This European Standard specifies the requirements for producing and inspecting girth, branch and fillet welds in the pipeline part of pipeline transportation systems for the petroleum and natural gas industries meeting the requirements of ISO 13623.On-land supply systems used by the gas supply industry are excluded from the scope of the International Standard.This European Standard is applicable to the requirements for welding of carbon and low-alloy steel pipes. Application is restricted to pipes with a diameter of 20 mm and larger and wall thickness of 3 mm or more, and a specified minimum yield strength of 555 MPa or less. It is also applicable to welding into pipelines, items such as spools, risers, launchers/receivers, fittings, flanges and "pups" to pipeline valves.The welding processes covered are shielded metal arc welding, gas tungsten arc welding, gas metal arc welding, flux-cored arc welding with and without shielding gas, and submerged arc welding. This European Standard is not applicable to flash girth welding, resistance welding, solid-phase welding or other one-shot welding processes, nor to longitudinal welds in pipe or fittings, to "hot-tap" welding of pipelines in service or to the welding of process piping outside of the scope of ISO 13623.NOTEAdditional requirements may be necessary for welding of pipeline for particular pipeline operating conditions. These can include limitations on maximum hardness or strength, minimum impact toughness values, crack tip-opening disNOTEAdditional requirements may be necessary for welding of pipeline for particular pipeline operating conditions. These can include limitations on maximum hardness or strength, minimum impact toughness values, crack tip-opening displacement, all weld metal tensile testing or bend testing, thermal stress relief or others. Where appropriate, these additional requirements should be added to the requirements of this International Standard in a project-specific supplement.