Liquid Fuels Systems-cdc3e452 (Vol.4)
Liquid Fuels Maintenance Journeyman
CDC 3E451
Volume 4: Operation and Maintenance of Mechanical System Components
Questions and Answers
- 1.
(601) How many basic designs of gate valves are there?
- A.
1
- B.
2
- C.
3
- D.
4
Correct Answer
B. 2Explanation
rising stem and non-rising stemRate this question:
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- 2.
(602) How often do you inspect a gate valve for leaks?
- A.
Weekly
- B.
Monthly
- C.
As required
- D.
Not required
Correct Answer
C. As requiredExplanation
The frequency of inspecting a gate valve for leaks depends on its condition and usage. If there are signs of leaks or if the valve is frequently used, it should be inspected more often, possibly on a weekly or monthly basis. However, if the valve is rarely used and there are no visible signs of leaks, it may not require regular inspections and can be inspected as required. The answer "As required" indicates that the inspection frequency should be determined based on the specific circumstances of the gate valve.Rate this question:
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- 3.
(601) During repacking, a gate valve should be placed in what position?
- A.
Open
- B.
Closed
- C.
Either open or closed
- D.
Intermediate between open and closed
Correct Answer
B. ClosedExplanation
During repacking, a gate valve should be placed in the closed position. This is because repacking involves replacing the packing material around the valve stem to prevent leakage. By closing the valve, it ensures that the flow of fluid is completely stopped, allowing for safe and effective repacking without any risk of leaks or accidents. Placing the valve in any other position, such as open or intermediate, would not provide the necessary safety and stability required for the repacking process.Rate this question:
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- 4.
(601) For large gate valves, what type of packing is best?
- A.
Nylon
- B.
Teflon
- C.
Graphite
- D.
Multi-layered cardboard
Correct Answer
B. TeflonExplanation
Teflon is the best type of packing for large gate valves. Teflon is known for its excellent chemical resistance, low friction, and high temperature resistance. These properties make it ideal for use in valves where it can provide a tight seal, prevent leaks, and withstand harsh operating conditions. Nylon, graphite, and multi-layered cardboard do not possess the same level of durability and resistance as Teflon, making them less suitable for this application.Rate this question:
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- 5.
(602) What type of manual valve can be used to control the rate of product flow?
- A.
Plug
- B.
Gauge
- C.
Check
- D.
Globe
Correct Answer
D. GlobeExplanation
A globe valve can be used to control the rate of product flow. Globe valves have a spherical-shaped body with an internal baffle, which creates a tortuous path for the fluid to flow through. By adjusting the position of the valve's disc, the flow rate can be regulated. This makes globe valves suitable for controlling the rate of fluid flow in various applications, including industrial processes and pipelines.Rate this question:
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- 6.
(602) The manual valve that can be repacked while the line is under pressure is the
- A.
Ball
- B.
Globe
- C.
Resilient-liner plug
- D.
Moveable seat plug
Correct Answer
B. GlobeExplanation
A globe valve is the manual valve that can be repacked while the line is under pressure. This is because a globe valve has a disc that moves perpendicular to the flow of the fluid, allowing for easy repacking of the valve while the line is still pressurized. In contrast, other types of valves such as ball valves or plug valves require the line to be depressurized before repacking can be done.Rate this question:
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- 7.
(602) What type packing is used around the valve stems of globe valves?
- A.
Nylon
- B.
Viton
- C.
Teflon string
- D.
Graphite
Correct Answer
C. Teflon stringExplanation
Teflon string is used as packing around the valve stems of globe valves. Teflon, also known as polytetrafluoroethylene (PTFE), is a synthetic material that is highly resistant to chemicals, heat, and friction. It is a popular choice for valve stem packing because it provides a tight seal, prevents leaks, and reduces friction between moving parts. Teflon string is flexible and can be easily wrapped around the valve stem to create a reliable seal, making it an ideal choice for globe valves.Rate this question:
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- 8.
(603) How often do you operationally inspect a lubricated plug valve?
- A.
Monthly
- B.
Quarterly
- C.
Annually
- D.
As required
Correct Answer
B. QuarterlyExplanation
The correct answer is Quarterly. Lubricated plug valves are critical components in industrial systems, and regular operational inspections are necessary to ensure their proper functioning. Performing inspections on a quarterly basis allows for timely identification of any issues or wear and tear that may affect the valve's performance. This frequency strikes a balance between frequent inspections to catch potential problems early and not overwhelming maintenance resources with inspections that are too frequent.Rate this question:
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- 9.
(603) What type of valve does not have to be removed from the pipeline during hydrostatic testing?
- A.
Ball valve
- B.
Gate valve
- C.
Resilient liner plug valve
- D.
Double block and bleed plug valve
Correct Answer
D. Double block and bleed plug valveExplanation
A double block and bleed plug valve is designed in such a way that it can isolate the pipeline on both sides of the valve, and also has a bleed valve to release any trapped pressure between the two blocks. This means that during hydrostatic testing, the valve does not need to be removed from the pipeline as it can effectively isolate the section being tested and also release any pressure if needed.Rate this question:
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- 10.
(603) What prevents leakage past the hub of the resilient-liner plug valve?
- A.
O-ring
- B.
Diaphragm seal
- C.
Asbestos gasket
- D.
Graphite packing
Correct Answer
B. Diaphragm sealExplanation
A diaphragm seal prevents leakage past the hub of the resilient-liner plug valve. This type of seal is designed to create a tight and secure barrier between the valve and the surrounding environment, preventing any fluid or gas from escaping. The diaphragm seal acts as a flexible membrane that can withstand pressure and movement, ensuring that no leakage occurs. Unlike other options such as an O-ring, asbestos gasket, or graphite packing, a diaphragm seal offers superior sealing capabilities and is commonly used in applications where leakage prevention is crucial.Rate this question:
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- 11.
(603) How often do non-lubricated plug valve have to be inspected for ease operation and leaks?
- A.
Weekly
- B.
Monthly
- C.
Annually
- D.
As required
Correct Answer
D. As requiredExplanation
Non-lubricated plug valves do not require regular inspections for ease of operation and leaks like lubricated valves. Instead, they need to be inspected and maintained as required based on their specific usage and operating conditions. This means that the frequency of inspections will depend on factors such as the valve's age, usage, environment, and any signs of potential issues. Regular monitoring and maintenance are necessary to ensure optimal performance and prevent any potential leaks or operational difficulties.Rate this question:
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- 12.
(603) A 12-inch non-lubricated plug valve will have what type of operator?
- A.
Lever
- B.
Chain
- C.
Wrench
- D.
Worm gear
Correct Answer
D. Worm gearExplanation
A 12-inch non-lubricated plug valve will have a worm gear operator. A worm gear is a type of gear mechanism that consists of a screw-like gear (worm) and a wheel-like gear (worm wheel). This type of operator provides a high gear ratio, allowing for precise and controlled movement of the valve. It is commonly used in applications where manual operation of the valve is required, especially in cases where lubrication is not possible or recommended.Rate this question:
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- 13.
(603) What position must a General Twin Seal plug valve be in so that you can remove the valve operator?
- A.
Open
- B.
Closed
- C.
Either open or closed
- D.
Intermediate between open and closed
Correct Answer
B. ClosedExplanation
To remove the valve operator of a General Twin Seal plug valve, the valve must be in the closed position. This is because in the closed position, the plug is fully engaged with the valve seat, creating a tight seal and preventing any flow through the valve. By removing the valve operator in this position, maintenance or repairs can be performed without any risk of leakage or flow.Rate this question:
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- 14.
(604) Which of the following manual valves is a suitable substitute for a non-lubricated plug valve?
- A.
Ball
- B.
Globe
- C.
Check
- D.
Butterfly
Correct Answer
A. BallExplanation
A ball valve is a suitable substitute for a non-lubricated plug valve. Both valves have a similar design and function, with a rotating mechanism to control the flow of fluid. The ball valve has a spherical-shaped disc that rotates within the valve body, allowing for smooth and efficient operation. It provides a tight seal and is commonly used in applications where tight shut-off is required. Therefore, a ball valve can effectively replace a non-lubricated plug valve in various industrial settings.Rate this question:
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- 15.
(604) What type of valve used in fuel systems must be fire tested and qualified in accordance with the requirements of API standard 607 and operate from fully closed to fully open with a 90 degree rotation of the ball?
- A.
Gate
- B.
Ball
- C.
Plug
- D.
Globe
Correct Answer
B. BallExplanation
Ball valves are used in fuel systems and must be fire tested and qualified according to API standard 607. These valves operate from fully closed to fully open with a 90-degree rotation of the ball. Therefore, the correct answer is ball.Rate this question:
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- 16.
(604) How often do ball valves have to be inspected for ease of operation and leaks?
- A.
Weekly
- B.
Monthly
- C.
Quarterly
- D.
As required
Correct Answer
D. As requiredExplanation
Ball valves do not have a specific inspection schedule as their frequency of inspection depends on their usage and condition. They should be inspected for ease of operation and leaks whenever there are signs of malfunction or when routine maintenance is being conducted. The frequency of inspection may vary based on factors such as the type of fluid being controlled, the environment in which the valve is installed, and the manufacturer's recommendations. Therefore, ball valves should be inspected as required, rather than on a fixed schedule.Rate this question:
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- 17.
(605) To conform to API Standard 6D, the seat and disc of which valve must be removable without removing the valve from the pipeline?
- A.
Gate
- B.
Plug
- C.
Globe
- D.
Check
Correct Answer
D. CheckExplanation
In order to conform to API Standard 6D, the seat and disc of a Check valve must be removable without removing the valve from the pipeline. This means that the Check valve can be maintained and repaired without having to shut down the entire pipeline system. Gate, Plug, and Globe valves do not have this specific requirement, so they would not be the correct answer in this case.Rate this question:
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- 18.
(605) What type of valve requires the least amount of space?
- A.
Ball
- B.
Gate
- C.
Check
- D.
Butterfly
Correct Answer
D. ButterflyExplanation
Butterfly valves require the least amount of space compared to other types of valves. This is because they have a compact design and a simple mechanism that allows for easy installation and operation. The disc of the butterfly valve is positioned in the center of the pipe, allowing for a straight flow path and minimal obstruction. Additionally, butterfly valves are lightweight and can be installed in tight spaces, making them a preferred choice when space is limited.Rate this question:
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- 19.
(605) What type of valve must be fully closed before you can remove it from the pipeline?
- A.
Ball
- B.
Gate
- C.
Butterfly
- D.
Non-lubricated plug
Correct Answer
C. ButterflyExplanation
A butterfly valve must be fully closed before it can be removed from the pipeline. This is because a butterfly valve operates by rotating a disc in the pipeline to control the flow of fluid. In order to remove the valve, the disc needs to be in the closed position to prevent any leakage or flow of fluid. Once the valve is fully closed, it can be safely removed from the pipeline for maintenance or replacement.Rate this question:
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- 20.
(606) Whom must you notify before you work on a fuel system that could interfere with the base flying mission?
- A.
Wing safety
- B.
Base operations
- C.
Resource control center
- D.
Command fuels engineer
Correct Answer
C. Resource control centerExplanation
Before working on a fuel system that could interfere with the base flying mission, you must notify the Resource Control Center. This is because the Resource Control Center is responsible for managing and coordinating the use of resources, including fuel, on the base. They need to be informed about any work that could potentially affect the availability or functionality of the fuel system to ensure that it does not disrupt the base's flying mission.Rate this question:
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- 21.
(606) What specialized equipment must you have to ensure system integrity when removing a valve from the system?
- A.
Locks
- B.
Drip pans
- C.
Blind flanges
- D.
As built drawings
Correct Answer
C. Blind flangesExplanation
Blind flanges are specialized equipment that must be used to ensure system integrity when removing a valve from the system. Blind flanges are solid disks used to close off a pipeline or vessel opening. They are designed to prevent any flow through the system while maintenance or repairs are being carried out. By using blind flanges, the system is effectively sealed and protected from any potential leaks or contamination during the valve removal process.Rate this question:
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- 22.
(606) Where would you find out which valves have to be isolated before removing a manual valve?
- A.
Co-workers
- B.
Shop supervisor
- C.
As built drawings
- D.
Air Force standard drawings
Correct Answer
C. As built drawingsExplanation
As-built drawings are detailed diagrams or blueprints that show the exact layout and configuration of a system or structure as it was constructed. These drawings typically include information about the location and operation of valves, pipes, and other components. Therefore, consulting as-built drawings would provide the necessary information to identify which valves need to be isolated before removing a manual valve. This is because the as-built drawings would accurately depict the current state and arrangement of the valves in the system.Rate this question:
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- 23.
(606) How much fuel is in a 22-foot section of 6-inch pipe?
- A.
11 gallons
- B.
22 gallons
- C.
33 gallons
- D.
44 gallons
Correct Answer
C. 33 gallonsExplanation
The amount of fuel in a pipe can be calculated using the formula for the volume of a cylinder. The formula is V = πr^2h, where V is the volume, r is the radius, and h is the height. In this case, the radius is half the diameter, so it is 3 inches. The height is the length of the pipe, which is 22 feet. Converting the measurements to the same unit, we have a radius of 0.25 feet and a height of 22 feet. Plugging these values into the formula, we get V = π(0.25)^2(22) = 33 gallons. Therefore, the correct answer is 33 gallons.Rate this question:
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- 24.
(606) When removing a manual valve from a pipeline, which bolts on the valve should you loosen first to drain the fuel drip pan?
- A.
Top
- B.
Bottom
- C.
Left side
- D.
Right side
Correct Answer
B. BottomExplanation
When removing a manual valve from a pipeline, the bolts on the bottom of the valve should be loosened first to drain the fuel drip pan. Loosening the bottom bolts will allow any fuel or liquid in the valve and drip pan to flow out, preventing spills or leaks during the removal process. By starting with the bottom bolts, the fuel can be safely drained before proceeding with the removal of the valve.Rate this question:
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- 25.
(606) When reinstalling a manual valve, which bolts should you insert first?
- A.
Top
- B.
Bottom
- C.
Left side
- D.
Right side
Correct Answer
B. BottomExplanation
When reinstalling a manual valve, it is recommended to insert the bottom bolts first. This is because the weight of the valve can be better supported when the bottom bolts are secured first. By starting with the bottom bolts, it ensures that the valve is properly aligned and positioned before securing the remaining bolts on the top, left side, and right side.Rate this question:
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- 26.
(606) The system configuration that would not require you to manually bleed air out of the pipeline after a valve is replaced involves pumping
- A.
Through a meter
- B.
Though a fill stand
- C.
Though a filter/separator
- D.
Directly into a storage tank
Correct Answer
D. Directly into a storage tankExplanation
Directly pumping into a storage tank would not require manual bleeding of air out of the pipeline after a valve is replaced. This is because the storage tank acts as a reservoir where any air can naturally rise to the top and be vented out, without the need for manual intervention. Pumping through a meter, fill stand, or filter/separator would not provide the same capability to release trapped air, hence manual bleeding would be required in those cases.Rate this question:
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- 27.
(607) The main difference between the internal gear pump and the external gear pump lies in
- A.
The size of the pumping chamber
- B.
The amount of pressure applied
- C.
Where the fuel flows
- D.
The number of gears
Correct Answer
C. Where the fuel flowsExplanation
The main difference between the internal gear pump and the external gear pump lies in where the fuel flows. In an internal gear pump, the fuel flows between the teeth of the gears and the inner surface of the pump housing. On the other hand, in an external gear pump, the fuel flows between the teeth of the gears and the outer surface of the pump housing. This difference in flow path affects the efficiency and performance of the pumps.Rate this question:
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- 28.
(608) What type of pump has a build-in pressure control valve?
- A.
Rotary-vane type
- B.
External gear
- C.
Deep-well turbine
- D.
Centrifugal
Correct Answer
A. Rotary-vane typeExplanation
A rotary-vane type pump has a built-in pressure control valve. This type of pump uses rotating vanes to create suction and move fluid. The built-in pressure control valve helps regulate the pressure within the pump, preventing it from exceeding a certain level. This feature is useful in applications where maintaining a specific pressure is important, such as in hydraulic systems or fuel delivery systems.Rate this question:
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- 29.
(608) What type of lubricant is used and how is it applied to he Blackmer pump ball bearings?
- A.
Liquid being pumped; bypass line
- B.
Liquid being pumped; internal pump pressure
- C.
Lithium-based grease; Lithium-based grease; grease cup
- D.
Lithium-based grease; hand-pressure gun
Correct Answer
D. Lithium-based grease; hand-pressure gunExplanation
Lithium-based grease is used to lubricate the ball bearings of the Blackmer pump. It is applied using a hand-pressure gun.Rate this question:
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- 30.
(608) What is used to remove the seals and bearings from the head of a rotary-vane type pump?
- A.
Mallet
- B.
Pliers
- C.
Screwdriver
- D.
Gear puller
Correct Answer
C. ScrewdriverExplanation
A screwdriver is used to remove the seals and bearings from the head of a rotary-vane type pump. This tool is commonly used to loosen and remove screws or fasteners. In the context of a pump, a screwdriver can be used to unscrew and remove the components that hold the seals and bearings in place, allowing for their removal and replacement if necessary.Rate this question:
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- 31.
(608) To adjust a rotary-vane pump pressure-relief control, you turn it in what direction, with what effect?
- A.
Clockwise; increase pump output
- B.
Clockwise; decrease delivery pressure
- C.
Counterclockwise; increase pump output
- D.
Counterclockwise; decrease delivery pressure
Correct Answer
D. Counterclockwise; decrease delivery pressureExplanation
Turning the rotary-vane pump pressure-relief control counterclockwise will decrease the delivery pressure. This means that the pump will produce less pressure when the control is adjusted in this direction.Rate this question:
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- 32.
(609) If a centrifugal pump develops 600gpm at 350 feet of head, how much psi is developed at 600gpm when pumping JP-8?
- A.
12.3 psi
- B.
34
- C.
3.3
- D.
123
Correct Answer
D. 123 -
- 33.
(609) What type of impeller in the centrifugal pump is the most efficient and develops the highest pressure?
- A.
Open
- B.
Closed
- C.
Semi-open
- D.
Combination
Correct Answer
B. ClosedExplanation
A closed impeller in a centrifugal pump is the most efficient and develops the highest pressure. This is because a closed impeller has a shroud that covers the entire impeller, preventing any fluid from escaping backwards. This design allows for more efficient transfer of energy from the rotating impeller to the fluid, resulting in higher pressure. Additionally, the closed impeller design reduces the risk of cavitation, which can negatively impact pump performance.Rate this question:
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- 34.
(609) At what rate will a Gillarco(R) self priming pump remove air?
- A.
18 inches per minute
- B.
28 inches per minute
- C.
18 gallons per minute
- D.
28 gallons per minute
Correct Answer
C. 18 gallons per minuteExplanation
A Gillarco self-priming pump is capable of removing air at a rate of 18 gallons per minute. This means that the pump is able to effectively remove air from a system or container at a speed of 18 gallons per minute. This rate is important in applications where air removal is necessary, such as in water or fluid transfer systems, to ensure efficient and effective operation.Rate this question:
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- 35.
(609) What should you do if the centrifugal pump binds after you have replaced parts in the self-priming pump portion a Gilbarco(R) pump?
- A.
File the rotor
- B.
File the vanes
- C.
Add 1/4 inch spacers
- D.
Add a paper-thin gasket
Correct Answer
D. Add a paper-thin gasketExplanation
If the centrifugal pump binds after replacing parts in the self-priming pump portion of a Gilbarco(R) pump, adding a paper-thin gasket can help resolve the issue. This gasket can create a small separation between the parts, allowing them to move freely and preventing binding.Rate this question:
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- 36.
(609) What type of pump is the API 610 pump?
- A.
Single stage centrifugal, radial split case, with end suction and discharge
- B.
Dual stage centrifugal, radial split case, with end suction and discharge
- C.
Single stage centrifugal, radial split case, with end suction and top discharge
- D.
Dual stage centrifugal, radial split case, with end suction and top discharge
Correct Answer
C. Single stage centrifugal, radial split case, with end suction and top dischargeExplanation
The API 610 pump is a single stage centrifugal pump with a radial split case design. It has an end suction and top discharge configuration.Rate this question:
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- 37.
(609) What is the maximum tolerance allowed when aligning an API 610 pump shaft and motor shaft?
- A.
0.001 inches
- B.
0.002 inches
- C.
0.003 inches
- D.
0.004 inches
Correct Answer
B. 0.002 inchesExplanation
When aligning an API 610 pump shaft and motor shaft, the maximum tolerance allowed is 0.002 inches. This means that the misalignment between the two shafts should not exceed 0.002 inches.Rate this question:
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- 38.
(609) How often is an API 610 pump operationally inspected?
- A.
Monthly
- B.
Quarterly
- C.
Semi-annually
- D.
Annually
Correct Answer
B. QuarterlyExplanation
API 610 pumps are operationally inspected on a quarterly basis. This means that the pump is checked for any operational issues or malfunctions every three months. This regular inspection helps to ensure that the pump is functioning properly and can identify any potential problems early on. By inspecting the pump on a quarterly basis, any necessary maintenance or repairs can be done promptly, minimizing downtime and maximizing the pump's efficiency and lifespan.Rate this question:
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- 39.
(610) The number of column-shaft sections a deep-well turbine will have is determined by the
- A.
Capacity of a tank
- B.
Pump output capacity
- C.
Distance between the tank roof and tank bottom
- D.
Distance between the pump tank flange and the tank floor
Correct Answer
D. Distance between the pump tank flange and the tank floorExplanation
The number of column-shaft sections a deep-well turbine will have is determined by the distance between the pump tank flange and the tank floor. This is because the column-shaft sections need to be long enough to reach from the pump tank flange to the tank floor in order to properly function. If the distance between these two points is too large, more column-shaft sections will be needed to cover the distance. Conversely, if the distance is smaller, fewer column-shaft sections will be required. Therefore, the distance between the pump tank flange and the tank floor directly affects the number of column-shaft sections needed.Rate this question:
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- 40.
(610) When adjusting impeller clearances in a deep-well turbine pump. what type of impeller is raised all the of the way up and then backed off one full turn?
- A.
Open
- B.
Closed
- C.
Semi-open
- D.
Semi-Closed
Correct Answer
B. ClosedExplanation
When adjusting impeller clearances in a deep-well turbine pump, the closed type of impeller is raised all the way up and then backed off one full turn. This allows for proper adjustment of the impeller clearance, ensuring efficient and effective pumping performance.Rate this question:
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- 41.
(611) You are replaceing a mechanical seal on a deep-well turbine with threaded couplings. You turn the couplings in which directiohn to disconnect it? With what do you cover the shaft threads to protect the mechanical O-ring?
- A.
Counterclockwise; grease
- B.
Counterclockwise; tape
- C.
Clockwise; tape
- D.
Clockwise; grease
Correct Answer
C. Clockwise; tapeExplanation
When replacing a mechanical seal with threaded couplings, the couplings should be turned clockwise to disconnect them. This is because turning them clockwise will loosen and unscrew the couplings. To protect the mechanical O-ring, tape should be used to cover the shaft threads. This will prevent any damage to the O-ring and ensure a proper seal when the new mechanical seal is installed.Rate this question:
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- 42.
(611) What action should you take if you notice a slight leak on a mechanical seal you have just installed?
- A.
Replace the O-ring
- B.
Replace the seal and O-ring
- C.
Stop the pump, restart, and see what happens
- D.
Allow reasonable time for the seals to adjust
Correct Answer
D. Allow reasonable time for the seals to adjustExplanation
When a slight leak is noticed on a mechanical seal that has just been installed, the appropriate action to take is to allow reasonable time for the seals to adjust. This is because mechanical seals require some time to settle and form a proper seal. By allowing time for adjustment, the seals may tighten and the leak may stop on its own. Replacing the O-ring or the entire seal immediately may not be necessary if the leak is minor and can potentially resolve itself with time. Restarting the pump or replacing parts may not address the issue and could potentially cause further damage.Rate this question:
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- 43.
(612) The components of the 81AF, nonsurge check valve, are one check valve (CV) flow control, a variable position indicator (VPI) , and
- A.
One hytrol check valve
- B.
Two hytrol check valves
- C.
One swing check valve
- D.
Two swing check valves
Correct Answer
D. Two swing check valvesExplanation
The correct answer is two swing check valves. The question states that the components of the 81AF nonsurge check valve include a check valve (CV) flow control, a variable position indicator (VPI), and "two swing check valves." This implies that there are two swing check valves included in the 81AF nonsurge check valve.Rate this question:
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- 44.
(612) To speed up the opening time of an 81AF, nonsurge check valve, you must turn the check valve (CV) flow control adjusting screw
- A.
Counterclockwise to increase
- B.
Counterclockwise to decrease
- C.
Clockwise to increase
- D.
Clockwise to decrease
Correct Answer
C. Clockwise to increaseExplanation
To speed up the opening time of an 81AF, nonsurge check valve, you must turn the check valve (CV) flow control adjusting screw clockwise to increase. This means that by turning the screw in a clockwise direction, the flow control will be increased, resulting in a faster opening time for the check valve.Rate this question:
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- 45.
(612) Which of the following conditions would cause the 81AF, nonsurge check valve, to open too rapidly or have no control of the opening rate?
- A.
A loose diaphragm washer
- B.
Air in the main cover chamber
- C.
A swing check valve disc stuck off its seat
- D.
An obstruction between the disc and the seat of the main valve
Correct Answer
C. A swing check valve disc stuck off its seatExplanation
If the swing check valve disc is stuck off its seat, it means that the disc is not properly seated and is not able to control the flow of fluid. This can cause the valve to open too rapidly or have no control over the rate of opening. When the disc is stuck off its seat, it can allow the fluid to flow freely without any restriction, leading to rapid or uncontrolled opening of the valve.Rate this question:
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- 46.
(612) When reverse flow occurs to an 81AF08, nonsurge check valve, how does fuel get to the cover chamber of the hytrol check valve?
- A.
Through a drilled passage
- B.
Through a pin hole in the hytrol check valve diaphragm
- C.
Tubing connected from the inlet of the main valve to the cover chamber of the hytrol check
- D.
Tubing connected from the outlet of the main valve to the cover chamber of the hytrol check
Correct Answer
A. Through a drilled passageExplanation
When reverse flow occurs to an 81AF08, nonsurge check valve, fuel gets to the cover chamber of the hytrol check valve through a drilled passage.Rate this question:
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- 47.
(612) What is the standard opening rate for the 81AF-8, nonsurge check valve?
- A.
10 seconds
- B.
20 seconds
- C.
30 seconds
- D.
40 seconds
Correct Answer
B. 20 secondsExplanation
The standard opening rate for the 81AF-8, nonsurge check valve is 20 seconds. This means that it takes approximately 20 seconds for the valve to fully open once it is activated.Rate this question:
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- 48.
(612) What would cause the 81AF-8, nonsurge check valve to fail to open?
- A.
Loose diaphragm washer
- B.
Hytrol check installed backwards
- C.
Closed downstream manual valve
- D.
Air in the main valve cover chamber
Correct Answer
C. Closed downstream manual valveExplanation
If the downstream manual valve is closed, it will prevent the flow of fluid or air, causing the 81AF-8 nonsurge check valve to fail to open. The downstream manual valve acts as a barrier, blocking the passage of fluid or air and preventing it from reaching the check valve. As a result, the check valve cannot open and allow the flow to pass through.Rate this question:
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- 49.
(613) The newest filter/separator modification requires how many cartridges total for a 600-gpm filter/separator?
- A.
15
- B.
20
- C.
25
- D.
30
Correct Answer
D. 30Explanation
The newest filter/separator modification requires a total of 30 cartridges for a 600-gpm filter/separator. This suggests that the modification involves a significant increase in the number of cartridges compared to previous versions. The higher number of cartridges is likely necessary to effectively filter and separate the fuel at a flow rate of 600 gallons per minute.Rate this question:
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- 50.
(613) In a horizontal filter/separator, what will change the position and to what valve will pressure be directed when the float of the pilot valve assembly is in the TOP position?
- A.
Rotary disc; water drain valve
- B.
Rotary disc; fuel discharge valve
- C.
Adapter mounting rod; water drain valve
- D.
Adapter mounting rod; fuel discharge valve
Correct Answer
B. Rotary disc; fuel discharge valveExplanation
When the float of the pilot valve assembly is in the TOP position in a horizontal filter/separator, it will change the position of the rotary disc. This change in position of the rotary disc will direct the pressure to the fuel discharge valve.Rate this question:
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Current Version
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Mar 20, 2023Quiz Edited by
ProProfs Editorial Team -
Sep 26, 2010Quiz Created by
JiminyCricket
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