This patent application belongs to the gas equipment field, relates to a gas sweeps a shutoff cover, and including the adjusting lever, support cover, inflation cover, the adjusting lever runs through and supports the cover, the adjusting lever with support cover threaded connection, the part cover that supports the cover is worn out to the adjusting lever having the inflation cover, the adjustment rod cover has the one end of inflation cover to be equipped with fastener, the inflation cover is along radially being divided into expand layer, voltage resistance, frictional layer, inflation in situ portion is equipped with inclosed well idle loop, and the frictional layer can be dismantled with voltage resistance and be connected, fastener is anti retreat nut, and anti retreat nut can dismantle with the adjusting lever and be connected. This gas sweeps a shutoff cover, the quick shutoff of being convenient for to stand wear and tear, high pressure resistant, the change of being convenient for increase substantially operating mass with rated load.