In the energy sector, the function of wind turbines is to convert kinetic energy of wind into mechanical energy.
The principle is simple: the wind turns the blades, like a pinwheel, which in return rotates the generator transforming mechanical energy into electrical energy thanks to a dynamo.
Proper lubrication is essential to ensure maximum reliability and facilitate the correct movement of the blades, which must also cope with difficult environmental conditions.
During operation, components are subjected to high mechanical loads in order to allow the movement of the blades, as well as reduce contamination, vibration, and humidity, which can negatively affect the operation of the wind turbines.
The main components involved are bearings and gears, which are responsible for the rotatory movement and therefore must be properly lubricated.
To achieve this, the installation of an automatic lubrication system is necessary, which constantly provides the correct amount of lubricant at the proper time and at the right location, this protects components from contaminants
The following image shows the lubrication points of the wind turbines, and the different types of lubrication systems:
RED POINT - These points are under frequent operation and need to be lubricated to prevent premature failure. The system is setup for frequent lubrication at regular intervals.
BLUE POINT - Consists of the rim lubrication located in the lower part of the nacelle. A special type of gear/pinion applicator is used to distribute grease uniformly at the final
lubrication point
GREEN POINT- Indicates the support used to modify the single blade inclination (pitch). This point is subject to both a centrifugal force and load from the wind force working during hub rotation.
The entire lubrication system must be able to resist to centrifugal force, loading, and avoid reservoir cavitation during operation. A pump fitted with a spring loaded follower plate prevents this problem.
Each system is designed in respect to the requirements of wind turbines, and is chosen based on the following factors such as:
- Nacelle temperature
- Environmental conditions
- Number of lubrication points
- Quantity of lubricant for each point
The type of lubricant used is grease, in a system with the following components, an electric pump, a progressive divider, and a lubrication pinion.
Grease has a consistency that best protects the components from external agents, in addition to having a long-lasting effectiveness.
In general, the installation of an automatic lubrication system leads to an increase in reliability and reducing the risk of downtime caused by damage of components.
By providing a precise amount of lubricant to the proper location, at the right time, it is possible to obtain an increase in the life cycle of the components, as well as prolonging the maintenance intervals.
The benefits provided by a lubrication system for wind turbines:
- Increasing in turbine life and bearings
- Protection from corrosion and atmospheric agents
- Reduction of bearing wear
- Excellent distribution of lubricant
- No waste of grease
- Reduction of maintenance costs
