CWI Ultimate Review 5 — Questions and Answers
Question 1: In liquid penetrant testing (PT), what is the function of the developer?
- To clean the surface before applying penetrant
- To draw trapped penetrant out of discontinuities and provide a contrasting background (Correct answer)
- To remove excess penetrant from the surface
- To harden the penetrant for easier visual inspection
Correct answer: To draw trapped penetrant out of discontinuities and provide a contrasting background
The developer draws (blots) the penetrant out of discontinuities by capillary action and provides a contrasting background to make indications visible.
Question 2: What does a 'hot crack' (solidification crack) in a weld typically look like on a radiograph?
- A rounded, dark spot
- A straight or branching line following the weld centerline (Correct answer)
- A uniform gray shadow across the weld
- A white, high-density inclusion
Correct answer: A straight or branching line following the weld centerline
Solidification (hot) cracks typically appear as straight or slightly jagged lines following the weld centerline on a radiograph, as they form during solidification in the center of the weld pool.
Question 3: Which of the following base metals is classified as P-Number 1 in ASME Section IX?
- Austenitic stainless steel (304)
- Carbon steel (A36) (Correct answer)
- Low-alloy Cr-Mo steel (P91)
- Duplex stainless steel
Correct answer: Carbon steel (A36)
ASME Section IX P-Number 1 covers carbon steels such as A36, A53, and similar materials with low carbon content and good weldability.
Question 4: A CWI measuring weld reinforcement finds it to be 5/32 in (4.0 mm) on a 3/8 in (9.5 mm) butt weld. Per AWS D1.1, this is:
- Acceptable; reinforcement has no limit
- Acceptable; 5/32 in is within the 3/16 in maximum
- Rejectable; the maximum reinforcement for this thickness is 1/8 in (Correct answer)
- Acceptable only if the transition slope meets code requirements
Correct answer: Rejectable; the maximum reinforcement for this thickness is 1/8 in
AWS D1.1 limits weld face reinforcement to 1/8 in (3.2 mm) maximum for groove welds in base metal up to and including 3/4 in thick, so 5/32 in exceeds this limit.
Question 5: Overlap (cold lap) in a weld is caused by:
- Excessive welding current
- Weld metal flowing beyond the fusion zone onto the base metal surface without fusing (Correct answer)
- Insufficient base metal thickness
- High interpass temperature
Correct answer: Weld metal flowing beyond the fusion zone onto the base metal surface without fusing
Overlap occurs when weld metal flows over the base metal surface and solidifies without achieving fusion, typically caused by too low a current, too slow a travel speed, or incorrect electrode angle.
Question 6: For a CWI performing visual inspection (VT) of a weld, what is the maximum distance from which inspection should be performed per standard practice?
- 6 inches (150 mm)
- 12 inches (305 mm)
- 24 inches (610 mm) (Correct answer)
- 36 inches (915 mm)
Correct answer: 24 inches (610 mm)
Standard VT practice requires the inspector to be within 24 inches (610 mm) of the surface being inspected, with the eye at an angle not less than 30° to the surface.
Question 7: Which of the following best describes the role of a Certified Welding Inspector (CWI) regarding welder qualifications?
- The CWI performs the qualification welds on behalf of the welder
- The CWI witnesses, documents, and verifies that qualification tests are conducted per code requirements (Correct answer)
- The CWI issues permanent welder certifications that never expire
- The CWI approves electrode selections for each individual welder
Correct answer: The CWI witnesses, documents, and verifies that qualification tests are conducted per code requirements
The CWI's role in welder qualification is to witness and document the qualification tests, verify they meet code requirements, and ensure proper records are maintained.
CWI Ultimate Review 5
In liquid penetrant testing (PT), what is the function of the developer?