A6 Flashcards
What does the term “fabrication” primarily refer to in piping systems?
A. Physical placement of subassemblies
B. Cutting, bending, forming, and welding of components
C. Final NDE and leak testing
D. Cleaning and flushing of piping systems
Cutting, bending, forming, and welding of components
Why are commercial pipe fabrication shops often preferred over site fabrication shops?
A. They are closer to installation sites
B. They employ more workers
C. They have specialized equipment and higher efficiency
D. They do not require heat treatment
They have specialized equipment and higher efficiency
For which pipe size is shop fabrication most commonly used in industrial applications?
A. NPS 1 (DN 25) C. NPS 2 ½ (DN 65) and larger
B. NPS 2 (DN 50) D. NPS 1 ½ (DN 40)
NPS 2 ½ (DN 65) and larger
What additional processes are included during the installation phase of piping systems?
A. Welding, final NDE, leak testing, and flushing
B. Cutting and forming of pipe components
C. Heat treatment and bending
D. Non-metallic pipe fabrication
Welding, final NDE, leak testing, and flushing
Why is it essential for fabrication and installation contractors to work closely with designers?
A. To reduce project costs
B. To ensure compliance with codes and address material limitations
C. To accelerate the installation timeline
D. To avoid the use of special alloys
To ensure compliance with codes and address material limitations
What must purchase specifications for piping materials and fabrication reflect to ensure proper practices are used?
A. The general recommendations of the applicable code
B. The specific requirements for material grade, product form, and heat treatment
C. The cost-saving practices recommended by the installer
D. Only the maximum allowable stress levels
The specific requirements for material grade, product form, and heat treatment
Which organization publishes Engineering Standards that provide guidance for many fabrication processes not covered by codes?
A. ASME
B. American Petroleum Institute (API)
C. Pipe Fabrication Institute (PFI)
D. Manufacturers Standardization Society (MSS)
Pipe Fabrication Institute (PFI)
Why heat treatment necessary after hot bending certain austenitic stainless steels?
A. To increase the material’s tensile strength
B. To improve weldability
C. To restore corrosion resistance lost during bending
D. To reduce the material’s thermal expansion coefficient
To restore corrosion resistance lost during bending
What is the primary purpose of installation drawings in piping systems?
A. To outline the materials required for pipe fabrication
B. To prepare detailed welding procedures
C. To specify plans, sections, and requirements for fabrication and installation
D. To determine the shipping requirements for pipe spools
To specify plans, sections, and requirements for fabrication and installation
What factors influence the division of a prefabricated piping system into subassemblies or spools?
A. Corrosion resistance and weldability of the materials
B. Dimensional and weight limitations for shipping and heat treatment
C. Field clearance requirements and valve tolerances
D. Sensitization range and allowable stress limits
Dimensional and weight limitations for shipping and heat treatment
What can “tolerance stack-up” in a piping system affect?
A. The weight distribution of the piping system
B. The overall dimensions of the system, especially in closely coupled systems
C. The weld quality of field joints
D. The selection of appropriate heat treatment methods
The overall dimensions of the system, especially in closely coupled systems
Why is oxyfuel gas cutting not effective for higher alloy materials?
A. It requires additional preheating
B. The cutting temperature is too low for these materials
C. The chemical reaction becomes inefficient with increasing alloy content
D. The process damages the material’s corrosion resistance
The chemical reaction becomes inefficient with increasing alloy content
Which process is commonly used for cutting higher alloy materials?
A. Oxyfuel gas cutting C. Mechanical cutting with saws
B. Plasma arc cutting D. Lapping and swaging
Plasma arc cutting
What is the main factor that might dictate the use of forming operations like bending and swaging in pipe fabrication?
A. The availability of welding fittings
B. The complexity of welding procedures
C. Economic considerations and special pipe sizes
D. The need for third-party inspection
Economic considerations and special pipe sizes
Which bending method is commonly used for coiling pipes and offers flexibility in choosing bending radii?
A. Compression bending C. Rotary draw bending
B. Ram bending D. Roll bending
Roll bending
Why is sand filling recommended for pipes with a diameter-to-thickness ratio of 10:1 or greater during hot bending?
A. To provide thermal insulation during heating
B. To reduce the chance of buckling by increasing rigidity
C. To achieve a smaller bending radius
D. To reduce the temperature required for bending
To reduce the chance of buckling by increasing rigidity
What is the key characteristic of the increment bending process?
A. It heats the entire pipe evenly throughout the process
B. It involves heating and bending in small sections sequentially
C. It is limited to pipes with a maximum diameter of NPS 10
D. It requires the use of roll bending machines
It involves heating and bending in small sections sequentially
What is the maximum wall thickness that can be bent using the induction bending process?
A. 2 inches (50 mm) C. 4 inches (100 mm)
B. 3 inches (75 mm) D. 5 inches (125 mm)
4 inches (100 mm)
Why is an internal mandrel often required when draw bending copper pipes?
A. To maintain the required bending temperature
B. To reduce the risk of buckling and ensure dimensional accuracy
C. To heat the pipe evenly during the process
D. To prevent thinning of the extrados
To reduce the risk of buckling and ensure dimensional accuracy
What forming operation involves reducing the size of pipe ends by forging, pressing, or rolling?
A. Extrusion C. Lapping
B. Swaging D. Heat treating
Swaging
What is essential to do before assembling piping subassemblies for welding?
A. Preheat the entire pipe to forging temperature
B. Clean weld surfaces of rust, scale, grease, and foreign substances
C. Perform a post-bending heat treatment
D. Increase the wall thickness of the pipe by 30%
Clean weld surfaces of rust, scale, grease, and foreign substances
What is the main advantage of Submerged Arc Welding (SAW)?
A. Ability to weld in all positions
B. Highest deposition rate among welding processes
C. Minimal interpass temperature control required
D. Effective for root pass welding without backing
Highest deposition rate among welding processes
Which welding process uses a non-consumable tungsten electrode and requires filler metal from an external source?
A. Shielded Metal Arc Welding (SMAW)
B. Submerged Arc Welding (SAW)
C. Gas Tungsten Arc Welding (GTAW)
D. Gas Metal Arc Welding (GMAW)
Gas Tungsten Arc Welding (GTAW)
Which welding process is considered most desirable for making root welds of the highest quality?
A. SMAW (Shielded Metal Arc Welding)
B. SAW (Submerged Arc Welding)
C. GTAW (Gas Tungsten Arc Welding)
D. FCAW (Flux Core Arc Welding)
GTAW (Gas Tungsten Arc Welding)