High Pressure, Single Stage Rotor

Patent metadata

Field	Value
Publication number	US-2016208801-A1
Application number	US-201514600997-A
Country	US
Kind code	A1
Filing date	Jan 20, 2015
Priority date	Jan 20, 2015
Publication date	Jul 21, 2016
Grant date	—

Abstract

Rotors for a rotary screw compressor having geometries that increase the efficiency of the compression process. The thermodynamic behavior of the rotors may be improved through an increase in the number of male and female lobes of the rotors and/or by an increased wrap angle, such as, for example, using wrap angles that exceed 360 degrees. By increasing the number of lobes, the rotors may have improved resistance to bending of the rotors that may otherwise occur when the temperature of the rotors is elevated and/or the rotor is utilized in relatively high pressure compression applications. The improved resistance to bending may allow the rotors to retain the relatively small size of the work spaces between intermeshed lobes of the rotors in which captured working fluid is being compressed.

First claim

1 . A rotary screw compressor system comprising:
a male screw rotor having a male helical screw portion, the male helical screw portion having a plurality of male lobes, the plurality of male lobes being between four to eight males lobes, inclusive, and a male rotor wrap angle between approximately 350 degrees to 450 degrees, inclusive; and a female screw rotor having a female helical screw portion configured to intermesh with the male helical screw portion, the female helical screw portion having a plurality of female lobes and a female rotor wrap angle.

2 . The rotary screw compressor system of claim 1 , wherein the female rotor wrap angle is between approximately 250 degrees and approximately 325 degrees, inclusive.

3 . The rotary screw compressor system of claim 1 , wherein the number of female lobes of the plurality of female lobes is greater than the total number of male lobes of the plurality of male lobes by one or two female lobes.

4 . The rotary screw compressor system of claim 1 , wherein the plurality of male lobes comprises at least five male lobes.

5 . The rotary screw compressor system of claim 1 , wherein the plurality of female lobes comprises between five to ten female lobes, inclusive.

6 . The rotary screw compressor system of claim 5 , wherein the male helical screw rotor and female helical screw rotor are configured to intermesh to compress a working fluid to approximately 11 bar absolute.

7 . The single stage, direct cooled rotary screw compressor system of claim 1 , wherein the male helical screw rotor and female helical screw rotor are configured to intermesh to compress a working fluid to approximately 11 bar absolute.

8 . A single stage, direct cooled rotary screw compressor system comprising:
a male screw rotor having a male helical screw portion, the male helical screw portion having at least four male lobes and a male rotor wrap angle, the male rotor wrap angle being between approximately 350 degrees and 450 degrees, inclusive; and a female screw rotor having a female helical screw portion configured to intermesh with the male helical screw portion, the female helical screw portion having a plurality of female lobes and a female wrap angle between approximately 250 degrees and approximately 325 degrees, inclusive.

9 . The single stage, direct cooled rotary screw compressor system of claim 8 , wherein the number of female lobes of the plurality of female lobes is greater than the total number of male lobes of the plurality of male lobes by one or two female lobes.

10 . The single stage, direct cooled rotary screw compressor system of claim 9 , wherein the female rotor wrap angle is at least 360 degrees.

11 . The single stage, direct cooled rotary screw compressor system of claim 8 , wherein the male helical screw rotor and female helical screw rotor are configured to intermesh to compress a working fluid to approximately 11 bar absolute.

12 . The single stage, directed cooled rotary screw compressor system of claim 11 , wherein the male rotor wrap angle is between approximately 420 degrees and 450 degrees, inclusive.

13 . A rotary screw compressor system for compressing a working fluid, the rotary screw compressor system comprising:
a compression chamber; a male screw rotor having a male helical screw portion, the male helical screw portion having a plurality of male lobes and a male rotor wrap angle; a female screw rotor having a female helical screw portion configured to intermesh with the male helical screw portion within the compression chamber to compress the working fluid to a discharge pressure, the female helical screw portion having a female rotor wrap angle and a plurality of female lobes, at least one of the male rotor wrap angle and the female rotor wrap angle being between approximately 250 degrees and 325 degrees; and a coolant system configured to circulate a coolant to the compression chamber to cool a temperature of at least a portion of the working fluid that is being compressed in the compression chamber.

14 . The rotary screw compressor system of claim 13 , wherein only the male rotor wrap angle is between approximately 350 degrees and 450 degrees.

15 . The rotary screw compressor system of claim 13 , wherein the male rotor wrap angle is between approximately 420 degrees and 450 degrees.

16 . The rotary screw compressor system of claim 13 , wherein the number of female lobes of the plurality of female lobes is greater than the total number of male lobes of the plurality of male lobes by one or two female lobes.

17 . The rotary screw compressor system of claim 16 , wherein a ratio of the plurality of male lobes to the plurality of female lobes is 5:7.

18 . The rotary screw compressor system of claim 13 , wherein the plurality of female lobes is between five and ten female lobes, inclusive and the plurality of male lobes is between four and eight male lobes, inclusive.

19 . The rotary screw compressor system of claim 18 , wherein the discharge pressure is approximately 11 bar absolute.

20 . The rotary screw compressor system of claim 13 , wherein the discharge pressure is approximately 11 bar absolute.

Assignees

• Ingersoll Rand Co

Inventors

• Hauser Jan
• Beinert Michael
• Huettermann Dieter

Classifications

• F04C18/16 Primary

  with helical teeth, e.g. chevron-shaped, screw type {(for non-parallel axes of movement F04C18/48)} · CPC title

• F04C29/04

  Heating; Cooling (of machines or engines in general F01P); Heat insulation (heat insulation in general F16L59/00) · CPC title

• F04C18/084

  Toothed wheels · CPC title