EP0902192B1 - Volute casing pump - Google Patents

Volute casing pump Download PDF

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Publication number
EP0902192B1
EP0902192B1 EP98115674A EP98115674A EP0902192B1 EP 0902192 B1 EP0902192 B1 EP 0902192B1 EP 98115674 A EP98115674 A EP 98115674A EP 98115674 A EP98115674 A EP 98115674A EP 0902192 B1 EP0902192 B1 EP 0902192B1
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EP
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Prior art keywords
rib
housing
centrifugal pump
casing
rib parts
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EP98115674A
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German (de)
French (fr)
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EP0902192A3 (en
EP0902192A2 (en
Inventor
Stephan Dr. Bross
Peter Hergt
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KSB AG
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KSB AG
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00—Details, component parts, or accessories
    • F04D29/40—Casings; Connections of working fluid
    • F04D29/42—Casings; Connections of working fluid for radial or helico-centrifugal pumps
    • F04D29/44—Fluid-guiding means, e.g. diffusers
    • F04D29/445—Fluid-guiding means, e.g. diffusers especially adapted for liquid 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
    • F04D29/00—Details, component parts, or accessories
    • F04D29/40—Casings; Connections of working fluid
    • F04D29/42—Casings; Connections of working fluid for radial or helico-centrifugal pumps
    • F04D29/44—Fluid-guiding means, e.g. diffusers
    • F04D29/445—Fluid-guiding means, e.g. diffusers especially adapted for liquid pumps
    • F04D29/448—Fluid-guiding means, e.g. diffusers especially adapted for liquid pumps bladed diffusers

Definitions

  • the invention relates to a centrifugal pump with a housing of the type Double spiral and with a rib arranged therein as a partition, the rib is formed at least in two parts, with between the rib parts one or more stomata are formed, and a housing spur opposite rib part is for this purpose with a gap opening Distance arranged.
  • a double spiral housing consists of two staggered by 180 ° Spiral halves in which a fluid flowing out of the impeller is collected and is supplied to a common pressure port. Because of the quasi mirror-image arrangement of the two spiral halves arises along one Impeller circumference an approximately symmetrical pressure distribution, the resulting force components cancel each other out.
  • a double spiral casing is created in that a simple spiral housing So-called rib is used as a partition, which is in the direction of rotation of the impeller seen about 180 ° after a spur forms a second spiral half. The Side of the rib facing away from the impeller, the back, limits one Bypass channel through which a fluid collected in the first spiral half in the pressure port is directed.
  • CH-A 219 739 is a rotary conveyor with a spiral housing known, in which the problem was to be solved by inside the housing cross currents to avoid the resulting losses.
  • several partition walls are used in the spiral housing, so Form constant pressure channels.
  • the dimensions of such as constant pressure channels trained guide channels are such that the cross section only in the ratio the loss of speed is changed by the friction. With such Equal pressure channels can, however, have the radial force effect of a double spiral housing not be improved.
  • the invention is therefore based on the problem of developing a double spiral housing which has a good spiral force profile with simple, in particular casting technology, production.
  • the solution to this problem provides that the wrap angle ⁇ of a rib part depending on the number n of rib parts used in the range of 0.7 ⁇ 360 ° 2 * n ⁇ 1.1 ⁇ 360 ° 2 * n lies.
  • the rib parts used can therefore be of the same length or of different lengths.
  • This solution allows for spiral casings, the rib of which is at least in two parts is formed, wherein one or more stomata between the rib parts are trained, a problem-free manufacture of a double spiral housing, the cross section of which can be of any design.
  • the well-known Rectangular, trapezoidal, pear spirals etc. can be used without any problems.
  • the rib By forming the rib as a multi-part component, which is made of at least two spaced apart, one gap opening forming rib parts is a simple placement of the rib parts possible within the spiral and there remains a balanced pressure distribution preserved along the circumference of the impeller. Furthermore, this results in opposite a simple spiral housing an improved radial force curve.
  • Accessibility is improved if the one facing the housing spur Rib part with a gap forming a gap opening is arranged. This measure improves in the area of the double spiral rib parts forming the accessibility to the flow channels created therefrom.
  • One embodiment of the invention provides that the angular position ⁇ of the first rib part, viewed in the direction of flow, relative to the housing spur in the range of 0.8 360 ° n ⁇ 360 ° n ⁇ 1.2 lies. It is then sufficient that the distance and the position of the rib parts from one another is set such that access to the flow channels delimited by the rib parts is ensured by the gap openings existing between the rib parts and between the rib part and the housing current. For this purpose, the distance between the leading edges of the rib parts is set so that sufficiently large stomata are formed in the area of the rib parts.
  • the angular difference of the rib parts ⁇ corresponds to the condition 0.8 ⁇ ⁇ 1.5 ⁇ ⁇
  • the profiles of the rib parts can have the same or different shapes, the rib length having no influence due to the reference to the blade leading edges. It has proven to be advantageous for a further reduction in the radial forces if the leading edges of the rib parts are arranged on circles with diameters D r , the ratios of which to the impeller diameter D 2 are in the range from 1.03 ⁇ D r D 2 ⁇ 1.15 lies.
  • the diameters on which the leading edges of the individual rib parts are arranged do not have to be identical, but the leading edges of the rib parts can be located on different diameters.
  • the radial forces are also reduced in that the leading edge is one of the Rib parts are always arranged on a smaller diameter than one end a rib part in front of it in the direction of flow.
  • the spiral casing is of course designed so that the limited by a rib part Bypass channel does not hinder the outflow of the fluid from the first spiral part or adversely affected.
  • the profile of the rib parts is not subject to any restrictions. It can Rib parts with a constant thickness or a predetermined thickness distribution Find use. It is also possible that the rib parts are different Can have profile shapes. Such a formation of a rib is one Very easy casting production of a double spiral housing possible. It also offers the advantage that such rib parts in a simple manner can be retrofitted. One sees an additional possibility adjustable arrangement of the rib parts in front. Depending on the arrangement of the axis of rotation on the double rib part, these can be used in their angle of attack compared to that from the Impeller emerging flow can be changed.
  • the reduction in radial force has a positive effect the invention also the measure, according to which in the from the housing spur outgoing first quadrant of the double spiral housing compared to one normal spiral development there is an increase in cross-sectional area.
  • the housing 1 shows a housing 1 of a centrifugal pump, in which the outer diameter D 2 is represented by an impeller.
  • the housing 1 is designed here in the manner of a double spiral housing, the first spiral part 3, seen in the direction of flow, starting at the housing spur 4.
  • the housing spur 4 is in the first quadrant, in which a pressure port 5 is also located.
  • the first spiral part 3 has an increasing cross-sectional enlargement, which in this example reaches its maximum at the end of the II. Quadrant. From here, a fluid is led through a bypass channel 6, 7 to the pressure port 5.
  • the bypass duct 6, 7 is delimited by the wall surface of the housing 1 and the wall surface of the rib parts 8, 9 used here. Similar to a double spiral housing, these rib parts 8, 9 form the other or second spiral part.
  • a gap opening 10 located between the rib parts 8, 9 and a gap opening 11 located between the housing spur 4 and the end of the rib part 9 enable access to the bypass channels 6, 7 during the manufacture of the housing can be easily removed and the cast surface plastered.
  • the flow-bearing surfaces can thus be given a roughness, with the aid of which the efficiency of such a pump housing can be improved.
  • the rib parts 8, 9 shown here can have a constant thickness d or, as shown, can be provided with a blade profile the same or different.
  • the rib part 8 is shown longer than the rib part 9.
  • the position of the first rib part 8 seen in the flow direction in relation to the housing spur 4 lying in the first housing quadrant is determined by the angle ⁇ .
  • This angular position ⁇ results according to formula (2).
  • the distance ⁇ shown in FIG. 1 between the leading edges 12, 13 of the rib parts 8, 9 is defined by the formula (3) listed above.
  • the leading edges 12, 13 of the rib parts 8, 9 lie on circles with a diameter D r , the ratio of which to the impeller diameter D 2 according to Formula 4 is in the range of 1.03 ⁇ D r D 2 ⁇ 1.15 lies.
  • Quadrant of the housing 1 arranged rib part 8 is shorter here, while the rib part 9 located in the fourth quadrant has a greater overall length.
  • a measure, which is shown here in the first quadrant of the housing 1, also has a positive effect on a reduction in the radial force.
  • An enlargement of the spiral cross section in this area, which increases compared to normal spiral development, is shown here by a broken line.
  • the housing spur 4 is also at a greater distance from the outer diameter D 2 of an impeller.
  • the cross-sectional area enlargement 14 in the first quadrant of the spiral housing and the position of the rib parts 8, 9 in relation to one another and on the housing spur 4 are adapted to the hydraulics of an impeller used in each case and the respective spiral shape. This allows radial force reductions to be achieved which correspond to the radial force curve of a traditional double spiral design. With the aid of variations in relation to the position of the leading edges 12, 13, the shape and the size of the rib parts 8, 9, it is possible to influence the course of the radial force.

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

Abstract

A housing for a centrifugal pump has a double spiral shape formed by two or more equal length ribs (8,9) around the impeller. The ribs are separated by gaps (10,11) between the ribs and between the last rib and the edge (4) of the outlet duct. The leading edge (12,13) of a rib is at a smaller radius than the trailing edge of the preceding rib. The angle subtended by a rib is between 0.7 and 1.1 times 360 degrees divided by twice the rib count.

Description

Die Erfindung betrifft eine Kreiselpumpe mit einem Gehäuse nach Art einer Doppelspirale und mit darin angeordneten, als Trennwand ausgebildeten Rippe, die Rippe ist mindestens zweiteilig ausgebildet, wobei zwischen den Rippenteilen ein oder mehrere Spaltöffnungen ausgebildet sind, und ein einem Gehäusesporn gegenüberliegender Rippenteil ist dazu mit einem eine Spaltöffnung bildenden Abstand angeordnet.The invention relates to a centrifugal pump with a housing of the type Double spiral and with a rib arranged therein as a partition, the rib is formed at least in two parts, with between the rib parts one or more stomata are formed, and a housing spur opposite rib part is for this purpose with a gap opening Distance arranged.

Bei Kreiselpumpen ist eine durch Wechselwirkung von Laufrad und Pumpengehäuse bzw. Leitrad erzeugte hydraulische Radialkraft bekannt, die in der Ebene des Laufrades liegt. Solche Radialkräfte sind diversen Einflüssen unterworfen, wie sie beispielsweise im KSB-Kreiselpumpenlexikon, 3. Auflage, 1989, Seiten 242 und 243 beschrieben sind. Einfache Spiralgehäusepumpen besitzen im Auslegepunkt entlang des Laufradumfanges eine nahezu konstante Druck- oder Geschwindigkeitsverteilung. In diesem Punkt kann eine Spiralgehäusepumpe nahezu radialkraftfrei betrieben werden. Wird jedoch eine einfache Spiralgehäusepumpe aufgrund geänderter Betriebsbedingungen im Teillast- oder Überlastbereich gefahren, dann führt dies zu ansteigenden Radialkräften infolge sich ändernder Druck- bzw. Geschwindigkeitsverteilungen entlang des Laufradumfanges.In centrifugal pumps, this is due to the interaction of the impeller and Pump housing or stator generated hydraulic radial force known in the level of the impeller. Such radial forces are diverse influences subject, as for example in the KSB centrifugal pump lexicon, 3rd edition, 1989, pages 242 and 243. Simple volute casing pumps have an almost constant at the design point along the wheel circumference Pressure or speed distribution. At this point one Spiral casing pump can be operated almost without radial force. However, will simple volute casing pump due to changed operating conditions in the Partial or overload range, then this leads to increasing Radial forces due to changing pressure or speed distributions along the wheel circumference.

Dieser Nachteil führte zur Entwicklung von Doppelspiralgehäusen, wie sie beispielsweise durch die US-A-2 955 540 bekannt sind, und bei denen die Radialkräfte über den gesamten Betriebsbereich auf einem niedrigen Niveau liegen. Ein Doppelspiralgehäuse besteht aus zwei um 180° versetzte Spiralhälften, in denen ein aus dem Laufrad ausströmendes Fluid gesammelt und einem gemeinsamen Druckstutzen zugeführt wird. Aufgrund der quasi spiegelbildlichen Anordnung der zwei Spiralhälften entsteht entlang eines Laufradumfanges eine annähernd symmetrische Druckverteilung, deren resultierende Kraftkomponenten sich gegenseitig aufheben. Ein Doppelspiralgehäuse wird dadurch geschaffen, daß in einem einfachen Spiralgehäuse eine sogenannte Rippe als Trennwand eingesetzt ist, die in Laufraddrehrichtung gesehen ca. 180° nach einem Gehäusesporn eine zweite Spiralhälfte bildet. Die vom Laufrad abgekehrte Seite der Rippe, die Rückseite, begrenzt einen Umführungskanal, durch den ein in der ersten Spiralhälfte gesammeltes Fluid in den Druckstutzen geleitet wird.This disadvantage led to the development of double spiral casings like the one shown for example, are known from US-A-2 955 540, and in which the Radial forces over the entire operating range at a low level lie. A double spiral housing consists of two staggered by 180 ° Spiral halves in which a fluid flowing out of the impeller is collected and is supplied to a common pressure port. Because of the quasi mirror-image arrangement of the two spiral halves arises along one Impeller circumference an approximately symmetrical pressure distribution, the resulting force components cancel each other out. A double spiral casing is created in that a simple spiral housing So-called rib is used as a partition, which is in the direction of rotation of the impeller seen about 180 ° after a spur forms a second spiral half. The Side of the rib facing away from the impeller, the back, limits one Bypass channel through which a fluid collected in the first spiral half in the pressure port is directed.

Die fertigungstechnische Herstellung von Doppelspiralgehäusen ist aufwendig und kostenintensiv, da die für einen Abguß notwendigen langen Gehäusekerne aufwendig gesichert werden müssen, um während des Gußvorganges nicht aufzuschwimmen. Nach der Fertigstellung des Gußes bereitet die Entfernung der Kerne erhebliche Schwierigkeiten beim Gußputzen. Aus diesem Grunde werden häufig zusätzliche Löcher in der Pumpengehäusewand vorgesehen, die nach der Entfernung der Gußkerne in aufwendiger Weise drucksicher verschweißt werden müssen. Trotz dieser Maßnahmen kann in den schwer zugänglichen Bereichen des Doppelspiralgehäuses nur eine unvollständige Oberflächenbearbeitung erfolgen, wodurch Wirkungsgradeinbußen die Folge sind. Zur Vermeidung dieser Nachteile ist es durch die US-A-2 955 540 bekannt, die Rippe als separates Einzelteil auszubilden und nachträglich in ein gegossenes Spiralgehäuse einzusetzen. Diese Maßnahme erleichtert zwar die Oberflächenbearbeitung des Gußteiles beim Putzen, sie erfordert jedoch einen hohen mechanischen Aufwand bei der Herstellung eines Doppelspiralgehäuses, wodurch sich kein Kostenvorteil ergibt.The manufacturing of double spiral housings is complex and expensive costly, since the long housing cores necessary for a casting need to be laboriously secured so as not during the casting process float. After the casting is completed, the removal of the Cores considerable difficulties when cleaning the cast. For this reason often additional holes are provided in the pump housing wall, which after the Removal of the cast cores can be welded in a pressure-proof manner in a complex manner have to. Despite these measures, areas that are difficult to access of the double spiral housing only an incomplete surface treatment occur, resulting in a loss of efficiency. To avoid this Disadvantages are known from US-A-2 955 540, the rib as a separate one Form individual part and subsequently in a cast spiral housing use. This measure makes the surface processing of the Cast part when cleaning, but it requires a high mechanical effort in the manufacture of a double spiral casing, which results in no cost advantage results.

Aus diesem Grunde erfolgten Forschungstätigkeiten, die sich mit der Geometrie der Rippen von Doppelspiralgehäusen auseinandersetzen und deren Radialkraftverlauf untersuchten. So ist es beispielsweise durch die US-A-3 289 598 bekannt, daß durch Variation der Länge der Rippe bzw. der Variation des Umschlingungswinkels dieser Rippe eine Änderung im Radialkraftverlauf eintreten kann. In Fig. 7 der US-A-3 289 598 sind die Radialkraftverläufe von veränderten Rippen gezeigt. Eine Verkürzung bringt nur eine unwesentliche fertigungstechnische Verbesserung und hat den zusätzlichen Nachteil, daß die Verkürzung mit einem Ansteigen der Radialkräfte im Teillast- und Überlastbereich verbunden ist. For this reason, research has been done dealing with geometry the ribs of double spiral casings and their Examined radial force curve. For example, US-A-3,289 598 known that by varying the length of the rib or the variation of the A change in the radial force curve occurs at the wrap angle of this rib can. In Fig. 7 of US-A-3,289,598 the radial force profiles are changed Ribs shown. A shortening brings only an insignificant manufacturing improvement and has the additional disadvantage that the Shortened with an increase in radial forces in the partial load and overload range connected is.

Durch die CH-A 219 739 ist eine Kreiselfördermaschine mit Spiralgehäuse bekannt, bei der das Problem zu lösen war, durch innerhalb des Gehäuses entstehende Querströmungen die dadurch bedingten Verluste zu vermeiden. Dazu werden in dem Spiralgehäuse mehrere Trennungswände eingesetzt, um so Gleichdruckkanäle auszubilden. Die Abmessungen solcher als Gleichdruckkanäle ausgebildeten Führungskanäle sind derart, daß der Querschnitt nur im Verhältnis des Geschwindigkeitsverlustes durch die Reibung verändert wird. Mit solchen Gleichdruckkanälen kann jedoch die Radialkraftauswirkung eines Doppelspiralgehäuses nicht verbessert werden.CH-A 219 739 is a rotary conveyor with a spiral housing known, in which the problem was to be solved by inside the housing cross currents to avoid the resulting losses. For this purpose, several partition walls are used in the spiral housing, so Form constant pressure channels. The dimensions of such as constant pressure channels trained guide channels are such that the cross section only in the ratio the loss of speed is changed by the friction. With such Equal pressure channels can, however, have the radial force effect of a double spiral housing not be improved.

Der Erfindung liegt daher das Problem zugrunde, ein Doppelspiralgehäuse zu entwickeln, das bei einfacher, insbesondere gußtechnischer, Herstellung einen guten Spiralkraftverlauf aufweist. Die Lösung dieses Problems sieht vor, daß der Umschlingungswinkel ϕ eines Rippenteiles in Abhängigkeit von der Anzahl n der verwendeten Rippenteile im Bereich von 0.7·360°2·n ≤ϕ≤1.1·360°2·n liegt. Die Verwendung findenden Rippenteile können also gleich lang oder unterschiedlich lang ausgebildet sein.The invention is therefore based on the problem of developing a double spiral housing which has a good spiral force profile with simple, in particular casting technology, production. The solution to this problem provides that the wrap angle ϕ of a rib part depending on the number n of rib parts used in the range of 0.7 · 360 ° 2 * n ≤φ≤1.1 · 360 ° 2 * n lies. The rib parts used can therefore be of the same length or of different lengths.

Diese Lösung ermöglicht bei Spiralgehäusen, deren Rippe mindestens zweiteilig ausgebildet ist, wobei zwischen den Rippenteilen ein oder mehrere Spaltöffnungen ausgebildet sind, eine problemlose Herstellung eines Doppelspiralgehäuses, dessen Querschnitt beliebig ausgebildet sein kann. Die bekannten Rechteck-, Trapez-, Birnenspiralen usw. können problemlos Anwendung finden. Durch die Ausbildung der Rippe als ein mehrteiliges Bauteil, welches aus mindestens zwei mit Abstand zueinander angeordneten, eine Spaltöffnung bildenden Rippenteilen besteht, ist eine einfache Plazierung der Rippenteile innerhalb der Spirale möglich und es bleibt eine ausgeglichene Druckverteilung entlang des Laufradumfanges erhalten. Weiterhin ergibt sich dadurch gegenüber einem einfachen Spiralgehäuse ein verbesserter Radialkraftverlauf. Dadurch kann die Radialkraft im gesamten Lastbereich der Pumpe reduziert werden. Durch die mit Abstand zueinander erfolgende Anordnung der Rippenteile ist zwischen diesen eine Spaltöffnung ausgebildet, die aufwendige zusätzliche Stützen für einen Gußkern entbehrlich macht. Diese hat den Vorteil, daß damit die Strömungswege im Bereich der Rippenteile beim Gußputzen wesentlich leichter zugänglich sind.This solution allows for spiral casings, the rib of which is at least in two parts is formed, wherein one or more stomata between the rib parts are trained, a problem-free manufacture of a double spiral housing, the cross section of which can be of any design. The well-known Rectangular, trapezoidal, pear spirals etc. can be used without any problems. By forming the rib as a multi-part component, which is made of at least two spaced apart, one gap opening forming rib parts is a simple placement of the rib parts possible within the spiral and there remains a balanced pressure distribution preserved along the circumference of the impeller. Furthermore, this results in opposite a simple spiral housing an improved radial force curve. This can the radial force in the entire load range of the pump can be reduced. Through the spaced arrangement of the rib parts is between this a gap opening formed, the expensive additional supports for makes a casting core unnecessary. This has the advantage that the Flow paths in the area of the rib parts when cleaning castings are much easier are accessible.

Die Zugänglichkeit wird verbessert, wenn der einem Gehäusesporn gegenüberliegende Rippenteil dazu mit einem eine Spaltöffnung bildenden Abstand angeordnet ist. Diese Maßnahme verbessert im Bereich der die Doppelspirale bildenden Rippenteile die Zugänglichkeit zu den davon geschaffenen Strömungskanälen.Accessibility is improved if the one facing the housing spur Rib part with a gap forming a gap opening is arranged. This measure improves in the area of the double spiral rib parts forming the accessibility to the flow channels created therefrom.

Eine Ausgestaltung der Erfindung sieht vor, daß die Winkellage τ des in Strömungsrichtung gesehen ersten Rippenteil bezogen auf den Gehäusesporn im Bereich von 0.8 ·360°n ≤τ≤360°n ·1.2 liegt. Es genügt dann, daß der Abstand und die Lage der Rippenteile zueinander so eingestellt wird, daß durch die zwischen den Rippenteilen sowie zwischen Rippenteil und Gehäusespom bestehenden Spaltöffnungen ein Zugang zu den von den Rippenteilen begrenzten Strömungskanälen sichergestellt wird. Dazu wird der Abstand zwischen den Anströmkanten der Rippenteile so eingestellt, daß im Bereich der Rippenteile genügend große Spaltöffnungen entstehen. Die Winkeldifferenz der Rippenteile Δτ entspricht der Bedingung 0.8·ϕ≤Δτ≤1.5·ϕ One embodiment of the invention provides that the angular position τ of the first rib part, viewed in the direction of flow, relative to the housing spur in the range of 0.8 360 ° n ≤τ≤ 360 ° n · 1.2 lies. It is then sufficient that the distance and the position of the rib parts from one another is set such that access to the flow channels delimited by the rib parts is ensured by the gap openings existing between the rib parts and between the rib part and the housing current. For this purpose, the distance between the leading edges of the rib parts is set so that sufficiently large stomata are formed in the area of the rib parts. The angular difference of the rib parts Δτ corresponds to the condition 0.8 · φ≤Δτ≤1.5 · φ

Die Profile der Rippenteile können gleiche oder ungleiche Formen aufweisen, wobei durch den Bezug auf die Schaufelanströmkanten die Rippenlänge ohne Einfluß bleibt. Es hat sich als vorteilhaft für eine weitere Absenkung der Radialkräfte herausgestellt, wenn die Anströmkanten der Rippenteile auf Kreisen mit Durchmessern Dr angeordnet sind, deren Verhältnisse zum Laufraddurchmesser D2 im Bereich von 1.03≤ Dr D 2 ≤1.15 liegt. Die Durchmesser, auf denen die Anströmkanten der einzelnen Rippenteile angeordnet sind, müssen nicht identisch sein, sondern die Anströmkanten der Rippenteile können auf verschiedenen Durchmessern befindlich sein.The profiles of the rib parts can have the same or different shapes, the rib length having no influence due to the reference to the blade leading edges. It has proven to be advantageous for a further reduction in the radial forces if the leading edges of the rib parts are arranged on circles with diameters D r , the ratios of which to the impeller diameter D 2 are in the range from 1.03≤ D r D 2 ≤1.15 lies. The diameters on which the leading edges of the individual rib parts are arranged do not have to be identical, but the leading edges of the rib parts can be located on different diameters.

Die Radialkräfte werden auch dadurch reduziert, daß die Anströmkante eines der Rippenteile immer auf einem kleineren Durchmesser angeordnet ist, als ein Ende eines in Strömungsrichtung davor befindlichen Rippenteiles. Das Spiralgehäuse ist selbstverständlich so ausgebildet, daß der von einem Rippenteil begrenzte Umführungskanal den Abfluß des Fluid aus dem ersten Spiralteil nicht behindert oder nachteilig beeinflußt.The radial forces are also reduced in that the leading edge is one of the Rib parts are always arranged on a smaller diameter than one end a rib part in front of it in the direction of flow. The spiral casing is of course designed so that the limited by a rib part Bypass channel does not hinder the outflow of the fluid from the first spiral part or adversely affected.

Das Profil der Rippenteile unterliegt keinen Beschränkungen. Es können Rippenteile mit konstanter Dicke oder auch einer vorgegebenen Dickenverteilung Verwendung finden. Ebenso ist es möglich, daß die Rippenteile unterschiedliche Profilformen aufweisen können. Durch eine solche Ausbildung einer Rippe ist eine sehr leichte gußtechnische Herstellung eines Doppelspiralgehäuses möglich. Es bietet gleichzeitig den Vorteil, daß solche Rippenteile in einfacher Weise auch nachträglich montiert werden können. Eine zusätzliche Möglichkeit sieht eine verstellbare Anordnung der Rippenteile vor. Je nach Anordnung der Drehachse am Doppelrippenteil, können diese in ihrem Anstellwinkel gegenüber der aus dem Laufrad austretenden Strömung verändert werden.The profile of the rib parts is not subject to any restrictions. It can Rib parts with a constant thickness or a predetermined thickness distribution Find use. It is also possible that the rib parts are different Can have profile shapes. Such a formation of a rib is one Very easy casting production of a double spiral housing possible. It also offers the advantage that such rib parts in a simple manner can be retrofitted. One sees an additional possibility adjustable arrangement of the rib parts in front. Depending on the arrangement of the axis of rotation on the double rib part, these can be used in their angle of attack compared to that from the Impeller emerging flow can be changed.

Positiv auf die Radialkraftabsenkung wirkt sich nach einer weiteren Ausgestaltung der Erfindung auch die Maßnahme aus, wonach in dem vom Gehäusesporn ausgehenden ersten Quadranten des Doppelspiralgehäuses gegenüber einer normalen Spiralentwicklung eine Querschnittsflächenvergrößerung erfolgt.According to a further embodiment, the reduction in radial force has a positive effect the invention also the measure, according to which in the from the housing spur outgoing first quadrant of the double spiral housing compared to one normal spiral development there is an increase in cross-sectional area.

Es hat sich gezeigt, daß mit solchen Maßnahmen ein Radialkraftverlauf erreichbar ist, der annähernd dem Radialkraftverlauf eines konventionellen Doppelspiralgehäuses entspricht. Die geringfügigen Unterschiede sind aber vernachlässigbar, da die durch die einfachere Fertigung erzielbaren Vorteile dieses bei weitem aufwiegen. It has been shown that a radial force profile can be achieved with such measures is approximately the radial force curve of a conventional one Double spiral housing corresponds. The slight differences are, however negligible because of the advantages that can be achieved by simpler production by far outweigh this.

Ausführungsbeispiele der Erfindung sind in den Zeichnungen dargestellt und werden im folgenden näher beschrieben. Es zeigen die

  • Fig. 1 und 2 verschiedene Ausführungsformen der mehrteiligen Doppelspiralrippe.
    • Embodiments of the invention are shown in the drawings and are described in more detail below. They show
  • 1 and 2 different embodiments of the multi-part double spiral rib.

    • In der Fig. 1 ist ein Gehäuse 1 einer Kreiselpumpe gezeigt, in dem von einem Laufrad der Außendurchmesser D2 dargestellt ist. Das Gehäuse 1 ist hier nach Art eines Doppelspiralgehäuses ausgebildet, wobei der in Strömungsrichtung gesehen erste Spiralteil 3 am Gehäusesporn 4 beginnt. Der Gehäusesporn 4 liegt hierbei im I. Quadranten, in dem auch ein Druckstutzen 5 befindlich ist. Der erste Spiralteil 3 weist eine zunehmende Querschnittsvergrößerung auf, die in diesem Beispiel am Ende des II. Quadranten ihr Maximum erreicht. Von hier aus wird ein Fluid durch einen Umführungskanal 6, 7 zum Druckstutzen 5 geführt. Der Umführungskanal 6, 7 wird begrenzt von der Wandfläche des Gehäuses 1 sowie der Wandfläche der hier Verwendung findenden Rippenteile 8, 9. Diese Rippenteile 8, 9 bilden, ähnlich wie bei einem Doppelspiralgehäuse, den anderen oder zweiten Spiralteil. Eine zwischen den Rippenteilen 8, 9 befindliche Spaltöffnung 10 sowie eine zwischen dem Gehäusesporn 4 und dem Ende des Rippenteiles 9 befindliche Spaltöffnung 11 ermöglichen bei der Gehäuseherstellung einen Zugang zu den Umführungskanälen 6, 7. Somit kann beispielsweise bei einem gegossenen Gehäuse ein dort Verwendung findender Gehäusekern leicht entfernt werden und die Gußoberfläche verputzt werden. Damit können die strömungsführenden Oberflächen eine Rauhigkeit erhalten, mit deren Hilfe der Wirkungsgrad eines solchen Pumpengehäuses verbessert werden kann.1 shows a housing 1 of a centrifugal pump, in which the outer diameter D 2 is represented by an impeller. The housing 1 is designed here in the manner of a double spiral housing, the first spiral part 3, seen in the direction of flow, starting at the housing spur 4. The housing spur 4 is in the first quadrant, in which a pressure port 5 is also located. The first spiral part 3 has an increasing cross-sectional enlargement, which in this example reaches its maximum at the end of the II. Quadrant. From here, a fluid is led through a bypass channel 6, 7 to the pressure port 5. The bypass duct 6, 7 is delimited by the wall surface of the housing 1 and the wall surface of the rib parts 8, 9 used here. Similar to a double spiral housing, these rib parts 8, 9 form the other or second spiral part. A gap opening 10 located between the rib parts 8, 9 and a gap opening 11 located between the housing spur 4 and the end of the rib part 9 enable access to the bypass channels 6, 7 during the manufacture of the housing can be easily removed and the cast surface plastered. The flow-bearing surfaces can thus be given a roughness, with the aid of which the efficiency of such a pump housing can be improved.

    Die hier dargestellten Rippenteile 8, 9 können eine konstante Dicke d aufweisen oder, wie gezeigt, mit einem Schaufelprofil versehen gleich oder unterschiedlich sein. Das Rippenteil 8 ist bei diesem Ausführungsbeispiel länger dargestellt als das Rippenteil 9. Die Lage des in Strömungsrichtung gesehen ersten Rippenteiles 8 in Bezug auf den im I. Gehäusequadranten liegenden Gehäusesporn 4 wird durch den Winkel τ bestimmt. Diese Winkellage τ ergibt sich gemäß Formel (2). Mit Hilfe der oben aufgeführten Formel (1) kann in Abhängigkeit von der Anwendung findenden Anzahl (n) der verwendeten Rippenteile 8, 9 deren Umschlingungswinkel ϕ bestimmt werden. Der in Fig. 1 dargestellte Abstand Δτ zwischen den Anströmkanten 12, 13 der Rippenteile 8, 9 wird durch die oben aufgeführte Formel (3) definiert. Die Anströmkanten 12, 13 der Rippenteile 8, 9 liegen auf Kreisen mit einem Durchmesser Dr, deren Verhältnisse zum Laufraddurchmesser D2 gemäß Formel 4 im Bereich von 1.03 ≤ Dr D 2 ≤1.15 liegt. The rib parts 8, 9 shown here can have a constant thickness d or, as shown, can be provided with a blade profile the same or different. In this exemplary embodiment, the rib part 8 is shown longer than the rib part 9. The position of the first rib part 8 seen in the flow direction in relation to the housing spur 4 lying in the first housing quadrant is determined by the angle τ. This angular position τ results according to formula (2). With the help of the formula (1) listed above, depending on the number (n) of the rib parts 8, 9 used, their wrap angle ϕ can be determined. The distance Δτ shown in FIG. 1 between the leading edges 12, 13 of the rib parts 8, 9 is defined by the formula (3) listed above. The leading edges 12, 13 of the rib parts 8, 9 lie on circles with a diameter D r , the ratio of which to the impeller diameter D 2 according to Formula 4 is in the range of 1.03 ≤ D r D 2 ≤1.15 lies.

    Die Fig. 2 zeigt gegenüber der Fig. 1 eine andere Art der Anordnung der Rippenteile 8, 9. Das im III. Quadranten des Gehäuse 1 angeordnete Rippenteil 8 ist hier kürzer ausgebildet, während das im IV. Quadranten befindliche Rippenteil 9 eine größere Baulänge aufweist. Positiv auf eine Radialkraftabsenkung wirkt sich auch eine Maßnahme aus, die hier im I. Quadranten des Gehäuses 1 dargestellt ist. Eine in diesem Bereich erfolgende Vergrößerung des Spiralquerschnitts, der gegenüber einer normalen Spiralentwicklung zunimmt, ist hier durch eine gestrichelte Darstellung gezeigt. Auch der Gehäusesporn 4 weist einen größeren Abstand gegenüber dem Außendurchmesser D2 eines Laufrades auf. Die Querschnitts-flächenvergrößerung 14 im I. Quadranten des Spiralgehäuses sowie die Lage der Rippenteile 8, 9 im Bezug zueinander und auf den Gehäusesporn 4 wird an die jeweils Anwendung findende Hydraulik eines Laufrades und der jeweilige Spiralform angepaßt. Damit sind Radialkraftabsenkungen erreichbar, die dem Radialkraftverlauf einer traditionellen Doppelspiralausbildung entsprechen. Auch mit Hilfe von Variationen in Bezug auf die Lage der Anströmkanten 12, 13, der die Form und die Größe der Rippenteile 8, 9 ist eine Einflußnahme auf den Verlauf der Radialkraft möglich.2 shows a different type of arrangement of the rib parts 8, 9 compared to FIG. 1. Quadrant of the housing 1 arranged rib part 8 is shorter here, while the rib part 9 located in the fourth quadrant has a greater overall length. A measure, which is shown here in the first quadrant of the housing 1, also has a positive effect on a reduction in the radial force. An enlargement of the spiral cross section in this area, which increases compared to normal spiral development, is shown here by a broken line. The housing spur 4 is also at a greater distance from the outer diameter D 2 of an impeller. The cross-sectional area enlargement 14 in the first quadrant of the spiral housing and the position of the rib parts 8, 9 in relation to one another and on the housing spur 4 are adapted to the hydraulics of an impeller used in each case and the respective spiral shape. This allows radial force reductions to be achieved which correspond to the radial force curve of a traditional double spiral design. With the aid of variations in relation to the position of the leading edges 12, 13, the shape and the size of the rib parts 8, 9, it is possible to influence the course of the radial force.

    Claims (6)

    1. Centrifugal pump with a casing of the double volute type and with a rib arranged therein in the form of a dividing wall, the rib being of an at least two-part form, one or more gap openings (10) being formed between the rib parts (8, 9) and a rib part (9) lying opposite a casing spur (4) being arranged at a distance with respect to it, forming a gap opening (11), characterized in that, depending on the number n of rib parts (8, 9) used, the angle of wrap (4) of a rib part (8, 9) lies in the range 0.7·360°2·n ≤ϕ≤1.1·360°2·n
    2. Centrifugal pump according to Claim 1, characterized in that the angular position (τ) of the first rib part (8), seen in the direction of flow, in relation to the casing spur (4) lies in the range 0.8360°n ≤τ≤360°n ·1.2
    3. Centrifugal pump according to Claim 1 or 2, characterized in that an angular difference Δτ between the leading edges (12, 13) of the rib parts (8, 9), defining the size of the gap openings (10, 11), satisfies the condition 0.8·ϕ≤Δτ≤1.5·ϕ
    4. Centrifugal pump according to one of Claims 1, 2 or 3, characterized in that the leading edges (12, 13) of the rib parts (8, 9) are arranged on circles of the same or different diameters (Dr) known per se, the relationship of the diameters Dr to the impeller diameter D2 lying in the range 1.03≤ Dr D 2 ≤1.15
    5. Centrifugal pump according to one of Claims 1 to 4, characterized in that the rib parts (8, 9) are arranged adjustably in the double volute casing.
    6. Centrifugal pump according to one of Claims 1 to 5, characterized in that a cross-sectional area enlargement (14), in comparison with a normal volute development, takes place in the 1st quadrant of the double volute casing, proceeding from the casing spur (4).
    EP98115674A 1997-09-15 1998-08-20 Volute casing pump Expired - Lifetime EP0902192B1 (en)

    Applications Claiming Priority (2)

    Application Number Priority Date Filing Date Title
    DE19740590A DE19740590A1 (en) 1997-09-15 1997-09-15 Volute casing pump
    DE19740590 1997-09-15

    Publications (3)

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    EP0902192A2 EP0902192A2 (en) 1999-03-17
    EP0902192A3 EP0902192A3 (en) 1999-07-14
    EP0902192B1 true EP0902192B1 (en) 2003-06-11

    Family

    ID=7842447

    Family Applications (1)

    Application Number Title Priority Date Filing Date
    EP98115674A Expired - Lifetime EP0902192B1 (en) 1997-09-15 1998-08-20 Volute casing pump

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    US (1) US6146095A (en)
    EP (1) EP0902192B1 (en)
    AT (1) ATE242845T1 (en)
    BR (1) BR9803538A (en)
    DE (2) DE19740590A1 (en)

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    GB0415301D0 (en) * 2004-07-08 2004-08-11 Weir Pumps Ltd Pump casing
    DE202005004180U1 (en) * 2005-03-14 2006-07-27 Ebm-Papst Landshut Gmbh centrifugal blower
    MX2010009173A (en) * 2008-02-22 2010-11-12 Horton Inc Hybrid flow fan apparatus.
    CA2703855C (en) * 2009-07-31 2018-12-11 Rem Enterprises Inc. Improved air vacuum pump for a particulate loader and transfer apparatus
    CN102080671B (en) * 2009-11-27 2015-05-13 德昌电机(深圳)有限公司 Centrifugal pump
    BR112012028455A8 (en) 2010-05-07 2017-03-01 Sulzer Pumpen Ag VOLUTE-SHAPED PUMP ENCLOSURE WITH DIVIDING RIB
    MX2014012948A (en) 2012-04-27 2015-02-10 Weir Minerals Australia Ltd Centrifugal pump casing with offset discharge.
    EP2954214B1 (en) * 2013-02-08 2021-03-03 Sulzer Management AG Fluid flow engine and flow guide element for a fluid flow engine
    US20170067481A1 (en) * 2015-09-03 2017-03-09 Fluid Handling Llc Volute Design For Lower Manufacturing Cost and Radial Load Reduction
    CN105243222B (en) * 2015-10-27 2018-08-31 湖南湘电长沙水泵有限公司 Design method for changing cast guide vane into welded guide vane, welded guide vane and guide vane body
    CN108843619B (en) * 2018-06-28 2020-05-22 西安交通大学 Double-volute structure of centrifugal pump
    CN112483417B (en) * 2020-12-14 2022-12-27 万载志成实业有限公司 Circulating pump for selenium silver gold production process
    US11873837B1 (en) * 2021-08-02 2024-01-16 W.S. Darley & Co. Centrifugal pumps, casings and vehicles using the same

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    Also Published As

    Publication number Publication date
    EP0902192A3 (en) 1999-07-14
    DE19740590A1 (en) 1999-03-18
    ATE242845T1 (en) 2003-06-15
    DE59808677D1 (en) 2003-07-17
    EP0902192A2 (en) 1999-03-17
    BR9803538A (en) 1999-11-23
    US6146095A (en) 2000-11-14

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