Turbines, steam thrust bearings

Steam turbine considerations. The speed at whieh the turbine must operate and the steam eonditions available influenee the operating effieieney of the unit. Double-ended steam turbines require speeial eonsideration of thrust bearing sizing, overspeed proteetion, and governing systems. 

King, T.F., and Capitao, J.W., Impact on Recent Tilting Pad Thrust Bearing Tests on Steam Turbine Design and Performance, Proceedings of the 4th Turbomachinery Symposium, Texas A M University, October 1975, pp. 1-8. 

Other items unique to steam turbines that must be considered are water carryover and fouling. Carryover can leave deposits on the blading, causing loss in performance and increased thrust loads. If carried to an extreme, thrust bearing failure could occur. If a large amount of water is carried over as a slug of liquid, catastrophic failure can occur. 

It is important to seal the glands on the turbine shaft, and a typical arrangement is illustrated in Figure 14-24. Thrust bearing failures can be serious problems for steam turbines and other mechanical drives, as well as the bearings used on the driven equipment. 

BAHR, H.C. Recent improvements in load capacity of large steam turbine thrust bearings, Trans ASME Jrn. of Engr. for Power,, 130-136, Jan. 1961. 

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