[China Aluminum Industry Network] how to calculate aluminum alloy shutter doors and their small activities? The amount of aluminum alloy shutter doors is calculated based on the actual width of the shutter door (the height of the door opening + 60 cm) by the actual volume of the roller shutter door. The rolling shutter door is used for the calculation of fans, and the area occupied by the small and medium-sized doors in the original roller shutter door should be deducted (the “93†comprehensive budget quota is incorrect).