Steel processing is a truly global business, and Siemens VAI enjoys great success in translating its innovations into international cooperation. The company is a leader in processes for sustainable steel production, a field in which Hohenbichler plays a significant role. For example, in cooperation with partner companies he developed processes for manufacturing sheet steel in a continuous casting and rolling process. In contrast to conventional steel mills, flowing hot raw steel is not poured into slab ingots which are then reheated for rolling, but rather rolled immediately after casting. "Because the facility processes the steel in a continuous strand, it enjoys up to 45 percent energy savings," explains Hohenbichler. To achieve this, sensors and process computers must control the system in real time, using process technology that Hochenbichler has developed.

Hohenbichler’s strength lies in finding solutions to supposedly insoluble problems. For example, he finds improvements even for the ostensibly "mature" technologies found in hot and cold rolling mills. Steel slabs weighing 25 tons each are first hot rolled and then passed through five sequential sets of rolling mill stands to produce sheets that are 0.4 to 2 mm thick. In the process, the frames carrying the rollers can begin to vibrate greatly. To prevent this, the control electronics reduce the speed of the entire facility at the first sign of vibration, which of course diminishes the production rate. "But it's even worse when the steel bands tear as a result of vibrations, because that brings the entire facility to a standstill until the bands are again threaded, beginning at the front of the line," explains Hohenbichler. And in the very worst case, vibrations can cause major damage to the facility.

Hohenbichler and his colleagues have invented a method of active vibration damping that can be retrofitted to existing installations. Additional sensors instantly recognize the onset of vibration and pass the information to the control system. There, the new control algorithms, which operate at a very high cycle rate, calculate the appropriate control commands, which for example may result in the application of force to hydraulic cylinders. "This mechatronic solution is ideal for modernizing installations," says Hohenbichler.

Another problem in rolling mills is the contamination of rollers, which affects the quality of millimeter-thin sheet steel. Previously, the entire facility had to be shut down in order to locate and remove contaminants from the rollers. Using new sensors and new control technology, the control system now immediately recognizes contaminants and can remove them while the mill is in operation, using specially developed cleaning apparatus. Such cross-functional solutions employing electronics and mechanics are Hohenbichler’s specialty.

The inventor is also involved with issues that solely involve data processing. For years, he and his colleagues have been experimenting with methods of combining the many hundreds of individual signals that are continuously generated by sensors in a cold rolling mill into an overarching monitoring system. To date, the signals have only served their own specific monitoring and control mechanisms. "But in summary, the overall evaluation is that there is great potential for deriving meaningful knowledge about the operation and condition of a facility from the gigabytes of available data," says Hohenbichler. That’s because, in his experience, no facility runs so smoothly that it can’t be improved.