Tests show a manufacturing defect caused the failure of a turbine off the coast of Nantucket, a mishap that has energized opponents of renewable energy.
Now, if I were on their engineering team, I’d probably try a combination of magnetic and roller bearings. Use magnetic bearings to support the weight, while securing everything in place with radial bearings.
That way, the mechanical bearings don’t have to support the weight, magnets can take care of most if not all of that, saving undue wear and tear on the mechanical bearings.
Actually, magnetic bearings experience wear as well.
So called “permanent” magnets gradually lose their charge over time through interactions with opposing magnetic fields, heat, and mechanical stresses. Neodymium, for example, loses about 0.1% of it’s field strength per year even when it isn’t being used for anything. This is why you can’t use magnets to make perpetual motion machines:
Magnets are basically batteries that store energy in the form of a magnetic field, eventually they run out of charge and need to be re-magnetized.
This makes passive magnetic bearings really tricky to design, so most of those in use are active types that also employ sensors and electromagnets to ensure stability. These electronics also degrade over time, so usually a mechanical bearing is a better choice unless the use-case requires a frictionless axle.
Everything degrades over time, that’s a given, nothing lasts forever. But if they relieve the weight from the mechanical bearings with magnets, then they might last quite a bit longer before needing service.
True that, and very well explained I might add.
Now, if I were on their engineering team, I’d probably try a combination of magnetic and roller bearings. Use magnetic bearings to support the weight, while securing everything in place with radial bearings.
That way, the mechanical bearings don’t have to support the weight, magnets can take care of most if not all of that, saving undue wear and tear on the mechanical bearings.
I dunno, just a thought.
Actually, magnetic bearings experience wear as well.
So called “permanent” magnets gradually lose their charge over time through interactions with opposing magnetic fields, heat, and mechanical stresses. Neodymium, for example, loses about 0.1% of it’s field strength per year even when it isn’t being used for anything. This is why you can’t use magnets to make perpetual motion machines:
Magnets are basically batteries that store energy in the form of a magnetic field, eventually they run out of charge and need to be re-magnetized.
This makes passive magnetic bearings really tricky to design, so most of those in use are active types that also employ sensors and electromagnets to ensure stability. These electronics also degrade over time, so usually a mechanical bearing is a better choice unless the use-case requires a frictionless axle.
Everything degrades over time, that’s a given, nothing lasts forever. But if they relieve the weight from the mechanical bearings with magnets, then they might last quite a bit longer before needing service.