Mixing a wide variety of construction materials

Wide range of applications

A particularly impressive feature of the KMA 220 / KMA 220i is its capability to mix many different unbound source materials. The plant can roduce cold mixes from a large variety of new aggregate mixtures, reclaimed recycling materials and binders. Reclaimed asphalt pavement nd other construction materials recovered from existing road pavements are suitable for environmentally friendly recycling and reuse.

Suitable binders include cement, bitumen emulsion or foamed bitumen, which are delivered in special tanker trucks. The precise quantities finders and aggregate to be added are determined by preliminary investigations in a road laboratory. The plant uses them to produce a homogeneous mix with the specified material properties. Foamed bitumen is a highly economical binder as it requires very low application rates.

Foamed bitumen
A binding agent offering lots of potential.


The performance of the specimens manufactured in the road laboratory is verified by means of mix design testing.

The performance of the specimens manufactured in the road laboratory is verified by means of mix design testing.

Innovative technology mixes precisely to formula

A multitude of highly precise, easily accessible measuring and control instruments ensure that the formula is adhered to with pinpoint accuracy. Two gate valves at the outlet of the proportioning hopper permit the source material to pass onto the take-off conveyor where the aterial is weighed by means of the integrated belt scales and then transported to the mixer. Here, water and binders are added precisely in accordance with the weight of the source material. Water is drawn from tanker trucks or from the integrated water tank and is then injected via the flow meter and injection bar. Hydraulic binders such as cement are proportioned via highly sensitive weighing augers, bituminous binders via flow meters.

Water and bitumen emulsion are injected at the inlet of the take-off conveyor into the mixer. An electrically heated injection bar for the addition of foamed bitumen is positioned directly above the material inlet to the mixer.

Market-leading and cutting-edge products for the Road and Mineral Technologies business sectors are constructed at the WIRTGEN brand headquarters in Windhagen, Rhineland-Palatinate. With its innovative, high-performance and cost-efficient products and technologies for cold milling, soil stabilization, hot and cold recycling, concrete paving and surface mining, WIRTGEN leads the world market in road construction and repair, as well as in mining natural rock and pay minerals.