| 摘要 |
PURPOSE:To enable a time for draining water to be decreased to half, by diverting the water into an air release pipe, opened to the head cover of a hydraulic turbine and inducted to a drainage pit, and collecting the residual water in a tailrace into the drainage pit to be discharged above the ground by drainage pumps. CONSTITUTION:A hydraulic turbine or a reversible pump-turbine, when its condenser operation is finished, causes an air release pipe 7 in a runner chamber 4 to be opened to a head cover 8 and inducted to a drainage pit 9 deeply provided under the ground, and the pit 9 provides large drainage pumps 10. The residual water in a tailrace 5 is drained by diverting the residual water into the air release pipe 7 to be introduced to the drainage pit 9 and discharged by using also the large drainage pumps 10. The residual water, when it is actually discharged, is drained while regulating the opening of a valve 11 in the air release pipe 7 so that the water may not overflow the drainage pit 9. In this way, the water can be drained in a time almost half as compared with that by the draining method using only conventional drainage pumps 3 in a draft tube 1. |
