CWI Fundamentals 4 — Questions and Answers
Question 1: A Welding Procedure Specification (WPS) must be supported by:
- A Procedure Qualification Record (PQR) (Correct answer)
- A Welder Performance Qualification (WPQ)
- A certified inspection report
- An approved engineering drawing
Correct answer: A Procedure Qualification Record (PQR)
The PQR documents the actual test results from welding a test coupon to confirm the WPS parameters produce welds with acceptable mechanical properties.
Question 2: Which type of weld joint is formed when two members lie in the same plane and their edges are joined?
- T-joint
- Corner joint
- Butt joint (Correct answer)
- Lap joint
Correct answer: Butt joint
A butt joint connects two members that lie approximately in the same plane with their edges joined along the seam.
Question 3: When hydrogen-induced cracking (HIC) is a concern, which electrode storage practice is most important?
- Storing electrodes in a freezer to prevent oxidation
- Keeping low-hydrogen electrodes in a heated oven before use (Correct answer)
- Removing electrodes from packaging only after the weld area is preheated
- Soaking electrodes in oil to maintain moisture balance
Correct answer: Keeping low-hydrogen electrodes in a heated oven before use
Low-hydrogen electrodes must be stored in a holding oven at the manufacturer-specified temperature (typically 250–300°F) to prevent moisture absorption that leads to HIC.
Question 4: What does the 'F number' classification of a filler metal indicate in ASME and AWS qualification codes?
- Minimum tensile strength of the deposited weld metal
- The flux type used in the electrode coating
- A grouping of filler metals with similar usability characteristics for welder qualification (Correct answer)
- The maximum interpass temperature for the filler metal
Correct answer: A grouping of filler metals with similar usability characteristics for welder qualification
F numbers group filler metals by usability characteristics so that a welder qualified with one filler metal in the group is qualified for others in the same group.
Question 5: An inspector measures a fillet weld and finds its actual throat is larger than specified. This condition is known as:
- Insufficient throat
- Excessive convexity (Correct answer)
- Overlap
- Burn-through
Correct answer: Excessive convexity
Excessive convexity means the weld face profile projects too far outward, resulting in a larger-than-required actual throat and wasted weld metal.
Question 6: Which of the following best describes 'interpass temperature' in a multi-pass weld?
- The temperature of the base metal before welding begins
- The temperature of the weld metal at the start of each successive pass (Correct answer)
- The cooling temperature at which the weld is stress relieved
- The ambient temperature of the welding environment
Correct answer: The temperature of the weld metal at the start of each successive pass
Interpass temperature is the temperature of the previously deposited weld bead (and adjacent base metal) just before the next pass is started.
Question 7: In ultrasonic testing (UT) of welds, what does a 'transducer' do?
- Measures the electrical conductivity of the weld metal
- Converts electrical energy into ultrasonic sound waves and vice versa (Correct answer)
- Applies magnetic flux to detect surface cracks
- Emits X-radiation that exposes a film image
Correct answer: Converts electrical energy into ultrasonic sound waves and vice versa
A transducer (probe) converts electrical pulses into high-frequency sound waves directed into the material and converts returning echoes back into electrical signals for display.
CWI Fundamentals 4
A Welding Procedure Specification (WPS) must be supported by: