1. Field of the Invention
The invention pertains to fire resistant firesleeve assemblies as used with hose or pipe systems, and particularly pertains to the sealing of the cut end of a firesleeve utilizing fibrous heat insulative components.
2. Description of the Related Art
Hose systems, particularly fuel, lubricating and hydraulic hose used within aircraft engine compartments, often require fire resistant protection to minimize the likelihood of fire or high temperatures damaging the flexible elastomeric hose of the hydraulic circuits. Typically, resistance to fire and high temperature is achieved by encompassing the hose and portions of the associated hose fittings with a protective firesleeve. The firesleeve often consists of a silicone rubber tube surrounding the hose and/or fitting and the firesleeve usually includes an inner insulative material such as asbestos or glass fiber to provide insulation against the transfer of heat.
Typically, firesleeve material is shipped and stored in indeterminate lengths, often wound upon reels, and the firesleeve is cut to the desired length to accommodate the length of hose with which it is to be used. As the cutting of the firesleeve to the desired length will expose the end of the firesleeve and the fibrous material thereof it is required that the end of the firesleeve be treated or sealed so as to discourage contamination of the firesleeve inner fibrous material and prevent the "wicking" of moisture, fluids, or other liquids into the fibrous material by capillary action.
To "seal" the cut ends of firesleeves, the conventional practice is to dip the cut firesleeve end into a silicone formulated "end-dip" liquid sealant so as to saturate the braided fibrous material adjacent the firesleeve end. Thereupon, the silicon end dip composition is dried and processed prior to the firesleeve being installed upon the associated hose. Such processing of the ends of firesleeves often requires a 24 hour delay, and the handling of a dipped firesleeve is messy, produces dripping, and such end dipping is hazardous and may not produce a liquid impervious end seal.
Further, the silicone formulated end dip used to seal firesleeves may be classified as a hazardous material requiring special and expensive transportation procedures. Further, end dipped firesleeves do not produce a significant frictional engagement with the hose or hose fitting unless the clamping pressures are unusually high and there is a tendency for the firesleeve to axially slide on the hose, possibly exposing a portion of the hose adjacent the fitting to fire in high temperatures.
3. Objects of the Invention
It is an object of the invention to provide a fluid impervious end seal for hose or pipe firesleeve assemblies which is inexpensive, requires no dipping or application of fluids, requires no hazardous materials, and eliminates assembly and processing delays.
Another object of the invention is to provide a seal for the cut ends of hose or pipe firesleeves wherein the seal is formed by a flexible resilient liquid impervious cuff enclosing the firesleeve cut end which totally confines the cut end to produce an effective liquid seal, enhances fire protection, and produces an attractive aesthetically finished hose assembly.