EP0194474A2 - Méthode pour le contrôle de la cavitation - Google Patents

Méthode pour le contrôle de la cavitation Download PDF

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Publication number
EP0194474A2
EP0194474A2 EP86102057A EP86102057A EP0194474A2 EP 0194474 A2 EP0194474 A2 EP 0194474A2 EP 86102057 A EP86102057 A EP 86102057A EP 86102057 A EP86102057 A EP 86102057A EP 0194474 A2 EP0194474 A2 EP 0194474A2
Authority
EP
European Patent Office
Prior art keywords
cavitation
measured
delivery unit
microprocessor
pump
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.)
Granted
Application number
EP86102057A
Other languages
German (de)
English (en)
Other versions
EP0194474B1 (fr
EP0194474A3 (en
Inventor
Klaus Metzger
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.)
Metzger Klaus
Original Assignee
Individual
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
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=6265137&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=EP0194474(A2) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Individual filed Critical Individual
Priority to AT86102057T priority Critical patent/ATE96505T1/de
Publication of EP0194474A2 publication Critical patent/EP0194474A2/fr
Publication of EP0194474A3 publication Critical patent/EP0194474A3/de
Application granted granted Critical
Publication of EP0194474B1 publication Critical patent/EP0194474B1/fr
Anticipated expiration legal-status Critical
Revoked legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17D—PIPE-LINE SYSTEMS; PIPE-LINES
    • F17D1/00—Pipe-line systems
    • F17D1/20—Arrangements or systems of devices for influencing or altering dynamic characteristics of the systems, e.g. for damping pulsations caused by opening or closing of valves
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B11/00—Equalisation of pulses, e.g. by use of air vessels; Counteracting cavitation
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D15/00—Control, e.g. regulation, of pumps, pumping installations or systems
    • F04D15/0066—Control, e.g. regulation, of pumps, pumping installations or systems by changing the speed, e.g. of the driving engine
    • 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
    • F04D29/66—Combating cavitation, whirls, noise, vibration or the like; Balancing
    • F04D29/669—Combating cavitation, whirls, noise, vibration or the like; Balancing especially adapted for liquid pumps
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17D—PIPE-LINE SYSTEMS; PIPE-LINES
    • F17D1/00—Pipe-line systems
    • F17D1/02—Pipe-line systems for gases or vapours
    • F17D1/065—Arrangements for producing propulsion of gases or vapours
    • F17D1/07—Arrangements for producing propulsion of gases or vapours by compression

Definitions

  • the invention relates to a method for setting F örderaggregaten for the transport of liquids and / or gases in pipelines, wherein the cavitation is measured as the output value for the setting.
  • Conveyor units in connection with pipelines are generally used for transport or conveying, centrifugal pumps, displacement pumps or water ring pumps (vacuum pumps) being mentioned.
  • cavitation describes a phenomenon that occurs when the Pressure in a liquid, for example due to excessive speed, drops in some places to the evaporation pressure. The resulting steam bubbles collapse again at higher pressure, and the "blows" associated with this lead to considerable stress on the delivery unit and the pipelines.
  • the cavitation is noticeable by an increase in the noise level and an uneven running of the delivery unit. So-called pulsating work can also occur. Along with this, the feed conditions are significantly deteriorated, so that the efficiency of the F örderaggregates decreases. Finally, cavitation can even lead to material destruction (see the literas mentioned above door positions).
  • German published patent application 32 36 815 has already made known a monitoring and control device on pipelines for the transport of liquids for suppressing cavitation. So far, we have limited our to measuring physical quantities such as temperature or liquid level, It is proposed there to measure the cavitation directly by means of a pressure transducer in the form of a measuring membrane with foil strain gauges. Using a microprocessor that processes the measured cavitation values, the speed of a centrifugal pump can be changed until an optimal operating state occurs without any cavitation.
  • the invention takes the novel way of deliberately maintaining a certain minimal residual cavitation. So far - although inadequate - care has been taken to eliminate the cavitation as completely as possible, the invention surprisingly provides for the measure to allow a minimally remaining cavitation, albeit a controllable one.
  • This unprecedented process step is based on the consideration of keeping the 4 n harmful disturbance variable "cavitation" to a small extent during operation, so that the disturbance variable remains under control at all times, so to speak.
  • the residual cavitation can easily be chosen so low that there are no fear of harmful side effects on the delivery unit and on the pipelines. It is sufficient if the residual cavitation is just barely measurable.
  • An important advantage of the invention is that the provided ongoing detection or measurement of the cavitation allows the delivery unit to be switched off if the measured cavitation is harmful and before cavitation limit that can be entered. Basically, a completely self-regulating system is created, in which the delivery quantities are "adjusted" in accordance with the different operating conditions so that manual monitoring can be dispensed with. If a critical limit is exceeded, the corresponding system can be switched off automatically.
  • the invention can also be used in water ring pumps.
  • the fresh water supply was increased or additional ballast gas or air was provided to counteract the harmful cavitation that had occurred.
  • the fresh water can now be Consumption and also not only limit the use of ballast gas or air, but even avoid the latter completely, since the pump speed can be reduced until the capacity of the pump matches the gas / air volume and the cavitation is acceptable.
  • a multi-stage evaporation plant 10 is shown schematically in FIG. 1.
  • the liquid accumulated in a first stage into a liquid container 12 is conveyed into a liquid container 14 of a further stage by means of a centrifugal pump 16. There the liquid has a liquid level (level) 20.
  • the liquid is further conveyed through a pipeline 22 by means of a centrifugal pump 18.
  • a centrifugal pump 18 On the pressure side of the centrifugal pump 18 or the pipeline 22, the cavitation is now measured at a pipe branch 24.
  • the measured values are fed to a microprocessor 26 which, via a frequency converter 28, influences an electric motor 30 for adjusting the speed of the centrifugal pump 18.
  • the The speed of the centrifugal pump 18 is set such that a minimal residual cavitation is maintained (which will be explained in more detail below with reference to FIGS. 4 and 5).
  • the pipe branch 24 contains a measuring membrane 32 with glued-on foil strain gauges 34.
  • Flexible separating rings 36 are provided in the area of a flare 38 to separate and isolate the measuring membrane 32 from the pipeline 22, which act as a support for the flexible seals 36 serves.
  • a clamping device which is necessary per se for bracing the flexible seals 36 and the measuring membrane 32 is not shown in FIGS. 2 and 3.
  • Fig. 3 shows a further embodiment, wherein the measuring membrane 32 is arched to ensure the required mechanical resistance both in vacuum and in overpressure.
  • Cavitation 42 is present in the area labeled 1, while area II indicates a pulsation 44.
  • Area "III” represents normal operation 46, which is again specified separately in area IV as the condition referred to in the aforementioned German Offenlegungsschrift 32 36 815 as optimal operating condition 48.
  • the area V represents a filling curve 50, i.e. a state is shown as it occurs when the suction side of the centrifugal pump 18 in FIG. 1 is filled after an insufficient change in the rotational speed when the liquid level 20 of the liquid container 14 rises.
  • the diagram 52 in FIG. 5 shows the operating state realized with the invention, in which a minimal residual cavitation 54 is deliberately maintained, and this deviates from the operating state 48 shown in area IV in FIG. 4.
  • örderaggregaten F Another significant advantage of the invention is given in örderaggregaten F, whose speed can be changed. Since the possibility of measuring the cavitation is provided, a cavitation limit value can easily be set at which the system is switched off or an alarm is given.
  • the invention advantageously allows a considerable restriction of fresh water consumption and the use of ballast gas or air, since the pump speed in the method according to the invention is regulated down until the capacity of the pump matches the gas / air volume and the cavitation is depressed to the remaining cavitation 54.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)
  • Control Of Positive-Displacement Pumps (AREA)
  • Hydraulic Turbines (AREA)
  • Reciprocating Pumps (AREA)
  • Physical Or Chemical Processes And Apparatus (AREA)
  • Control Of Conveyors (AREA)
  • Details Of Valves (AREA)
  • Control Of Non-Electrical Variables (AREA)
EP86102057A 1985-03-14 1986-02-18 Méthode pour le contrôle de la cavitation Revoked EP0194474B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT86102057T ATE96505T1 (de) 1985-03-14 1986-02-18 Verfahren zur kavitations-einstellung.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19853509072 DE3509072A1 (de) 1985-03-14 1985-03-14 Verfahren zur kavitations-einstellung
DE3509072 1985-03-14

Publications (3)

Publication Number Publication Date
EP0194474A2 true EP0194474A2 (fr) 1986-09-17
EP0194474A3 EP0194474A3 (en) 1989-03-08
EP0194474B1 EP0194474B1 (fr) 1993-10-27

Family

ID=6265137

Family Applications (1)

Application Number Title Priority Date Filing Date
EP86102057A Revoked EP0194474B1 (fr) 1985-03-14 1986-02-18 Méthode pour le contrôle de la cavitation

Country Status (9)

Country Link
EP (1) EP0194474B1 (fr)
JP (1) JPS61283779A (fr)
CN (1) CN86101484A (fr)
AT (1) ATE96505T1 (fr)
AU (1) AU5471386A (fr)
DE (2) DE3509072A1 (fr)
DK (1) DK107386A (fr)
FI (1) FI861033A7 (fr)
ZA (1) ZA861395B (fr)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0964158A3 (fr) * 1998-06-12 2000-08-16 Linde Aktiengesellschaft Procédé d'opération d'une pompe pour refrigérants
EP0947755A3 (fr) * 1998-04-04 2001-07-11 Forschungszentrum Rossendorf e.V. Dispositif pour éviter un pic de cavitation lors de la fermeture rapide d'un conduit servant a transporter un fluide
CN109681474A (zh) * 2019-01-21 2019-04-26 中国科学院工程热物理研究所 一种抑制离心泵空化的自动调节装置及方法
CN110307469A (zh) * 2019-07-24 2019-10-08 中国海洋石油集团有限公司 一种lng接收站高压泵系统及其控制方法
CN110985449A (zh) * 2019-12-04 2020-04-10 武汉理工大学 一种大型邮轮供水系统及离心泵防气蚀装置

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19517289A1 (de) * 1995-05-11 1996-11-14 Klein Schanzlin & Becker Ag Überwachungssystem zur Feststellung einer Kavitationsintensität
DE19645129A1 (de) * 1996-11-04 1998-05-07 Abb Patent Gmbh Verfahren zum kavitiationsfreien Betrieb einer drehzahlgeregelten Pumpe
DE19858946A1 (de) * 1998-12-09 2000-06-15 Ver Energiewerke Ag Verfahren zur Feststellung von Kavitation an einer mehrstufigen Kreiselpumpe
CN101520391B (zh) * 2009-04-01 2011-01-05 奇瑞汽车股份有限公司 一种发动机冷却系统台架气蚀测试方法
JP5597597B2 (ja) * 2011-06-09 2014-10-01 株式会社神戸製鋼所 発電装置
US9255578B2 (en) * 2012-07-31 2016-02-09 Fisher-Rosemount Systems, Inc. Systems and methods to monitor pump cavitation
JP6639013B2 (ja) * 2016-03-14 2020-02-05 株式会社神戸製鋼所 樹脂ペレタイザ装置、及び、キャビテーション監視方法
CN107906058B (zh) * 2017-10-31 2019-07-23 中广核工程有限公司 一种防止核电厂真空泵汽蚀的监视系统和方法
JP7729284B2 (ja) * 2022-08-05 2025-08-26 横河電機株式会社 検知装置、検知方法及び検知システム

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3236815A1 (de) 1982-10-05 1984-04-05 Klaus Dipl.-Ing.(FH) 6831 Brühl Metzger Ueberwachungs- und kontrolleinrichtung an rohrleitungen zum transport von fluessigkeiten zur unterdrueckung von kavitation und zur verbesserung der betriebsbedingungen

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT306402B (de) * 1970-12-23 1973-04-10 List Hans Dehnmeßstreifen-Meßwandler, insbesondere Druckwandler
JPS5177905A (ja) * 1974-12-27 1976-07-06 Tokyo Shibaura Electric Co Denjihonpusochi
US4330238A (en) * 1980-03-04 1982-05-18 The United States Of America As Represented By The Secretary Of The Navy Automatic actuator for variable speed pump
JPS57105580A (en) * 1980-12-19 1982-07-01 Hitachi Zosen Corp Control method for pump operation
JPS57159981A (en) * 1981-03-30 1982-10-02 Hitachi Constr Mach Co Ltd Abnormal pressure indicator in suction side circuit of hydraulic pump
JPS57183582A (en) * 1981-05-08 1982-11-11 Hitachi Zosen Corp Operational control method of pump
CH651111A5 (fr) * 1982-07-28 1985-08-30 Cerac Inst Sa Installation de pompage et procede de mise en action de celle-ci.
JPS5968582A (ja) * 1982-10-14 1984-04-18 Mitsubishi Heavy Ind Ltd 浚渫ポンプのキヤビテ−シヨン限界自動設定装置
FR2535408A1 (fr) * 1982-10-28 1984-05-04 Snecma Dispositif et procede de detection de la garde a la cavitation d'une pompe volumetrique

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3236815A1 (de) 1982-10-05 1984-04-05 Klaus Dipl.-Ing.(FH) 6831 Brühl Metzger Ueberwachungs- und kontrolleinrichtung an rohrleitungen zum transport von fluessigkeiten zur unterdrueckung von kavitation und zur verbesserung der betriebsbedingungen

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
"Kreiselpumpenlexikon", pages: 121 - 122
FUCHSLOCHER/SCHULZ: "Die Pumpen", 1965, SPRINGER VERLAG, pages: 100 - 109

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0947755A3 (fr) * 1998-04-04 2001-07-11 Forschungszentrum Rossendorf e.V. Dispositif pour éviter un pic de cavitation lors de la fermeture rapide d'un conduit servant a transporter un fluide
EP0964158A3 (fr) * 1998-06-12 2000-08-16 Linde Aktiengesellschaft Procédé d'opération d'une pompe pour refrigérants
CN109681474A (zh) * 2019-01-21 2019-04-26 中国科学院工程热物理研究所 一种抑制离心泵空化的自动调节装置及方法
CN109681474B (zh) * 2019-01-21 2023-08-18 中国科学院工程热物理研究所 一种抑制离心泵空化的自动调节装置及方法
CN110307469A (zh) * 2019-07-24 2019-10-08 中国海洋石油集团有限公司 一种lng接收站高压泵系统及其控制方法
CN110985449A (zh) * 2019-12-04 2020-04-10 武汉理工大学 一种大型邮轮供水系统及离心泵防气蚀装置

Also Published As

Publication number Publication date
ZA861395B (en) 1986-11-26
CN86101484A (zh) 1987-01-07
DE3509072C2 (fr) 1987-06-25
FI861033A0 (fi) 1986-03-13
DK107386D0 (da) 1986-03-10
DK107386A (da) 1986-09-15
DE3509072A1 (de) 1986-09-25
AU5471386A (en) 1986-09-18
FI861033L (fi) 1986-09-15
ATE96505T1 (de) 1993-11-15
JPS61283779A (ja) 1986-12-13
DE3689199D1 (de) 1993-12-02
EP0194474B1 (fr) 1993-10-27
FI861033A7 (fi) 1986-09-15
EP0194474A3 (en) 1989-03-08

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