Standby lubrication water supply device for water lubrication bearing draining pump

A standby lubrication water supply device for a water lubrication bearing draining pump comprises a water supply main pipe. The water supply main pipe is provided with a main water supply valve and communicated with a water storage tank through a standby lubrication water pipe and an isolation ball valve, an external water supply floating ball switch is arranged at the position of an outlet of the water storage tank, an overflow pipe is arranged at the highest water level of the water storage tank, an emptying ball valve is arranged at the lowest level and connected with the overflow pipe, and a water outlet pipe of the water storage tank is connected with a lubrication water pipe of a water pump motor group through a water outlet ball valve, a pressure reducing valve, the isolation ball valve and a lubrication water supply valve. A branch pipe is arranged on a water pump water outlet pipe to be communicated with the water storage tank through a damper, a reverse water supply ball valve and a reverse water su