067-12 Lohr, 2012-09-18

Intelligent cooling systems recognize wear

Intelligent cooling systems from Rexroth

Intelligent cooling systems from Rexroth continuously capture and analyze fan drive data. The drive controller software recognizes mechanical wear before a failure. This leaves enough time to schedule

All over the world, mobility and the desire for fast transportation connections are on the rise. Rail transportation is playing an increasingly important role in these developments, offering eco-friendly and cost-effective means of mass transportation. The current trend is toward electric rail vehicles. They accelerate more quickly than diesel vehicles which leads to shorter travel times. One important parameter in terms of the aspects of life cycle costs and reliability – which are crucial to rail operators – is the cooling technology used for traction equipment. A failure on track leads to substantial costs and disruptions in regular rail service. Decentralized intelligent cooling systems such as those that Rexroth plans to unveil at InnoTrans continuously capture and analyze fan drive data. The drive controller software recognizes mechanical wear before a failure occurs and sends a warning notice to the train driver. This leaves enough time to continue train operations and schedule appropriate maintenance.

As for electric rail vehicles, most manufacturers have relied so far on centrally controlled cooling systems for components of traction systems like, transformers, traction inverters, and other components. This increases complexity. As a result, manufacturers are increasingly shifting to decentralized intelligent drives, and now they are tapping into numerous additional functions which they can use for a significant reduction of life cycle costs. For example, the cooling systems recently developed by Rexroth recognize whether the radiator is soiled.

Imbalances in the fan wheel are another common source of failures in practice. These imbalances amplify quickly, and can lead to bearing damage or, in extreme cases, even to a damage of fan wheel. Beyond the operational disturbance, this also generates considerable additional costs for repairs. Precisely this problem can be dependably prevented by the condition monitoring functions built into the Rexroth cooling system. They continuously analyze motor data for the fan drive during operation. As soon as an imbalance occurs, the software warns the train control system or driver on multiple levels. This means the condition monitoring feature prevents train failures and reduces maintenance costs, since technicians are able to correct minor imbalances with little effort and expense.

In regular train operations, the operators benefit from demand-driven cooling without any damaging materials. The pole changing motors that have been common so far generate abrupt changes of state when switching at rotational speeds specified by their design. This creates strain on mechanical components and leads to wear. The decentralized intelligent cooling system, by contrast, independently analyzes sensor data such as exterior and motor temperature and stagelessly regulates fan speed by a frequency converter. This protects mechanical components and reduces life cycle costs even further.

Rexroth has been a highly regarded system partner to the global railway industry for decades. Beyond intelligent cooling systems for diesel and electric driven rail vehicles, many manufacturers also rely on electrical, hydraulic, pneumatic, and mechanical components from Rexroth that are certified according to international rail standards.

Bosch Rexroth AG is one of the world’s leading specialists in the field of drive and control technologies. Under the Rexroth brand name, the company supplies more than 500,000 customers with tailored solutions for driving, controlling, and moving. Bosch Rexroth is a partner for Mobile Applications, Machinery Applications and Engineering, Factory Automation and Renewable Energies. The company provides customized solutions tailored to the needs and specifications of each individual market. As The Drive & Control Company, Bosch Rexroth develops, produces, and sells components and systems in over 80 countries. As part of the Bosch Group, Bosch Rexroth and its 38,400 associates generated approximately 6.4 billion euros in revenue in 2011.

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The Bosch Group is a leading global supplier of technology and services. According to preliminary figures, more than 300,000 associates generated sales of 51.5 billion euros in the areas of automotive and industrial technology, consumer goods, and building technology in fiscal 2011. The Bosch Group comprises Robert Bosch GmbH and its more than 350 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. Bosch spent more than 4 billion euros for research and development in 2011, and applied for over 4,100 patents worldwide. With all its products and services, Bosch enhances the quality of life by providing solutions which are both innovative and beneficial.

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Susanne Herzlieb
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