roller bearing

One of the two types of rolling, or antifriction, bearings, the other being the ball bearing. Like a ball bearing, a roller bearing has two grooved tracks, but the balls are replaced by rollers. The rollers may be cylinders or shortened cones. If the rollers are cylindrical, only radial loads (perpendicular to the axis of rotation) can be carried, but with conical rollers both radial and thrust, or axial, loads (parallel to the axis of rotation) can be carried. In a given space, a roller bearing can carry a greater radial load than a ball bearing can.

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The Timken Roller Bearing Company was one of the first to introduce roller bearings for railroad cars. Railroad cars owned and operated by the Atchison, Topeka and Santa Fe Railway (ATSF) were some of the first to use roller bearings rather than "oil waste journal" boxes.

Also, the ATSF was the first company to have roller bearing trucks made by Timken under their passenger cars, much to the delight of their passengers, and the bottom line for the company. Timken commissioned the construction of a demonstration boxcar in 1943 that was first seen at the 1948 Chicago Rail Fair. It was a rolling advertisement for a new way of reducing friction - roller bearings (made by the Timken Roller Bearing Company). The car's trucks lacked the then common axle journal boxes, with the bearings mounted on the axles between the wheels.

The first locomotive to use roller bearings made by Timken was Timken 1111, a 4-8-4 built by ALCO in 1930. The locomotive was used on 15 American railroads for demonstration runs, and was purchased by Northern Pacific Railroad (NP), the last railroad to try the specially-built locomotive, in 1933. It operated in regular service on NP until it was retired in 1957 and then scrapped.