WIND BAND - Galvanized sheet steel with two formed reinforcing ribs. Supported by the galvanized steel brackets. It affords protection from weather and cross winds. THROAT - Galvanized steel inner throat is welded to angle ring. EXTERNAL BRACING - Used on larger units to give extra rigidity and prevent sagging and vibration. DAMPER LIDS - Open automatically when fan is turned on, close automatically when fan stops. POSITIVE BUMPER STOPS - Adjustable neoprene tipped bumper stops assure immediate closing when fan is cut off, yet permit maximum air flow when open. DAMPER BEARINGS - Shutter lids turn on sintered bronze-oil bushings mounted on rust-proof rods for lifetime of resistance-free operation. Mounted outside of airstream. NEOPRENE BUMPER - Mounted around top of throat. It assures positive damper contact. Prevents freezing in cold weather. Dampens sound when closing
PROCESS ENVIRONMENTS
