Power generation requires uninterrupted bearing service. The ball and roller bearings for the pumps, compressors, electric motors and drives must meet critical internal clearances, cage designs and Abec precision class. Pillow Block bearings have to be a design that allows for easy and prompt replacement.
Wind Turbines/Harnessing the Wind
The centuries old dream of harnessing the wind efficiently is now a reality. The Wind turbines of today often stand 250 feet in the air and are mechanical and technical marvels that rely on bearings in their key components:
A generator operating in the nacelle of a wind turbine is subjected to significantly greater vibration loads than its counterpart on the ground. This additional permanent load has a negative influence on the cages and places a strain on the lubricant.
In the design of bearings for a generator, it is not only the size and design that play an important role. Special attention must be paid to the lubrication and protection against possible current passage.
The bearing arrangement of a generator generally contains a combination of deep groove ball bearings or cylindrical roller bearings.The passage of current in a wind turbine generator can cause serious damage to the raceways of bearings in the form of melt craters and false brinelling. It is advised to use current insulated bearings in many applications.
Wind tracking and Blade adjustment
It is critical that the turbines be aligned optimally to the wind. This is controlled by:
Blade bearings (pitch bearings): In order to control the power output of the wind turbine, the blade angle must always be adjusted to the wind speed via the rotary motion of the blade bearing. Single or double-row four point contact bearings with or without gear teeth on the inner or outer ring are used here.
Yaw bearing: A slewing ring is required in order to adjust the position of the nacelle to the wind direction. The wind load and the dynamic inertia forces are transferred via the raceways and the screw connections into the tower head. Single or double row four point contact bearings are used here.
Blade adjustment: The rotor angle can be adjusted using electric or hydraulic systems. These use sealed spherical bushings that have corrosion protection.