Dual-mode Unimog at the InnoTrans 2012 in Berlin
Powertrain with torque converter clutch and crawler gear transmission
Eco-friendly and cost-effective operations
At the 9th InnoTrans in Berlin, the leading global trade show for the railway industry (18 through 21 September), Mercedes-Benz will exhibit new implement configurations for the Unimog on rails. The particular interest of the professional circles will be on the Unimog U 400 as a shunting vehicle that is also suitable for clearing snow. The basis is provided by a newly designed powertrain that in addition to a torque converter clutch for pulling heavy loads also includes a crawler gear transmission for very slow operating speeds. This means the Unimog can also be equipped with a snow blower for clearing snow off the tracks or the road. Thanks to a rapid-change mechanism the snow blower can be attached or detached quickly and conveniently, making the dual-mode Unimog available for clearing snow off a railway crossing or a company road even at short notice. The snow blower is powered by the Unimog’s mechanical front power-take-off shaft available ex-factory. The rail technology comes from Zagro and consists, among other things, of a railway car brake system, upward-pivoting buffered couplers and a radio remote control. DB FuhrparkService GmbH will take possession of the Unimog on display at the trade show; it will be operated by DB Regio Nordostbayern in Hof, Germany.
Even more efficient rail cleaning
Another innovation on the Mercedes-Benz InnoTrans exhibition stand is a rail and grooved rail cleaning vehicle for tram operations. The newly developed rail gear from CMAR makes it possible even for the Unimog with a long wheelbase of 3600 mm and consequently larger body volume to navigate very tight turning radiuses of at least 19 metres. For rail cleaning the Unimog vehicle hydraulic system controls five different work processes from lowering and pressing down the rail gear to driving a high-pressure water pump for cleaning grooved rails.
Continuous drive and remote control
Mercedes-Benz will also display the U 400 with rail gear and railway technology from Zagro and the XS 122 loading crane with man basket from HIAB, a vehicle for the multi-faceted jobs in the railway infrastructure, for example, for bridge inspections or repairs to the catenary. The Unimog chassis comes ex-factory with hydrostatic drive that allows continuous adjustment of the operating speed, even by remote control from the man basket.
Eco-friendly and cost-effective shunting
The fact that the Unimog is driven by the road wheels on the rails – on standard-gauge railway tracks as well as on various international wide gauges – predestines it for use as a shunting vehicle. Since the friction coefficient of rubber on steel is significantly higher than that of steel on steel, the dual-mode Unimog can develop enormous pulling power at a comparatively low weight, and can tow loads of up to 1000 tonnes. Generally speaking, the Unimog transfers the high emission standards of road transport onto the rails. With its low fuel consumption during shunting – the experience of many customers shows a fuel consumption of about 5 to 6 litres of diesel fuel per hour of operation – makes the dual-mode Unimog an eco-friendly and cost-effective alternative to a shunting locomotive.
Some 80 to 100 Unimogs with dual-mode design are delivered to railway companies around the world each year, making the legendary universal motorised working machine (the full German name of the Unimog) a fixture in this industry as well.