Bolted Joint Simulation Techniques in Gas Turbine Components

Abstract

Bolted joints are integral part of many industrial applications such as the most simple to the most complex and expensive machinery. They provide the primary means of connecting components. These joints play an important role in the integrity and durability of the systems. Bolted joint simulation is one of the important aspects of designing and evaluating any assembly. FE modeling simulation for bolted joint pose limitations in terms of simulating the real life bolted joint behavior. Simulation should be accurate enough but also simple enough to solve model faster. There are many practices exist that helps the analyst to simulate the bolted joint. These practices need to be reviewed in detail and evaluated against high fidelity 3D finite element model. The physical behavior of the bolted joint can be simulated accurately by 3D bolted joint with preload, friction and contact between mating parts. The detail 3D modeling of bolted joint for the complex assembly models with multiple bolted joints will be very expensive in terms of computational cost and time. This study presents multiple methods of bolted joints simulation using ANSYS® 12.1[1]. The bolted joint model simulated using beam element is very effective in terms of computational cost, time and memory usage for complex assembly models. Bolted joint simulation with threads happens to be the most rigorous with the results and this method is a yardstick. Other approaches are evaluated from points of view of accuracy and effort effectiveness. This paper also presents the bolted joint analysis best practices on using above methods for various stages of component design. Typical gas turbine flange is taken for case study.