CWE key terms

A written document that gives the welder the specific variables, ranges, and techniques needed to make a production weld that complies with a qualified procedure.

The documented record of the test weld made to qualify a welding procedure, listing actual variables used and the destructive test results that proved the procedure sound.

A welding parameter that, if changed beyond the code-permitted range, invalidates the procedure qualification and requires requalification, such as filler classification, preheat, or heat input.

A procedure parameter that may be changed without requalifying the procedure because it does not affect the mechanical properties of the completed weld.

A test demonstrating that an individual welder can produce sound welds to a given procedure, recorded on a qualification test record and valid for defined positions and processes.

The energy delivered to the weld per unit length, calculated from arc voltage, current, and travel speed; excessive heat input can degrade toughness and cause distortion.

The application of heat to the base metal before welding to slow cooling, reduce cracking risk, and drive off moisture from the joint area.

The temperature of the weld and surrounding base metal measured immediately before the next pass is deposited, kept within limits set by the procedure.

Delayed cracking in steel caused by dissolved hydrogen combined with restraint and hard microstructure; controlled through preheat, low-hydrogen consumables, and dry storage.

An arc welding process in which a covered electrode is consumed and its coating generates shielding gas and slag to protect the molten weld pool.

An arc welding process using a non-consumable tungsten electrode and separately supplied shielding gas, often with added filler rod, giving precise control on thin sections.

A gas or gas mixture supplied to the arc to exclude atmospheric oxygen and nitrogen from the molten weld metal and prevent porosity and embrittlement.

The non-consumable electrode in gas tungsten arc welding, selected by type and diameter to carry the required current without melting or contaminating the weld.

The standardized designation (for example, an AWS electrode classification) that identifies a consumable's strength, position capability, coating, and current type.

The controlled drying and holding of covered electrodes at specified temperatures to keep moisture, and therefore diffusible hydrogen, out of the weld.

A code designation describing whether a groove weld is made flat, horizontal, vertical, or overhead, which determines the skill level a welder must qualify for.

The rate at which the arc moves along the joint; it directly affects bead size, penetration, and heat input per unit length.

The depth to which the weld metal fuses into the root of the joint or the base metal beneath the surface.

The first weld pass deposited at the bottom of a groove, which establishes the root bead and largely controls penetration and backing requirements.

Material placed behind the root of a joint to support molten weld metal and control penetration; it may be permanent or removable.

A discontinuity in which weld metal fails to bond with the base metal or with a previous pass, usually caused by low heat, fast travel, or poor technique.

Nonmetallic slag trapped in weld metal or along the fusion line, typically from incomplete cleaning between passes or poor arc manipulation.

Cavities in solidified weld metal formed by trapped gas, often linked to moisture, contamination, or inadequate shielding.

A groove melted into the base metal at the weld toe or root that is left unfilled, reducing the effective thickness of the joint.

Unwanted change in the shape or dimensions of a welded assembly caused by nonuniform heating, cooling shrinkage, and residual stress.

Internal stress locked into a weldment after cooling because restrained contraction prevents the metal from returning to a stress-free condition.

The planned order of passes and joints used to balance heat and shrinkage, limiting distortion and residual stress in the finished structure.

A drawing notation combining a reference line, arrow, and standardized elements to specify weld type, size, length, and location on a joint.

The optional part of a welding symbol at the far end of the reference line, used to carry process, specification, or reference information.

Examination of a weld by eye, aided by lighting, mirrors, and gauges, to find surface discontinuities and verify size and profile before other testing.

A hand tool set used to measure fillet leg and throat size, weld reinforcement, undercut depth, and joint misalignment against acceptance limits.

Examination that cuts or breaks a test weld to reveal internal quality, including bend, tensile, and impact tests used to qualify procedures and welders.

A qualification test in which a specimen is bent around a specified radius to expose lack of fusion, porosity, or other defects on the tension surface.

A cross-section of a weld polished and etched with acid to reveal penetration, fusion, bead shape, and internal discontinuities for examination.

Inspection methods such as ultrasonic, radiographic, magnetic particle, and dye penetrant testing that reveal defects without damaging the weld.

The base metal adjacent to the weld that is altered by welding heat but not melted, where properties and microstructure can change significantly.

Two common crystal structures of steel: body-centered cubic ferrite, relatively soft and magnetic, and face-centered cubic austenite, formable and nonmagnetic.

Cracking that occurs while the weld is hot and shrinking, often along centerlines where low-melting constituents or high restraint concentrate strain.

The helmet, filter lens, gloves, leathers, and respiratory protection worn to shield the welder from arc radiation, spatter, fumes, and burns.

Local exhaust ventilation that captures welding smoke at the arc before it reaches the welder's breathing zone, reducing exposure to metal fume.

A written authorization confirming fire watches, combustible clearance, and precautions are in place before welding, cutting, or grinding begins.