A3 Flashcards
What is the primary consideration in selecting materials for piping applications?
A. The ability to resist chemical reactions
B. Suitability for flow medium and operating conditions
C. Cost-effectiveness and availability
D. Compliance with environmental regulations
Suitability for flow medium and operating conditions
What operational variables must piping materials resist for long-term service?
A. Pressure and velocity fluctuations C. Temperature and corrosion
B. Thermal and mechanical cycling D. Creep and oxidation resistance
Thermal and mechanical cycling
Which factor related to the operating environment of the pipe is critical during material selection?
A. The weight of the surrounding structure
B. Degradation due to corrosion or erosion
C. Thermal conductivity of the surrounding material
D. Electrical conductivity of the pipe material
Degradation due to corrosion or erosion
Why is compliance with design and construction codes such as the ASME B31 Pressure Piping Code important?
A. It ensures economical material selection.
B. It specifies material degradation issues.
C. It assures safe operation under specified conditions.
D. It prevents oxidation and thermal cycling issues.
It assures safe operation under specified conditions
What is one limitation of designing piping systems strictly based on ‘the Code’?
A. It increases fabrication complexity.
B. It overlooks environmental and material degradation issues.
C. It prohibits the use of carbon and low alloy steels.
D. It ignores thermal and mechanical stresses.
It overlooks environmental and material degradation issues
What is the smallest repeating building block of a crystalline structure in metals called?
A. Space lattice C. Unit cell
B. Crystal lattice D. Atomic grid
Unit cell
Which two unit cell forms are observed in iron and iron-based alloys?
A. Hexagonal close-packed (HCP) and cubic lattice
B. Body-centered cubic (BCC) and face-centered cubic (FCC)
C. Tetragonal and orthorhombic structures
D. Body-centered tetragonal (BCT) and face-centered orthorhombic (FCO)
Body-centered cubic (BCC) and face-centered cubic (FCC)
What distinguishes the face-centered cubic (FCC) structure from the body-centered cubic (BCC) structure?
FCC has atoms at the cube corners and the center of each face
What is the fundamental atomic motion involved in plasticity?
A. Atoms vibrating in place within the lattice
B. Atoms sliding across planes in the crystal structure
C. Atoms rearranging to form new unit cells
D. Atoms breaking free from the lattice
Atoms sliding across planes in the crystal structure
What causes certain metals, such as iron, to change their crystal structure?
A. Variations in temperature C. Application of mechanical stress
B. Exposure to chemical reactions D. Changes in pressure
Variations in temperature
What is the main difference in the atomic structure of plastics compared to metals?
A. Plastics lack a predictable atomic structure.
B. Plastics are formed by carbon-hydrogen chains (monomers to polymers).
C. Plastics have a crystalline atomic structure similar to ceramics.
D. Plastics have no molecular weight.
Plastics are formed by carbon-hydrogen chains (monomers to polymers)
What is a key limitation of plastics compared to metals in engineering applications?
A. Higher impact strength
B. Poor chemical, thermal, and aging stability
C. Greater strength per unit weight
D. Limited versatility in construction
Poor chemical, thermal, and aging stability
How do ceramic materials differ from metals in terms of atomic behavior?
A. Ceramics have random atomic arrangements like glasses.
B. Ceramics exhibit more plasticity than metals.
C. Ceramics have rigid, predictable atomic structures but lack plasticity.
D. Ceramics are composed entirely of polymers.
Ceramics have rigid, predictable atomic structures but lack plasticity
Into which three categories do the properties of engineering materials fall?
A. Chemical, mechanical, and physical
B. Atomic, structural, and electronic
C. Structural, mechanical, and electrical
D. Thermal, electronic, and physical
Chemical, mechanical, and physical
What is the process of adding secondary elements to metals to improve or modify their behavior called?
A. Alloying C. Quenching
B. Tempering D. Refining
Alloying
What are interstitial alloying elements?
A. Atoms that substitute parent metal atoms in the atomic matrix
B. Atoms smaller than the parent metal atoms that fit into spaces in the lattice
C. Atoms that improve ductility in the metal
D. Atoms larger than the parent metal atoms that replace the lattice structure
Atoms smaller than the parent metal atoms that fit into spaces in the lattice
What is the effect of adding alloying elements to a pure metal’s atomic matrix?
A. It reduces the strength and increases ductility.
B. It creates a smoother surface for better conductivity.
C. It increases the strength by straining the atomic lattice.
D. It lowers the melting point of the material.
It increases the strength by straining the atomic lattice
Which of the following is an example of substitutional alloying?
A. Carbon added to iron, creating steel
B. Zinc replacing copper atoms, creating brass
C. Oxygen atoms forming oxides with metals
D. Hydrogen atoms fitting into a metal lattice
Zinc replacing copper atoms, creating brass
What is one reason elements are added to metals during alloying?
A. To reduce the strength of the metal
B. To improve corrosion or oxidation resistance
C. To remove impurities from the material
D. To decrease the cost of production
To improve corrosion or oxidation resistance
What are the primary elements always present in carbon steels?
A. Carbon, manganese, phosphorous, sulfur, and silicon
B. Hydrogen, oxygen, nitrogen, and chromium
C. Nickel, copper, molybdenum, and tin
D. Carbon, chromium, silicon, and nickel
Carbon, manganese, phosphorous, sulfur, and silicon
What is the effect of adding significant amounts of carbon to steel?
A. Increased weldability and formability
B. Increased strength and hardness but reduced formability and weldability
C. Improved corrosion resistance and oxidation stability
D. Reduced manufacturing cost and increased machineability
Increased strength and hardness but reduced formability and weldability
What is the purpose of adhering to material specification limits in piping design?
A. To reduce the cost of raw materials
B. To ensure reliability, predictability, and repeatability of material behavior
C. To simplify the alloying process for manufacturers
D. To increase the flexibility of design specifications
To ensure reliability, predictability, and repeatability of material behavior
What is a ‘ladle analysis’ in the context of material testing?
A. A test of the metal’s behavior under heat treatment
B. A chemical analysis performed on a sample of molten metal
C. A test of the final product’s weldability and formability
D. A method of checking corrosion resistance in a finished product
A chemical analysis performed on a sample of molten metal
How are mechanical properties of metals defined?
A. By the chemical composition of the metal
B. By the material’s response to applied force
C. By the thermal behavior of the material
D. By the electrical conductivity of the metal
By the material’s response to applied force