EP0153221B1 - Production method for a closed impeller - Google Patents

Production method for a closed impeller Download PDF

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Publication number
EP0153221B1
EP0153221B1 EP85400203A EP85400203A EP0153221B1 EP 0153221 B1 EP0153221 B1 EP 0153221B1 EP 85400203 A EP85400203 A EP 85400203A EP 85400203 A EP85400203 A EP 85400203A EP 0153221 B1 EP0153221 B1 EP 0153221B1
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EP
European Patent Office
Prior art keywords
disc
blades
discs
wheel
flange
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Expired
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EP85400203A
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German (de)
French (fr)
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EP0153221A1 (en
Inventor
Georges Dousse
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Areva NP SAS
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Framatome SA
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Publication date
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Priority to AT85400203T priority Critical patent/ATE37589T1/en
Publication of EP0153221A1 publication Critical patent/EP0153221A1/en
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Publication of EP0153221B1 publication Critical patent/EP0153221B1/en
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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
    • F04D29/18—Rotors
    • F04D29/22—Rotors specially for centrifugal pumps
    • F04D29/2205—Conventional flow pattern
    • F04D29/2222—Construction and assembly

Definitions

  • the present invention relates to the production of a closed centrifugal or centripetal impeller. It applies in particular to the wheels of pumps or other centrifugal or centripetal machines in which the radial flow path of the fluid is closed.
  • the invention relates to an impeller in accordance with the preamble of claim 1.
  • Centrifugal compressors consist of a shaft carrying one or more wheels intended to compress the gas which passes through the compressor.
  • the wheels have a hub disc for mounting on the shaft and vanes attached to the disc which create a flow channel for the gas.
  • the gas sucked in at the level of the shaft, rises along the disc, driven in rotation by the blades, up to the outside diameter of the disc, having received kinetic energy from the wheel.
  • the transformation at the exit of the wheel from kinetic energy into pressure energy corresponds to compression.
  • the usual method of manufacturing these wheels can consist of milling the blades in the hub, and attaching the flange by welding to the side face of the blades.
  • the blades can also be machined in the flange, the latter then being attached by welding to the hub. They can also be made in two parts, one of the parts being machined in the hub and the other in the flange, the flange and the hub then being made integral with one another by welding. In all these embodiments, it is the weld which is used to secure the various elements of the wheel.
  • document US-A-1 919970 describes the production of a closed paddle wheel in which a disc, provided with blades, forming a hub, is assembled with two discs provided with blades and forming flanges, by means of a series of screws.
  • the invention overcomes the drawbacks of the above-mentioned methods of making wheels. It aims at a simple, rapid process, making it possible to obtain very good quality wheels capable of withstanding even difficult operating conditions.
  • the invention also relates to a wheel obtained by means of this method.
  • only one of the two discs is provided with vanes by providing studs on them and provision is made for housings corresponding to these studs in the thickness of the other disc.
  • punctual housings are provided and an angular setting is carried out before shrinking in order to allow the pins to be compared with the corresponding housings.
  • vanes are provided on each of the two discs, by providing pins on the vanes located on one of the discs and corresponding housings on the vanes located on the other disc and l 'an angular setting is carried out before shrinking in order to allow each blade to be compared with a corresponding blade of the other disc.
  • only one of the two discs is provided with vanes and these vanes are produced with a flange at their end situated at the periphery of the disc, and the second disc is produced. with a diameter such that the second disc can be kept clamped between said flanges.
  • said flanges are interconnected so as to form a rim in which the second disc can be held tight.
  • one of the two discs is provided with vanes and the second disc is produced with peripheral flanges extended by a rim such that the first disc and the vanes can be held tight respectively between the rim and the edges and an angular setting is carried out before shrinking in order to allow each blade to be compared with a corresponding edge of the second disc.
  • the invention also relates to a closed paddle wheel produced by means of any one of the abovementioned variants of the method according to the invention.
  • the wheel consists of two discs, a disc 1 forming a hub and a second disc 2 also called a flange.
  • the two discs 1 and 2 are each provided with a central bore, the and 2 ', to allow the mounting of the wheel on a shaft not shown of the machine on which the wheel is intended to be used.
  • Blades 3 are intended to create a flow channel for the gas which, drawn in at the level of the shaft, that is to say bores, rises along the disks 1 and 2, driven in rotation by the blades 3, to the outside diameter of the discs 1 and 2 having received kinetic energy from the wheel.
  • the discs 1 and 2 produce with the blades 3 channels which are each isolated from the neighboring channels.
  • two discs are first prepared, a hub 1 and a flange 2, as shown in Figures 1b, 2b, 3b and 4b. These discs are prepared by providing them with blades 3.
  • the hub 1 which carries the blades 3.
  • the hub 1 and the blades 3 have been machined from the same block of metal; we could also weld the blades 3 on the hub 1, but as we explained above, welding has certain drawbacks that we are specifically trying to avoid.
  • the hub 1 bearing blades 3 and the flange 2 are produced in such a way that they can be made integral with one another in order to constitute a closed wheel, by hooping.
  • each of the two discs 1 and 2 is provided with means capable of cooperating with corresponding means of the other disc.
  • the blades 3 carried by the hub 1 are provided with pins 4 corresponding to housings 5 machined in the thickness of the flange 2.
  • the machining of the pins 4 and of the housings 5 can be practiced circumferentially, by turning, which ensures good precision and allows a low production cost to be obtained.
  • the housings 5 can also be punctual, that is to say produced by braking only at the level of the vanes 3: this ensures continuity of the flange 2 and of the flow of gas thereon.
  • the flange 2 is previously heated to a temperature allowing its expansion but not modifying its structure, then the flange 2 is placed on the hub 1 by fitting the pins 4 into the housings 5.
  • the hub 1 and the flange 2 are made integral with one another.
  • the housings 5 and the pins 4 are provided so as to be able to fit together when the flange 2 is heated and to be under stress when the flange 2 is cooled; this constraint must be able to be supported by the metals constituting the hub 1 and the flange 2 both at rest and in operation.
  • housings 5 are punctual, it is necessary to provide an angular setting when positioning the flange 2 on the disc 1, so that the housings 5 can fit into the studs 4 located on the blades 3. This angular setting does not is not necessary if the housings 5 are made circumferentially.
  • the wheel produced in FIGS. 2a and 2b comprises a hub 1 provided with blades 3 in which the blades 3 are produced with a flange 6 at their end situated at the periphery of the hub 1.
  • the flange 2 is produced with a diameter D such that it can be kept clamped between said flanges 6.
  • the hub 1 is heated, the flange 2 is placed between the flanges 6 and the tightening occurs during cooling of the hub 1.
  • the wheel shown in Figures 3a and 3b is similar to that shown in Figures 2a and 2b except that the flanges 6 of the blades 3 are interconnected so as to form a rim 7 in which the flange 2 can be held tight.
  • the tightening of the flange 2 is thus carried out over the entire circumference of the flange instead of being exerted only at the level of the blades 3 as in the mode of FIG. 2.
  • the closed wheel is produced, it is closed not only by the flange 2 but also by the rim 7 which in fact makes an extension of the flange 2.
  • the wheel is closed only up to the diameter D.
  • the wheel shown in Figures 3a and 3b can therefore be used for compression stages more efficient than those for which one uses for example a wheel as shown in Figures 2a and 2b.
  • the flange 2 has peripheral flanges 8 extended by a rim 9 such that the hub 1 and the blades 3 carried by the hub 1 can be kept tight respectively between the rim 9 and the flanges 8.
  • This wheel is quite similar to the wheel shown in FIGS. 3a and 3b except that in this case, the flanges and the rim are carried by the flange 2 in order to enclose the hub 1 at instead of being carried by the hub 1 in order to enclose the flange 2.
  • the flanges 8 are of course located only at the level of the blades 3 while the rim 9 constitutes a circumference without discontinuity.
  • flanges 8 in fact constitute extensions of the blades 3 over the largest diameters of the wheel, such a wheel can have the same applications as the wheel described in the example of FIGS. 3a and 3b.
  • An angular setting is also necessary in order to allow the correspondence between the flanges 8 and the blades 3.
  • the wheels produced by the process according to the present invention give very satisfactory results. They are not likely to deteriorate during operation, even if they are subjected to vibrations when the pressure is high.
  • the minimum tightening of 2 ° which must exist between the hub and the flange of a centrifugal wheel produced in accordance with Figures 3a and 3b, with an outside diameter of 520 mm and intended to rotate at 13,115 rpm ( conventional range for a centrifugal compressor) is very easily achieved by the method according to the invention.
  • One or the other of the variants of the method according to the invention can be chosen, according to the constraints that the wheel must support: the mode of FIG. 1 is for example very resistant to vibrations and can be used for high pressures. .
  • the process for producing the wheels according to the invention is simple and rapid: only heating between 200 and 300 ° C. of the flange or of the hub is necessary; a stress relieving treatment is avoided.
  • the assembly of the wheel does not require the presence of personnel as qualified as for a welded wheel and its assembly is very fast. The time taken to produce the wheels is therefore short and the cost price is not very high.
  • machining of the means provided on each of the discs to cooperate with corresponding means of the other disc in order to allow hooping is carried out in a simple manner: for example to produce the lugs and the housings of the wheel mode shown in the figure 1, digital control is used: the same strip is used to produce on the one hand the tenons 4 of the blades 3 and the housings formed in the flange 2. It is of course necessary to provide for the housings 5 slightly offset with respect to the tenons 4, for the purpose of tightening.
  • the production method according to the invention as well as the wheels obtained by this process can be used for all pumps or other centrifugal or centripetal machines in which the radial flow path of the fluid is closed, without limitation.
  • the blades 3 are integral with the hub 1 before shrinking but the blades 3 can also be integral with the flange 1 or be made in two parts, one integral with the hub 1 and the other integral with the flange 2, without departing from the scope of the invention.

Abstract

1. Process for constructing a closed bladed wheel, in which there are prepared a first disc (1) forming a hub and a second disc (2) or end plate by equipping them with blades (3) and the two discs (1 and 2) equipped with blades (3) are secured to one another, and there are provided on one of the discs (1 and 2) projecting elements (4, 6, 7, 8, 9) which are capable of cooperating with corresponding elements (2, 5) on the other disc which are suitable for receiving the projecting elements (4, 6, 7, 8, 9) with clamping, and the discs (1 and 2) are assembled so as to cause the projecting elements (4, 6, 7, 8, 9) of one disc to engage with the elements (2, 5) of the other disc, characterized in that the clamping is carried out by means of a shrinking on which is obtained by previously heating one of the two discs (1 or 2).

Description

La présente invention concerne la réalisation d'une roue à aubes centrifuge ou centripète fermée. Elle s'applique en particulier aux roues de pompes ou d'autres machines centrifuges ou centripètes dont la veine d'écoulement radial du fluide est fermée.The present invention relates to the production of a closed centrifugal or centripetal impeller. It applies in particular to the wheels of pumps or other centrifugal or centripetal machines in which the radial flow path of the fluid is closed.

Plus particulièrement, l'invention concerne une roue à aubes conforme au préambule de la revendication 1.More particularly, the invention relates to an impeller in accordance with the preamble of claim 1.

Les compresseurs centrifuges sont constitués d'un arbre portant une ou plusieurs roues destinées à comprimer le gaz qui traverse le compresseur. Les roues comportent un disque formant moyeu pour le montage sur l'arbre et des aubes fixées sur le disque qui créent un canal d'écoulement pour le gaz. Le gaz, aspiré au niveau de l'arbre, remonte le long du disque, entraîné en rotation par les aubes, jusqu'au diamètre extérieur du disque, en ayant reçu de la part de la roue une énergie cinétique. La transformation à la sortie de la roue de l'énergie cinétique en énergie de pression correspond à là compression.Centrifugal compressors consist of a shaft carrying one or more wheels intended to compress the gas which passes through the compressor. The wheels have a hub disc for mounting on the shaft and vanes attached to the disc which create a flow channel for the gas. The gas, sucked in at the level of the shaft, rises along the disc, driven in rotation by the blades, up to the outside diameter of the disc, having received kinetic energy from the wheel. The transformation at the exit of the wheel from kinetic energy into pressure energy corresponds to compression.

Afin d'améliorer le guidage du fluide dans sa traversée de la roue, les constructeurs savent que l'on peut installer un flasque, fixé aux aubes sur la face avant de la roue, créant un canal fermé donc sans fuite avec les canaux voisins. Ceci augmente le rendement et d'autant plus que le débit à comprimer est faible.In order to improve the guidance of the fluid in its crossing of the wheel, the manufacturers know that it is possible to install a flange, fixed to the blades on the front face of the wheel, creating a closed channel therefore without leakage with the neighboring channels. This increases the yield and all the more that the flow rate to be compressed is low.

Le mode de fabrication habituel de ces roues, dites bidimensionnellest peut consister à fraiser les aubes dans le moyeu, et à rapporter le flasque par soudure sur la face latérale des aubes. Les aubes peuvent être également usinées dans le flasque, celui-ci étant ensuite rapporté par soudure sur le moyeu. Elles peuvent être aussi réalisées en deux parties, l'une des parties étant usinée dans le moyeu et l'autre dans le flasque, le flasque et le moyeu étant ensuite rendus solidaires l'un de l'autre par soudure. Dans tous ces modes de réalisation, c'est la soudure qui est utilisée pour solidariser les divers éléments de la roue. On pourra se reporter à titre d'exemple au brevet français n° 2 312 671.The usual method of manufacturing these wheels, called bidimensional, can consist of milling the blades in the hub, and attaching the flange by welding to the side face of the blades. The blades can also be machined in the flange, the latter then being attached by welding to the hub. They can also be made in two parts, one of the parts being machined in the hub and the other in the flange, the flange and the hub then being made integral with one another by welding. In all these embodiments, it is the weld which is used to secure the various elements of the wheel. As an example, reference may be made to French Patent No. 2,312,671.

Toutefois la réalisation de roues fermées par soudure présente un certain nombre d'inconvénients : ce procédé nécessite non seulement une soudure mais aussi un traitement thermique de détensionnement et un contrôle de la qualité de la soudure réalisée ; il nécessite donc une main- d'oeuvre qualifiée et le délai de réalisation d'une telle roue est long et son prix de revient est élevé.However, the production of closed wheels by welding has a certain number of drawbacks: this process requires not only a weld but also a stress relieving heat treatment and a quality control of the weld produced; it therefore requires skilled labor and the time taken to produce such a wheel is long and its cost is high.

D'autres procédés, utilisant des moyens de liaison tels que vis ou rivets présentent aussi des inconvénients : la réalisation des trous puis le vissage ou le rivetage posent des problèmes de positionnement de la roue et demandent un délai de réalisation assez long. En outre, en cours de fonctionnement, quand la roue est soumise à des vibrations, celles-ci étant d'autant plus fortes que la pression est élevée, la roue risque de se détériorer si les vis et rivets ne restent pas dans leur position initiale.Other methods, using connecting means such as screws or rivets also have drawbacks: making the holes and then screwing or riveting pose problems with positioning the wheel and require a fairly long lead time. In addition, during operation, when the wheel is subjected to vibrations, these being all the stronger as the pressure is high, the wheel may deteriorate if the screws and rivets do not remain in their initial position. .

A titre d'exemple, le document US-A-1 919970 décrit la réalisation d'une roue à aubes fermée dans laquelle un disque, muni d'aubes, formant moyeu, est assemblé avec deux disques munis d'aubes et formant flasques, au moyen d'une série de vis.By way of example, document US-A-1 919970 describes the production of a closed paddle wheel in which a disc, provided with blades, forming a hub, is assembled with two discs provided with blades and forming flanges, by means of a series of screws.

L'invention remédie aux inconvénients des procédés de réalisation de roues précités. Elle vise un procédé simple, rapide, permettant d'obtenir des roues de très bonne qualité susceptibles de supporter même des conditions difficiles de fonctionnement. L'invention vise également une roue obtenue au moyen de ce procédé.The invention overcomes the drawbacks of the above-mentioned methods of making wheels. It aims at a simple, rapid process, making it possible to obtain very good quality wheels capable of withstanding even difficult operating conditions. The invention also relates to a wheel obtained by means of this method.

Les avantages sont obtenus, selon l'invention, par l'étape définie dans la partie caractérisante de la revendication 1.The advantages are obtained, according to the invention, by the step defined in the characterizing part of claim 1.

Dans une première variante; préférée, du procédé selon l'invention, on munit d'aubes un seul des deux disques en prévoyant sur celles-ci des tenons et l'on prévoit des logements correspondants à ces tenons dans l'épaisseur de l'autre disque. De préférence, on prévoit des logements ponctuels et l'on réalise un calage angulaire avant frettage afin de permettre là mise en regard des tenons avec les logements correspondants.In a first variant; preferred, of the process according to the invention, only one of the two discs is provided with vanes by providing studs on them and provision is made for housings corresponding to these studs in the thickness of the other disc. Preferably, punctual housings are provided and an angular setting is carried out before shrinking in order to allow the pins to be compared with the corresponding housings.

Dans une deuxième variante du procédé selon l'invention, on munit d'aubes chacun des deux disques, en prévoyant des tenons sur les aubes situées sur l'un des disques et des logements correspondants sur les aubes situées sur l'autre disque et l'on réalise un calage angulaire avant frettage afin de permettre la mise en regard de chaque aube avec une aube correspondante de l'autre disque. 'In a second variant of the method according to the invention, vanes are provided on each of the two discs, by providing pins on the vanes located on one of the discs and corresponding housings on the vanes located on the other disc and l 'an angular setting is carried out before shrinking in order to allow each blade to be compared with a corresponding blade of the other disc. ''

Dans une troisième variante du procédé selon l'invention, on munit d'aubes un seul des deux disques et l'on réalise ces aubes avec un rebord à leur extrémité située à la périphérie du disque, et l'on réalise- le second disque avec un diamètre tel que le second disque puisse être maintenu serré entre lesdits rebords.In a third variant of the method according to the invention, only one of the two discs is provided with vanes and these vanes are produced with a flange at their end situated at the periphery of the disc, and the second disc is produced. with a diameter such that the second disc can be kept clamped between said flanges.

Dans un mode particulier de la troisième variante, lesdits rebords sont reliés entre eux de façon à former une jante dans laquelle le second disque peut être maintenu serré.In a particular embodiment of the third variant, said flanges are interconnected so as to form a rim in which the second disc can be held tight.

Dans une quatrième variante du procédé selon l'invention, on munit d'aubes un seul des deux disques et l'on réalise le deuxième disque avec des rebords périphériques prolongés par une jante tels que le premier disque et les aubes puissent être maintenus serrés respectivement entre la jante et les rebords et l'on réalise un calage angulaire avant frettage afin de permettre la mise en regard de chaque aube avec un rebord corespondant du deuxième disque.In a fourth variant of the method according to the invention, one of the two discs is provided with vanes and the second disc is produced with peripheral flanges extended by a rim such that the first disc and the vanes can be held tight respectively between the rim and the edges and an angular setting is carried out before shrinking in order to allow each blade to be compared with a corresponding edge of the second disc.

L'invention concerne également une roue à aubes fermée réalisée au moyen de l'une quelconque des variantes précitées du procédé selon l'invention.The invention also relates to a closed paddle wheel produced by means of any one of the abovementioned variants of the method according to the invention.

Afin que l'invention soit mieux comprise, celle-ci va être décrite de façon plus détaillée dans quatre modes de réalisation de l'invention décrits uniquement à titre d'exemples et représentés sur les dessins annexés.

  • La figure 1a représente en coupe axiale une roue obtenue par une première variante du procédé selon l'invention. Cette figure est une coupe selon A-A de la figure 1c.
  • La figure 1c est une vue de dessus de la roue représentée sur la figure 1a.
  • La figure 1b représente les éléments de la roue de la figure 1a avant frettage.
  • La figure 2a représente, de façon analogue à la figure 1a, une roue obtenue par une deuxième variante du procédé selon l'invention.
  • La figure 2b représente de façon analogue à la figure 1b, les éléments de la roue de la figure 2a avant frettage.
  • Les figures 3a et 3b représentent, de façon analogue aux figures la et 1b, une roue obtenue par une troisième variante du procédé selon l'invention.
  • Les figures 4a et 4b représentent, de façon analogue aux figures 1a et 1b, une roue obtenue par une quatrième variante du procédé selon l'invention.
In order for the invention to be better understood, it will be described in more detail in four embodiments of the invention described only by way of examples and shown in the accompanying drawings.
  • Figure 1a shows in axial section a wheel obtained by a first variant of the method according to the invention. This figure is a section along AA of Figure 1c.
  • Figure 1c is a top view of the wheel shown in Figure 1a.
  • Figure 1b shows the elements of the wheel of Figure 1a before hooping.
  • FIG. 2a represents, analogously to FIG. 1a, a wheel obtained by a second variant of the method according to the invention.
  • Figure 2b shows similarly to Figure 1b, the elements of the wheel of Figure 2a before shrinking.
  • Figures 3a and 3b show, similarly to Figures la and 1b, a wheel obtained by a third variant of the method according to the invention.
  • Figures 4a and 4b show, similarly to Figures 1a and 1b, a wheel obtained by a fourth variant of the method according to the invention.

Sur l'ensemble de ces figures, la roue est constituée de deux disques, un disque 1 formant moyeu et un deuxième disque 2 également appelé flasque. Les deux disques 1 et 2 sont munis chacun d'un alésage central, l'et 2', pour permettre le montage de la roue sur un arbre non représenté de la machine sur laquelle la roue est destinée à être utilisée. Des aubes 3 sont destinées à créer un canal d'écoulement pour le gaz qui, aspiré au niveau de l'arbre, c'est-à-dire des alésages, remonte le long des disques 1 et 2, entraîné en rotation par les aubes 3, jusqu'au diamètre extérieur des disques 1 et 2 en ayant reçu de la part de la roue une énergie cinétique. Les disques 1 et 2 réalisent avec les aubes 3 des canaux qui sont chacun isolés des canaux voisins.In all of these figures, the wheel consists of two discs, a disc 1 forming a hub and a second disc 2 also called a flange. The two discs 1 and 2 are each provided with a central bore, the and 2 ', to allow the mounting of the wheel on a shaft not shown of the machine on which the wheel is intended to be used. Blades 3 are intended to create a flow channel for the gas which, drawn in at the level of the shaft, that is to say bores, rises along the disks 1 and 2, driven in rotation by the blades 3, to the outside diameter of the discs 1 and 2 having received kinetic energy from the wheel. The discs 1 and 2 produce with the blades 3 channels which are each isolated from the neighboring channels.

Pour réaliser une roue représentée sur les figures 1a, .2a, 3a ou 4a, on prépare tout d'abord deux disques, un moyeu 1 et un flasque 2, comme représentés sur les figures 1b, 2b, 3b et 4b. On prépare ces disques en les munissant d'aubes 3. Sur tous les exemples représentés, c'est le moyeu 1 qui porte les aubes 3. De préférence le moyeu 1 et les aubes 3 ont été usinés dans un même bloc de métal ; on pourrait aussi souder les aubes 3 sur le moyeu 1, mais comme nous l'avons expliqué plus haut, le soudage présente certains inconvénients que nous cherchons précisément à éviter.To make a wheel shown in Figures 1a, .2a, 3a or 4a, two discs are first prepared, a hub 1 and a flange 2, as shown in Figures 1b, 2b, 3b and 4b. These discs are prepared by providing them with blades 3. In all the examples shown, it is the hub 1 which carries the blades 3. Preferably the hub 1 and the blades 3 have been machined from the same block of metal; we could also weld the blades 3 on the hub 1, but as we explained above, welding has certain drawbacks that we are specifically trying to avoid.

Le moyeu 1 porteur d'aubes 3 et le flasque 2 sont réalisés de telle façon qu'ils puissent être rendus solidaires l'un de l'autre afin de constituer une roue fermée, par frettage. Dans ce but, chacun des deux disques 1 et 2 est muni de moyens susceptibles de coopérer avec des moyens correspondants de l'autre disque.The hub 1 bearing blades 3 and the flange 2 are produced in such a way that they can be made integral with one another in order to constitute a closed wheel, by hooping. For this purpose, each of the two discs 1 and 2 is provided with means capable of cooperating with corresponding means of the other disc.

Ainsi sur la roue représentée sur les figures 1a, 1b, 1c. les aubes 3 portées par le moyeu 1 sont munies de tenons 4 correspondant à des logements 5 usinés dans l'épaisseur du flasque 2. L'usinage des tenons 4 et des logements 5 peut être pratiqué circonférenciellement, par tournage, ce qui assure une bonne précision et permet d'obtenir un coût de réalisation peu élevé. Les logements 5 peuvent aussi être ponctuels, c'est-à-dire réalisés par freisage uniquement au niveau des aubes 3 : on assure ainsi une continuité du flasque 2 et de l'écoulement du gaz sur celui-ci.Thus on the wheel shown in Figures 1a, 1b, 1c. the blades 3 carried by the hub 1 are provided with pins 4 corresponding to housings 5 machined in the thickness of the flange 2. The machining of the pins 4 and of the housings 5 can be practiced circumferentially, by turning, which ensures good precision and allows a low production cost to be obtained. The housings 5 can also be punctual, that is to say produced by braking only at the level of the vanes 3: this ensures continuity of the flange 2 and of the flow of gas thereon.

Pour réaliser le frettage, on chauffe préalablement le flasque 2 à une température permettant sa dilatation mais ne modifiant pas sa structure, puis l'on vient poser le flasque 2 sur le moyeu 1 en emboîtant les tenons 4 dans les logements 5. Au cours du refroidissement du flasque 2 il se produit un serrage au niveau des tenons 4 et des logements 5 : le moyeu 1 et le flasque 2 sont rendus solidaires l'un de l'autre. Bien sûr, les logements 5 et les tenons 4 sont prévus de façon à pouvoir s'emboîter quand le flasque 2 est chauffé et à se trouver sous contrainte quand le flasque 2 est refroidi ; cette contrainte doit pouvoir être supportée par les métaux constituant le moyeu 1 et le flasque 2 aussi bien au repos qu'en fonctionnement. - To make the hooping, the flange 2 is previously heated to a temperature allowing its expansion but not modifying its structure, then the flange 2 is placed on the hub 1 by fitting the pins 4 into the housings 5. During the cooling of the flange 2 there is a tightening at the level of the pins 4 and of the housings 5: the hub 1 and the flange 2 are made integral with one another. Of course, the housings 5 and the pins 4 are provided so as to be able to fit together when the flange 2 is heated and to be under stress when the flange 2 is cooled; this constraint must be able to be supported by the metals constituting the hub 1 and the flange 2 both at rest and in operation. -

Si les logements 5 sont ponctuels, il est nécessaire de prévoir un calage angulaire lors du positionnement du flasque 2 sur le disque 1, afin que les logements 5 puissent s'emboîter dans les tenons 4 situés sur les aubes 3. Ce calage angulaire n'est pas nécessaire si les logements 5 sont réalisés circonférenciellement.If the housings 5 are punctual, it is necessary to provide an angular setting when positioning the flange 2 on the disc 1, so that the housings 5 can fit into the studs 4 located on the blades 3. This angular setting does not is not necessary if the housings 5 are made circumferentially.

La roue réalisée sur les figures 2a et 2b comporte un moyeu 1 muni d'aubes 3 dans lequel les aubes 3 sont réalisées avec un rebord 6 à leur extrémité située à la périphérie du moyeu 1. Le flasque 2 est réalisé avec un diamètre D tel qu'il puisse être maintenu serré entre lesdits rebords 6. Le moyeu 1 est chauffé, le flasque 2 est placé entre les rebords 6 et le serrage se produit lors du refroidissement du moyeu 1.The wheel produced in FIGS. 2a and 2b comprises a hub 1 provided with blades 3 in which the blades 3 are produced with a flange 6 at their end situated at the periphery of the hub 1. The flange 2 is produced with a diameter D such that it can be kept clamped between said flanges 6. The hub 1 is heated, the flange 2 is placed between the flanges 6 and the tightening occurs during cooling of the hub 1.

La roue représentée sur les figures 3a et 3b est analogue à celle représentée sur les figures 2a et 2b sauf que les rebords 6 des aubes 3 sont reliés entre eux de façon à former une jante 7 dans laquelle le flasque 2 peut être maintenu serré. Le serrage du flasque 2 s'effectue ainsi sur toute la circonférence du flasque au lieu de ne s'exercer qu'au niveau des aubes 3 comme dans le mode de la figure 2. En outre, une fois que la roue fermée est réalisée, celle-ci se trouve fermée non seulement par le flasque 2 mais également par la jante 7 qui réalise en fait un prolongement du flasque 2. Ainsi l'écoulement du gaz est conservé sur les plus grands diamètres de la roue. Au contraire, dans le mode de réalisation des figures 2a et 2b, la roue ne se trouve fermée que jusqu'au diamètre D. La roue représentée sur les figures 3a et 3b peut par conséquent être utilisée pour des étages de compression plus performants que ceux pour lesquels on utilise par exemple une roue telle que représentée sur les figures 2a et 2b.The wheel shown in Figures 3a and 3b is similar to that shown in Figures 2a and 2b except that the flanges 6 of the blades 3 are interconnected so as to form a rim 7 in which the flange 2 can be held tight. The tightening of the flange 2 is thus carried out over the entire circumference of the flange instead of being exerted only at the level of the blades 3 as in the mode of FIG. 2. In addition, once the closed wheel is produced, it is closed not only by the flange 2 but also by the rim 7 which in fact makes an extension of the flange 2. Thus the gas flow is preserved over the largest diameters of the wheel. On the contrary, in the embodiment of Figures 2a and 2b, the wheel is closed only up to the diameter D. The wheel shown in Figures 3a and 3b can therefore be used for compression stages more efficient than those for which one uses for example a wheel as shown in Figures 2a and 2b.

Sur les figures 4a et 4b, le flasque 2 comporte des rebords périphériques 8 prolongés par une jante 9 tels que le moyeu 1 et les aubes 3 portées par le moyeu 1 puissent être maintenus serrés respectivement entre la jante 9 et les rebords 8. Cette roue est assez analogue à la roue représentée sur les figures 3a et 3b sauf que dans ce cas, les rebords et la jante sont portés par le flasque 2 afin d'enserrer le moyeu 1 au lieu d'être portés par le moyeu 1 afin d'enserrer le flasque 2. Les rebords 8 ne sont bien sûr situés qu'au niveau des aubes 3 alors que la jante 9 constitue une circonférence sans discontinuité. Comme les rebords 8 constituent en fait des prolongements des aubes 3 sur les plus grands diamètres de la roue, une telle roue peut avoir les mêmes applications que la roue décrite dans l'exemple des figures 3a et 3b. Un calage angulaire est également nécessaire afin de permettre la correspondance entre les rebords 8 et les aubes 3.In FIGS. 4a and 4b, the flange 2 has peripheral flanges 8 extended by a rim 9 such that the hub 1 and the blades 3 carried by the hub 1 can be kept tight respectively between the rim 9 and the flanges 8. This wheel is quite similar to the wheel shown in FIGS. 3a and 3b except that in this case, the flanges and the rim are carried by the flange 2 in order to enclose the hub 1 at instead of being carried by the hub 1 in order to enclose the flange 2. The flanges 8 are of course located only at the level of the blades 3 while the rim 9 constitutes a circumference without discontinuity. As the flanges 8 in fact constitute extensions of the blades 3 over the largest diameters of the wheel, such a wheel can have the same applications as the wheel described in the example of FIGS. 3a and 3b. An angular setting is also necessary in order to allow the correspondence between the flanges 8 and the blades 3.

Les roues réalisées par le procédé conforme à la présente invention donnent des résultats très satisfaisants. Elles ne risquent pas de se détériorer en fonctionnement, même si elles sont soumises à des vibrations lorsque la pression est forte. A titre d'exemple, le serrage minimal de 2° qui doit exister entre le moyeu et le flasque d'une roue centrifuge réalisée conformément aux figures 3a et 3b, de diamètre extérieur 520 mm et destinée à tourner à 13 115 tours/mn (gamme classique pour un compresseur centrifuge) est réalisée très facilement par le procédé selon l'invention. On peut choisir l'une ou l'autre des variantes du procédé selon l'invention, en fonction des contraintes que la roue doit supporter : le mode de la figure 1 est par exemple très résistant aux vibrations et peut être utilisé pour de fortes pressions.The wheels produced by the process according to the present invention give very satisfactory results. They are not likely to deteriorate during operation, even if they are subjected to vibrations when the pressure is high. For example, the minimum tightening of 2 ° which must exist between the hub and the flange of a centrifugal wheel produced in accordance with Figures 3a and 3b, with an outside diameter of 520 mm and intended to rotate at 13,115 rpm ( conventional range for a centrifugal compressor) is very easily achieved by the method according to the invention. One or the other of the variants of the method according to the invention can be chosen, according to the constraints that the wheel must support: the mode of FIG. 1 is for example very resistant to vibrations and can be used for high pressures. .

En outre, comme nous l'avons expliqué plus haut, on préfère pour les fortes pressions les modes de réalisation de roues dans lesquelles le flasque 2 est fermé même sur le plus grand diamètre de la roue.In addition, as we explained above, we prefer for high pressures the embodiments of wheels in which the flange 2 is closed even on the largest diameter of the wheel.

Le procédé de réalisation des roues selon l'invention est simple et rapide : seul un chauffage entre 200 et 300 °C du flasque ou du moyeu est nécessaire ; un traitement thermique de détensionnement est évité. Le montage de la roue ne requiert pas la présence d'un personnel aussi qualifié que pour une roue soudée et son montage est très rapide. Le délai de réalisation des roues est donc court et le prix de revient n'est pas très élevé.The process for producing the wheels according to the invention is simple and rapid: only heating between 200 and 300 ° C. of the flange or of the hub is necessary; a stress relieving treatment is avoided. The assembly of the wheel does not require the presence of personnel as qualified as for a welded wheel and its assembly is very fast. The time taken to produce the wheels is therefore short and the cost price is not very high.

L'usinage des moyens prévus sur chacun des disques pour coopérer avec des moyens correspondants de l'autre disque afin de permettre le frettage est réalisé de façon simple : par exemple pour réaliser les tenons et les logements du mode de la roue représenté sur la figure 1, on utilise la commande numérique : une même bande est utilisée pour réaliser d'une part les tenons 4 des aubes 3 et les logements ménagés dans le flasque 2. Il faut bien sûr prévoir de réaliser les logements 5 légèrement décalés par rapport aux tenons 4, en vue de réaliser un serrage.The machining of the means provided on each of the discs to cooperate with corresponding means of the other disc in order to allow hooping is carried out in a simple manner: for example to produce the lugs and the housings of the wheel mode shown in the figure 1, digital control is used: the same strip is used to produce on the one hand the tenons 4 of the blades 3 and the housings formed in the flange 2. It is of course necessary to provide for the housings 5 slightly offset with respect to the tenons 4, for the purpose of tightening.

Le procédé de réalisation selon l'invention ainsi que les roues obtenues par ce procédé peuvent être utilisés pour toutes pompes ou autres machines centrifuges ou centripètes dont la veine d'écoulement radial du fluide est fermée, sans limitation.The production method according to the invention as well as the wheels obtained by this process can be used for all pumps or other centrifugal or centripetal machines in which the radial flow path of the fluid is closed, without limitation.

Ainsi, on a décrit des modes de réalisation dans lesquels les aubes 3 sont solidaires du moyeu 1 avant frettage mais les aubes 3 peuvent aussi être solidaires du flasque 1 ou être réalisées en deux parties, l'une solidaire du moyeu 1 et l'autre solidaire du flasque 2, sans que l'on sorte du cadre de l'invention.Thus, there have been described embodiments in which the blades 3 are integral with the hub 1 before shrinking but the blades 3 can also be integral with the flange 1 or be made in two parts, one integral with the hub 1 and the other integral with the flange 2, without departing from the scope of the invention.

Ainsi on pourrait concevoir une roue dans laquelle, avant frettage, le moyeu 1 et le flasque 2 seraient tous les deux munis d'aubes ou plus exactement de demi-aubes, comme dans le mode représenté sur les figures 5a et 5b du brevet français n° 2 312 671 cité plus haut. On prévoie- rait sur les aubes situées sur l'un des disques, par exemple sur le moyeu, des tenons semblables aux tenons 4 de nos figures 1a, 1b, 1c et sur les aubes situées sur le flasque 2 des logements correspondants analogues aux logements 5 de ces mêmes figures. On procéderait à un calage angulaire afin de placer les aubes 3 du moyeu 1 en correspondance avec les aubes du flasque 2 et on réaliserait le frettage comme pour le mode de réalisation de notre figure 1.Thus one could design a wheel in which, before hooping, the hub 1 and the flange 2 would both be provided with blades or more exactly with half-blades, as in the mode represented in FIGS. 5a and 5b of French patent n ° 2 312 671 cited above. We would provide on the blades located on one of the discs, for example on the hub, pins similar to the pins 4 of our figures 1a, 1b, 1c and on the blades located on the flange 2 of the corresponding housings similar to the housings 5 of these same figures. An angular setting would be carried out in order to place the blades 3 of the hub 1 in correspondence with the blades of the flange 2 and the hooping would be carried out as for the embodiment of our figure 1.

On pourrait également réaliser le frettage sans chauffage préalable de l'un des deux disques mais en utilisant une presse.One could also carry out hooping without first heating one of the two discs but using a press.

Claims (7)

1. Process for constructing a closed bladed wheel, in which there are prepared a first disc (1) forming a hub and a second disc (2) or end plate by equipping them with blades (3) and the two discs (1 and 2) equipped with blades (3) are secured to one another, and there are provided on one of the discs (1 and 2) projecting elements (4, 6, 7, 8, 9) which are capable of cooperating with corresponding elements (2, 5) on the other disc which are suitable for receiving the projecting elements (4, 6, 7, 8, 9) with clamping, and the discs (1 and 2) are assembled so as to cause the projecting elements (4, 6, 7, 8, 9) of one disc to engage with the elements (2, 5) of the other disc, characterized in that the clamping is carried out by means of a shrinking on which is obtained by previously heating one of the two discs (1 or 2).
2. Process according to Claim 1, characterized in that only one of the two discs is equipped with blades (3), providing these with studs (4), and in that receivers (5) corresponding to these studs (4) are provided in the thickness of the other disc.
3. Process according to Claim 2, characterized in that punctiform receivers (5) are provided, and in that an angular adjustment is carried out before shrinking on in order to enable the studs (4) to be placed opposite the corresponding receivers (5).
4. Process according to Claim 1, characterized in that each of the two discs (1) and (2) is equipped with blades (3), providing studs (4) on the blades (3) located on one of the discs (1 or 2) and corresponding receivers on the blades (3) located on the other disc (1 or 2), and corresponding receivers on the blades (3) located on the other disc (1 or 2), and in that an angular adjustment is carried out before shrinking on in order to enable each blade (3) to be placed opposite a corresponding blade (3) of the other disc.
5. Process according to either of Claims 1 or 2, characterized in that only one of the two discs is equipped with blades, and in that these blades are constructed with a shoulder (6) at their end located at the periphery of the disc, and in that the second disc is constructed with a diameter (D) such that the second disc can be held clamped between the shoulders (6).
6. Process according to Claim 5, characterized in that the shoulders (6) are connected to one another so that they form a rim (7) in which the second disc can be held clamped.
7. Process according to Claim 1, characterized in that only one of the two discs is equipped with blades (3), and in that the second disc is constructed with peripheral shoulders (8) which are extended by a rim (9) such that the first disc and the blades (3) can be held clamped respectively between the rim (9) and the shoulders (8), and in that an angular adjustment is carried out before shrinking on in order to enable each blade (3) to be placed opposite a corresponding shoulder (8) of the second disc.
EP85400203A 1984-02-10 1985-02-07 Production method for a closed impeller Expired EP0153221B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT85400203T ATE37589T1 (en) 1984-02-10 1985-02-07 MANUFACTURING PROCESS OF A CLOSED IMPELLER.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8402047A FR2559544B1 (en) 1984-02-10 1984-02-10 PROCESS FOR PRODUCING A CLOSED BLADE WHEEL AND WHEEL OBTAINED BY MEANS OF THIS PROCESS
FR8402047 1984-02-10

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EP0153221A1 EP0153221A1 (en) 1985-08-28
EP0153221B1 true EP0153221B1 (en) 1988-09-28

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EP85400203A Expired EP0153221B1 (en) 1984-02-10 1985-02-07 Production method for a closed impeller

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AT (1) ATE37589T1 (en)
DE (1) DE3565301D1 (en)
FR (1) FR2559544B1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2533605C2 (en) * 2013-03-12 2014-11-20 Открытое акционерное общество "Ракетно-космическая корпорация "Энергия" имени С.П. Королева" Centrifugal impeller

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4113831A1 (en) * 1991-04-27 1992-10-29 Klein Schanzlin & Becker Ag DIVIDED WHEEL
DE59208865D1 (en) * 1992-12-08 1997-10-09 Asea Brown Boveri Stabilizing device for expanding the map of a compressor
US5328332A (en) * 1993-05-25 1994-07-12 Chiang Swea T Wheel fan of range hood
US5588803A (en) * 1995-12-01 1996-12-31 General Motors Corporation Centrifugal impeller with simplified manufacture
DE19746850A1 (en) * 1997-10-23 1999-04-29 Wilo Gmbh Impeller made of sheet metal
US6523995B2 (en) * 2001-03-23 2003-02-25 Chemineer, Inc. In-tank mixing system and associated radial impeller
CN101526088A (en) * 2008-03-03 2009-09-09 普拉德研究及开发股份有限公司 Impeller for centrifugal pump
RU2568358C1 (en) * 2014-05-22 2015-11-20 Открытое акционерное общество "Ракетно-космическая корпорация "Энергия" имени С.П. Королева" Centrifugal impeller
GB2574221A (en) * 2018-05-30 2019-12-04 Cnc Subcon Services Ltd Impeller and method of manufacture
RU190999U1 (en) * 2019-04-24 2019-07-18 Акционерное общество (АО) "Научно-исследовательский институт "Лопастных машин" ("НИИ ЛМ") WORKING WHEEL CENTRIFUGAL PUMP
DE102019206548A1 (en) * 2019-05-07 2020-11-12 Mahle International Gmbh Fluid pump
RU2731465C1 (en) * 2019-11-07 2020-09-03 Акционерное общество "Гидрогаз" (АО "Гидрогаз") Centrifugal pump impeller (embodiments)

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1919970A (en) * 1933-02-07 1933-07-25 Gen Electric Impeller
FR2312671A1 (en) * 1975-05-30 1976-12-24 Creusot Loire PROCESS FOR MAKING A CENTRIFUGAL BLADE WHEEL AND WHEEL OBTAINED BY THIS PROCESS

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2533605C2 (en) * 2013-03-12 2014-11-20 Открытое акционерное общество "Ракетно-космическая корпорация "Энергия" имени С.П. Королева" Centrifugal impeller

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ATE37589T1 (en) 1988-10-15
FR2559544B1 (en) 1988-07-08
EP0153221A1 (en) 1985-08-28
FR2559544A1 (en) 1985-08-16
DE3565301D1 (en) 1988-11-03

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