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Chapter 3





             Centrifugal Compressors




                                        †
                                                    ‡
             Jason Wilkes*, Brian Pettinato , Rainer Kurz , Justin Hollingsworth*,
                                                                          ¶
                                      §
                           ‡
             Donghui Zhang , Matt Taher , Chris Kulhanek*, Ferdinand Werdecker ,
             Dirk B€ uche and George Talabisco #
                       k
             *                                        †
              Southwest Research Institute, San Antonio, TX, United States, Elliott Group, Jeannette, PA,
                                                         §
                      ‡
             United States, Solar Turbines, Inc., San Diego, CA, United States, Bechtel, San Francisco, CA,
                      ¶
                                                    k
             United States, EagleBurgman, Houston, TX, United States, MAN Diesel & Turbo Schweiz AG,
                          #
             Z€ urich, Switzerland, Dresser-Rand, Olean, NY, United States
             Basics of Inline Centrifugal Compressors
             Inline centrifugal compressors can be described as a combination of one or more
             centrifugal compressor stages operating about a common axis. Each stage is
             comprised of rotating impellers that impart kinetic energy into the gas that is
             then converted to a rise in static pressure as the gas decelerates. For the remain-
             der of this chapter, it can be assumed that all of the impellers are operating on
             the same shaft.
                The different working principles cause differences in the operating charac-
             teristics of the centrifugal compressors compared to those of the reciprocating
             unit. Centrifugal compressors are used in a wide variety of applications in
             chemical plants, refineries, onshore and offshore gas lift and gas injection appli-
             cations, gas gathering, and in the transmission and storage of natural gas. Cen-
             trifugal compressors have been used for outlet pressures as high as 70MPa, thus
             overlapping with reciprocating compressors over a portion of the flow-rate/
             pressure domain. Centrifugal compressors are usually either gas turbine or elec-
             tric motor driven, although in downstream applications, steam turbines or tur-
             boexpanders may be used. Typical operating speeds for centrifugal compressors
             in gas transmission applications are about 14,000rpm for 3700kWunits and
             8000rpm for 15,000kWunits.

             General Requirements for Range, Pressure Ratio, and Performance
             for Inline Centrifugal Compressors in Various Applications?
             The requirements for Range, Pressure ratio, and Performance vary greatly
             between applications. While pipeline compressors typically operate at low pres-
             sure ratios (say, from 1.1 to 1.7), other applications may require significantly


             Compression Machinery for Oil and Gas. https://doi.org/10.1016/B978-0-12-814683-5.00003-1
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