Railroad car truck damper wedge fittings

A damper wedge for a railroad car truck, said damper wedge being formed to co-operate with a corresponding bolster pocket, wherein said damper wedge comprises:

• a friction member that, in use, is configured so as to movably engage a wear surface of a side frame column of the railroad car truck, said friction member having a non-metallic wear surface;
• a spring seat that, in use, engages a spring of the railroad car truck, said spring seat having an axial centerline;
• and an inclined damper wedge surface, said inclined damper wedge surface having a primary damper wedge angle, and a secondary damper wedge angle;
• said inclined damper wedge surface having a compound curvature;
• said inclined damper wedge surface being a machined surface;
• in operation, said curvature of said inclined damper wedge surface engaging the bolster pocket in rolling point contact;
• said curvature of said inclined damper wedge surface having a working point that engages the bolster pocket when the railroad car truck is at rest;
• said damper wedge having a datum plane that is normal to said non-metallic wear surface and that contains said axial centerline of said spring seat, said axial centerline meeting said inclined damper wedge surface at an intersection point;
• and
• said working point is located on said inclined damper wedge surface downslope relative to said intersection point;
• and said working point is located at a center of a contact patch, said contact patch having a radius of less than 1.5 inches.