CWI Code Book Application 5 — Questions and Answers
Question 1: Under AWS D1.1, what is the maximum length of a single acceptable rounded indication in a groove weld inspected by RT, for a weld in base metal 3/4 inch thick?
- 3/16 inch (4.8 mm) (Correct answer)
- 1/4 inch (6.4 mm)
- 3/8 inch (9.5 mm)
- 1/2 inch (12.7 mm)
Correct answer: 3/16 inch (4.8 mm)
AWS D1.1 limits individual rounded indications in RT to a maximum of t/4 for metal up to 1 inch thick, so for 3/4 inch base metal the limit is 3/16 inch.
Question 2: Per AWS D1.1, when must weld tabs (run-off tabs) be removed after welding?
- Always, after the weld is complete
- Only when specified by the engineer of record (Correct answer)
- Only on statically loaded structures
- Only when the weld will be inspected by UT
Correct answer: Only when specified by the engineer of record
AWS D1.1 requires removal of weld tabs only when specified by the engineer; if not specified, the contractor may leave them in place.
Question 3: In ASME Section IX, what is the purpose of the P-number system for base metals?
- To rank metals by tensile strength for design purposes
- To group metals with similar welding characteristics to reduce the number of qualifications required (Correct answer)
- To classify metals by their carbon equivalent for preheat calculation
- To identify metals approved for high-pressure service
Correct answer: To group metals with similar welding characteristics to reduce the number of qualifications required
ASME P-numbers group base metals with similar welding characteristics so that qualifying a WPS on one metal in the group qualifies it for all metals in that group.
Question 4: According to AWS D1.1, what condition exists when weld discontinuities are evaluated using the 'limitations on accumulation' rule in RT inspection?
- Individual indications within limits but aggregate length exceeds permitted level
- No single indication exceeds the size limit but more than five exist
- Indications clustered within a 12-inch weld length exceed 2 inches total (Correct answer)
- Any indication within one weld diameter of another indication
Correct answer: Indications clustered within a 12-inch weld length exceed 2 inches total
AWS D1.1 applies an accumulation rule that rejects when the total length of acceptable indications in any 12-inch weld length exceeds 2 inches, preventing clustered marginal defects.
Question 5: Under AWS D1.1, a complete joint penetration groove weld made from one side without backing requires which testing to confirm full fusion at the root?
- Visual inspection only
- PT or MT to confirm surface condition
- RT or UT to verify root fusion (Correct answer)
- Hardness testing of the weld zone
Correct answer: RT or UT to verify root fusion
CJP welds made from one side without backing require RT or UT to verify complete root fusion since visual inspection cannot reveal subsurface root defects.
Question 6: Per AWS D1.1, what is the maximum groove angle permitted for a single-V groove weld in a prequalified joint design (flat position)?
- No maximum; only minimum angle is specified (Correct answer)
- 60 degrees
- 75 degrees
- 90 degrees
Correct answer: No maximum; only minimum angle is specified
AWS D1.1 prequalified joint designs specify minimum groove angles to ensure access for welding but do not impose a maximum angle limit.
Question 7: When AWS D1.1 requires a 'CVN test' as a supplemental essential variable, what property does this test measure?
- Weld metal hardness at elevated temperature
- Notch toughness (impact energy absorbed at a specified temperature) (Correct answer)
- Ultimate tensile strength of the deposited weld metal
- Ductility as measured by percent elongation
Correct answer: Notch toughness (impact energy absorbed at a specified temperature)
The Charpy V-Notch (CVN) test measures the notch toughness of weld metal by determining the energy absorbed when a notched specimen is fractured at a specified temperature.
CWI Code Book Application 5
Under AWS D1.1, what is the maximum length of a single acceptable rounded indication in a groove weld inspected by RT, for a weld in base metal 3/4 inch thick?