JPS6085262A - Draining method of residual water in tailrace of water turbine - Google Patents

Abstract

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.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for draining residual water in a water turbine discharge channel by using an existing exhaust pipe in a runner room and an existing drainage pump in a drainage pin.

A method for draining residual water in a conventional water turbine spillway will be explained based on drawings. The drawing is a cross-sectional view of a general water turbine or pump turbine. Drain the remaining water in chamber 4 and draft pipe l. Beyond the draft gate 2, the spillway 5 leading to the lower dam continues uphill for approximately 1 km.
It is separated from the lower dam by a spillway gate 6 installed at the water outlet.・If it becomes necessary to inspect the spillway 5 for some reason, the remaining water in the spillway 5 must be drained using the water extraction pump 2 mentioned above. The water level is within 50 m to 1θ0 m below the water level at the gate 6, and it takes several days to drain all the remaining water in the spillway 5, resulting in enormous manpower costs.

In order to eliminate the above-mentioned problems, the present invention provides a method for draining residual water from a water turbine spillway, which is characterized by collecting water in a water pit and discharging it to the ground using a drainage pump of the drainage pin. be.

In other words, the remaining water in the water turbine's tailrace, which was conventionally drained only by the υ1 water pump in the draft pipe, is guided to the drainage pit by using the existing exhaust pipe in the runner room, and is then drained to the ground using the existing drainage pump in the drainage pit. Since this method is used in conjunction with the method of draining water into the drain, the time required for draining the water is greatly shortened, resulting in an effect of reducing costs.

The present invention will be specifically explained based on the drawings. In the figure, the υ1 trachea 7 that exhausts the runner chamber 4 when the pump-turbine completes its phase adjustment operation opens into the upper cover 8 of the runner chamber 4, and is connected to a drainage pit 9 located deep underground. ing. The drainage pit 9 is mainly used to collect all waste water such as cooling water from power generation, electric machines and water turbines, underground spring water, etc. and discharge it to the ground, and is equipped with a large drainage pump 1O.

The method of draining the remaining water in the spillway 5 of the water turbine according to the present invention is to divert the above-mentioned exhaust pipe 7 to guide the remaining water in the spillway 5 to the drainage pit 9, and use the large drainage pump lO of the drainage pit 9. When carrying out water drainage, it is necessary to adjust the opening degree of the valve 11 of the exhaust pipe 7 to prevent water from overflowing into the water pit 9, and the valve 11 that applies negative pressure is usually It would be more practical to replace the sluice valve or globe valve with a funnel valve. As a result, compared to the conventional drainage method using only the drainage pump 3 of the draft pipe 1, drainage can be performed in about half the time and cost can be reduced.

[BRIEF DESCRIPTION OF THE DRAWINGS] The drawing is a cross-sectional view of a typical water turbine or pump water turbine. 4...Runner room, 5...Discharge channel, 7...Exhaust pipe,
8...Top cover, 9...Drainage pit, 10...
drainage pump.

Claims (1)

[Claims] A feature of this feature is that water remaining in the discharge channel of the water wheel is collected in the drainage pit by diverting the exhaust pipe that opens in the upper cover of the water wheel and leads to the drainage pit, and drains water to the ground using the drainage pump of the drainage pit. A method for draining residual water from water turbine tailraces.