Vanes Repair-Type in No.4 Hydroturbine of the Danjiangkou Hydropower Plant

The transformation for No.4 turbine in the Danjiangkou Hydropower Station also includes modification of fixed guide vane besides turbine.The fixed guide vane should be designed with the minimal loss of water flow through fixed guide vane since it is pillar of ring.The revised model is mainly implemented through grinding the water-in/out edge of fixed guide vane so as to change the streamline of guide vane,and attempt to make the streamline of fixed guide vane and the scroll lines formed by water flow coincided.This article details the vanes repair-type approach,focuses on the key technology used in repair-type as well as the encountered problems and corresponding solutions.