Girth Welding on Oil and Gas Pipeline Projects in China

摘要

This paper introduces development of girth welding of long-distance oil and gas transmission pipelines in China, focusing on automatic welding equipment researches and application. Based on characteristics of high strength line pipes, the paper points out a few technical difficulties in girth welding, including the wide range of line pipes, various composition of alloy, refinement of grain and increase of carbon equivalent. It also describes the girth welding processing and grooving of China's high strength line pipes, indicating that the reliability, adaptability and stability of CPP automatic welding system in China's pipeline construction have been highly recognized. This paper argues that self-shielded flux cored arc welding (FCAW-S) and low hydrogen electrode manual welding (SMAW) will still be choices for oil and gas pipeline construction, while automatic welding will be the major method in the future.