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Optimal mounting.

Bidirectional Unimog U500 with eight-spindle screw machine (ASM) 30.75.
Bidirectional Unimog U400 with eight-spindle screw machine (ASM) 30.75.

Both of these precision screw machines at PORR allow perfect results when loosening and tightening the rail mounting. The 8-spindle precision screw unit with a bidirectional unimog as a carrier vehicle enables fully automatic, synchronous loosening and tightening of rail fastenings.

Both the quality (through computer-supported recording of the torques achieved) and the performance is above-average compared with conventional screws.

Technical data.

  Typ Unimog U400 Typ Unimog U500
Manufacturer (carrier vehicle) Mercedes U400, bidirectional device Mercedes U500, bidirectional device
8-spindle precision screw unit  Robel Bahnbaumaschinen GmbH Robel Bahnbaumaschinen GmbH
Additional device, loading crane HIAB-Kran XS 144E-3 Palfinger PK 9501
Motor capacity 175kW/Mercedes Benz 170 kW/Daimler Benz
Total mass, max. 18t 21t
Driving speed (street), max. 90km/h 80km/h
Driving speed (track), max. 20km/h 50km/h
Length over buffers 8,100mm 6,800mm
Number of axles 3 2

Performance parameters.

  Typ Unimog U400 Typ Unimog U500
Work performance, screws up to 600m/h up to 600m/h
Min. working radius ≥ 60m ≥ 40m
Min. driving radius ≥ 60m ≥ 40m
Towing capacity, max. 400t -
Train control system     No No
Safety gear change      Yes No
Perfectly positioned.
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Modern treatment.
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Laying tracks
The best-laid tracks.
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Conveying – storing – unloading
Completely mechanised.
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Cable-free measuring.
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Vegetation control
Flexible control.
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