Standard Especificación del Procedimiento de Soldadura (SWPS)
A Norma Procedimiento de soldadura Especificación (SWPS) is an AWS B2.1-series document that manufacturers and contractors can adopt in lieu of developing a custom WPS. Under D1.1:2025 Clause 6.2.1.2, SWPSs may be accepted for use with Engineer approval, covering specific processes, base metals, and joint configurations without independent Ensayo de calificación.
What Is an SWPS?
An SWPS is a Welding Procedure Specification developed and published by AWS based on qualification test data accepted during the B2.1 document development process. Rather than requiring every Fabricante to independently qualify a procedure, an SWPS provides a document covering specific processes, base metals, joint configurations, and parameter ranges backed by existing PQR data. Under D1.1:2025 Clause 6.2.1.2, acceptability of an SWPS is the Engineer's responsibility to exercise based on the specific structure or service conditions.
SWPSs are published in the AWS B2.1 series. Each document specifies essential variables, parameter ranges, Metal Base restrictions, and the Precalentamiento and Temperatura entre Pasadas Requisitos for the covered process and joint configuration.
SWPS vs Custom WPS vs Precalificado WPS
A custom prequalified WPS (Clause 5) is developed by the fabricator and meets all D1.1 Clause 5 requirements without Ensayo — the fabricator writes and owns the document. A custom qualified WPS (Clause 6, Part B) requires a PQR with physical coupon testing. An SWPS is a third path under Clause 6.2.1.2: the fabricator adopts an AWS B2.1 document with existing qualification test data as an alternative to independently qualifying a WPS, subject to Engineer approval and the SWPS's stated parameter envelope.
Adoption requires a written document identifying the specific SWPS number and edition, confirming that production variables fall within the SWPS's Variable esencial ranges, and indicating the organization's Aceptación of responsibility for the procedure. The adopting organization operates within the parameter Límites of the published SWPS — deviating outside those limits requires independent WPS qualification.
Limitations of SWPSs
SWPSs cover a defined set of base metals, thicknesses, and joint configurations. High-Resistencia steels, exotic alloys, or non-standard joint geometries may fall outside the published SWPS range — in those cases, a custom qualified WPS with PQR testing is required. Each B2.1 document references the D1.1 edition under which it was developed; Verificar that your contract-specified D1.1 edition accepts the specific B2.1 SWPS document before adoption.
Essential Variables and the SWPS Envelope
Every AWS B2.1 SWPS defines an envelope of essential variables — the specific ranges of welding parameters within which the procedure is valid. These include the Proceso de Soldadura, base metal specifications and groups, Metal de Aporte classifications, Gas de protección composition, preheat and interpass temperature ranges, Diámetro del electrodo, current and Voltaje ranges, and Velocidad de Avance limits. The adopting organization must verify that every production variable falls within this published envelope before welding begins.
Under D1.1:2025 Clause 6, a change in any essential variable beyond the limits stated in the SWPS constitutes a deviation that requires independent qualification. For example, if an SWPS covers GMAW on Group I and II base metals with 75/25 Ar/CO2 shielding, switching to 100% CO2 shielding falls outside the SWPS envelope and requires a separate qualified WPS with PQR testing. Similarly, welding a base metal Espesor greater than the Máximo listed in the B2.1 document cannot be covered by the SWPS — the fabricator must qualify the procedure independently under Clause 6, Part B.
Preheat compliance is a common oversight during SWPS adoption. The SWPS specifies Mínimo preheat values based on the base metals and thicknesses it covers, but these may differ from Tabla 5.11 values for the same materials when used in a EPS precalificada. The adopting fabricator must follow the preheat requirements stated in the specific B2.1 document — not assume that Table 5.11 values apply automatically. Use the preheat calculator to verify Table 5.11 minimums for Comparación against SWPS-stated values.
More WPS Resources
Frequently Asked Questions
An SWPS is an AWS B2.1-series document that provides a pre-qualified welding procedure backed by existing PQR test data. Under D1.1:2025 Clause 6.2.1.2, fabricators can adopt an SWPS instead of independently qualifying a custom WPS, subject to Engineer approval.
A prequalified WPS (Clause 5) is written by the fabricator and meets code requirements without testing. A qualified WPS (Clause 6, Part B) requires PQR coupon testing. An SWPS is a third path under Clause 6.2.1.2 where the fabricator adopts an AWS B2.1 document with existing qualification data, subject to Engineer approval and the SWPS parameter envelope.
Adoption requires a written document identifying the specific SWPS number and edition, confirming that production variables fall within the SWPS essential variable ranges, and indicating the organization accepts responsibility for the procedure. Deviating outside the published parameter limits requires independent WPS qualification.
SWPSs cover a defined set of base metals, thicknesses, and joint configurations. High-strength steels, exotic alloys, or non-standard joint geometries may fall outside the published SWPS range and require a custom qualified WPS with PQR testing. Each B2.1 document references a specific D1.1 edition — verify your contract-specified edition accepts the SWPS before adoption.