WCL Inspection & Quality Control 5 — Questions and Answers
Question 1: A weld map is used in quality control to:
- Show the amperage settings for each weld pass
- Identify and locate all welds in a fabrication for traceability (Correct answer)
- Record the cooling rate after each weld
- List the qualifications of each welder
Correct answer: Identify and locate all welds in a fabrication for traceability
A weld map identifies the location and designation of all welds in a fabrication, enabling traceability between welds and the inspectors, procedures, and welders associated with them.
Question 2: What is the primary purpose of performing a bend test on a weld?
- To measure hardness of the weld metal
- To evaluate ductility and soundness of the weld (Correct answer)
- To determine tensile strength only
- To check for surface porosity
Correct answer: To evaluate ductility and soundness of the weld
Bend tests evaluate the ductility of the weld and heat-affected zone and reveal internal discontinuities such as lack of fusion or porosity that open under bending stress.
Question 3: According to AWS D1.1, which of the following requires a visual inspection before welding begins?
- Joint fit-up, cleanliness, and alignment (Correct answer)
- Post-weld heat treatment temperature only
- NDT certification of the inspector
- Tensile properties of the filler metal
Correct answer: Joint fit-up, cleanliness, and alignment
Pre-weld visual inspection verifies that joint fit-up, alignment, root opening, cleanliness, and other variables meet the requirements of the WPS before welding starts.
Question 4: Slag inclusions in a weld are most commonly caused by:
- Excessive preheat temperature
- Improper interpass cleaning between weld passes (Correct answer)
- Using low-hydrogen electrodes
- High travel speed on the final pass
Correct answer: Improper interpass cleaning between weld passes
Slag inclusions result from failure to completely remove slag between weld passes, allowing solidified flux or slag to be trapped by subsequent passes.
Question 5: What is the significance of the 'essential variable' concept in AWS D1.1 procedure qualification?
- Essential variables may be changed without requalification
- Changing an essential variable requires requalification of the WPS (Correct answer)
- Essential variables apply only to welder qualifications
- Essential variables are listed in the material test report
Correct answer: Changing an essential variable requires requalification of the WPS
Essential variables are welding parameters that, when changed beyond prescribed limits, require requalification of the WPS because they can significantly affect weld mechanical properties.
Question 6: When performing visual inspection after welding, what is the minimum interpass temperature requirement intended to control?
- The cooling rate to prevent distortion only
- Heat buildup that could degrade toughness or cause cracking (Correct answer)
- Slag viscosity during welding
- Electrode moisture content
Correct answer: Heat buildup that could degrade toughness or cause cracking
Maximum interpass temperature limits prevent excessive heat buildup between passes that can degrade the toughness of the weld and heat-affected zone, particularly in low-alloy and high-strength steels.
Question 7: A CWI notices that the weld reinforcement (crown) on a groove weld is excessively high. This condition is:
- Acceptable because more weld metal means stronger joints
- Rejectable if it exceeds code-specified limits (Correct answer)
- Not addressed by AWS D1.1
- Only a concern for pipe welding codes
Correct answer: Rejectable if it exceeds code-specified limits
Excessive weld reinforcement is rejectable when it exceeds the limits specified in the applicable code, as it can create stress concentrations and indicates lack of control over the welding process.
WCL Inspection & Quality Control 5
A weld map is used in quality control to: