Patent 5988074 Issued on November 23, 1999. Estimated Expiration Date: December 23, 2017. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
A composite roof having a core encapsulated in multiple layers of fiber reinforced plastic is provided. The composite roof may be mounted on a conventional railway car during initial manufacture or used to replace a damaged steel roof on a conventional railway car. The layers of fiber reinforced plastic provide non-corrosive and non-leaking exterior and interior surfaces for the composite roof. The core may be formed from various materials which provide improved resistance to heat transfer between the interior and the exterior of an associated railway car. The composite roof may be mounted on an enclosed structure having a pair of end walls, a pair of side walls and a floor. An opening may be formed in each side wall to allow access to the interior of the railway car. A top retainer and guide rail assembly will typically be mounted above each opening to allow installing a door to control access through the respective opening. A strip of fiber reinforced plastic is preferably attached to the top retainer and guide rail assembly to form a composite rain gutter over each opening.
"Scrimp Systems" brochure of Composite Resin Infusion Molding, p. 2 diagram
Trinity Industries Inc. "Shipper's Problems . . . Trinity's Solutions" pamphlet of steel box car features