B12 Flashcards
Why is direct burial of unprotected plastic-lined steel pipes not recommended?
A) It could lead to corrosion and damage to the pipe.
B) The pipes may overheat.
C) It is difficult to install without machinery.
D) It is too expensive.
It could lead to corrosion and damage to the pipe.
What type of material should be used for backfilling around buried plastic-lined pipes?
A) Gravel and sand mixture
B) Clean sand with no rocks or foreign material
C) Any soil available
D) Concrete
Clean sand with no rocks or foreign material
What is the typical flow velocity limit for liquids in plastic-lined piping to minimize pressure drop?
A. Less than 6 ft/sec (1.8 m/sec)
B. Less than 12 ft/sec (3.7 m/sec)
C. Less than 24 ft/sec (7.3 m/sec)
D. Less than 35 ft/sec (10.7 m/sec)
Less than 12 ft/sec (3.7 m/sec)
What is the most commonly available size range for corrosion-resistant lined pipes?
A. NPS 1 to 8 (DN 25 to 200)
B. NPS 1 to 12 (DN 25 to 300)
C. NPS 6 to 24 (DN 150 to 600)
D. NPS 12 to 24 (DN 300 to 600)
NPS 1 to 12 (DN 25 to 300)
Why should plastic-lined piping not be used below its recommended minimum operating temperature?
A. The liners will melt and degrade.
B. The liners can swell and react with the chemical media.
C. The liners can become brittle and fail mechanically.
D. The liners will release harmful gases.
The liners can become brittle and fail mechanically.
What should the piping-design engineer consider first when selecting a liner material?
A. Manufacturer reputation
B. Chemical resistance charts
C. Service conditions, including chemicals, concentration, and temperature
D. Cost of the liner material
Service conditions, including chemicals, concentration, and temperature
What is the primary benefit of plastic-lined metallic piping compared to corrosion-resistant metal piping?
A. Lower installation complexity
B. Superior resistance to chemical attack in all cases
C. Lower installed cost for flanged systems
D. Easier fabrication at the job site
Lower installed cost for flanged systems
Why is a plastic-lined metallic piping system preferred over solid-plastic piping systems?
A. Wider range of line sizes and fittings
B. Lower material cost
C. Simpler installation techniques
D. Reduced chemical resistance
Wider range of line sizes and fittings
What is one limitation of evaluating materials solely based on material costs?
A. It ignores factors like liner thickness.
B. It overlooks in-place costs, including fabrication and installation.
C. It does not consider chemical resistance.
D. It assumes all materials have equal service capabilities.
It overlooks in-place costs, including fabrication and installation.
What property of fluorinated plastics provides outstanding resistance to chemical attack?
A. High abrasion resistance
B. Fluorine-carbon bonding
C. Cold weather impact strength
D. Low coefficients of friction
Fluorine-carbon bonding
Which of the following fluorinated plastics has the highest temperature-handling capability?
A. PTFE
B. FEP
C. PFA
D. ETFE
PTFE
Which liner type is known to be virtually inert to most chemicals and was originally developed by DuPont in 1938?
A. PFA
B. FEP
C. PTFE
D. PVDC
PTFE
Which fluorinated plastic was the first melt-processible resin with chemical resistance comparable to PTFE?
A. FEP
B. PFA
C. ETFE
D. PP
FEP
What is a general characteristic of nonfluorinated plastics like polypropylene (PP) and polyvinylidene chloride (PVDC)?
A. Higher temperature resistance than fluoropolymers
B. More expensive than fluoropolymers
C. Good overall chemical resistance but lower than fluoropolymers
D. Higher thermal stability compared to fluorinated plastics
Good overall chemical resistance but lower than fluoropolymers
What is the purpose of the electrostatic test conducted on plastic-lined pipes?
A. To check for the proper sealing surface of the liner
B. To ensure the liner does not contain any defects
C. To test the chemical compatibility of the liner
D. To verify the pipe size and liner type
To ensure the liner does not contain any defects
What indicates the presence of a defect in the liner during the electrostatic test?
A. A change in voltage
B. A visible or audible spark at the probe
C. A decrease in pressure
D. Discoloration of the liner
A visible or audible spark at the probe
Fluorinated plastic lining materials include which of the following?
A. Polypropylene (PP)
B. Polytetrafluoroethylene (PTFE)
C. Polyethylene (PE)
D. Nylon
Polytetrafluoroethylene (PTFE)
What is the primary purpose of thermoplastic spacers?
A. To provide additional flexibility to the pipe
B. To connect plastic-lined pipes to dissimilar materials while forming a seal
C. To act as a replacement for gaskets
D. To reduce the wall thickness of lined pipes
To connect plastic-lined pipes to dissimilar materials while forming a seal
Which of the following thermoplastics is NOT mentioned as a widely used liner material?
A. Polypropylene (PP)
B. Polyvinylidene fluoride (PVDF)
C. Polytetrafluoroethylene (PTFE)
D. Polyethylene (PE)
Polyethylene (PE)
What is the primary challenge addressed by pipe lining techniques?
A. Ensuring that the liner and metal housing expand and contract as one.
B. Preventing shrinkage during sintering.
C. Controlling the wall thickness of PTFE tubes.
D. Reducing void content in PTFE liners.
Ensuring that the liner and metal housing expand and contract as one.
What is the primary purpose of the sintering process in PTFE production?
A. To melt the PTFE resin completely for molding.
B. To compact the resin for easier handling.
C. To coalesce polymer particles into a strong homogeneous structure.
D. To cool the PTFE to achieve crystallinity development.
To coalesce polymer particles into a strong homogeneous structure.
What should be done with protective end covers on plastic-lined pipe and fittings?
A. They should be removed immediately upon delivery.
B. They should be left on until just before installation.
C. They should be discarded after inspection.
D. They should be reused for other materials.
They should be left on until just before installation.
What is the purpose of using a calibrated torque wrench during installation?
A. To ensure bolts are tightened to the maximum torque.
B. To avoid excess torque that can damage the plastic flare faces.
C. To speed up the installation process.
D. To measure the weight of the fittings.
To avoid excess torque that can damage the plastic flare faces.
How should bolts be tightened on a flange connection?
A. In a circular pattern.
B. In a star pattern.
C. Randomly to save time.
D. Only the top bolts should be tightened.
In a star pattern.
What should be done after the first thermal cycle of the bolted connection?
A. All bolts should be replaced.
B. All bolts should be checked and retorqued if necessary.
C. The connection should be completely disassembled.
D. No action is required.
All bolts should be checked and retorqued if necessary.
Why are gaskets not required for connections of lined pipe to other lined pipe?
A. The plastic liner serves as its own gasket.
B. Gaskets are always required for all connections.
C. Lined pipes do not have flanges.
D. Gaskets are too expensive for lined pipes.
The plastic liner serves as its own gasket.
When are gaskets recommended for lined pipe connections?
A. When connecting lined pipe to another lined pipe.
B. When bolting lined pipe to an unlined raised-face flange.
C. When using plastic-lined pipe only.
D. When the temperature is below freezing.
When bolting lined pipe to an unlined raised-face flange.
What should be considered for hanger spacing when installing plastic-lined piping?
A. It should be different from carbon steel piping.
B. It is essentially the same as recommended for carbon steel piping.
C. Hanger spacing is not important.
D. Hangers should be placed every foot.
It is essentially the same as recommended for carbon steel piping.
What is recommended for supporting each spool of plastic-lined pipe?
A. Support should be near the flange connection.
B. No support is needed.
C. Support should be at the midpoint of the pipe.
D. Only one support is needed for long spans.
Support should be near the flange connection.
What is a method to compensate for thermal expansion in piping systems?
A. Using expansion loops
B. Increasing pipe diameter
C. Reducing fluid temperature
D. Welding joints
Using expansion loops
Why should welding not be performed on plastic-lined pipe?
A. It can create leaks
B. It can severely damage the liner
C. It weakens the pipe structure
D. It is not allowed by law
It can severely damage the liner
Which of the following is NOT a method used for heat tracing plastic-lined pipe?
A. Hot water
B. Electrical resistance
C. Steam
D. Cold water
Cold water
What is a key consideration when selecting a heat tracing method for plastic-lined pipe?
A. Color of the pipe
B. Temperature rating of the plastic liner
C. Length of the pipe only
D. Cost of the pipe material
Temperature rating of the plastic liner
What is the primary purpose of placing the temperature-controller sensing device in direct contact with the heating strip or cable?
A. To increase the heating efficiency
B. To ensure maximum operating temperature is not exceeded
C. To reduce the cost of materials
D. To simplify the installation process
To ensure maximum operating temperature is not exceeded
What is typically used as the heating fluid in jacketed-lined pipe systems?
A. Air
B. Water, steam, or heat transfer fluid
C. Oil
D. Liquid nitrogen
Water, steam, or heat transfer fluid
Why is grounding of piping systems necessary?
A. To improve fluid flow
B. To prevent spark generation from static electrical charge
C. To enhance thermal insulation
D. To reduce corrosion
To prevent spark generation from static electrical charge
What is a common technique used to ensure adequate grounding in piping systems?
A. Using plastic fittings
B. Welding stud bolts to the pipe shell
C. Applying heat transfer cement
D. Using non-conductive materials
Welding stud bolts to the pipe shell
What is the primary reason metals corrode?
A. They are exposed to sunlight
B. Electrochemical reactions
C. They are too thick
D. They are painted
Electrochemical reactions
What happens to plastics when they are attacked by solvation?
A. They corrode like metals
B. They become completely resistant
C. They swell or crack
D. They become stronger
They swell or crack
What should be done if a flange leak occurs during a hydrotest?
A. Tighten the leaking side bolts further
B. Loosen bolts on the opposite side and tighten leaking side bolts
C. Remove the flange immediately
D. Ignore the leak
Loosen bolts on the opposite side and tighten leaking side bolts
What type of test is required to check for defects in the liner material according to ASTM?
A. Hydrostatic Test
B. Electrostatic Test
C. Visual Inspection
D. Ultrasonic Test
Electrostatic Test
What is the purpose of the High and Low-Temperature Aging Test?
A. To determine the ability of the lined component to withstand extended exposure to temperature extremes
B. To test the chemical resistance of the liner material
C. To evaluate the pressure handling capability of the lined component
D. To assess the flexibility of the liner material
To determine the ability of the lined component to withstand extended exposure to temperature extremes
Which of the following must be included in a piping specification?
A. Employee training programs
B. Maximum pressure and temperature ratings
C. Company financial status
D. Marketing analysis
Maximum pressure and temperature ratings
What should be referenced to ensure material compliance in piping specifications?
A. ISO standards
B. ASTM standards
C. Local building codes
D. Environmental regulations
ASTM standards
What is a common reason for piping component failure?
A. Exceeding design capabilities
B. Using outdated materials
C. Improper installation techniques
D. Lack of maintenance
Exceeding design capabilities
What information should be provided to assist the designer in laying out the pipe?
A. Company history
B. Maximum and minimum lengths available
C. Employee roles
D. Budget constraints
Maximum and minimum lengths available
What is the primary objective of improving mechanical integrity standards in process piping?
A. To increase the aesthetic appeal of piping systems
B. To eliminate piping and equipment-related incidents
C. To reduce the cost of materials
D. To enhance the speed of installation
To eliminate piping and equipment-related incidents
What is a key factor in a good maintenance program for piping systems?
A. Regular painting of pipes
B. Proper documentation of installation and maintenance
C. Frequent replacement of all piping
D. Using only metal piping
Proper documentation of installation and maintenance
Which technique is used to locate liner collapse in piping systems?
A. Visual inspection
B. Ultrasonic techniques
C. Chemical testing
D. Magnetic resonance imaging
Ultrasonic techniques
What can cause liner failure in plastic-lined piping?
A. Low temperatures
B. Excessive fluid loading
C. Infrequent inspections
D. Use of metal components
Excessive fluid loading
What is the recommended practice for inspecting piping systems at night?
A. Visual inspection
B. Infrared inspection
C. Ultrasonic inspection
D. Chemical analysis
Infrared inspection
What can be a consequence of high-temperature operation in plastic-lined piping?
A. Increased durability
B. Decreased service life
C. No effect on service life
D. Improved flow rates
Decreased service life
