This conveyor belt design has three door panels in one. The door panel is located between the conveyor belts. The panel rotates parallel within the frame when closed, and 90 degrees perpendicular with the frame when open. When the panel is rotated in the closed position, it has two wedging panels that expand at the top and bottom. The wedging panels seal against the bottom of the carrying belt and the top of the return belt. The rotating panel is attached to the frame by two keyed shafts that the panel rotates on.

When open, the door panel rotates parallel to the deck and is between the two conveyor belts. This prevents the belts from any contact with the panel, which would cause belt wear. The door is rotated by hydraulic cylinders. The cylinders are connected to a rotating door lever at one end and the front face of the frame on the other end. When the rotating panel is closed to the vertical position, the carrying belt will now be flat instead of dished. This procedure does not take up belt slack between bulkheads that require excessive hydraulic pressure increasing with every bulkhead door being closed.

When the door is in the vertical position the expansion wedge plates can be extended. These are used to form a watertight seal on the belt surfaces. These expansion plates are located both at the top and bottom of the rotating panel. The expansion plates are guided and held in place with adjustable wedge plates. Attached to each expansion plate are hydraulic cylinders. When they are energized the rods extend forcing the two expansion wedge plates to extend. When this procedure is complete, the belt plugs are extended to the sides of the conveyor belts. This process completes the watertight integrity of the bulkhead opening.