Performance for mobile working machines

Performance for mobile working machines
Marginal Column

November 2016


The hydrostatic travel drives and implement hydraulics of the future should be economical, quiet, yet just as powerful. Bosch Rexroth is therefore offering a holistic system of high-performance components for mobile working machines: for applications in the field, the construction site, the container terminal, or for municipal operations.

As a solution provider and OEM system partner, Bosch Rexroth is driving the electronification of hydraulics in mobile working machines. The physical benefits of hydraulics are combined with the flexibility of software-based controllers. This also makes it possible to store energy and supply it on demand. According to Bertram Hoffmann, member of the Executive Board of Bosch Rexroth AG and responsible for the Business Unit Mobile Applications: “Our hydraulics for working functions and travel drives are already making a significant contribution to reducing diesel consumption and thus the exhaust emissions from mobile working machines. It is important that we maintain the usual performance and agility of the hydraulics or, if the customer so wishes, even increase it.”

In addition to typical application components, Bosch Rexroth’s design-to-region concept develops and designs solutions that can be adapted to regional requirements. One example is EDIS, the Energy Demand-oriented Implement System. It is designed for the medium-sized wheeled loader segment of the Chinese market, and a purely hydraulically or electrically controlled variable displacement pump significantly increases energy efficiency and reduces diesel fuel consumption by up to 10 percent.

Across country with hydraulic motors

In combination with highly efficient hydraulic motors and the appropriate software, Rexroth offers complete solutions which reduce both consumption and exhaust gas emissions and improve driving comfort at the same time. The standard travel drive software DRC, for example, makes a holistic drive control for the effective interaction of all travel drive components possible. In addition, when there is a lower performance requirement, integrated eco functions reduce the machine’s fuel consumption and noise emissions by up to 20 percent. The software also supports the new series of A4VG axial piston variable pumps, which with integrated sensors, anticipate the future requirements of electronified travel drives.

At the same time, efficient and economical solutions can be implemented with new concepts for hydrostatic travel drives. The Hydraulic Traction Assistant (HTA) improves the maneuverability of trucks on snow, ice, mud, and unpaved tracks. Radial piston motors on the wheel hub replace the classical mechanical 4-wheel drive, saving 400 kg of weight and reducing consumption.

Gentle power in work mode

A new modular control block with load-pressure independent flow sharing offers significantly improved energy efficiency thanks to lower pressure losses. Designed for bulldozers and wheeled loaders of up to 16 tons, the control block with the abbreviation RS15WL lowers exhaust emissions in addition to diesel consumption. Energy can also be saved when it comes to agricultural machinery. To date, tractors in the 90 horsepower class were usually equipped with fixed pumps for cost reasons, however, the axial piston variable pump A1VO delivers power as needed and thus reduces diesel consumption by up to 15 percent in the partial load range.

Maintain rather than repair

On the issue of connectivity, Bosch Rexroth is focusing on increasing the availability of all machines in operation. A whole range of sensors for position, temperature or pressure are integrated into the hydraulics in order to capture and forward information about the operating status. The A4VG axial piston variable pump shows the effects of this electronification. It sends previously collected sensor data to the control unit of the machine via an open interface. The control unit communicates via the Internet with the cloud, for example that of the OEM. The machine’s status is thus transparent every minute. Expensive downtimes at the peak of the season are a thing of the past, for with preventative maintenance, high availability is now guaranteed.

Mobile working machines: Electronics boost efficiency

“We need smart hydraulic systems.”