Integrally geared compressor with an axial compressor unit and method

Abstract

The integrally geared compressor comprises a bull gear supported for rotation in a gear casing, and a plurality of pinion shafts supported for rotation in the gear casing. Each pinion shaft comprises a respective pinion, which meshes with the bull gear. A first pinion shaft has a first end drivingly coupled to an axial compressor unit comprising a gas inlet, a gas outlet and an axial compression wheel. A second pinion shaft is drivingly coupled to a centrifugal compressor arrangement.

1 . An integrally geared compressor, comprising:
 a bull gear supported for rotation in a gear casing; and   a plurality of pinion shafts, supported for rotation in the gear casing; each pinion shaft comprising a respective pinion, which meshes with the bull gear;   wherein a first of said plurality of pinion shafts has a first end drivingly coupled to a first axial compressor unit comprising a gas inlet, a gas outlet and an axial compression wheel, which is supported in an overhung fashion at the first end of the first of said plurality of pinion shafts; wherein a second compressor unit is supported in an over-hung fashion at a second end of the first of said plurality of pinion shafts; wherein the gas outlet of the first axial compressor unit is fluidly coupled to a gas inlet of the sec-ond compressor unit; and wherein a second of said plurality of pinion shafts is drivingly coupled to a centrifugal compressor arrangement comprising a further compres-sor unit supported in an overhung fashion at a first end of the second of said plurality of pinion shafts; the further compressor unit being a centrifugal compressor unit.   
     
     
         2 . The integrally geared compressor of  claim 1 , wherein the gas inlet of the first axial compressor unit is an axial gas inlet and the gas outlet of the first axial compressor unit is a radial gas outlet. 
     
     
         3 . The integrally geared compressor of  claim 2 , wherein the radial gas outlet of the first axial compressor unit comprises a vaned diffuser. 
     
     
         4 . The integrally geared compressor  claim 1 , wherein the first axial compressor unit is a multi-stage axial compressor unit. 
     
     
         5 . The integrally geared compressor of  claim 1 , wherein the second compressor unit is an axial compressor unit. 
     
     
         6 . The integrally geared compressor of  claim 1 , wherein the second compressor unit comprises a first centrifugal compressor stage. 
     
     
         7 . The integrally geared compressor of  claim 6 , wherein a gas outlet of the first centrifugal compressor stage is fluidly coupled to a gas inlet of a second cen-trifugal compressor stage of the further compressor unit. 
     
     
         8 . The integrally geared compressor of  claim 1 , wherein the second of said plurality of pinion shafts has a second end drivingly coupled to a third centrifugal compressor stage supported in an overhung fashion at the second end of the second of said plurality of pinion shafts. 
     
     
         9 . The integrally geared compressor of  claim 7 , wherein a gas inlet of the third centrifugal compressor stage is fluidly coupled to a gas outlet of the second centrifugal compressor stage.