A machine optimized for Sweden's infrastructure. Strictly speaking, it's two machines in one. The Unimat 09-2X-4x4/4S can lift, line, level, and tamp plain-line track and turnouts to maintain the optimized position. Two Infrakraft teams work with this machine alternately from March to mid-December at the latest, as Machine Fleet Manager Michael Belsing reports. The deployment time depends on the weather and region.
Machine Fleet Manager Michael Belsing from Infrakraft
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Average shift output
Versatile tamping technology
The 2X-4x4 tamping unit is at the heart of the machine. With two different tamping unit segments, it is very versatile: the Unimat works as a powerful continuous 2-sleeper tamping machine on plain-line track and in large parts of the turnout. If there are obstacles or the sleeper spacing becomes irregular, 1-sleeper mode is a safe option. There are also many adjustment mechanisms on board for working in the turnout: the tamping unit can be rotated, extended laterally, and is equipped with tilting tines. A 3rd-rail lifting unit lifts the turnout construction evenly across the width, which protects the cost-intensive components of the infrastructure, especially in the case of continuous long bearers and heavy concrete sleepers.
This versatility also means that all parts of a turnout, including the diverging rail, can be treated. The integrated sweeping unit leaves a clean finish by removing excess ballast. Infrakraft works on behalf of Trafikverket, Sweden's transport authority. The impressive Unimat 09-2X-4x4/4S, painted black, is used on newly ballasted track and for track maintenance. Sections of around 1,000 metres per shift are usually treated.
In the summer of 2025, we accompanied the team working in Uddevalla, where the railway station is being completely modernized. The Infrakraft team describes individual experiences from the field.
Punctuality and safety go hand in hand
Trains must run precisely according to schedule and arrive on time. Railway route maintenance plays a decisive role in this. It is usually performed at night, even if operating staff prefer to work during the day, as visibility conditions and their ability to handle strain are better.
It's a dangerous job we have out there.
Machine Supervisor Peter Brodin
This is my first machine with modern camera systems. The more you can see, especially when it starts to get dark, the safer you feel. This makes travel much safer, especially when working.
Operator Christoffer Gamnis
Spare and wear parts on board
On average, 180 to 200 shifts are worked per year. Maintenance work on the machine has a major influence on its availability. The machine crew is in charge of routine servicing, such as changing filters or replacing wear parts. Spare and wear parts are carried in the spacious cab area. A service provider performs larger servicing jobs in a maintenance workshop.
The need for versatile maintenance of plain-line track and turnouts with universal tamping technology is increasing. In Sweden, transport volumes for transporting people and goods by rail are increasing. Infrakraft is already investing in the successor model, a UnimatExpress 2X-4x4 Dynamic. In addition to the versatile 2X-4x4 tamping unit and sweeping unit, it will also feature the Dynamic Track Stabilizer.
Project data
| Infrastructure manager | Trafikverket |
| Machine type | Unimat 09-2X-4x4/4S |
| Machine operating company | Infrakraft |
| Annual output | 180 to 200 shifts |
| Area of application | |
| Working mode |
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