AWS Certified Welding Inspector — Fundamentals flashcards

The absence of the approved Welding Procedure Specification (WPS) in the final project documentation package is a critical deficiency, as it prevents the CWI from verifying that welding was performed to a qualified procedure, thereby hindering final project acceptance and certification.

• WPS is the blueprint for welding quality.
• Absence compromises traceability and compliance.
• Prevents final certification and sign-off.

Memory trick: No WPS, no proof, no project's roof.

The highest temperature allowed on a weld pass before the next pass is deposited. Exceeding it can negatively affect the mechanical properties, particularly toughness, of the weld and HAZ by altering cooling rates and grain structure.

• Crucial for controlling cooling rates.
• Impacts grain structure and mechanical properties.
• Essential for steels susceptible to HAZ embrittlement.

Memory trick: Too hot, too slow, toughness low.

A fillet weld whose leg length or throat dimension is less than the minimum size specified by the Welding Procedure Specification (WPS) or applicable code, constituting a non-conformance requiring formal action.

• Directly impacts weld strength.
• Must be documented as a non-conformance.
• Requires repair or engineering disposition.

Memory trick: Small weld, big problem, formal solution.

Ensuring that joint dimensions, such as root opening, groove angle, and fit-up, conform to the requirements of the Welding Procedure Specification (WPS) and applicable codes before welding commences.

• Critical for achieving sound welds.
• Prevents potential defects like lack of fusion or excessive distortion.
• Must be verified by the CWI or qualified personnel.

Memory trick: Measure twice, weld once, or it's a code violation.

Weld reinforcement (crown) that exceeds the maximum height specified by the WPS and applicable code. It creates stress concentrations at the weld toe, which can reduce fatigue life and impact the structural integrity of the weld.

• Geometric discontinuity at weld toe.
• Acts as a stress riser.
• Increases susceptibility to fatigue cracking.

Memory trick: Too high a crown, stress falls down hard.

Letters placed above NDE symbols on the reference line specify the sequence of examination relative to the welding operation.

• 'B' = Before welding.
• 'A' = After welding (default, often omitted).
• 'I' = During welding (interpass).

Memory trick: NDE letters tell you when, like a schedule.

A weld symbol placed below the reference line indicates that the weld is to be made on the arrow side of the joint.

• Below reference line = arrow side.
• Above reference line = other side.
• Both sides of reference line = both sides.

Memory trick: Arrow Down, Other Up, Both Everywhere

Porosity is a discontinuity in a weld caused by entrapped gas during solidification, appearing as spherical or elongated voids within the weld metal.

• Caused by gas entrapment during welding.
• Can appear on the surface or internally.
• Often looks like small, rounded holes.

Memory trick: Visual Weld Flaws: See the Gaps, Grooves, and Cracks.

The addition of small amounts (typically <0.1%) of elements like Niobium, Vanadium, or Titanium to High-Strength Low-Alloy (HSLA) steels to form fine precipitates and refine grain structure, thereby enhancing strength and toughness.

• Promotes precipitation hardening by forming carbides, nitrides, or carbonitrides.
• Refines grain size, which improves both strength and toughness.
• Allows for high strength at lower carbon content, improving weldability.
• Often used in conjunction with controlled rolling processes.

Memory trick: NioBium makes Strong Steels, No Big PWHT.

A change in an essential variable (e.g., filler metal, base metal, welding process, preheat) from the approved Welding Procedure Specification (WPS) typically requires re-qualification of the WPS or specific engineering approval before welding can proceed or continue.

• Essential variables impact weld mechanical properties.
• Changes necessitate WPS re-qualification or formal approval.
• CWI must stop work immediately when deviations occur.

Memory trick: Filler's new? Stop and review, or quality's askew.

Using a filler metal of a different classification than specified in the WPS is a deviation of an essential variable, fundamentally altering the weld's mechanical properties and making the weld non-compliant, requiring immediate cessation of welding.

• Electrode classification defines strength, chemistry, and usability.
• An essential variable, change requires WPS re-qualification.
• Can lead to welds with inadequate mechanical properties.

Memory trick: Wrong rod, wrong weld, properties foretold.

A metallurgical phenomenon in austenitic stainless steels where chromium carbides precipitate at grain boundaries due to exposure to specific temperatures (425-870°C), depleting adjacent areas of chromium and rendering them susceptible to intergranular corrosion.

• Occurs in austenitic stainless steels (e.g., 304, 316).
• Triggered by heating in the 425-870°C (800-1600°F) range.
• Leads to chromium depletion near grain boundaries.
• Results in susceptibility to intergranular corrosion ('weld decay').

Memory trick: High heat makes stainless steel 'Sense' the corrosion.

The root opening for a groove weld is the separation between the members at the root of the joint, indicated by a dimension placed below the groove weld symbol.

• Located directly below the groove weld symbol.
• Specifies the gap at the root of the joint.
• Crucial for proper weld penetration.

Memory trick: Root opening below, angle inside, like a blueprint's hidden show.

When a project's internal Quality Control (QC) plan deviates from or contradicts the mandatory requirements of an applicable welding code, the CWI's obligation is to ensure the code's requirements are met, requiring formal notification and resolution of the discrepancy.

• Codes override internal plans in case of conflict.
• CWI must uphold code compliance.
• Formal documentation and communication are essential.

Memory trick: Code is king, plan must sing its song.

When faced with client pressure to deviate from standard inspection practices for time or cost, a CWI's ethical response involves educating the client on risks, upholding quality standards, and proposing pragmatic, code-compliant alternatives rather than outright refusal or full compromise.

• Balance client needs with quality and safety.
• Education is key to explaining the 'why'.
• Seek solutions that maintain essential checks.

Memory trick: Educate, don't abdicate, safety's fate.

A Welder Qualification Report (WQR) is only considered valid and complete when all required information, including the signature of the authorizing welding engineer or CWI, is present and accurate, signifying official approval.

• Essential for legal and contractual compliance.
• Ensures welder competency is officially verified.
• Missing signatures invalidate the report.

Memory trick: No sign, no go, qualifications flow.

The arrangement and size of crystalline grains within the solidified weld metal, which significantly influences mechanical properties.

• Influenced by welding parameters, especially cooling rate.
• Coarse, columnar grains are common in fusion zones with slow cooling.
• Fine, equiaxed grains are generally preferred for better mechanical properties.
• Grain structure affects strength, ductility, and toughness.

Memory trick: Slow and steady wins the race, but makes coarse grains.