CWB Welding Inspector Level 3 Exam
ACTUAL EXAM 2026/2027 | Verified Q&A |
Pass Guaranteed - A+ Graded
Section 1: Welding Processes & Procedures (15 Questions)
Q1: A welder is using the spray transfer mode in GMAW (MIG) welding on carbon steel. Which of the
following shielding gas mixtures is most commonly associated with this transfer mode?
A. 100% Carbon Dioxide (CO₂)
B. 75% Argon / 25% Carbon Dioxide
C. 90% Argon / 10% Carbon Dioxide [CORRECT]
D. 100% Argon
Rationale: Spray transfer requires at least 80-85% argon to achieve the fine droplet spray pattern, with
90% argon / 10% CO₂ being the standard mixture for carbon steel. Pure CO₂ (100%) produces globular
transfer, not spray. Pure argon lacks the oxide-cleaning action needed for steel spray transfer.
Q2: When calculating heat input for a welding procedure, which formula is correct according to CSA
W59?
A. Voltage × Current × Travel Speed
B. (Voltage × Current × 60) / Travel Speed [CORRECT]
C. (Voltage × Current) / (Travel Speed × 60)
D. Voltage × Current / Travel Speed
Rationale: The correct formula is (Voltage × Current × 60) / Travel Speed, where travel speed is in
mm/min, giving heat input in J/mm. The factor of 60 converts minutes to seconds. Omitting this factor
or inverting the relationship gives incorrect values that could lead to non-compliant welding procedures.
Q3: A welder is performing SMAW (stick welding) on a 25 mm thick steel plate with a low-hydrogen
electrode. What is the minimum preheat temperature required if the carbon equivalent (CE) is 0.42%
and the ambient temperature is 5°C?
,A. No preheat required
B. 10°C
C. 75°C [CORRECT]
D. 150°C
Rationale: According to CSA W59 Table 5.2, for thickness 25 mm and CE 0.42%, minimum preheat is
75°C when ambient is below 10°C. No preheat applies to thinner sections or lower CE. Higher preheat
temperatures are for thicker sections, higher CE, or lower ambient temperatures.
Q4: In FCAW (Flux-Cored Arc Welding), what is the primary purpose of the flux contained within the
electrode core?
A. To increase travel speed only
B. To provide shielding gas, deoxidizers, and slag-forming compounds [CORRECT]
C. To conduct electricity only
D. To cool the weld puddle
Rationale: The flux in FCAW electrodes serves multiple functions: generating shielding gases to protect
the molten weld, providing deoxidizers to clean the weld metal, and forming slag to protect and shape
the solidifying weld. Self-shielded FCAW relies entirely on flux-generated gases, while gas-shielded
FCAW supplements external shielding gas.
Q5: A welding procedure specifies GTAW (TIG) welding of aluminum using AC current. What is the
primary advantage of AC over DCEN for this application?
A. Higher deposition rates
B. Cleaning action to remove aluminum oxide [CORRECT]
C. Deeper penetration
D. Reduced tungsten erosion
Rationale: AC current provides cathodic cleaning during the electrode positive half-cycle, breaking up
the tenacious aluminum oxide layer that forms instantly on aluminum. DCEN provides deeper
penetration but no cleaning action. ACHF (high frequency) stabilizes the arc but the cleaning action
comes from the alternating polarity.
Q6: In SAW (Submerged Arc Welding), what is the function of the granular flux?
A. To increase welding speed only
B. To shield the arc, stabilize the molten metal, and control weld chemistry [CORRECT]
,C. To conduct current to the workpiece
D. To preheat the base metal
Rationale: SAW flux completely covers the arc and molten pool, preventing atmospheric contamination,
stabilizing the arc, and through alloying elements in the flux, controlling weld metal chemistry. The flux
also forms slag that shapes and protects the solidifying weld. It does not conduct current or preheat the
base metal.
Q7: A welder notices that the GMAW arc is unstable with excessive spatter when using 100% CO₂
shielding gas. Which parameter change would most likely improve stability?
A. Increase voltage and use inductance control [CORRECT]
B. Decrease wire feed speed
C. Switch to DCEN polarity
D. Reduce stick-out length only
Rationale: Increasing voltage and using inductance control stabilizes the globular transfer that occurs
with pure CO₂, reducing spatter. Pure CO₂ cannot achieve true spray transfer regardless of parameters.
DCEN is never used for GMAW on steel. Stick-out affects current density but cannot overcome the
fundamental transfer mode limitations of CO₂.
Q8: When qualifying a welding procedure for GMAW-S (short-circuiting transfer), which essential
variable would require requalification if changed beyond specified limits?
A. Changing from 90% Ar/10% CO₂ to 98% Ar/2% O₂
B. Increasing electrode diameter from 0.9 mm to 1.2 mm [CORRECT]
C. Changing from one brand of ER70S-6 to another brand of ER70S-6
D. Increasing preheat from 10°C to 20°C
Rationale: Electrode diameter is an essential variable for GMAW procedure qualification because it
affects current density, deposition rate, and heat input. Shielding gas composition within the same
classification (Type 1 to Type 1) does not require requalification. Brand changes within the same
classification are acceptable. Minor preheat increases within code limits are permitted.
Q9: A welder is experiencing tungsten inclusions when performing GTAW on stainless steel. What is the
most likely cause?
A. Using too low amperage
B. Contact between tungsten and molten puddle or filler metal [CORRECT]
, C. Using DCEN instead of DCEP
D. Excessive shielding gas flow
Rationale: Tungsten inclusions occur when the electrode touches the molten weld pool or filler metal,
contaminating the weld with tungsten particles. This is typically caused by improper torch angle,
excessive electrode extension, or welder error. Low amperage causes poor penetration but not tungsten
inclusion. DCEN is correct for steel. Excessive gas flow causes turbulence, not inclusions.
Q10: In SMAW, what is the purpose of the coating on a low-hydrogen E7018 electrode?
A. To increase deposition rate only
B. To provide shielding gas, slag, and low-hydrogen weld metal [CORRECT]
C. To conduct electricity
D. To cool the electrode
Rationale: The coating on E7018 electrodes generates CO₂ shielding gas, forms protective slag, and most
importantly, provides low-hydrogen weld metal to prevent hydrogen-induced cracking in susceptible
steels. The coating also contains deoxidizers and alloying elements. Proper storage (ovens) is essential to
maintain low-hydrogen characteristics.
Q11: A welding procedure for critical structural application requires impact testing at -40°C. Which
welding process and filler metal combination is most likely to meet toughness requirements?
A. FCAW-S with E71T-1 electrode
B. SAW with neutral flux and low-carbon wire
C. SMAW with E7018-1 electrode [CORRECT]
D. GMAW with ER70S-6 wire and 100% CO₂
Rationale: SMAW with E7018-1 (low-temperature impact rated) electrode is specifically designed for
toughness at low temperatures, with diffusible hydrogen control and fine-grained weld metal. E7018-1
has mandatory impact testing requirements. FCAW-S and GMAW with CO₂ typically produce lower
toughness. SAW can achieve good toughness but requires careful flux-wire combination selection.
Q12: When performing root pass welding on a pipe joint using GTAW, what technique is used to prevent
suck-back (internal concavity)?
A. Increase amperage significantly
B. Use backing gas and control root opening/penetration [CORRECT]
C. Use larger diameter filler wire
D. Increase travel speed
ACTUAL EXAM 2026/2027 | Verified Q&A |
Pass Guaranteed - A+ Graded
Section 1: Welding Processes & Procedures (15 Questions)
Q1: A welder is using the spray transfer mode in GMAW (MIG) welding on carbon steel. Which of the
following shielding gas mixtures is most commonly associated with this transfer mode?
A. 100% Carbon Dioxide (CO₂)
B. 75% Argon / 25% Carbon Dioxide
C. 90% Argon / 10% Carbon Dioxide [CORRECT]
D. 100% Argon
Rationale: Spray transfer requires at least 80-85% argon to achieve the fine droplet spray pattern, with
90% argon / 10% CO₂ being the standard mixture for carbon steel. Pure CO₂ (100%) produces globular
transfer, not spray. Pure argon lacks the oxide-cleaning action needed for steel spray transfer.
Q2: When calculating heat input for a welding procedure, which formula is correct according to CSA
W59?
A. Voltage × Current × Travel Speed
B. (Voltage × Current × 60) / Travel Speed [CORRECT]
C. (Voltage × Current) / (Travel Speed × 60)
D. Voltage × Current / Travel Speed
Rationale: The correct formula is (Voltage × Current × 60) / Travel Speed, where travel speed is in
mm/min, giving heat input in J/mm. The factor of 60 converts minutes to seconds. Omitting this factor
or inverting the relationship gives incorrect values that could lead to non-compliant welding procedures.
Q3: A welder is performing SMAW (stick welding) on a 25 mm thick steel plate with a low-hydrogen
electrode. What is the minimum preheat temperature required if the carbon equivalent (CE) is 0.42%
and the ambient temperature is 5°C?
,A. No preheat required
B. 10°C
C. 75°C [CORRECT]
D. 150°C
Rationale: According to CSA W59 Table 5.2, for thickness 25 mm and CE 0.42%, minimum preheat is
75°C when ambient is below 10°C. No preheat applies to thinner sections or lower CE. Higher preheat
temperatures are for thicker sections, higher CE, or lower ambient temperatures.
Q4: In FCAW (Flux-Cored Arc Welding), what is the primary purpose of the flux contained within the
electrode core?
A. To increase travel speed only
B. To provide shielding gas, deoxidizers, and slag-forming compounds [CORRECT]
C. To conduct electricity only
D. To cool the weld puddle
Rationale: The flux in FCAW electrodes serves multiple functions: generating shielding gases to protect
the molten weld, providing deoxidizers to clean the weld metal, and forming slag to protect and shape
the solidifying weld. Self-shielded FCAW relies entirely on flux-generated gases, while gas-shielded
FCAW supplements external shielding gas.
Q5: A welding procedure specifies GTAW (TIG) welding of aluminum using AC current. What is the
primary advantage of AC over DCEN for this application?
A. Higher deposition rates
B. Cleaning action to remove aluminum oxide [CORRECT]
C. Deeper penetration
D. Reduced tungsten erosion
Rationale: AC current provides cathodic cleaning during the electrode positive half-cycle, breaking up
the tenacious aluminum oxide layer that forms instantly on aluminum. DCEN provides deeper
penetration but no cleaning action. ACHF (high frequency) stabilizes the arc but the cleaning action
comes from the alternating polarity.
Q6: In SAW (Submerged Arc Welding), what is the function of the granular flux?
A. To increase welding speed only
B. To shield the arc, stabilize the molten metal, and control weld chemistry [CORRECT]
,C. To conduct current to the workpiece
D. To preheat the base metal
Rationale: SAW flux completely covers the arc and molten pool, preventing atmospheric contamination,
stabilizing the arc, and through alloying elements in the flux, controlling weld metal chemistry. The flux
also forms slag that shapes and protects the solidifying weld. It does not conduct current or preheat the
base metal.
Q7: A welder notices that the GMAW arc is unstable with excessive spatter when using 100% CO₂
shielding gas. Which parameter change would most likely improve stability?
A. Increase voltage and use inductance control [CORRECT]
B. Decrease wire feed speed
C. Switch to DCEN polarity
D. Reduce stick-out length only
Rationale: Increasing voltage and using inductance control stabilizes the globular transfer that occurs
with pure CO₂, reducing spatter. Pure CO₂ cannot achieve true spray transfer regardless of parameters.
DCEN is never used for GMAW on steel. Stick-out affects current density but cannot overcome the
fundamental transfer mode limitations of CO₂.
Q8: When qualifying a welding procedure for GMAW-S (short-circuiting transfer), which essential
variable would require requalification if changed beyond specified limits?
A. Changing from 90% Ar/10% CO₂ to 98% Ar/2% O₂
B. Increasing electrode diameter from 0.9 mm to 1.2 mm [CORRECT]
C. Changing from one brand of ER70S-6 to another brand of ER70S-6
D. Increasing preheat from 10°C to 20°C
Rationale: Electrode diameter is an essential variable for GMAW procedure qualification because it
affects current density, deposition rate, and heat input. Shielding gas composition within the same
classification (Type 1 to Type 1) does not require requalification. Brand changes within the same
classification are acceptable. Minor preheat increases within code limits are permitted.
Q9: A welder is experiencing tungsten inclusions when performing GTAW on stainless steel. What is the
most likely cause?
A. Using too low amperage
B. Contact between tungsten and molten puddle or filler metal [CORRECT]
, C. Using DCEN instead of DCEP
D. Excessive shielding gas flow
Rationale: Tungsten inclusions occur when the electrode touches the molten weld pool or filler metal,
contaminating the weld with tungsten particles. This is typically caused by improper torch angle,
excessive electrode extension, or welder error. Low amperage causes poor penetration but not tungsten
inclusion. DCEN is correct for steel. Excessive gas flow causes turbulence, not inclusions.
Q10: In SMAW, what is the purpose of the coating on a low-hydrogen E7018 electrode?
A. To increase deposition rate only
B. To provide shielding gas, slag, and low-hydrogen weld metal [CORRECT]
C. To conduct electricity
D. To cool the electrode
Rationale: The coating on E7018 electrodes generates CO₂ shielding gas, forms protective slag, and most
importantly, provides low-hydrogen weld metal to prevent hydrogen-induced cracking in susceptible
steels. The coating also contains deoxidizers and alloying elements. Proper storage (ovens) is essential to
maintain low-hydrogen characteristics.
Q11: A welding procedure for critical structural application requires impact testing at -40°C. Which
welding process and filler metal combination is most likely to meet toughness requirements?
A. FCAW-S with E71T-1 electrode
B. SAW with neutral flux and low-carbon wire
C. SMAW with E7018-1 electrode [CORRECT]
D. GMAW with ER70S-6 wire and 100% CO₂
Rationale: SMAW with E7018-1 (low-temperature impact rated) electrode is specifically designed for
toughness at low temperatures, with diffusible hydrogen control and fine-grained weld metal. E7018-1
has mandatory impact testing requirements. FCAW-S and GMAW with CO₂ typically produce lower
toughness. SAW can achieve good toughness but requires careful flux-wire combination selection.
Q12: When performing root pass welding on a pipe joint using GTAW, what technique is used to prevent
suck-back (internal concavity)?
A. Increase amperage significantly
B. Use backing gas and control root opening/penetration [CORRECT]
C. Use larger diameter filler wire
D. Increase travel speed
