Turbine Flow Parts Surfacing Deformation Analysis

Because the hydraulic turbine unsteady blades in HuangHe抯 upper Reaches water power station have been deteriorated by mud and sand, and destroyed by cavitation erosion for many years, their original designed form has been changed. When the electrode collar bead welding was used to repair of the hydraulic turbine blade, some degree winding can be found after the blade was welded, especially, vertical flexibility (~O.5nim) can抰 meet the needs of the water course perfonnance for the hydraulic turbine blade turning around. In this paper, the vertical deformation value was tested after several blades were welded. When the graphic analytic solution was applied to calculate the welding deformation, Lt a /c i (i~?s-welding coefficient, a -heat expansion coefficient)was assumed a fixed value. However, because the blade is a large and thick workpiece, t.~ , a /c p is not a fixed value. ~-?~ a Ic p was not only revised by numerical solution ,but analyzed by three dimensional finite element analysis of the ABAQUS software in this paper. The result shows that the deformation error of revised model is inside the scope of requirement(veitical flexibility error<5%).So it provides reference and theory basis for us to control welding deformation. Morefore,it is necessary to predict the welding deformation and determine the optimal sequence of welding by the computer in the course of the known parameters of welding ,performance of material and geometry of the blades. In this paper three dimensional finite element of the ABAQUS software is successfully applied to predict the maximal value and the curve of longitudinal flexibility , the distributing plot of stress and the optimal sequence of welding.