While-drilling water plugging device for emergency rescue drilling

The invention provides a while-drilling water plugging device for emergency rescue drilling, relates to the field of drilling, and solves the problems that drilling needs to be switched and the drilling operation efficiency is low when a water outlet stratum is drilled. The device comprises a bypass assembly, a pneumatic spray head and a drill rod with an inner cavity, wherein at least the upper portion of the drill rod is a double-wall drill rod with an inner pipe and an outer pipe, and a containing cavity used for storing a plugging agent is formed between the inner pipe and the outer pipe; the pneumatic spray head is provided with a liquid inlet and an air inlet which communicate with each other, and the liquid inlet can communicate with the containing cavity; the bypass assembly is provided with a main flow channel and a bypass flow channel, the main flow channel communicates with the inner cavity, and the bypass flow channel is blocked from the air inlet; and when the main flow channel is blocked, the by