Automation of the production process
Quality improvement and simultaneous yield increase
The wind energy industry enjoys considerable growth potential. One of the largest manufacturers of wind turbines, Moventas, is ready to take full advantage of this situation – thanks also to investments in measuring technology from Carl Zeiss.
Several years ago, Moventas planned a new factory that should have the capacity to deliver thousands of planetary wheels annually. Prior to this, these components were manufactured in small batches manually and individually. Major changes were needed to take the next big step – the implementation of a serial process. A new quality management system, which would combine all tools and processes, was necessary. Taisto Kymäläinen, the responsible quality manager, and his team were tasked with conducting an in-depth analysis of internal processes and questioning all existing procedures. It also involved a price/performance comparison of all measuring machines and measuring solutions on the market. “When I saw the CenterMax coordinate measuring machine at Control 2006, I knew right away that it was the right solution for the Ikola plant,” says Taisto Kymäläinen. With this in mind, he took Carl Zeiss on board as a solutions partner. Looking back, it is safe to say that the recently opened Ikola plant has far exceeded its planned production of planetary wheels.
The quality of the gears in the planetary wheels is vital to the energy efficiency and service life of the wind turbines. The raw material – large steel blocks – are first tempered before being transported to pre-machining using automated guided vehicles. A data matrix code is assigned to each part during initial machining. Following pre-machining, the gear wheels are transferred to the hardening area where it is always warm and cozy – even in the winter. This provides the surfaces of the gear wheels with an extra hard shell.
The next step is to grind the hardened gears. During run-in of the grinding process, the first parts are measured on a manually fed CenterMax directly on the shopfloor. Volume production can begin once the quality has been ensured and the process set up. During serial production, a gantry robot – automated, of course – transports the components to the next quality inspection station after grinding, where another CenterMax waits. The gantry robot then moves the gear wheels to the different processing stations, where the gears are cleaned and their tempered surfaces inspected using the Barkhausen noise method. Once again, it's off to quality inspection – and CenterMax.
The heavy gear wheel is then placed in a special fixture on the CenterMax. The measurement starts automatically. The measuring results are transmitted to a database via communication with the cell. Each part inspected by the CenterMax is first sent to larger, automated warehouse where it waits until it is integrated into the gearbox. Overall, the system is a perfect example of a standardized automated system. With additional demand expected, this area is prepared for the expansion of the master-slave system. Gear evaluation with GEAR PRO is a key element of quality improvement and it ensures stable production. Statistical data can also be captured to simplify future processing. With the transition to mass production and the measures implemented, Moventas is well-prepared to meet the challenges of the future.
The first transmission gears were manufactured around 70 years ago in Jyvaskyla, Finland, at a time when wind power was most likely still considered science fiction. Back then, Moventas produced gears for the paper industry. At the beginning of the 1980s, the company began building gearboxes for small wind turbines. The merger of Valmet, Santasalo and Parkano Gears in 2000 laid the foundation for Moventas. Today, Moventas is active around the globe and has around 1300 employees, 700 in Jyvaskyla.