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73 Cards in this Set

  • Front
  • Back
Name 2 problems associated with Piston Pumps.
Pulsating Fire Stream & Susceptible to Wear
Output capacity of PDP (Rotary Gear) depends on _____ & _____.
Size of Pockets & Speed of Rotation
What are the Gears of a PDP (Rotary Gear) made of?
Soft Metal such as Bronze
What is the Casing of a PDP (Rotary Gear) made of?
Strong Alloy such as Cast Iron
In Volume (Parallel) each impeller delivers its rated pressure while flowing ____ % of its rated capacity.
In Pressure (Series) ____% of volume capacity is discharged into the eye of the second impeller.
What is the maximum discharge pressure allowed when changing over?
What type of valve dictates volume versus pressure?
What is the first sign of wear between the Hub of Impeller & Casing (Wear Rings)?
Greater RPM required to pump Rated Capacity.
Define Latern Ring.
Spacer between Packing designed to cool & lubricate Packing.
How many 2 1/2 inch or larger Discharges are required on a Pumper?
Enough to flow its Rated Capacity
What is the minimum # of 2 1/2 inch Discharges on a Pumper with a Rated Capacity of 750 GPM or greater?
At least 2.
What is the minimum # of 2 1/2 inch Discharges on a Pumper with a Rated Capacity less than 750 GPM?
What is the largest Discharge allowed on a Pump Panel?
2 1/2 inch
1 1/2, 1 3/4, 2 inch Preconnect Discharges must be supplied by at least ____ inch pipe.
2 inch
What type of valve are Discharges usually equipped with?
Locking Ball Valve
A Tank less than 1000 Gallons must have a Tank Fill Line at least ____ inches?
1 inch
A 1000 Gallon Tank or greater must have a Tank Fill Line at least ____ inches?
2 inches
Which side of the pump is the Circulator Valve connected to?
Discharge Side
What is the most common type of Pump Valve? Why?
Ball Valve; Permits full flow with minimum Friction Loss
What is the purpose of Automatic Pressure Regulation?
Ensure safety of FF operating hoseline.
____ actuates the Relief Valve to bypass water from the ____ to the ____.
Spring Loaded Pilot Valve; Discharge Side; Intake Chamber.
Define PTO in regards to fire pumps.
Power Take Off; Pump driven by rotating shaft that transfers power from vehicle's engine.
Define Priming.
Removing all or most of the air from pump thus lowering Atmospheric Pressue within the Pump Casing.
What are the 2 general categories of Fire Pumps?
Positve Displacement & Centrifugal
Explain the Positive Displacement Pump.
Self priming pump that moves a given amount of water through the pump chamber with each stroke; All water & air is forced out of pump with each operating cycle; Used to prime Centrifugal Pump
Explain the Centrifugal Pump.
Pump with one or more Impellers that utilized centrifugal force to provide discharge pressure; Take advantage of Incoming Pressure
What are 2 types of Positive Displacement Pumps?
Piston & Rotary
The Volume Capability of Centrifugal Pump depends on ___.
Size of the Eye
What are the 2 main parts of a Centrifugal Pump?
Impeller & Casing
Define Impeller.
Vaned, circulating part of Centrifugal Pump that transmits motion (velocity) to water.
Define Casing.
Collects & confines water to convert velocity to pressure.
Define Volute.
Spiral, divergent chamber of Centrifugal Pump in which velocity from the Impeller is converted to pressure.
As the Volute nears the Discharge Side its size ___.
What are the 3 main factors influencing Centrifugal Pump Discharge Pressure?
1. Amount of water being discharged; 2. Speed of Impeller; 3. Intake Pressure
What are the 2 basic types of Centrifugal Pumps?
Single Stage (1 Impeller) & Dual Stage (2 Impellers)
What is the benefit of a Double Suction Impeller?
Takes in water from both sides to minimize Lateral Thrust.
At what PSI does the pump receive Maximum Flow Rating?
150 PSI
What are Packing Rings used for?
Maintain semi-tight seal where the shaft passes through Pump Casing.
What are Packing Rings made of?
Rope Fibers impregnated with Graphite or Lead
What are 2 types of Ball Valve Actuators?
T-Handles & Quarter Turn
At what RPM does a Centrifugal Pump rotate?
2000 - 4000 RPM
How many times faster does the Impeller turn than the Engine?
1.5 - 2.5
What are 3 categories of Primers?
Positive Displacement; Exhaust; Vacuum
Describe a T-Handle Actuator.
Pulls straight out & locks via 90 degree twist; Sliding gear tooth rack engages gear on valve stem.
What are the advantages of T-Handles?
Provide Mechanical Advantage; Easy to operate under pressure; Allow more precise setting.
Within how many seconds must a Pressure Control Device activate?
3 - 10 seconds
How many PSI above a discharge setting must a Pressure Control Device activate?
At least 30 PSI
What are the 2 main functions of a Relief Valve?
Be sensitive to pressure changes & be able to relieve excessive pressure within the Pump Discharge.
How does a Pressure Governor work?
Regulates power output of engine to match Pump Discharge requirments; Engine Speed dictates Impeller Speed & Impeller Speed dictates Pressure
What are 2 advantages of an Electric Primer versus a Mechanical Primer?
Operates regardless of engine speed & allow maximum flexibility in mounting.
What are 2 purposes of Primer Oil?
Seals gap between Gears & Casing as pump wears (provding better efficeincy) & Protects metal from corosion.
What is the purpose of the vent in the Oil/Fluid Line?
Prevents Oil/Fluid from being siphoned out of tank after Primer use.
What results if Packing is too tight?
Water will not flow between Packing & Shaft causing heat to build up.
What results if Packing is too loose?
Excessive leak of air & water will affect pumps ability to draft.
When does Packing actually receive water for lubrication?
When the pump is full & operating under pressure
What are 2 types of Pump Drive Systems?
Auxillary Engine Driven & Power Take Off
What are 3 types of Pump mounting arrangements?
Front Mount; Midship Transfer; Rear Mount
Define Auxillary Engine Drive Pump.
Pump powered by engine independent of vehicle's engine.
What is the benefit of an Auxillary Engine Drive Pump?
Capable of Pump & Roll
Where is a Midship Transfer Drive Pump mounted?
Laterally across frame behind engine
How is the Midship Transfer Drive Pump powered?
Powered by split shaft gear (Transfer Case) in drive line between transmission & rear axle; Driven by series of gears or drive chain.
What 2 things limit the Maximum Capacity of Midship Transfer Drive Pumps?
Engine Horsepower & Size of Pump
What are 4 types of Midship Transfer Case controls?
Mechanical; Electrical; Hydraulic; Pneumatic
What are the 4 primary components of Pump Piping System?
Intake Piping; Discharge Piping; Pump Drains; Valves
During Hydrostatic Testing, how many PSI must the pump & piping system be able to withstand
500 PSI
How many GPM must a pumper with a capacity of 500 GPM or less be capable of flowing from the tank?
250 GPM
How many GPM must a pumper with a capacity of more than 500 GPM be capable of flowing from the tank?
500 GPM
What prevents damage to the tank if the Tank-to-Pump Valve is open when water is being supplied under pressure?
Check Valves
Where is the Primer tapped into the Pump?
At the high point on the Intake Side of Impeller Eye
Where are Intake lines tapped into Pump? Which Intake line is an exception?
Below the Impeller Eye; Tank-to-Pump Line which provides water under natural pressure of gravity.
Why does Intake Piping taper to a square as it nears the pump?
To eliminate vortex that could allow air to enter the pump.
What 2 things determine the amount of flow that can be obtained through Intake piping?
Diameter of pipe from valve to pump inlet & Straightness of pipe routing.