Centrifugal compressors bearings

The active magnetic bearing s versatility allows it to be used in almost any rotating machine. Examples include compressors, blowers, pumps, turbines, centrifuges, x-ray tubes, vacuum pumps, spindles for... 

The centrifugal compressor is composed of a casing containing a rotating element, rotor, which is supported by a set of bearings. For most multistage compressors, shaft end seals are located in-board of the bearings. 

Centrifugal compressor impellers, with the exception of the open impeller, are thrust unbalanced. The machine also has a requirement for a location device to maintain axial clearances. For these reasons, all centrifugal compressors use some form of thrust bearing. 

The bearings used in axial compressors are the same journal and thrust type used in the centrifugal compressor. Refer to Chapter 5 for a complete description of these bearings. 

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Figure 76. Liquid film shaft seal with nlindrkwl hushing lor a high-pressure centrifugal compressor a) Shaft b) Bearing c) Pressure side d) Ambient side e) Floating seal rings f) Sea) oil surge vessel g) Sea) oil h) Lube oil i) Drain to gas-oil separaior k) Drain lo lube oil tank l) Elevation for seal oil head...

Because magnetic bearings do not require lubrication, they are particularly suited to applications such as canned pumps, vacuum pumps, turbo-expanders, and some centrifuges. As of 1994, some centrifugal compressors in the 5000-kW power range had been equipped with magnetic bearings. 

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