AWS API 1104 Endorsement key terms

A circumferential butt weld joining two lengths of pipe, made in the field or yard, as opposed to a longitudinal seam weld produced at the pipe mill.

A circumferential butt weld joining two lengths of pipe, made in the field or yard, as opposed to a longitudinal seam weld produced at the pipe mill.

Any weld made to join pipe sections into the completed pipeline, including mainline girth welds, tie-ins, and fabrication welds, but excluding repair welds.

A girth weld that connects a newly welded section to previously installed pipe, often made in a confined excavation where fit-up and access are difficult.

A weld made to correct an unacceptable discontinuity in a completed weld, usually after removing the defect by grinding or gouging to sound metal.

Removal of a complete weld or pipe section that cannot be acceptably repaired, after which the pipe ends are re-beveled and a new girth weld is made.

The angled edge prepared on a pipe end so two ends can be fitted together and welded, with the angle, land, and root face controlling penetration and joint fit-up.

The flat, untapered portion of the beveled pipe end at the root of the joint, whose width affects root penetration and the risk of burn-through.

The clearance between the two pipe ends at the root of the joint before welding, set during line-up to allow root pass penetration without burn-through.

An internal or external device that aligns two pipe ends, holds the root gap, and maintains concentricity and proper bevel match during the root pass.

The misalignment between the internal or external surfaces of two joined pipe ends, measured as the offset and limited by specification because it concentrates stress.

The first weld pass, deposited at the joint root, which establishes penetration and fusion at the pipe bore and is the foundation for all later passes.

The pass deposited immediately after the root pass, usually with higher current, to burn out slag and ensure fusion before the fill passes are applied.

Any pass deposited after the hot pass and before the cap to build the weld up to the required thickness across the joint.

The final weld pass, which forms the visible crown on the outside surface and must meet specified height, width, and contour limits.

The exposed surface of the cap pass on the outside of the pipe, whose height above the pipe surface and profile are controlled by acceptance criteria.

A groove melted into the base metal at the toe of the weld and left unfilled, reducing wall thickness and acting as a stress concentration.

A localized area of base metal melted or damaged by an arc struck outside the weld joint, such as from a stray arc or improper grounding.

A planar discontinuity where weld metal fails to bond to the base metal or to a previous pass, often caused by low heat input or poor cleaning.

A discontinuity where the weld metal does not extend through the full joint thickness at the root, leaving an unbonded gap at the pipe bore.

Nonmetallic slag trapped between weld passes or between weld metal and base metal, typically from incomplete cleaning between passes.

Cavities in weld metal formed by trapped gas, appearing as rounded voids that may be scattered, clustered, or aligned along the weld.

A linear discontinuity caused by stress, hydrogen, or restraint that separates metal, and which is generally unacceptable regardless of size or location.

Delayed cracking caused by hydrogen absorbed during welding combined with residual stress and a hard microstructure, often appearing hours after welding.

Heating of the pipe before welding to a specified minimum temperature to slow cooling, limit hardness, and help prevent hydrogen cracking.

The temperature of the weld and adjacent base metal measured just before depositing the next pass, which must be kept within specified limits.

The energy delivered per unit length of weld, calculated from current, voltage, and travel speed, which strongly influences cooling rate and weld properties.

A written document that gives the required variables and ranges for making a production weld in accordance with a qualified procedure.

The documented record of the test weld and tests used to demonstrate that a welding procedure produces welds meeting the required properties.

A welding parameter, such as process, filler classification, or position, that if changed beyond specified limits requires requalification of the procedure.

A test weld made by an individual welder, examined to specified acceptance criteria, that demonstrates the welder's ability to produce sound welds.

The demonstrated skill of an individual welder, documented by qualification tests, with limits on the processes, positions, and pipe sizes covered.

The point at which a welder's qualification lapses, typically after a defined period without welding with the qualified process or after a failed test.

Examination of a test weld by cutting specimens and bending, tensile testing, or fracturing them to reveal discontinuities and confirm mechanical properties.

A destructive test in which a specimen is notched and broken open so the fracture face can be inspected for fusion, penetration, and inclusions.

A nondestructive method that passes radiation through a weld onto film or a detector, revealing internal discontinuities as density variations in the image.

A nondestructive method that sends high-frequency sound into the weld and interprets reflected echoes to detect and size internal planar discontinuities.

The specified limits that define whether a weld's discontinuities, dimensions, and profile are acceptable, expressed by type, size, and location.

The thickness of weld metal on the inside or outside surface beyond the base metal thickness, which must be limited to avoid stress concentration.