Study on the Load-bearing Capacity of X80 Submerged Arc Welded Joints Based on Finite Element Model

As the petroleum industry continues to expand rapidly, X80 pipeline steel has become a key material in oil and gas transportation due to its strength and durability. However, welding joints, a critical part of these pipelines, sometimes lack sufficient load-bearing capacity, leading to structural failures. Ensuring the mechanical integrity of these joints is essential for the safe and efficient operation of pipelines. This study employs ABAQUS finite element analysis to assess the performance of welded joints created using submerged arc welding (SAW) and gas metal arc welding (GMAW). By developing 3D models, the study simulates tensile testing, revealing that as displacement increases, the tensile force rises, causing plastic deformation. Necking occurs near the heat-affected zone in the base metal, eventually leading to fracture.Furthermore, internal pressure simulations show that as pressure builds, the highest stress concentration appears on the inner wall of the welded joints, emphasizing the importance of weld strength in high-pressure environments. By visually demonstrating the mechanical behavior of different welding techniques, this study provides valuable insights for improving welding processes in X80 pipeline steel. The findings serve as a theoretical foundation for optimizing pipeline construction and ensuring long-term structural safety in real-world applications.