
Impeller
When each of the impellers takes water from a source and delivers it to the discharge, you are operating the transfer valve in what position?
Parallel
When all of the water from the intake manifold is directed into the eye of the first imepeller, you would have the transfer valve in what position?
Series
What valves are essential to the operation of a multi two stage pump?
Clapper
Due to its self adjusting feature, rotary _____ pumps are more efficient at pumping air than rotary _______.
vane; gear
Which pump does not pump a definite amount of water with each rotation?
Centrifugal
What form of energy is transmitted to the water by the impeller?
Velocity
The engine’s piping typically tapers to a square shape when entering the pump in order to eliminate what?
Vortex
What feature is designed to regulate the engine speed to match the pump discharge requirements?
Pressure Governor
The electronic governor returns the engine to idle when the intake pressure drops below what PSI?
30
The pressure control device must restrict the pressure from exceeding what PSI above the set level?
30
What does changeover mean?
swithcing between pressure and volume
When can you double your discharge pressure in a multistage centrifugal pump?
Changing from volume to pressure
What are the main pumps on new fire engines?
Centrifugal pumps
Name 2 types of postive displacement pumps.
rotary vane and rotary gear