Railroad car truck damping member with open cavity and support rib construction

A friction casting for use in a railroad car truck between a side frame column and a bolster pocket slanted wall, the friction casting including a slanted wall adapted to face and be in contact with the bolster pocket slanted wall, said casting slanted wall, when viewed in vertical cross section, having a curvature providing a generally centrally located zone of contact with the bolster pocket slanted wall,

• said friction casting having a bottom wall formed and adapted to seat upon a supporting spring,
• said friction casting having a generally vertical wall formed and adapted to be in contact with a generally vertical wall of the side frame column, and
• said friction casting slanted wall, vertical wall, and bottom wall defining a generally open interior, a support rib in said casting generally open interior, said support rib being joined to said casting slanted wall at the slanted wall zone of contact and being generally perpendicular to said casting slanted wall, said support rib extending to and being joined with said casting vertical wall whereby said support rib supports said casting slanted wall at the zone of contact and transfers the load from the casting slanted wall zone of contact to the casting vertical wall.