AWS Certified Welding Inspector — Fundamentals flashcards

AWS D1.1 specifies limits for undersized fillet welds, typically allowing a maximum undersize of 1/16 inch, but this reduction must also not exceed 10% of the specified weld size.

• Both absolute and percentage limits must be met.
• Undersizing can reduce weld strength.
• CWI must use a fillet weld gauge for accurate measurement.

Memory trick: Absolute AND Percent - Both Must Pass.

A metallurgical phenomenon in austenitic stainless steels where chromium carbides precipitate at grain boundaries upon exposure to elevated temperatures (e.g., 800-1500°F). This depletes adjacent regions of chromium, making them susceptible to intergranular corrosion.

• Occurs in the HAZ during welding due to excessive heat input.
• Common in standard grades like 304; reduced in 'L' grades (304L) due to lower carbon.
• Leads to loss of corrosion resistance, especially in aggressive environments.
• Mitigated by using low-carbon 'L' grades, stabilized grades (321, 347), or solution annealing.

Memory trick: Sensitization: Heat steals Chromium, then rust eats the grain boundaries.

A CWI's responsibility to ensure that all required project documentation, including NDT reports, material certifications, and WPS records, is complete and accurate before final acceptance or reporting.

• Essential for full traceability and compliance.
• Missing documents invalidate the inspection process.
• CWI must halt final approval until documentation is complete.

Memory trick: No Missing Pages, No Final Stamp.

Cracks that form in the weld metal during solidification, typically along grain boundaries. Caused by tensile stresses acting on weak, low-melting-point liquid films at the grain boundaries.

• Occurs at high temperatures during or immediately after solidification.
• Associated with impurities like sulfur and phosphorus.
• Affected by weld metal composition, joint restraint, and weld shape.
• Often appears as centerline cracks in the weld bead.

Memory trick: Hot cracks happen when low-melt goop gets stuck in the grain gaps.

Essential variables in a WPS are parameters that, if changed beyond specified limits, are considered to affect the mechanical properties of the weld and therefore require requalification of the WPS.

• Changes require WPS requalification.
• Examples: base metal P-number, filler metal F-number, preheat (significant changes).
• Non-essential variables do not require requalification.
• Supplementary essential variables apply to impact-tested materials.

Memory trick: Essential changes 'E'nsure 'E'valuation, non-essential 'N'ever 'N'eed 'N'ew tests.

AWS D1.1 specifies the range of positions a welder is qualified to weld based on the test position performed, with certain groove tests qualifying for specific fillet positions.

• A 3G (vertical groove) test qualifies for 1F, 2F, 3F fillet welds.
• A 4F (overhead fillet) test is a separate qualification.
• Qualification ranges are detailed in AWS D1.1 tables.

Memory trick: Grooves Don't Always Cover All Fillets.

The ethical obligation of a CWI to refuse to perform or allow any action that deviates from specified codes, standards, or project requirements, even under pressure.

• Prioritizes safety and quality over expediency or client pressure.
• Requires clear communication of reasons for refusal.
• Protects the CWI's professional integrity and certification.

Memory trick: Standards First, Always Say No to Shortcuts.

The process of removing slag, spatter, and other contaminants from the surface of a weld pass before depositing subsequent passes, crucial for preventing defects.

• Ensures proper fusion between weld passes.
• Prevents slag inclusions and porosity.
• Often a code requirement, even if not detailed in WPS.

Memory trick: Clean Passes Ensure Strong Welds.

A phenomenon in certain alloy steels where toughness is severely reduced when the material is exposed to elevated temperatures (typically 750-1100°F or 400-600°C) for extended periods. It is caused by the segregation of impurity elements to grain boundaries.

• Occurs in the temper embrittlement range, often during PWHT or service.
• Leads to intergranular fracture and increased ductile-to-brittle transition temperature.
• Caused by impurity elements like P, Sn, Sb, As.
• Molybdenum additions are used to mitigate it.

Memory trick: Temper Embrittlement: Phosphorous is the primary poison at the grain boundary party.

A formula used to estimate the hardenability and weldability of a steel, particularly its susceptibility to hydrogen-induced cracking (cold cracking). It accounts for the effect of various alloying elements as if they were carbon.

• Higher CE indicates higher hardenability and increased risk of cold cracking.
• Commonly used formulas include the IIW formula (International Institute of Welding).
• Used to determine appropriate preheat and post-weld heat treatment requirements.
• Typically calculated by: CE = C + Mn/6 + (Cr+Mo+V)/5 + (Ni+Cu)/15.

Memory trick: When CE is high, think HOT (preheat) and SLOW (cooling) to keep cracks low.

A condition where the leg size of a fillet weld is smaller than that specified in the WPS or required by the applicable code, potentially reducing strength.

• Typically a defect if exceeding code-specified tolerance.
• AWS D1.1 has specific limits for undersize, often 1/32 inch for smaller fillets.
• Requires documentation and disposition (repair, accept-as-is with engineering approval, or reject).

Memory trick: Measure the weld, compare to spec, if it's small, it's a defect.

Undercut is a groove melted into the base metal adjacent to the toe or root of a weld and left unfilled by weld metal.

• Located at the weld toe or root.
• A groove in the base metal.
• Left unfilled by weld metal.

Memory trick: A 'cut' at the 'toe' is an 'undercut'.

The CWI's responsibility to monitor and ensure that all welding parameters (current, voltage, travel speed, gas flow) remain within the ranges specified by the WPS during welding.

• Deviations can lead to critical weld defects.
• Requires continuous monitoring, often with data loggers.
• Immediate corrective action is necessary for non-compliance.

Memory trick: Parameters Must Be Stable, Or Stop.

A conflict of interest arises when a CWI's personal interests (e.g., financial, familial) could improperly influence, or appear to influence, their professional judgment or actions.

• Must avoid situations compromising impartiality.
• Direct financial interest is a clear conflict.
• Ethical duty to decline assignments with unavoidable conflicts.
• Disclosure may not be sufficient for severe conflicts.

Memory trick: Financial ties are 'F'atal to 'F'airness; 'F'lee from 'F'lawed 'F'abricators.

A heat treatment process applied to hardened steel to reduce brittleness and improve toughness and ductility. It involves reheating quenched steel to a temperature below the lower critical temperature, followed by cooling.

• Always follows a hardening (quench) process.
• Reduces internal stresses and transforms brittle martensite.
• Temperature and time determine final properties.
• Crucial for applications requiring both strength and impact resistance.

Memory trick: Hardening makes it tough, but Tempering makes it just right.

A type of cold cracking that occurs in the weld metal or heat-affected zone (HAZ) of susceptible steels, often hours or days after welding. It is caused by the synergistic effect of diffusible hydrogen, high tensile stresses, and a brittle microstructure.

• Also known as cold cracking or delayed cracking.
• Common in high-strength steels and steels with high carbon equivalent.
• Hydrogen sources include moisture in consumables, base metal, or atmosphere.
• Prevented by preheating, low-hydrogen consumables, and post-weld heat treatment.

Memory trick: HIC: HAZ cracks, High strength, Hours delayed, Hydrogen's bad play.

A CWI's ethical duty to report any observed deviations from project specifications, codes, or quality control plans to the appropriate management or client representatives.

• Ensures project integrity and safety.
• Protects the CWI from liability.
• Applies to personnel qualifications, materials, and procedures.

Memory trick: Report Deviations, Keep Standards High.

The specified maximum height above the base metal surface allowed for a groove weld's reinforcement, crucial for preventing stress concentrations and ensuring proper fit-up for subsequent operations.

• Excessive reinforcement can act as a stress riser.
• Limits are specified in WPS and governing codes (e.g., AWS D1.1).
• Must be ground down if exceeding specified maximums.

Memory trick: Too Tall Reinforcement Must Fall.

Careful control of interpass temperature is crucial for High-Strength Low-Alloy (HSLA) steels to prevent both hydrogen cracking (if too low) and degradation of mechanical properties (if too high).

• Impacts microstructure and mechanical properties (strength, toughness).
• Excessive heat can lead to grain coarsening in HAZ.
• WPS must specify appropriate limits for the specific HSLA grade.

Memory trick: Goldilocks Temperature: Not Too Hot, Not Too Cold.

The CWI's responsibility to verify that welding consumables, especially low-hydrogen electrodes, are stored according to manufacturer's recommendations and relevant codes (e.g., AWS A5.1) to prevent moisture absorption and ensure weld quality.

• Moisture in electrodes causes hydrogen cracking.
• Low-hydrogen electrodes require dry, heated storage.
• Compromised consumables must be quarantined or reconditioned.

Memory trick: Wet Rods Mean Bad Welds – Quarantine!

The specific range of materials, processes, positions, and filler metals a welder is certified to weld based on their qualification test.

• Qualifications are not always universal; they are often limited.
• Project specifications can impose stricter qualification requirements than standard codes.
• CWI must verify welder qualification precisely matches assigned work.

Memory trick: Qualification's scope: Match the welder to the weld, or the job's denied.

A CWI is responsible for enforcing adherence to the project's Quality Control Plan, ensuring all specified inspections and testing are performed at the mandated rates and methods.

• QC Plan specifies inspection types and frequencies.
• Non-compliance can compromise safety and quality.
• CWI must halt non-conforming work.
• Documentation alone is insufficient for critical deviations.

Memory trick: When the 'Q'uality 'C'ontrol 'P'lan is 'P'oorly followed, 'P'revent 'P'roblems by 'P'ausing 'P'roduction.

A groove melted into the base metal adjacent to the toe or root of a weld and left unfilled by weld metal. It reduces the effective thickness of the base metal at the weld joint.

• Caused by excessive current, too long an arc, or incorrect electrode angle.
• Acts as a stress concentrator, potentially leading to fatigue or brittle fracture.
• Can be detected by visual inspection.
• AWS D1.1 (Structural Welding Code – Steel) specifies limits for undercut.

Memory trick: Undercut: A 'cut' (groove) 'under' the weld.

A CWI's pre-weld responsibilities include verifying compliance with the WPS regarding materials, equipment, and procedures before welding commences.

• Verify material specifications and storage.
• Check equipment calibration and functionality.
• Confirm welder qualification and procedure adherence.

Memory trick: When something's wrong, Stop, Check, and Correct before it gets worse.

Verifying that Non-Destructive Testing (NDT) personnel hold the specific certifications (e.g., ASNT SNT-TC-1A Level II/III) required by project codes and specifications.

• Crucial for validity and acceptance of NDT results.
• Different codes/standards specify different qualification bodies.
• CWI must verify certification against project requirements.

Memory trick: NDT Certs Must Match Specs Exactly.

Verifying that all welding parameters (e.g., travel speed, voltage, amperage) are strictly followed as prescribed in the approved Welding Procedure Specification (WPS) during the actual welding operation.

• Deviation from WPS can compromise weld quality and mechanical properties.
• CWI must monitor and enforce WPS parameters.
• Immediate correction is required for non-compliance.

Memory trick: During the weld, watch the specs, don't let the process get off track.

A Non-Conformance Report (NCR) is a formal document used to record details of materials, products, or processes that do not meet specified requirements or standards.

• Documents deviation from code/WPS.
• Includes defect description, location, and severity.
• References applicable code/standard violation.
• Outlines proposed corrective and preventive actions.

Memory trick: Critical defects demand a 'C'omprehensive 'C'ode-compliant 'C'onformance Report.

A visual sign of a defect that is longer than it is wide, often indicative of a crack, which requires further investigation, especially in critical applications.

• Can signify a crack, which is a severe defect.
• Requires further NDE (PT/MT) to confirm nature and depth.
• Critical in pressure retaining components (e.g., ASME B31.3).

Memory trick: See a Line? Further Define!

A condition where a quenched and tempered (Q&T) steel is exposed to temperatures higher or for longer durations than intended during a tempering process, or during subsequent thermal cycles like welding. It results in a loss of designed strength and hardness.

• Occurs when tempering temperature is too high or time too long.
• Leads to coarsening of carbides and decomposition of martensite.
• Reduces tensile strength, yield strength, and hardness.
• Can happen in the HAZ of Q&T steels if interpass temperatures are exceeded.

Memory trick: Too much heat on Q&T steel means over-tempering, making it weak.

A CWI's paramount ethical responsibility is to ensure that all welding activities and completed welds strictly adhere to the specified codes, standards, and WPS, without compromise.

• Uphold the integrity of the code.
• Reject non-conforming work.
• Prevent acceptance of defective welds.
• Act without bias or undue influence.

Memory trick: Code Compliance is the CWI's 'C'ore 'C'ommitment, no 'C'ompromise.

The ability of a material to absorb energy and plastically deform without fracturing. It indicates a material's resistance to crack propagation under impact or other dynamic loading conditions.

• Measured by impact tests (e.g., Charpy V-notch).
• Combines strength and ductility.
• Crucial for components subjected to impact or dynamic loads.
• Can be affected by temperature, microstructure, and stress concentration.

Memory trick: Toughness: Take a hit, bend, don't break!

The critical role of accurate and detailed records (WPS, welder IDs, inspection reports) in ensuring quality, safety, and traceability throughout a project's lifecycle.

• Provides a historical record of all welding activities.
• Essential for quality assurance and control.
• Enables root cause analysis in case of failures.

Memory trick: Records Connect Past to Future.

Interpass temperature is the temperature of the weld area before the next welding pass is deposited. It is critical for controlling cooling rates, preventing cracking, and ensuring proper metallurgical properties.

• Must be within WPS-specified range.
• Too high can lead to grain growth or hot cracking.
• Too low can lead to hydrogen-induced cracking.
• Monitored during welding inspection.

Memory trick: Hot welds need to 'Cool It!' before the next pass, or quality will 'Fail It!'

API 1104 mandates specific tolerances for pipe fit-up, including misalignment, before welding. The CWI must ensure these tolerances are met to prevent weld defects and ensure structural integrity.

• Girth weld fit-up is critical.
• Excessive misalignment causes defects.
• CWI verifies compliance before welding.
• Requires correction of non-compliant fit-up.

Memory trick: Misaligned pipes 'M'ust be 'M'ade 'M'eet to 'M'inimize 'M'istakes.

AWS D1.1 specifies the range of qualification for welders based on the type and position of the test weld performed.

• Groove weld qualifications often cover certain fillet weld positions.
• A 3G qualification covers 1F, 2F, and 3F fillet welds.
• Qualification ranges depend on the specific test position and joint type.

Memory trick: Groove welds are the 'G'ateway to many 'F'illet positions.

A form of embrittlement occurring in duplex and other stainless steels when exposed to temperatures typically between 1200-1700°F (650-925°C). It involves the formation of a brittle, chromium and molybdenum-rich intermetallic phase (sigma, σ), leading to severe loss of ductility, toughness, and corrosion resistance.

• Forms from ferrite in duplex stainless steels.
• Time-temperature dependent; longer exposure or higher temperatures increase formation.
• Causes a significant increase in hardness and decrease in impact strength.
• Mitigated by controlling heat input, interpass temperature, and rapid cooling after welding.

Memory trick: Duplex steels get Sigma-sad when too hot, losing their balance.

A critical CWI responsibility to verify that joint preparation, fit-up, and dimensions comply with the Welding Procedure Specification (WPS) before welding begins.

• Ensures proper fusion and penetration.
• Prevents defects like lack of fusion or excessive distortion.
• Includes checking root opening, groove angle, and alignment.

Memory trick: Joint Dimensions Must Align Perfectly with WPS.

A weld discontinuity consisting of gas pockets entrapped within the solidified weld metal. It appears as spherical or elongated voids, singly or in clusters.

• Caused by gas entrapment during solidification.
• Can weaken the weld and act as stress concentrators.
• Sources include moisture, contaminants, inadequate shielding gas, or arc instability.
• Can be detected visually or with radiographic testing.

Memory trick: Remember, 'P' for Porosity means 'P' for Pockets of gas.

The process of raising the temperature of the base metal immediately prior to welding. It reduces the thermal gradient and slows the cooling rate of the weld and HAZ.

• Reduces hydrogen-induced cracking risk.
• Prevents brittle microstructure formation.
• Minimizes distortion and residual stresses.
• Critical for high-hardenability steels and thick sections.

Memory trick: Preheating's main goal is to SLOW the cooling, not just warm it up.

A type of cracking that occurs in the weld metal during the final stages of solidification. It appears as fine, interconnected cracks that typically follow the dendritic grain boundaries.

• Also known as hot cracking.
• Caused by tensile stresses acting on low-melting-point liquid films at grain boundaries.
• Aggravated by high restraint, weld shape, and presence of impurities (S, P).
• Occurs in the weld metal itself, not typically the HAZ or base metal.

Memory trick: Cracks: Hot on dendrites, Cold from H, Lamellar in base, Reheat in oven.

Preheat temperature is verified using temperature-indicating crayons by observing their melt behavior on the base metal adjacent to the weld joint, ensuring the specified minimum temperature is reached.

• Crayon melts at a specific temperature.
• Apply 1-3 inches from weld joint.
• Observe the crayon melt to confirm minimum temperature.
• Avoid contaminating joint with crayon.

Memory trick: Mark 'N' melt 'N'ear the 'N'eck of the weld.

A Welding Procedure Specification (WPS) is a formal written document describing welding procedures, providing direction for welders to make sound and quality production welds as per code requirements.

• Written instruction for welding.
• Ensures consistent weld quality.
• Specifies essential, non-essential, and supplementary essential variables.
• Must be qualified through PQR (Procedure Qualification Record).

Memory trick: WPS: 'W'hen 'P'rocedures are 'S'ound, 'S'uccess is 'S'ure.

A heat treatment applied to a weldment after welding to improve its properties. Common purposes include stress relief, tempering, and promoting hydrogen diffusion to prevent cracking.

• Reduces residual stresses, minimizing distortion and fatigue failure.
• Tempering effect on HAZ improves toughness and ductility.
• Facilitates hydrogen removal, preventing hydrogen-induced cracking.
• Can also alter microstructure and mechanical properties across the weldment.

Memory trick: PWHT: Relieves stress, tempers, and lets the H-bomb diffuse out.

A circle at the junction of the reference line and the arrow indicates that the weld is to extend completely around the joint.

• Always a circle.
• Located at arrow/reference line junction.
• Applies to entire joint perimeter.

Memory trick: Circle means 'complete circuit', flag means 'far field'.

The blurring or lack of definition in a radiographic image caused by the finite size of the radiation source's focal spot.

• Formula: Ug = (F * t) / (SFD - t).
• F = effective focal spot size, t = part thickness, SFD = source-to-film distance.
• Minimizing Ug improves image quality and detectability of small discontinuities.

Memory trick: Sharp images need small spots, far sources, and thin parts.

On a radiograph, porosity appears as small, dark, rounded or elliptical indications, often randomly distributed, due to gas entrapment within the weld metal.

• Less dense than surrounding material, allowing more radiation passage.
• Can be isolated, clustered, or uniformly scattered.
• Shape helps differentiate from other volumetric discontinuities like slag.

Memory trick: Round dark spots mean gas, bright spots mean heavy mass.

The amount of magnetic particles (by volume) suspended in the carrier fluid for wet MT.

• Crucial for clear, sharp indications.
• Too high: fuzzy, smeared indications, high background.
• Too low: weak or missed indications.
• Checked regularly using a centrifuge tube.

Memory trick: Fuzzy indications mean too many particles, like too many sprinkles on a donut.

A safety procedure used to ensure that dangerous machines are properly shut off and not able to be started up again prior to the completion of maintenance or service work.

• Physically isolates energy sources.
• Prevents accidental startup.
• Mandated by OSHA for hazardous energy control.

Memory trick: Lock it out, tag it tight, keep the power from seeing the light.

For butt joints, NDE symbols placed directly on the reference line generally indicate that the entire weld or joint is to be inspected by the specified method.

• Applies to the entire weld length.
• Does not distinguish between arrow side or other side for butt joint inspection scope.
• Specific inspection extent (e.g., spot, intermittent) would be indicated by additional symbols or notes in the tail.

Memory trick: Reference line for NDE means 'all-around' for the weld.

A procedure for safely extracting individuals from confined spaces when an emergency occurs, emphasizing trained personnel and proper equipment.

• Do not attempt untrained rescue.
• Activate emergency plan immediately.
• Ensure rescuers are properly equipped and trained.

Memory trick: When a space is tight and a person is down, call the pros from your safety town.

A penetrant that requires a separate emulsifier to make it water-washable, providing controlled removal.

• Offers high sensitivity for detecting very fine discontinuities.
• Emulsifier dwell time is critical for proper removal.
• Used for critical applications where maximum sensitivity and control are needed.

Memory trick: Post-emulsifiable: 'P' for Precision, 'E' for Emulsifier, 'C' for Control.

The abbreviation 'PJP' in the tail of a welding symbol indicates a Partial Joint Penetration groove weld.

• Tail contains supplementary information.
• 'PJP' stands for Partial Joint Penetration.
• Indicates incomplete penetration through joint thickness.

Memory trick: The tail tells the 'tale' of extra details.

A Ground Fault Circuit Interrupter (GFCI) rapidly detects current leakage to ground and trips the circuit, preventing electrocution, especially crucial with damaged cords.

• Detects ground faults (current leakage).
• Trips circuit rapidly to prevent shock.
• Essential safety device in wet/hazardous environments.

Memory trick: Frayed wires and no GFCI, a deadly shock is standing by.

In welding symbols, the arrow side refers to the side of the joint where the arrow points, while the other side is the opposite side. Different weld details can be specified on each side.

• Information below the reference line applies to the arrow side.
• Information above the reference line applies to the other side.
• Allows for distinct weld specifications on each side of a joint.

Memory trick: Arrow points, other side opposes, reference line divides.

When a single-bevel or single-J groove weld symbol is on the arrow side of the reference line, the preparation (beveling) is on the member the arrow points to.

• Arrow side symbol = arrow side member prep.
• Other side symbol = other side member prep.
• Ensures proper joint geometry.

Memory trick: The arrow points to the part that gets the cut.

In Ultrasonic Testing (UT), wavelength (λ) is calculated by dividing the wave velocity (V) by its frequency (f) (λ = V/f). Shear wave velocity is typically half of longitudinal wave velocity.

• λ = V/f.
• Velocity units must match frequency units (e.g., in/µs and MHz).
• Shear wave velocity (Vs) ≈ 0.5 * Longitudinal wave velocity (Vl).
• Wavelength affects resolution and penetration.

Memory trick: Velocity is how fast, Frequency is how often, Wavelength is how long.

When an NDE symbol is centered on the reference line, it indicates that the examination applies to both sides of the weld, particularly for symmetrical joints.

• Centered on reference line.
• Applies to both sides.
• Common for symmetrical welds (e.g., double groove).

Memory trick: Centered means 'complete coverage', like a balanced scale.

Discontinuities in a material, such as cracks, alter the flow of eddy currents, causing changes in both the amplitude and phase of the measured electrical signal.

• Amplitude change relates to the depth/size of the flaw.
• Phase change relates to the type, depth, and orientation of the flaw.
• Experienced operators interpret these changes to characterize discontinuities.

Memory trick: Amplitude is size, Phase is depth, both mean a flaw's adept.

The process of connecting electrical equipment to the earth, providing a low-resistance path for fault currents to safely dissipate, preventing electric shock.

• Protects against electric shock.
• Requires a dedicated ground wire.
• Essential for high-voltage equipment.

Memory trick: Three prongs for safety, one for the ground, keeping all the danger safely unbound.

Eddy Current Testing (ET) detects discontinuities and material variations by measuring changes in the impedance of a probe coil as induced eddy currents in a conductive material are disrupted by flaws or property changes.

• Based on electromagnetic induction.
• Alternating current in probe induces eddy currents.
• Discontinuities disrupt eddy current flow.
• Disruption changes probe coil impedance.

Memory trick: Each NDE has its own physics trick.