Simulation of a welding process for a structural repair of a gas pipeline, from a simplified two-dimensional finite element model

Analysis of the influence of physical variables of steel

Abstract

The pipes and components installed in process plants, refineries, compressors and those derived from petroleum, are designed in accordance with ANSI / ASME B31.8 [1] and constructed, using appropriate and qualified procedures by addition of welding material. For this implementation rules structures and pressure vessels, American Welding Society [2] and American Society Mechanical Engineering ASME IX [3], allows to design all kinds of joints and qualify welders. Since a failure is detected in an operation pipeline, the ability to conducting a "Weld in Service", the repair procedure requires careful planning, considering that the pipe is under pressure and with fluid. The repair procedure presented in this paper, involves the placement of a structural reinforcement around the damaged section, with a material having similar characteristics and thus allowing structurally recover of the damaged sector. Based on previous studies, conducted by "Advanced Analysis Techniques", through the Finite Element Method, a simulation of the welding process was carried out. On this occasion, from a simplified two-dimensional finite element model, considering the influence of the temperature dependent of the physical properties with respect to temperature, such as thermal conductivity and specific heat, is studied in the final results.