Abstract: In the field of semiconductor integrated circuits, vertical furnaces are critical equipment used for thermal processing, featuring a vertical structural layout. If the O-ring of the swinging furnace door fits too tightly or too loosely against the reaction chamber, it can adversely affect the lifespan of components and reduce the equipment's reliability. This paper focuses on the design and research of a cost-effective, automatically sealing swinging furnace door. The study concludes that a sealing swinging furnace door combining an O-ring with a spring and driven by a cylinder can meet the requirements for reliable sealing. Additionally, the selection of a buffer to absorb kinetic energy can mitigate the impact of door vibrations on the equipment.