Chapter 9 - Fire Pump Theory Flashcards
What should be worn during operations and where should nonessential personnel and civilians be kept?
A. PPE and a safe distance
B. eye protection and warm
C. PPE and warm
D. eye protection and as close as possible
A. PPE and a safe distance
Drivers should be aware of the _____ involved in pumping operations and the potential for _____ to personnel and _____ to equipment and property should a component fail.
- pressure
- injury
- damage
It is necessary to increase the existing pressure with fire dept. pumpers in order to maintain pressure sufficient for fire fighting operations. Where is an exception?
A. a few well developed municipal water systems
B. some industrial complexes or other specialized locations
C. many small town private water systems
D. a few local privately owned businesses
E. A and B
E. A and B
Early pumps used for fire service were hand-operated _____ pumps.
piston
What kind of pump is described as a handle that was pumped operating a piston in a cylinder, forcing water out of the pump to supply water under pressure? A. rotary pump B. constant flow pump C. piston pump D. on-board pump
C. piston pump
What kind of old pump used a hand crank to rotate a gear, forcing water through the pump and hoses? A. rotary pump B. constant flow pump C. piston pump D. on-board pump
A. rotary pump
Single and double action piston pumps of various diameters and strokes replaced the _____ pump.
rotary
What kind of pumps are self priming, deliver a definite volume of water or air, and exhaust air from the pump and deliver water?
positive displacement pumps
Positive displacement pumps are “______ flow machines” in that they produce the same ____ at a given speed regardless of _________ pressure.
- constant
- flow
- discharge
With each operating cycle of a positive displacement pump, all the air and water are \_\_\_\_\_ \_\_\_ of the pump. A. forced out B. recycled out C. sucked out D. all of the above
A. forced out
In order for modern fire apparatus to use static water sources, they continue to have a form of \_\_\_\_\_\_\_ pressure pump (priming pump) connected to the main fire pump. A. high B. low C. back D. positive
D. positive
Modern fire department pumpers are equipped with \_\_\_\_\_\_\_ pumps as their main pump. A. centrifugal B. positive pressure C. negative pressure D. piston pumps
A. centrifugal
This type of pump does NOT use positive action to force water from the pump but rather it depends on the velocity of the water produced by centrifugal force to provide the pressure needed to achieve proper discharge pressure.
centrifugal pump
Why, even though positive displacement pumps have been replaced by the centrifugal pump as the MAIN pumping unit, do they still serve a vital role on modern apparatus?
A. they remove air trapped in the centrifugal pump and water is forced into the pump with atmospheric pressure
B. ability to pump air and foam
C. used as priming devices to get water into the centrifugal pump during drafting
D. all of the above
D. all of the above
What kind of pump is a piston pump?
positive displacement pump
What kind of pump uses a piston that moves back and forth in a cylinder?
piston pump
The pressure developed by a \_\_\_\_ pump causes intake and discharge valves to operate and causes movement of air, water and foam. A. centrifugal B. rotary C. piston D. none of the above
C. piston
Are piston pumps used as high-capacity pumps?
NO
All though not used as high-capacity pumps, are some piston pumps still in service for high pressure stream fire fighting? YES or NO
YES
These multicylinder, PTO-driven pumps can provide pressures up to 1,000 psi for high-pressure fog lines or to inject foam concentrate into a water line or manifold at a higher pressure than the water pump is creating. A. rotary pump B. centrifugal pump C. gear pump D. piston pump
D. piston pump
What type of pump, from the standpoint of DESIGN, are the most simplest of all fire apparatus pumps? A. rotary pump B. centrifugal pump C. gear pump D. piston pump
A. rotary pump
What kind of pump, in modern apparatus, is confined to small capacity, booster-type pumps, low volume, high-pressure pumps and priming pumps? A. rotary pump B. centrifugal pump C. gear pump D. piston pump
A. rotary pump
Most rotary pumps in use today are either rotary-\_\_\_\_\_\_ or rotary-\_\_\_\_ construction. A. piston, vane B. gear, piston C. gear, vane D. cylinder, vane
C. gear, vane
Rotary pumps are driven by either a small \_\_\_\_\_\_ motor or through a \_\_\_\_\_ that extends from the apparatus drive shaft. A. gas, tube B. gas, clutch C. electric, tube D. electric, clutch
D. electric, clutch
Rotary ____ pumps consist of two gears that rotate in a tightly meshed pattern inside a watertight case.
gear
In a rotary gear pump, the gears are constructed so that they \_\_\_\_\_\_ each other and are in \_\_\_\_\_ proximity to the case. A. contact, close B. overlap, close C. are on top of, far D. contact, far
A. contact, close
The gears of a rotary GEAR pump form ___________ and airtight pockets as they turn from the intake to the outlet.
watertight
In a rotary GEAR pump, as the gear ______ reaches the discharge chamber, the air or water contained in that pocket is forced out of the pump.
tooth
What prevents the water or air that has been discharged from the pump from returning to the intake on a rotary gear pump? A. the gears are spread out enough B. the gears are meshed tightly enough C. the gears open slightly D. the gears slow down to prevent it
B. the gears are meshed tightly enough
What do the size of the pockets in the gears AND the speed of the rotation effect in a rotary gear pump?
A. how fast the water can be pumped
B. if water can return from the discharge
C. the total amount of water that can be pumped
D. where the water will end up
C. the total amount of water that can be pumped
Why is the rotary gear pump a positive displacement pump?
Each pocket in the gears contains a _______ amount of water, which is forced out of the pump ____ time the gears turn with a positive action.
- definite
- each
A rotary gear pump is a positive displacement pump because each pocket in the gears contains a definite amount of water, which is forced out of the pump each time the gears turn with a positive action. If the pump tries to move _____ water than the discharge lines can take away, _______ builds up and a _______ relief devices must be provided to handle the excess.
- more
- pressure
- pressure
If water is laden with sand and debris, just like a piston pump, a rotary gear pump is susceptible to WHAT (besides normal wear and tear)
damage
If water is laden with sand and debris, just like a piston pump, a rotary gear pump is susceptible to damage (besides normal wear and tear). To prevent damage to the casing, most gear pumps feature GEARS made of \_\_\_\_\_\_\_ or other \_\_\_\_ \_\_\_\_\_. A. gold, soft metals B. silver, hard metals C. gold, hard metals D. bronze, soft metals
D. bronze, soft metals
If water is laden with sand and debris, just like a piston pump, a rotary gear pump is susceptible to damage (besides normal wear and tear). To prevent damage to the casing, most gear pumps feature GEARS made of bronze or other soft metal. What kind of metal is used for the pumping case? A. gold B. cast iron C. silver D. bronze
B. cast iron
What is the most common type of pump used to prime a centrifugal fire pump?
rotary vane pump
This pump is constructed with moveable elements that automatically compensate for wear, maintaining a tighter fit with closer clearances as the pump is used. A. rotary vane pump B. centrifugal pump C. gear pump D. piston pump
A. rotary vane pump
In what pump is the rotor mounted off center inside the housing?
rotary VANE pump
Where is the distance greater from the rotor to the housing on a rotary vane pump?
A. greater at the intake than the discharge
B. greater at the discharge than the intake
A. greater at the intake than the discharge
Are the vanes free to move within the slot where they are mounted on a rotary van pump? YES or NO
YES
Where are the vans forced against by centrifugal force as the rotor turns on a rotary vane pump?
housing
What happens to the vanes when their surface becomes worn down due to contact with the casing and causes it to maintain a tight fit?
A. they replace themselves every 3rd use
B. centrifugal force retracts them further
C. centrifugal force extends them further
D. the driver/operator must replace them
C. centrifugal force extends them further
When vanes that come in contact with the casing become worn down, centrifugal force extends them further to maintain a tight fit. This self-adjusting feature makes the rotary vane pump more ________ at pumping AIR than a rotary gear pump.
efficient
As the rotor turns, air is trapped between the rotor and the casing in the pockets formed by adjacent vanes. What type of pump is this describing?
rotary vane pumps
As the rotor turns, air is trapped between the rotor and the casing in the pockets formed by adjacent vanes. As the vanes turn, this pocket becomes smaller, which compresses the air and causes pressure to build up. What type of pump is this describing?
rotary vane pumps
As the vanes progress toward the discharge opening on a rotary vane pump, what happens to the pockets?
become even more smaller
At the discharge of a rotary vane pump, what does the level of pressure become that forces the trapped air out of the pump?
maximized/maximum
How is the air/water prevented from returning to the intake on a rotary vane pump?
A. close spacing of the rotor at the discharge
B. vanes become larger at the discharge
C. vanes slow down closer to the discharge
D. a valve closes behind the van
A. close spacing of the rotor at the discharge
As in the rotary gear pump, in the rotary vane pump, the air being ______ from the intake side reduces pressure, creating a ______. This forces water into the pump by atmospheric pressure until it ____ with water. At this point, the pump is primed and _____ water out of the discharge in the same manner as air was forced out.
- evacuated
- vacuum
- fills
- forces
If not exercised regularly, ROTARY pumps are prone to what?
failure
During routine apparatus checks, what should be done to ROTARY pumps to avoid failure?
operate them
Why is a centrifugal pump classified as a NONpositive displacement pump?
A. pumps a definite amount of water with each revolution
B. does NOT pump a definite amount of water with each revolution
C. it does not use suction
D. none of these
B. does NOT pump a definite amount of water with each revolution
What type of pump imparts velocity to the water and converts it to a pressure within the pump itself?
centrifugal pump
The OPERATION of what pump is based on the principle that a rapidly revolving disk tends to throw water introduced at its center toward the outer edges of the disk?
centrifugal pump
On a centrifugal pump, the \_\_\_\_\_\_ acts as the disk receiving its water through the \_\_\_ in the center. A. propeller, hole B. propeller, eye C. impeller, hole C. impeller, eye
C. impeller, eye
On a centrifugal pump, the impeller acts as the disk receiving its water through the eye in the center. The water is thrown out to the \_\_\_\_\_\_\_\_ around the outside edge of the pump housing. A. propeller B. vanes C. gear D. volute
D. volute
What dictates the amount of pressure that is developed in a centrifugal pump?
speed of the impeller
The speed if the impeller dictates the amount of pressure developed in a centrifugal pump. The _______ the disk turned, the ______ the water is thrown, giving the water more _______.
- faster
- harder
- velocity
On a centrifugal pump, if the water is contained at the edge of the disk, the water at the _____ of the container begins to move __________, toward the path of least _________.
- center
- outward
- resistance
On a centrifugal pump, if the water is contained at the edge of the disk, the water at the center of the container begins to move outward, toward the path of least resistance. The velocity of water is converted to \_\_\_\_\_\_\_ by confining the water within the container. A. pressure B. pounds per square inch C. ice D. A and B
A. pressure
On a centrifugal pump, the _____ to which the water rises, or the extent to which it overcomes the ______ of gravity, is based on the ______ of the impeller’s rotation.
- height
- force
- speed
Based on the manufacturer's recommendations, in order to develop the revolutions per minute required for full use of a centrifugal pump, the transmission must be WHAT? A. placed in park B. placed in the correct gear C. placed in cool environment D. placed in reverse
B. placed in the correct gear
What pump has an impeller assembly with the impeller, shaft and seals?
centrifugal pump
In a centrifugal pump, the impeller transmits energy in the form of WHAT to the water?
velocity
What part of the centrifugal pump houses the impeller assembly, collects the water and confines it in order to convert the velocity to pressure? A. impeller B. shaft C. seals D. pump casing
D. pump casing
What part of the centrifugal pump directs the water to the discharge opening of the pump? A. impeller B. shaft C. seals D. pump casing
D. pump casing
What about the impellers rotation is a ratio based upon the power train configuration on a centrifugal pump? A. the speed B. the distance C. the timing D. the force
A. the speed
Where is water introduced from the intake to on a centrifugal pump?
the eye
The volume capacity of the centrifugal pump is dictated by the size of what? A. impeller B. shaft C. seals D. pump casing
A. impeller
Does a larger impeller have a larger eye, allowing greater flow capacity on a centrifugal pump? YES or NO
YES
As the water comes in contact with the vans of the impeller of a centrifugal pump, it is thrown by centrifugal force to the _________ of the impeller.
outside
What confines the water in its travels to the outside of the impeller in a centrifugal pump? (the \_\_\_\_\_\_\_ of the impeller) A. the shrouds of the impeller B. the sides of the impeller C. the backs of the impeller D. the tips of the impeller
A. the shrouds of the impeller
The water is confined in its travel by the shrouds of the impeller in a centrifugal pump, which \_\_\_\_\_\_\_ the velocity for a given speed of \_\_\_\_\_\_\_\_. A. slows, time B. increases, time C. increases, rotation D. slows, rotation
C. increases, rotation
Is the impeller off set within the casing in a centrifugal pump? YES or NO
YES
The offsetting of the impeller within the casing of a centrifugal pump creates water passage of gradually _________ size as it nears the ________ outlet of the pump.
- increase
- discharge
What is the spiral, divergent chamber of a centrifugal pump in which the velocity energy given to water by the impeller blades is converted into pressure? A. combine B. volute C. chamber D. impeller eye
B. volute
The _________ size of the volute is necessary because the volume of water passing through it _______ as it nears the discharge outlet.
- increasing
- increases
In a centrifugal pump, the gradual increasing in size reduces the v\_\_\_\_\_\_ of the water, enabling the \_\_\_\_\_\_\_ to build up proportionately. A. volume, pressure B. volume, water C. velocity, water D. velocity, pressure
D. velocity, pressure
Three main factors that influence a centrifugal fire pump’s discharge pressure:
- _______ of water being discharged
- _______ at which the impeller is turning
- ________ of water when it enters the pump from a pressurized source (hydrant, relay, etc.)
- amount
- speed
- pressure
There are three main factors that influence a centrifugal fire pump’s discharge pressure:
1. amount of water being discharged. If the discharge outlet is large enough in diameter to allow the water to escape as it is thrown from the ______ and collected in the ______, the pressure buildup will be very small.
- impeller
- volute
There are three main factors that influence a centrifugal fire pump’s discharge pressure:
1. amount of water being discharged. If the discharge outlet is _____, a high pressure buildup will result.
closed
There are three main factors that influence a centrifugal fire pump’s discharge pressure:
1. amount of water being discharged. With all other factors remaining constant, the ______ of output pressure that a pump may develop is _______ dependent on the volume of water it is discharged. Thus the discharge volume affects both the intake and _______ pressures.
- amount
- directly
- discharge
There are three main factors that influence a centrifugal fire pump’s discharge pressure:
2. speed at which the impeller is turning. Greater pressure is developed with increased impeller speed. The increase in pressure is roughly equal to the ______ of the change in impeller speed.
square (#²)
There are three main factors that influence a centrifugal fire pump’s discharge pressure:
2. speed at which the impeller is turning. Greater pressure is developed with increased impeller speed. The increase in pressure is roughly equal to the square of the change in impeller speed. SOOOO….if all other factors are constant, doubling the speed of the impeller will result in how much more pressure?
double = 2², 4 times as much
There are three main factors that influence a centrifugal fire pump’s discharge pressure:
3. pressure of water when it enters the pump from a pressurized source (hydrant, relay, etc.). WILL water flow through a centrifugal pump even if the impellers are not turning? YES or NO
YES
There are three main factors that influence a centrifugal fire pump’s discharge pressure:
3. pressure of water when it enters the pump from a pressurized source (hydrant, relay, etc.). When water is supplied to the eye of the impeller, it moves through the impeller by ________. Any movement of the impeller increases both the _______ and the corresponding _______ buildup of the water in the volute.
- itself
- velocity
- pressure
There are three main factors that influence a centrifugal fire pump’s discharge pressure:
3. pressure of water when it enters the pump from a pressurized source (hydrant, relay, etc.). Because the _______ pressure from hydrants, relays etc. adds directly to the pressure developed by the pump, incoming pressure changes are reflected in the ________ pressure.
- incoming
- discharge
A centrifugal pump IS able to pump air. TRUE or FALSE
FALSE
A centrifugal pump in NOT self-priming. TRUE or FALSE
TRUE
To draft from a static water source and prime a centrifugal pump, an \_\_\_\_\_\_\_ priming pump may be used to remove the air and allow atmospheric pressure to force water into the pump. A. external B. automatic C. air actualizing D. all of the above
A. external
What is typically used to prime a centrifugal pump and used to remove the air and allow atmospheric pressure to force water into the pump.
rotating vane pump
To draft from a static water source and prime a centrifugal pump, the use of a device that employs \_\_\_ from the apparatus braking system to power a \_\_\_\_\_\_\_ device that removes air from the suction side of the pump can be used. A. grease, venturi B. power, venturi C. air, outside D. air, venturi
D. air, venturi
To draft from a static water source and prime a centrifugal pump, use of a \_\_\_\_ valve attached to the suction hose strainer may be involved. A. detachable B. quarter turn C. foot D. back flow
C. foot
What are the 2 basic types of centrifugal pumps in the fire service?
- single stage
- multi stage
There is a phenomenon of ________ due to recirculation in single stage pumps, where excess capacity is not allowed to escape the impeller area.
cavitation
There is a phenomenon of cavitation due to recirculation in single stage pumps, where excess capacity is not allowed to escape the impeller area. This can do what to the pump?
cause damage
What are called single-stage centrifugal pumps? (those constructed with what?)
those constructed with a single impeller
What do single-stage centrifugal pumps have a flow capacity of UP to? A. 2,000 gpm B. 1,250 gpm C. 2,500 gpm D. 2,250 gpm
D. 2,250 gpm
What kind of centrifugal pump may consist of front-mount pumps, power take off, auxiliary engine driven and midship pumps that use a single intake impeller and a simple casing to provide flow capacities of up to 2,250 gpm.
single-stage centrifugal pumps
High-capacity pumps require large _______ with waterways that present a _________ amount of opposition to the movement of water. (single-stage centrifugal pumps)
- impellers
- minimum
Newtons’ Third Law of Physics states that for every action……
there is an equal and opposite reaction
Newtons’ Third Law of Physics states that for every action there is an equal and opposite reaction. The water in motion in the pump creates ______ on the pump, its bearings, and other moving parts as well as the casing mounted to the truck frame.(single-stage centrifugal pump)
stress
What may be used to minimize the lateral thrust of large quantities of water entering the eye of the impeller? (single-stage centrifugal pump) A. a stoppage valve B. double-suction impeller C. two way opening C. smaller eye
B. double-suction impeller
The double-suction impeller, which may be used to minimize the lateral thrust of large quantities of water entering the eye of the impeller, takes water from ____ sides. (single-stage centrifugal pump)
both
The double-suction impeller takes water from both sides. The reaction of each side being equal and opposite cancels out the lateral \_\_\_\_\_\_\_. A. thrust B. movement C. water D. side
A. thrust
The double-suction impeller takes water from both sides. The reaction of each side being equal and opposite cancels out the lateral thrust. it also provides a larger _______ for movement of water through the ________. (single-stage centrifugal pump)
- waterway
- impeller
On a single-stage centrifugal pump, because the impeller turns at a slow rate of speed, the radial thrust is developed as the water is delivered to the discharge outlet. TRUE or FALSE
FALSE - high rate of speed
On what type of pump do the stripping edges in the opposed discharge volutes divert the water into tow streams that are 180° apart.
single-stage centrifugal pump
What in a single-stage centrifugal pump cancels the radial thrust when water is being removed?
A. water traveling in the same direction
B. water traveling around the outside
C. water traveling in opposite directions
D. water traveling backwards
C. water traveling in opposite directions
The design of the single-stage centrifugal pump provides a hydraulically \_\_\_\_\_\_\_\_ pump that reduces stress on the pump and vehicle \_\_\_\_\_, helping lengthen the service life of the pump AND apparatus. A. balanced, chassis B. equipped, engine C. serviced, wheels D. equal, driver
A. balanced, chassis
What kind of pump has an impeller for each stage mounted in a single housing?
multistage centrifugal
On a multistage centrifugal pump, the impellers are usually mounted on a double shaft driven by a double train. TRUE or FALSE
FALSE, singe shaft driven by a single train
On a multistage centrifugal pump, generally the impellers are \_\_\_\_\_\_ and have the same \_\_\_\_\_\_\_. A. identical, size B. identical, markings C. round, size D. identical, capacity
D. identical, capacity
The feature of this pump makes it more EFFICIENT; the capability to connect the stages in series for maximum pressure or in parallel for maximum volume by use of a transfer valve.
multistage centrifugal pump
How does one change a multistage centrifugal pump from connected in a series for maximum pressure to parallel for maximum volume?
transfer valve
When you pump in parallel position on a multistage pump, you are pumping in what?
volume
When you pump in parallel position on a multistage pump, each of the impellers takes water from a source and delivers it to the discharge. TRUE or FALSE
TRUE
When you pump in parallel position on a multistage pump, each of the impellers takes water from a source and delivers it to the discharge. Each of the impellers is capable of delivering its rated pressure while flowing __% of its rated capacity.
50
When you pump in parallel position on a multistage pump, each of the impellers is capable of delivering its rated pressure while flowing 50% of its rated capacity. Therefore, the total amount of water the pump can deliver is equal to the sum of the stages. An example would be if it is rated 1,000 gpm at 150psi, how much would each of the impellers supply to the pump discharge manifold?
500 gpm
When you pump in parallel position on a multistage pump, each of the impellers is capable of delivering its rated pressure while flowing 50% of its rated capacity. Therefore, the total amount of water the pump can deliver is equal to the sum of the stages. at the pump DISCHARGE MANIFOLD, what combines together to create the gpm available at a net pressure that it is supplied?
the two streams from each impeller
What type of pump must a driver know that although the pump receives its maximum flow at lets say, 150 psi, the volume of the pump may increase with the capability of the source.
multistage centrifugal pump
When you pump in series position on a multistage centrifugal pump, you are pumping in what?
pressure
When the transfer valve of a multistage centrifugal pump is set in pressure, where is the water directed from the intake manifold?
into the eye of the first impeller
Depending on the specific pump, on a multistage centrifugal pump in series, the first stage increases pressure and discharges __ to __ % of the volume capacity through the TRANSFER VALVE and into the eye of the second impeller.
50 - 70%
In a multistage centrifugal pump in series, once the second impeller receives the 50-70% volume capacity from the first impeller through the transfer valve, what does it do with the water?
increases the pressure, delivers the water at higher pressures though the discharge port
Setting the transfer valve to series (pressure) greatly increases the pressure, however increasing the pressure has a corresponding WHAT in volume? A. addition to B. loss C. increase D. stoppage
B. loss
In a multistage centrifugal pump in series (pressure), only ___ impellers are delivering the water to the pump discharge port therefore the ________ of water available is limited to the amount that ___ impeller can supply.
- one
- volume
- one
Who has recommendations as to the specific times when the transfer valve for their pumps should be operated in volume of pressure? (multistage centrifugal pump)
manufacturers
The process of switching between pressure and volume is sometimes called? (multistage centrifugal pump in series)
“changeover”
Due to the improved efficiency of modern fire pumps, local \_\_\_\_\_\_\_\_\_\_ should establish \_\_\_\_\_\_\_ for switching between pressure and volume based on the manufacturer's recommendations on specific pumps. A. fire fighters, procedures B. neighborhoods, policies C. jurisdictions, rules D. jurisdictions, policies
D. jurisdictions, policies
What should a driver consult for FLOW RATES at which multistage centrifugal pump in series transfer should occur for their specific rig?
manufacturer’s recommendations
Sudden change in pressure can occur as the water pump changes its direction of flow when doing this on a multistage centrifugal pump in series.
operating the transfer valve
Switching from volume to pressure on a multistage centrifugal pump in series can result in the immediate ________ of the previous discharge pressure.
doubling
Switching from volume to pressure on a multistage centrifugal pump in series can result in the immediate doubling of the previous discharge pressure. This change may result in _____ to the pump and hoseline as well as ____ to firefighters.
- damage
- injury
The maximum net pump discharge pressure at which the _____ valve may be ______ operated varies by _______ recommendations for the correct maximum transfer pressure on a multistage centrifugal pump in series.
- transfer
- manufacturer’s
If you changeover on the fireground, must be carefully WHAT with attack crews so that they will be prepared for a slight interruption during the transfer.
coordinated
If there is any question on what position to operate the multistage centrifugal pump in series, it is best to operate it in this…..
parallel (volume) rather than series (pressure)
If there is any question on what position to operate the multistage centrifugal pump in series, it is best to operate it in parallel (volume). In parallel, the pump will be capable of supplying ___ % of its rated capacity at 150psi at __ feet of lift with __ feet of suction hose while drafting.
- 100%
- 10
- 20
What should a driver do at a scene in order to anticipate the demands that may be placed on the pumper as the operation progresses and to choose if they should be in volume or pressure?
size up
On older multistage centrifugal pump in series, operation of the transfer valve is performed ________.
manually
On older multistage centrifugal pump in series, operation of the transfer valve is performed manually. They featured a safeguard making it physically impossible to accomplish THIS while pumping at high pressures.
transfer from pressure to volume or visa versa
On newer multistage centrifugal pump in series, the transfer valve is ______-operated.
power
How might a power-operated transfer valve on a multistage centrifugal pump in series be activated? (3)
- electricity
- air pressure
- water pressure
Many power-operated transfer valves on multistage centrifugal pump in series operate at pressures AS HIGH AS ___ psi.
200
Many power-operated transfer valves on multistage centrifugal pump in series operate at pressures AS HIGH AS 200psi. _____ to pressures in this range poses threats to personnel and equipment.
exposures
Many power-operated transfer valves on multistage centrifugal pump in series operate at pressures AS HIGH AS 200psi. Exposures to pressures in this range poses threats to personnel and equipment. drivers should use ___ with these controls and be familiar with the manual _____ features should the power equipment fail.
- care
- override
What kinds of valves are ESSENTIAL to the operation of a multistage pump?
clapper
In series, (pressure), should a clapper valve stick open or closed or be hampered by debris, what will happen to the pump?
it will not operate properly
n series, (pressure), should a clapper valve stick open or closed or be hampered by debris, when the transfer valve is operated, water allowed to escape back into the _____ will churn through the pump instead of _____ up pressure.
- intake
- build
What can be checked by removing the strainer from a large intake opening and reaching into the pump with a long wooden dowel or similar type of rod.
operation of the clapper valve
What should a clapper valve do to prove it is operating properly?
swing freely
For high pressure fog operations, some fire pumps have been constructed using up to _ impellers connected in series to develop pressures up to 1,000 psi.
4
For high pressure fog operations, some fire pumps have been constructed using up to 4 impellers connected in series to develop pressures up to ____ psi.
1,000
To increase pressure, another method is to have a _____-stage high pressure centrifugal pump mounted outboard in conjunction with a conventional ___-stage pump with separate drive systems.
- single
- two
To increase pressure, another method is to have a single-stage high pressure centrifugal pump mounted outboard in conjunction with a conventional two-stage pump with separate drive systems. When pressure higher than ___ psi are needed, the separate third stage is engaged.
250
To increase pressure, another method is to have a single-stage high pressure centrifugal pump mounted outboard in conjunction with a conventional two-stage pump with separate drive systems. When pressure higher than 250 psi are needed, the separate third stage is engaged. WHERE might these usually be found? and WHY
cities with large numbers of high rise, to supply sprinklers and standpipes to very high rises
What must pumpers be equipped with if they have both a single-stage high pressure centrifugal pump and a conventional two-stage pump operating at 250 psi or higher? (something rated for these pressures)
hoses and adapters rated for these pressures
Is there any positive mechanical isolation of the discharge area of a pump from the intake in the impeller on a multistage pump?
NO
Since there is no positive mechanical isolation of the discharge area of a pump from the intake in the impeller on a multistage pump, the \_\_\_\_\_\_ of the water moving through the impeller prevents most of the water in the discharge from escaping back into the intake. A. volume B. velocity C. vacuum D. All of the above
B. velocity
In the intake side of the pump at the eye of the impeller, the pressure is much _____ than that of the the pressure in the volute. (multistage pump)
lower
On a multistage pump, a very close tolerance must be maintained between the pump casing and the HUB of the impeller. This opening is usually limited to __ inches or less.
.01
On a multistage pump, a very close tolerance must be maintained between the pump casing and the HUB of the impeller. This opening is usually limited to .01 inches or less. Any increase openings lessens the \_\_\_\_\_\_\_\_\_ of the pump. A. working B. happiness C. effectiveness D. suction
C. effectiveness
As a impeller turns at a speed of nearly 4,000 rpm when the pump approaches its capacity, what can cause wear on the impellers?
sediment and dirt passing through the pump
What acts as an abrasive and wears down metal surfaces as it passes between the impeller and the pump casing?
particles of sand
Particles of sand acts as an abrasive and wears down metal surfaces as it passes between the impeller and the pump casing. As ___ increase, greater amounts of water are allowed to slip back into the _____ and are not available at the ______.
- gaps
- intake
- discharge
A gaps increase due to wear from dirt, debris and sand, greater amounts of water are allowed to slip back into the intake and are not available at the discharge. Eventually the pump is no longer able to pump at its rated...... A. RPMs B. discharge C. needs D. capacity
D. capacity
How might one might know or find indications of wear on a multistage pump due to sand, dirt and debris? (when increased engine rpm is required to pump at the rated capacity)
pump testing
What might be used to restore pumping capacities without replacing the entire pump?
wear rings
What is another name for wear rings?
clearance rings
What in the pump casing may be replaced to maintain the preferred spacing between the hub of the impeller and the pump casing? (multistage pump)
wear rings or clearance rings
If the hub of the impeller is also worn down, IS it possible to replace wear rings to maintain proper clearance? YES or NO
YES
Unlike positive displacement pumps, no harm will result from shutting off all the pump discharges for short periods of time in a centrifugal pump. TRUE or FALSE
TRUE
When discharges are closed on a centrifugal pump, the \_\_\_\_ being supplied to the impeller is \_\_\_\_\_ in the form of heat as water within the pump is allowed to churn. A. energy, created B. water, created C. energy, dissipated D. water, dissipated
C. energy, dissipated
When discharges are closed on a centrifugal pump, the energy being supplied to the impeller is dissipated in the form of heat as water within the pump is allowed to churn. If allowed to do this for a long period, the water pump may become quite ___ and the metal parts of the pump may expand.
hot
If the metal parts of a centrifugal pump become too hot, the wear rings and impellers might expand too much and do what to each other? (2) What might it do to the pump? In extreme cases? (what might the wear rings do/what might the pump do)
- rub together and create more heat
- seriously damage
- wear rings may seize = serious pump damage
What type of centrifugal pumps may be equipped with a thermal relief valve that opens to allow overheated water to circulate between the pump and the main water tank or into the atmosphere?
newer models
If you are operating a pump WITHOUT a thermal relief valve, the best course of action to prevent overheating is to ensure that some water is….
A. added to the tank
B. taken out of the tank 10 gallons at a time
C. purged from the system
D. moving through the pump at all times
D. moving through the pump at all times
What can a driver place his hand on to check for excessive pump temperatures?
direct pump intake pipe
If the direct pump intake pipe is warm to the touch, what should a driver open? (3)
- discharge
- tank fill
- circulation valve
In order to prevent overheating, if the driver believes that there will not be anything discharged for an extended time, what should they do?
throttle down to idle and disengage
What transfers the required energy to spin the impellers at a very high rate of speed on?
transmission
Where are pump impellers fastened to?
the shaft
The pump impellers are fastened to the shaft that connects to the _______ case.
transfer
At the point where the shaft passes through the pump casing, a semi-_____ seal must be maintained to prevent ___ leaks that may interfere with the ability to draft.
- tight
- air
At the point where the shaft passes through the pump casing, a semi-tight seal must be maintained to prevent air leaks that may interfere with the ability to draft. \_\_\_\_\_\_\_\_\_ seals are the most common type in use today. A. mechanical B. super C. rubber D. iron
A. mechanical
What kind of seals form a tight seal without dripping and do not require a periodic adjustment? (at the point where the shaft passes through the casing)
mechanical seals
Mechanical seals seals form a tight seal without dripping and do not require a periodic adjustment. However, to lubricate the seals, what should be done?
operate pump regularly
Mechanical seals should not be allowed to WHAT in cold weather?
freeze
If mechanical seals freeze in cold weather, damage may incur and it might require the _______ of the entire pump and drive assembly in order to replace the ____.
- disassembly
- seals
What will cause mechanical seals to overheat and become damaged?
running them waterless
This is composed of rope fibers impregnated with graphite or lead (most common type of.....) A. pump B. rope C. seal packing material D. engine belt
C. seal packing material
The most common type of seal packing material is composed of rope fibers impregnated with graphite or lead. This material is pushed into a stuffing \_\_\_\_ by a packing \_\_\_\_\_ driven by a packing adjustment mechanism. A. box, gland B. cartridge, gland C. box, finger D. container, machine
A. box, gland
Are some centrifugal fire pumps equipped with ceramic or mechanical seals that are not adjustable? YES or NO
YES
Where are packing rings primarily used in?
older fire pumps
When packing rings wear with the operation of the shaft, the packing gland can be ______ in order to control any _____ and allow the pump to draft.
- tightened
- leaks
When packing rings come into contact with the shaft, what is developed?
heat
When packing rings come into contact with the shaft, heat is developed. In order to overcome this, a _____, known as a lantern or slinger ring, is supplied with the packing to provide coooling.
spacer
What is also known as a lantern or slinger ring?
spacer
What does a spacer/lantern/slinger ring allow around the packing and prevents the buildup of excessive amounts of heat that may score the shaft?
small amount of water to leak out
If packing is too loose around a packing ring, an excessive amount of WHAT may leak from the pump during operations? What else might the rig not be able to do?
- water
- draft from static source
How must packing be adjusted? According to whom?
manufacturer’s recommendations
Generally when a pump is operating under pressure, water _____ drip at a rate specified by the pump _______ from the packing glands, but not run as a steady ______.
- should
- manufacturer
- stream
The packing around packing rings only receives water for lubrication if the pump is empty and not operating. TRUE or FALSE
False, only when pump is full and operating under pressure
Most manufacturers recommend the pump to be \_\_\_\_\_ between fire calls, especially in cold weather conditions. A. filled B. cooled off C. topped off D. drained
D. drained
What might cause excessive leaking from a pump if not used for extended periods of time?
the packing drying out
After a period of dryness, adjustment to the packing should be made only after the pump has operated under pressure and the packing has a chance to do this.... A. move around B. get wet C. seal properly D. get worn
C. seal properly
If the pump is operated dry for any length of time, damage to the _____ may result. Any weakening may cause failure during future use.
shaft
What type of seal available on certain pumps are made of a material that offers superior resistance to warping , stretching and corrosion?
ceramic
When deciding what should fire department factor the intended use of the pump and its cost, appearance, space requirements and ease of maintenance?
what pump drive system will work best
Pumps powered by gasoline or diesel engines independent of the vehicle-drive engine are examples of \_\_\_\_\_\_\_\_\_ pumps. A. PTO B. Auxiliary C. Mid-ship D. front-mount
B. Auxiliary
Some auxiliary pumps may be powered by special fuels such as jet fuel for military or other special applications. TRUE or FALSE
TRUE
Sometimes used on structural rigs, auxiliary engine driven pumps most common applications are:
- ______ rescue fire fighting (ARFF)
- ______ water supply
- trailer _______ fire pumps
- portable ____ pumps
- airport
- wildland
- mounted
- fire
What kind of engine drive pump may be part of a skid-mount assembly that includes a small water tank, booster reel and small diameter attack lines?
auxiliary engine drive pump
What is the general pumping capacity of a auxiliary engine drive pump? _____ gpm
500
Where might a auxiliary engine drive pump be mounted in some jurisdictions?
pickup truck
What kind of fire pumps are most common to initial attack, wildland, or mobile water supply applications (engine driven pump)
power take-off drive (PTO)
In a power take-off drive, the pump is driven by a \_\_\_\_\_\_\_\_ connected to the PTO. A. cylinder B. driveshaft C. finger D. watertank
B. driveshaft
In recent years, what kind of drive system is being used in structural apparatus pumpers?
PTO drive
What is the PTO typically attached to if on a pumper?
transmission
Some manufacturers offer a \_\_\_\_-engine PTO system that is driven off the engine's \_\_\_\_\_. A. front, shaft B. rear, shaft C. side, flywheel D. rear, flywheel
D. rear, flywheel
Some manufacturers offer a rear-engine PTO system that is driven off the engine’s flywheel. This type of system has been used with much success in the construction and refuse industries for many years. TRUE or FALSE
TRUE
Some manufacturers offer a rear-engine PTO system that is driven off the engine’s flywheel. What ability is given with this type of mounting?
pump and roll
What type of mounting of the engine pump offers opportunity for shorter wheelbase, additional room for compartments as well as crosslays and that are packed lower on the apparatus body where they are more accessible? A. front-engine PTO system B. rear-engine PTO system C. back-mounted PTO system D. side-mounted PTO system
B. rear-engine PTO system
Proper mounting of a PTO drive is essential for dependable and smooth operations. The gear case must be mounted in a location that allows for a minimum of \_\_\_\_\_\_ in the driveshaft. A. turns B. openings C. angles D. curves
C. angles
The gear case of the PTO drive for fire pumps must be mounted in a location that allows for a minimum of angles in the driveshaft as well as it must not extend too far below the \_\_\_\_\_\_\_ or it may be damaged during driving. A. chassis B. gears C. brakes D. body
A. chassis
What is powered by an idler gear in the vehicle’s transmission?
PTO drive (fire pumps)
The speed of the shaft in a PTO drive for fire apparatus is independent of the gear in which the road transmission is operating when the pump is in use BUT is under the control of the WHAT?
clutch
The speed of the shaft in a PTO drive for fire apparatus is independent of the gear in which the road transmission is operating when the pump is in use BUT is under the control of the clutch. When the clutch is disengaged to stop or change gears, what happens to the pump?
stops turning
The PTO pump does permit pump and roll operations, but is not as effective as the separate \_\_\_\_\_\_ unit. A. pump B. transmission C. apparatus D. engine
D. engine
On a PTO drive for fire apparatus, the WHAT of the engine determines the pressure developed, therefore will determine the pressure of the water pump while driving?
speed
Where should you mount a pressure gauge if a vehicle is being used for pump and roll operations?
inside the vehicle
When hoselines are being used during pump and roll operations, which should you use to drive the vehicle?
speedometer or pressure gauge?
pressure gauge
During pump and roll operations, what gear makes maintaining the balance between speed and pressure easiest?
lowest gear
In the past, how much were PTO drive pumps limited to in GPM?
500 gpm
Today, some manufacturers provide full torque power-take offs for pumping that allows for a pump as large as ______ gpm.
1,250 gpm
Today, some manufacturers provide full torque power-take offs for pumping that allows for a pump as large as 1,250 gpm. This is commonly used with \_\_\_\_\_\_\_\_\_ transmissions where the \_\_\_\_\_\_ of the engine drives the PTO unit. A. manual, flywheel B. automatic, shaft C. automatic, flywheel D. manual, shaft
C. automatic, flywheel
Today, some manufacturers provide full torque power-take offs for pumping that allows for a pump as large as 1,250 gpm. They must be equipped with properly rated ______, _____ shafts and PTO systems in order to provide the necessary _______ to operate the pump at capacity.
- engine
- drive
- power
________ requirements of the vehicle must include accessories such as warning lights, air compressor, and the vehicle’s air conditioning system, that may be operated during pumping. (Due to high power needs of an engine running at 1,250 gpm)
horsepower
A front-mounted pump features an _____ front bumper with a pump mounted _______ the bumper and the grill of the vehicle.
- extended
- between
What type of pump is typically driven through a gear box and a clutch connected by a drive shaft to the front of the crankshaft? A. midship B. high idle C. front-mount D. rear-mount
C. front-mount
The front-mount pump is typically driven through a gear box and a clutch connected by a drive shaft to the front of the crankshaft. The gear box uses a STEP UP GEAR RATIO, which causes the impeller of the pump to turn ______ than the engine.
faster
The front-mount pump is typically driven through a gear box and a clutch connected by a drive shaft to the front of the crankshaft. The gear box uses a STEP UP GEAR RATIO, which causes the impeller of the pump to turn faster than the engine. This ratio is set to _____ the torque of the engine to the rotation speed required for the impeller to deliver the pump’s rated capacity.
match
The maximum capacity of the front-mounted pump depends on the limitations of the WHAT?
engine driving it
The maximum capacity of the front-mounted pump depends on the limitations of the engine driving it, typically up to _____ gpm.
1,250
