Door of Oulun Shipbuilding Co., Ltd. adopts multiple sliding doors. The door is 16 meters wide and 14 meters high. The door body adopts Baotong's patented white corrugated board, and adopts a wire rope linkage structure. The active fan drives the driven fan through a pulley set to run and stop at different speeds at the same time, ensuring that multiple door fans open or close at the same time. There is no collision between the door leaves, which not only protects the door body, but also has a very good visual effect.