Quickly mountable and demountable sealing device for hazardous chemical tank truck

The invention discloses a quickly mountable and demountable sealing device for hazardous chemical tank truck. The sealing device comprises an annular shell, an annular groove and a seal strip. A plurality of axially-distributed extrusion components are arranged between the seal strip and the bottom of the annular groove, and the extrusion components inwardly press the seal strip to realize automatic compensation of the seal strip. The annular shell comprises a first semicircular seal part and a second semicircular seal part, and the first semicircular seal part and the second semicircular sealpart are connected detachably. Two ends of the first semicircular seal part are provided with a positioning hinge pin and a first positioning hole, and two ends of the second semicircular seal part are provided with a positioning sleeve and a second positioning hole. Each extrusion component comprises an arc positioning plate and a driving air cylinder in the annular groove, and each driving aircylinder is fixedly connec