CWI Exam Prep Free practice test →

Free CWI Practice Questions

10 free, exam-style Certified Welding Inspector (CWI) practice questions with answers and source citations. No signup required. Work through them below, then take the full free CWI practice test to study all study topics.

The CWI exam has 261 questions and runs 6 hours.

These 10 free CWI questions are grouped below. These are editorial study topics for organizing this practice bank. Question placements and pool sizes are not official exam assignments or weights. Reveal the answer and source citation under each question.

Study topic 1: Welding terminology, joints, welds, discontinuities, and positions

Question 1

What is the PRIMARY difference between a discontinuity and a defect?

  1. A discontinuity is always visible; a defect may not be detectable
  2. A discontinuity is always larger in size than a defect
  3. A defect exceeds the code acceptance criteria; a discontinuity may or may not
  4. A discontinuity is natural; a defect is always man-made
Show answer & source

Correct answer: C - A defect exceeds the code acceptance criteria; a discontinuity may or may not

Source: Definitions — Discontinuities | Discontinuity vs. Defect

Study topic 2: Joining and cutting processes

Question 2

A welding inspector observes a welder using E6010 electrodes for the root pass on a pipe weld. Which polarity should the welder be using?

  1. AC with high frequency stabilization
  2. DCEN (straight polarity)
  3. DCEP (reverse polarity)
  4. Either DCEN or AC polarity
Show answer & source

Correct answer: C - DCEP (reverse polarity)

Source: Joining Processes — SMAW | E6010 Polarity

Study topic 3: Welding and NDE symbols

Question 3

A V-groove weld symbol below the reference line shows '60°' inside the V, '1/8' at the root, and '3/8' to the left. This specifies:

  1. A fillet weld with 3/8 inch legs at 60°
  2. A V-groove with 60° angle, 1/8 inch root opening, and 3/8 inch size
  3. A 60° bevel with 3/8 inch reinforcement
  4. A plug weld 3/8 inch in diameter
Show answer & source

Correct answer: B - A V-groove with 60° angle, 1/8 inch root opening, and 3/8 inch size

Source: Symbols — Groove Welds | Complete V-Groove Reading

Study topic 5: Welding procedures, procedure qualification, and welder qualification

Question 5

During production, the minimum preheat specified on the WPS is 200°F. The inspector measures the plate temperature at 175°F. The inspector should:

  1. Accept it because the temperature difference is within acceptable tolerance limits
  2. Require additional preheating to reach the minimum 200°F before welding continues
  3. Document the deviation and proceed with welding under close supervision
  4. Accept it if the welding procedure allows for temperature variations
Show answer & source

Correct answer: B - Require additional preheating to reach the minimum 200°F before welding continues

Source: Welding Application — Production | Preheat Compliance

Study topic 6: Nondestructive examination

Question 6

For MT to detect a discontinuity, the discontinuity must be oriented:

  1. Parallel to the magnetic flux lines
  2. Perpendicular (or nearly so) to the magnetic flux lines
  3. At an angle between 30° and 60° to the flux lines
  4. At an oblique angle to avoid flux leakage
Show answer & source

Correct answer: B - Perpendicular (or nearly so) to the magnetic flux lines

Source: NDE Fundamentals — MT | Orientation Rule

Study topic 7: Metallurgy, weldability, and heat treatment

Question 4

An inspector examining a weld on high-strength low-alloy steel discovers cracks in the HAZ 48 hours after welding was completed. These delayed cracks are MOST likely:

  1. Stress corrosion cracks from environmental exposure
  2. Hydrogen-induced (cold) cracks
  3. Reheat cracking from post-weld heat treatment
  4. Lamellar tearing from through-thickness stresses
Show answer & source

Correct answer: B - Hydrogen-induced (cold) cracks

Source: Visual Examination — Post-Weld | Delayed Hydrogen Cracking

Question 7

The four factors that must ALL be present simultaneously for hydrogen-induced cracking (cold cracking) to occur are:

  1. Hydrogen, high temperature environment, compressive stress, and austenitic microstructure
  2. Hydrogen, susceptible microstructure (martensite), tensile stress, and low temperature
  3. Oxygen contamination, pearlitic microstructure, shear stress, and elevated temperature conditions
  4. Nitrogen presence, bainitic microstructure, residual stress, and moderate temperature range
Show answer & source

Correct answer: B - Hydrogen, susceptible microstructure (martensite), tensile stress, and low temperature

Source: Metallurgy — Hydrogen Cracking | Four Factors

Study topic 8: Welding inspection calculations and conversions

Question 8

A weld specification requires a minimum heat input of 30 kJ/in. A welder is running at 26V, 220A, and 12 in/min. Does the heat input meet the minimum?

  1. Yes - HI = 34.3 kJ/in, which exceeds 30 kJ/in
  2. Yes - HI = 28.6 kJ/in, which exceeds 30 kJ/in
  3. No - HI = 28.6 kJ/in, which is below 30 kJ/in
  4. No - HI = 22.0 kJ/in, which is below 30 kJ/in
Show answer & source

Correct answer: C - No - HI = 28.6 kJ/in, which is below 30 kJ/in

Source: Calculations — Heat Input | Minimum HI Compliance

Study topic 11: Part B practical-application scenarios (text-only study)

Question 9

An inspector is evaluating a fillet weld and finds: leg size = 5/16 inch (required 1/4 inch minimum - acceptable), convexity = 3/16 inch (BOS maximum 1/16 inch for this size - rejectable). The overall disposition is:

  1. Accept - leg size is adequate
  2. Reject - convexity exceeds BOS limit
  3. Accept - only one criterion needs to pass
  4. Request engineering evaluation
Show answer & source

Correct answer: B - Reject - convexity exceeds BOS limit

Source: Part B — Mixed | Multiple Criteria — One Fails = Reject

Study topic 12: Part C code applications

Question 10

Per AWS D1.1, a fillet weld is specified as 5/16 inch. The inspector measures the actual weld and finds the leg size is 1/4 inch (undersized by 1/16 inch) over a 3-inch length of a 30-inch total weld length. Per Table 8.1, undersizing up to 1/16 inch is permitted if it does not exceed 10% of the weld length. 10% of 30 inches = 3 inches. This weld is:

  1. Rejectable - undersized welds require engineering approval regardless of length
  2. Acceptable - the undersized portion (3 inches) equals the 10% allowance (3 inches)
  3. Rejectable - undersizing tolerance applies only to intermittent welds, not continuous welds
  4. Rejectable - visual inspection is insufficient for determining undersize acceptance criteria
Show answer & source

Correct answer: B - Acceptable - the undersized portion (3 inches) equals the 10% allowance (3 inches)

Source: Part C — D1.1 Inspection | Undersized Fillet Tolerance

More CWI study topics

These topics have no free sample in the set above:

Ready for the real thing?

Practice hundreds more CWI questions with instant scoring, weak-area drills, and full exam simulations.

Start the free practice test See pricing