Magnetic bearings provide many advantages for turbomachinery including; lower maintenance, higher efficiency and higher reliability. However, the greatest benefit for turboexpanders is realized by the ability of the magnetic bearings to run in the process gas which in turn eliminates the dry gas seals, lube oil, and the lubrication system. As a result, there is no lube oil to contaminate the process and no possibility for the cryogenic process fluid to infiltrate and solidify the oil.
Elimination of the lubrication system also provides significant space and weight savings for off-shore applications. Turboexpander OEM’s estimate that the weight of the skid can be reduced by more than 30 percent and the overall footprint can be reduced by almost 40 percent by applying magnetic bearings. All the major OEM's equip their turboexpanders with S2M magnetic bearings.