New empirical design practice to evaluate the sealing capability of split flange for steam turbine

In the oil and gas industry, machines and equipments usually operate in harsh and tough service conditions due to the exposure at high temperatures and pressures, as well as mechanical loads. In this context, operators' safety in operating machines shall be granted, notwithstanding the adoption of new design criteria due to cost reduction and new operative conditions. While Finite Element Analyses allow the simulation of working stresses and deflections accurately, these results need to be compared with experimental data in order to identify conditions which correspond to leakages in turbine horizontal split flanges. This paper proposes a new design criterion that permits to verify the sealing capability of metallic butt joints undergoing high temperatures and pressures using the results of Finite Element Analysis. This criterion is based on experimental data, collected through the simulation of extreme service conditions at which sealing failures occur.