EP0956452A1 - Impeller for a liquid ring machine - Google Patents

Impeller for a liquid ring machine

Info

Publication number
EP0956452A1
EP0956452A1 EP97953620A EP97953620A EP0956452A1 EP 0956452 A1 EP0956452 A1 EP 0956452A1 EP 97953620 A EP97953620 A EP 97953620A EP 97953620 A EP97953620 A EP 97953620A EP 0956452 A1 EP0956452 A1 EP 0956452A1
Authority
EP
European Patent Office
Prior art keywords
impeller
liquid ring
ring machine
support disk
grooves
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
EP97953620A
Other languages
German (de)
French (fr)
Other versions
EP0956452B1 (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

Links

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
  • a generic liquid ring machine is known from the patent DE-195 169 94 Cl.
  • this machine When operating this machine with e.g. hard, i.e. calcareous water, there is limescale deposits in the inner casing. The thickness of the lime layer increases depending on the temperature. A particularly critical case is reached when e.g. the axial gaps between the impeller and the inner casing grow over with lime.
  • the impeller 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. Under certain circumstances, this may result in material breakage or engine damage. The same can occur with increasing layers of corrosion.
  • the invention aims to reduce this layer growth on the inside of the housing of a generic liquid ring machine. According to the invention the object is achieved in that there is at least one recess for edge formation on the end face of the impeller hub and / or on the back of the support disk.
  • FIG 1 grooves in the front of the impeller hub
  • 2 shows a radial groove or a radial slot in the rear of the supporting disk
  • 3 shows offset grooves in the end face of the impeller hub of a liquid ring machine for high vacuum.
  • FIG 1 shows in cross section an impeller 1 which has grooves 3 on the end face of the impeller hub 2, which is designed as a sealing surface 7.
  • FIG 2 shows in longitudinal section of the impeller 1, which has 4 depressions with edge formation 8 on the rear side of the support disk, which in this case is a slot
  • 3 shows in cross section the impeller 1, which has grooves 3 offset by 180 ° on the end face of the impeller hub 2, but each has the sealing surface
  • FIG. 5 show a perspective view of slots 6 in the support disk and grooves 3 in the impeller hub end face 2.

Landscapes

  • 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

Beschreibungdescription
Laufrad für eine FlüssigkeitsringmaschineImpeller for a liquid ring machine
Die Erfindung betrifft ein Laufrad für eine Flüssigkeitsring- maschineThe invention relates to an impeller for a liquid ring machine
Eine gattungsgemäße Flüssigkeitsringmaschine ist durch die Patentschrift DE-195 169 94 Cl bekannt. Bei Betrieb dieser Maschine 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 Ge- häuse führen. Unter Umständen sind Materialbrüche oder Motorschäden die Folge. Der gleiche Fall kann bei wachsenden Kor- rosionsschichten auftreten.A generic liquid ring machine is known from the patent DE-195 169 94 Cl. When operating this machine with e.g. hard, i.e. calcareous water, there is limescale deposits in the inner casing. The thickness of the lime layer increases depending on the temperature. A particularly critical case is reached when e.g. the axial gaps between the impeller and the inner casing grow over with 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. Under certain circumstances, this may result in material breakage or engine damage. The same can occur with increasing layers of corrosion.
Gegen diese Erscheinungen gibt es bisher bei Flüssigkeits- ringmaschinen keine zielgerichteten konstruktiven Maßnahmen.So far, there have been no targeted constructive measures in liquid ring machines against these phenomena.
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 Um- weltverträglichkeit 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 . Erfindungsgemäß wird die Aufgabe dadurch gelöst, daß sich an der Stirnseite der Laufradnabe und/oder an der Tragscheibenruckseite mindestens eine Vertiefung zur Kantenbildung befindet. Durch Anordnungen von Vertiefungen mit Kantenbildung an der Tragscheibenruckseite 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 Ra- des 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 Tragscheibenruckseite und der Laufradnabenstirnseite keine radial durchgehenden Vertiefungen aufweisen.In this special case, chemical additives in the water or ionic accelerators can reduce the lime content by binding the lime in the water or reducing the lime ions in the added water. In addition to the questionable environmental compatibility, the costs incurred for this are enormous and unsuitable for corrosion problems, for example. The invention aims to reduce this layer growth on the inside of the housing of a generic liquid ring machine. According to the invention the object is achieved in that there is at least one recess for edge formation on the end face of the impeller hub and / or on the back of the support disk. By arranging recesses with edge formation on the rear side of the support disk and / or on the end face of the impeller hub, the growing layers are continuously scraped off and transported to the outside with the operating liquid or discharged through the support disk slot. A complete overgrowth of the axial gaps until the wheel locks or an axial pushing away is no longer possible. It is advisable to choose the total width of the depressions with edge formation not larger than 2% of the wheel circumference. Combinations of different depressions that lead to edge formation are possible. In this way, material bores can be combined with grooves and / or slots, just like grooves with through bores. An essentially radial alignment of the depression for edge formation increases the area to be covered. In order to obtain a good gap seal even in a high vacuum, the sealing surfaces of the back of the support disk and the end of the impeller hub should not have any radially continuous recesses.
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 Geräu- schentwicklung der Flüssigkeitsringmaschine. Anhand eines in der Zeichnung dargestellten Ausführungsbeispiels einer Flüssigkeitsringmaschine wird die Erfindung nachfolgend näher be- schrieben. Es zeigt:Further configurations can be found in the claims. Such changes to the liquid ring machine did not show any negative effects on the pump characteristic, 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 Nuten in der Stirnseite der LaufradnabeFIG 1 grooves in the front of the impeller hub
FIG 2 eine radiale Nut bzw. einen radialen Schlitz in der Tragscheibenruckseite, FIG 3 versetzte Nuten in der Stirnseite der Laufradnabe einer Flüssigkeitsringmaschine für Hochvakuum.2 shows a radial groove or a radial slot in the rear of the supporting disk, 3 shows offset grooves in the end face of the impeller hub of a liquid ring machine for high vacuum.
Fig 4 perspektivische Darstellung des LaufradesFig. 4 perspective view of the impeller
(Stirnseite der Laufradnabe im Vordergrund)(Front of the impeller hub in the foreground)
FIG 5 perspektivische Darstellung des Laufrades (Tragscheibenruckseite im Vordergrund)5 shows a perspective view of the impeller (support disk rear side 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 Tragscheibenruckseite 4 Vertiefungen mit Kantenbildung 8 aufweist, die in diesem Fall als Schlitz1 shows in cross section an impeller 1 which has grooves 3 on the end face of the impeller hub 2, which is designed as a sealing surface 7. FIG 2 shows in longitudinal section of the impeller 1, which has 4 depressions with edge formation 8 on the rear side of the support disk, which in this case is a slot
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 Dichtfläche6 and groove 3 are formed. 3 shows in cross section the impeller 1, which has grooves 3 offset by 180 ° on the end face of the impeller hub 2, but each has the sealing surface
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 2.7 Do not fully penetrate the impeller hub 1. 4 and FIG. 5 show a perspective view of slots 6 in the support disk and grooves 3 in the impeller hub end face 2.
Im Betrieb dieser Flüssigkeitsringmaschine schaben die Kanten 8 dieser Schlitze 6 oder Nuten 3 die wachsenden Schichten vonIn the operation of this liquid ring machine, the edges 8 of these slots 6 or grooves 3 scrape the growing layers of
Kalk oder anderen unerwünschten Materialablagerungen (z.B. Korrosionsprodukte) auf der Innenseite des Flüssigkeitsma- schinengehäuses 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 Tragscheibenruckseite 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. Lime or other undesirable material deposits (eg corrosion products) on the inside of the liquid machine housing continuously. The scraped-off material is discharged radially outwards or axially through the support disk slot during operation. For special requirements, for example high vacuum, it makes sense not to provide the sealing surfaces 7 of the impeller hub 2 and the back of the supporting disk 4 with radially continuous grooves 3 or slots 6, but rather, as shown in FIG. 3 shown to arrange the grooves 3 offset. These staggered grooves 3 can be such be formed so that they cover the same area as radially continuous grooves 3rd

Claims

PatentansprücheLaufrad für eine Flüssigkeitsringmaschine Impeller for a liquid ring machine
1. Laufrad (1) für eine Flüssigkeitsringmaschine, das eine Vielzahl von mit der Nabe des Laufrades und einer Tragscheibe verbundenen Schaufel aufweist, wobei Stirnseite der Laufradnabe und Tragscheibenruckseite Dichtflächen aufweisen, d a d u r c h g e k e n n z e i c h - n e t , daß sich an der Stirnseite der Laufradnabe (2) und/oder an der Tragscheibenruckseite (4) mindestens eine Vertiefung zur Kantenbildung (8) befindet.1. Impeller (1) for a liquid ring machine, which has a plurality of blades connected to the hub of the impeller and a support disk, the end face of the impeller hub and the back face of the support disk having sealing surfaces, characterized in that on the end face of the impeller hub (2) and / or at least one recess for edge formation (8) is located on the back of the support disk (4).
2. Laufrad (1) für eine Flüssigkeitsringmaschine nach An- Spruch 1, d a d u r c h g e k e n n z e i c h n e t , daß die Vertiefung zur Kantenbildung (8) aus Nuten (3) und/oder Sackbohrungen besteht .2. Impeller (1) for a liquid ring machine according to claim 1, so that the recess for edge formation (8) consists of grooves (3) and / or blind holes.
3. Laufrad (1) für eine Flüssigkeitsringmaschine nach An- spruch 2, d a d u r c h g e k e n n z e i c h n e t , daß die Vertiefungen zur Kantenbildung (8) axial durchgängig sind.3. Impeller (1) for a liquid ring machine according to claim 2, so that the recesses for edge formation (8) are axially continuous.
4. Laufrad (1) für eine Flüssigkeitsringmaschine nach An- spruch 3, d a d u r c h g e k e n n z e i c h n e t , daß die durchgängigen Vertiefungen (8) aus Schlitzen (6) und/oder Bohrungen bestehen.4. impeller (1) for a liquid ring machine according to claim 3, so that the continuous depressions (8) consist of slots (6) and / or bores.
5. Laufrad (1) für eine Flüssigkeitsringmaschine nach einem der vorhergehenden Ansprüche, a d u r c h g e k e n n z e i c h n e t , daß die Nuten (3) und/oder Schlitze (6) im Wesentlichen in radialer Richtung verlaufen. 5. impeller (1) for a liquid ring machine according to one of the preceding claims, characterized in that the grooves (3) and / or slots (6) run essentially in the radial direction.
6. Laufrad (1) für eine Flüssigkeitsringmaschine nach Anspruch 5, d a d u r c h g e k e n n z e i c h n e t , daß die radiale Ausdehnung der Nuten (3) und/oder Schlitze (6) kleiner ist als die radiale Ausdehnung der jeweiligen Dichtfläche an Tragscheiben-rückseite (4) und/oder Laufradnabenstirnseite (2). 6. impeller (1) for a liquid ring machine according to claim 5, characterized in that the radial extent of the grooves (3) and / or slots (6) is smaller than the radial extent of the respective sealing surface on the rear disk (4) and / or Impeller hub face (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 true EP0956452A1 (en) 1999-11-17
EP0956452B1 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)

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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
EP2783073B1 (en) * 2011-11-22 2020-05-27 Sterling Industry Consult GmbH Liquid-ring vacuum pump and impeller for such a pump

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Also Published As

Publication number Publication date
JP2001505276A (en) 2001-04-17
EP0956452B1 (en) 2002-08-07
WO1998028542A1 (en) 1998-07-02
DE19653746C2 (en) 1999-05-06
DE59707939D1 (en) 2002-09-12
DE19653746A1 (en) 1998-06-25
US6082973A (en) 2000-07-04
ATE221962T1 (en) 2002-08-15

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