CWI WPS and PQR Qualification 5 — Questions and Answers
Question 1: A WPS specifies a minimum preheat temperature of 300°F. During production welding the inspector measures the base metal temperature at 275°F. What action should the inspector take?
- Allow welding to proceed since the difference is within 10% tolerance
- Stop welding and require the base metal to be reheated to at least 300°F before resuming (Correct answer)
- Notify the engineer and continue welding while monitoring closely
- Accept the weld if final NDE passes
Correct answer: Stop welding and require the base metal to be reheated to at least 300°F before resuming
Preheat is an essential variable; welding below the WPS minimum preheat temperature is a nonconformance that must be corrected before welding continues.
Question 2: Under ASME Section IX, postweld heat treatment (PWHT) conditions (temperature range and holding time) are classified as:
- Nonessential variables for all processes
- Essential variables only for P-5, P-6, and P-7 base metals
- Essential variables for all base metals (Correct answer)
- Supplementary essential variables when impact testing is required
Correct answer: Essential variables for all base metals
PWHT temperature range and time are essential variables under ASME Section IX QW-407; any change in PWHT conditions requires requalification.
Question 3: During SAW procedure qualification, the inspector notes the flux used is a different lot number than specified in the WPS. Under ASME Section IX, is this a problem?
- No, flux lot number is not a controlled variable under ASME Section IX (Correct answer)
- Yes, any flux change requires a new PQR regardless of classification
- Yes, if the flux brand name changes
- No, provided the flux basicity index is within 5% of the original
Correct answer: No, flux lot number is not a controlled variable under ASME Section IX
ASME Section IX does not identify flux lot number as an essential, supplementary essential, or nonessential variable; the classification and type are what matter.
Question 4: For a FCAW-G (gas-shielded flux-cored arc welding) WPS, adding shielding gas backing where none was previously used is considered what type of variable under ASME Section IX?
- Nonessential variable
- Essential variable (Correct answer)
- Administrative variable
- It has no variable designation
Correct answer: Essential variable
Adding or deleting backing gas (shielding gas on the back side) is an essential variable for FCAW-G under ASME Section IX QW-408.
Question 5: A CWI reviewing a WPS notices it does not address interpass temperature. What is the correct interpretation under ASME Section IX?
- The WPS is automatically rejected if interpass temperature is omitted
- If no maximum interpass temperature is listed, the WPS is uncontrolled and invalid
- Interpass temperature is a nonessential variable and its omission does not invalidate the WPS (Correct answer)
- The omission implies no temperature control is needed only for P-1 materials
Correct answer: Interpass temperature is a nonessential variable and its omission does not invalidate the WPS
Under ASME Section IX, maximum interpass temperature is a nonessential variable and does not need to be listed for the WPS to be valid.
Question 6: Under AWS D1.1 Table 4.5, which welding process is permitted to use a single-pass weld for procedure qualification regardless of base metal thickness?
- SMAW
- GMAW-S (short-circuit transfer)
- ESW (electroslag welding) (Correct answer)
- FCAW
Correct answer: ESW (electroslag welding)
Electroslag and electrogas welding are inherently single-pass processes, and AWS D1.1 specifically addresses their qualification under separate provisions reflecting that nature.
Question 7: When a procedure qualification test coupon is welded in the 6G position (pipe inclined 45°), which welding positions does it qualify for groove welds under ASME Section IX?
- Flat and horizontal only
- All groove weld positions (Correct answer)
- Vertical and overhead only
- 6G position only
Correct answer: All groove weld positions
Qualification in the 6G (inclined fixed pipe) position qualifies all groove weld positions under ASME Section IX QW-461.
CWI WPS and PQR Qualification 5
A WPS specifies a minimum preheat temperature of 300°F.
During production welding the inspector measures the base metal temperature at 275°F.
What action should the inspector take?