Pipe orifice gasbag blocking structure of hydropower station drain pipe

The utility model relates to a pipe orifice gasbag blocking structure of a hydropower station drain pipe. The pipe orifice gasbag blocking structure of the hydropower station drain pipe comprises a gasbag installed on the pipe orifice part of the drain pipe, the gasbag is connected with a gas source through a gas pipe, the drain pipe is installed in a concrete wall body, the outer wall of the drain pipe is fixedly connected to a support ring, a screw rod is slidingly installed on the support ring in the radial direction of the drain pipe, one end of the screw rod is connected with a helical casing in a spiral mode, the helical casing is connected to a motor shaft of a motor, the motor is installed in the concrete wall body through a support, the other end of the screw rod is hinged to a blocking plate through a connecting rod structure, one side face of the blocking plate is fixedly connected with the gasbag, and the gas pipe is arranged on one side face of the blocking plate; a water outlet of the drain pipe is connected with a water outlet pipe sleeve in a spiral mode, the inner wall of the water outlet pipe sleeve is provided with a seal annular groove, and the seal annular groove makes contact with the gasbag face after the gasbag is filled with gas. The pipe orifice gasbag blocking structure of the hydropower station drain pipe has the advantages that the structure is simple, the design is reasonable and delicate, underwater blocking is not needed in operation, and the operation is safe and reliable; the gasbag and the blocking ring are used for conducting double blocking, and therefore the blocking effect is good.