摘要 |
A rigid, molded fiberglass duct having an integral bendable elbow comprised of two sections of cured fiberglass securely bonded to a corrugated metal-foil sleeve. The method of manufacturing the rigid bendable duct is by sliding a corrugated metal-foil sleeve on to a mandrel and then wrapping the ends of the sleeve with uncured fiberglass. The area of the uncured fiberglass overlapping the corrugated, bendable sleeve is compacted by means of a collar which fits around the sleeve and the fiberglass and compresses the fiberglass into the corrugations of the sleeve. In order to enhance the bond, protusions may be provided in the overlapping area of the sleeve, such as by cutting the corrugated sleeve and bending it up to form tabs.
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