FREE AWS CWI Questions and Answers
When the welder moves too slowly, surplus weld metal flows out of the joint and lays on the base metal surface without fusing, resulting in what kind of weld discontinuity?
The correct answer is "Underfill."
Which of the following discontinuities has a lower visual probability of being detected?
The correct answer is "Lamellar tear." Here's an explanation for why it has a lower visual probability of being detected compared to the other discontinuities listed:
Lamellar tearing is a discontinuity that occurs within the base metal, usually beneath the weld joint, due to the presence of internal stresses. Unlike surface defects like undercut, toe cracks, and overlap, lamellar tears are internal discontinuities and may not be readily visible without more advanced inspection techniques such as ultrasonic testing or radiography. This makes them less likely to be detected visually during a standard visual inspection.
Key points to remember are:
The key points to remember in the provided options pertain to quality control and inspection processes within fabrication.
Points where an inspection and acceptance are required prior to accomplishment for any further fabrication: This point highlights the critical stage in the fabrication process where an inspection and acceptance must occur before proceeding with any additional fabrication steps. Essentially, it emphasizes the importance of quality control measures at specific junctures to ensure that the work meets predetermined standards before advancing further.
Prioritizing inspection and acceptance before further fabrication is essential for maintaining quality, preventing defects, and optimizing efficiency in fabrication processes.
One should measure the preheat temperature.
"The thickness of the joint but no less than 3 in from the joint along the entire length of the joint."
Measuring the preheat temperature at a distance of no less than 3 inches from the joint along the entire length of the joint ensures accurate, consistent heating and helps maintain the quality and integrity of the welded joint.
Reviewing the drawings and specifications is recommended:
The correct answer is "All of the above." Reviewing the drawings and specifications is recommended at various stages of the welding process for several reasons:
Prior to Welding: Reviewing the drawings and specifications before welding is essential to ensure that the welder understands the requirements and parameters specified for the job. This helps prevent mistakes or deviations from the intended weld quality and ensures that the welding process aligns with the project's
During Welding: Continuously referring to the drawings and specifications during welding helps the welder verify that they are following the correct procedures and producing welds that meet the specified standards. It allows for real-time adjustments if any discrepancies or issues arise during the welding process.
After Welding: Reviewing the drawings and specifications after welding is completed serves as a final check to confirm that the welds meet the required dimensions, quality standards, and other specified criteria. This step helps identify any deviations or defects that may have occurred during the welding process and allows for corrective actions to be taken if necessary.
By recommending the review of drawings and specifications at all stages of the welding process, it ensures consistency, accuracy, and adherence to project requirements throughout the welding project lifecycle.
Which of the following procedures is most unlikely to result in the presence of slag in a fully fused joint?
The correct answer is not "PAW." The procedure most unlikely to result in the presence of slag in a fully fused joint is "SAW" (Submerged Arc Welding).
Of these welding techniques, which one can lead to underbead cracks?
The correct answer is "All of the above.
Welding on Contaminated Steels: Contaminated steels, such as those with high sulfur or phosphorus content, are more susceptible to underbead cracking during welding. Contaminants in the base metal can lead to the formation of brittle phases in the heat-affected zone (HAZ) adjacent to the weld, increasing the likelihood of underbead
Use of Wet Electrodes: Wet electrodes can introduce moisture into the welding process, which can lead to hydrogen embrittlement. Hydrogen absorbed by the weld metal and HAZ during welding can increase the susceptibility of the material to underbead cracking, particularly in high-strength steels.
Welding Over Paint: Welding over paint or other surface contaminants can introduce impurities into the weld, leading to the formation of brittle phases in the HAZ. Additionally, the presence of paint can create a barrier that traps moisture, increasing the risk of hydrogen embrittlement and underbead cracking.
In summary, all of these welding techniques can contribute to underbead cracking by introducing contaminants, moisture, or other factors that increase the susceptibility of the base metal and weld to cracking. Therefore, it's important to carefully consider and mitigate these factors to minimize the risk of underbead cracking during welding.
Which discontinuity is thought to be the best served?
The correct answer is "crack." Here's an explanation for why cracks are often considered the best-served discontinuity:
Cracks in welded materials are considered serious defects as they can compromise the structural integrity of the joint or component. However, cracks are usually more easily detectable compared to other discontinuities. Their distinct appearance and potential impact on structural integrity make them a focal point for inspection and repair. Cracks are typically considered the best-served discontinuity because they are more easily detectable and their presence necessitates immediate attention to ensure the structural integrity of the welded component.
The discontinuity that arises from the gas being trapped inside the weld cross-section is known as
The correct answer is indeed "Porosity."
When the welding arc is improperly terminated, the resulting weld discontinuity is known as
The correct answer is not "Crater crack." The resulting weld discontinuity when the welding arc is improperly terminated is known as "Crater crack."
• Overlap: Overlap occurs when the weld metal protrudes beyond the weld toe or when adjacent weld beads are not properly fused together.
• Undercut: Undercutting happens when the base metal next to the weld bead is not properly filled by weld metal, creating a groove or recess in the base metal along the toe of the weld.
• Incomplete fusion: Incomplete fusion occurs when the weld metal fails to properly fuse with the base metal or previous weld passes, resulting in a lack of fusion between the weld and the base metal.
• Crater crack: A crater crack forms at the end of a weld when the welding arc is abruptly terminated, causing a depression or crater in the weld metal. As the weld metal solidifies, it may contract, leading to the formation of a crack at the crater.
Therefore, the correct answer is "Crater crack," as it specifically refers to the discontinuity resulting from an improperly terminated welding arc.
What discontinuities are visible when inspected visually?
The discontinuity visible when inspected visually among the options provided is "cracks."
Cracks are visible breaks or fractures in a material. They can occur due to various reasons such as stress, fatigue, impact, or improper manufacturing processes. When inspecting a material or a structure visually, cracks are often readily apparent, especially if they are large or located on the surface. Cracks are typically the most easily identifiable type of discontinuity when inspected visually due to their distinct appearance and the potential for significant impact on the integrity of a material or structure.