EP0680562B1 - Liquid ring machine - Google Patents

Liquid ring machine Download PDF

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Publication number
EP0680562B1
EP0680562B1 EP94904567A EP94904567A EP0680562B1 EP 0680562 B1 EP0680562 B1 EP 0680562B1 EP 94904567 A EP94904567 A EP 94904567A EP 94904567 A EP94904567 A EP 94904567A EP 0680562 B1 EP0680562 B1 EP 0680562B1
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EP
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Prior art keywords
liquid
machine
liquid ring
discharge passage
operating
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EP94904567A
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German (de)
French (fr)
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EP0680562A1 (en
Inventor
Peter Trimborn
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Siemens AG
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Siemens AG
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    • 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
    • F04C19/004—Details concerning the operating liquid, e.g. nature, separation, cooling, cleaning, control of the supply

Definitions

  • the invention relates to a liquid ring machine according to the preamble of claim 1 or 2.
  • Such a machine is known from DE-C-31 24 867. It is typical of this type of machine that the energy is transferred from the impeller to the pumped medium via a liquid ring formed from operating liquid. Since the operating fluid as an energy source and as a sealing element is in direct contact with the fluid, vapors are condensed, liquid and dirt particles are conveyed, hot gases are cooled and compression heat is absorbed by the operating fluid. If liquids are conveyed in the liquid ring, there is an increased power requirement and a deterioration in the running properties of the impeller, which can lead to accelerated wear of the impeller bearing.
  • a reduction in the power consumption and, at the same time, improved running properties with the conveyance of liquids is to be brought about in the known machine in that a relief passage which is separate from the pressure slot of the control disk is provided in the control body designed as a flat control disk. This discharge passage is covered by the rotating liquid ring when liquid is also conveyed. No further details on the function of the relief passage can be found in the cited patent.
  • a liquid ring pump is also known, in which a discharge opening is provided on the inner wall of the machine housing in the middle between the suction and pressure area of the machine.
  • This discharge opening opens into a line connected to the outer circumference of the machine housing.
  • This line runs up to the supply line for the operating fluid and is connected to it.
  • this line is provided with branches which open into sealing chambers formed in the side plates of the machine.
  • the arrangement of the discharge opening on the inner wall of the machine housing ensures that this opening is always swept by the operating fluid during operation and thus operating fluid is constantly drained through the discharge opening into the connected line.
  • This drained liquid which is under a certain pressure, is introduced via the branches into the sealing chambers and is used there to seal the gaps between the impeller and the machine housing. An excess amount of liquid not required for sealing is fed back into the supply line for the operating liquid as a result of the line being connected to the supply line.
  • the object of the invention is to provide a liquid ring machine in which the total amount of liquid resulting from the usual operating liquid and the additional liquid resulting from the respective process can be kept as constant as possible, so that an approximately uniform liquid ring thickness can be achieved.
  • a further solution to the problem is also achieved in accordance with the features of claim 2.
  • the increased amount of liquid as the liquid ring thickness increases is discharged outside the machine.
  • An increased liquid conveyance results in increased pressure conditions in the pressure range, so that an increased liquid outlet is brought about by the relief passage of the liquid ring machine. The pressure conditions that arise thus automatically regulate the liquid ring thickness.
  • connection between the relief passage and the operating fluid supply line, which runs outside the housing offers advantages in terms of accessibility and the cooling effect which can be achieved, whereas a connection located inside the housing has a compact design leads.
  • the connection can be provided either in the housing or outside the housing. The connection can thus be adapted to the respective operating and installation conditions.
  • connection between the relief passage and the operating fluid supply line is integrated in the side plate, there is no additional manufacturing effort for this connection.
  • passages and bores in the pressurized machine housing are eliminated, which can lead to a reduction in the strength of the machine housing.
  • Another advantage of this connection is that the excess operating fluid can flow off over a short connection path without further energy expenditure.
  • a control element controls the supply of the operating liquid as a function of the quantity of liquid flowing through the relief passage.
  • Hydraulic valves in particular ball valves or plate valves, are suitable as control elements.
  • Valves of this type are passive elements which control the supply of operating fluid without further control elements, solely on the basis of the pressure conditions which arise.
  • valves are accessible from the outside in their installed position, the valves can be adjusted according to the operating conditions. This also facilitates any maintenance work, for example due to operational pollution.
  • only one valve for controlling the liquid ring thickness is required.
  • the positioning of the valve causes the valve to release the connection leading to the relief passage to the extent that it simultaneously restricts the supply of operating fluid.
  • the liquid flowing out through the relief passage now supplements the operating liquid exactly by the proportion by which it has been reduced.
  • the liquid carried in the liquid ring therefore also leads to a reduction in the operating liquid requirement.
  • the machine can even be fed solely from the liquid flowing out through the relief passage.
  • the valve is fully open and at the same time largely prevents the supply of operating fluid.
  • connection between the relief passage and the operating fluid supply line does not require any significant additional manufacturing outlay, since the connection is made via at least one line channel provided in the side plate, which is already taken into account when casting the side plate.
  • the glands used to seal the shaft must be cooled due to the frictional load.
  • the liquid flowing out through the relief passage can, if a corresponding connection is provided, also be provided to relieve the stuffing box supply. In this way, the cooling of the stuffing boxes can be carried out entirely or additively by the liquid flowing out of the relief passage.
  • the path of a conveyed medium from a suction port 3 of the liquid ring machine 1 via its side plate 4 and the suction slot 5 of a control body embodied here as a flat control disk 6 in one of two blades 7 of the impeller is shown with bold arrows 2 8 and a co-rotating fluid ring marked impeller cell space. Due to the eccentric position of the impeller 8, the impeller cell space changes its size continuously during one revolution of the impeller 8. As a result of the reduction in the impeller cell space in the pressure-side control disc area 15, the pumped medium is compressed and pushed out via a pressure slot 9 in the control disc 6. The pumped medium compressed in this way then flows out through a pressure connection 10.
  • operating fluid 11 must be continuously supplied via an operating fluid supply line.
  • the operating fluid reaches the suction-side control disk area 14 of the liquid ring machine 1 via a channel system in the hub area 12 and corresponding passages 13 in the control disk 6.
  • the excess operating liquid 20 is pushed out through a relief passage 16 located in the pressure-side control disc area 15 and is fed via a connecting line 17, which is integrated in the side plate 4, to the operating liquid supply line 11 also located in the side plate 4.
  • a connecting line 17 which is integrated in the side plate 4
  • This avoids an increase in the liquid ring thickness and thus any over-compression of the pumped medium.
  • This also eliminates other disadvantages already mentioned, such as increased energy consumption and impaired running smoothness.
  • the ball valve 18 is closed.
  • the ball 22 of the ball valve 18 closes, under the influence of a spring 23, the connecting line 17 leading away from the relief passage.
  • the ball 22 is pressed into the mouth by the spring 23, which is supported on the wall opposite the opening of the connecting line 17.
  • the ball valve 18 does not impede the entry of operating fluid from outside the machine 1, for example from a storage container (not shown in the drawing).
  • FIG 4 finally shows the case of a strong suction-side liquid conveyance.
  • the ball valve 18 is fully open.
  • the excess fluid 20 flowing out through the relief passage 16 flows almost unhindered into the operating fluid supply line 11 and / or into the operating fluid reservoir outside the fluid ring machine 1. No more operating fluid 21 is sucked in.
  • the process water supply is carried out solely from the liquid to be conveyed that is produced on the suction side.
  • FIGS. 5-7 A control with a plate valve 19 analogous to the control with a ball valve 18 is shown in FIGS. 5-7.
  • 5 shows a closed plate valve 19 for the operating case without liquid-side conveyance on the suction side.
  • the connecting line 17 is closed, whereas the supply of operating fluid is unimpeded.
  • 6, the plate valve 19 is partially open.
  • the portion of the self-sucked-in operating liquid 21 is reduced in favor of the excess liquid 20 flowing out of the relief passage 16 due to the narrowing of the cross-section in the operating liquid supply line 11.
  • the amount of operating fluid supplied in the hub area 12 thus does not change, so that the liquid ring thickness remains almost constant despite the liquid being conveyed.
  • the plate valve 19 is fully open.
  • the excess liquid 20, which flows out of the connecting line 17, serves for the exclusive supply of operating liquid to the liquid ring machine 1.
  • a quantity of liquid which exceeds the requirement for operating liquid can be discharged into a storage container located outside the liquid ring machine 1.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)
  • Acyclic And Carbocyclic Compounds In Medicinal Compositions (AREA)
  • Details And Applications Of Rotary Liquid Pumps (AREA)

Abstract

When liquids are conveyed together in the liquid ring of a liquid ring machine (1), there results an increased power requirement and a deterioration of the running characteristics of the rotor (8). A liquid ring machine (1) for selectively conveying several liquids has a housing (3) which eccentrically surrounds a rotor (8) and whose end face is closed by lateral shields (4) for the rotor shaft. At least one controlling body provided with a suction and delivery slot (9) is associated with the rotor (8) and has a relief passage (16), additional to the delivery slot (9) located in the delivery area. In order to obtain a liquid ring having an approximately constant thickness, the relief passage (16) is directly connected to the working liquid supply line of the liquid ring machine (1) so that excess liquid (20) flowing out through the relief passage (16) is added directly to the working liquid (21).

Description

Die Erfindung betrifft eine Flüssigkeitsringmaschine gemäß dem Oberbegriff des Anspruchs 1 oder 2.The invention relates to a liquid ring machine according to the preamble of claim 1 or 2.

Eine solche Maschine ist aus der DE-C-31 24 867 bekannt. Typisch für diese Maschinenart ist, daß die Energie vom Laufrad über einen aus Betriebsflüssigkeit gebildeten Flüssigkeitsring auf das Fördermedium übertragen wird. Da die Betriebsflüssigkeit als Energieträger und als abdichtendes Element unmittelbar mit dem Fördermedium direkt in Kontakt steht, werden Dämpfe kondensiert, Flüssigkeits- und Schmutzteilchen mitgefördert, heiße Gase abgekühlt und Kompressionswärme von der Betriebsflüssigkeit aufgenommen. Bei einer etwaigen Mitförderung von Flüssigkeiten im Flüssigkeitsring ergibt sich ein erhöhter Leistungsbedarf und eine Verschlechterung der Laufeigenschaften des Laufrades, die zu einer beschleunigten Abnutzung der Laufradlagerung führen können.Such a machine is known from DE-C-31 24 867. It is typical of this type of machine that the energy is transferred from the impeller to the pumped medium via a liquid ring formed from operating liquid. Since the operating fluid as an energy source and as a sealing element is in direct contact with the fluid, vapors are condensed, liquid and dirt particles are conveyed, hot gases are cooled and compression heat is absorbed by the operating fluid. If liquids are conveyed in the liquid ring, there is an increased power requirement and a deterioration in the running properties of the impeller, which can lead to accelerated wear of the impeller bearing.

Eine Verringerung der Leistungsaufnahme, bei gleichzeitig verbesserten Laufeigenschaften bei Mitförderung von Flüssigkeiten soll bei der bekannten Maschine dadurch bewirkt werden, daß in dem als ebene Steuerscheibe ausgebildeten Steuerkörper ein vom Druckschlitz der Steuerscheibe getrennter Entlastungsdurchlaß vorgesehen ist. Dieser Entlastungsdurchlaß wird bei Mitförderung von Flüssigkeit vom rotierenden Flüssigkeitsring überdeckt. Weitere Ausführungen über die Funktion des Entlastungsdurchlasses sind der genannten Patentschrift nicht entnehmbar.A reduction in the power consumption and, at the same time, improved running properties with the conveyance of liquids is to be brought about in the known machine in that a relief passage which is separate from the pressure slot of the control disk is provided in the control body designed as a flat control disk. This discharge passage is covered by the rotating liquid ring when liquid is also conveyed. No further details on the function of the relief passage can be found in the cited patent.

Durch die DE-A-15 03 586 ist ferner eine Flüssigkeitsringpumpe bekannt, bei der an der Innenwand des Maschinengehäuses mittig zwischen dem Ansaug- und Druckbereich der Maschine eine Ableitöffnung vorgesehen ist. Diese Ableitöffnung mündet in eine am Außenumfang des Maschinengehäuses angeschlossene Leitung. Diese Leitung ist bis zu der Zuleitung für die Betriebsflüssigkeit geführt und an diese angeschlossen. Ferner ist diese Leitung mit Abzweigen versehen, die in in den Seitenschilden der Maschine ausgebidlete Dichtkammern münden.From DE-A-15 03 586 a liquid ring pump is also known, in which a discharge opening is provided on the inner wall of the machine housing in the middle between the suction and pressure area of the machine. This discharge opening opens into a line connected to the outer circumference of the machine housing. This line runs up to the supply line for the operating fluid and is connected to it. Furthermore, this line is provided with branches which open into sealing chambers formed in the side plates of the machine.

Durch die Anordnung der Ableitöffnung an der Innenwand des Maschinengehäuses ist sichergestellt, daß diese Öffnung während des Betriebes stets von der Betriebsflüssigkeit überstrichen wird und somit ständig Betriebsflüssigkeit über die Ableitöffnung in die angeschlossene Leitung abgeleitet wird. Diese abgeleitete Flüssigkeit, die unter einem bestimmten Druck steht, wird über die Abzweige in die Dichtungskammern eingeleitet und dient dort zum Abdichten der zwischen dem Laufrad und dem Maschinengehäuse bestehende Spalte. Eine nicht zum Abdichten benötigte, überschüssige Flüssigkeitsmenge wird infolge des Anschlusses der Leitung an die Zuleitung für die Betriebsflüssigkeit dieser wieder zugeführt.The arrangement of the discharge opening on the inner wall of the machine housing ensures that this opening is always swept by the operating fluid during operation and thus operating fluid is constantly drained through the discharge opening into the connected line. This drained liquid, which is under a certain pressure, is introduced via the branches into the sealing chambers and is used there to seal the gaps between the impeller and the machine housing. An excess amount of liquid not required for sealing is fed back into the supply line for the operating liquid as a result of the line being connected to the supply line.

Aufgabe der Erfindung ist es, eine Flüssigkeitsringmaschine zu schaffen, bei der die sich aus der üblichen Betriebsflüssigkeit und der aus dem jeweiligen Prozeß anfallenden Zusatzflüssigkeit ergebende Gesamtmenge an Flüssigkeit möglichst konstant gehalten werden kann, so daß eine annähernd gleichmäßige Flüssigkeitsringdicke erzielbar ist.The object of the invention is to provide a liquid ring machine in which the total amount of liquid resulting from the usual operating liquid and the additional liquid resulting from the respective process can be kept as constant as possible, so that an approximately uniform liquid ring thickness can be achieved.

Eine Lösung der gestellten Aufgabe gelingt durch die in Anspruch 1 genannten Merkmale. Im Falle einer Flüssigkeitsmitförderung wächst die Flüssigkeitsringdicke an und damit die durch den Entlastungsdurchlaß austretende Flüssigkeitsmenge. Diese Flüssigkeit wird unmittelbar der Betriebsflüssigkeit zugeführt. Hiermit ist eine Reduzierung des Betriebsflüssigkeitsbedarfes gegeben. Ein Anwachsen der Flüssigkeitsringdicke infolge von Flüssigkeitsmitförderung führt demnach automatisch zu einer Drosselung der Betriebsflüssigkeitszufuhr.A solution to the problem is achieved by the features mentioned in claim 1. In the case of liquid conveyance, the liquid ring thickness increases and thus the amount of liquid escaping through the relief passage. This liquid is fed directly to the operating liquid. This reduces the operating fluid requirement. An increase in the liquid ring thickness as a result of liquid conveyance accordingly automatically leads to a restriction of the operating liquid supply.

Eine weitere Lösung der gestellten Aufgabe gelingt auch gemäß den Merkmalen des Anspruches 2. Hierbei wird die bei Anwachsen der Flüssigkeitsringdicke vermehrte Flüssigkeitsmenge nach außerhalb der Maschine abgeführt. Eine erhöhte Flüssigkeitsmitförderung hat erhöhte Druckverhältnisse im Druckbereich zur Folge, so daß ein verstärkter Flüssigkeitsaustritt durch den Entlastungsdurchlaß der Flüssigkeitsringmaschine bewirkt wird. Die sich einstellenden Druckverhältnisse regeln somit selbsttätig die Flüssigkeitsringdicke.A further solution to the problem is also achieved in accordance with the features of claim 2. Here, the increased amount of liquid as the liquid ring thickness increases is discharged outside the machine. An increased liquid conveyance results in increased pressure conditions in the pressure range, so that an increased liquid outlet is brought about by the relief passage of the liquid ring machine. The pressure conditions that arise thus automatically regulate the liquid ring thickness.

Eine Verbindung zwischen Entlastungsdurchlaß und Betriebsflüssigkeitszuleitung, die außerhalb des Gehäuses veriäuft, bietet hinsichtlich der Zugänglichkeit und des erzielbaren Kühleffektes Vorteile, wohingegen eine innerhalb des Gehäuses befindliche Verbindung zu einer kompakten Bauweise führt. Gemäß einer Ausgestaltung der Erfindung kann die Verbindung entweder im Gehäuse oder außerhalb des Gehäuses vorgesehen werden. Die Verbindung kann somit den jeweiligen Betriebs- und Einbauverhältnissen angepaßt werden.A connection between the relief passage and the operating fluid supply line, which runs outside the housing, offers advantages in terms of accessibility and the cooling effect which can be achieved, whereas a connection located inside the housing has a compact design leads. According to one embodiment of the invention, the connection can be provided either in the housing or outside the housing. The connection can thus be adapted to the respective operating and installation conditions.

Dadurch, daß die Verbindung zwischen Entlastungsdurchlaß und Betriebsflüssigkeitszuleitung im Seitenschild integriert ist, entsteht kein zusätzlicher Fertigungsaufwand für diese Verbindung. Außerdem entfallen Durchlässe und Bohrungen in dem druckbelasteten Maschinengehäuse, die zu einer Verminderung der Festigkeit des Maschinengehäuses führen können. Ein weiterer Vorteil dieser Verbindung ist, daß die überschüssige Betriebsflüssigkeit ohne weiteren Energieaufwand über einen kurzen Verbindungsweg abfließen kann.Because the connection between the relief passage and the operating fluid supply line is integrated in the side plate, there is no additional manufacturing effort for this connection. In addition, passages and bores in the pressurized machine housing are eliminated, which can lead to a reduction in the strength of the machine housing. Another advantage of this connection is that the excess operating fluid can flow off over a short connection path without further energy expenditure.

Ein Konstanthalten der in der Flüssigkeitsringmaschine rotierenden Flüssigkeit wird dadurch erreicht, daß ein Steuerglied in Abhängigkeit von der durch den Entlastungsdurchlaß abfließenden Flüssigkeitsmenge die Zuführung der Betriebsflüssigkeit steuert.Keeping the liquid rotating in the liquid ring machine constant is achieved in that a control element controls the supply of the operating liquid as a function of the quantity of liquid flowing through the relief passage.

Als Steuerglieder eignen sich hydraulische Ventile, insbesondere Kugelventile oder Plattenventile. Derartige Ventile stellen passive Elemente dar, die ohne weitere Steuerelemente, allein aufgrund der sich einstellenden Druckverhältnisse die Betriebsflüssigkeitszufuhr steuern.Hydraulic valves, in particular ball valves or plate valves, are suitable as control elements. Valves of this type are passive elements which control the supply of operating fluid without further control elements, solely on the basis of the pressure conditions which arise.

Dadurch, daß die Ventile in ihrer Einbaulage von außen zugänglich sind, kann eine den Betriebsverhältnissen entsprechende Einstellung der Ventile vorgenommen werden. Etwaige Wartungsarbeiten, beispielsweise infolge von betriebsbedingter Verschmutzung, sind hierdurch ebenfalls erleichtert.Because the valves are accessible from the outside in their installed position, the valves can be adjusted according to the operating conditions. This also facilitates any maintenance work, for example due to operational pollution.

Nach einer weiteren Ausgestaltung der Erfindung gemäß Anspruch 8 wird nur ein Ventil zur Steuerung der Flüssigkeitsringdicke benötigt. Die Positionierung des Ventiles bewirkt, daß das Ventil die zum Entlastungsdurchlaß führende Verbindung in dem Maße freigibt, wie es die Betriebsflüssigkeitszufuhr gleichzeitig drosselt. Die durch den Entlastungsdurchlaß ausströmende Flüssigkeit ergänzt nun die Betriebsflüssigkeit genau um den Anteil, um den sie reduziert wurde. Die im Flüssigkeitsring mitgeführte Flüssigkeit führt demnach auch zu einer Verringerung des Betriebsflüssigkeitsbedarfes. Im äußersten Falle kann die Maschine sogar allein aus der durch den Entlastungsdurchlaß ausströmenden Flüssigkeit gespeist werden. In diesem Falle ist das Ventil ganz geöffnet und damit gleichzeitig die Betriebsflüssigkeitszufuhr weitestgehend unterbunden.According to a further embodiment of the invention, only one valve for controlling the liquid ring thickness is required. The positioning of the valve causes the valve to release the connection leading to the relief passage to the extent that it simultaneously restricts the supply of operating fluid. The liquid flowing out through the relief passage now supplements the operating liquid exactly by the proportion by which it has been reduced. The liquid carried in the liquid ring therefore also leads to a reduction in the operating liquid requirement. In the extreme case, the machine can even be fed solely from the liquid flowing out through the relief passage. In this case, the valve is fully open and at the same time largely prevents the supply of operating fluid.

Die Verbindung zwischen Entlastungsdurchlaß und Betriebsflüssigkeitszuleitung erfordert keinen nennenswerten zusätzlichen Herstellungsaufwand, da die Verbindung über wenigstens einen im Seitenschild vorgesehenen Leitungskanal erfolgt, der bereits beim Gießen des Seitenschildes berücksichtigt ist.The connection between the relief passage and the operating fluid supply line does not require any significant additional manufacturing outlay, since the connection is made via at least one line channel provided in the side plate, which is already taken into account when casting the side plate.

Die zur Wellenabdichtung dienenden Stopfbuchsen müssen infolge der reibenden Beanspruchung gekühlt werden. Die durch den Entlastungsdurchlaß ausströmende Flüssigkeit kann, sofern eine entsprechende Verbindung vorgesehen ist, auch zur Entlastung der Stopfbuchsversorgung vorgesehen werden. Damit kann die Kühlung der Stopfbuchsen zur Gänze oder additiv von der aus dem Entlastungsdurchlaß ausströmenden Flüssigkeit übernommen werden.The glands used to seal the shaft must be cooled due to the frictional load. The liquid flowing out through the relief passage can, if a corresponding connection is provided, also be provided to relieve the stuffing box supply. In this way, the cooling of the stuffing boxes can be carried out entirely or additively by the liquid flowing out of the relief passage.

Zwei Ausführungsbeispiele einer erfindungsgemäßen Flüssigkeitsringmaschine werden anhand der nachfolgenden Zeichnung näher erläutert. Es zeigt:

FIG 1
eine Flüssigkeitsringmschine in explodierter Darstellung
FIG 2
eine Draufsicht auf ein Seitenschild einer Flüssigkeitsringmaschine mit einem als Kugelventil ausgebildeten Steuerglied in Schließstellung
FIG 3
eine Draufsicht auf eine Teilansicht des Seitenschildes einer Flüssigkeitsringmaschine mit einem als Kugelventil ausgebildeten Steuerglied in teilweise geöffneter Stellung
FIG 4
eine Draufsicht auf eine Teilansicht des Seitenschildes einer Flüssigkeitsringmaschine mit einem als Kugelventil ausgebildeten Steuerglied in voller Öffnungsstellung
FIG 5
eine Draufsicht auf eine Teilansicht des Seitenschildes mit einem als Plattenventil ausgebildeten Steuerglied in Schließstellung
FIG 6
eine Draufsicht auf eine Teilansicht des Seitenschildes mit einem als Plattenventil ausgebildeten Steuerglied in teilweise geöffneter Stellung und
FIG 7
eine Draufsicht auf eine Teilansicht des Seitenschildes mit einem als Plattenventil ausgebildeten Steuerglied in voller Öffnungsstellung.
Two embodiments of a liquid ring machine according to the invention are explained in more detail with reference to the following drawing. It shows:
FIG. 1
a liquid ring machine in an exploded view
FIG 2
a plan view of a side plate of a liquid ring machine with a control element designed as a ball valve in the closed position
FIG 3
a plan view of a partial view of the side plate of a liquid ring machine with a control element designed as a ball valve in a partially open position
FIG 4
a plan view of a partial view of the side plate of a liquid ring machine with a control element designed as a ball valve in the fully open position
FIG 5
a plan view of a partial view of the side plate with a control member designed as a plate valve in the closed position
FIG 6
a plan view of a partial view of the side plate with a control member designed as a plate valve in a partially open position and
FIG 7
a plan view of a partial view of the side plate with a control element designed as a plate valve in the fully open position.

Bei der in FIG 1 dargestellten Flüssigkeitsringmaschine 1 ist mit fett eingetragenen Pfeilen 2 der Weg eines Fördermediums von einem Saugstutzen 3 der Flüssigkeitsringmaschine 1 über deren Seitenschild 4 und den Saugschlitz 5 eines hier als ebene Steuerscheibe 6 ausgeführten Steuerkörpers in einen von jeweils zwei Schaufeln 7 des Laufrades 8 und einem mitrotierenden Flüssigkeitsring umgrenzten Laufradzellenraum markiert. Aufgrund der exzentrischen Lage des Laufrades 8 verändert der Laufradzellenraum während einer Umdrehung des Laufrades 8 fortwährend seine Größe. Infolge der im druckseitigen Steuerscheibenbereich 15 erfolgenden Verkleinerung des Laufradzellenraumes wird das Fördermedium verdichtet und über einen in der Steuerscheibe 6 befindlichen Druckschlitz 9 ausgeschoben. Das so verdichtete Fördermedium strömt dann durch einen Druckstutzen 10 aus. Betriebsbedingt wird mit dem Fördermedium auch ein Teil der zum Aufbau des Flüssigkeitsringes benötigten Betriebsflüssigkeit mit ausgestoßen. Deshalb muß fortwährend über eine Betriebsflüssigkeitszuleitung 11 Betriebsflüssigkeit zugeführt werden. Die Betriebsflüssigkeit gelangt über ein Kanalsystem im Nabenbereich 12 und entsprechende Durchlässe 13 in der Steuerscheibe 6 in den saugseitigen Steuerscheibenbereich 14 der Flüssigkeitsringmaschine 1.In the liquid ring machine 1 shown in FIG. 1, the path of a conveyed medium from a suction port 3 of the liquid ring machine 1 via its side plate 4 and the suction slot 5 of a control body embodied here as a flat control disk 6 in one of two blades 7 of the impeller is shown with bold arrows 2 8 and a co-rotating fluid ring marked impeller cell space. Due to the eccentric position of the impeller 8, the impeller cell space changes its size continuously during one revolution of the impeller 8. As a result of the reduction in the impeller cell space in the pressure-side control disc area 15, the pumped medium is compressed and pushed out via a pressure slot 9 in the control disc 6. The pumped medium compressed in this way then flows out through a pressure connection 10. For operational reasons, part of the operating liquid required to build up the liquid ring is also expelled with the pumped medium. Therefore, operating fluid 11 must be continuously supplied via an operating fluid supply line. The operating fluid reaches the suction-side control disk area 14 of the liquid ring machine 1 via a channel system in the hub area 12 and corresponding passages 13 in the control disk 6.

Im Falle einer Flüssigkeitsmitförderung wird die überschüssige Betriebsflüssigkeit 20 durch einen im druckseitigen Steuerscheibenbereich 15 befindlichen Entlastungsdurchlaß 16 ausgeschoben und über eine Verbindungsleitung 17, die im Seitenschild 4 integriert ist, der ebenfalls im Seitenschild 4 befindlichen Betriebsflüssigkeitszuleitung 11 zugeführt. Dadurch wird ein Anwachsen der Flüssigkeitsringdicke und damit eine etwaige Überkomprimierung des Fördermediums vermieden. Auch weitere schon genannte Nachteile, wie ein erhöhter Energiebedarf und eine Beeinträchtigung der Laufruhe, sind so beseitigt.In the case of liquid conveyance, the excess operating liquid 20 is pushed out through a relief passage 16 located in the pressure-side control disc area 15 and is fed via a connecting line 17, which is integrated in the side plate 4, to the operating liquid supply line 11 also located in the side plate 4. This avoids an increase in the liquid ring thickness and thus any over-compression of the pumped medium. This also eliminates other disadvantages already mentioned, such as increased energy consumption and impaired running smoothness.

In den FIG 2 bis 4 wird gezeigt, in welcher Weise die Steuerung der Betriebsflüssigkeitszufuhr in Abhängigkeit von der durch den Entlastungsdurchlaß 16 ausströmenden überschüssigen Flüssigkeit 20 erfolgt. An der Mündungsstelle der vom Entlastungsdurchlaß 16 zur Betriebsflüssigkeitszuleitung 11 führenden Verbindung in die Betriebsflüssigkeitszuleitung 11 ist ein Kugelventil 18 so eingebaut, daß es beide Flüssigkeitswege beeinflußt.2 to 4 show the manner in which the control of the operating fluid supply is dependent of the excess liquid 20 flowing out through the relief passage 16. At the mouth of the connection leading from the relief passage 16 to the operating fluid supply line 11 into the operating fluid supply line 11, a ball valve 18 is installed in such a way that it influences both fluid paths.

In FIG 2 ist das Kugelventil 18 geschlossen. Die Kugel 22 des Kugelventils 18 verschließt unter dem Einfluß einer Feder 23 die vom Entlastungsdurchlaß wegführende Verbindungsleitung 17. Die Kugel 22 wird von der Feder 23, die sich an der der Mündung der Verbindungsleitung 17 gegenüberliegenden Wand abstützt in die Mündung gedrückt. Hierdurch gelangt über die Verbindungsleitung 17 keine Flüssigkeit in die Betriebsflüssigkeitszuleitung 11. Etwaig ausströmende überschüssige Flüssigkeit 20 wird bei dieser Ventilstellung in der Verbindungsleitung 17 zurückgehalten. Der Betriebsflüssigkeitseintritt von außerhalb der Maschine 1, beispielsweise aus einem in der Zeichnung nicht dargestellten Vorratsbehälter, wird durch das Kugelventil 18 nicht behindert.2, the ball valve 18 is closed. The ball 22 of the ball valve 18 closes, under the influence of a spring 23, the connecting line 17 leading away from the relief passage. The ball 22 is pressed into the mouth by the spring 23, which is supported on the wall opposite the opening of the connecting line 17. As a result, no liquid gets into the operating liquid supply line 11 via the connecting line 17. Any excess liquid 20 that flows out is retained in the connecting line 17 in this valve position. The ball valve 18 does not impede the entry of operating fluid from outside the machine 1, for example from a storage container (not shown in the drawing).

In dem in FIG 3 gezeigten Betriebszustand der Flüssigkeitsringmaschine 1 wird saugseitig Flüssigkeit mitgefördert. Es strömt verstärkt überschüssige Flüssigkeit durch den Entlastungsdurchlaß 16 in die Verbindungsleitung 17. Das Kugelventil 18 ist infolge des anstehenden hydraulischen Drucks teilweise geöffnet. Hierdurch wird der Flüssigkeitsweg für die in der Verbindungsleitung 17 anstehende überschüssige Flüssigkeit 20 teilweise freigegeben. Gleichzeitig wird der Betriebsflüssigkeitseintritt von außerhalb der Maschine 1 durch das teilweise geöffnete Kugelventil 18 und die hierdurch bewirkte Querschnittsverengung der Betriebsflüssigkeitszuleitung 11 behindert.In the operating state of the liquid ring machine 1 shown in FIG. 3, liquid is also conveyed on the suction side. Excess liquid flows increasingly through the relief passage 16 into the connecting line 17. The ball valve 18 is partially open due to the hydraulic pressure present. This partially clears the liquid path for the excess liquid 20 present in the connecting line 17. At the same time, the operating fluid entry from outside the machine 1 is impeded by the partially open ball valve 18 and the cross-sectional narrowing of the operating fluid supply line 11 caused thereby.

Damit wird eine Reduktion der selbstangesaugten Betriebsflüssigkeit 21 bewirkt. Die aus dem Entlastungsdurchlaß 16 ausströmende überschüssige Flüssigkeit 20 ersetzt diese eingesparte Betriebsflüssigkeit 21.This results in a reduction in the self-sucked-in operating fluid 21. The excess liquid 20 flowing out of the relief passage 16 replaces this saved operating liquid 21.

FIG 4 zeigt schließlich den Fall einer starken saugseitigen Flüssigkeitsmitförderung. In diesem Fall ist das Kugelventil 18 voll geöffnet. Die durch den Entlastungsdurchlaß 16 ausströmende überschüssige Flüssigkeit 20 strömt nahezu ungehindert in die Betriebsflüssigkeitszuleitung 11 und/oder in den Betriebsflüssigkeitsvorratsbehälter außerhalb der Flüssigkeitsringmaschine 1. Es wird keine Betriebsflüssigkeit 21 mehr angesaugt. In diesem Falle erfolgt demnach die Betriebswasserversorgung allein aus der saugseitig anfallenden mitzufördernden Flüssigkeit.FIG 4 finally shows the case of a strong suction-side liquid conveyance. In this case, the ball valve 18 is fully open. The excess fluid 20 flowing out through the relief passage 16 flows almost unhindered into the operating fluid supply line 11 and / or into the operating fluid reservoir outside the fluid ring machine 1. No more operating fluid 21 is sucked in. In this case, the process water supply is carried out solely from the liquid to be conveyed that is produced on the suction side.

Eine zu der Steuerung mit einem Kugelventil 18 analoge Steuerung mit einem Plattenventil 19 ist in den FIG 5 - 7 gezeigt. FIG 5 zeigt ein geschlossenes Plattenventil 19 für den Betriebsfall ohne saugseitige Flüssigkeitsmitförderung. Die Verbindungsleitung 17 ist verschlossen, wohingegen die Betriebsflüssigkeitszufuhr ungehindert ist. In FIG 6 ist das Plattenventil 19 teilweise geöffnet. Auch hier wird durch die bewirkte Querschnittsverengung in der Betriebsflüssigkeitszuleitung 11 der Anteil der selbstangesaugten Betriebsflüssigkeit 21 zugunsten der aus dem Entlastungsdurchlaß 16 ausströmenden überschüssigen Flüssigkeit 20 reduziert. Die im Nabenbereich 12 zugeführte Betriebsflüssigkeitsmenge ändert sich somit nicht, so daß trotz der Flüssigkeitsmitförderung die Flüssigkeitsringdicke nahezu konstant bleibt. In der Darstellung nach FIG 7, die für den Fall einer starken saugseitigen Flüssigkeitsmitförderung gilt, ist das Plattenventil 19 voll geöffnet. Die überschüssige Flüssigkeit 20, die aus der Verbindungsleitung 17 ausströmt, dient zur ausschließlichen Betriebsflüssigkeitsversorgung der Flüssigkeitsringmaschine 1. Eine über den Bedarf an Betriebsflüssigkeit hinausgehende Flüssigkeitsmenge kann in einen außerhalb der Flüssigkeitsringmaschine 1 befindlichen Vorratsbehälter abgeführt werden.A control with a plate valve 19 analogous to the control with a ball valve 18 is shown in FIGS. 5-7. 5 shows a closed plate valve 19 for the operating case without liquid-side conveyance on the suction side. The connecting line 17 is closed, whereas the supply of operating fluid is unimpeded. 6, the plate valve 19 is partially open. Here too the portion of the self-sucked-in operating liquid 21 is reduced in favor of the excess liquid 20 flowing out of the relief passage 16 due to the narrowing of the cross-section in the operating liquid supply line 11. The amount of operating fluid supplied in the hub area 12 thus does not change, so that the liquid ring thickness remains almost constant despite the liquid being conveyed. In the illustration according to FIG. 7, which in the case of strong suction-side liquid conveyance applies, the plate valve 19 is fully open. The excess liquid 20, which flows out of the connecting line 17, serves for the exclusive supply of operating liquid to the liquid ring machine 1. A quantity of liquid which exceeds the requirement for operating liquid can be discharged into a storage container located outside the liquid ring machine 1.

Claims (10)

  1. Liquid ring machine (1) for selective entrainment of liquids, having a machine housing which eccentrically surrounds an impeller (8) and is closed off on the end face by lateral shields (4) for the impeller shaft, and in which machine (1) at least one control body (6), which is provided with a suction and delivery slit (8, 9), is allocated to the impeller (8), which control body has in its delivery-side region (15), in addition to the delivery slit (9), at least one discharge passage (16), characterised in that the discharge passage (16) is directly connected to the operating-liquid supply line (11) of the liquid ring machine (1) and excess liquid (20) exiting through the discharge passage (16) is supplied directly to the operating liquid (21).
  2. Liquid ring machine (1) for selective entrainment of liquids, having a machine housing which eccentrically surrounds an impeller (8) and is closed off on the end face by lateral shields (4) for the impeller shaft, in which machine (1) at least one control body, which is provided with a suction and delivery slit (8, 9), is allocated to the impeller (8), which control body (6) has in its delivery-side region (15), in addition to the delivery slit (9), at least one discharge passage (16), characterised in that the discharge passage (16) is connected to a closed lead-off line which opens out outside the machine housing.
  3. Liquid ring machine according to claim 1, characterised in that the connection between discharge passage (16) and operating-liquid supply line (11) is provided either in the housing or outside the housing.
  4. Liquid ring machine (1) according to claim 3, characterised in that the connection between discharge passage (16) and operating-liquid supply line (11) is integrated in the lateral shield (4).
  5. Liquid ring machine (1) according to one or more of the preceding claims, characterised in that a control member is provided, by means of which the amount of the operating liquid (21) supplied is controlled as a function of the liquid amount which flows off through the discharge passage (16).
  6. Liquid ring machine (1) according to claim 5, characterised in that a hydraulic valve or a ball valve (18) or a plate valve (19) is provided as a control member.
  7. Liquid ring machine (1) according to claim 5 and/or 6, characterised in that the valve, in its installation position, is accessible from the outside.
  8. Liquid ring machine (1) according to one or more of the claims 5 to 7, characterised in that the respective valve at the place at which the connection coming from the discharge passage opens out into the operating-liquid supply line (1) (sic) is installed in such a way that the valve influences simultaneously the flow resistance of both liquid paths.
  9. Liquid ring machine (1) according to one or more of the preceding claims, characterised in that the connection between discharge passage (16) and the operating-liquid supply line (11) takes place by way of at least one line duct provided in the lateral shield (4).
  10. Liquid ring machine (1) according to one or more of the preceding claims, characterised in that an additional connection is provided between the discharge passage (16) and the stuffing box located in the bearing shield (4).
EP94904567A 1993-01-25 1994-01-11 Liquid ring machine Expired - Lifetime EP0680562B1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE4301907A DE4301907A1 (en) 1993-01-25 1993-01-25 Liquid ring machine
DE4301907 1993-01-25
PCT/DE1994/000021 WO1994017309A1 (en) 1993-01-25 1994-01-11 Liquid ring machine

Publications (2)

Publication Number Publication Date
EP0680562A1 EP0680562A1 (en) 1995-11-08
EP0680562B1 true EP0680562B1 (en) 1997-04-02

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EP94904567A Expired - Lifetime EP0680562B1 (en) 1993-01-25 1994-01-11 Liquid ring machine

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US (1) US5605445A (en)
EP (1) EP0680562B1 (en)
JP (1) JPH08505679A (en)
BR (1) BR9406221A (en)
CA (1) CA2154476A1 (en)
DE (2) DE4301907A1 (en)
FI (1) FI953540A (en)
WO (1) WO1994017309A1 (en)

Families Citing this family (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19758340A1 (en) * 1997-12-22 1999-07-08 Gardner Denver Wittig Gmbh Multi-flow liquid ring pump
DE19819538C2 (en) 1998-04-30 2000-02-17 Rietschle Werner Gmbh & Co Kg Pressure suction pump
DE20016016U1 (en) * 2000-09-15 2002-01-31 Speck-Pumpenfabrik Walter Speck GmbH & Co. KG, 91154 Roth Control cover for a liquid ring pump and pump provided with such a control cover
US20040202549A1 (en) * 2003-01-17 2004-10-14 Barton Russell H. Liquid ring pump
GB0321455D0 (en) * 2003-09-12 2003-10-15 Aesseal Plc Self regulating re-circulation system for use with vacuum pumps
WO2006059577A1 (en) * 2004-12-01 2006-06-08 Nippon Sheet Glass Company, Limited Glass production apparatus and process for producing glass
DE102005043434A1 (en) * 2005-09-13 2007-03-15 Gardner Denver Elmo Technology Gmbh Device for adjusting the capacity of a liquid ring pump
EP1855010B1 (en) * 2006-05-11 2008-08-13 Pompetravaini S.p.A. Single-stage liquid ring vacuum pump with suction and discharge manifold integrated in the central body.
BRPI0823340A2 (en) 2008-12-18 2015-06-23 Gardner Denver Nash Llc Liquid annular pump with gas elimination device
US9689387B2 (en) * 2012-10-30 2017-06-27 Gardner Denver Nash, Llc Port plate of a flat sided liquid ring pump having a gas scavenge passage therein
CN114810597B (en) * 2022-05-11 2023-02-03 广东锦坤实业有限公司 High-efficient vacuum system that freezes of fatty acid processing

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US1904321A (en) * 1931-06-01 1933-04-18 Nash Engineering Co Hydroturbine pumping apparatus
DE675378C (en) * 1936-02-29 1939-05-06 Nash Engineering Co Liquid ring pump
BE664205A (en) * 1964-05-20
GB1509661A (en) * 1976-02-11 1978-05-04 Grayden Pty Ltd P Water ring vacuum pumps
DE3124867C2 (en) * 1981-06-24 1983-11-17 Siemens AG, 1000 Berlin und 8000 München Liquid ring vacuum pump for gaseous media
DE3617344A1 (en) * 1986-05-23 1987-11-26 Siemens Ag METHOD FOR PRODUCING A CONTROL DISC OR A CONTROL SHIELD FOR A LIQUID RING MACHINE FOR MORE AGGRESSIVE MEDIA

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Publication number Publication date
CA2154476A1 (en) 1994-08-04
EP0680562A1 (en) 1995-11-08
FI953540A0 (en) 1995-07-24
DE59402303D1 (en) 1997-05-07
US5605445A (en) 1997-02-25
BR9406221A (en) 1996-01-09
WO1994017309A1 (en) 1994-08-04
FI953540A (en) 1995-07-24
DE4301907A1 (en) 1994-07-28
JPH08505679A (en) 1996-06-18

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