Bar frame
A bar frame is a special design of the locomotive frame and, compared to the sheet metal frame also used in steam locomotive technology, was designed as a framework frame , which was produced by rolling. This provides a clear view of the boiler on the locomotive and good accessibility of the internal engine parts for maintenance. The development of different frame shapes came about because the weight of the locomotives was constantly increasing. The prescribed total weight for the Rainhill locomotive race was 6 t, the Badenia locomotive from 1842 already weighed 16.2 t. On the other hand, locomotives at the time the bar frame was created had a weight of around 80 t. The origin of the construction lay in the locomotive technology of the United States .
Use and manufacturing peculiarities
Bar frames were used exclusively in steam locomotives , on the one hand to improve the rigidity of the frame and on the other hand to improve the accessibility to the internal engine in multi-cylinder locomotives . The first locomotive made in Germany to be equipped with a bar frame was the Bavarian S 2/5 from 1904. Before that, the S 2/5 (Vauclain) from 1900 had a bar frame, but these machines were still made by Baldwin Locomotive Works manufactured. At the time of the end of the state railways , locomotives with bar frames were considered a construction principle due to their ease of maintenance and elegance, so that they were used in the standard locomotives. Bar frames could not be made in every locomotive factory. The predominant manufacturing factories for locomotives with bar frames were Krauss-Maffei , Schwartzkopff and Henschel & Sohn . Their production required special equipment from the workshops. The Esslingen machine works, for example, could not process bar frames, and the largest locomotives of the Royal Württemberg State Railways, such as the Württemberg C and the Württemberg K , were made with a sheet metal frame. The Sächsische Maschinenfabrik mainly produced locomotives with sheet metal frames. The only exceptions here are the 18.0 and 19.0 series , with the former having a bar frame in combination with a sheet metal frame. The bar frame was more expensive to manufacture than a sheet metal frame, and therefore the simpler sheet metal frame was often chosen in the production of locomotives with less importance.
With the construction of the DR class 52 , welding technology was used for the first time in the frame construction of steam locomotives ; this locomotive can be used as a replacement for the construction principle of bar frame to sheet metal frame. When the new locomotives with mostly two-cylinder engines appeared after the Second World War , only the sheet metal frame of these locomotives was made using welded construction. The following table shows the locomotives manufactured for German state railways with a bar frame.
| model series | Year of delivery | Number of built locomotives with bar frames | Thickness of the frame side in mm | Number of cylinders | comment |
|---|---|---|---|---|---|
| 01 | 1925-1938 | 241 | 100 | 2 | - |
| 01.10 | 1939 | 55 | 100 | 3 | - |
| 03 | 1930-1938 | 298 | 90 | 2 | - |
| 03.10 | 1939-1941 | 60 | 90 | 3 | - |
| 05 | 1935, 1937 | 3 | 90 | 3 | - |
| 06 | 1939 | 2 | 100 | 3 | - |
| 13.6-8 | 1902-1903 | 22nd | 50 or 100 | 4th | Combination bar / sheet metal frame |
| 14.0 | 1908ff. | 99 | 95 | 4th | Combination bar / sheet metal frame |
| 14.1 | 1904 | 10 | not specified | 4th | screwed from 2 parts |
| 15.0 | 1906 | 1 | not specified | 4th | screwed from 2 parts |
| 17.0-1 | 1910-1914 | 202 | 100 | 4th | Combination bar / sheet metal frame |
| 17.2 | 1914ff. | 124 | 100 | 3 | Combination bar / sheet metal frame |
| 17.4-5 | 1903-1907 | 39 | 100 | 4th | - |
| 11-17-12 | 1914ff. | 77 | 100 | 4th | Combination sheet metal / bar frame |
| 18.0 | 1917-1918 | 10 | not specified | 3 | Combination sheet metal / bar frame |
| 18.2 | 1907-1913 | 35 | 100 | 4th | - |
| 18,201 | 1939 | 1 | 80 | 3 | Reconstruction in 1960 from 61.002 |
| 18.3 | 1918-1920 | 20th | 100 | 4th | - |
| 18.4-5 | 1908-1931 | 159 | 100 | 4th | - |
| 19.0 | 1918-1923 | 23 | 100 | 4th | - |
| 19.10 | 1941 | 1 | 70 | 8th | Locomotive with single axle drive by steam engines |
| 23.0 | 1941 | 2 | 100 | 2 | - |
| 24.0 | 1928-1940 | 95 | 70 | 2 | - |
| 38.0 | 1905-1908 | 51 | not specified | 4th | - |
| 38.4 | 1921 | 80 | not specified | 4th | - |
| 39.0 | 1922-1927 | 260 | 100 | 3 | - |
| 41 | 1937-1941 | 366 | 100 | 2 | - |
| 42 | 1943-1949 | 1061 | not specified | 2 | - |
| 43 | 1926-1928 | 35 | 100 | 2 | - |
| 44 | 1926-1949 | 1989 | 100 | 3 | - |
| 45 | 1936-1937 | 28 | 100 | 3 | - |
| 50 | 1939-1948 | 3164 | 80 | 2 | - |
| 52 | by 1942 | about 300 | not specified | 2 | Production with frames from remnants |
| 56.1 | 1919-1920 | 85 | 100 | 3 | - |
| 56.7 | 1908-1915 | 70 | 100 | 4th | - |
| 56.8-11 | 1915-1919 | 230 | 100 | 4th | Combination sheet metal / bar frame |
| 56.20-29 | 1919-1928 | 846 | 100 | 2 | - |
| 57.5 | 1911-1924 | 95 | 100 | 4th | - |
| 58.10-21 | 1917-1924 | 1478 | 100 | 3 | - |
| 62 | 1928-1932 | 15th | 100 | 2 | - |
| 64 | 1928-1940 | 520 | 70 | 2 | - |
| 80 | 1927-1929 | 39 | 70 | 2 | - |
| 81 | 1928 | 10 | 70 | 2 | - |
| 84 | 1935-1937 | 12 | 90 | 2 | - |
| 85 | 1932-1933 | 10 | 100 | 3 | - |
| 86 | 1928-1943 | 776 | 70 | 2 | - |
| 87 | 1927-1928 | 16 | 70 | 2 | - |
| 95 | 1922-1924 | 45 | 100 | 2 | - |
| 97.4 | 1920 | 1 | 80 | 4th | Rack locomotive |
| 99.20 | 1917 | 1 | not specified | 4th | Narrow gauge locomotive type Mallet for 1000 mm gauge |
| 99.22 | 1931 | 3 | 60 | 2 | Narrow gauge locomotive for 1000 mm gauge |
| 99.73-76 | 1928-1933 | 32 | 60 | 2 | Narrow gauge locomotive for 750 mm gauge |
Manufacturing peculiarities
A structure of the bar frame is explained here using the frame of the 19.0 series . The bar frame consisted of the two rolled frame cheeks, which (from front to back) with the buffer beam , with the cylinders, the suspension of the Krauss-Helmholtz steering frame, the control carrier, the rear attachment of the control carrier, several cross struts and pendulum plates, the brake cylinder carrier, the frame of the tag axle frame and the coupling box for the tender are stiffened and connected. The individual truss parts could be riveted or screwed. The frame cheeks in this series had a clearance between the frame cheeks of 1,070 mm, they had a maximum height of 700 mm and a length of 13,660 mm.
The two frame cheeks had only become possible in production through experience in armored ship construction. In addition to the axle bearing guides , the frame cheeks had several large, weight-saving windows. For the arrangement of the cylinder group and the driver's cab, it was drawn in to a lower height and reduced in thickness in places.
The frames were designed to be elastic. This made it possible for the locomotive to have sufficient resistance in the event of a poor superstructure and operational features such as buffer shocks. Due to their lower height compared to sheet metal frames, they were more prone to bending, especially when lifting without superstructures. That is why the axle fork stays had to be attached constantly.
Maintenance specifics
Frame cracks were not uncommon with bar frames. For every scheduled inspection that was carried out in the repair shop at intervals of around 1.5 years , the locomotives had to be disengaged and the frame examined. Here, the axle fork stays must be attached to the axle cutout again immediately after they have been axially removed, in order to avoid bending the elastic frame. If cracks appeared, they had to be jointed at an angle on both sides and welded again. A particularly weak part of the frame in the 01 series was the area between the cylinders and the first coupling axle. An accumulation of cracks automatically resulted in the production of an insert. In addition to this work, the axle bearing guides were renewed and the fitting screw holes checked. Unplanned events such as derailment or a rear-end collision resulted in an unscheduled maintenance stage with a general assessment and measurement.
Web links
- Comparison of the different frame types for steam locomotives
- Photo of a bar frame of a quadruple coupled locomotive on www.bahnbilder.de
- Photograph of a bar frame ( DR series 50 ) on www.bahnbilder.de
literature
- Karl-Ernst Maedel , Alfred B. Gottwaldt : Deutsche Dampflokomotiven , Transpress Verlag , Berlin 1994, ISBN 3-344-70912-7 .
- Manfred Weisbrod, Hans Müller, Wolfgang Petznick: Steam locomotive archive, series 01–99 , Transpress-Verlag, Berlin 1976.
- Jürgen-Ullrich Ebel: Saxon Express Locomotives Volume 2 , EK-Verlag, Freiburg 2000, ISBN 3-88255-120-8 .
- Wolfgang Messerschmidt: Lokomotivtechnik im Bild , Motorbuchverlag, Stuttgart 1991, ISBN 3-613-01384-3 .
- Manfred Weisbrod, Wolfgang Petznick: Series 01 , Transpress Verlag, Berlin 1979.
Individual evidence
- ^ Photograph of a rolled bar frame from 1903 on www.drehscheibe-online.de
- ^ Karl-Ernst Maedel, Alfred B. Gottwaldt: Deutsche Dampflokomotiven , Transpress-Verlag, Berlin 1994, ISBN 3-344-70912-7 , p. 32.
- ^ Karl-Ernst Maedel, Alfred B. Gottwaldt: Deutsche Dampflokomotiven , Transpress-Verlag, Berlin 1994, ISBN 3-344-70912-7 , p. 158.
- ^ Manfred Weisbrod, Hans Müller, Wolfgang Petznick: Steam locomotive archive, series 01-99 , Transpress-Verlag Berlin 1976.
- ↑ Jürgen-Ullrich Ebel: Sächsische Schnellzuglokomotiven Volume 2 , EK-Verlag, Freiburg 2000, ISBN 3-88255-120-8 , p. 16.
- ^ Wolfgang Messerschmidt: Lokomotivtechnik im Bild , Motorbuchverlag, Stuttgart 1991, ISBN 3-613-01384-3 , p. 163.
- ↑ Manfred Weisbrod, Wolfgang Petznick: Series 01 , Transpress-Verlag, Berlin 1979, p. 90 ff.
