US20100086883A1 - Method for reacting self-igniting dusts in a vacuum pump device - Google Patents

Method for reacting self-igniting dusts in a vacuum pump device Download PDF

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Publication number
US20100086883A1
US20100086883A1 US12/438,220 US43822007A US2010086883A1 US 20100086883 A1 US20100086883 A1 US 20100086883A1 US 43822007 A US43822007 A US 43822007A US 2010086883 A1 US2010086883 A1 US 2010086883A1
Authority
US
United States
Prior art keywords
oxygen
dust
vacuum pump
pump device
supplying
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
US12/438,220
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English (en)
Inventor
Uwe Zöllig
Thomas Dreifert
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.)
Leybold GmbH
Original Assignee
Oerlikon Leybold Vacuum GmbH
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 Oerlikon Leybold Vacuum GmbH filed Critical Oerlikon Leybold Vacuum GmbH
Assigned to OERLIKON LEYBOLD VACUUM GMBH reassignment OERLIKON LEYBOLD VACUUM GMBH ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: DREIFERT, THOMAS, ZOLLIG, UWE
Publication of US20100086883A1 publication Critical patent/US20100086883A1/en
Abandoned legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C28/00—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids
    • F04C28/28—Safety arrangements; Monitoring
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C29/00—Component parts, details or accessories of pumps or pumping installations, not provided for in groups F04C18/00 - F04C28/00
    • F04C29/0092—Removing solid or liquid contaminants from the gas under pumping, e.g. by filtering or deposition; Purging; Scrubbing; Cleaning
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D19/00—Axial-flow pumps
    • F04D19/02—Multi-stage pumps
    • F04D19/04—Multi-stage pumps specially adapted to the production of a high vacuum, e.g. molecular 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
    • F04D3/00—Axial-flow pumps
    • F04D3/02—Axial-flow pumps of screw type
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C18/00—Rotary-piston pumps specially adapted for elastic fluids
    • F04C18/08—Rotary-piston pumps specially adapted for elastic fluids of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing
    • F04C18/12—Rotary-piston pumps specially adapted for elastic fluids of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of other than internal-axis type
    • F04C18/14—Rotary-piston pumps specially adapted for elastic fluids of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of other than internal-axis type with toothed rotary pistons
    • F04C18/16—Rotary-piston pumps specially adapted for elastic fluids of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of other than internal-axis type with toothed rotary pistons with helical teeth, e.g. chevron-shaped, screw type
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C2220/00—Application
    • F04C2220/10—Vacuum
    • F04C2220/12—Dry running
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C2280/00—Arrangements for preventing or removing deposits or corrosion
    • F04C2280/02—Preventing solid deposits in pumps, e.g. in vacuum pumps with chemical vapour deposition [CVD] processes
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/8593—Systems
    • Y10T137/85978—With pump
    • Y10T137/85986—Pumped fluid control

Definitions

  • the invention relates to a method for exhaustive reaction of self-igniting dust in a dry-sealed vacuum pump device, as well as a corresponding vacuum pump.
  • the dust also causes a safety hazard to the maintenance personnel of the systems because, in case of faulty operating or unintentional venting of the system, inflammation of the dust cannot be excluded. Such an inflammation may even occur in the filter or in the tubing.
  • One aspect provides a well-aimed exhaustive reaction of oxidizable dust in the vacuum pump.
  • silicon oxide (SiO) is oxidized to silicon dioxide (SiO 2 ), and metals are oxidized to metal oxides. Since it is substantially gas that is conveyed by the vacuum pump and since the absolute mass flow of dust per time unit is relatively small, the present method offers the possibility to accomplish a continuous and controlled exhaustive reaction of the reactive dust. Uncontrolled inflammation of the dust is reliably prevented.
  • the supplying of oxygen can be provided in the form of pure oxygen or in the form of air. The oxygen supply will affect the suction performance of the pump only to a mere negligible extent.
  • the dust quantity introduced into the vacuum pump per time unit is small enough to be continuously burned with a relatively low air-gas ballast while this burning process will not cause damage to the pump. All of the particles leaving the pump again on the pressure side will have undergone an exhaustive reaction. Consequently, a separation of dust can be performed by use of normal dust filters on the pressure side without a danger of uncontrolled reactions. This allows for a simplified and less expensive installation of the vacuum pump. Possible accumulations of dust in the tubing on the exhaust side will not be reactive anymore and thus will be of no concern under the aspect of safety technology.
  • the supplied oxygen-containing gas can be fed into the vacuum pump device at a suitable site, e.g. into the pumping chamber at the entrance to the pump, at a site along the compression chamber, or at the pump exit.
  • Another aspect relates to a dry-sealed vacuum pump device comprising at least one driven compression member and a housing with pump entrance and pump exit.
  • the vacuum pump is characterized in that the housing comprises at least one oxygen entrance provided with a throttle valve for regulating the cross section of the entrance.
  • a dry-sealed vacuum pump Possible embodiments of a dry-sealed vacuum pump are the following: screw pumps, claw-type pumps, Roots pumps, turbo compressors, lateral-channel blowers, dry-sealed rotary-vane pumps, and others.
  • the vacuum pump device can comprise a sole vacuum pump, or a plurality of pumps connected in series and each forming a pump stage.
  • the oxygen can also be introduced into a reaction chamber arranged between two pump stages.
  • a reaction chamber use can be made also of a tube conduit.
  • temperature and pressure sensors are provided for monitoring the reaction in the vacuum pump device.
  • a method for cleansing the vacuum pump device and the feed conduits from dust can reside in that, after the end of the process, the supply of process gas is terminated while the supply of an oxygen-containing gas mixture, e.g. air, through the pump device is continued.
  • an oxygen-containing gas mixture e.g. air
  • the oxygen required for oxidation can also be contained in the buffer gas of a shaft sealing.
  • the oxygen will flow in dosed quantities from the shaft sealing into a pump chamber or into a conduit of the pump device.
  • FIG. 1 is a schematic longitudinal sectional view through the compression chamber of a vacuum pump
  • FIG. 2 is a sectional view taken along line II-II in FIG. 1 .
  • FIG. 3 is a schematic representation for illustrating the principle of the present invention.
  • a vacuum pump in the form of a screw pump.
  • Said pump comprises an elongate housing 10 supporting therein two screw rotors 12 , 14 for rotation in opposite senses.
  • Each screw rotor comprises a helically configured tooth 16 , 18 with a pitch continuously decreasing from the pump entrance 20 to the pump exit 22 , as can be seen in FIG. 1 .
  • the working chamber which in rotating rotors will be traveling in axial direction, is reduced in size from pump entrance 20 towards pump exit 22 .
  • the compression chamber 24 is arranged between the pump entrance and the pump exit.
  • Pump entrance 20 forms the pumping chamber which will be connected to the device that is to be evacuated. Into this pumping chamber, the process gas 38 will be sucked. The process gas contains particles 40 in the form of non-oxidized dust.
  • Pump entrance 20 is connected to an oxygen intake 26 which is laterally arranged on housing 10 and is provided with a throttle valve 28 .
  • Throttle valve 28 can be set to various throttle cross sections so as to regulate the oxygen supply.
  • the oxygen can be pure oxygen or a component of a gas mixture, e.g. of air.
  • the dust will undergo a controlled reaction with the supplied oxygen as soon as, during condensation, an oxygen partial pressure as required for reaction has been reached.
  • Oxygen intake 26 a is located in the region of the mid-length of compression chamber 24 , namely in the middle between the two mutually engaging helically shaped teeth 16 , 18 .
  • a third alternative includes the oxygen intake 26 b arranged on pump exit 22 .
  • FIG. 3 is a schematic representation of the pump with the pump entrance 20 for suctional intake of the process gas 38 .
  • oxygen intake 26 is arranged at the suction connector of pump entrance 20 .
  • the black sphere symbols represent the non-oxidized particles
  • the hollow sphere symbols represent the oxidized particles. Oxidation takes place in compression chamber 24 in dependence on which intake among the oxygen intakes 26 , 26 a , 26 b is in the opened state.
  • the shafts for rotating the screw rotors are designated by 30 .

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Compressors, Vaccum Pumps And Other Relevant Systems (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Applications Or Details Of Rotary Compressors (AREA)
  • Cleaning In General (AREA)
US12/438,220 2006-08-23 2007-08-07 Method for reacting self-igniting dusts in a vacuum pump device Abandoned US20100086883A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE102006039529.8 2006-08-23
DE200610039529 DE102006039529A1 (de) 2006-08-23 2006-08-23 Verfahren zur Abreaktion selbstentzündlicher Stäube in einer Vakuumpumpvorrichtung
PCT/EP2007/058199 WO2008022916A1 (de) 2006-08-23 2007-08-07 Verfahren zur abreaktion selbstentzündlicher stäube in einer vakuumpumpvorrichtung

Publications (1)

Publication Number Publication Date
US20100086883A1 true US20100086883A1 (en) 2010-04-08

Family

ID=38792066

Family Applications (1)

Application Number Title Priority Date Filing Date
US12/438,220 Abandoned US20100086883A1 (en) 2006-08-23 2007-08-07 Method for reacting self-igniting dusts in a vacuum pump device

Country Status (7)

Country Link
US (1) US20100086883A1 (de)
EP (1) EP2054626B1 (de)
JP (1) JP2010501766A (de)
CN (1) CN101535651B (de)
DE (1) DE102006039529A1 (de)
RU (1) RU2009110263A (de)
WO (1) WO2008022916A1 (de)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070231162A1 (en) * 2004-03-26 2007-10-04 Graeme Huntley Vacuum Pump
US20110232689A1 (en) * 2008-10-28 2011-09-29 Oerlikon Leybold Vacuum Gmbh Method for cleaning a vacuum pump
US11293435B2 (en) 2016-08-30 2022-04-05 Leybold Gmbh Vacuum pump screw rotors with symmetrical profiles on low pitch sections
US11300123B2 (en) 2016-08-30 2022-04-12 Leybold Gmbh Screw vacuum pump without internal cooling
US20220341423A1 (en) * 2019-10-07 2022-10-27 Hitachi Industrial Equipment Systems Co., Ltd. Screw compressor

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102007043350B3 (de) * 2007-09-12 2009-05-28 Oerlikon Leybold Vacuum Gmbh Vakuumpumpe sowie Verfahren zur Steuerung einer Gasballastzufuhr zu einer Vakuumpumpe
DE102008030788A1 (de) * 2008-06-28 2009-12-31 Oerlikon Leybold Vacuum Gmbh Verfahren zum Reinigen von Vakuumpumpen
DE102011005464B4 (de) * 2011-03-11 2014-07-17 Fmp Technology Gmbh Fluid Measurements & Projects Vorrichtung zur Erzeugung eines Unterdrucks
JP6100038B2 (ja) * 2013-03-14 2017-03-22 株式会社荏原製作所 真空ポンプ
DE102015118022B4 (de) * 2015-10-22 2024-05-29 Pfeiffer Vacuum Gmbh Rotationsverdrängervakuumpumpe
DE102015121143B4 (de) * 2015-12-04 2023-02-02 Pfeiffer Vacuum Gmbh Mehrwellige Vakuumpumpe
JP7072417B2 (ja) * 2018-03-27 2022-05-20 株式会社日立産機システム スクリュー圧縮機
CN108775286A (zh) * 2018-08-03 2018-11-09 深圳市石金科技股份有限公司 一种干式真空泵的清洁装置
KR102119071B1 (ko) * 2018-11-22 2020-06-04 (주)엘오티베큠 마모 발생을 방지하는 진공펌프

Citations (9)

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Publication number Priority date Publication date Assignee Title
US4919599A (en) * 1988-06-01 1990-04-24 Leybold Aktiengesellschaft Pumping system for a leak detecting device
US5672322A (en) * 1992-01-16 1997-09-30 Leybold Ag Method, dry multi-stage pump and plasmascrubber for converting reactive gases
US6224326B1 (en) * 1998-09-10 2001-05-01 Alcatel Method and apparatus for preventing deposits from forming in a turbomolecular pump having magnetic or gas bearings
US20030007910A1 (en) * 2001-06-22 2003-01-09 Stela Diamant Lazarovich Plasma treatment of processing gases
WO2004036047A1 (en) * 2002-10-14 2004-04-29 The Boc Group Plc Rotary piston vacuum pump with washing installation
US20050142000A1 (en) * 2003-12-01 2005-06-30 Alcatel Plasma-based gas treatment system integrated in a vacuum pump
WO2005093260A1 (en) * 2004-03-26 2005-10-06 The Boc Group Plc Vacuum pump
WO2007066141A1 (en) * 2005-12-09 2007-06-14 Edwards Limited Method of inhibiting a deflagration in a vacuum pump
US20080135066A1 (en) * 2004-12-22 2008-06-12 Christian Beyer Method For Cleaning a Vacuum Screw-Type Pump

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DE2835260A1 (de) * 1978-08-11 1980-02-14 Pfeiffer Vakuumtechnik Verfahren und einrichtung zum schutz der vakuumpumpe gegen reaktionsprodukte beim lpcvd-verfahren
DD143172A1 (de) * 1979-05-17 1980-08-06 Rainer Moeller Verfahren zum abpumpen von hochreaktiven oder toxischen gasen oder daempfen mittels drehschiebervakuumpumpen
JP3402039B2 (ja) * 1995-12-25 2003-04-28 信越半導体株式会社 単結晶製造装置
JP3603578B2 (ja) * 1997-12-27 2004-12-22 信越半導体株式会社 単結晶引上げ装置の不活性ガス回収装置
DE19854235A1 (de) * 1998-11-24 2000-05-25 Wacker Siltronic Halbleitermat Oxidationsvorrichtung und Verfahren zur Passivierung von Stäuben
DE29904411U1 (de) * 1999-03-10 2000-07-20 Ghh Rand Schraubenkompressoren Schraubenkompressor
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Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4919599A (en) * 1988-06-01 1990-04-24 Leybold Aktiengesellschaft Pumping system for a leak detecting device
US5672322A (en) * 1992-01-16 1997-09-30 Leybold Ag Method, dry multi-stage pump and plasmascrubber for converting reactive gases
US6224326B1 (en) * 1998-09-10 2001-05-01 Alcatel Method and apparatus for preventing deposits from forming in a turbomolecular pump having magnetic or gas bearings
US20030007910A1 (en) * 2001-06-22 2003-01-09 Stela Diamant Lazarovich Plasma treatment of processing gases
WO2004036047A1 (en) * 2002-10-14 2004-04-29 The Boc Group Plc Rotary piston vacuum pump with washing installation
US20050142000A1 (en) * 2003-12-01 2005-06-30 Alcatel Plasma-based gas treatment system integrated in a vacuum pump
WO2005093260A1 (en) * 2004-03-26 2005-10-06 The Boc Group Plc Vacuum pump
US7819635B2 (en) * 2004-03-26 2010-10-26 Edwards Limited Vacuum pump with a continuous ignition source
US20080135066A1 (en) * 2004-12-22 2008-06-12 Christian Beyer Method For Cleaning a Vacuum Screw-Type Pump
WO2007066141A1 (en) * 2005-12-09 2007-06-14 Edwards Limited Method of inhibiting a deflagration in a vacuum pump

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070231162A1 (en) * 2004-03-26 2007-10-04 Graeme Huntley Vacuum Pump
US7819635B2 (en) * 2004-03-26 2010-10-26 Edwards Limited Vacuum pump with a continuous ignition source
US20110232689A1 (en) * 2008-10-28 2011-09-29 Oerlikon Leybold Vacuum Gmbh Method for cleaning a vacuum pump
US11293435B2 (en) 2016-08-30 2022-04-05 Leybold Gmbh Vacuum pump screw rotors with symmetrical profiles on low pitch sections
US11300123B2 (en) 2016-08-30 2022-04-12 Leybold Gmbh Screw vacuum pump without internal cooling
US20220341423A1 (en) * 2019-10-07 2022-10-27 Hitachi Industrial Equipment Systems Co., Ltd. Screw compressor
US11933300B2 (en) * 2019-10-07 2024-03-19 Hitachi Industrial Equipment Systems Co., Ltd. Screw compressor having a screw rotor whose pitch changes in an axial direction from a suction end surface toward a discharge end surface

Also Published As

Publication number Publication date
JP2010501766A (ja) 2010-01-21
WO2008022916A1 (de) 2008-02-28
EP2054626B1 (de) 2012-12-05
CN101535651A (zh) 2009-09-16
RU2009110263A (ru) 2010-09-27
EP2054626A1 (de) 2009-05-06
CN101535651B (zh) 2014-05-14
DE102006039529A1 (de) 2008-03-06

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Legal Events

Date Code Title Description
AS Assignment

Owner name: OERLIKON LEYBOLD VACUUM GMBH,GERMANY

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:ZOLLIG, UWE;DREIFERT, THOMAS;REEL/FRAME:023361/0067

Effective date: 20090306

STCB Information on status: application discontinuation

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