Function
The bedplate supports the drive train and the rest of the nacelle components and transfers loads from the rotor to the tower.
What it costs*
The bedplate cost varies significantly for different nacelle layouts.
Who supplies them
Bedplates are normally cast SG iron, with a steel fabricated rear section.
Casting: Fonderia Vigevanese, MeuselWitz Guss, Sakana, Siempelkamp and Silbitz. Only some can manufacture the largest bedplates for offshore turbines today.
Fabrications: A reasonable range of steel fabricators exist capable of bedplate manufacture.
Key facts
Frequently, bedplates are manufactured in two parts. In a conventional nacelle layout, the heavier section supports the gearbox [T.1.4] and the yaw system [T.1.8], transfers loads from the rotor [T.2] to the tower [T.3] and is frequently cast. A lighter rear section supports the generator [T.1.5] and other components at the rear of the nacelle and is normally fabricated. For a direct-drive turbine, the generator takes the place of the gearbox. Some nacelles have a more integrated layout with less requirement for a rear bedplate.
Bedplates are designed by the wind turbine supplier and generally manufactured by external suppliers. Design considerations include fatigue and extreme loads, stiffness and assembly, and maintainability features such as access ways to critical components.
Once manufactured, the items are machined, shot blasted, metal sprayed and epoxy painted before delivery to the wind turbine supplier. Material is typically EN-GJS-400-18U-LT grade SG iron or a standard 355-grade steel.
What’s in it
- Large cast SG iron or fabricated steel structure
- Machining and painting