Taking a CPR 1000 nuclear steam turbine HP casing as an example, this paper carried out the numerical study to investigate on the deformation of the casing during shutdown.
Based on ProE software, a 3D model for the HP casing was established at first. Secondly, the heat transfer coefficient of every surface of HP casing of the shutdown was calculated by using convection heat transfer coefficient formula in detail, ignoring radiative heat transfer inside the casing. Then, the finite element method was used to calculate and analyze the shutdown of HP casing’s temperature field. In the calculation process, the third boundary condition was used to apply steam temperature and heat transfer coefficient to each area of the HP casing. Finally, the calculation results of the temperature field were used as the input conditions to calculate the stress and strain of the casing, and the possible reasons for the HP casing’s deformation were obtained.