Modena – removing large surface courses with minor obstacles
Despite the extensive public transport system, more than 120,000 vehicles use the inner-city roads in Modena every day. This leads to considerable wear on the roughly 850 km of roadway criss-crossing the city in the Emilia-Romagna region of northern Italy. The Department of Public Works and Maintenance constantly invests in their maintenance in order to contain the damage to the roads.
For instance, in the eastern part of the city, where 4 cm of the surface course had to be removed over a total stretch of roughly 2 km, all within the framework of routine work near the fruit and vegetable wholesale market.
High traffic volumes and particularly the immense number of heavy goods vehicles made it essential to complete the project as rapidly as possible. At the same time, maximum precision was required during the milling work, as supply lines located in some parts of the road meant that numerous manhole covers had to be circumvented. Normally, this would have called for classic team work, with a large milling machine first removing most of the surface course before a small milling machine takes over and finishes off along the edges and around the manhole covers. Not so in this case. Instead, Endi Asfalti decided to make use of just one cold milling machine, the W 200 Hi. The new concept with the hydraulically driven milling drum assembly also proved effective in Modena, for this assembly permits considerably smaller milling radii. As a result, the machine operator first used the W 200 Hi to cut accurately round the manhole covers lining the edge of the road on the right and left-hand sides before the larger surfaces were removed in a single pass by the large milling machine with its powerful 433 kW and a speed of around 20 m/min. In this way, the maintenance job was completed quickly and reliably, as demanded.
Prato – Medieval town centre with narrow streets and alleys
The situation in the medieval town centre of Prato was completely different. Located 10 km northwest of Florence, the main town of the eponymous province is a famous production and trading center for fashionable textiles. As in Modena, the authorities in Prato are anxious to maintain the high standard of their network of roads with the aid of an efficient repair and maintenance program. In the characteristically narrow winding streets, different milling depths had to be strictly adhered to in order to avoid damaging the historical stone slabs under the asphalt pavement. The roads' narrow width of just 4 to 5 m was another challenge: Although essentially a job for a small milling machine, the Wirtgen W 200 Hi once again proved victorious with its numerous features.
Roughly 300 m of asphalt pavement had to be removed along the Via Carbonaia, one of the roads inside the town's original walls. A milling depth between 5 and 12 cm was needed to reprofile the superstructure for the surface and binder course and at the same time prevent damage to the subgrade. Aided by the automatic LEVEL PRO leveling system, the machine operator was easily able to comply with the different milling depths specified. The automatic LEVEL PRO leveling system is integrated into the machine control system and constantly compares the current milling depth with the required depth which is rapidly preset via a useful memory function. This yields precise, high quality milled results and intuitive, simple operation.
In view of the road's narrow width, however, turning was impossible. This was no problem for the W 200 Hi: With the hydraulically driven milling drum assembly which can also be displaced sideways, the milling machine was able to work right up to the edge on both the right and left-hand sides, as required. A major advantage on site, this feature is also decisive when working on motorways in particular, both when working parallel to concrete safety barriers in the direction of travel and with regard to logistics. It allows trucks to veer off into the site quickly and safely and subsequently re-enter the stream of traffic in the direction of travel.
Scaffolding projecting into the road was a further hindrance in downtown Prato – but one which was elegantly (and safely) bypassed by the large Wirtgen milling machine with its movable milling drum assembly. While the machine chassis and operator's platform ensured a safe distance between the operator and scaffolding, the two zero edges allowed the milling drum assembly to continue cutting through the asphalt pavement right up to the edge of the road.
Tailored to the operator's needs
According to Roberto Rinaldi, one of the main advantages of the W 200 Hi is that it has been specifically tailored to the needs of the machine operator. The experienced Endi Asfalti operator works with the W 200 Hi almost every day and is impressed by the machine: "The milling machine is at its best when working on long stretches outside the town districts and ensures maximum productivity. Most of our jobs are located in downtown areas, however, and that is where the W 200 Hi demonstrates its edge over other models." For Rinaldi, the combination of movable milling drum, a perfect overview to both sides and such useful features as the display and other operating systems are highly advantageous when it comes to precision and productivity. "I reckon the time saved by using the Wirtgen W 200 Hi is around 30%." And the small milling machine normally required for the finishing work is not needed, either.
"If you include easy operation with the multifunctional joystick or LEVEL PRO, then the Wirtgen W 200 Hi represents the next level for me – particularly when working in downtown areas," says Rinaldi full of enthusiasm for this groundbreaking development by Wirtgen.