Oil and gas welding joins pipe, pressure vessels, and structural components for hydrocarbon service, requiring specialized procedures, qualified welders, and rigorous quality control to ensure safety and reliability. Welding quality directly impacts equipment integrity in potentially hazardous service.

Welding challenges in oil and gas include diverse materials from carbon steel to exotic alloys, thick-wall components requiring multiple weld passes, sour service requiring controlled chemistry and hardness, high-pressure and high-temperature service demanding weld integrity, and field conditions with weather exposure and limited access.

Procedure requirements for oil and gas welding include qualification per ASME Section IX or API 1104, specific preheat and interpass temperature controls, post-weld heat treatment for stress relief or property restoration, and chemistry controls for sour service. Welder qualification demonstrates proficiency in required positions and processes.

Quality assurance involves procedure and welder qualification, weld parameter monitoring during production, non-destructive examination per code requirements, mechanical testing for critical welds, and documentation providing traceability. Third-party inspection verifies code compliance and quality.