Cold milling machines have a decisive impact on the quality of road rehabilitation

Wirtgen's customer-oriented development expertise is a guarantee of innovations tailored to the needs of the market. The new solutions for cold milling developed at the brand headquarters in Windhagen are founded on practical know-how and core competences in leveling, control and cutting technology.

Cold milling is one of the first measures taken when a roadway or traffic area needs to be rehabilitated. The fast and efficient removal of asphalt and concrete surfaces through cold milling produces an even base which is true to line and level and ideal for paving surface courses in a uniform thickness. The condition of the milled surface has a key impact on the quality of the new surface course to be paved, on its service qualities and on the efficient and economical execution of the rest of the construction work.

Cold milling also has a lasting effect on the construction process when complete pavement structures are removed. Equipped with state-of-the-art milling and leveling technology, Wirtgen milling machines can remove either the complete pavement or the individual surface, binder or base course. When pavements are milled in layers, the milled material can be separated and selectively recovered according to mix type. This lays the ground for targeted reuse of the RAP.

One of the decisive factors in the creation of a milled surface true to line and level is precise leveling. The purpose of leveling is to regulate the milling depth or slope automatically and as precisely as possible based on a reference line. In the field, it has become standard practice to copy an existing surface.

But teamed with a wide range of sensors and applying the latest methods, the Wirtgen LEVEL PRO/LEVEL PRO PLUS leveling system can do much more than simple copying. In the multiplex system, for instance, three sensors on each side of the machine scan the height. The automatic leveling system factors all three measurements into its analysis so that the preset target milling depth is met exactly, but any unevenness in the road surface is not copied. This is a highly effective way of leveling out longitudinal undulations. What is more, defined surface profiles can be created, such as specified cross slopes on race tracks or crowns. This allows the entire road structure to be rehabilitated if necessary.

LEVEL PRO PLUS leveling system: Also for the small milling machine W 50 Ri

On small milling machines, height adjustments used to be carried out manually by lowering the lifting columns of the rear crawler units. In its latest generation of small milling machines, Wirtgen has further optimized the leveling process, offering LEVEL PRO PLUS as an option for the W 50 Ri, too – and fully integrating the system in the machine control system. Having fewer interfaces means shorter signal paths in the control systems and faster reactions between them – factors which all add up to an efficient and precise leveling process. The high degree of automation in the system also makes life easier for the machine operator.

The progressive automation of technical processes likewise plays a key role in optimizing the milling result. With this in mind, Wirtgen put the focus firmly on process optimization along with ease of operation when advancing its small and compact milling machines.

Multifunctional armrest: Perfect control of every job with the W 50 Ri

The highlight of the operating concept is the ergonomic, individually adjustable multifunctional armrest. With this feature on board, drivers of the W 50 Ri small milling machine can now also adjust the machine height, store and automatically activate different milling depths, switch between camera views or control the cold milling machine with the fingertip steering function instead of the steering wheel. Relevant data are also presented in color on the operating display.

The powerful “heart” of the cold milling machine – the milling drum assembly with all the cutting technology components – also has a critical bearing on the quality, costs and performance of the milling process. Here too, as technology leader Wirtgen is continually developing cost-efficient solutions. A variety of milling drums – for fine milling, for creating rough surface structures, or the ECO cutter for a particularly high area performance, to name but a few – support many different milling applications in asphalt rehabilitation.

In addition, specially configured cold milling machines can also be used in concrete or rock milling. Other customized machine modifications allow steep incline milling on slopes of up to 35° when working on reservoirs, canals and equalizing basins. Cold milling machines are also frequently used to dig trenches for pipelaying or, when fitted with a deep milling unit and narrow cutting wheel, to mill slots. In short, the range of applications is huge.

High machine utilization with the FCS cuts operating costs – Also for the W 50 Ri

To increase the utilization of milling machines and make them more economical to operate, the milling drum in many models can be easily swapped for a differently configured milling drum thanks to the Flexible Cutter System (FCS). As a result, the milling width and/or tool spacing can be varied as required. The W 50 Ri, for instance, can be swiftly modified to carry out a new task, so that it operates extremely cost-efficiently under changing conditions.