EP0956452B1 - Impeller for a liquid ring machine - Google Patents

Impeller for a liquid ring machine Download PDF

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Publication number
EP0956452B1
EP0956452B1 EP97953620A EP97953620A EP0956452B1 EP 0956452 B1 EP0956452 B1 EP 0956452B1 EP 97953620 A EP97953620 A EP 97953620A EP 97953620 A EP97953620 A EP 97953620A EP 0956452 B1 EP0956452 B1 EP 0956452B1
Authority
EP
European Patent Office
Prior art keywords
rotor
liquid ring
ring machine
support disk
impeller
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.)
Expired - Lifetime
Application number
EP97953620A
Other languages
German (de)
French (fr)
Other versions
EP0956452A1 (en
Inventor
Rudi Dittmar
Norbert Schmid
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.)
Siemens AG
Original Assignee
Siemens AG
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 Siemens AG filed Critical Siemens AG
Publication of EP0956452A1 publication Critical patent/EP0956452A1/en
Application granted granted Critical
Publication of EP0956452B1 publication Critical patent/EP0956452B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime 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
    • 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
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01C—ROTARY-PISTON OR OSCILLATING-PISTON MACHINES OR ENGINES
    • F01C21/00—Component parts, details or accessories not provided for in groups F01C1/00 - F01C20/00
    • F01C21/08—Rotary pistons
    • 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
    • F04C19/00—Rotary-piston pumps with fluid ring or the like, specially adapted for elastic fluids
    • 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
    • F04C13/00—Adaptations of machines or pumps for special use, e.g. for extremely high pressures
    • F04C13/005—Removing contaminants, deposits or scale from the pump; Cleaning
    • 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

Definitions

  • the invention relates to an impeller for a liquid ring machine
  • the object is achieved in that the front of the impeller hub and / or on the rear of the support disc there is at least one depression for edge formation.
  • the back of the support disc and / or on the front of the The growing layers become impeller hub continuously scraped off and transported to the outside with the operating fluid or discharged through the support plate slot.
  • Combinations of different wells that are used for Edge formation is possible. This is how material bores can be can be combined with grooves and / or slots, just like Grooves with through holes.
  • FIG. 1 shows in cross section an impeller 1 on the front side the impeller hub 2, which is designed as a sealing surface 7 has grooves 3.
  • 2 shows a longitudinal section of the Impeller 1, the 4 recesses on the back of the support disk with edge formation 8, which in this case as a slot 6 and groove 3 are formed.
  • 3 shows this in cross section Impeller 1, which is on the front of the impeller hub 2 by 180 ° has offset grooves 3, but each of the sealing surface 7 Do not fully penetrate the impeller hub 1.
  • Fig. 4 and FIG. 5 show slots 6 in perspective in the support disc and grooves 3 in the impeller hub front Second

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)
  • Applications Or Details Of Rotary Compressors (AREA)
  • Centrifugal Separators (AREA)

Abstract

PCT No. PCT/DE97/02859 Sec. 371 Date Jun. 21, 1999 Sec. 102(e) Date Jun. 21, 1999 PCT Filed Dec. 8, 1997 PCT Pub. No. WO98/28542 PCT Pub. Date Jul. 2, 1998A rotor for a liquid ring machine having a plurality of vanes connected to the rotor hub and a support disk, with the rotor hub face and the support disk back side having sealing surfaces. Recesses with formed edges, capable of scraping off material deposits, are located on the rotor hub face and the support disk back side.

Description

Die Erfindung betrifft ein Laufrad für eine FlüssigkeitsringmaschineThe invention relates to an impeller for a liquid ring machine

Gattungsgemäße Flüssigkeitsringmaschinen sind durch die Patentschriften DE-195 16 994 C1 und die AU-A-83896/75 bekannt. Bei Betrieb dieser Maschinen mit z.B. hartem, d.h. kalkhaltigen Wasser, kommt es zu Kalkablagerungen im Innengehäuse. Die Dicke der Kalkschicht wächst dabei in Abhängigkeit von der Temperatur. Ein besonders kritischer Fall wird erreicht, wenn z.B. durch Kalk die axialen Spalten zwischen Laufrad und Innengehäuse zuwachsen. Bei Betrieb der Maschine, insbesondere bei längerem Stillstand, kann das Laufrad durch diesen Kalk festsitzen oder durch Anlaufen an die Kalkschicht axial verschoben werden. Diese Verschiebung des Laufrades kann an der gegenüberliegenden Seite ebenfalls zum "Fressen" des Laufrades am Gehäuse führen. Unter Umständen sind Materialbrüche oder Motorschäden die Folge. Der gleiche Fall kann bei wachsenden Korrosionsschichten auftreten. Generic liquid ring machines are known from the patents DE-195 16 994 C1 and AU-A-83896/75. If these machines are operated with hard, ie chalky water, there will be limescale deposits in the inner casing. The thickness of the lime layer increases depending on the temperature. A particularly critical case is reached if, for example, the axial gaps between the impeller and the inner casing increase due to lime. When the machine is in operation, especially when the machine is at a standstill for a long time, the impeller can become stuck due to this limescale or be moved axially by striking the limestone layer. This displacement of the impeller on the opposite side can also lead to the impeller "seizing" on the housing. Material breakage or engine damage may result. The same case can occur with growing layers of corrosion.

Gegen diese Erscheinungen gibt es bisher bei Flüssigkeitsringmaschinen keine zielgerichteten konstruktiven Maßnahmen. Chemische Zusätze im Wasser oder ionische Beschleuniger können in diesem speziellen Fall den Kalkgehalt reduzieren, indem sie den Kalk im Wasser binden oder die Kalkionen im zugesetzten Wasser reduzieren. Außer der dabei fragwürdigen Umweltverträglichkeit sind die dafür aufzubringenden Kosten enorm und für z.B. Korrosionsprobleme ungeeignet. Durch die Erfindung wird eine Reduktion dieses Schichtwachstums an der Innenseite des Gehäuses einer gattungsgemäßen Flüssigkeitsringmaschine angestrebt. So far, there are liquid ring machines against these phenomena no targeted constructive measures. Chemical additives in water or ionic accelerators can in this special case reduce the lime content by they bind the lime in the water or the lime ions in the added Reduce water. Except for the questionable environmental impact the costs involved are enormous and for e.g. Corrosion problems unsuitable. Through the Invention is a reduction in this layer growth on the Inside of the housing of a generic liquid ring machine sought.

Erfindungsgemäß wird die Aufgabe dadurch gelöst, daß sich an der Stirnseite der Laufradnabe und/oder an der Tragscheibenrückseite mindestens eine Vertiefung zur Kantenbildung befindet. Durch Anordnungen von Vertiefungen mit Kantenbildung an der Tragscheibenrückseite und/oder an der Stirnseite der Laufradnabe werden die wachsenden Schichten kontinuierlich abgekratzt und mit der Betriebsflüssigkeit nach außen transportiert bzw. durch den Tragscheibenschlitz abgeführt. Ein völliges Zuwachsen der Axialspalte bis zum Festsetzen des Rades oder ein axiales Wegschieben ist somit nicht mehr möglich. Zweckmäßig ist es, die Gesamtbreite der Vertiefungen mit Kantenbildung nicht größer als 2 % des Laufradumfanges zu wählen. Kombinationen verschiedener Vertiefungen, die zur Kantenbildung führen sind möglich. So können Sachbohrungen mit Nuten und/oder Schlitzen kombiniert werden, genauso wie Nuten mit durchgehenden Bohrungen. Eine im wesentliche radiale Ausrichtung der Vertiefung zur Kantenbildung vergrößert die zu überstreichende Fläche. Um auch im Hochvakuum eine gute Spaltabdichtung zu erhalten, sollten die Dichtflächen der Tragscheibenrückseite und der Laufradnabenstirnseite keine radial durchgehenden Vertiefungen aufweisen.According to the invention the object is achieved in that the front of the impeller hub and / or on the rear of the support disc there is at least one depression for edge formation. By arranging depressions with edge formation the back of the support disc and / or on the front of the The growing layers become impeller hub continuously scraped off and transported to the outside with the operating fluid or discharged through the support plate slot. On complete growth of the axial gaps until the wheel is locked or an axial pushing away is no longer possible. It is useful to cover the total width of the wells with edges not more than 2% of the wheel circumference choose. Combinations of different wells that are used for Edge formation is possible. This is how material bores can be can be combined with grooves and / or slots, just like Grooves with through holes. An essentially radial one Alignment of the recess for edge formation enlarged the area to be covered. To be a good one even in high vacuum To obtain gap sealing, the sealing surfaces of the Rear of the support disk and the impeller hub end face none have radially continuous depressions.

Weitere Ausgestaltungen sind den Ansprüchen zu entnehmen. Durch derartige Veränderungen der Flüssigkeitsringmaschine zeigten sich im Laborversuch keine negativen Auswirkungen auf die Pumpenkennlinie, auf den Leistungsbedarf und die Geräuschentwicklung der Flüssigkeitsringmaschine. Anhand eines in der Zeichnung dargestellten Ausführungsbeispiels einer Flüssigkeitsringmaschine wird die Erfindung nachfolgend näher beschrieben. Es zeigt:

FIG 1
Nuten in der Stirnseite der Laufradnabe
FIG 2
eine radiale Nut bzw. einen radialen Schlitz in der Tragscheibenrückseite,
FIG 3
versetzte Nuten in der Stirnseite der Laufradnabe einer Flüssigkeitsringmaschine für Hochvakuum.
Fig 4
perspektivische Darstellung des Laufrades (Stirnseite der Laufradnabe im Vordergrund)
FIG 5
perspektivische Darstellung des Laufrades (Tragscheibenrückseite im Vordergrund)
Further configurations can be found in the claims. Such changes to the liquid ring machine did not show any negative effects on the pump characteristics, the power requirement and the noise level of the liquid ring machine in the laboratory test. The invention is described in more detail below on the basis of an exemplary embodiment of a liquid ring machine shown in the drawing. It shows:
FIG. 1
Grooves in the front of the impeller hub
FIG 2
a radial groove or a radial slot in the rear of the carrier disk,
FIG 3
offset grooves in the front of the impeller hub of a liquid ring machine for high vacuum.
Fig. 4
perspective view of the impeller (front side of the impeller hub in the foreground)
FIG 5
perspective view of the impeller (rear of the support disk in the foreground)

FIG 1 zeigt im Querschnitt ein Laufrad 1, das an der Stirnseite der Laufradnabe 2, die als Dichtfläche 7 ausgebildet ist, Nuten 3 aufweist. FIG 2 zeigt im Längsschnitt des Laufrades 1, das an der Tragscheibenrückseite 4 Vertiefungen mit Kantenbildung 8 aufweist, die in diesem Fall als Schlitz 6 und Nut 3 ausgebildet sind. FIG 3 zeigt im Querschnitt das Laufrad 1, das an der Stirnseite der Laufradnabe 2 um 180° versetzte Nuten 3 aufweist, die aber jeweils die Dichtfläche 7 der Laufradnabe 1 nicht vollständig durchdringen. Fig. 4 und FIG. 5 zeigen in perspektivischer Darstellung Schlitze 6 in der Tragscheibe und Nuten 3 in der Laufradnabenstirnseite 2.1 shows in cross section an impeller 1 on the front side the impeller hub 2, which is designed as a sealing surface 7 has grooves 3. 2 shows a longitudinal section of the Impeller 1, the 4 recesses on the back of the support disk with edge formation 8, which in this case as a slot 6 and groove 3 are formed. 3 shows this in cross section Impeller 1, which is on the front of the impeller hub 2 by 180 ° has offset grooves 3, but each of the sealing surface 7 Do not fully penetrate the impeller hub 1. Fig. 4 and FIG. 5 show slots 6 in perspective in the support disc and grooves 3 in the impeller hub front Second

Im Betrieb dieser Flüssigkeitsringmaschine schaben die Kanten 8 dieser Schlitze 6 oder Nuten 3 die wachsenden Schichten von Kalk oder anderen unerwünschten Materialablagerungen (z.B. Korrosionsprodukte) auf der Innenseite des Flüssigkeitsmaschinengehäuses kontinuierlich ab. Das abgeschabte Material wird durch den Betrieb radial nach außen bzw. axial durch den Tragscheibenschlitz abgeführt. Für spezielle Anforderungen, z.B. Hochvakuum ist es sinnvoll, die Dichtflächen 7 der Laufradnabe 2 und der Tragscheibenrückseite 4 nicht mit radial durchgängigen Nuten 3 bzw. Schlitzen 6 zu versehen, sondern vielmehr, wie in FIG. 3 dargestellt die Nuten 3 versetzt anzuordnen. Diese versetzt angeordneten Nuten 3 können derart ausgebildet werden, daß sie die gleiche Fläche überstreichen, wie radial durchgehende Nuten 3.The edges scrape during the operation of this liquid ring machine 8 of these slots 6 or grooves 3 the growing layers of Lime or other undesirable material deposits (e.g. Corrosion products) on the inside of the liquid machine housing continuously. The scraped material is by the operation radially outwards or axially by the Carrying disc slot removed. For special requirements, e.g. High vacuum, it makes sense to the sealing surfaces 7 of the Impeller hub 2 and the rear of the supporting disc 4 are not radial to provide continuous grooves 3 or slots 6, but rather, as shown in FIG. 3 shows the grooves 3 offset to arrange. These staggered grooves 3 can be such be trained to cover the same area, like radial grooves 3.

Claims (6)

  1. Rotor (1) for a liquid ring machine, having a plurality of vanes connected to the rotor hub and a support disk, whereby the face of the rotor hub (2) and the support disk back side (4) have sealing surfaces, characterised in that the face of the rotor hub (2) and/or support disk back side (4) has at least one recess for forming edges (8), which prevents layers forming on the support disk back side (4) and/or on the face of the rotor hub (2), so that axial clearances cannot be filled to the point where the rotor is jammed or axially displaced.
  2. Rotor (1) for a liquid ring machine according to Claim 1, characterised in that the recess for forming edges (8) consists of grooves (3) and/or pocket holes.
  3. Rotor (1) for a liquid ring machine according to Claim 2, characterised in that the recesses for forming edges (8) are axial through holes.
  4. Rotor (1) for a liquid ring machine according to Claim 3, characterised in that the through recesses (8) consist of slots (6) and/or bore holes.
  5. Rotor (1) for a liquid ring machine according to one of the preceding claims, characterised in that the grooves (3) and/or slots (6) run in a substantially radial direction.
  6. Rotor (1) for a liquid ring machine according to Claim 5, characterised in that the radial dimension of the grooves (3) and/or slots (6) is less than the radial dimension of the respective sealing surface on the support disk back side (4) and/or face of the rotor hub (2).
EP97953620A 1996-12-20 1997-12-08 Impeller for a liquid ring machine Expired - Lifetime EP0956452B1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE19653746 1996-12-20
DE19653746A DE19653746C2 (en) 1996-12-20 1996-12-20 Impeller for a liquid ring machine
PCT/DE1997/002859 WO1998028542A1 (en) 1996-12-20 1997-12-08 Impeller for a liquid ring machine

Publications (2)

Publication Number Publication Date
EP0956452A1 EP0956452A1 (en) 1999-11-17
EP0956452B1 true EP0956452B1 (en) 2002-08-07

Family

ID=7815829

Family Applications (1)

Application Number Title Priority Date Filing Date
EP97953620A Expired - Lifetime EP0956452B1 (en) 1996-12-20 1997-12-08 Impeller for a liquid ring machine

Country Status (6)

Country Link
US (1) US6082973A (en)
EP (1) EP0956452B1 (en)
JP (1) JP2001505276A (en)
AT (1) ATE221962T1 (en)
DE (2) DE19653746C2 (en)
WO (1) WO1998028542A1 (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE508554C2 (en) * 1996-07-10 1998-10-12 Kjell Lindskog Method and device for destruction of objects
US20040202549A1 (en) * 2003-01-17 2004-10-14 Barton Russell H. Liquid ring pump
US20140286797A1 (en) * 2011-11-22 2014-09-25 Matthias Tamm Liquid-Ring Vacuum Pump and Impeller for a Liquid-Ring Vacuum Pump

Family Cites Families (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1525332A (en) * 1922-08-10 1925-02-03 American Steam Pump Company Centrifugal fluid vacuum pump
US1668532A (en) * 1924-09-08 1928-05-01 W L Stewart Rotary machine
US2771860A (en) * 1950-08-22 1956-11-27 Werner P Falk Hydraulic machine
DE1528823B2 (en) * 1963-11-29 1972-02-24 Siemens AG, 1000 Berh u 8000 München IMPELLER FOR SIDE DUCT PUMPS
US3713749A (en) * 1970-09-30 1973-01-30 Nash Engineering Co Motor-driven pedestal-mounted pump assembly and method for manufacturing the same
US3792568A (en) * 1972-08-15 1974-02-19 Jmj Ind Inc Air scrubber
US3894812A (en) * 1974-02-19 1975-07-15 Atlantic Fluidics Inc Liquid ring vacuum pump-compressor
AU8389675A (en) * 1974-08-15 1977-02-17 Grayden P J Pty Ltd Liquid ring vacuum pump
US4112688A (en) * 1976-10-08 1978-09-12 Shaw John B Positive displacement gas expansion engine with low temperature differential
AR216254A1 (en) * 1979-07-11 1979-11-30 Corvetto A ROTARY TYPE GAS COMPRESSOR
WO1985000637A1 (en) * 1983-07-15 1985-02-14 Jimmie Wesley Patterson Lobular type rotary pump
FI882712A (en) * 1988-06-08 1989-12-09 Pentamo Oy VAETSKERINGKOMPRESSOR.
US5017086A (en) * 1989-05-08 1991-05-21 Vickers Incorporated Hydraulic periphery pumps
US5096386A (en) * 1989-11-17 1992-03-17 Sundstrand Corporation Integral liquid ring and regenerative pump
US5100300A (en) * 1990-12-28 1992-03-31 The Nash Engineering Company Liquid ring pumps having rotating lobe liners with end walls
US5197863A (en) * 1990-12-28 1993-03-30 The Nash Engineering Company Bearing fluid distribution systems for liquid ring pumps with rotating lobe liners
US5213479A (en) * 1992-04-09 1993-05-25 The Nash Engineering Company Liquid ring pumps with improved housing shapes
US5318415A (en) * 1992-10-02 1994-06-07 Gramprotex Holdings Inc. Grooved pump chamber walls for flushing fiber deposits
DE19516994C1 (en) * 1995-05-09 1996-10-17 Siemens Ag Fluid ring machine
DE29611342U1 (en) * 1996-06-28 1997-08-14 Speck-Pumpenfabrik Walter Speck KG, 91154 Roth Liquid ring pump
US5867900A (en) * 1997-08-26 1999-02-09 Ecowater Systems, Inc. Plastic coated valve rotor and a method of manufacturing

Also Published As

Publication number Publication date
EP0956452A1 (en) 1999-11-17
WO1998028542A1 (en) 1998-07-02
JP2001505276A (en) 2001-04-17
DE19653746A1 (en) 1998-06-25
DE19653746C2 (en) 1999-05-06
US6082973A (en) 2000-07-04
DE59707939D1 (en) 2002-09-12
ATE221962T1 (en) 2002-08-15

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