Austauschbauart

The so-called Austauschbauart wagons were German railway vehicles produced from the late 1920s onwards which had common components built to agreed standards.

The German term Austauschbau ('interchangeable component manufacture') is a manufacturing concept. The idea was initially used in the field of mechanical engineering, but is now the basis for industrial mass production techniques.

The basis of Austauschbau manufacture is that:

Any quantity of part 'A' produced at different times and in different places, must match any quantity of a similarly produced part 'B' without further finishing being required.

In short, it is a system of common, mandatory, standard production tolerances and fits that are specified for components, based on their function. To comply with the standards, special machines and tools are used that also meet precise tolerances. In addition, measurement tools and training are needed, to ensure compliance with the guidelines, both during manufacture and as part of quality control afterwards. Part of the principle is to design in as many standard parts as possible - screws, bolts, etc. - right from the concept stage. Austauschbau has enabled the division of labour and specialisation in modern industry, leading to economic mass production of complex machines, tools and vehicles.

From about 1921, by order of the Reich Transport Ministry (RVM), almost all goods wagons were marked with the name of their owner, "Deutsche Reichsbahn", the name of a so-called "class district" (Gattungsbezirk), a wagon number ( Wagennummer) and category letters (Gattungszeichen). The wagon bodies were painted in red-brown livery (paint number 11a), the wagon roofs in light grey (paint number 47) and the chassis, railings, etc., in a black colour (paint numbers 14,24,33).

In 1927 the DR switched over to standard colours (Einheitsfarben) based on the RAL colour system 840-B. From 1940, the livery colours were changed again, for example, from December 1941 the iron roofs of covered wagons were painted grey-black (RA 7021) and no longer in green-grey, and, from 1942, most of the wagons only bore the letters "DR", the name of the class district, a wagon number and a category letter.

From 1921 all goods wagons with the same or similar functions were grouped into so-called class districts which were the names of German cities, mostly those in which there was a Reichsbahn divisional HQ. From 1926, the DRG introduced the following additional class districts:

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