Schaeffler Group Presented Innovative Bearings For Wind Turbines

At the WindEnergy trade show, which took place from May 16 to 19 in Hamburg, Schaeffler Group Industrial presented a wide spectrum of innovative bearings for wind turbines with its main brands INA and FAG. ¡°As a full-range supplier we can provide our customers with all solutions from one source,¡± Gunnar Simm stated during a press interview. Simm is Head of Application Engineering and Product Design within Schaeffler Group Industrial¡¯s Power Transmission and Railway division. ¡°In bearing development for this field of application, it is extremely important to take into account the entire wind turbine system with all the various interacting drive train components. Only this will make it possible to significantly increase the reliability and economic efficiency of wind turbines.¡± To this end, the company invests massively in extending its engineering capacities. ¡°The bearings used in this field are becoming larger and larger,¡± said Simm. ¡°This is why we start off by studying the operating conditions very intensely, for instance through measurement campaigns. Together with the customers we work out failure mode and effects analyses in order to minimize possible risks with the help of innovative and reliable solutions.¡± An especially innovative solution is the single-bearing concept for the rotor head which was developed for MULTIBRID¡¯s 5-MW offshore turbine. It has an outside diameter of 3200 mm, a bore diameter of 2620 mm, measures 485 mm in width and weighs approximately 7200 kg. Designed in accordance with the MULTIBRID drive train concept, the turbine solution features a rotor hub that is directly supported by a large rolling bearing in the machine housing. The drive train is a compact integrated gearbox/generator unit. The advantage of this concept is its clearly reduced weight. Thanks to the absence of the high-speed gear stage, the tower head has a compa-rably low weight of only 300 tons. This makes it possible to preassemble the facility on land so that the nacelle can be hoisted to the tower at sea with only one lift. In order to ensure the economic maintenance of the facility, a condition monitoring concept was drawn up in cooperation with the Schaeffler subsidiary FAG Industrial Services (F¡¯IS). It provides for continuous monitoring of bearings via numerous sen-sors. In the event of readings deviating from specified norms, remedial action is taken without delay to avoid unplanned downtime. At the WindEnergy exhibition, the company also presented a maintenance-free spherical plain bearing used for rotor blade adjustment in hydraulic cylinders. Ac-cording to Gunnar Simm, this spherical plain bearing is lined with ELGOGLIDE® sliding and thus offers especially low friction. Lip seals on both sides protect the bearing against contamination and are highly resistant to humidity. As standard, the bearing was designed for shaft diameters from 17 to 300 mm and it is ideally suited for operating temperatures from -30 ¡ãC to +130 ¡ãC. These properties ensure its long service life. Depending on the installation conditions, special designs can also be supplied. Another highlight on the Schaeffler Group stand was the plummer block housing for the main rotor support in 1.5-MW turbines. This unit consists of a spherical roller bearing with shaft nut as well as additional parts and has been adapted for use in wind turbines. The bearing accommodates loads in all directions, compensates for slight misalignment and shaft deflection, and enables easy relubrication and installation. This ensures high operational reliability and long life. Schaeffler Group Industrial offers all products for main rotor supports from one source.