057-11 Lohr, 2011-06-28

Unparalleled Efficiency in Smelting

A pneumatic cylinder is the key element in the crust breaker, a tool used in the aluminum industry.

A pneumatic cylinder is the key element in the crust breaker, a tool used in the aluminum industry.

Rexroth improves aluminum production processes with the System Optimizer for its crust breaker component

One major challenge in primary aluminum production is the crust which constantly forms on the bath surface. To keep the aluminum production process going at a steady rate, it needs to be punctured by the crust breaker. Rexroth developed the System Optimizer for this process. It measures and monitors process data, thus controlling the processes in the potroom. As for the advantages over conventional systems: the System Optimizer from Rexroth provides data – for instance on the bath level – which results in improvements to the production process. With its highly precise controller, the pneumatic crust breaker is used exactly where it is needed to minimize contact with the bath. This improves production results, ensures efficient implementation, and optimizes the service life of the individual components.

The cyrolite crust that develops during the production process in the potroom needs to be broken up regularly. This ensures a successful production process resulting in high quality aluminum. A pneumatic cylinder is used to chisel through the surface of the crust from above. The patented System Optimizer was developed to ensure that the cylinder piston is submerged only for the right amount of time and exactly where it is needed. The System Optimizer controls the cylinder, retracting it as soon as it makes contact with the bath. This prevents the accumulation of deposits on the piston and rod.

Equipped with bath surface sensing technology, the System Optimizer is a unique and highly reliable system. The pot controller operates with two signals: one signal for motion and the other for pressure. The crust module, which takes a precise measurement of the bath level in the pot, sends direct signals to the pot controller that simultaneously indicate the piston’s contact with the bath and its position. This enables a direct display of the process status in the bath.

The system operates using low pressure and also saves compressed air with cylinder strokes that are shorter on the average compared to conventional systems, thus conserving energy. The robust ISO cylinder, which is predestined for use in this harsh environment, is a diverse, adaptable component with a high load capacity. The low-maintenance cylinder is made of aluminum, with steel end covers. Its physical form guarantees the secure, direct mounting of the valves. The cylinder is optionally available with different scrapers, cushioning kits and sensors.

Rexroth also offers robust maintenance units and additional accessories that optimize compressed air flow, even under these harsh conditions. This ensures the proper functioning of the pneumatic components at all times.

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 34,900 associates generated approximately 5.1 billion euros in revenue in 2010.

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The Bosch Group is a leading global supplier of technology and services. In the areas of automotive and industrial technology, consumer goods, and building technology, some 285,000 associates generated sales of 47.3 billion euros in fiscal 2010. The Bosch Group comprises Robert Bosch GmbH and its more than 350 subsidiaries and regional companies in over 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 3.8 billion euros for research and development in 2010, and applied for over 3,800 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
Maria-Theresien-Straße 23
97816 Lohr am Main
Phone: +49 9352 18-1573