Patent attributes
An hollow railroad car may be a have a lading containment structure that is a pressure vessel. The car may be a covered hopper car having one or more hopper discharge sections. Each hopper discharge section may include a transition from a substantially rectangular upper inlet to a substantially circular outlet. The transition may include developed plate formed as partial conic sections fitted as valleys between respective pairs of fore-and-aft slope sheets and side slope sheets. The car may have substantially planar internal ring reinforcement assemblies that serve to form a jig and a welding surface for the fore-and-aft slope sheet, a self-jig for the skins of the side wall and roof sheets, and which define buckling nodes for longitudinal compression of the car. The rings form local T-sections in combination with the adjacent wall skins, and do not employ out-of-plane formed sections such as hat sections. The reinforcement may be fabricated from flat sheet or flat bar.