Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
  • F04D29/00—Details, component parts, or accessories
  • F04D29/40—Casings; Connections of working fluid
  • F04D29/42—Casings; Connections of working fluid for radial or helico-centrifugal pumps
  • F04D29/44—Fluid-guiding means, e.g. diffusers
  • F04D29/46—Fluid-guiding means, e.g. diffusers adjustable
  • F04D29/462—Fluid-guiding means, e.g. diffusers adjustable especially adapted for elastic fluid pumps
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
  • F04D29/00—Details, component parts, or accessories
  • F04D29/40—Casings; Connections of working fluid
  • F04D29/42—Casings; Connections of working fluid for radial or helico-centrifugal pumps
  • F04D29/4206—Casings; Connections of working fluid for radial or helico-centrifugal pumps especially adapted for elastic fluid pumps
  • F04D29/4213—Casings; Connections of working fluid for radial or helico-centrifugal pumps especially adapted for elastic fluid pumps suction ports
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2250/00—Geometry
  • F05D2250/50—Inlet or outlet
  • F05D2250/51—Inlet

Definitions

• the present invention relates to the field of compressors and, more particularly, to an apparatus for the adjustment of inlet guide vanes to the compressor.
• Centrifugal compressors are commonly used in the liquefied natural gas industry. This application requires a large range of compressor performance characteristics due to the nature of the liquification process. In order to achieve all the variations of performance needed, it is common industry practice to use a compressor that is able to vary the angle of its vanes near the inlet stage. The ability to change the angle of the inlet vanes for various processes allows a user to achieve a broader range of performance characteristics.
• United States Patent No. 6,679,057 (the '057 patent) to Arnold discloses a turbocharger guide vane arrangement including a plurality of vanes coupled to a unison ring.
• the unison ring is rotated by rotation of an actuator crank, which causes an actuating lever arm to move around a longitudinal axis of the actuator crank, which in turn effects rotation of the unison ring via an actuating pin.
• the actuating mechanism in the '057 patent is shown in further detail in United States Patent No. 6,269,642 to Arnold et al.
• crank arm of the prior art is not coupled to any of the guide vanes, especially in the context of a rack and pinion gear driven master vane. Accordingly, the mechanisms for moving vanes may be improved upon.
• the present invention is directed to an apparatus for adjustment of inlet guide vanes of a compressor.
• the apparatus includes a ring having a plurality of slots spaced around a circumference thereof; a plurality of lever arm assemblies each having a pin that includes a body with a first end and a second end and a lever arm extending perpendicularly from the second end of the body of the pin; a plurality of vanes each coupled to an end of one of the plurality of lever arms by a shaft; and a rack and pinion drive mechanism.
• the pin of each of the lever arm assemblies is configured to be positioned within each of the plurality of slots such that the first end of the pin extends into the slot.
• the rack and pinion drive mechanism includes a pinion coupled to the shaft of one of the plurality of vanes, thereby creating a drive vane; and a driven rack operationally coupled to the pinion.
• the drive vane is configured to rotate the ring via the rack and pinion drive mechanism, thereby adjusting an angular position of the plurality of vanes.
• the driven rack may be coupled to a drive shaft that is powered by a hydraulic cylinder located externally from the compressor.
• the apparatus may be positioned such that it is isolated from a flow path of the compressor by an endwall cover plate.
• the ring may be constrained axially in the compressor by an end wall and the end wall cover plate.
• the plurality of vanes may be each rotated to the same angle when the drive vane rotates the ring via the rack and pinion drive mechanism, thereby adjusting the angular position of the plurality of vanes.
• the present invention is also directed to a compressor including a casing; a rotor having a shaft and an impeller positioned within the casing; and a vane adjustment mechanism positioned within the casing and surrounding the rotor.
• the vane adjustment mechanism includes a ring having a plurality of slots spaced around a circumference thereof; a plurality of lever arm assemblies each having a pin that includes a body with a first end and a second end and a lever arm extending perpendicularly from the second end of the body of the pin; a plurality of vanes each coupled to an end of one of the plurality of lever arms by a shaft; and a rack and pinion drive mechanism.
• the pin of each of the lever arm assemblies is configured to be positioned within each of the plurality of slots such that the first end of the pin extends into the slot.
• the rack and pinion drive mechanism includes a pinion coupled to the shaft of one of the plurality of vanes, thereby creating a drive vane; and a driven rack operationally coupled to the pinion.
• the drive vane is configured to rotate the ring via the rack and pinion drive mechanism, thereby adjusting an angular position of the plurality of vanes.
• the driven rack may be coupled to a drive shaft that is powered by a hydraulic cylinder located externally from the compressor.
• the apparatus may be positioned such that it is isolated from a flow path of the compressor by an endwall cover plate.
• the ring may be constrained axially in the compressor by an end wall and the end wall cover plate.
• the plurality of vanes may be each rotated to the same angle when the drive vane rotates the ring via the rack and pinion drive mechanism, thereby adjusting the angular position of the plurality of vanes.
• the present invention is directed to a vane adjustment mechanism for a compressor.
• the vane adjustment mechanism includes a ring; and a plurality of vanes pivotally attached around a circumference of the ring.
• One of the plurality of vanes is a drive vane configured to rotate the ring via a rack and pinion drive mechanism, thereby adjusting an angular position of the plurality of vanes.
• the ring may include a plurality of slots spaced around a circumference thereof.
• the vane adjustment mechanism may further include a plurality of lever arm assemblies each including a pin having a body with a first end and a second end and a lever arm extending perpendicularly from the second end of the body of the pin.
• the pin of each of the lever arm assemblies may be configured to be positioned within each of the plurality of slots such that the first end of the pin extends into the slot.
• the plurality of vanes may be each coupled to an end of one of the plurality of lever arms by a shaft.
• the rack and pinion drive mechanism may include a pinion coupled to the shaft of one of the plurality of vanes, thereby creating a drive vane; and a driven rack operationally coupled to the pinion.
• the driven rack may be coupled to a drive shaft and a hydraulic cylinder may be provided to power the drive shaft to drive the driven rack.
• FIG. 1 is a cutaway perspective view of an apparatus for adjusting an angular position of a plurality of inlet guide vanes situated within a compressor in accordance with the present invention
• FIG. 2 is a perspective view of the apparatus for adjusting the angular position of a plurality of inlet guide vanes for a compressor, in accordance with the present invention
• FIG. 3 is a front plan view of the apparatus shown, in FIG. 2;
• FIG. 4 is a cross-sectional view of the apparatus taken along lines 4-4 of FIG. 3;
• FIG. 5 is a perspective view of a rotating ring of the apparatus
• FIG. 6 is a perspective view of a vane with a lever arm of the apparatus
• FIG. 7 is a perspective view of a plurality of vanes secured within the ring via the corresponding lever arms thereof;
• FIG. 8 is a partial front plan view of the ring with a rack and pinion mechanism of the apparatus
• FIG. 9 is a partial rear plan view of the ring with the rack and pinion mechanism of the apparatus.
• FIG. 10 is a front perspective view of the apparatus showing the rack
• FIG. 11 is a rear perspective view of the apparatus showing the rack and pinion mechanism.
• FIG. 12 is a perspective view of the apparatus showing the ring centered on an endwall.
• a centrifugal compressor denoted generally as reference numeral 1
• the rotor includes an impeller 5 and a shaft 7.
• An apparatus, or vane adjustment mechanism, denoted generally as reference numeral 9, for adjusting an angular position of a plurality of inlet guide vanes 11 is positioned within casing 3 and surrounds shaft 7 of the rotor.
• Compressor 1 further includes a bearing housing 29 coupled to endwall 17.
• Vane adjustment mechanism 9 includes a rotating ring 13 with the plurality of inlet guide vanes 11 positioned around a circumference thereof as will be described in greater detail hereinafter. Vane adjustment mechanism 9 is positioned within casing 3 of compressor 1, such that it is isolated from a flow path of compressor 1 by an endwall cover plate 15. By keeping the vane rotation mechanism 9 out of the flow path, aerodynamic efficiency and performance of the inlet stage may be maintained. Additionally, rotating ring 13 constrained axially in compressor 1 by an endwall 17 and endwall cover plate 15. Rotating ring 13 should also be aligned with the centerlme of compressor 1 to ensure that vanes 11 rotate at the same angle. This is achieved by centering rotating ring 13 on a surface of endwall 17, as shown in FIG. 12, for instance.
• Vane adjustment mechanism 9 also includes a rack and pinion drive mechanism 21 as will be discussed in greater detail hereinafter.
• Rack and pinion drive mechanism 21 is coupled to a drive shaft 23 that is powered by a hydraulic cylinder 25 located in a housing 27 positioned externally from compressor 1.
• vane adjustment mechanism 9 includes a plurality of adjustable inlet guide vanes 11 positioned around the circumference of rotating ring 13. While vane adjustment mechanism 9 illustrated in the figures includes sixteen adjustable inlet guide vanes 11, this is not to be construed as limiting the present invention as any suitable number of vanes may be utilized. Generally, in order for the aerodynamic design of the adjustable inlet guide vanes 11 to be effective, each vane 11 in the inlet section of compressor 1 should be rotated at the same angle. As shown in FIG. 5, vane adjustment mechanism 9 achieves the aforementioned design criteria by using a rotating ring 13 that can accommodate each vane 11 within an elongated slot 31 thereof via a lever arm assembly 33.
• each lever arm assembly 33 includes a pin 35 having a body 37 with a first end 39 and a second end 41 and a lever arm 43 extending perpendicularly from second end 41 of body 37 of pin 35. Vanes 11 are each coupled to an end of one of the plurality of lever arms 43 by a shaft 45. Body 37 of pin 35 of each lever arm assembly 33 is configured to be positioned within elongated slots 31 of rotating ring 13, such that first end 39 of pin 35 extends into elongated slot 31. As rotating ring 13 rotates, each vane 11 is rotated by the same angle. [0032] With reference to FIGS. 7 through 12, and with continuing reference to FIGS.
• vane adjustment mechanism 9 also includes a rack and pinion drive mechanism 21 configured to drive one of the plurality of vanes 11, thereby creating a drive vane 47.
• Rack and pinion drive mechanism 9 includes a pinion 53 coupled to an elongated shaft 55 (see FIG. 4) of drive vane 47 and a driven rack 57.
• Driven rack 57 includes a plurality of teeth 59 that are configured to engage a plurality of teeth 61 on the pinion 53, thereby operationally coupling driven rack 57 to pinion 53.
• An end of driven rack 57 is coupled to drive shaft 23 that is powered by hydraulic cylinder 25.
• Hydraulic cylinder 25 is positioned in a housing 27 positioned externally from the casing 3 of compressor 1 to keep the hydraulic cylinder 25 at a higher temperature than compressor L
• Drive shaft 23 imparts linear motion to driven rack 57 which is converted to rotational motion in pinion 53.
• Drive shaft 23 is coupled to driven rack 57 through a hole 63 provided in endwall cover plate 15.
• drive shaft 23 imparts linear motion to driven rack 57.
• This linear motion is converted to rotational motion in pinion 53, thereby rotating drive vane 47.
• Drive vane 47 transfers torque to rotating ring 13 due to the positioning of pin 35 of lever arm assembly 33 within elongated slot 31 of rotating ring 13.
• the torque is thereby transmitted to the remaining vanes 11 as shown in FIGS. 8 and 9. More specifically, as drive vane 47 rotates, pin 35 of lever arm assembly 33 moves within elongated slot 31 of rotating ring 13, thereby causing pins 35 of lever arm assemblies 33 of the other vanes 11 to move within their respective slots of rotating ring 13.
• drive vane 47 is configured to rotate rotating ring 13 via rack and pinion drive mechanism 21 to adjust the angular position of the plurality of vanes 11.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Structures Of Non-Positive Displacement Pumps (AREA)

Applications Claiming Priority (2)

Publications (1)

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ID=39831410

Family Applications (1)

Country Status (5)

Families Citing this family (49)

Family Cites Families (72)

• 2008
  • 2008-04-09 EP EP08745366A patent/EP2165047A1/en not_active Withdrawn
  • 2008-04-09 JP JP2010503175A patent/JP2010523898A/ja active Pending
  • 2008-04-09 CN CN200880011398A patent/CN101743379A/zh active Pending
  • 2008-04-09 WO PCT/US2008/059736 patent/WO2008124758A1/en not_active Ceased
  • 2008-04-09 US US12/532,435 patent/US20100172745A1/en not_active Abandoned

Non-Patent Citations (1)

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