Water retaining and draining device for hydropower station deep hole steel lining runner maintenance

The invention relates to the technical field of water retaining devices, in particular to a water retaining and draining device for hydropower station deep hole steel lining flow passage overhaul, which comprises a left water retaining plate and a right water retaining plate, a middle water retaining plate is arranged between the left water retaining plate and the right water retaining plate, a positioning mechanism is arranged on one side of the middle water retaining plate, and a guide mechanism is arranged on one side of the left water retaining plate and one side of the right water retaining plate. The positioning mechanism comprises a positioning piece, one end of the positioning piece is provided with an insertion piece, the positioning piece is provided with an offset piece, the guiding mechanism comprises a guiding piece, the guiding piece is provided with a locking piece, an expansion piece is arranged in the guiding piece, and a fixing piece is arranged in the expansion piece. In addition, the devia