API St 1104-2021 (2023) PDF

Full title and description

API Standard 1104 — Welding of Pipelines and Related Facilities. This listing corresponds to the 22nd edition (published July 2021) and includes Errata 1 issued in September 2023; it is distributed in electronic (PDF) and printed formats and is commonly referenced for qualification, fabrication, inspection and acceptance of welded pipeline systems.

Abstract

Specifies requirements for the welding of butt, fillet and socket welds in carbon and low-alloy steel piping used for transmission and related pipeline facilities. Covers qualification of welding procedures and welders, welding processes, fabrication and repair procedures, nondestructive and destructive examination, and acceptance criteria for new construction and in-service work. Errata published in September 2023 corrects and clarifies selected normative references, figures and test-sample requirements.

General information

• Status: Active (current edition with published errata).
• Publication date: July 2021 (22nd edition); Errata 1 issued September 2023.
• Publisher: American Petroleum Institute (API).
• ICS / categories: 25.160.01 (Welding, brazing and soldering — welding in general).
• Edition / version: 22nd edition (2021) — includes Errata 1 (2023).
• Number of pages: 174 pages (typical published PDF/print length).

Scope

Applies to welding of metallic pipelines (primarily carbon and low-alloy steels) used for the transport of crude oil, petroleum products, fuel gases and other related media. The standard addresses both shop and field welding, new construction and in-service welding and repair, and defines qualification procedures for welding procedures and personnel, inspection and testing requirements (destructive and nondestructive), and acceptance criteria for welded joints. Errata and subsequent clarifications refine normative references and selected test/specimen requirements.

Key topics and requirements

• Welding processes allowed (SMAW, GMAW, GTAW, SAW, FCAW, flux/plasma, oxyfuel and others when applicable).
• Procedure qualification requirements (PQR/WPS) including mechanical testing and test coupons.
• Welder qualification, essential variables and requalification rules.
• Acceptance criteria for destructive tests (tensile, bend, nick-break) and nondestructive testing (RT, UT, MT, PT) and required defect limits.
• Requirements for in-service welding and emergency repairs, including limitations and supplementary inspection.
• Documentation, records, and traceability: WPS, PQR, welder performance records and inspection reports.
• Special provisions and illustrative figures clarified by Errata 1 (September 2023) for normative references and selected figures/tables.

Typical use and users

Used by pipeline operators, engineering firms, welding contractors, certified welding inspectors, quality managers, welding procedure developers, regulatory bodies and training organizations. Typical applications include new pipeline construction, tie-ins, maintenance welding and third‑party inspection and certification for transmission and distribution piping systems.

Related standards

Commonly referenced with other industry and welding standards such as API SPEC 5L (line pipe specifications), ASME/ANSI piping codes and pressure‑equipment standards, AWS welding specifications and national pipeline safety regulations. Users typically consult API 1104 alongside material, pipe specification and inspection standards when preparing procedures and project QA/QC plans.

Keywords

Pipeline welding, API 1104, welder qualification, procedure qualification, nondestructive testing, welding inspection, butt weld, fillet weld, in‑service welding, acceptance criteria, PQR, WPS, pipeline fabrication.

FAQ

Q: What is this standard?

A: API Standard 1104 is the industry standard that establishes requirements for welding of pipelines and related facilities, covering qualification, inspection and acceptance of welded joints.

Q: What does it cover?

A: It covers welding processes, procedure and welder qualification, destructive and nondestructive examination methods, acceptance criteria, repair welding and documentation for carbon and low-alloy steel pipelines in both shop and field environments.

Q: Who typically uses it?

A: Pipeline operators, engineers, welding contractors, CWIs/SCWIs, QA/QC personnel, regulators and training organizations involved in pipeline fabrication, installation, maintenance and inspection.

Q: Is it current or superseded?

A: The current published edition is the 22nd edition (July 2021) and it includes Errata 1 issued September 2023; this edition is active and widely used in industry.

Q: Is it part of a series?

A: API 1104 is part of API's portfolio of standards for pipelines, materials and inspection; it is commonly used together with related API specifications (for example API SPEC 5L for line pipe) and national/regulatory piping codes.

Q: What are the key keywords?

A: Pipeline welding, welder qualification, procedure qualification, nondestructive testing, acceptance criteria, WPS, PQR, repair welding, API 1104.