AWS Certified Welding Inspector (CWI) — All Questions

In shielded metal arc welding (SMAW), what primarily protects the molten weld pool from atmospheric contamination?

• a.An external supply of inert argon gas
• b.The gaseous shield and slag produced as the flux coating on the electrode burns and melts✓
• c.A granular flux fed continuously from a hopper
• d.A vacuum chamber surrounding the arc

SMAW (stick welding) uses a consumable electrode covered with a flux coating. As the arc heats the coating, it decomposes to create a shielding gas and forms a molten slag that both cover the weld pool, protecting it from oxygen and nitrogen. This is why SMAW needs no external gas bottle. Argon/CO2 shielding gas describes GMAW/GTAW; a granular flux from a hopper describes SAW.

Which welding process uses a non-consumable tungsten electrode and typically an inert shielding gas such as argon?

• a.FCAW (flux-cored arc welding)
• b.SAW (submerged arc welding)
• c.GTAW (gas tungsten arc welding)✓
• d.SMAW (shielded metal arc welding)

GTAW, also called TIG, uses a non-consumable tungsten electrode to establish the arc while filler metal is added separately by hand. Argon or helium shields the pool. It produces high-quality, precise welds and is common on thin material and stainless/aluminum. The other processes all use consumable electrodes or wire that become part of the weld.

A welder deposits weld metal and the joint later cracks along the boundary between the base metal and the weld. This region is best described as the:

• a.Heat-affected zone (HAZ)✓
• b.Root face
• c.Weld reinforcement
• d.Toe of the weld

The heat-affected zone is the base metal adjacent to the weld that did not melt but whose microstructure and properties were altered by the heat of welding. It is often the most metallurgically vulnerable region because rapid heating and cooling can harden it or reduce toughness. The root face is a joint-preparation dimension, reinforcement is excess weld metal, and the toe is where the weld face meets the base metal.

On an AWS welding symbol, information placed on the side of the reference line nearer the reader (below a horizontal reference line) applies to the weld on which side of the joint?

• a.The far side, away from the arrow
• b.Both sides equally regardless of placement
• c.Neither side; it is only supplementary data
• d.The arrow side of the joint✓

In the AWS symbol convention, weld symbols below the reference line specify the arrow side of the joint (the side the arrow points to), while symbols above the line specify the other side. This dual placement lets one symbol describe welds on both sides. Understanding arrow-side versus other-side placement is fundamental to reading drawings correctly.

Incomplete fusion in a weld is best described as:

• a.A gas pocket trapped in the solidifying weld metal
• b.A condition where the weld metal did not coalesce completely with the base metal or with adjacent weld beads✓
• c.Excess weld metal extending above the base metal surface
• d.A crater at the end of the weld bead

Incomplete fusion (lack of fusion) occurs when the molten weld metal fails to fuse with the base metal or preceding passes, leaving an unbonded interface. It typically results from insufficient heat, contamination, or poor technique. It is a serious discontinuity because it creates a plane of weakness. A gas pocket is porosity; excess metal is reinforcement; the depression is a crater.

Which nondestructive testing method can reliably detect internal (subsurface) volumetric discontinuities such as porosity and slag inclusions throughout the thickness of a weld?

• a.Radiographic testing (RT)✓
• b.Liquid penetrant testing (PT)
• c.Magnetic particle testing (MT)
• d.Visual testing (VT)

Radiographic testing passes X-rays or gamma rays through the weld to a film or detector, revealing internal volumetric flaws like porosity and slag as density changes on the image. PT only finds surface-breaking flaws; MT finds surface and slightly subsurface flaws in ferromagnetic material; VT only detects surface conditions. RT and ultrasonic testing are the primary volumetric methods for internal discontinuities.

Liquid penetrant testing (PT) is limited to detecting which type of discontinuity?

• a.Deep internal cracks well below the surface
• b.Discontinuities in any material regardless of surface condition
• c.Discontinuities that are open to the surface being examined✓
• d.Only discontinuities in ferromagnetic materials

PT relies on a liquid dye seeping into flaws by capillary action, then a developer draws it back out to form a visible indication. Because the penetrant must enter the flaw, only discontinuities that break the surface can be detected. Unlike MT, PT works on non-magnetic materials such as aluminum and stainless steel, but it cannot find subsurface flaws.

What is the primary personal-safety hazard associated with the arc rays produced during arc welding?

• a.Ingestion of shielding gas
• b.Excessive audible noise damaging hearing
• c.Contact with high-pressure hydraulic fluid
• d.Intense ultraviolet and infrared radiation that can burn skin and eyes (arc flash / arc eye)✓

The welding arc emits intense ultraviolet and infrared radiation that can cause painful arc eye (photokeratitis) and skin burns similar to severe sunburn. Proper protection includes a welding helmet with the correct shade lens, and covering exposed skin. Adjacent workers must also be shielded. This is one of the most common and preventable welding injuries.

Undercut is a weld discontinuity best described as:

• a.Weld metal that has flowed beyond the weld toe onto unfused base metal
• b.A groove melted into the base metal adjacent to the weld toe and left unfilled by weld metal✓
• c.Rounded cavities caused by trapped gas
• d.A depression at the termination of a weld bead

Undercut is a groove or channel melted into the base metal along the toe or root of a weld that is not filled by weld metal, reducing the effective cross-section and creating a stress riser. It is usually caused by excessive current, incorrect travel angle, or too-fast travel speed. Overflow onto unfused metal is overlap, gas cavities are porosity, and the end depression is a crater.

During visual inspection, a fillet weld gauge is used primarily to:

• a.Measure the leg size and check the throat/convexity of a fillet weld✓
• b.Detect internal porosity within the weld
• c.Measure the electrical resistance of the base metal
• d.Determine the chemical composition of the filler metal

A fillet weld gauge physically fits against the weld to measure leg length and assess whether the profile is convex, concave, or within tolerance. Visual inspection tools measure geometry and surface conditions, not internal or chemical properties. Internal flaws require RT or UT, and composition requires laboratory analysis. Selecting the correct gauge for the weld type is a core Part B skill.

When performing hands-on visual inspection of a weld, which practice best ensures accurate and consistent results?

• a.Judging acceptability by memory rather than referencing the specimen's acceptance criteria
• b.Inspecting only after the part is painted so the surface looks uniform
• c.Ensuring adequate lighting and using the specified gauges to measure against the acceptance criteria for that weld✓
• d.Measuring only the longest weld and assuming the rest are identical

Reliable visual inspection depends on adequate lighting, clean access to the weld, calibrated/appropriate gauges, and comparing each measured feature against the documented acceptance criteria. Judging from memory introduces error, painting hides discontinuities, and sampling only one weld ignores variation. Consistent, criteria-based measurement is what the Part B practical evaluates.

In the Part B practical, a weld replica (RMA-type gauge set) is most useful for:

• a.Chemically etching the weld to reveal grain structure
• b.Physically comparing a weld's profile and discontinuity size against standardized reference shapes and dimensions✓
• c.Measuring the voltage used during welding
• d.Recording the welder's certification number

Replica gauges and weld measuring gauges provide standardized reference profiles and precise scales so an inspector can compare a weld's actual contour, undercut depth, or reinforcement height to fixed dimensional references. They translate a visual observation into a measured value that can be judged against acceptance criteria. They do not perform etching, electrical measurement, or record-keeping functions.

A specimen book used in the Part B practical exam most directly provides:

• a.The welder's wage schedule
• b.A list of approved filler-metal suppliers
• c.The chemical analysis of each test plate
• d.The acceptance criteria and requirements the inspector applies to judge each weld replica✓

The Part B specimen book (Book of Specifications) contains the acceptance criteria, definitions, and requirements the candidate must apply to evaluate the weld replicas. The inspector measures each specimen and compares the result to these criteria to decide accept or reject. It functions as the rulebook for the practical, not a supplier list, wage sheet, or chemistry report.

When an inspector measures a discontinuity that falls exactly at the maximum size permitted by the acceptance criteria, the correct disposition is generally to:

• a.Accept it, because meeting the maximum allowable limit means it is within the criteria✓
• b.Reject it automatically, because any measurable discontinuity is a defect
• c.Ignore the measurement and rely on overall appearance
• d.Double the limit before comparing

Acceptance criteria define a maximum allowable value; a discontinuity that measures at or below that limit conforms and is accepted. A discontinuity only becomes a rejectable defect when it exceeds the allowable criteria. This distinction between a discontinuity (any interruption in the typical structure) and a defect (a rejectable discontinuity) is central to inspection judgment. Overall appearance never overrides measured criteria.

Before using a measuring gauge to accept or reject welds in the practical, the inspector should first:

• a.Bend the gauge to fit the weld
• b.Verify the gauge is the correct type and in good condition so its readings are valid✓
• c.Assume any available gauge will give the same reading
• d.File down the weld to make measurement easier

Valid measurements depend on using the correct, undamaged gauge appropriate for the feature being measured. A bent or wrong gauge yields false readings that lead to incorrect accept/reject decisions. An inspector never alters the weld to suit the tool. Selecting and verifying the proper instrument is a disciplined habit tested in Part B.

Which surface condition would an inspector evaluate purely by visual inspection in Part B, without any additional NDT equipment?

• a.Internal slag inclusions deep within the weld
• b.Subsurface lack of fusion between passes
• c.Surface-breaking cracks, undercut, overlap, and weld profile✓
• d.Hydrogen dissolved in the weld metal

Visual inspection detects surface conditions: surface cracks, undercut, overlap, excessive reinforcement, and overall weld profile and size. Internal flaws such as buried slag, subsurface lack of fusion, or dissolved gases require volumetric methods like RT or UT and cannot be judged by eye. Knowing the limits of VT keeps the inspector from over-claiming what visual results prove.

In the open-book Part C exam, the single most important skill for answering questions efficiently is:

• a.Memorizing every value so the book is never opened
• b.Reading each clause aloud to other candidates
• c.Guessing based on general welding experience without opening the code
• d.Quickly navigating the code's table of contents, index, and clause structure to locate the exact requirement✓

Part C is open-book, so success depends less on memorization and more on efficiently finding the governing clause, table, or figure using the code's table of contents and index. The exam rewards candidates who know how the document is organized and can locate and correctly apply the relevant requirement under time pressure. Guessing from experience risks missing code-specific values.

A Welding Procedure Specification (WPS) is best described as:

• a.A written document providing direction to the welder for making production welds in accordance with code requirements✓
• b.A record of a welder's personal certification test only
• c.A supplier's invoice for filler metal
• d.A drawing showing only the building's dimensions

A WPS is the written qualified procedure that tells the welder the essential variables (process, filler, joint design, preheat, current, etc.) for producing a code-compliant weld. It provides direction for production welding and is supported by a PQR that proves those parameters produce sound welds. It is not a personal certification, an invoice, or a structural drawing.

What is the primary relationship between a Procedure Qualification Record (PQR) and a Welding Procedure Specification (WPS)?

• a.The PQR replaces the WPS once welding begins
• b.The PQR documents the actual test results and data used to qualify and support the WPS✓
• c.The WPS and PQR are unrelated documents
• d.The PQR lists only the paint color of the finished structure

A PQR records the actual welding variables used to weld a test coupon and the results of the mechanical tests performed on it, demonstrating that the procedure produces sound, code-compliant welds. The WPS is then written and supported by that qualifying evidence. In short, the PQR proves it worked, and the WPS tells the welder how to repeat it. They are directly linked, not independent.

When a Part C question asks whether a particular weld is acceptable, the inspector should base the decision on:

• a.Personal preference about how the weld looks
• b.The most conservative value found anywhere on the internet
• c.The acceptance criteria specified in the applicable code for that weld type and loading condition✓
• d.The first number that appears in the code, regardless of context

Acceptance decisions must come from the acceptance criteria of the applicable code, matched to the correct weld type (e.g., fillet vs. groove) and loading condition (statically vs. cyclically loaded), because criteria can differ between them. The inspector must locate the correct clause or table rather than grabbing the first number or relying on opinion. Reading the context that governs which criteria apply is essential.

Why do many welding codes distinguish acceptance criteria for statically loaded versus cyclically loaded (fatigue) connections?

• a.Cyclically loaded members are more sensitive to stress risers, so their acceptance criteria for discontinuities are generally more stringent✓
• b.Statically loaded members never require any inspection
• c.The distinction only affects the paint specification
• d.Cyclic loading always uses a completely different metal

Members subject to repeated (cyclic) loading are prone to fatigue cracking that initiates at stress risers such as undercut, weld toes, or surface discontinuities. Codes therefore apply tighter acceptance limits for cyclically loaded connections than for statically loaded ones. Recognizing the loading condition tells the inspector which set of criteria to apply, which is a common Part C decision point.

If a Part C question refers to a defined term (for example, a specific weld feature) whose meaning affects the answer, the best practice is to:

• a.Assume the everyday dictionary meaning of the word
• b.Look up the term in the code's definitions section to apply the exact meaning intended by the code✓
• c.Ignore the term and answer from general knowledge
• d.Substitute a similar term from a different code

Codes contain a definitions/terminology section because terms often have precise technical meanings that differ from everyday usage and that determine which requirement applies. Confirming the code's own definition prevents misapplying a clause. Mixing terms from another code or using casual meanings can lead to the wrong acceptance decision. Precise reading of defined terms is a core open-book code skill.