Thanks to constant advances in technology, there has never been a better time to depend on wind turbines. More so than ever before, wind farm owners have the means to accurately predict potential failures with their equipment and deduce when their turbines will need maintenance performed, allowing them to protect their asset and extend its functional life.
Intriguingly, the turbine equipment made by turbine suppliers is becoming more and more robust, further helping wind farm owners. An example of this is GE’s recent announcement that they will take gearbox support to 2.2MW.
GE’s evolved system features a unique setup for bearing housing, as it keeps two bearings and a main shaft in the main carrier, while supplementing that with a gearbox connected to the main shaft rear.
That said, there is still not a “one-size-fits-all” solution in regards to designs of main shafts and bearing supports; in fact, turbine owners still have a bevy of options to choose from, in regards to how they want their turbine’s main shaft and bearing support arranged. Specifically, they can choose between a three-point gearbox (like GE’s new release), two-bearing alternatives and single cast options. Let’s briefly look at the advantages of each option.
Advantages of the Three-Point Gearbox
The three-point gearbox offers a slew of advantages. For starters, its design includes a single rotor bearing, meaning less parts and cheaper prices, since it will not cost as much to build as a two-bearing model. In addition, GE’s three-point gearbox consists of the main shaft rotating in motion in a cast chassis, meaning accurate concentric bearing bores. As such, the transfer of the rotor torque into the gearbox is seamless, and, (according to Wind Power Monthly) “a full absorbance of rotor-induced axial forces, as there is no free play in the unit.”
However, there are fallbacks to the three-point gearbox, well at least potential fallbacks. For example, if it is not designed properly, it could cause the rotor to bend when entering the gearbox, which could cause detrimental damage to the gearbox.
What’s more, it could be awfully expensive to replace three-point gearboxes since you may have to take the rotor out to do so, which will bring production to a screeching halt. Luckily, newer devices have a clamping device to combat this potential setback, and you likely can find one to retrofit onto older turbines.
Advantages of Two-Bearing Solutions
Unlike the three-point gearbox, owners of a two-bearing solution do not need to worry about the rotor potentially being removed when exchanging gearboxes, meaning owners will not have to worry about unsolicited interruptions.
The gearbox is surrounded with side supports, and it is attached to the main shaft, which is held by the two rotor bearings. This design could also prevent rotor-bending from entering the gearbox, protecting the gearbox from either detrimental damage or harm that creates costly repairs.
Advantages of Single-Cast Housing
One of the best parts of the single cast housing option is that its structural design prevents misalignment, meaning you won’t have to stop production to perform maintenance and possible costly repairs. Since all of the parts have flange connections, the chances of misalignment are drastically reduced.
This selection is especially popular in medium speed turbines.
How Sentient Science Can Help
By utilizing the Industrial Internet, Sentient Science can help wind farm owners select which model will work best for their needs, and more importantly, help them keep their wind turbines running efficiently to maximize the value of their asset. To learn more, please call 1.888.522.8560.
Source Used:
http://www.windpowermonthly.com/article/1300403/windtech-in-depth-ge-takes-gearbox-support-22mw