US20150118018A1 - Compressor, seal gas delivery, and method - Google Patents

Compressor, seal gas delivery, and method Download PDF

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Publication number
US20150118018A1
US20150118018A1 US14/397,023 US201314397023A US2015118018A1 US 20150118018 A1 US20150118018 A1 US 20150118018A1 US 201314397023 A US201314397023 A US 201314397023A US 2015118018 A1 US2015118018 A1 US 2015118018A1
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US
United States
Prior art keywords
seal gas
seal
rotor shaft
holes
delivery system
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US14/397,023
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English (en)
Inventor
Leonardo Baldassarre
Andrea Bernocchi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nuovo Pignone SRL
Original Assignee
Nuovo Pignone SRL
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Nuovo Pignone SRL filed Critical Nuovo Pignone SRL
Assigned to NUOVO PIGNONE SRL reassignment NUOVO PIGNONE SRL ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: BALDASSARRE, LEONARDO, BERNOCCHI, ANDREA
Publication of US20150118018A1 publication Critical patent/US20150118018A1/en
Abandoned legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16J—PISTONS; CYLINDERS; SEALINGS
    • F16J15/00—Sealings
    • F16J15/16—Sealings between relatively-moving surfaces
    • F16J15/34—Sealings between relatively-moving surfaces with slip-ring pressed against a more or less radial face on one member
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D11/00—Preventing or minimising internal leakage of working-fluid, e.g. between stages
    • F01D11/02—Preventing or minimising internal leakage of working-fluid, e.g. between stages by non-contact sealings, e.g. of labyrinth type
    • F01D11/04—Preventing or minimising internal leakage of working-fluid, e.g. between stages by non-contact sealings, e.g. of labyrinth type using sealing fluid, e.g. steam
    • 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
    • F04D29/08—Sealings
    • F04D29/10—Shaft sealings
    • F04D29/12—Shaft sealings using sealing-rings
    • F04D29/122—Shaft sealings using sealing-rings especially adapted for elastic fluid pumps
    • F04D29/124—Shaft sealings using sealing-rings especially adapted for elastic fluid pumps with special means for adducting cooling or sealing fluid
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16J—PISTONS; CYLINDERS; SEALINGS
    • F16J15/00—Sealings
    • F16J15/16—Sealings between relatively-moving surfaces
    • F16J15/34—Sealings between relatively-moving surfaces with slip-ring pressed against a more or less radial face on one member
    • F16J15/3464—Mounting of the seal
    • F16J15/348—Pre-assembled seals, e.g. cartridge seals
    • F16J15/3484—Tandem seals
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16J—PISTONS; CYLINDERS; SEALINGS
    • F16J15/00—Sealings
    • F16J15/16—Sealings between relatively-moving surfaces
    • F16J15/40—Sealings between relatively-moving surfaces by means of fluid

Definitions

  • Embodiments of the subject matter disclosed herein generally relate to turbo machines, and more particularly, to the delivery of seal gas into a compressor end seal.
  • a compressor is a machine which accelerates the particles of a process fluid to, ultimately, increase the pressure of the process fluid, e.g., a gas, through the use of mechanical energy.
  • Compressors are commonly used in the energy industry to produce, process, re-inject and transport many different types of gases.
  • centrifugal compressors in which mechanical energy operates on process fluid input to the compressor by way of centrifugal acceleration, e.g., by rotating a centrifugal impeller by which the process fluid is passing.
  • centrifugal compressors can be said to be part of a class of machinery known as “turbo machines” or “turbo rotating machines”.
  • a compressor 10 may include a rotor shaft 20 rotatably disposed relative to a stator 12 .
  • a shaft end seal in the form of a dry gas seal, indicated generally as 14 in FIG. 1 may be disposed between the rotor shaft 20 and the stator 12 .
  • Dry gas seal 14 may include primary and secondary seal rotor rings 26 and primary and secondary seal stator rings 28 each biased towards a respective one of the primary and secondary seal rotor rings 26 .
  • grooves (not shown) in the dry gas rotor seal rings 26 and stator seal rings 28 may generate a fluid dynamic force to create a running gap which provides a sealing function without contact between the sealing rings.
  • a seal gas typically, filtered process gas, may be supplied to the dry gas seal to support the running gap and otherwise improve the performance of compressor 10 . As shown in FIGS. 1 and 2 , the seal gas may be delivered through an opening 30 in the stator 12 .
  • seal gas may additionally be heated by a dedicated device, such as a heater or heat exchanger to aid in the prevention or suppression of condensation which may arise during or before the expansion of the seal gas within the dry gas seal.
  • a dedicated device such as a heater or heat exchanger to aid in the prevention or suppression of condensation which may arise during or before the expansion of the seal gas within the dry gas seal.
  • seal gas entering the dry gas seal through port 30 may have a high temperature relative to, for example, ambient air and/or gas already present within dry gas seal 14 .
  • this hot seal gas may continue to be supplied to the dry gas seal. Moreover, the temperature of the seal gas may be further increased during a temporary compressor shutdown due to the absorption of residual heat, for example, from stationary compressor components.
  • Heat within the seal gas continuously supplied to the compressor during temporary shutdown may cause a region or regions on the shaft 20 proximate to the dry gas seal 14 to become unevenly heated, i.e., one or more regions of the rotor shaft 20 may develop a temperature differential with respect to neighboring regions of the rotor shaft 20 .
  • These so-called hotspots are potentially problematic.
  • seal gas entering the dry gas seal through port 30 may impinge against a dry gas seal component adjacent the compressor rotor shaft, or worse, directly against a surface of the rotor shaft itself.
  • one or more such hotspots may cause a deformation, e.g., bending, warping, etc., in the rotor shaft.
  • a vibration in the rotating assembly may be induced as a consequence of the deformation.
  • the vibration may have a magnitude sufficient to render the compressor vulnerable to damage, particularly when the compressor approaches its first critical speed.
  • Such vibration may necessitate one or more additional temporary shutdowns and restarts to allow for the uneven heating of the rotating assembly to dissipate and for the deformation to ameliorate. In severe cases or in the event of vibration related damage to the compressor, a full shutdown may be required.
  • a compressor and more particularly, a seal gas delivery system, which evenly distributes seal gas heat within an end seal, which allows a compressor to be more easily restarted after temporary shutdown, which prevents a localized impingement of hot seal gas against a rotor shaft of the compressor, which prevents thermal deformation of the rotor shaft, which provides an easy retrofit solution, which is low in cost, which maintains the existing, weight, configuration, and manner of operation of a compressor and dry gas seal and which provides an alternative to heat distribution effected by compressor shaft rotation.
  • a seal gas delivery system for an end seal on a turbo machine rotor shaft includes a seal gas passageway for delivering a seal gas to the end seal and a seal gas distributor for receiving at least a portion of the seal gas from the seal gas passageway, the seal gas distributor having a plurality of holes for distributing the seal gas about the rotor shaft during turbo machine standstill, the holes being located on a cylindrical surface; in this way, a swirl is induced in the seal gas around the shaft by the distributor.
  • the holes are, in an embodiment, arranged circularly.
  • the holes are, in an embodiment, arranged all around said rotor shaft, and, in an embodiment, regularly all around said rotor shaft.
  • a turbo machine includes a stator, a rotor shaft rotatable relative to the stator, an end seal disposed between the stator and the rotor, a seal gas passageway for delivering a seal gas to the end seal, and a seal gas distributor for receiving at least a portion of the seal gas from the seal gas passageway and distributing the seal gas about the rotor shaft; the seal gas distributor has a plurality of holes and its holes are located on a cylindrical surface; in this way, during turbo machine standstill to induce a swirl in the seal gas around the shaft based on an orientation of the holes in the seal.
  • a container is provided for containing the seal gas; container is fluidly connected to the seal gas distributor.
  • a method of operating a turbo machine including an end seal on a rotor shaft thereof can include the steps of delivering a seal gas to the end seal during turbo machine standstill and distributing the seal gas about the rotor shaft through a plurality of holes arranged all around said rotor shaft to prevent uneven heating of the rotor shaft.
  • the seal gas flow ejected from at least some, preferably all, of the holes is inclined with respect to a corresponding radial direction defined in relation to a longitudinal axis of the rotor shaft.
  • FIG. 1 is a partial-cross sectional view of a compressor.
  • FIG. 2 is a partial cut away view of the compressor shown in FIG. 1 .
  • FIG. 3 is a partial cross-sectional view of a compressor according to an exemplary embodiment.
  • FIG. 4 is a partial perspective view of a distributor of the compressor shown in FIG. 3 .
  • FIG. 5 is a partial cross-sectional view of a compressor according to another exemplary embodiment.
  • FIG. 6 is a partial perspective view of a distributor of the compressor shown in FIG. 5 .
  • FIG. 7 depicts a method according to an exemplary embodiment.
  • FIGS. 3 and 4 show an exemplary embodiment of a seal gas delivery system according to the present invention.
  • a compressor 110 includes a stator 112 having a seal gas passageway 122 extending through stator 112 to a dry gas seal 114 .
  • Seal gas may be delivered through a primary port 154 in stator 112 to dry gas seal 114 .
  • Compressor 110 further includes a labyrinth seal 158 adjacent dry gas seal 114 .
  • labyrinth seal 158 is provided with a distributor 140 in the form of a ring portion extending from labyrinth seal 158 .
  • Distributor 140 is provided with a plurality of gas injection holes 160 ; holes 160 are located on a cylindrical surface, in particular, they are arranged circularly according to one circle.
  • seal gas may continue to be supplied to dry gas seal 114 , as previously discussed. At least a portion of the seal gas may be received by distributor 140 and released about the circumference of rotor shaft 120 through each of the plurality of seal gas injection holes 160 . This action may enhance a homogenous distribution of seal gas around the shaft, with or without swirl motion, and thereby inhibit localized heating of rotor shaft 120 .
  • distributor 140 may also prevent seal gas exiting port 154 from impinging directly against rotor shaft 120 .
  • labyrinth seal 158 and dry gas seal 114 define a chamber 156 in which the surface of turbo shaft 120 is exposed directly to seal gas. Since distributor 140 is disposed between rotor shaft 120 and vent 130 , direct impingement of potentially hot seal gas against this surface is inhibited or prevented.
  • gas injection holes 160 may also be configured to provide a circumferential swirl of seal gas within chamber 156 to further promote the circulation of gas and the uniform distribution of heat about shaft 120 .
  • each gas injection hole 160 may define an axis 164 at an angle 168 with a radial line 166 extending from a longitudinal axis of rotor shaft 120 through the center of the gas injection hole 160 ; in other words, the seal gas flow ejected from holes 160 is inclined with respect to a corresponding radial direction defined in relation to a longitudinal axis of said rotor shaft.
  • angle 168 may vary between holes 160 of distributor 140 in order to, for example, induce a greater degree of turbulence providing a uniform heating of the shaft 120 in chamber 156 .
  • FIGS. 5 and 6 show another exemplary embodiment.
  • a gas delivery system includes a seal gas passageway 222 extending through stator 212 to a port 254 . Seal gas exiting port 254 enters a groove 255 in the stator 212 .
  • a distributor in the form of an arc segment or full cylinder 240 having ends 278 is disposed proximately of the vent 254 within groove 255 .
  • Distributor 240 may be fixed within groove 255 mechanically, for example, by a friction fit or a fastener or, chemically, for example, by an adhesive or a weld.
  • a midpoint of distributor 240 may be positioned between vent 254 and the rotor shaft of compressor 210 to receive seal gas exiting vent 254 . Seal gas exiting vent 254 may initially be deflected and thus urged along the groove 255 , for example, clockwise and counterclockwise. Seal gas may also pass through any of holes 276 .
  • seal gas may be distributed about the rotor shaft of compressor 210 and may thereby be prevented or inhibited from forming a localized high temperature area on or near the rotor shaft during a temporary shutdown of compressor 210 .
  • Distributor 240 may be provided within groove 255 as part of the manufacturing process of compressor 210 , i.e. as original equipment, or alternatively, distributor 240 may be provided as an aftermarket product introduced to groove 255 during a retrofit.
  • distributor 240 is shown as an arc segment having a plurality of holes 260 ; holes 260 are located on a cylindrical surface, in particular, they are arranged circularly according to a number (specifically five) of parallel circles; holes 260 are arranged all around the rotor shaft; according to the example of FIG. 6 , they are arranged regularly all around the rotor shaft.
  • distributor 240 may be provided in other configurations as well.
  • distributor 240 may be provided without holes 276 such that the entirety of seal gas received by the distributor 240 is deflected along groove 255 .
  • distributor 240 may be provided in a full ring configuration or a series of ring segments.
  • the size and configuration of the holes 260 in distributor 240 may also vary. For example, if distributor 240 is provided as a series of ring segments, the space between each segment may define a plurality of holes through which the flow of seal gas may be controlled.
  • a method ( 1000 ) of operating a turbo machine including an end seal on a rotor shaft thereof can include steps of delivering ( 1002 ) a seal gas to the end seal during turbo machine standstill and distributing ( 1004 ) the seal gas about the rotor shaft through a plurality of holes arranged all around said rotor shaft to prevent uneven heating of the rotor shaft.
  • seal gas distributor has been described as component of the compressor, a seal gas distributor according to the present invention may be provided as a component of the end seal itself.
  • a seal gas delivery system may be configured such that the distributor may be incorporated into a dry gas seal cartridge.
  • the seal gas comes fluidly to the seal gas distributor from a container which is part of a turbo machine; such container may be small or big, and not necessarily dedicated only to the function of containing the seal gas.

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)
  • Sealing Using Fluids, Sealing Without Contact, And Removal Of Oil (AREA)
  • Turbine Rotor Nozzle Sealing (AREA)
US14/397,023 2012-04-27 2013-04-25 Compressor, seal gas delivery, and method Abandoned US20150118018A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
ITCO2012A000020 2012-04-27
IT000020A ITCO20120020A1 (it) 2012-04-27 2012-04-27 Compressore, alimentazione del gas di tenuta e metodo
PCT/EP2013/058663 WO2013160416A1 (en) 2012-04-27 2013-04-25 Compressor, seal gas delivery, and method

Publications (1)

Publication Number Publication Date
US20150118018A1 true US20150118018A1 (en) 2015-04-30

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ID=46466641

Family Applications (1)

Application Number Title Priority Date Filing Date
US14/397,023 Abandoned US20150118018A1 (en) 2012-04-27 2013-04-25 Compressor, seal gas delivery, and method

Country Status (11)

Country Link
US (1) US20150118018A1 (ko)
EP (1) EP2841825B1 (ko)
JP (1) JP6266595B2 (ko)
KR (1) KR20150020274A (ko)
CN (1) CN104395653B (ko)
AU (1) AU2013254655A1 (ko)
CA (1) CA2870624A1 (ko)
IT (1) ITCO20120020A1 (ko)
MX (1) MX2014012988A (ko)
RU (1) RU2611136C2 (ko)
WO (1) WO2013160416A1 (ko)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20160024953A1 (en) * 2014-07-26 2016-01-28 Bob Mischo Fluid Flow Machine
CN107795340A (zh) * 2016-09-07 2018-03-13 通用电气公司 涡轮机温度控制系统
US20190003481A1 (en) * 2015-07-30 2019-01-03 Nuovo Pignone Tecnologie Srl Dry gas seal cooling arrangement and method
US10563663B2 (en) 2018-04-06 2020-02-18 Solar Turbines Incorporated Nitrogen purge of compressor dry seal
US10662798B2 (en) 2015-10-22 2020-05-26 Man Energy Solutions Se Dry gas sealing system, and turbomachine comprising a dry gas sealing system

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6330790B1 (en) * 1999-10-27 2001-12-18 Alliedsignal, Inc. Oil sump buffer seal
US6976679B2 (en) * 2003-11-07 2005-12-20 The Boeing Company Inter-fluid seal assembly and method therefor
US7544039B1 (en) * 2006-06-14 2009-06-09 Florida Turbine Technologies, Inc. Dual spool shaft with intershaft seal

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CH585361A5 (ko) * 1975-06-10 1977-02-28 Bbc Brown Boveri & Cie
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JPS6223503A (ja) * 1985-07-22 1987-01-31 Mitsubishi Heavy Ind Ltd タ−ボ機械の軸シ−ル装置
US5217233A (en) * 1989-10-30 1993-06-08 John Crane Inc. Spiral groove seal system for sealing a high pressure gas
US5375853B1 (en) * 1992-09-18 1998-05-05 Crane John Inc Gas lubricated barrier seal
US5718560A (en) * 1995-12-29 1998-02-17 Sulzer Turbo Ag Turbocompressor for non-ideal process gases
RU2172440C1 (ru) * 2000-03-13 2001-08-20 Тярасов Анатолий Кириллович Торцовое уплотнение вращающегося вала
US7600967B2 (en) * 2005-07-30 2009-10-13 United Technologies Corporation Stator assembly, module and method for forming a rotary machine
US7854584B2 (en) * 2007-05-24 2010-12-21 General Electric Company Barrier sealing system for centrifugal compressors
DE102009012038B4 (de) * 2009-03-10 2014-10-30 Siemens Aktiengesellschaft Wellendichtung für eine Strömungsmaschine
JP4874362B2 (ja) * 2009-03-24 2012-02-15 株式会社日立プラントテクノロジー 高速回転機器用軸封装置
JP5535749B2 (ja) * 2010-04-28 2014-07-02 三菱重工業株式会社 ドライガスシール構造

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6330790B1 (en) * 1999-10-27 2001-12-18 Alliedsignal, Inc. Oil sump buffer seal
US6976679B2 (en) * 2003-11-07 2005-12-20 The Boeing Company Inter-fluid seal assembly and method therefor
US7544039B1 (en) * 2006-06-14 2009-06-09 Florida Turbine Technologies, Inc. Dual spool shaft with intershaft seal

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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20160024953A1 (en) * 2014-07-26 2016-01-28 Bob Mischo Fluid Flow Machine
US10465547B2 (en) * 2014-07-26 2019-11-05 Man Energy Solutions Se Fluid flow machine using a gaseous medium for temperature control of a dry gas seal
US20190003481A1 (en) * 2015-07-30 2019-01-03 Nuovo Pignone Tecnologie Srl Dry gas seal cooling arrangement and method
US10677255B2 (en) * 2015-07-30 2020-06-09 Nuovo Pignone Srl Dry gas seal cooling arrangement and method
US10662798B2 (en) 2015-10-22 2020-05-26 Man Energy Solutions Se Dry gas sealing system, and turbomachine comprising a dry gas sealing system
CN107795340A (zh) * 2016-09-07 2018-03-13 通用电气公司 涡轮机温度控制系统
US10563663B2 (en) 2018-04-06 2020-02-18 Solar Turbines Incorporated Nitrogen purge of compressor dry seal

Also Published As

Publication number Publication date
MX2014012988A (es) 2015-01-26
KR20150020274A (ko) 2015-02-25
WO2013160416A1 (en) 2013-10-31
CN104395653A (zh) 2015-03-04
EP2841825B1 (en) 2020-05-27
EP2841825A1 (en) 2015-03-04
CA2870624A1 (en) 2013-10-31
JP6266595B2 (ja) 2018-01-24
ITCO20120020A1 (it) 2013-10-28
RU2611136C2 (ru) 2017-02-21
AU2013254655A1 (en) 2014-10-30
RU2014141999A (ru) 2016-06-20
CN104395653B (zh) 2017-05-24
JP2015520317A (ja) 2015-07-16

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AS Assignment

Owner name: NUOVO PIGNONE SRL, ITALY

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:BALDASSARRE, LEONARDO;BERNOCCHI, ANDREA;REEL/FRAME:034035/0860

Effective date: 20130201

STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION