Roller mills are at the heart of Swissmill's production process. When the company decided to replace all its roller mills and the motors that power them, it selected ABB to supply the new motors. ABB customized the motors to meet Swissmill’s safety, efficiency and installation requirements. To enable maximized availability and uptime, the motors are digitally connected to ABB Ability™ Condition Monitoring for powertrains.
Swissmill is the largest mill company in Switzerland and processes around 30 percent of the grain used in the country. Visitors to Zurich cannot miss the 118-meter Swissmill Tower, which is not only a major city landmark but also the tallest grain elevator in the world. With a capacity of 35,000 tons, it plays a vital role as part of Switzerland’s emergency food reserves.
High-tech mill
The mill itself is housed in a five-storey building adjacent to the tower. Incoming grain is first cleaned and then ground by roller mills. Pairs of rollers operating at different speeds break the grain into its constituent parts. The intermediate products are transported through a system of pneumatic tubes for further processing.
Swissmill has six separate milling lines: two for wheat, one each for durum wheat, maize and oats, and one specialty line. Electric motors are used throughout the mill, with a total of around 1,500 motors installed. The mill is a long-standing ABB customer, and about three-quarters of the motors were supplied by ABB or its predecessor company.
Good support and fast response
“We have a large installed base of ABB motors, and they run very well," says Simon Künzle, Head of Technology at Swissmill. “We also get good support from ABB Switzerland, and they respond quickly when we contact them.”
“When we decided to replace the roller mills, we chose ABB to supply the motors. We have 36 roller mills, and each mill is powered by two motors ranging in output from 7.5 to 22 kilowatts. The new motors had to meet our special requirements regarding safety, energy efficiency and mechanical installation.”
‘Plug & play’ motors
“ATEX motors ensure the greatest possible safety in potentially dusty mill environments,” says Huy-Hour Lor, Product Manager for Low Voltage Motors at ABB Switzerland. “To meet Swissmill’s safety and efficiency requirements we fine-tuned our existing ATEX motors to meet the demands of the IE3 efficiency class.”
“Regarding installation, the motors are actually installed below the mills themselves – they are suspended from the ceiling of the space below. Swissmill and its technology partner Bühler, which supplies the mills, requested a one-to-one exchange of the motors, so the mechanical set-up wouldn’t have to be altered. Our low voltage motors factory in Finland customized the motors to make them into ‘plug & play’ products that meet all the requirements. This enabled them to be installed in place of the old motors, and it saved the customer a lot of time and effort during the installation process.”
Simon Künzle with one of the new digitally connected motors from ABB. 
Swissmill has installed 36 new Bühler roller mills. 
Roller mill drive system. Each mill is powered by two ABB motors that are installed below. 
The Swissmill Tower in Zurich is the world’s tallest grain elevator.
Prioritizing high availability
"Our top priority is availability," Künzle states. “We operate almost a third of Switzerland's milling capacity, and if that became unavailable the consequences for the country’s food supplies would be drastic.”
“In order to maximize availability, it naturally makes sense to take action as early as possible - before a failure occurs. For this reason our roller mill motors are digitally connected to ABB’s remote condition monitoring service.”
The remote monitoring service tracks the health and performance of motor-driven systems, enabling customers to make better decisions that maximize uptime as well as optimizing performance and energy efficiency. ABB’s experts provide deep insights into the operation of the customer’s powertrain. With the service, Swissmill’s staff can check the status of their motors at any time on a computer screen or mobile phone, and they receive an immediate alert if the system detects a potential issue.
“Here at Swissmill we produce a significant part of the flour used in Switzerland. Our job is to process grain as reliably and sustainably as we can. Our new, digitally connected motors from ABB make an important contribution to our work,” Künzle concludes.
