Automated FEA for Risk Based Hot/Half Bolting of Flanged Joints

Abstract Hot bolting is a critical maintenance procedure performed on pressurized flanged joints, commonly seen in industrial environments such as refineries and chemical processing facilities. As a result, the analysis of hot bolting is frequently required in downstream operations. This paper describes an automated Finite Element Analysis (FEA) framework for assessing the structural integrity of flanged joints during hot bolting and half bolting operations. The methodology facilitates the rapid construction of a wide range of models through its user interface, accompanied by 3D visualization of the results. Additionally, it supports risk-based assessments of both full and partial bolting configurations, allowing for a detailed evaluation of reduced bolting patterns and their impact on joint integrity. The automation method and resultant tool accurately represents the geometry and material properties of crucial joint components, such as flanges, bolts, gaskets, and associated piping, using industry-standard geometry and material libraries. A detailed nonlinear FEA-based analysis to examine the nonlinear behavior of gaskets and the contact interactions between individual components under variable thermal load, pressure conditions along with piping load during hot bolting operations was employed. This paper details the development of automation algorithms, validation through benchmark analyses, and its application in case studies reflecting real-world scenarios. The results emphasize the tool’s capacity to provide accurate risk assessments, offering an optimized approach to enhancing safety, reducing downtime, and supporting more comprehensive roll-out of hot and half-bolting in plant maintenance and shutdown operations.