摘要 |
A method of positioning a shaft and associated seal in turbomachinery utilizing electromagnetic bearings. The method includes applying electrical power to the electromagnetic bearings' windings, the shaft center being in a first position and the shaft being in contact with the associated seal. Power adjustment to the electromagnetic bearings moves the shaft. Shaft movements can manipulate the seal, the movements being of decreasing amplitude to a position in which the seal is out of contact with the shaft when the shaft is rotated at its centered position during normal operation. The shaft is in its centered position during normal operation when the shaft axis is substantially coaxial with an axis of the electromagnetic bearings. Movements of decreasing amplitude may include oscillations of decreasing amplitude about one or more axes, or may include a spiral rotation with a decreasing radius to move the shaft center from initial to final positions. |