Review valves and hydro, valve maintainces Flashcards
Angle valves operate in the same way as?
1)
Ball valves
2)
Gate valves
3)
Globe valves
4)
Plug valves
3)
Globe valves
The valve installed on thermal storage tanks to prevent negative pressures is the?
1)
Pressure reducing valve
2)
Pressure relief valve
3)
Vacuum breaker
4)
Vacuum relief valve
3)
Vacuum breaker
A swing check valve can be installed in the?
1)
Horizontal position only
2)
Vertical position only
3)
Horizontal or vertical facing upwards
4)
Downward position
3)
Horizontal or vertical facing upwards
The valve that is often referred to as a “cock” or “bibb” is the?
1)
Ball valve
2)
Plug valve
3)
Globe valve
4)
Swing check valve
2)
Plug valve
When fully open, the valve that has the highest restriction of flow is?
1)
Ball valve
2)
Gate valve
3)
Globe valve
4)
Plug valve
3)
Globe valve
Valves made of malleable iron can be found in?
1)
Chemical waste lines
2)
Gas distribution systems
3)
High temperature systems
4)
Sub-zero temperatures
4)
Sub-zero temperatures
A pressure reducing valve (PRV) station is required when?
1)
The PRV valve is over 1/2” diameter
2)
The PRV valve is over 3/4” diameter
3)
The PRV valve is over 1” diameter
4)
The PRV valve is over 1 1/4” diameter
3)
The PRV valve is over 1” diameter
One type of valve used to prevent backflow in a piping system is a?
1)
Balancing valve
2)
Pressure vacuum breaker
3)
Stop and waste valve
4)
Vacuum relief valve
2)
Pressure vacuum breaker
Incorrect Response
The most common factor that causes the pressure rating of a valve to drop is?
1)
Rust
2)
Incorrect installation
3)
Increased temperatures
4)
Increased flow rates
3)
Increased temperatures
Three types of check valves are swing, lift and?
1)
Ball
2)
Globe
3)
Gate
4)
Plug
1)
Ball
When stamped on the body of a valve, the initials WOG are an abbreviation for:
1)
Hot water, oil, or gas
2)
Water, oxygen, or gas
3)
Waste, oxygen, or gas
4)
Cold water, oil, or gas
4)
Cold water, oil, or gas
The basic function of a pressure reducing valve is to?
1)
Either open or close to admit more or less water, as demanded by the system, at a relatively constant pressure.
2)
Control the pressure in the line by restricting the flow of water through the lines.
3)
Restrict the line pressure by controlling the pressure variation.
4)
Maintain the pressure variation by mechanically restricting to control pressure.
1)
Either open or close to admit more or less water, as demanded by the system, at a relatively constant pressure.
A strainer must be installed on the high pressure side of a PRV to?
1)
Prevent dirt from plugging the pressure actuating jet.
2)
Prevent dirt erosion of the valve seat.
3)
Prevent dirt from becoming stuck between the disc and seat.
4)
Prevent pressure surging.
3)
Prevent dirt from becoming stuck between the disc and seat.
“NO flow pressure” relative to PRV’s may be defined as?
Correct Answer
1)
Pressure maintained in the system by a PRV during no demand periods.
2)
Change in pressure below that which is needed to open the valve.
3)
Pressure maintained by the valve when water is flowing.
Incorrect Response
4)
Pressure below the reduced flow pressure which is needed to open the valve.
1)
Pressure maintained in the system by a PRV during no demand periods.
A parallel PRV installation might be necessary to?
1)
Allow pressure reduction great than the reduction capability of a single PRV.
2)
Provide staged reduction in down feed risers in tall buildings.
3)
Allow the use of two smaller cheaper valves in place of one large, expensive valve and at the same time eliminate the use for a bypass.
4)
Provide two stage reduction for systems operating at two different pressures.
3)
Allow the use of two smaller cheaper valves in place of one large, expensive valve and at the same time eliminate the use for a bypass.
One PRV in a parallel installation may be set in at a slightly higher opening pressure than the other to?
1)
Allow for reduction greater than the capacity of one PRV.
2)
Provide staged pressure reduction for high rise down feed riser installations.
3)
Allow a large valve/small valve installation with the small valve set to satisfy low flow demands.
4)
Allow for two stage reduction in systems operating at two different pressures.
3)
Allow a large valve/small valve installation with the small valve set to satisfy low flow demands.
The boiling temperature of water at atmospheric pressure is?
1)
180˚F
2)
200˚F
3)
210˚F
4)
212˚F
4)
212˚F
The temperature relief setting on a standard Temperature and Pressure Relief valve is?
1)
180˚F
2)
200˚F
3)
210˚F
4)
212˚F
3)
210˚F
What is “blowdown” in the context of PSVs?
1)
The maximum pressure the valve can handle
2)
The difference between the set pressure and the reseating pressure
3)
The rate at which the valve discharges
4)
The pressure at which the valve opens
2)
The difference between the set pressure and the reseating pressure
Which type of PSV is commonly used for compressible fluids like gases and vapors?
1)
Conventional spring-loaded PSV
2)
Pilot-operated PSV
3)
Balanced bellows PSV
4)
Lever-operated PSV
1)
Conventional spring-loaded PSV
How often should PSVs be tested in high-risk applications?
1)
Every month
2)
Every year
3)
Every five years
4)
Every decade
2)
Every year
What is the term for the testing method where the PSV is subjected to increasing pressure until it activates?
1)
Static testing
2)
Functional testing
3)
Burst testing
4)
Set pressure testing
4)
Set pressure testing
Which of the following is true about a double disc gate valve?
1)
It is positioned between the tapered seats to form a seal
2)
The disc and seat are parallel to each other and are not tapered
3)
It consists of two pieces that sit between two matching tapered seats in the body
4)
It is hollow around the edges and solid across the centre portion
2)
The disc and seat are parallel to each other and are not tapered
What is the recommended turn down ratio from the high pressure side to
the low pressure side of a pressure reducing valve?
1)
20 to 1
2)
5 to 1
3)
1 to 1
4)
10 to 1
4)
10 to 1
For steam service, the valve recognized as the best is the?
1)
Solid wedge gate valve
2)
Globe valve
3)
Gate valve
4)
Ball valve
1)
Solid wedge gate valve
What is the principle behind the working of hydraulic systems?
1)
Pascal’s law
2)
Newton’s third law
3)
Archimedes’ principle
4)
Bernoulli’s principle
1)
Pascal’s law
Which component in a hydraulic system converts hydraulic energy into mechanical energy?
1)
Pump
2)
Actuator
3)
Reservoir
4)
Filter
2)
Actuator
What is cavitation in a hydraulic system?
1)
The formation of bubbles in the hydraulic fluid
2)
The cleaning of hydraulic fluid
3)
The process of pressurizing hydraulic fluid
4)
The conversion of hydraulic energy
1)
The formation of bubbles in the hydraulic fluid
When cut grooving steel pipe for a hydraulic system what is the minimum
wall thickness of pipe required?
1)
Schedule 10.
2)
Schedule 40
3)
Schedule 80
4)
Schedule 160
3)
Schedule 80
Which type of hydraulic control valve can vary the flow rate proportional to an input signal?
1)
Directional control valve
2)
Pressure relief valve
3)
Proportional valve
4)
Check valve
3)
Proportional valve
What is the role of a sequence valve in a hydraulic system?
1)
To filter contaminants
2)
To maintain a set pressure
3)
To ensure operations occur in a specific sequence
4)
To store hydraulic fluid
3)
To ensure operations occur in a specific sequence
The term “prime mover” refers to the?
1)
Power source which drives the pump
2)
Input component of a hydraulic system
3)
Output component of a hydraulic system
4)
Actuator of a hydraulic system
1)
Power source which drives the pump
A spring-centered directional control valve has how many position(s)?
1)
One
2)
Two
3)
Three
4)
Four
3)
Three
A linear or rotary device used to convert fluid power into mechanical motion and force would be a good definition of?
1)
Pump
2)
Motor
3)
Piston
4)
Actuator
4)
Actuator
A fixed displacement pump has?
1)
Varying flow rates at a constant pump speed
2)
Varying pump speeds at a constant flow rate
3)
A constant flow rate at a constant pump speed
4)
Varying volume, pressure, and temperature capacity
3)
A constant flow rate at a constant pump speed
“Pressure” is defined as?
1)
A force moving through a distance
2)
A force moving through a distance in a given time
3)
A force acting over a given area
4)
A force applied to a load
3)
A force acting over a given area
What is the most effective method for removing deposits from a valve?
1)
Using a hammer
2)
Applying a solvent
3)
Using compressed air
4)
Heating the valve
2)
Applying a solvent
How often should regular valve inspections be conducted in a high-use system?
1)
Annually
2)
Monthly
3)
Weekly
4)
Daily
2)
Monthly
What material is commonly used for valve seats in high-temperature applications?
1)
Plastic
2)
Rubber
3)
Metal
4)
Teflon
3)
Metal
Which standard is commonly used for valve testing in the oil and gas industry?
1)
ASME B16
2)
API 598
3)
ISO 9001
4)
ASTM D2000
2)
API 598
What is the purpose of a backseat test in a valve?
1)
To ensure proper flow direction
2)
To check the integrity of the stem seal
3)
To evaluate the actuator performance
4)
To test the valve’s pressure rating
2)
To check the integrity of the stem seal
Which material is commonly used for constructing test manifolds in high-pressure applications?
1)
Plastic
2)
Aluminum
3)
Stainless steel
4)
Carbon Steel
3)
Stainless steel
What type of valve is commonly used in test manifolds for precise flow control?
1)
Ball valve
2)
Globe valve
3)
Needle valve
4)
Gate valve
3)
Needle valve
