Method and system for cooling a motor-compressor with a closed-loop cooling circuit

Patent metadata

Field	Value
Publication number	US-10030672-B2
Application number	US-201514863679-A
Country	US
Kind code	B2
Filing date	Sep 24, 2015
Priority date	Oct 27, 2010
Publication date	Jul 24, 2018
Grant date	Jul 24, 2018

Abstract

A fluid compression system is disclosed having a hermetically-sealed housing with at least a motor and a compressor arranged therein. The motor may drive both the compressor and a blower device coupled to the housing or otherwise arranged within the housing and configured to circulate a cooling gas throughout the housing and thereby cool the motor and accompanying radial bearings. The blower device circulates the cooling gas through a closed-loop circuit which may include a heat exchanger and gas conditioning skid. Buffer seals may be used to seal the shaft on both sides of the compressor so as to prevent the migration of liquid and solid contaminants into the closed-loop cooling circuit.

First claim

We claim:

1. A fluid compression system comprising:
a hermetically-sealed housing comprising a motor end and a compressor end, the housing defining a plurality of internal cooling passages;
a motor disposed within the housing and coupled with a rotatable shaft, the motor being in fluid communication with the plurality of internal cooling passages;
a compressor disposed within the housing, the compressor being axially-spaced from the motor and coupled with the rotatable shaft;
radial bearings disposed at each end of the rotatable shaft and in fluid communication with the plurality of internal cooling passages;
one or more buffer seals arranged about the rotatable shaft on either side of the compressor and inboard from the radial bearings, each buffer seal being configured to prevent leakage of a process gas into the plurality of internal cooling passages; and
an impeller axially spaced from the compressor and coupled with a free end of the rotatable shaft, the impeller being configured to circulate a cooling gas in a closed cooling loop through the plurality of internal cooling passages; and
an external gas conditioning skid fluidly coupled with and disposed downstream from the impeller, the external gas conditioning skid being configured to receive the cooling gas from the impeller and direct at least a portion of the cooling gas to the one or more buffer seals.

2. The fluid compression system of claim 1 , wherein the impeller is disposed adjacent the motor end of the housing.

3. The fluid compression system of claim 2 , further comprising a blower casing bolted directly to the motor end of the housing.

4. The fluid compression system of claim 2 , further comprising an integrated separator axially-spaced from the compressor and coupled with the rotatable shaft.

5. A fluid compression system, comprising:
a hermetically-sealed housing comprising a motor end and a compressor end, the housing defining a plurality of internal cooling passages;
a rotatable shaft comprising a motor rotor section, a first driven section, and a second driven section, the rotatable shaft extending between the motor end and the compressor end of the housing;
a motor disposed within the housing and in fluid communication with at least one of the plurality of internal cooling passages, the motor being coupled with the rotatable shaft and forming part of the motor rotor section of the rotatable shaft that drives the first and second driven sections;
a first compressor disposed in the housing and axially-spaced from the motor, the first compressor forming part of the first driven section of the rotatable shaft;
radial bearings disposed proximal each end of the motor rotor and first and second driven sections of the rotatable shaft, the radial bearings being in fluid communication with at least one of the plurality of internal cooling passages;
one or more buffer seals disposed about the rotatable shaft on either side of the first compressor and inboard from the radial bearings, each buffer seal being configured to prevent leakage of a process gas into the plurality of internal cooling passages;
a first blower axially-spaced from the first compressor and coupled with a free first end of the rotatable shaft adjacent the compressor end of the housing, the first blower configured to be driven by the motor rotor section of the rotatable shaft to circulate a cooling gas through the plurality of internal cooling passages and regulate a temperature of the motor and the radial bearings; and
an external gas conditioning skid fluidly coupled with and disposed downstream from the first blower, the external gas conditioning skid configured to receive the cooling gas from the first blower and direct at least a portion of the cooling gas to the one or more buffer seals.

6. The fluid compression system of claim 5 , wherein the first blower comprises a centrifugal impeller or an axial fan.

7. The fluid compression system of claim 5 , further comprising an integrated separator axially-spaced from the compressor and coupled with the rotatable shaft.

8. The fluid compression system of claim 5 , further comprising a coupling configured to couple the motor rotor section and the first driven section with one another.

9. The fluid compression system of claim 5 , further comprising a heat exchanger fluidly coupled with and disposed downstream from the first blower, the heat exchanger being configured to reduce the temperature of the cooling gas from the first blower.

10. The fluid compression system of claim 5 , wherein a first end of the motor is coupled with the first driven section and a second end of the motor is coupled with the second driven section.

11. The fluid compression system of claim 10 , further comprising a second compressor disposed in the housing and axially-spaced from the motor, the second compressor being coupled with the second driven section of the rotatable shaft.

12. The fluid compression system of claim 11 , further comprising a second blower coupled with a second free end of the rotatable shaft and configured to be driven by the motor rotor section.

13. A method of cooling a compression system, comprising:
supporting a motor rotor section and a driven section of a shaft within a hermetically-sealed housing with radial bearings, the radial bearings being disposed at each end of the motor rotor and driven sections, and the housing defining a plurality of internal cooling passages;
rotating the motor rotor section;
driving the driven section of the shaft with the motor rotor section;
driving a blower with the motor rotor section, the blower being axially-spaced from a compressor and coupled with a free end of the driven section;
circulating a cooling gas through the plurality of internal cooling passages with the blower;
sealing each end of the driven section of the shaft with buffer seals, the buffer seals being disposed inboard of the radial bearings;
directing the cooling gas from the blower to an external gas conditioning skid fluidly coupled with the blower;
directing at least a portion of the cooling gas from the external gas conditioning skid to the buffer seals;
cooling a motor and the radial bearings with the cooling gas; and
directing the cooling gas to the blower in a closed-loop circuit.

14. The method of claim 13 , wherein the blower comprises a centrifugal impeller.

15. The method of claim 13 , wherein the blower comprises an axial fan.

16. The method of claim 13 , further comprising directing the cooling gas through a heat exchanger to reduce the temperature of the cooling gas.

17. The method of claim 13 , further comprising filtering the cooling gas with a gas conditioning skid.

Assignees

• Dresser Rand Co

Inventors

• Gilarranz Jose L
• Peer David J
• Lombardi Louis
• Rockwood Steven
• Maier William C

Classifications

• F04D29/5806

  Cooling the drive system · CPC title

• F04D29/104

  the sealing fluid being other than the working fluid or being the working fluid treated · CPC title

• F04D25/0686

  specially adapted for submerged use · CPC title

• F04D29/584 Primary

  cooling or heating the machine (F04D29/5846, F04D29/5853 take precedence) · CPC title

• F04D25/0606 Primary

  the electric motor being specially adapted for integration in the pump · CPC title