Patent ID: 7334771

Claim:
A blocking apparatus for blocking or sealing off a line for transporting dust-laden gases, wherein the line has an open area along a length of the line at which the line may be blocked or sealed; the apparatus including a sealing element at the open area of the line; a movable closure body which selectively bears against the sealing element in a blocking or sealing position of the closure body; a rotation device connected to the closure body for rotating the closure body about an axis of rotation, the rotation device extending along the rotation axis; a flexible linkage between the rotation device and the closure body, so constructed that the closure body can move along a direction of the axis of rotation and also can move in a direction which is perpendicular to the axis of rotation, such that the closure body slides on the sealing element whereby the position and location of the closure body may be altered at least along the direction of the axis of rotation; and a spacer which is hydraulically actuated to apply a force to move the closure body at least along the direction of the axis of rotation at least during operation of the blocking apparatus.