Pipeline pressurizing expansion plugging device

The invention relates to the technical field of pipeline plugging, in particular to a pipeline pressurizing expansion plugging device, and aims to solve the problems that the plugging reliability is insufficient, the plugging success rate is difficult to guarantee, and the plugging time is short. The device comprises a conveying assembly and an expansion assembly. The lower end of the conveying assembly is connected with the expansion assembly. The conveying assembly comprises a hollow main shaft; the lower end of the hollow spindle is connected with the expansion component; the hollow main shaft moves along the axis of the hollow main shaft; the expansion assembly comprises an expansion bag; and the expansion bag is communicated with the hollow main shaft and is configured to expand to block the pipeline after being internally pressurized. The pressure in the expansion bag is adjustable in an expansion mode of filling high-pressure liquid, so that the pressure in the expansion bag is adjusted according to th