Hugon chose a Liebherr LTC 1045-3.1 compact crane for a job deep inside the city walls of the medieval town of Carcassonne in France.
To reach the job site the crane driver (the grutier) had to carefully manoeuvre through narrow gates, fortress walls, tight bends and long, narrow streets. Three marshals accompanied the crane, which is owned by crane service provider Hugon, to make sure no damage was made to the historical structures.
“Carcassonne is actually a UNESCO World Heritage Site. Making a mistake like touching the walls was simply unthinkable”, Christophe Vergès, a member of the technical staff at Hugon, explained.
To help navigate through the obstacles of the historical town, precautions, such as removing the storage box on the front, were carried out to reduce the length of the vehicle by more than 1,200 millimetres. The flashing light on the ballast block was also removed and the telescopic boom was lowered. The exterior mirrors were moved in.
One of the greatest challenges along the route from the outer city walls to the job site included a 25 metre long passage through the outer ring of the fort, the Porte Narbonnaise. The passage consists of four gates, one of which is offset at an angle of around 45 degrees.
To overcome these obstacles the crane’s various steering modes were used, including crab, all-wheel and independent rear axle steering for a small turning circle. To pass through the smallest and lowest gate into the citadel, which had a clearance height of 3 m, the driver’s cab was telescoped forwards into the lower road position. The driver also retracted the cylinders on the hydro-pneumatic suspension by 100 mm.
For this part of the journey it took the crane approximately 30 minutes to travel 400 metres. At the job site the lift was two distributor boxes weighing around 1 tonne each onto a flat roof. The crane was also used to remove the old distributor boxes.
For the return journey, the crane had to once again navigate the narrow streets, however, this time tourists, sun awnings, boxes of vegetables and souvenirs on the cobblestones presented added challenges. After a long day, the crane returned to the Hugon yard in Narbonne early that evening.
Author; Laura Hatton