GAF: Pushing for modernisation in maintenance and repair

In spring 2018 the first of 28 latest generation Track Working Vehicles (GAF) was handed over to DB Netz AG. The newly developed vehicles are considerably more powerful and flexible than the old GAFs with trailer, which are being gradually replaced throughout Germany.



Transports, installations and more – the new generation of GAFs at DB Netz AG is a big push towards modernisation. In 2016 the Deutsche Bahn AG infrastructure operator ordered 28 new generation GAFs from Plasser & Theurer. Just two years later they were put into operation. The GAFs are part of the family of the Track Infrastructure Multifunctional Maintenance Vehicles (MISS), a series of measuring and work vehicles, so far supplied exclusively to DB Netz AG to add to its diverse machine fleet. 

Major step into the future 

The engineers’ attachment to their new GAF could be seen when the first vehicle was baptised on 2 May 2018 in Oberhausen to mark the start of trial operations and staff training: Carsten von der Höh, Track District Manager at DB Netz AG and as part of a team of 10 involved in the development of the machine, called the first new GAF 746 001 “Bumblebee”. “The vehicle marks a milestone, a major step into the future,” said Philipp Glanz, Track Area Manager for Duisburg Production Services at DB Netz. 

This major step into the future affects all aspects around the subject of the Track Working Vehicle. DB Netz deploys its GAFs nationwide for maintenance and repair work. Among its core activities are the replacement of sleepers or closure rails following a rail break, or the replacement of whole switch frog points and switch blades. The large loading area, also suitable for bulky and heavy components, the powerful crane and the new facility to carry four rail pieces of up to 20 m length on the side of the frame on retractable consoles are features which are highly appreciated in day-to-day work. 

Multifunctional for various tasks 

The new DB series 746.0 as a joint new development can do much more than all its predecessors. The latter used to be units made up of track vehicles of varying power and trailers. This has been a proven concept, but it is possible to do even better. Lifting and transporting rails and other loads is only one possible task. The new crane with integrated control and driver’s cab 1 can be converted with low effort to perform other functions. If time is of the essence, it takes less than 2 minutes from switching on the crane to its first movement. Depending on its task, the remote-controlled crane can be equipped with a workman basket or a wood grab. It can also be used directly for vegetation care with a pruning saw, an embankment cutter or a mulcher. Digging work is not a problem either – various grabs and excavator buckets can be fitted for excavation work. No supports are required when using the crane – this makes work much easier and faster. The same applies to the central storage of small parts and lifting tackle in a box under the loading area, well protected and accessible directly from above. 

The second end of the vehicle wagons (exact length over buffers = 23 m) houses the fixed installations with driver’s cab, crew compartment and toilet. The table is big enough for six people. A separate air conditioning unit provides the temperature control for the whole cab. This is a must as work is underway at any time of the day, if required, and of course in any weather conditions. The GAFs are also designed for attaching snow clearing equipment. In the winter of 2017/18 a similar GAF of the new, dual-engine DB series 747.0 proved itself on the Karwendelbahn railway in the Alps with its additional winter equipment, i.e. plough blade, rotating brush and a snow blower that can be attached to the crane. Depending on requirement, material wagons or even a rail loading unit can be coupled to the GAF. Coupled wagons when braked may weigh up to 50 t, technically a maximum of 480 t is possible. Furthermore, all GAFs can be connected in tandem drive. Tests have shown that the GAF has the capability of hauling a complete ICE train.

Underfloor drive in frame 

The GAF engine with the fans is housed underfloor in the main frame. The water-cooled eight-cylinder Deutz diesel engine with an output of 480 kW, the exhaust gas routing with SCR catalytic converter and particulate filter as well as the silencer form one compact unit. The hydrodynamic drives on three of the four axles are from Voith and are standardised on all MISS machines. The fuel capacity allows for up to 1000 km of travel or 49 hours of working. 

Outlook

Of the 28 new DB series 746.0 GAFs that have been ordered the first six will be put into service in 2018, a further 13 in 2019 and another nine by autumn 2020. They are part of the Berlin machine fleet and can be found in DB Netz regional depots throughout Germany.