Figure 3.3. Typical Journal Box Assembly.
lining that is soft but tough and durable. Because a bearing is subject to continuous wear while the car is in
motion, it is designed for easy removal and replacement.
Journal roller bearings have been in use on passenger cars for some time and, in the last few years, the
number of freight cars equipped with roller bearings has more than doubled; in the future, all new freight cars
and more and more old ones going into shops for major repairs will be equipped with some type of roller
bearing. Because the journal roller bearing assembly, with its sealed lubrication unit, can run for 3 years
without requiring any added lubricant, maintenance and inspection time will be greatly reduced and the
traditional hotbox troubles causing schedule delays will be considerably less.
The Army has few freight cars with journal roller bearings: its passenger and ambulance cars,
however, have journal boxes using grease-lubricated roller bearings. Because of the need