Book 7 Flashcards
In most sizes of pipe, Schedule 40 corresponds to _____ wall thickness.
Select one:
a.
Welded only
b.
Threaded only
c.
Extra strong (XS)
d.
Standard
Standard
Up to and including DN 300 mm pipe, the “nominal pipe size” refers to a pipe’s
Select one:
a.
nominal circumference
b.
nominal inside diameter
c.
nominal outside diameter
d.
nominal wall thickness
nominal inside diameter
The purpose of a steam separator is to remove _____ from the steam.
Select one:
a.
Oil
b.
Moisture
c.
Impurities
d.
Non-condensable gases
Moisture
The piping service symbols “A”, “G”, “O” stand for:
Select one:
a.
Acetylene, gasoline, and oil
b.
Air, gaseous and oil
c.
Air, gases and oxygen
d.
Ammonia, gaseous and octane
Air, gaseous and oil
In piping systems, the three main types of flange gaskets are the full face, the ring joint, and the:
Select one:
a.
Corrugated Bellows type
b.
Van Stone type
c.
Flat ring type
d.
Segmental ring type
Flat ring type
In order to ensure safe and continuous operation of a pressure reducing valve, the valve station should have _________________.
Select one:
a.
A safety valve on the high-pressure side
b.
A bypass line, plus a safety valve and pressure gauge on the low-pressure side
c.
Thermometers on the inlet and outlet piping
d.
A strainer immediately downstream of the valve
A bypass line, plus a safety valve and pressure gauge on the low-pressure side
The biggest advantage of an outside screw and yoke, rising stem valve over other designs is that it is_________.
Select one:
a.
Inexpensive
b.
Stronger in construction
c.
More durable
d.
Easy to see whether the valve is open or closed
Easy to see whether the valve is open or closed
A frequent cause of serious accidents with valves is __________________.
Select one:
a.
improperly sized valves leading to flow problems
b.
lack of maintenance
c.
inadequate operational training leading to abuse
d.
unsuitable materials for the operating pressures and temperatures
unsuitable materials for the operating pressures and temperatures
A common material used for water and instrument air piping in power plants is
Select one:
a.
galvanized steel
b.
cast iron
c.
bronze
d.
copper
copper
What does ASME B31.1 recommend for boiler discharge stop valves?
a.
It recommends they be used with a wheel and motor attached to the stem
b.
It recommends they have an outside screw and yoke with a rising spindle
c.
It recommends having a power actuator to position the disc
d.
It recommends they have an outside screw and yoke with a non-rising spindle
It recommends they have an outside screw and yoke with a rising spindle
What kinds of damage occur on the valve seat?
a.
Grooving and wire drawing
b.
Stretching and shrinking
c.
Grinding and chipping
d.
Scaling and pitting
Grooving and wire drawing
The most common material for power plant piping is:
Select one:
a.
Alloyed nonferrous
b.
Forged cast
c.
Steel
d.
Plastic and ABS
Feedback
Steel
Which of these valve components is NOT considered to be part of “valve trim”?
Select one:
a.
Disc
b.
Seat ring
c.
Body
d.
Valve stem
e.
Packing gland
Body
The main purpose of insulation on piping systems is to:
Select one:
a.
Reduce heat transfer between the pipe and its surroundings
b.
Allow for the application of line identifier stickers and flow arrows
c.
Provide a paint surface
d.
Prevent condensate from evaporating in the lines
Reduce heat transfer between the pipe and its surroundings
Which of the following is NOT one of the three general methods used to join or connect lengths of pressure piping?
a.
Threaded pipe and screwed connections
b.
Flanges
c.
Brazed joints
d.
Welded joints
Brazed joints
Welding together pipes that are 2 inch nominal size or smaller is usually done using:
Select one:
a.
The oxy-acetylene method
b.
The socket weld method
c.
The butt weld method
d.
Automatic welding machines
The socket weld method
The valve design with the greatest capability to handle slurries and fluids with high suspended solids is the __________ valve.
Select one:
a.
Globe
b.
Gate
c.
Ball
d.
Needle
Ball
Cast iron pipe has a high resistance to:
Select one:
a.
Water pressure
b.
Impacts
c.
Temperature changes
d.
Corrosion
Corrosion
Improper drainage of steam lines could cause:
Select one:
a.
Excessive steam pressures
b.
Low pressure in the lines
c.
Water hammer
d.
Excessive weight to the pipe
Water hammer
Valves that are not clearly identified should be _______________.
Select one:
a.
Used only with water systems
b.
Stamped with a CRN
c.
Rejected
d.
Approved for use by the boiler inspector
Rejected
Gaskets are installed between pipe flanges to:
Select one:
a.
Prevent leakage due imperfections in the flange face
b.
Allow pipe expansion between flange joints
c.
Account for misalignment of the pipe
d.
Provide cushioning against water hammer
Prevent leakage due imperfections in the flange face
The service designation of a pipe fitting indicates _____________________.
Select one:
a.
the location where the valve was manufactured
b.
the Canadian Registration Number for the valve
c.
the temperature-pressure rating of the valve
d.
the seat and packing material designation
the temperature-pressure rating of the valve
Of these materials, the one most commonly used for sewage piping is
Select one:
a.
stainless steel
b.
cast steel
c.
cast iron
d.
aluminum
cast iron
What does valve trim consist of?
a.
Disc, wheel, guide bushings
b.
Disc, wheel, gland packing
c.
Disc, seat ring, stuffing box
d.
Disc, seat ring, guide bushings
Disc, seat ring, guide bushings
The __________ valve requires specific and routine lubrication.
Select one:
a.
Butterfly
b.
Globe
c.
Check
d.
Tapered plug
Tapered plug
The wall thickness of steel pipe is designated by its _____________.
Select one:
a.
Schedule number
b.
CRN number
c.
Diameter
d.
Material strength number
Schedule number
A common material used for valve packing is ____________________.
Select one:
a.
Fiberglass
b.
Mica
c.
Nylon
d.
Teflon
Teflon
Foamed plastics are generally used in which low and lower intermediate service temperature range?
a.
150°C to 183°C
b.
155°C to 183°C
c.
150°C to 185°C
d.
155°C to 185°C
150°C to 183°C
The mass of a 2 m length of Schedule 40 pipe, outside diameter 101.6 mm, is:
Select one:
a.
36.98 kg
b.
31.9 kg
c.
26.92 kg
d.
11.48 kg
26.92 kg
A slip type expansion joint:
Select one:
a.
requires no maintenance
b.
is suitable only for low pressures and temperatures
c.
requires lubrication
d.
will adjust for misalignment of lines
requires lubrication
Pipe insulation, when installed on pipes that carry cold fluids, prevents
Select one:
a.
The requirements for heat tracing
b.
Water hammer at elbows
c.
Expansion and contraction
d.
Sweating and corrosion
Sweating and corrosion
The bypass around a regulating valve should contain a ___________ valve.
Select one:
a.
gate
b.
needle
c.
globe
d.
butterfly
globe
The purpose of a steam trap is to:
Select one:
a.
Collect steam for storage purposes
b.
Reduce the steam pressure in a line
c.
Remove condensate from steam lines without allowing steam to escape
d.
Remove steam from a steam line without allowing water to pass
Remove condensate from steam lines without allowing steam to escape
The valve that is least susceptible to wire drawing and seat erosion is the _________ valve.
Select one:
a.
Globe
b.
Gate
c.
Plug
d.
Wedge gate
Globe
A Van Stone flange is fitted ___________ on a pipe:
Select one:
a.
with tack welds
b.
using coarse threads
c.
loosely
d.
with evenly spaced set screws
loosely
A typical application of forged steel in a power plant is:
Select one:
a.
welded pipe fittings
b.
superheated steam lines
c.
drain lines
d.
ash handling systems
welded pipe fittings
A bellows corrugated expansion joint is suitable for pressures up to approximately _______ kPa:
Select one:
a.
500
b.
1000
c.
2000
d.
Unlimited
2000
The inside diameter of a pipe is expressed as the:
Select one:
a.
Pipe size plus wall roughness
b.
Nominal pipe size
c.
Formula 2P-M=k
d.
Outside diameter minus twice the wall thickness
Nominal pipe size
________ provide easy assembly and dismantling of screwed piping connections.
Select one:
a.
Couplings
b.
Flanges
c.
Unions
d.
Bolts
Unions
The three markings mandatory on valves to be used in pressure piping include manufacturer’s name, material designation and _______________.
Select one:
a.
weight designation
b.
CRN number
c.
valve type
d.
service designation
service designation
With respect to NPS 14 pipe and larger, as the wall thickness is increased, the:
Select one:
a.
Inside diameter is reduced
b.
Outside diameter increases
c.
Weight of the pipe decreases
d.
Bore of the pipe increases
Inside diameter is reduced
To extend the life of valve packing, we can___________________.
Select one:
a.
Operate the valve at lower temperatures
b.
Lubricate the valve stem with oil
c.
Operate the valve slowly
d.
Operate the valve on a regular basis
Lubricate the valve stem with oil
When tightening the bolts on a pipe flange:
Select one:
a.
Tighten every second bolt first, then tighten the others
b.
The gasket should be held in place by gasket glue
c.
The top bolts must be tightened first
d.
Use a sequential criss-cross method of tightening
Use a sequential criss-cross method of tightening
Materials used for the manufacture of pipes for power plants MUST be:
Select one:
a.
Manufactured only in Canada
b.
Seamless regardless of the operating conditions
c.
Suitable for the system operating conditions
d.
Welded and stress relieved
Suitable for the system operating conditions
One disadvantage of using threaded connections to join pipes and fittings is that it:
Select one:
a.
Is more costly
b.
Weakens the pipe
c.
Difficult to insulate
d.
Requires the services of a pipe fitter
Weakens the pipe
The purpose of the non-return valve on a boiler is to_____________________.
Select one:
a.
Prevent water from entering the steam header
b.
Prevent the back flow of steam into the boiler
c.
Prevent the safety valve from popping
d.
Regulate the flow of steam from the boiler
Prevent the back flow of steam into the boiler
Pipe nipples are _____ on both ends.
Select one:
a.
Welded
b.
Threaded
c.
Closed
d.
Flanged
Threaded
Low pressure steam pipes are commonly joined together by:
Select one:
a.
Welding
b.
Screwed fittings
c.
Reducing bushings
d.
16 Bolt flanges
Screwed fittings
Expansion of piping is controlled by:
Select one:
a.
Anchoring the pipe at both ends to prevent movement
b.
Installing an expansion joint in the line
c.
Preheating the pipe prior to installation
d.
Installing spring supports on the pipe
Installing an expansion joint in the line
A steam trap should be installed below the _______ point in piping system it serves.
Select one:
a.
Coldest
b.
Hottest
c.
Highest
d.
Lowest
Lowest
The material designation marking on a valve __________________.
Select one:
a.
indicates which manufacturing branch it originates from
b.
indicates the material that the valve is made from
c.
gives the maximum temperature for the valve material
d.
is associated with the Canadian Registration Number
indicates the material that the valve is made from
White cast iron has a high resistance to corrosion and abrasion, which makes it useful for:
Select one:
a.
Underground steam lines
b.
Ash handling systems
c.
Condensate lines
d.
Natural gas supply lines
Ash handling systems
Increasing the spring tension in a pressure reducing valve will ___________________.
Select one:
a.
Reduce or minimize the cycling or “hunting” of the valve
b.
Decrease the regulated pressure downstream of the valve
c.
Allow for maintenance to be completed downstream
d.
Increase the regulated pressure downstream of the valve
Increase the regulated pressure downstream of the valve
An advantage of expansion bends is that they are __________ than expansion joints.
Select one:
a.
stronger
b.
easier to service
c.
heavier
d.
more compact
stronger
When admitting steam to a steam piping system it is imperative to:
Select one:
a.
Use the glycol tracing to warm the line.
b.
First ensure that no water exists or can accumulate in the piping.
c.
Ensure drain valves are closed to prevent steam loss.
d.
Add nitrogen to steam to prevent corrosion.
First ensure that no water exists or can accumulate in the piping.
A check valve____________________.
Select one:
a.
Allows flow in one direction only.
b.
Uses a heavy spring for setting.
c.
Requires an inspector’s seal to be installed.
d.
Has a locking spindle for locking out flow for safety.
Allows flow in one direction only.
With respect to NPS 14 pipe and larger, the Nominal Pipe Size number is referring to the:
Select one:
a.
Outside diameter
b.
Inside diameter
c.
Thickness
d.
Mass per metre of length
Outside diameter
Two main categories of manufactured steel piping are
Select one:
a.
Seamless and welded
b.
Welded or screwed
c.
Piping and tubing
d.
Pressure and water
Seamless and welded
_______ fittings are used to provide proper drainage of water.
Select one:
a.
Removable
b.
Orifice
c.
Eccentric
d.
Tapered
Eccentric
A thermostatic steam trap is controlled by the:
Select one:
a.
Difference in velocity between condensate and steam
b.
Air pressure built up on top of disk
c.
Temperature difference between condensate and steam
d.
Bucket, which flips when filled with condensate
Temperature difference between condensate and steam
With respect to NPS 14 pipe and larger, as the pipe schedule increases, the outside diameter:
Select one:
a.
Dependent on the material selected
b.
Remains the same
c.
Decreases
d.
Will be equal to the schedule number
Remains the same
A _________ should be installed just ahead of a steam trap.
Select one:
a.
Check valve
b.
Throttling valve
c.
Pressure reducing valve
d.
Sediment separator or strainer
Sediment separator or strainer
The three general types of flange connections are the screwed, the Van Stone and the _____ .
Select one:
a.
Bolted
b.
Ring joint
c.
Raised face
d.
Welded
Welded
Which gasket has an oval cross-section?
Select one:
a.
Flat ring
b.
Full face
c.
Cut asbestos
d.
Ring joint
Ring joint
Which two systems are used to designate nominal pipe size?
a.
USCS uses NPS, and SI assigns a DN
b.
Nominal inside diameter and actual outside diameter
c.
Schedule numbers and nominal size
d.
SI uses NPS and USCS assigns a DN
USCS uses NPS, and SI assigns a DN
Valve components that require regular inspection are the _____________.
Select one:
a.
disc and seat
b.
stem and body
c.
stuffing box and spindle threads
d.
hand wheel and packing
disc and seat
Steam traps may also remove _______ from steam lines.
Select one:
a.
Oil
b.
Superheat
c.
Chemicals
d.
Air
Air
A good rule of thumb is to install pipe hangers at ___________ intervals along a pipe.
Select one:
a.
1 m
b.
1.5 m
c.
3 m
d.
5 m
3 m
_____________ are used to connect pipes of the same diameter, creating a straight run of pipe.
Select one:
a.
Nipples
b.
Couplings
c.
Bushings
d.
Elbows
Couplings
The maximum operating temperature for a carbon steel valve is _________ °C:
Select one:
a.
280
b.
425
c.
650
d.
1000
425
Plastic foam pipe insulation is:
Select one:
a.
Used for high temperature service on elbows
b.
Used for refrigeration piping only
c.
Used for lower temperature purposes
d.
Often installed by the welders
Used for lower temperature purposes
When butt welding pipe, a backing ring is used to:
Select one:
a.
Reinforce the pipe joint
b.
Align the pipe
c.
Prevent welding gases from entering the pipe line
d.
Reduce the amount of welding rod required
Align the pipe
Which valve is installed by sliding it between two flanges in the piping?
a.
Gate
b.
Butterfly
c.
Globe
d.
Needle
Butterfly
A mechanical steam trap:
Select one:
a.
Can be fitted in any position
b.
May have a thermostatic air release
c.
Has alcohol inside the float
d.
Requires a difference in steam temperatures to operate
May have a thermostatic air release
Two types of expansion joints are the _________ designs.
Select one:
a.
Bolted and threaded
b.
Flex bend and raised face
c.
Ring joint and slip
d.
Bellows and slip
Bellows and slip
Where is the strainer located in the pressure regulator of a steam pressure reducing station?
a.
Upstream of the regulator
b.
Downstream of the regulator
c.
Upstream of the steam separator
d.
On the sensing line feeding the regulator
Upstream of the regulator
Which type of steam trap is not suited for outdoor use?
a.
Ball trap
b.
Bellows
c.
Inverted bucket
d.
Thermostatic
Ball trap
What are the two types of expansion joints in general use?
a.
Slip and corrugated
b.
Expansion bend and corrugated
c.
Expansion bend and expansion joint
d.
Expansion bend and slip
Slip and corrugated
The bypass around a regulating valve should contain a ___________ valve.
Select one:
a.
gate
b.
needle
c.
globe
d.
butterfly
globe
Cast iron pipe has a high resistance to:
Select one:
a.
Water pressure
b.
Impacts
c.
Temperature changes
d.
Corrosion
Corrosion
With respect to NPS 14 pipe and larger, the Nominal Pipe Size number is referring to the:
Select one:
a.
Outside diameter
b.
Inside diameter
c.
Thickness
d.
Mass per metre of length
Outside diameter
With respect to NPS 14 pipe and larger, as the pipe schedule increases, the outside diameter:
Select one:
a.
Dependent on the material selected
b.
Remains the same
c.
Decreases
d.
Will be equal to the schedule number
Remains the same
The purpose of a steam trap is to:
Select one:
a.
Collect steam for storage purposes
b.
Reduce the steam pressure in a line
c.
Remove condensate from steam lines without allowing steam to escape
d.
Remove steam from a steam line without allowing water to pass
Remove condensate from steam lines without allowing steam to escape
The material designation marking on a valve __________________.
Select one:
a.
indicates which manufacturing branch it originates from
b.
indicates the material that the valve is made from
c.
gives the maximum temperature for the valve material
d.
is associated with the Canadian Registration Number
indicates the material that the valve is made from
Which gasket has an oval cross-section?
Select one:
a.
Flat ring
b.
Full face
c.
Cut asbestos
d.
Ring joint
Ring joint
The biggest advantage of an outside screw and yoke, rising stem valve over other designs is that it is_________.
Select one:
a.
Inexpensive
b.
Stronger in construction
c.
More durable
d.
Easy to see whether the valve is open or closed
Easy to see whether the valve is open or closed
The purpose of a steam separator is to remove _____ from the steam.
Select one:
a.
Oil
b.
Moisture
c.
Impurities
d.
Non-condensable gases
Moisture
A bellows corrugated expansion joint is suitable for pressures up to approximately _______ kPa:
Select one:
a.
500
b.
1000
c.
2000
d.
Unlimited
2000
The valve that is least susceptible to wire drawing and seat erosion is the _________ valve.
Select one:
a.
Globe
b.
Gate
c.
Plug
d.
Wedge gate
Globe
The three markings mandatory on valves to be used in pressure piping include manufacturer’s name, material designation and _______________.
Select one:
a.
weight designation
b.
CRN number
c.
valve type
d.
service designation
service designation
A common material used for valve packing is ____________________.
Select one:
a.
Fiberglass
b.
Mica
c.
Nylon
d.
Teflon
Teflon
A thermostatic steam trap is controlled by the:
Select one:
a.
Difference in velocity between condensate and steam
b.
Air pressure built up on top of disk
c.
Temperature difference between condensate and steam
d.
Bucket, which flips when filled with condensate
Temperature difference between condensate and steam
Which type of steam trap is not suited for outdoor use?
a.
Thermostatic
b.
Ball trap
c.
Inverted bucket
d.
Bellows
Ball trap
The purpose of the non-return valve on a boiler is to_____________________.
Select one:
a.
Prevent water from entering the steam header
b.
Prevent the back flow of steam into the boiler
c.
Prevent the safety valve from popping
d.
Regulate the flow of steam from the boiler
Prevent the back flow of steam into the boiler
The valve design with the greatest capability to handle slurries and fluids with high suspended solids is the __________ valve.
Select one:
a.
Globe
b.
Gate
c.
Ball
d.
Needle
Ball
A slip type expansion joint:
Select one:
a.
requires no maintenance
b.
is suitable only for low pressures and temperatures
c.
requires lubrication
d.
will adjust for misalignment of lines
requires lubrication
________ provide easy assembly and dismantling of screwed piping connections.
Select one:
a.
Couplings
b.
Flanges
c.
Unions
d.
Bolts
Unions
Improper drainage of steam lines could cause:
Select one:
a.
Excessive steam pressures
b.
Low pressure in the lines
c.
Water hammer
d.
Excessive weight to the pipe
Water hammer
A steam trap should be installed below the _______ point in piping system it serves.
Select one:
a.
Coldest
b.
Hottest
c.
Highest
d.
Lowest
Lowest
Increasing the spring tension in a pressure reducing valve will ___________________.
Select one:
a.
Reduce or minimize the cycling or “hunting” of the valve
b.
Decrease the regulated pressure downstream of the valve
c.
Allow for maintenance to be completed downstream
d.
Increase the regulated pressure downstream of the valve
Increase the regulated pressure downstream of the valve
