Low-emissions, low fuel consumption and energy-efficient wheel loaders are becoming ever more important to the building industry and construction machinery manufacturers. bauma, billed as the “World’s Leading Trade Fair for Construction Machinery, Building Material Machines, Mining Machines, Construction Vehicles and Construction Equipment,” April 11–17 at the Messe München exhibition center in Munich, will spotlight loader engineering and environmental progress.
Since the 1999 Exhaust Emissions Directive introduction, the construction machinery industry has drastically reduced emissions from its products. According to the German Engineering Federation (VDMA), emissions of nitric oxide and diesel particulates have been reduced by more than 95 percent.
“With the aim of optimizing energy efficiency and obtaining the best possible work result, these days construction machines decide for themselves what is most economical in a particular work process: to transfer the power to the wheels mechanically or hydraulically,” says VDMA Construction Machinery and Building Materials Machinery Association Managing Director Joachim Schmid. “The drive chain delivers only as much power as is needed, energy is stored and delivered as required. For years the ‘eco mode’ has been standard in many types of machinery.”
Despite what has already been achieved, he adds, there is still scope for further improvements to transmission systems in construction machinery—especially when manufacturers and suppliers combine their expertise. This was the case in the TEAM project (development of technologies for energy-saving transmission systems in mobile machinery), which culminated last year in the presentation of a “green wheel loader.”
For three years, 18 machinery manufacturers and component suppliers—among them Caterpillar, Danfoss, Deutz, Hydac, and Rexroth Bosch—five university institutes, and the VDMA worked on an innovative operating strategy for linking parts of the drive system. A demonstration wheel loader combines an optimized diesel engine, powersplit transmission system, displacement-controlled working hydraulics, and a hydrostatic hybrid system in a new drive chain. In comparison to a current series machine, this new development is more than 10 percent more fuel-efficient in practical operation. At bauma, further information and details about this development will be presented live in the “Research Initiative” (Hall B0).
Special power-split transmissions are gaining ground in wheeled loaders. Notes Prof. Dr.-Ing. Marcus Geimer, chair in Mobile Machinery at the Karlsruhe Institute for Technology, “In a wide variety of operations, these transmission systems deliver improved efficiency as compared to hydrostatic transmissions or switchable converter drives.” Corresponding prototypes and designs have already been presented at various specialist conferences, he adds, noting, “Now I am keen to see which manufacturers will showcase these components at bauma 2016.” — www.bauma.de