RSS Fetcher Posted December 22, 2013 Share Posted December 22, 2013 Morning all! To further reduce the backlog of blog entries I have yet to write up, I should like to use this morning for introducing a locomotive which in some way certainly falls in the "oddball" category of German motive power design. That is the case because the loco in question was specifically designed for the sole coherent 25 kV, 50 Hz AC network on German territory – namely, the Rübeland Railway in what today is the state of Saxony-Anhalt. I would think that connoisseurs of the German railway scene will be familiar with this line, but to make sure everyone reading this blog has access to background information, let me just point you to the English and German Wikipedia articles about the line – which with its modest length of just 13 miles and unique route profile and operational pattern I have in recent months found to be a good choice for a first-time layout, whenever I might be able to build one! https://en.wikipedia.org/wiki/Rübeland_Railway https://de.wikipedia.org/wiki/Rübelandbahn However, let's now have a look at a H0 scale model of what has long been the signature locomotive type for the Rübeland Railway – the class 171 electrics, previously known as Deutsche Reichsbahn class 251. As also stated in the Wikipedia articles, the Rübeland Railway is a unique part of the German railway system in that it is an isolated 25 kV, 50 Hz AC line. At Blankenburg, the line is connected to the Halberstadt-Blankenburg Railway, which was never electrified. Consequently, setting up a dedicated 15 kV, 16 ? Hz feeder station solely for the Rübeland Railway was not considered worthwhile when the line was brought up for Deutsche Reichsbahn's electrification efforts in the 1950s. Instead, Deutsche Reichsbahn had the line electrified with 25 kV, 50 Hz so as to be able to divert power from the national power grid. As the line’s steep gradients called for locomotives geared for high tractive effort rather than speed, obtaining a specially designed locomotive class configured for 25 kV only was determined as being the most suitable solution to handle the freight workings serving the Rübeland quarry and the limestone works at Hornberg, Rübeland, Kaltes Tal and Elbingerode. An interesting detail worth writing down here but is that when the class 243 electric locomotive was designed in the 1970s, Deutsche Reichsbahn did, for a while, consider obtaining a dual voltage variant which would have been able to work both on the regular 15 kV network as well as on the Rübeland Railway. Eventually, fifteen Co’Co’ configured electric locomotives, designated class E 251 originally and just 251 from 1970 onwards, were built by the People-Owned Enterprise, Locomotive and Electrical Engineering Works „Hans Beimler“ at Hennigsdorf, and all delivered in 1965. As connoisseurs of the German railway scene will know, this factory, possibly better known by the common shorthand LEW, evolved from a locomotive factory originally set up by AEG, and nationalised in 1948. LEW were, in fact, the only builder of electric locomotives in the German Democratic Republic. The 251 was re-designated class 171 in 1992 following German unification, and continued to be the signature class of the Rübeland Railway until December 2004. The 251s, or 171s, worked both passenger and freight services on the Rübeland Railway, but needed to be withdrawn from passenger services in the year 2000 as they were not outfitted for the zero-speed door blocking circuit – called „TB0“ in the German railway vocabulary – which the Federal Railway Administration had made mandatory as the minimum safety level for revenue passenger services by that time. Eleven of the fifteen 171s were kept in service for working freight services until 2004. In the spring of 2005, Havelländische Eisenbahn were contracted to initially work two thirds, and eventually all, of the freight services on the Rübeland Railway. Three 171s have been preserved, with 171 001 and 002 having been returned to their original appearance and running numbers, E 251 001 and 002. 171 012 was purchased by the Thüringer Eisenbahn-Verein association, and while not able to theoretically run under its own power on any lines other than the Rübeland Railway has since been presented on various railway festivals. Technical description The 251’s design is closely related to that of the class E 11 and E 42 Bo’Bo’ electrics, which had been the first GDR-designed electric locomotives, with the E 11 (redesignated 211 in 1970, and 109 in 1992) having been geared for passenger work, and the E 42 (redesignated 242 in 1970 and again 142 in 1992) for freight traffic. The locomotive’s body is a self-supporting, welded steel assembly set atop a sturdy running frame welded from hollow profiles with cross bracings spaced between the bufferbeams. Below either bufferbeam, a fixed, slotted skirt is installed, which also is intended to double as a snow plough and behind which the main air reservoirs are located. The body proper consists of the two cabs and the large engine room section, where the body flanks carry four pairs of vertically slotted ventilation grilles per side. There also is one rectangular window per side, set between the second and third pair of grilles. The cabs are accessible by way of two doors each, located above the outer wheelset of either bogie. In addition to the door windows, additional side windows are provided in the large corner pillars. Two square windscreens are provided per cab, with a horizontal grab rail set below the windscreens, one shorter horizontal grab rail set immediately above either windscreen, and the air horns attached to the centre pillar between the windscreens, pointing downward. The rooftop carries a pair of RBS 54 diamond pantographs, with the circuit breaker being set near the roof’s centre, slightly offset to the Cab 2 end, and a rooftop fairing being slightly offset towards Cab 1. Rooftop walkways are provided along either body side, while the pantographs, busbar and associated equipment are set atop ceramic insulators which are taller than those on 15 kV locos in order to provide the required safe distance. The bogie frames are welded steel assemblies as well, with the wheelsets being spaced asymmetrically, placing the centre and inner wheelsets closer together for improved curve running properties. All wheelsets are suspended such as to be able to displace laterally, using springs for centring. The body is set atop one pair of helical springs per bogie, supported in suspension pots on the bogie frames. The axle boxes are fixed to multilayered leaf springs, which in turn are connected to suspension levers attached to the bogie frame. As an additional layer of suspension, two rubber dampers are provided for each axle box. The bogies are connected by way of a steering lever mechanism to further improve the loco’s curve running abilities. In addition, Bogie 2 is suspended such that it can displace laterally by several inches. The 251’s electrical equipment comprises the oil-cooled main transformer with attached high tension tap changer, providing 34 power notches. On the output side, the transformer is coupled to a pair of silicon-based rectifiers, providing pulsating current for the universal current traction motors. Its braking gear comprises an indirect, single-lapped pneumatic Knorr brake with settings G and P and direct shunting brake control valve. Furthermore, the 251 is equipped with a rheostatic brake, so that with all braking systems combined, it fulfils the Steep Gradient Regulations ("Steilstreckenvorschrift") which apply to the Rübeland Railway with its maximum gradient of 6.1%. Among other items, the Steilstreckenvorschrift, which applies to all lines with gradients exceeding 4% specifies additional rules for braking force calculation and brake check procedures. The 251/171 was never outfitted with any train protection system as the German Steilstreckenvorschrift specifies that on all trains, two crewmen need to be present on the locomotive. When it entered service in the 1960s, it was but outfitted with a mechanical alerter, which was removed after several years. The model we will be looking at now did come as a surprise to many German modellers, given the 171's limited operational area and small number. It is produced by Rivarossi, and currently offered in three variants: HR2478 – E 251 009 in Epoch III Deutsche Reichsbahn green, black and red and with mechanical alerter HR2451 – 171 005 in Epoch V Deutsche Bahn oriental red without alerter HR2479 – 171 013 in Epoch V Deutsche Bahn traffic red with DB Cargo broadside lettering and without alerter As the scenario I would have in mind for a H0 scale rendition of the Rübeland Railway would involve an operation of tourist trains powered by preserved class 171 locos, I chose the oriental red variant, assuming that this fictional passenger operation would be aimed at representing the various phases of class 171 service on the Rübeland Railway. Of course, I would yet require at least one additional locomotive for a credible working pattern, so unless Rivarossi might yet follow up with a Deutsche Reichsbahn burgundy variant with light grey bogies and ivory trim, I might pick the green variant eventually! In my opinion, the 171 is the best Hornby/Rivarossi model I have put my hands on thus far. As mentioned further up, the 171 is closely related to the Deutsche Reichsbahn class 211 and 242 electrics, and as such, the model provides a convincing representation of the loco's no-nonsense, chunky appearance. All mouldings as well as the model's paintwork and lettering are crisp and clean. Out of the box, the model represents 171 005 after the revision it had been given on 26 March 1997, though of course I would need to have a set of custom wet transfers furnished as the loco would need a full new revision for the fictional passenger operation which I have in mind. When looking at the technical inscriptions here on the Cab 1 end, note the two sets of braking weight indications. The left column specifies the braking weights valid outside of route sections governed by the Steilstreckenvorschrift, while the right column indicates the braking weights which must be calculated with for sections steeper than 4%. As you can see, the regular braking weights are P 159 tonnes G 127 tonnes while the Steep Gradient braking weights are P 120 tonnes G 99 tonnes As it is, the 171 therefore has a braking ratio of 128% or 102% on regular lines, and of 96% or 79% on steep lines. One item I particularly like about this model are the nicely detailed bogies. The cab faces feature the large lower headlights which were typical of GDR-built electric motive power... ...while the rooftop equipment is dominated by the two diamond pantographs. And finally, I found the following videos which feature class 171 locomotives as they could be encountered in both passenger and freight service, about fifteen years ago: Thank you for your time and have a nice Sunday! 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