With the latest generation of hydraulic power packs, users will benefit from easier maintenance, lower running costs and unsurpassed connectivity, says Bosch Rexroth’s David Stubbs.
Hydraulic power units are sometimes viewed as just a way to generate hydraulic pressure and flow for powering machinery. With all the interest today in Industry 4.0, the Factory of the Future and the Internet of Things (IoT), Bosch Rexroth set out to bring the hydraulic power unit up to date.
It took a clean sheet approach to the design, with a view to improving energy efficiency, connectivity, condition monitoring and space requirements.
The result, CytroBox, promises significant advantages for applications requiring up to 30kW. Thanks to integrated IoT technologies, it paves the way for implementing Industry 4.0 concepts. Moreover, the benefits inherent in CytroBox result in a much lower total cost of ownership.
Improved energy efficiency
A variable-speed controller and water-cooled synchronous servo motor optimise current consumption and improve energy efficiency substantially. The variable-speed pump drive adjusts energy requirements as needed. Speed is reduced under partial or no load to save energy; conversely, it is increased under full load with a highly dynamic response. This saves up to 60% of energy compared with conventional power units. The synchronous motor is also as much as 80% smaller than a comparable asynchronous motor, saving space and weight.
A new design of high-efficiency manifold block is cast using 3D-printed sand cores. The manifold block is up to 40% smaller and boasts improved flow channels. As a result, oil flow is improved and pressure losses reduced. CytroBox also features an active dewatering unit to protect against external contamination.
Connected for condition monitoring
Equipped with sensors and open interfaces, CytroBox is ready for use in connected environments. As standard, sensors monitor control pressure, oil level, temperature, and pressure drop across the filter. Optional sensors monitor pump leakage, water content, dissolved air, dirt particles and oil pan leakage. Sensor data is processed by the drive controller and, with the help of the Open Core Interface, it can also be integrated in the overall machine concept.
CytroBox is offered with a choice of connectivity options so users can achieve the potential of IoT technologies. CytroConnect is a free service for monitoring performance via a smartphone, tablet or any web browser. Alternatively, there are two subscription services: CytroConnect Maintain adds trigger points (alarms) and CytroConnect Predict uses artificial intelligence for predictive maintenance and preventing unplanned downtime. All information – from the component and operating status or forthcoming maintenance work, to predictive maintenance analysis – is available via Rexroth’s online diagnostics network (ODiN) so it is always close to hand.
Compact and quiet
Depending on the power rating, CytroBox’s footprint is up to 75% smaller than conventional alternatives thanks to a “fridgefreezer” layout with the hydraulic components at the bottom and electrical equipment above. The compact configuration saves valuable floor space and makes it easy to retrofit the CytroBox to existing hydraulic systems. Use of computational fluid dynamics at the design stage resulted in a reservoir that is 75% smaller and optimises flow and degassing. Oil volume is reduced from 600 litres to 150 litres, which gives a direct saving in oil costs and disposal costs when oil changes are undertaken.
With everything built into a cabinet-style enclosure with integral sound insulation, there is no need for a separate acoustic enclosure. Furthermore, the motor pump group is fixed rigidly to a polymer-concrete foundation to reduce structure-borne noise. The damping bearings that would typically transmit the noise to the tank are completely eliminated. Even at full load, CytroBox noise emissions are less than 75 dB (A), compared with an average of 85 dB (A) from comparable power units. Despite the cabinet-style configuration and integrated soundproofing, CytroBox still provides easy access for maintenance.
It is predicted that within two years, the total cost of ownership for a CytroBox hydraulic power unit will be lower than that for a conventional unit. The continuing benefits, year-on-year, will have a positive impact on profitability.
www.boschrexroth.co.uk
David.Stubbs@boschrexroth.co.uk | +44 (0)1285 86-3028