The railway infrastructure in Great Britain is characterized by a particularly compact structure gauge. This dictates a narrow cross section for track construction and maintenance machines. Additional installations such as power rails require the tamping unit to be particularly flexible. The 4x4 tamping technique has a long tradition in the United Kingdom. The tamping unit can be rotated and shifted sideways. The tamping tines can be tilted up by 90 degrees. This adaptability means that the complete turnout area can be tamped.

In order to achieve sustainable compaction under every sleeper, Plasser TampingControl ensures that operators receive visual feedback immediately while working. This allows them to simply and easily assess the quality of filling and compaction of the ballast.

Balfour Beatty has now ordered four new Unimat 08-4x4/4S machines that can do even more: the goal is to reduce noise, diesel, and CO₂. The new fleet will therefore be equipped with electric tamping units. A generator for generating power directly at the gearbox ensures optimum efficiency.

As practical experience with retrofitted units (eco-retrofits) has already shown, the electric drives on the tamping unit reduce the engine speed. This results in less noise, lower fuel consumption, and lower CO₂ emissions. It remains to be seen when the Unimat 08-4x4/4S with green tamping units will tamp in parallel for the first time.