CWB Welding Inspector Level 3 flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Heat input formula

Heat input in kJ/mm equals voltage times amperage times 60, divided by travel speed in mm per minute times 1000. Increasing travel speed lowers heat input.

Spray transfer GMAW

Metal transfers as fine axial droplets above a transition current, requiring argon-rich shielding and giving high heat input; it is limited to flat and horizontal positions.

DCEN in GTAW steel

Direct current electrode negative concentrates about two-thirds of the arc heat at the workpiece, producing deep penetration and a cool tungsten; it is standard for carbon and stainless steel.

Submerged arc welding characteristics

An arc buried under granular flux using currents up to about 1500 A, giving high deposition and deep penetration; normally restricted to flat and horizontal positions.

Duty cycle definition

The percentage of a ten-minute period that a power source can operate at a stated current without overheating; 60 percent at 300 A allows six minutes of arcing.

Arc blow cause

Magnetic deflection of the arc, most common with direct current and high amperage near joint ends; remedies include alternating current, shorter arc, backstep and relocating the work lead.

E7018 electrode storage

A basic low-hydrogen electrode held in a heated oven near 120 degrees Celsius and redried after moisture exposure, preventing hydrogen from entering the weld.

Carbon equivalent formula

CE equals carbon plus manganese divided by six, plus chromium, molybdenum and vanadium divided by five, plus nickel and copper divided by fifteen; higher values raise cracking risk.

Hydrogen-assisted cracking conditions

Requires dissolved hydrogen, a hard susceptible microstructure, tensile stress and a temperature near ambient acting together; preheat and low-hydrogen consumables reduce the risk.

Sensitization of austenitic stainless

Chromium carbides precipitate at grain boundaries when 300-series stainless is held between roughly 425 and 815 degrees Celsius, leaving chromium-depleted zones prone to intergranular corrosion.

Basic flux cored wire

A calcium-fluoride based flux system giving low hydrogen and good toughness, but poorer bead appearance and more difficult out-of-position welding than rutile types.

CSA W47.1 scope

A Canadian standard for certification of companies performing fusion welding of steel structures; it covers organization capability, welding engineers, supervisors and welder qualification.

AWS D1.1 prequalified WPS

A procedure using joints detailed in the code and variables within prescribed limits needs no mechanical testing, but must still be written, complete and followed.

Essential variable

A welding parameter, such as process or filler classification, whose change beyond permitted limits requires requalification of the welding procedure specification.

CSA W178.2 inspector levels

A Canadian certification standard for welding inspectors with three levels; higher levels require more experience and education and carry wider supervision and approval authority.

ASME IX P-number

A grouping of base metals with similar weldability and mechanical properties; a procedure qualified on one P-number may cover other metals within the same group.

Procedure qualification record purpose

Documents the variables and test results proving a welding procedure produces sound welds with specified mechanical properties; it supports the WPS but is not a work instruction.

Guided bend test

A transverse weld specimen bent 180 degrees around a specified radius to expose surface and near-surface discontinuities in the weld and heat-affected zone.

Welder performance qualification

Demonstrates that an individual welder can produce sound welds to a code; it is specific to process, position and thickness range and requires periodic renewal.

Six G test position

A pipe fixed at 45 degrees and not rotated, requiring flat, vertical, overhead and horizontal welding; it qualifies the widest range of pipe positions.

WPS availability requirement

The written welding procedure must be accessible to the welder and inspector at the work location, and production welding must follow it exactly.

Penetrant testing dwell time

The period penetrant remains on the cleaned surface, commonly 5 to 10 minutes, allowing entry into surface-breaking discontinuities before removal and development.

Magnetic particle testing current type

Alternating current detects mainly surface discontinuities, while direct or rectified current can reveal slightly deeper near-surface defects in ferromagnetic materials.

Radiographic image quality indicator

A wire or hole type penetrameter placed on the part to verify that a radiograph has adequate sensitivity to detect the required discontinuity size.

Fillet weld throat measurement

For a 45-degree equal-leg fillet, theoretical throat equals 0.707 times the leg length; actual throat is reduced by convexity or increased by concavity.

Ultrasonic angle beam inspection

A refracted shear wave launched at an angle detects planar defects such as lack of fusion and cracks oriented roughly perpendicular to the weld surface.

Geometric unsharpness

Blurring on a radiograph caused by the finite source size; it decreases with a larger source-to-object distance and film placed close to the part.

Quality assurance versus control

Quality assurance covers planned system activities that prevent defects; quality control covers inspection and testing that detect defects in the finished product.

Inspection and test plan

A document listing inspection and test activities, acceptance criteria, responsible parties and hold or witness points in the sequence of production.

Hold point definition

A stage in production where work cannot continue until the designated inspector has verified the activity and recorded formal approval.

Corrective action versus containment

Containment prevents defective product from progressing; corrective action identifies and eliminates the root cause so that the nonconformity does not recur.

Audit nonconformity

A documented finding that a quality system or standard requirement has not been met; it requires a response, root cause investigation and verification of corrective action.