In order to meet the continually growing transport requirements in the emerging Federal Republic, the Deutsche Bundesbahn was also eager to replace the many different types of pre-war cars as quickly as possible. Open freight cars for transporting coal were required in large numbers, for example. For this reason, the DB together with the Uerdingen wagon factory developed a two-axle open car with 5.40 m wheelbase up to 1952. A total of 14,919 of the Omm52 were built up to 1962 and delivered to the Bundesbahn. The cars had a frame of welded hollow box sections with welded on head pieces. The running gear was already designed according to UIC directives with a suspension with double suspension rings. Initially the cars were delivered with a Hildebrandt-Knorr freight train brake, later series then with the more modern Knorr standard brake. One part of the car had a handbrake, with the brakeman's platform being screwed onto one side of the sole bar and the cars therefore had an asymmetric running gear with different overhangs. The first deliveries of vehicles with a handbrake still had a metal brakeman's cab. However, some of the cars were already delivered from the factory only as a piped vehicle and did not have a brake system. The body of the cars was also welded and had side doors and movable drop ends at the front which allowed unloading via dumpers. On the other hand, cars with a handbrake had a fixed front wall on the handbrake side. Almost all Omm52 cars were included in the EUROP fleet and therefore freely available to the member railways.
