Components for the wind industry
Liebherr is the only manufacturer worldwide that is not only able to supply individual components as slewing bearings, slewing drives, electric motors and hydraulic cylinders, but able to supply hydraulic and electromechanical pitch systems and electromechanical yaw systems for wind turbines.
An important element of the cooperation with customers from all over the world is the applied application-specific engineering necessary for adapting and matching the individual components to each other. Liebherr works together with virtually all well-known turbine manufacturers and to date has supplied components for more than 15,000 wind turbines. The product portfolio covers components for 800 kW installations up to solutions for multi-megawatt turbines for offshore wind farms.
Liebherr produces well-engineered mechanical systems for rotor blade adjustment. Electric pitch systems are based on one or more mechanical gear units with electric motor, which drive a geared large diameter slewing bearing.
Hydraulic pitch systems are based on one or more hydraulic cylinders and a slewing ring bearing without gears to adjust the rotor blade position. In either case, the precise positioning of the rotor blades results in maximum energy yield.
In pitch systems, the following components from the Liebherr portfolio can be applied:
Three-row roller bearings for higher load capacity and more cost efficiency
Wind turbines are growing steadily in an effort to attain higher energy yields. The options of adapting existing designs to the growing dimensions and more demanding load profiles has however limits - particularly in regard to rotor blade bearings. Therefore, in addition to the current single-row and double-row four-point bearings, Liebherr now also offers three-row roller bearings for pitch systems. This highly increases the potential in terms of dimensioning and load capacity.
Depending on the specific system design, up to twelve or more high-performance planetary gearboxes drive a slewing bearing and ensure precises as well as reliable wind direction tracking. Liebherr configures the entire yaw system, including the necessary electric motors, precisely to the needs of the customers. This guarantees a high level of system availability.
The following components from the Liebherr portfolio are ideally suited for use with yaw systems:
Implementation within the wind turbine
Based on a continuous quality management and the use of cutting-edge technologies, components by Liebherr meet the highest demands regarding quality and performance.
Product and system expertise
The right design and analysis of a component is decisive for its reliability and service life. For multi-megawatt wind turbines a design using Finite Element Methods (FEM) is essential, as the sensitivity to strain increases the larger the system gets. In addition, defined approval processes for new and further developments ensure optimal product configuration and thus high reliability.
High level of vertical integration
In order to ensure consistent high quality and reliability, all manufacturing processes must be optimally aligned. Hence why Liebherr improves all production processes on an ongoing basis and continually invests in cutting-edge production facilities.
Reliable components with a consistently high quality are particularly important for wind turbines in order to avoid long production downtimes and high logistics costs. To ensure that the quality standards achieved in the construction using Finite Element Methods (FEM) and Failure Mode Effects Analysis (FMEA) are also maintained in subsequent processes, all company processes are designed to maintain quality.
Test bench for wind turbine main bearings
We test our main bearings for wind turbines on a specially developed test bench. In order to realistically imitate the rigidity conditions of the application, a machine carrier from a wind turbine is used as an adjacent construction.Learn more
Quality testing of slewing bearings
Large diameter bearings with a diameter of up to 6,000 mm are measured and tested in a fully air-conditioning measuring laboratory.
Wide range of slewing bearings
Slewing bearings from Liebherr are available in different designs and a diameter range from 400 mm to 9,500 mm. Larger sizes are possible in a segmented design.
Slewing bearings for wind turbines
Liebherr produces large diameter slewing bearings for the adjustment of rotor blades and yaws in wind turbines. They can be designed as single-row or two-row four point bearings with external or internal gearing.
Slewing drives for wind turbines
Slewing drives from Liebherr for the adjustment of rotor blades and yaws in wind turbines are characterized by reliability and precise positioning.
Slewing bearings for pitch adjustment
Installation of large diameter slewing bearings for pitch adjustment at a customer's factory.
Stress tests in real conditions
Stresses throughout the entire service life of the gearbox are simulated in test runs.