PI 026-16 Lohr am Main, 2016-04-11

Drum drive: safe, quiet, energy-efficient

Especially compact and light: the new A4VGT axial piston variable pump from Rexroth for drum drives of concrete mixers.

New Rexroth axial piston variable pump for drum drives of concrete mixers

The new A4VGT series 34 axial piston variable pump from Rexroth fulfills the increased safety requirements for drum drives of concrete mixers. Moreover, the additional frame size allows for a reduction in the noise level and diesel consumption. The new pump sets new standards in compactness and low weight.

Due to the ISO13849 machinery directive, there are stricter requirements in the European Union for the functional safety of hydraulic units that drive mixer drums. The Rexroth A4VGT series 34 axial piston variable pump with special function elements such as sequence valves and neutral position switches fulfills these requirements. Rexroth has determined and documented the required reliability parameters for functional safety for these elements and the proportional electric control (EP). Therefore, designers can configure safe drum drives according to the correct standards and with little effort.

The variable pump with axial piston rotary group in swashplate design is intended for a maximum pressure of 420 bar in closed circuits. In addition to the previous frame sizes 71 and 90, Rexroth has also developed a version with 115 ccm displacement. With it, machine manufacturers can lower the rotational speed of the diesel engine in stationary operation, without reducing the speed of the drum drive. This lowers the average noise emissions and the diesel consumption during waiting times on building sites.

Rexroth engineers placed great value on weight savings and compact dimensions during the re-development. For frame size 90, they were able to reduce the weight by more than an eighth in comparison to conventional products on the market. Frame size 115 weighs eight kilograms less than comparable products. The series even achieves new benchmarks in its dimensions. Depending on the size, the installation length ranges from only 301 to 317 mm.

Tailored to the new A4VGT variable pump, Rexroth offers the A2FMT series 70 fixed motor unit – an efficient drive solution for working hydraulics.

Economical, precise, safe, and energy efficient: drive and control technology from Bosch Rexroth moves machines and systems of any size. The company bundles global application experience in the market segments of Mobile Applications, Machinery Applications and Engineering, and Factory Automation to develop innovative components as well as tailored system solutions and services. Bosch Rexroth offers its customers hydraulics, electric drives and controls, gear technology, and linear motion and assembly technology all from one source. With locations in over 80 countries, more than 33,700 associates generated sales revenue of approximately 5.6 billion euros in 2014.

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The Bosch Group is a leading global supplier of technology and services. It employs roughly 375,000 associates worldwide (as of December 31, 2015). According to preliminary figures, the company generated sales of more than 70 billion euros in 2015. Its operations are divided into four business sectors: Mobility Solutions, Industrial Technology, Consumer Goods, and Energy and Building Technology. The Bosch Group comprises Robert Bosch GmbH and its roughly 440 subsidiaries and regional companies in some 60 countries. If its sales and service partners are included, then Bosch is represented in roughly 150 countries. This worldwide development, manufacturing, and sales network is the foundation for further growth. In 2015, Bosch applied for some 5,400 patents worldwide. The Bosch Group’s strategic objective is to deliver innovations for a connected life. Bosch improves quality of life worldwide with products and services that are innovative and spark enthusiasm. In short, Bosch creates technology that is “Invented for life.”

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Susanne Herzlieb
Maria-Theresien-Straße 23
97816 Lohr am Main
Phone: +49 9352 18-1573

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