WCL Inspection & Quality Control 2 — Questions and Answers
Question 1: Which non-destructive testing method uses high-frequency sound waves to detect internal weld defects?
- Magnetic particle testing
- Ultrasonic testing (Correct answer)
- Liquid penetrant testing
- Visual inspection
Correct answer: Ultrasonic testing
Ultrasonic testing (UT) transmits high-frequency sound waves through the weld to detect internal discontinuities by analyzing reflected signals.
Question 2: What is the primary purpose of a weld procedure specification (WPS)?
- To document the welder's qualifications
- To provide direction for making production welds (Correct answer)
- To record tensile strength test results
- To list approved filler metals only
Correct answer: To provide direction for making production welds
A WPS provides written instructions that direct welders in making production welds to the required quality and to meet the applicable code.
Question 3: A porosity defect in a weld is caused by:
- Excessive heat input
- Gas trapped during solidification (Correct answer)
- Improper joint fit-up
- Incorrect electrode angle
Correct answer: Gas trapped during solidification
Porosity occurs when gas becomes entrapped within the weld metal as it solidifies, forming voids or pores.
Question 4: According to AWS D1.1, incomplete fusion is classified as a:
- Acceptable geometric discontinuity
- Rejectable weld discontinuity (Correct answer)
- Minor surface irregularity
- Acceptable porosity type
Correct answer: Rejectable weld discontinuity
Incomplete fusion is a rejectable discontinuity under AWS D1.1 because it represents a lack of bond between the weld metal and the base metal or between weld passes.
Question 5: When performing radiographic testing, what does a darker area on the film typically indicate?
- A denser area with no defects
- An area of greater radiation absorption
- A void or less dense area such as porosity (Correct answer)
- The heat-affected zone boundary
Correct answer: A void or less dense area such as porosity
Darker areas on radiographic film indicate regions where more radiation passed through, which typically corresponds to voids, cracks, or porosity with lower density than sound metal.
Question 6: What is undercut in a weld?
- A groove melted into base metal adjacent to the weld toe (Correct answer)
- Weld metal that extends beyond the joint
- Incomplete penetration at the root
- A crack parallel to the weld axis
Correct answer: A groove melted into base metal adjacent to the weld toe
Undercut is a groove or channel melted into the base metal at the toe of the weld that reduces the effective cross-section and acts as a stress concentrator.
Question 7: Which document records the actual variables used during a weld procedure qualification test?
- Welder Qualification Record (WQR)
- Procedure Qualification Record (PQR) (Correct answer)
- Weld Procedure Specification (WPS)
- Material Test Report (MTR)
Correct answer: Procedure Qualification Record (PQR)
The Procedure Qualification Record (PQR) documents the actual welding variables used and the test results obtained during procedure qualification testing.
WCL Inspection & Quality Control 2
Which non-destructive testing method uses high-frequency sound waves to detect internal weld defects?