FURNACE DOOR CLOSURE SYSTEM

A guillotine-style door closure system for a furnace comprises a furnace opening with a door frame on a vertical side of the furnace; a furnace door adapted to mate with the frame; a left closing chain mounted, at one end, to the vertical side of the furnace approximate the left jamb and the lintel of the frame, and mounted, at its other end, to a left pin extending from the furnace door approximate the left vertical side of the door, below the vertical centerline of the door and distal from the rear vertical side of the door; and a right closing chain mounted, at one end, to the vertical side of the furnace approximate the right jamb and lintel of the frame, and mounted, at its other end, to a right pin extending from the furnace door approximate the right vertical side, below the vertical centerline and distal from the rear vertical side of the door. The left and right pins extend from furnace door at a predetermined vertical height which depends upon a sum of all vertical mechanical forces being substantially equal to zero when the door is closed, a sum of all horizontal mechanical forces being substantially equal to zero when the door is closed, and a sum of all moments about a predetermined point being substantially equal to zero when the door is closed.