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Question 21: Lean sour gas is a type of natural gas that: Has a low concentration of hydrogen sulfide

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Question 22:
Which of the following natural gas components is considered a contaminant?

A - Hydrogen sulphide
B - Helium
C - Carbon dioxide
D - Nitrogen
_______________________________________________

Question 23:
The formula C4H10represents:

A - Ethane
B - Propane
C - Butane
D - Methane

 

PIPE 6010_Valve Actuators


Question 1:
A solution to the high torque required to operate larger valves is to equip the valve with a gear system so that:
A - The valve can be closed much tighter
B - The position of the valve can be more precisely regulated
C - The valve can be opened and closed much quicker than without a gear
D - It is easier for the operator to open and close the valve
_______________________________________________

Question 2:
When it is desired to position the valve plug of a pneumatic piston actuator at any intermediate position a:
A - Worm gear is required
B - Positioner is required
C - Solenoid is required
D - Mechanical linkage system is required
_______________________________________________

Question 3:
A preloaded type actuator has a large air dome on top of the diaphragm which replaces the:
A - Worm and gear
B - Piston
C - Coil
D - Spring
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Question 4:

____________________ actuators are used when the force required to position a valve or damper is higher than that which can be provided by a diaphragm.
A - Spring loaded diaphragm
B - Pneumatic piston
C - Mechanical
D - Solenoid driven
_______________________________________________

Question 5:Large motorized valves are equipped with limit switches: A - To open the motor electrical circuit at each extreme travel B - To open the motor electrical circuit when a predetermined torque has been developed by the motor C - To cause an increase in speed of response to a control signal D - Both a and b

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Question 6:
The air used to operate a pneumatic valve actuator must be free of:
A - Oil and nitrogen
B - Water and oxygen
C - Oil and water
D - Water and carbon dioxide
_______________________________________________

Question 7:
The air supply system for pneumatic actuators that receive an air supply from a source separate from that supplying the controller is usually equipped with a __________ to collect condensed ________________.
A - sump, moisture
B - valve, solids
C - sump, solids
D - filter, moisture
_______________________________________________

Question 8:
A solenoid operated valve may be used to control the position of the disc in a globe valve when the:
A - Spring in the actuator requires extra force to open the valve
B - Valve plug must be modulated at intermediate positions
C - Valve must be fully open or fully closed
D - Response speed of the actuator must be increased
_______________________________________________

Question 9:
Solenoid valves are employed in small size systems where:
A - On-off operation is required
B - Modulating service is required in day-to-day operations
C - The position of the valve must be precisely regulated
D - A reversed actuator is used to control the valve
_______________________________________________



Question 10:
Chain and wheel operators are used for valves that:
A - Cannot be operated by one person
B - Cannot be located within easy reach
C - Require automatic valve positioning using a remote operating device
D - Require electro-hydraulic operators and a remote operating device
_______________________________________________

Question 11:
Equipping larger valves with a gear system is one solution to the ________________ required to operate the valve.
A - low torque
B - handwheel
C - high torque
D - additional manpower
_______________________________________________

Question 12:
Pneumatic or hydraulic piston actuators are used when:
A - A much greater stem movement is required than a diaphragm actuator can provide
B - The air used for control purposes is contaminated with moisture, oil or particles of dirt
C - The force required to position a valve or a damper is less than that which can be provided by a diaphragm
D - Both a and c
_______________________________________________

Question 13:
Air loaded diaphragm actuators are considered superior to spring loaded types in many applications because:
A - The spring and the unbalanced force on the valve plug oppose the air pressure on the diaphragm
B - Spring action can be erratic and the force provided by the spring is constant at any degree of compression
C - Spring action is constant but the force provided by the spring is erratic at any degree of compression
D - Differential control is achieved by a single air pressure signal
_______________________________________________

Question 14:
A pneumatic actuator converts an air signal into valve stem motion by:
A - Operating the solenoid by air pressure
B - Telemetry
C - Applying pressure to a diaphragm
D - All of the above
_______________________________________________

Question 15:
With an air loaded diaphragm actuator design:
A - A spring and the unbalanced force on the valve plug, due to the process pressure, opposes the air pressure on the diaphragm
B - Two air signal pressures control the valve differentially
C - Differential control is achieved by a single air pressure signal
D - Spring action is constant but the force provided by the spring is erratic at any degree of compression
_______________________________________________

Question 16:
Pneumatic actuators are:
A - Never used for on-off operation
B - Only used for on-off operation
C - Rarely used for modulating service
D - Typically used for modulating service
_______________________________________________

Question 17:
Pneumatic actuators are widely used in the petroleum and chemical industries because:
A - Instrument air is readily available
B - They are less expensive than other actuators
C - They are safe, simple and reliable
D - They are most popular for on-off operation
_______________________________________________

Question 18:
Pneumatic actuators are typically used for modulating service and are never used for on-off operation.
A - True
B - False
_______________________________________________

Question 19:
In a small, low-pressure application where throttling service is not required of valves, the most appropriate and cost-effective valve actuator would be a/an:

A - Solenoid
B - Chain and wheel
C - Electric motor
D - Geared hand-crank
_______________________________________________

Question 20:
The main disadvantage of an electric valve operator is:

A - The valves must be installed at the appropriate operating levels
B - They cannot be operated from several locations
C - They are relatively expensive, in both equipment and wiring costs
D - That only a small range of valve operating speeds can be obtained


BLRS 6021_Pressure Safety Devices

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Question 1:
A spring-loaded device that acts as a safety valve in gas service and as a relief valve in liquid service is called a:
A - Pilot-operated pressure-relief valve
B - Water sealed safety-relief device
C - Relief valve
D - Safety-relief valve
_______________________________________________

Question 2:
A pilot-operated pressure relief valve is a valve in which the major relieving device is combined with, and is controlled by a:

A - Self-actuated gate valve
B - Water sealed safety-relief valve
C - Manually operated pressure-relief valve
D - Self-actuated pressure-relief valve
_______________________________________________

Question 3:
The type of safety valve shown in the illustration seen here is a:

A - Conventional safety-relief valve
B - Power-actuated pressure-relief valve
C - Pilot-operated pressure-relief valve
D - Water sealed safety-relief valve
_______________________________________________

Question 4:
Power-actuated relief valves can be used instead of code-required safety valves as they do essentially the same job.
A - True
B - False
_______________________________________________

Question 5:
The pressure safety device in which the major relieving device is combined with, and is controlled by a self-actuated pressure-relief valve is the:

A - Pilot-operated pressure-relief valve
B - Water sealed safety-relief device
C - Safety-relief valve
D - Power-actuated pressure-relief valve
_______________________________________________

Question 6:
A relief valve is a spring-loaded device that begins to open when the inlet pressure reaches set pressure, overcomes the spring force, and begins to lift the disk off the seat. It is used in:
A - Gas service
B - Liquid service
C - Steam service
D - All of the above
_______________________________________________

Question 7:
In a pilot-operated safety-relief valve, pressure is exerted on both sides of the main valve. The valve is held closed because the dome surface area is:
A - Larger than the system side
B - Smaller than the system side
C - The same size as the system side
D - None of the above

_______________________________________________

Question 8:
Inadvertent contact between the lifting cam and the spindle nut of a pressure relief valve may be the result of:
A - Vibration and pulsing pressure
B - Incorrectly adjusting lifting gear
C - Damaged springs
D - Rough handling
_______________________________________________

Question 9:
Pilot-operated safety-relief valves are primarily used:
A - In general refinery process service
B - Where chemical compatibility of the process fluid with the diaphragms is questionable
C - Where there is low differential between normal operating pressures and set pressure of the valve
D - In viscous liquid service
_______________________________________________

Question 10:
The operational characteristics of a conventional safety-relief valve are directly affected by changes in the:
A - Process flow
B - Valve outlet pressure
C - Backpressure on the valve
D - Tension on the main spring
_______________________________________________

Question 11:
Pilot-operated safety-valves are not used:
A - In viscous liquid service
B - Where large relief areas at high set pressure are required
C - On large, low-pressure storage tanks
D - Where very short blowdown is required
_______________________________________________

Question 12:
A pressure gauge, a try cock, a free vent, or a suitable indicator should be inserted _____________ a rupture disk device installed at the ___________ of a pressure-relief valve and the valve itself to detect disk rupture or leakage.

A - beside; outlet
B - between; inlet
C - between; outlet
D - beside; inlet
_______________________________________________

Question 13:
Damaged flanges and misaligned valve parts of a pressure-relief valve can result from:

A - Vibration and pulsating pressure
B - Leakage
C - Rough handling
D - Incorrect calibration
_______________________________________________

Question 14:
Which pressure relief valve problem could cause the disk to rub against the seat, resulting in leakage?
A - Incorrect calibration
B - Vibrating and pulsating pressure
C - An incorrectly adjusted lifting gear
D - Damaged springs
_______________________________________________

Question 15:
If you were designing a system where any superimposed backpressure is constant and any built-up backpressure will not exceed 10% of the set pressure, the type of safety pressure device that you would include in your design should be a:
A - Conventional safety-relief valve
B - Water-sealed safety-relief valve
C - Rupture disk
D - Power-actuated pressure-relief valve
_______________________________________________

Question 16:
The safety-relief device that is referred to as a non-reclosing pressure relief device is a:
A - Pilot-operated pressure-relief valve
B - Relief valve
C - Water sealed safety-relief device
D - Rupture disk
_______________________________________________

Question 17:
Rupture disks are used to protect:

A - The upstream side of pressure valves against corrosion by the system fluid
B - The downstream side of pressure relief valves against atmospheric corrosion
C - Pressure relief valves against plugging or clogging by viscous fluids
D - All of the above
_______________________________________________

Question 18:
The safety valve has a valve disk that is held firmly on its seat by:
A - A carbon-steel casing welded directly to the pipe
B - Two adjustable nuts that are equipped with locknuts
C - The pressure of the process flow
D - The pressure of a heavy coil spring
_______________________________________________

Question 19:
When maximum pressure is reached, the metal membrane of a rupture disk fails and:
A - Blows apart in fragments
B - Dissolves
C - Gradually relieves the pressure
D - Peels open
_______________________________________________

Question 20:
The force of the pressure acting on the safety valve disk is a function of:
A - Seat diameter
B - Spring tension
C - Disk area
D - Percentage of valve opening

 


PIPE_6007_Specialized_Valves


Question 1:
Pressure relief valves start to open at a preset pressure but require __________ overpressure to open wide.

A - 20%
B - 15%
C - 10%
D - 5%
_______________________________________________

Question 2:
Blow-off valves are designed and installed in accordance with the __________ code in systems where blow-down _____________ is necessary.

A - ASME, rapid cooling
B - ASME, drainage
C - APPEGA, rapid cooling
D - APPEGA, drainage
_______________________________________________

Question 3:
The type of blow-off valve used on high-pressure boilers is a:

A - Pressure safety valve
B - Seat-and-disc valve
C - Diaphragm valve
D - Single seated balance valve
_______________________________________________

Question 4:
Some blowoff valves are made with integral seats made by depositing a hard-facing material, such as stellite, directly on the body of the valve. When such a seat starts to leak, the seating surface:

A - Is self-repairing as the stellite conforms to pressure variations
B - Can be re-inserted while the valve remains in place in the pipeline
C - Must be refaced immediately
D - Can be re-cut or reground while the valve remains in place in the pipeline
_______________________________________________

Question 5:
A ________________________ is the best choice of valve for applications in which the process fluid is highly flammable, expensive, corrosive, toxic, or explosive and where tight shutoff is necessary.

A - Double-seated balance valve
B - Double-ported valve
C - Single-seated single-port balance valve
D - Sliding-disc blow-off valve
_______________________________________________

Question 6:
Weight-operated balanced reducing valves are used to regulate pressure for:

A - Downstream only
B - Upstream only
C - Backpressure control only
D - Both upstream and downstream
_______________________________________________

Question 7:
In a diaphragm valve, the mechanism that moves the diaphragm is completely ______________from the fluid and no __________________________ is required.

A - Integrated, valve wheel
B - Integrated, packing material
C - Separated, packing material
D - Separated, valve wheel
_______________________________________________

Question 8:
The force required to position the plug of a pilot operated high pressure regulator is obtained from:

A - An external pilot unit and piston-type actuator
B - An externally mounted compression spring
C - An internal flexible diaphragm
D - A thermostat which signals the spring-loaded closing element
_______________________________________________

Question 9:
When compared to a single-seated balance valve, a double-seated balance valve has greater difficulty in achieving tight shutoff because:

A - The double-seated valve usually has a smaller port area
B - The temperature causes the stem to expand, increasing the distance between the plugs
C - It can pass up to twice as much fluid as a single-seated valve
D - More power is required to operate a double-seated valve
_______________________________________________

Question 10:
The bypass valve utilized in a pressure reducing station which throttles the flow during reducing valve maintenance should be a:

A - Gate valve
B - Ball valve
C - Butterfly valve
D - Globe valve
______________________________________________

Question 11:
For mixing fluids, the mixing valve is designed with:

A - One inlet and two discharge outlets
B - One inlet, one discharge, and a drainage cock
C - Two inlets and one discharge outlet
D - Two inlets and two discharge outlets
_______________________________________________

Question 12:
Which type of valves are preferred for isolating the pressure reducing valve of a pressure reducing station?
A - Globe valves
B - Ball valves
C - Gate valves
D - Butterfly valves
_______________________________________________

Question 13:
The primary difference between pressure relief valves and pressure safety valves is that safety valves:

A - Pop wide open while relief valves open gradually
B - Operate against a compression spring while relief valves do not
C - Require 20% overpressure before they are fully open while relief valves are open at a set pressure
D - Will close completely when the pressure drops to the opening pressure while relief valves will close before the opening pressure is reached
_______________________________________________

Question 14:
In an application where the process fluid is highly flammable, expensive, corrosive, toxic, or explosive and where tight shutoff is necessary, the best choice of balance valve is a:

A - Sliding-disc blowoff valve
B - Double-seated balance valve
C - Double-ported valve
D - Single-seated single-port balance valve
_______________________________________________

Question 15:
For diverting fluids, the diverting valve is designed with:

A - One inlet, one discharge and a balancing pipe
B - Two inlets and one discharge outlet
C - One inlet and two discharge outlets
D - Two inlets and two discharge outlets

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Question 16:
The outlet pressure of a spring-loaded internal diaphragm pressure-reducing valve can be lowered by:

A - Increasing the fluid flow in the control line to the diaphragm
B - Turning the compression screw downward, into the bonnet
C - Throttling the downstream pressure to the top of the diaphragm
D - Reducing the compression of the valve spring
_______________________________________________

Question 17:
Safety valves provide a rapid means of getting rid of any excessive pressure before a serious accident occurs.

A - True
B False

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Question 18:
The rupture-disc relief valve is much like a diaphragm valve except that it has no bonnet but does have a control mechanism at the discharge.

A - True
B - False
_______________________________________________

Question 19:
The outlet pressure of a spring-loaded internal diaphragm pressure reducing valve can be increased by:

A - Throttling the downstream pressure to the top of the diaphragm
B - Increasing the fluid flow in the control line to the diaphragm
C - Turning the screw downward increasing the spring compression
D - Reducing the compression of the valve spring
_______________________________________________

Question 20:
A sliding-disc blow-off valve is used in combination with a:

A - Rupture disc
B - Mixing valve
C - Pressure reducing valve
D - Slow-opening valve
_______________________________________________

Question 21:
Why is the diaphragm in this illustration not affected by the temperature of the fluid in a spring-loaded pressure-reducing valve?

 


A - Because the low-pressure suction draws the fluid away from the diaphragm
B - because the diaphragm and spring are mounted outside the valve housing
C - Because the valve is not equipped with a diaphragm
D - Because the diaphragm is sealed behind the bearing

 


Date: 2016-01-05; view: 630


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