Valve closing device and pipeline system

The invention relates to the technical field of pipelines, and particularly discloses a valve closing device and a pipeline system. The valve closing device comprises a shell arranged on a pipeline ina sleeving mode, a first baffle plate hinged to a liquid inlet, and a push rod movably arranged on the shell, wherein a first gear is rotationally connected to the end, away from the liquid inlet, ofthe push rod, and the other end of the push rod is connected with the first baffle plate; the valve closing device further comprises an impeller arranged between the liquid inlet and a liquid outlet,and a reduction gear set connected with the impeller, wherein a second gear is arranged at the end, close to the first gear, of the reduction gear set; the valve closing device further comprises a second baffle plate hinged to the liquid outlet, wherein a locking rod is arranged at the end, away from the liquid outlet, of the second baffle plate; the valve closing device further comprises a firstconnecting rod hinged to th