As infrastructure development increasingly is tied to reducing greenhouse gas emissions, products like Wirtgen’s new KMA 240i Cold Mixing Plant and its WR series cold recyclers could gain in demand.
The company is launching the world premiere of the KMA 240i mixing plant, which it says delivers “climate-friendly and cost-effective recycling of construction materials.” It is also announcing some technological updates to its WR series of cold recyclers.
The KMA 240i mixing plant can be stationed near the construction site where materials such as asphalt millings or crushed demolition debris can be delivered to it. The plant then mixes the material with water binding agents like foamed bitumen, bitumen emulsion, or cement. The mixed material can then be used for paving.
In addition to cold mixes for bituminous bound base layers, the plant can also produce mixes for cement-stabilized base layers and roller compacted concrete at rates of up to 240 tons per hour, Wirtgen says. “These construction materials are integrated in the road construction cycle as high-quality mixes. They can be used for applications ranging from highway, road and path construction to the construction of parking lots or industrial areas.”
The plant’s higher production speed is due to Wirtgen’s “double trough technology,” which doubles the processing speed. “The system enables precise, reliable and automatic addition of large amounts of hydraulic binding agents,” the company says. “As a result of this, the mix production process achieves the highest levels of efficiency and quality.”
The system also features automatic self-calibration and precision weighing for the constant addition of binding agents during the continuous mixing process, according to Wirtgen.
Milled recycled asphalt pavement or other granular material from old road surfaces and materials from the demolition of reinforced concrete can also be recycled and mixed.
“The 100% recycling rate enables substantial CO2 (emissions) reductions and energy savings, while simultaneously minimizing project costs and timeframes,” the company says.
The mixing plant is mounted to a flatbed semitrailer and has its own engine. It is designed to be quickly moved and set up at various locations.
WR series updates
Wirtgen’s WR cold recyclers are self-propelled machines that use a milling and mixing rotor and injection system to mill and granulate asphalt pavements and mix them with binder and water for new base paving layers. They can also be used for soil stabilization.
The company’s new Resource Efficiency System adds an automatic, satellite-based steering system that increases accuracy down to the centimeter, Wirtgen says. It also stores all of its data of important parameters for analysis and documentation. The data are also compatible with motor graders and compactors on the same project. When soil stabilizing, it collects data on such things as working width and depth, distance and area worked and fuel consumption.
Wirtgen has also developed a new VARIO injection bar for the WR series. It regulates the addition of water and binding agents based on such parameters as working width and depth, material density and the machine’s travel speed. The bars each have a max of 16 nozzles. The nozzles can be individually controlled to vary spraying width. The adjustable nozzles can also regulate injection pressure and the depth of the spray jets into the milled granulate, the company says. “The result is an even more even distribution of water, bitumen emulsion, or foamed bitumen throughout the entire mixing chamber.”