Abstract: A span bolster, for carrying a heavy load of a railroad car body and distributing the load to two four wheel two axle railroad bogies or trucks, is fabricated from steel plate and has top and bottom cover plates, top and bottom reinforcement doubler plates, longitudinal spaced apart webs separating the cover plates, body bolsters at each end and a central truck bolster, all formed of metal plate joined together by welding with all critical welds being full penetration welds, and with the span bolster being stress relieved after fabrication.

Abstract: A railway flatcar for carrying a highway trailer, the flatcar having been converted from a conventional railway box car. The sides, ends and roof of a conventional box car are cut and removed therefrom substantially at the floor line. The side sill assemblies of the car are reinforced substantially throughout their length. At the bogie end of the car, those portions of the out-board floor stringers spanning between adjacent cross ties and cross bearers are reinforced. The cross ties are also reinforced and/or additional cross ties added at the bogie end of the car. At the hitch end of the car, appropriate reinforcement and mounting means are located along the bolster and center sill to which a conventional trailer hitch is affixed.