Overhung compressors

Whenever a hot-gas expander is employed, the thrust bearing of the compressor train is located in the expander. This coupling arrangement minimizes the coupling overhung mass, thus reducing the risk of undue... 

Clair, M., Application of Magnetic Bearings and Dry Gas Seals to an Overhung Compressor, Revolve Proceedings, April 1992. 

Another common type of compressor is manufactured in an integrally geared configuration. It is basically an overhung style machine mounted on a gear box and uses the gear pinion shaft extension to mount an... 

Figure 5 1. Single-s, verttcally split, overhung style centrifugal compressor. Courtesy of Elliott Companyi...

Figure 5-3. Overhung, gearbox mounted centrifugal compressor. Courtesy of Atlas Copco Comptec fnc.)...

Figure 5-4. Diagram of a single-stage overhung type centrifugal compressor.

Vibration and failure are particularly liable to occur when a small-diameter pipe carries a heavy overhung weight. Within 30 minutes of the start of a new compressor, a pressure gauge fell off for this reason [24]. 

The actual dynamics of centrifugal compressors are determined by their design. Common designs are overhung or cantilever, centerline, and bullgear. 

Overhung rotors present an easier alignment problem because shaft-end alignment is necessary only at the coupling between the compressor and driver. 

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