We accompanied one of the SWIETELSKY track-laying machines to a major service

The SWIETELSKY Bahnbau SMD-80 track-laying machine has already been used in many corners of the continent. We have reported on this several times: without claiming to be exhaustive, we have also covered projects in Hungary, such as the Gödöllő – Hatvan railway development, but also in the Czech Republic, Denmark, and Austria.

We now report on the annual overhaul of the giant machine, which was carried out at the central workshop of the SWIETELSKY Vasúttechnika parent company in Fischamend. We asked Sabolcs Karoly, the SWIETELSKY Vasúttechnika Kft.'s engineering coordinator, about the maintenance work and the machine chain itself.

The SMD-80 is suitable for

• rebuilding existing tracks (i.e. replacing the rail and concrete sub-base),
• separately only for the replacement of the concrete substrate,
• to dismantle the tracks,
• and to lay new track on the previously constructed crushed stone ballast.

The size and weight of the chain is accordingly quite impressive: approximately 200 tonnes, 60 metres long without wagons. It is capable of laying up to 1 800 metres of track in a single shift, but it can also complete longer sections in the event of demolition or laying new track.

At least one month each year is dedicated to the technical inspection of SMD-80

As Szabolcs Károly explained, the annual maintenance process takes 4-6 weeks.

"Before maintenance, it is essential to plan the tasks to be performed, the components to be repaired and to order and manufacture the necessary parts. The extensive facilities at the Austrian site are a great help in this respect", he explained.

As regards the main inspections carried out during the operation, we learned that safety inspections are carried out first and foremost, covering structural elements, railway bicycles and the braking system, among others.

The machine will also be partially dismantled during the weeks of maintenance: of course, only to the extent that the design and excavation tasks identified require.

And what exactly is replaced in the machinery chain is always changing. There are so-called major wear parts that almost always need to be replaced during overhauls, for example:  

• the scraper chain forming the profile of the crushed stone and its wear plates,
• the stone-driving rubber bands,
• and the wheels of the portal cranes.

Of course, this list is not exhaustive, the description of the repairs carried out could be listed over many pages - added Szabolcs Károly.

They have also worked in the Netherlands, Sweden and Croatia in the last two years

We also asked the engineering coordinator about the importance of the SMD-80 in the work of the group. He stressed that the SWIETELSKY Bahnbau AG has the only fast conversion machine of this type and is exploiting its capabilities and advantages, including its versatility, its short machine length among structures capable of performing similar tasks and the fact that it uses technology for conversion that allows it to "push" the concrete subway cars in front of it, thus allowing it to use the so-called ""push" technology. This means that it can be used effectively in "in-between" work areas (so that, in the case of a rebuild starting from a station area, the station head siding can be cleared quickly, thus minimising disruption to rail traffic).

Finally, the engineering coordinator summarised the progress of the machinery chain and the Hungarian team operating it over the past two years. "We've covered quite a lot of ground: last year we had a project of more than 80 kilometres in Sweden, but we also work very often in the Netherlands and Croatia. In addition, the machine has also been deployed on several 'smaller' jobsites in Austria, Germany and Luxembourg, for example."