EP0045483B1 - Self-priming rotary pump, particularly for bringing liquids to their boiling point - Google Patents

Self-priming rotary pump, particularly for bringing liquids to their boiling point Download PDF

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Publication number
EP0045483B1
EP0045483B1 EP81105972A EP81105972A EP0045483B1 EP 0045483 B1 EP0045483 B1 EP 0045483B1 EP 81105972 A EP81105972 A EP 81105972A EP 81105972 A EP81105972 A EP 81105972A EP 0045483 B1 EP0045483 B1 EP 0045483B1
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EP
European Patent Office
Prior art keywords
centrifugal pump
stage
supply chamber
fluid supply
pump
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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
Application number
EP81105972A
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German (de)
French (fr)
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EP0045483A3 (en
EP0045483A2 (en
Inventor
Wilfried Dr. Ing. Lehmann
Peter Ing.-Grad Fandrey
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Sihi GmbH and Co KG
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Sihi GmbH and Co KG
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Priority to AT81105972T priority Critical patent/ATE5433T1/en
Publication of EP0045483A2 publication Critical patent/EP0045483A2/en
Publication of EP0045483A3 publication Critical patent/EP0045483A3/en
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Publication of EP0045483B1 publication Critical patent/EP0045483B1/en
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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D9/00—Priming; Preventing vapour lock
    • F04D9/04—Priming; Preventing vapour lock using priming pumps; using booster pumps to prevent vapour-lock
    • 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
    • F04D15/02—Stopping of pumps, or operating valves, on occurrence of unwanted conditions
    • F04D15/0209—Stopping of pumps, or operating valves, on occurrence of unwanted conditions responsive to a condition of the working fluid
    • F04D15/0218—Stopping of pumps, or operating valves, on occurrence of unwanted conditions responsive to a condition of the working fluid the condition being a liquid level or a lack of liquid supply
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D5/00—Pumps with circumferential or transverse flow
    • F04D5/002—Regenerative pumps
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D5/00—Pumps with circumferential or transverse flow
    • F04D5/002—Regenerative pumps
    • F04D5/003—Regenerative pumps of multistage type
    • F04D5/006—Regenerative pumps of multistage type the stages being axially offset

Definitions

  • the invention relates to a centrifugal pump with a first normal-suction centrifugal pump stage arranged on the suction side, a pump suction nozzle lying axially at shaft height and at least one downstream self-priming centrifugal pump stage working with auxiliary liquid.
  • Pumps of this type are known (DEB-1528826), in particular for conveying media close to their boiling point, e.g. Liquefied gases, where any flow loss on the pump suction side must be avoided to prevent cavitation in the first pump stage.
  • the suction port lying axially at the level of the shaft is intended to avoid sharp diversions of the inflowing medium inside the pump before the first stage.
  • the suction line should also be routed to the container or tank to be pumped empty without major changes in direction, in order to keep the flow losses in the supply as low as possible.
  • a liquid storage space of sufficient size for the priming process is arranged between two pump stages, which is connected in its geodetically upper part to the preceding centrifugal pump stage and in its geodetically lower part to a subsequent centrifugal pump stage, a seal for sealing the shaft gap is arranged between the liquid storage space and the preceding centrifugal pump stage.
  • the liquid storage space between the normal priming first stage and the first following self-priming centrifugal pump stage, which means that the largest possible proportion of liquid when the pump drops, i.e. when the liquid flows back from the pressure line through the pump into the suction-side container, it is retained in the pump itself, since a, albeit small, portion of liquid also remains in the self-priming gyro stages following the storage space.
  • this liquid is then conveyed within a short time to the last self-priming stage, which is known to take over the priming alone and is then available to this stage as operating fluid for the priming process.
  • the liquid storage space arranged between two pump stages can now also be used according to the invention for the further purposes of liquid gas separation during the conveying process, in which case it is expediently arranged between the first and the second self-priming centrifugal stage and a connection for a in the region of the geodetically highest point of this liquid storage space Tapping line.
  • the Arranging the liquid storage space at this point has the advantage that a large part of the liquid portion that may be outgassed on the suction side of the pump and in the suction line is already condensed again due to compression by the fully loaded stage and the first self-priming stage and only a remainder at this point gasified medium is contained in the flow.
  • This residual portion of gaseous medium can then be returned to the suction-side tank or container via the extraction line provided in the highest point of the liquid storage space, so that only gas-free liquid is conveyed from the stages following the liquid storage space and leaves the pump pressure connection.
  • a correspondingly optimally dimensioned cross-section of the line leading back from the liquid storage space to the container or tank also allows a possible proportion of liquid flowing back with the gas to be reduced to a minimum, so that the pump efficiency is influenced only to an insignificant extent or not at all.
  • this space In order to increase the separation effect in the liquid storage space, it is proposed to design this space as a liquid gas separation and separation container by appropriate design and the installation of ribs. These internals also have the additional advantage that they also fall off when the pump drops, i.e. when the liquid flows back after switching off from the pressure line through the pump back into the suction-side container, brake the backflow of the medium and thereby retain a particularly large part of the liquid in the pump part which is connected downstream of the liquid storage space.
  • the axial extent of the liquid storage space should correspond approximately to the axial extent of a side channel step, since this retains sufficient liquid in the pump for the suction process.
  • the suction slot of the side channel pump stage following the liquid storage space be arranged in the geodetically lower area of the liquid storage space, so that the entire liquid supply of the storage space, even when the pump is restarted, serves the self-priming stages as an auxiliary or operating liquid for the suction process is available.
  • the liquid storage space is expediently connected to a device for automatically checking the liquid level in the liquid storage space, which emits a signal or prevents the pump from being started up if the liquid storage space does not contain a sufficient amount of liquid. Furthermore, it can be expedient if a time relay is provided, which switches the pump off again after switching on if the suction has not taken place within a certain predetermined time period. These measures result in securing the pump against running dry.
  • the pump shaft is designated 1 and once carries the fully loaded normal suction impeller 2 in the first pump stage, which is specially designed for optimal pumping speed, i.e. is designed for the lowest possible NPSH value of the pump, without placing particular value on the efficiency and delivery head of this first wheel.
  • the impellers of the following side channel stages are designated.
  • 4 is the pump suction housing with the suction port 5 and the inlet 6 arranged axially at shaft height.
  • the pump housing of the standard suction stage is designated 7, the housing parts of the following side channel pump stages are 8 and 9.
  • the pressure port 11 is located on the pump pressure housing 10 the pressure housing 10 still follows the mechanical seal or seal housing 12.
  • the liquid storage space 13 behind the first fully loaded centrifugal pump stage, the liquid storage space 13 is provided, the transition to the first fully loaded centrifugal pump stage is arranged in the geodetically upper region of the liquid storage space, above the partition wall 14, which separates the liquid storage space from the first fully loaded centrifugal pump stage. Furthermore, shaft seal 16 is provided between the housing part 15 forming the first storage space in the area of the shaft between this housing part and shaft 1, which prevents liquid in the area of the hub from passing from the liquid storage space or the downstream pump stages into the first pump stage.
  • the liquid storage space 13 is arranged behind the first self-priming and before the second self-priming side-channel centrifugal pump stage, the connection from the liquid storage space to the previous one Centrifugal pump stage takes place again in the geodetically upper area of the liquid storage space and above the partition 14, while a shaft seal 16 is again arranged between the shaft and the hub part of the housing 15.
  • 13 ribs 17 are provided in the liquid storage space, which are intended to bring about a separation between gas and liquid in the storage space, a removal opening 18 being additionally arranged at the geodetically highest point of the storage space; to return the gas components in the room 13 into the suction-side container or tank from which the pump sucks.
  • the self-priming pump stages are designed as side channel centrifugal pumps and the suction slot 19 of the side channel stage following the liquid storage space can be seen in the geodetically lowest point of the liquid storage space.
  • the pump shaft is supported in a slide bearing 20 and a ball bearing 21.
  • Fig. 3 can be seen on the base plate 22, the pump with the intake port 6, the housing part 7 of the first pump stage, the housing part 15 of the liquid reservoir and the housing parts 8 and 9 of the following self-priming stage.
  • the pump is driven by an electric motor 23.
  • a device 26 for determining the liquid level in the liquid storage space the electrical energy of which is supplied by a battery 27, is connected via connections 24, 25 to the upper or lower part of the housing part 15 of the liquid storage space.
  • Such devices for determining the liquid level are known and therefore do not require any explanation here.
  • the device is set in such a way that it emits a signal if, when the pump is switched on, the liquid level in the liquid storage room is below a certain limit which must be reached if the liquid in the liquid storage room is to be sufficient for the suction process.
  • the pump motor 23 is either prevented from running automatically and / or the operator is made aware of the insufficient fluid level in the pump so that it can provide a refill.
  • the device 26 is set up in such a way that when a certain time period has elapsed - for example 30 seconds - after the pump has started up, it is checked whether the pump has sucked in. If the suction has not taken place, the pump is switched off automatically.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)
  • Toys (AREA)

Abstract

The invention relates to a centrifugal pump having a first centrifugal pump stage (2), which is located on the suction side and is not self-priming, and having a pump inlet nozzle (6), which is located axially at the level of the horizontal shaft (1), and having at least one centrifugal pump stage (3). which is located downstream and which, operating with the aid of auxiliary liquid, is self-priming. According to the invention, the self-priming capability and reliability of the pump, in particular for conveying media in the vicinity of their boiling point, are improved by arranging a liquid reservoir (13), of sufficient size, between two pump stages, the connection from this reservoir to the preceding centrifugal pump stage being located in the geodetically upper portion of the reservoir, and a seal (16) for closing the shaft clearance being located between the liquid reservoir (13) and the preceding centrifugal pump stage.

Description

Die Erfindung bezieht sich auf eine Kreiselpumpe mit einer saugseitig angeordneten ersten normalsaugenden Kreiselpumpenstufe, einem axial auf Wellenhöhe liegenden Pumpenansaugstutzen und mindestens einer nachgeschalteten selbstansaugenden mit Hilfsflüssigkeit arbeitenden Kreiselpumpenstufe.The invention relates to a centrifugal pump with a first normal-suction centrifugal pump stage arranged on the suction side, a pump suction nozzle lying axially at shaft height and at least one downstream self-priming centrifugal pump stage working with auxiliary liquid.

Pumpen dieser Art sind bekannt (DEB-1528826), insbesondere zur Förderung von Medien nahe an ihrem Siedepunkt, so z.B. Flüssiggasen, wo jeder Strömungsverlust auf der Pumpensaugseite vermieden werden muss, um Kavitation in der ersten Pumpenstufe zu verhindern. Der axial auf Wellenhöhe liegende Saugstutzen soll scharfe Umleitungen des einströmenden Mediums innerhalb der Pumpe, vor der ersten Stufe, vermeiden. Von dem Saugstutzen ausgehend soll die Saugleitung ebenfalls ohne grosse Richtungsänderungen zu dem leer zu pumpenden Behälter oder Tank geführt werden, um auch hier in der Zuführung die Strömungsverluste möglichst gering zu halten.Pumps of this type are known (DEB-1528826), in particular for conveying media close to their boiling point, e.g. Liquefied gases, where any flow loss on the pump suction side must be avoided to prevent cavitation in the first pump stage. The suction port lying axially at the level of the shaft is intended to avoid sharp diversions of the inflowing medium inside the pump before the first stage. Starting from the suction nozzle, the suction line should also be routed to the container or tank to be pumped empty without major changes in direction, in order to keep the flow losses in the supply as low as possible.

Waren diese Pumpen bisher meist so aufgestellt, dass sie geodätisch unter dem zu entleerenden Behälter installiert waren, d.h. dass sie stets mit Zulauf arbeiten konnten, so brauchte auf die Selbstansaugefähigkeit und Abfallsicherheit dieser Pumpe kein besonderer Wert gelegt zu werden. Lediglich die unter ungünstigen Betriebsverhältnissen auf Pumpensaugseite ausgasenden Flüssigkeitsanteile mussten durch die selbstansaugende(n) Kreiselstufe bzw. -Stufen abgesaugt und mitgefördert werden können.Until now, these pumps were usually installed so that they were installed geodetically under the container to be emptied, i.e. that they could always work with an inlet, there was no need to put special emphasis on the self-priming and waste safety of this pump. Only the liquid components that gas out under unfavorable operating conditions on the pump suction side had to be sucked off and conveyed through the self-priming centrifugal stage or stages.

Infolge schärferer Sicherheitsbestimmungen geht man neuerdings jedoch häufig dazu über, die Behälter bzw. Tanks für z.B. Flüssiggase unterirdisch zu verlegen und steht so vor der Notwendigkeit, entweder eine entsprechend lange, sicher gekapselte, unzugängliche und konstruktiv aufwendige Tauchpumpe einzubauen, oder aber eine Pumpe im Saugbetrieb oberhalb des Behälters aufzustellen und diese dann entsprechend selbstansaugend und abfallsicher auszuführen. Die bisher bekannten Pumpen erfüllen diese letzten Forderungen nur sehr mangelhaft, da sie generell nach dem Stillstand und Abschalten bis zur Unterkante Saugstutzen leerlaufen und die dann in der Pumpe verbleibende Restflüssigkeit nicht mehr ausreicht, um bei Wiederinbetriebnahme eine sichere Entlüftung der Saugleitung und damit ein Wiederansaugen zu gewährleisten. Eine weitere Anforderung an die Förderung, insbesondere von Flüssiggasen, ist häufig die Abgabe blasen- bzw. gasfreien Mediums. Bei Pumpen, insbesondere wenn sie im Saugbereich unter schwierigen Saugbedingungen arbeiten müssen, lässt sich eine zumindest teilweise Verdampfung des Fördermediums im Saugbereich der Pumpe nicht verhindern, auch wenn diese Pumpen hinsichtlich des Saugvermögens optimal gestaltet sind. Durch den Druckanstieg in der Pumpe wird zwar ein Teil des in der Saugleitung bzw. im Ansaugbereich der Pumpe ausgegasten Mediums wieder verflüssigt, sicherheitshalber muss jedoch bei solchen Pumpen noch ein Gasabscheider nachgeschaltet werden, um auch sicherzustellen, dass garantiert blasen- und gasfreies Medium von der Pumpe geliefert wird.However, as a result of stricter safety regulations, there is now a frequent move towards using containers or tanks for e.g. Laying liquefied gases underground and therefore faces the need either to install a suitably long, securely encapsulated, inaccessible and structurally complex submersible pump, or to set up a pump in suction mode above the tank and then carry it out accordingly self-priming and waste-proof. The pumps known to date meet these last requirements only very poorly, since they generally run empty to the lower edge of the suction nozzle after standstill and shutdown and the residual liquid then remaining in the pump is no longer sufficient to ensure reliable ventilation of the suction line and thus re-suction when restarting guarantee. Another requirement for the promotion, especially of liquid gases, is often the delivery of bubble-free or gas-free medium. With pumps, especially if they have to work in the suction area under difficult suction conditions, an at least partial evaporation of the pumped medium in the suction area of the pump cannot be prevented, even if these pumps are optimally designed with regard to the pumping speed. Due to the pressure increase in the pump, part of the gas that is outgassed in the suction line or in the suction area of the pump is liquefied again, but for safety reasons, a gas separator must be installed downstream in such pumps to ensure that bubble-free and gas-free medium is guaranteed by the pump Pump is delivered.

Erfindungsgemäss wird der Mangel an ausreichender Selbstansaugefähigkeit und Abfallsicherheit dadurch beseitigt, dass zwischen zwei Pumpenstufen ein Flüssigkeitsvorratsraum mit für den Ansaugvorgang ausreichender Grösse angeordnet ist, der in seinem geodätisch oberen Teil mit der vorhergehenden Kreiselpumpenstufe und in seinem geodätisch unteren Teil mit einer folgenden Kreiselpumpenstufe verbunden ist, wobei zwischen dem Flüssigkeitsvorratsraum und der vorhergehenden Kreiselpumpenstufe eine Dichtung zur Abdichtung des Wellenspaltes angeordnet ist. Dadurch erreicht man, dass, wenn beim Stillsetzen der Pumpe Flüssigkeit aus der Druckleitung durch die Pumpe und die Saugleitung in den saugseitigen Tank oder Behälter zurückströmt, genügend Flüssigkeit in der Pumpe zurückbehalten wird, um ein Wiederansaugen beim Wiedereinschalten zu ermöglichen. In dem eingebauten Flüssigkeitsvorratsraum kann nämlich die Flüssigkeit nur aus dem geodätisch oberen Teil ablaufen bis zur Unterkante des Übertritts zur vorhergehenden Stufe. Auch ein Zurückströmen entlang des Wellenspaltes wird verhindert durch die vorgesehene Dichtung in diesem Bereich zwischen dem Flüssigkeitsvorratsraum und der vorhergehenden Pumpenstufe.According to the invention, the lack of sufficient self-priming capability and waste safety is eliminated in that a liquid storage space of sufficient size for the priming process is arranged between two pump stages, which is connected in its geodetically upper part to the preceding centrifugal pump stage and in its geodetically lower part to a subsequent centrifugal pump stage, a seal for sealing the shaft gap is arranged between the liquid storage space and the preceding centrifugal pump stage. This ensures that if liquid stops flowing from the pressure line through the pump and the suction line back into the suction tank or container when the pump is stopped, sufficient liquid is retained in the pump to enable it to be sucked in again when it is switched on again. In the built-in liquid storage space, the liquid can only drain from the geodetically upper part to the lower edge of the transition to the previous step. Backflow along the shaft gap is also prevented by the seal provided in this area between the liquid storage space and the preceding pump stage.

In weiterer Ausführung des Erfindungsgedankens wird vorgeschlagen, den Flüssigkeitsvorratsraum zwischen der normalsaugenden ersten Stufe und der ersten folgenden selbstansaugenden Kreiselpumpenstufe anzuordnen, wodurch man erreicht, dass ein möglichst grosser Flüssigkeitsanteil beim Abfallen der Pumpe, d.h. beim Zurückströmen der Flüssigkeit aus der Druckleitung durch die Pumpe in den saugseitigen Behälter, in der Pumpe selbst zurückgehalten wird, da in den dem Vorratsraum nachfolgenden selbstansaugenden Kreiselstufen ebenfalls ein, wenn auch nur geringer, Anteil Flüssigkeit zurückbleibt. Diese Flüssigkeit wird beim Wiederanstellen der Pumpe dann binnen kurzer Zeit in die letzte selbstansaugende Stufe gefördert, die bekanntlich allein das Ansaugen übernimmt und steht dieser Stufe dann als Betriebsflüssigkeit für den Ansaugvorgang zur Verfügung.In a further embodiment of the inventive concept, it is proposed to arrange the liquid storage space between the normal priming first stage and the first following self-priming centrifugal pump stage, which means that the largest possible proportion of liquid when the pump drops, i.e. when the liquid flows back from the pressure line through the pump into the suction-side container, it is retained in the pump itself, since a, albeit small, portion of liquid also remains in the self-priming gyro stages following the storage space. When the pump is switched on again, this liquid is then conveyed within a short time to the last self-priming stage, which is known to take over the priming alone and is then available to this stage as operating fluid for the priming process.

Der zwischen zwei Pumpenstufen angeordnete Flüssigkeitsvorratsraum lässt sich erfindungsgemäss nun auch noch zu den weiteren Zwecken der Flüssigkeitsgastrennung während des Fördervorgangs benutzen, wobei man ihn dann zweckmässigerweise zwischen der ersten und der zweiten selbstansaugenden Kreiselstufe anordnet und im Bereich des geodätisch höchsten Punktes dieses Flüssigkeitsvorratsraumes einen Anschluss für eine Entnahmeleitung vorsieht. Die Anordnung des Flüssigkeitsvorratsraumes an dieser Stelle hat den Vorteil, dass ein grosser Teil des auf der Saugseite der Pumpe und in der Saugleitung möglicherweise ausgegasten Flüssigkeitsanteiles infolge Verdichtung durch die vollbeaufschlagte Stufe und die erste selbstansaugende Stufe bereits wieder kondensiert ist und an dieser Stelle nur noch ein Rest vergastes Medium in dem Förderstrom enthalten ist. Dieser Restanteil von gasförmigem Medium kann dann über die im höchsten Punkt des Flüssigkeitsvorratsraumes vorgesehene Entnahmeleitung in den saugseitigen Tank oder Behälter zurückgeführt werden, so dass von den dem Flüssigkeitsvorratsraum folgenden Stufen, nur noch gasfreie Flüssigkeit gefördert wird und den Pumpendruckstutzen verlässt. Durch entsprechend optimal bemessenen Querschnitt der vom Flüssigkeitsvorratsraum zum Behälter bzw. Tank zurückführenden Leitung lässt sich auch ein möglicherweise mit dem Gas zurückströmender Flüssigkeitsanteil auf ein Minimum reduzieren, so dass der Pumpenwirkungsgrad dadurch nur unwesentlich oder überhaupt nicht spürbar beinflusst wird.The liquid storage space arranged between two pump stages can now also be used according to the invention for the further purposes of liquid gas separation during the conveying process, in which case it is expediently arranged between the first and the second self-priming centrifugal stage and a connection for a in the region of the geodetically highest point of this liquid storage space Tapping line. The Arranging the liquid storage space at this point has the advantage that a large part of the liquid portion that may be outgassed on the suction side of the pump and in the suction line is already condensed again due to compression by the fully loaded stage and the first self-priming stage and only a remainder at this point gasified medium is contained in the flow. This residual portion of gaseous medium can then be returned to the suction-side tank or container via the extraction line provided in the highest point of the liquid storage space, so that only gas-free liquid is conveyed from the stages following the liquid storage space and leaves the pump pressure connection. A correspondingly optimally dimensioned cross-section of the line leading back from the liquid storage space to the container or tank also allows a possible proportion of liquid flowing back with the gas to be reduced to a minimum, so that the pump efficiency is influenced only to an insignificant extent or not at all.

Um den Abscheideeffekt in dem Flüssigkeitsvorratsraum zu erhöhen, wird vorgeschlagen, diesen Raum durch entsprechende Gestaltung und den Einbau von Rippen speziell als Flüssigkeitsgas-Abscheide- und -Trennbehälter auszubilden. Diese Einbauten haben darüber hinaus zusätzlich den Vorteil, dass sie auch beim Abfallen der Pumpe, d.h. beim Zurückströmen der Flüssigkeit nach dem Abschalten aus der Druckleitung durch die Pumpe in den saugseitigen Behälter zurück, den Rückfluss des Mediums bremsen und dadurch ein besonders grosser Teil von Flüssigkeit in dem Pumpenteil, der dem Flüssigkeitsvorratsraum nachgeschaltet ist, zurückhalten.In order to increase the separation effect in the liquid storage space, it is proposed to design this space as a liquid gas separation and separation container by appropriate design and the installation of ribs. These internals also have the additional advantage that they also fall off when the pump drops, i.e. when the liquid flows back after switching off from the pressure line through the pump back into the suction-side container, brake the backflow of the medium and thereby retain a particularly large part of the liquid in the pump part which is connected downstream of the liquid storage space.

Besonders geeignet für die Verwendung in einer solchen Pumpe, haben sich selbstansaugende Kreiselpumpenstufen in Form von Seitenkanaistufen erwiesen, da sie eine optimale Selbstansaugefähigkeit besitzen. Die axiale Erstreckung des Flüssigkeitsvorratsraumes sollte in diesem Fall etwa der axialen Erstreckung einer Seitenkanalstufe entsprechen, da dadurch ausreichend Flüssigkeit zum Wiederansaugvorgang in der Pumpe zurückgehalten wird.Self-priming centrifugal pump stages in the form of side channel stages have proven particularly suitable for use in such a pump, since they have optimal self-priming capability. In this case, the axial extent of the liquid storage space should correspond approximately to the axial extent of a side channel step, since this retains sufficient liquid in the pump for the suction process.

Um die optimale Ansaugfähigkeit zu gewährleisten wird schliesslich vorgeschlagen, dass der Saugschlitz der dem Flüssigkeitsvorratsraum folgenden Seitenkanalpumpenstufe im geodätisch unteren Bereich des Flüssigkeitsvorratsraumes angeordnet ist, damit der gesamte Flüssigkeitsvorrat des Vorratsraumes auch bei Wiederinbetriebnahme der Pumpe den selbstansaugenden Stufen als Hilfs- bzw. Betriebsflüssigkeit für den Ansaugvorgang zur Verfügung steht.Finally, in order to ensure the optimal suction capacity, it is proposed that the suction slot of the side channel pump stage following the liquid storage space be arranged in the geodetically lower area of the liquid storage space, so that the entire liquid supply of the storage space, even when the pump is restarted, serves the self-priming stages as an auxiliary or operating liquid for the suction process is available.

Zweckmässigerweise ist der Flüssigkeitsvorratsraum mit einer Einrichtung zur selbsttätigen Kontrolle des Flüssigkeitsstandes im Flüssigkeitsvorratsraum verbunden, die ein Signal abgibt oder die Inbetriebnahme der Pumpe verhindert, wenn der Flüssigkeitsvorratsraum keine ausreichende Flüssigkeitsmenge enthält. Ferner kann es zweckmässig sein, wenn ein Zeitrelais vorgesehen ist, das die Pumpe nach dem Einschalten dann wieder abschaltet, wenn innerhalb einer bestimmten vorgegebenen Zeitspanne das Ansaugen nicht stattgefunden hat. Diese Massnahmen ergeben eine Sicherung der Pumpe gegen Trokkenlauf.The liquid storage space is expediently connected to a device for automatically checking the liquid level in the liquid storage space, which emits a signal or prevents the pump from being started up if the liquid storage space does not contain a sufficient amount of liquid. Furthermore, it can be expedient if a time relay is provided, which switches the pump off again after switching on if the suction has not taken place within a certain predetermined time period. These measures result in securing the pump against running dry.

Anhand der beigefügten Zeichnungen sei die Erfindung beispielsweise erläutert.

  • Fig. 1 zeigt den Längsschnitt durch eine 5-stufige Kreiselpumpe, wobei der Flüssigkeitsvorratsraum hinter der ersten normalsaugenden Kreiselpumpenstufe angeordnet ist.
  • Fig. zeigt ebenfalls den Längsschnitt durch eine 5-stufige Kreiselpumpe, bei der jedoch der Flüssigkeitsvorratsraum hinter der ersten selbstansaugenden Kreiselpumpenstufe angeordnet ist.
  • Fig.3 zeigt eine perspektivische Darstellung der Pumpenanordnung.
The invention will be explained, for example, with reference to the accompanying drawings.
  • 1 shows the longitudinal section through a 5-stage centrifugal pump, the liquid storage space being arranged behind the first normal-suction centrifugal pump stage.
  • Fig. Also shows the longitudinal section through a 5-stage centrifugal pump, in which, however, the liquid storage space is arranged behind the first self-priming centrifugal pump stage.
  • 3 shows a perspective view of the pump arrangement.

In den Figuren ist die Pumpenwelle mit 1 bezeichnet und trägt einmal das voll beaufschlagte normalsaugende Kreiselrad 2 in der ersten Pumpenstufe, das speziell für ein optimales Saugvermögen, d.h. für einen möglichst niedrigen NPSH-Wert der Pumpe ausgelegt ist, ohne auf Wirkungsgrad und Förderhöhe bei diesem ersten Rad besonderen Wert zu legen. Mit 3 sind die Flügelräder der folgenden Seitenkanalstufen bezeichnet. 4 ist das Pumpensauggehäuse mit dem Saugstutzen 5 und dem axial auf Wellenhöhe angeordneten Einlauf 6. Das Pumpengehäuse der normalsaugenden ersten Stufe ist mit 7 bezeichnet, die Gehäuseteile der folgenden Seitenkanalpumpenstufen mit 8 bzw. 9. Am Pumpendruckgehäuse 10 befindet sich der Druckstutzen 11. Anschliessend an das Druckgehäuse 10 folgt noch das Gleitringdichtungs- oder Dichtungsgehäuse 12.In the figures, the pump shaft is designated 1 and once carries the fully loaded normal suction impeller 2 in the first pump stage, which is specially designed for optimal pumping speed, i.e. is designed for the lowest possible NPSH value of the pump, without placing particular value on the efficiency and delivery head of this first wheel. With 3 the impellers of the following side channel stages are designated. 4 is the pump suction housing with the suction port 5 and the inlet 6 arranged axially at shaft height. The pump housing of the standard suction stage is designated 7, the housing parts of the following side channel pump stages are 8 and 9. The pressure port 11 is located on the pump pressure housing 10 the pressure housing 10 still follows the mechanical seal or seal housing 12.

In Fig. 1 ist nun hinter der ersten vollbeaufschlagten Kreiselpumpenstufe der Flüssigkeitsvorratsraum 13 vorgesehen, dessen Übertritt zur ersten vollbeaufschlagten Kreiselpumpenstufe im geodätisch oberen Bereich des Flüssigkeitsvorratsraumes angeordnet ist, oberhalb der Trennwand 14, die den Flüssigkeitsvorratsraum von der ersten vollbeaufschlagten Kreiselpumpenstufe trennt. Weiter sind zwischen dem den ersten Vorratsraum bildenden Gehäusetei) 15 im Bereich der Welle zwischen diesem Gehäuseteil und Welle 1 Wellendichtung 16 vorgesehen, die ein Übertreten von Flüssigkeit im Bereich der Nabe aus dem Flüssigkeitsvorratsraum oder den nachgeschalteten Pumpenstufen in die erste Pumpenstufe verhindern.In Fig. 1, behind the first fully loaded centrifugal pump stage, the liquid storage space 13 is provided, the transition to the first fully loaded centrifugal pump stage is arranged in the geodetically upper region of the liquid storage space, above the partition wall 14, which separates the liquid storage space from the first fully loaded centrifugal pump stage. Furthermore, shaft seal 16 is provided between the housing part 15 forming the first storage space in the area of the shaft between this housing part and shaft 1, which prevents liquid in the area of the hub from passing from the liquid storage space or the downstream pump stages into the first pump stage.

In Fig. 2 ist der Flüssigkeitsvorratsraum 13 hinter der ersten selbstansaugenden und vor der zweiten selbstansaugenden Seitenkanalkreiselpumpenstufe angeordnet, die Verbindung vom Flüssigkeitsvorratsraum zur vorhergehenden Kreiselpumpenstufe erfolgt wieder im geodätisch oberen Bereich des Flüssigkeitsvorratsraumes und zwar oberhalb der Trennwand 14, während zwischen Welle und Nabenteil des Gehäuses 15 wiederum eine Wellendichtung 16 angeordnet ist. Darüber hinaus sind im Flüssigkeitsvorratsraum 13 Rippen 17 vorgesehen, die eine Trennung zwischen Gas und Flüssigkeit im Vorratsraum bewirken sollen, wobei zusätzlich am geodätisch höchsten Punkt des Vorratsraumes noch eine Entnahmeöffnung 18 angeordnet ist; zur Rückführung der im Raum 13 befindlichen Gasanteile in den saugseitigen Behälter oder Tank aus dem die Pumpe ansaugt. Die selbstansaugenden Pumpenstufen sind in beiden Beispielen als Seitenkanalkreiselpumpen ausgeführt und der Saugschlitz 19 der dem Flüssigkeitsvorratsraum folgenden Seitenkanalstufe ist im geodätisch tiefsten Punkt des Flüssigkeitsvorratsraumes zu erkennen.In FIG. 2, the liquid storage space 13 is arranged behind the first self-priming and before the second self-priming side-channel centrifugal pump stage, the connection from the liquid storage space to the previous one Centrifugal pump stage takes place again in the geodetically upper area of the liquid storage space and above the partition 14, while a shaft seal 16 is again arranged between the shaft and the hub part of the housing 15. In addition, 13 ribs 17 are provided in the liquid storage space, which are intended to bring about a separation between gas and liquid in the storage space, a removal opening 18 being additionally arranged at the geodetically highest point of the storage space; to return the gas components in the room 13 into the suction-side container or tank from which the pump sucks. In both examples, the self-priming pump stages are designed as side channel centrifugal pumps and the suction slot 19 of the side channel stage following the liquid storage space can be seen in the geodetically lowest point of the liquid storage space.

Zu erwähnen ist noch, dass die Pumpenwelle in einem Gleitlager 20 und einem Kugellager 21 gelagert wird.It should also be mentioned that the pump shaft is supported in a slide bearing 20 and a ball bearing 21.

In Fig. 3 erkennt man auf der Grundplatte 22 die Pumpe mit dem Ansaugstutzen 6, dem Gehäuseteil 7 der ersten Pumpenstufe, dem Gehäuseteil 15 des Flüssigkeitsvorratsraums und den Gehäuseteilen 8 und 9 der folgenden selbstansaugenden Stufe. Die Pumpe wird angetrieben von einem Elektromotor 23. An den oberen bzw unteren Teil des Gehäuseteils 15 des Flüssigkeitsvorratsraumes ist über Anschlüsse 24, 25 ein Gerät 26 zur Bestimmung des Flüssigkeitsstandes im Flüssigkeitsvorratsraum angeschlossen, dessen elektrische Energie von einer Batterie 27 geliefert wird. Derartige Geräte zur Feststellung des Flüssigkeitsstandes sind bekannt und bedürfen daher hier keiner Erläuterung. Das Gerät ist so eingestellt, dass es ein Signal abgibt, wenn beim Einschalten der Pumpe der Flüssigkeitsstand im Flüssigkeitsvorratsraum unterhalb einer bestimmten Grenze liegt, die erreicht werden muss, wenn die im Flüssigkeitsvorratsraum enthaltene Flüssigkeit für den Ansaugvorgang ausreichen soll. Wenn diese Signal erscheint, wird entweder das Laufen des Pumpenmotors 23 selbsttätig verhindert und/oder es wird die Bedienungsperson auf den unzureichenden Flüssigkeitsstand in der Pumpe aufmerksam gemacht, damit sie für eine Auffüllung sorgen kann.In Fig. 3 can be seen on the base plate 22, the pump with the intake port 6, the housing part 7 of the first pump stage, the housing part 15 of the liquid reservoir and the housing parts 8 and 9 of the following self-priming stage. The pump is driven by an electric motor 23. A device 26 for determining the liquid level in the liquid storage space, the electrical energy of which is supplied by a battery 27, is connected via connections 24, 25 to the upper or lower part of the housing part 15 of the liquid storage space. Such devices for determining the liquid level are known and therefore do not require any explanation here. The device is set in such a way that it emits a signal if, when the pump is switched on, the liquid level in the liquid storage room is below a certain limit which must be reached if the liquid in the liquid storage room is to be sufficient for the suction process. When this signal appears, the pump motor 23 is either prevented from running automatically and / or the operator is made aware of the insufficient fluid level in the pump so that it can provide a refill.

Ausserdem ist das Gerät 26 so eingerichtet, dass selbsttätig bei Ablauf einer bestimmten Zeitperiode - beispielsweise 30 Sekunden - nach dem Anlaufen der Pumpe überprüft wird, ob die Pumpe angesaugt hat. Wenn das Ansaugen nicht stattgefunden hat, wird die Pumpe selbsttätig abgeschaltet.In addition, the device 26 is set up in such a way that when a certain time period has elapsed - for example 30 seconds - after the pump has started up, it is checked whether the pump has sucked in. If the suction has not taken place, the pump is switched off automatically.

Entsprechendes gilt, wenn die Pumpe während des Betriebs abfällt, d.h. keine Flüssigkeit angesaugt wird.The same applies if the pump drops during operation, i.e. no liquid is sucked in.

Claims (8)

1. Centrifugal pump with a first normally intaking centrifugal pump stage (2) aranged on the intake side, with a pump intake conncector (5) lying axially at the level of the horizontal shaft (1) and with a least one downstream self-priming centrifugal pump stage (3) operating with auxiliary fluid, characterised in that between two pump stages there is disposed a fluid supply chamber (13) of sufficient size for the priming process, which chamber is connected in its geodetically upper part with the preceding centrifugal pump stage (2) and in its geodetically lower part with a following centrifugal pump stage (3), a seal (16) being arranged between the fluid supply chamber (13) and the preceding centrifugal pump stage (2) for sealing the shaft clearance.
2. Centrifugal pump according to Claim 1, characterised in that the fluid supply chamber (13) is disposed between the normally intaking first stage (2) and the following first self-priming centrifugal pump stage (3).
3. Centrifugal pump according to Claim 1, characterised in that the fluid supply chamber (13) is disposed between the first and the second self-priming stage (3) and that a connection (18) for a bleed pipe is arranged in the vicinity of the geodetically highest point of the fluid supply chamber.
4. Centrifugal pump according to Claims 1 to 3, characterised in that by corresponding shaping and by installing ribs (17) the fluid supply chamber (13) ist designed as a liquid/gas separating or dividing container.
5. Centrifugal pump according to Claims 1 to 4, characterised in that the self-priming centrifugal pump stage (3) are designed as side channel stages and the axial extent of the fluid supply chamber (13) corresponds approximately to the axial extent of one side channel stage.
6. Centrifugal pump according to Claims 5, characterised in that the intake slot (19) of the side channel pump stage (3) following the fluid supply chamber (13) is arranged in the geodetically lower zone of the fluid supply chamber.
7. Centrifugal pump according to one of the Claims 1 to 6, characterised in that the fluid supply chamber (13) is connected to means (26) for sensing the fluid level in the fluid supply chamber, which means is arranged to emit a signal when the fluid level in the fluid supply chamber falls below a predetermined level.
8. Centrifugal pump according to one of the Claims 1 to 7, characterised in that the pump is connected with means (26) for sensing the fluid filling into the fluid supply chamber (13), which means is arranged to emit a signal when the pump has not primed within a predetermined time interval.
EP81105972A 1980-08-05 1981-07-29 Self-priming rotary pump, particularly for bringing liquids to their boiling point Expired EP0045483B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT81105972T ATE5433T1 (en) 1980-08-05 1981-07-29 SELF-PRIMING CENTRIFUGAL PUMP, PARTICULARLY FOR PUMPING LIQUIDS NEAR THEIR BOILING POINT.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3029604 1980-08-05
DE3029604 1980-08-05

Publications (3)

Publication Number Publication Date
EP0045483A2 EP0045483A2 (en) 1982-02-10
EP0045483A3 EP0045483A3 (en) 1982-02-17
EP0045483B1 true EP0045483B1 (en) 1983-11-23

Family

ID=6108913

Family Applications (1)

Application Number Title Priority Date Filing Date
EP81105972A Expired EP0045483B1 (en) 1980-08-05 1981-07-29 Self-priming rotary pump, particularly for bringing liquids to their boiling point

Country Status (9)

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US (1) US4390317A (en)
EP (1) EP0045483B1 (en)
AT (1) ATE5433T1 (en)
AU (1) AU542218B2 (en)
CA (1) CA1165624A (en)
DK (1) DK149932C (en)
ES (1) ES504574A0 (en)
HK (1) HK39685A (en)
NZ (1) NZ197872A (en)

Families Citing this family (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2553835B1 (en) * 1983-10-25 1986-02-28 Bertin & Cie FLUID COMPRESSION MACHINE WITH MULTIPLE SERIES COMPRESSION STAGES
DE3425656C2 (en) * 1984-07-12 1994-12-08 Sero Pumpenfabrik Gmbh Centrifugal pump
DE3539251A1 (en) * 1985-11-06 1987-05-14 Klein Schanzlin & Becker Ag MULTI-STAGE CENTRIFUGAL PUMP FOR CONVEYING LIQUID GAS
DE3717058A1 (en) * 1987-05-21 1988-12-08 Bayer Ag MIXER FOR MIXING AT LEAST TWO FLOWABLE SUBSTANCES, ESPECIALLY UNDERSTANDING OR. INITIATING A REACTION DURING MIXING
DE4113029A1 (en) * 1991-04-20 1992-10-22 Sihi Gmbh & Co Kg SELF-PRIMING CENTRIFUGAL PUMP FOR CONVEYING LIQUIDS NEAR YOUR BOILING POINT
DE4241406C2 (en) * 1992-12-09 2001-10-18 Bosch Gmbh Robert Blower housing
JPH0886298A (en) * 1994-09-19 1996-04-02 Hitachi Ltd Dry turbo vacuum pump
DE29513904U1 (en) * 1995-08-30 1997-01-09 Sihi Gmbh & Co Kg Side channel centrifugal pump with stage packages in sheet metal construction
IT1398142B1 (en) * 2010-02-17 2013-02-14 Nuovo Pignone Spa SINGLE SYSTEM WITH COMPRESSOR AND INTEGRATED PUMP AND METHOD.
EP2893194B1 (en) * 2012-09-03 2016-11-30 Sterling Industry Consult GmbH Side channel pump and method for operating same
US11560902B2 (en) 2019-01-25 2023-01-24 Pentair Flow Technologies, Llc Self-priming assembly for use in a multi-stage pump

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE711791C (en) * 1938-04-28 1941-10-07 Anna Dickow Geb Driemeyer Arrangement of the drive for a non-self-priming centrifugal pump
US2553066A (en) * 1944-06-30 1951-05-15 Southern John Self-priming centrifugal pump
DE1528826A1 (en) * 1951-01-28 1969-11-20 Siemen & Hinsch Gmbh Centrifugal pump
DE888207C (en) * 1951-08-10 1953-08-31 Siemens Ag Self-priming pump
US3385225A (en) * 1965-06-29 1968-05-28 Siemen & Hinsch Gmbh Rotary pump
DE2534740C3 (en) * 1975-08-04 1983-02-03 Franz 4630 Bochum Klaus Canned centrifugal pump

Also Published As

Publication number Publication date
EP0045483A3 (en) 1982-02-17
NZ197872A (en) 1985-03-20
AU7369181A (en) 1982-02-11
DK149932C (en) 1987-10-12
DK346881A (en) 1982-02-06
EP0045483A2 (en) 1982-02-10
ES8206774A1 (en) 1982-08-16
ES504574A0 (en) 1982-08-16
CA1165624A (en) 1984-04-17
HK39685A (en) 1985-05-31
DK149932B (en) 1986-10-27
AU542218B2 (en) 1985-02-14
ATE5433T1 (en) 1983-12-15
US4390317A (en) 1983-06-28

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