摘要 |
An improved seal arrangement is disclosed for use in batch coil annealing furnaces. The furnace has extending from its base a pair of cylindrical upright supports having exposed membrane engaging seal edges and between which an underpressure chamber is formed. The inner cover which removably rests on the base, has an annular top plate extending radially outwardly from its sidewall adjacent the cover's bottom end. Extending vertically downwardly from the top plate are concentric inner and outer clamp mechanisms which clamp flat annular elastomer seal therebetween. An overpressure chamber is formed between the seal and the top plate and when the inner cover is seated on the base, an underpressure chamber is formed between the seal and the upright supports. A positive pressure is applied to the overpressure chamber and a vacuum is drawn in the underpressure chamber to insure that the seal is forced into sealing contact with the upright engaging surfaces, thus assuring a positive seal of the inner cover with the furnace base.
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