Abstract: The stay ring and spiral casing of hydraulic turbine were analyzed and calculated by using the 3D-FEM analysis, and the stress and displacement calculating result of stay ring and spiral casing under hydraulic pressure test condition were obtained. The calculating result shows that when the yield strength of material is satisfiable, the spiral casing operation will be safety.

Key words: stay ring and spiral casing of hydraulic turbine, finite element method (FEM) analysis, strength and deformation