EP0015191B1 - Heat exchanger - Google Patents

Heat exchanger Download PDF

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Publication number
EP0015191B1
EP0015191B1 EP80400200A EP80400200A EP0015191B1 EP 0015191 B1 EP0015191 B1 EP 0015191B1 EP 80400200 A EP80400200 A EP 80400200A EP 80400200 A EP80400200 A EP 80400200A EP 0015191 B1 EP0015191 B1 EP 0015191B1
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EP
European Patent Office
Prior art keywords
tubes
heat exchanger
tube
exchanger according
shell
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP80400200A
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German (de)
French (fr)
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EP0015191A1 (en
Inventor
Marcel Robin
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Commissariat a lEnergie Atomique et aux Energies Alternatives CEA
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Commissariat a lEnergie Atomique CEA
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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22—STEAM GENERATION
    • F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
    • F22B37/00—Component parts or details of steam boilers
    • F22B37/02—Component parts or details of steam boilers applicable to more than one kind or type of steam boiler
    • F22B37/10—Water tubes; Accessories therefor
    • F22B37/12—Forms of water tubes, e.g. of varying cross-section
    • F22B37/125—Bifurcates
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22—STEAM GENERATION
    • F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
    • F22B1/00—Methods of steam generation characterised by form of heating method
    • F22B1/02—Methods of steam generation characterised by form of heating method by exploitation of the heat content of hot heat carriers
    • F22B1/06—Methods of steam generation characterised by form of heating method by exploitation of the heat content of hot heat carriers the heat carrier being molten; Use of molten metal, e.g. zinc, as heat transfer medium
    • F22B1/063—Methods of steam generation characterised by form of heating method by exploitation of the heat content of hot heat carriers the heat carrier being molten; Use of molten metal, e.g. zinc, as heat transfer medium for metal cooled nuclear reactors
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22—STEAM GENERATION
    • F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
    • F22B37/00—Component parts or details of steam boilers
    • F22B37/02—Component parts or details of steam boilers applicable to more than one kind or type of steam boiler
    • F22B37/22—Drums; Headers; Accessories therefor
    • F22B37/221—Covers for drums, collectors, manholes or the like
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22—STEAM GENERATION
    • F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
    • F22B37/00—Component parts or details of steam boilers
    • F22B37/02—Component parts or details of steam boilers applicable to more than one kind or type of steam boiler
    • F22B37/38—Determining or indicating operating conditions in steam boilers, e.g. monitoring direction or rate of water flow through water tubes
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22—STEAM GENERATION
    • F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
    • F22B37/00—Component parts or details of steam boilers
    • F22B37/02—Component parts or details of steam boilers applicable to more than one kind or type of steam boiler
    • F22B37/42—Applications, arrangements, or dispositions of alarm or automatic safety devices
    • F22B37/421—Arrangements for detecting leaks
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22—STEAM GENERATION
    • F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
    • F22B37/00—Component parts or details of steam boilers
    • F22B37/62—Component parts or details of steam boilers specially adapted for steam boilers of forced-flow type
    • F22B37/70—Arrangements for distributing water into water tubes
    • F22B37/74—Throttling arrangements for tubes or sets of tubes
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F27/00—Control arrangements or safety devices specially adapted for heat-exchange or heat-transfer apparatus
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S165/00—Heat exchange
    • Y10S165/001—Heat exchange with alarm, indicator, recorder, test, or inspection means
    • Y10S165/006—Temperature

Definitions

  • the invention relates to an exchanger designed in particular to ensure heat transfer between two circuits of a nuclear power plant.
  • the invention relates in particular to an exchanger such as a steam generator comprising an envelope in which the heat conveyed by a primary fluid is transferred to a secondary fluid so as to heat and, optionally, to vaporize the latter, the circulating secondary fluid in tubes whose opposite ends open into inlet and outlet manifolds arranged outside the generator casing.
  • Steam generators of this type are used in particular, although not exclusively, in the circuits of nuclear reactors cooled by liquid metal, to ensure heat transfer between a cooling circuit in which a liquid metal, such as sodium, circulates. , and a circuit supplying an electricity production installation in which a liquid such as water circulates.
  • the length of the tubes in which the secondary fluid circulates is adapted to the quality of steam to be produced and often of the order of a hundred meters, and the number of these tubes is relatively large, so as to allow a heat exchange as complete as possible between the liquid sodium which generally constitutes the primary fluid and the water, or the vapor circulating in the tubes, the latter bathing in the liquid sodium.
  • the tightness of the tubes it is imperative to be able to check the tightness of the tubes.
  • Steam generators are known in which the tubes open at each of their ends in a water box and a substantially cylindrical steam box, the inlet and outlet boxes being for example each four in number, while the generator contains approximately 360 tubes, so that approximately 90 tubes open into each of the boxes.
  • Collectors collect the outlets of the water and steam boxes.
  • the tubes open into each of the boxes at one of its ends, while the other end of the box is closed by a removable cover, the dismantling of which allows access to the orifice of each of the tubes opening into this box. Because of the number of tubes opening into each of the boxes, the dimensions of the latter are relatively large, so that they must have tubular plates and thick walls, and the diameter of the cover is relatively large.
  • each box and its cover which is usually achieved by means of an autoclave seal, the diameter of which can reach approximately 420 mm, risks presenting defects during operation.
  • the dimensions of the box which has a relatively large length compared to its diameter, make it quite difficult to locate the tubes and access to a well-defined orifice.
  • the exchanger and the collectors are generally arranged inside an insulating material which it is necessary to dismantle before having access to the tubes.
  • the subject of the invention is an exchanger making it possible to eliminate the drawbacks, mentioned above, of known exchangers, while facilitating access to the orifices of each of the tubes, as well as their sealing, to carry out the necessary measurements or to verify the condition of a flow stabilization device (diaphragm).
  • an exchanger comprising a casing in which the heat conveyed by a primary fluid is transferred to a secondary fluid so as to heat the latter, the secondary fluid circulating in tubes whose opposite ends open into tubular inlet manifolds and outlet disposed outside of the shell of the exchanger and surrounding it at least in part, access to the ends being effected by access devices closed by a removable plug being provided for each of the tubes, each of the access devices being arranged in a part of the tube located between the shell of the exchanger and the corresponding collector.
  • tubular collectors which is also known, makes it possible to significantly reduce the thickness of the walls compared to cylindrical boxes due to the reduction in resulting stresses at the walls for a given internal pressure.
  • realization at each end of the tubes, between the collector and the shell of the exchanger, of an access device closed by a removable plug avoids the sealing problems associated with the large dimensions of the orifice to be closed and to facilitate individual access to each of the tubes, in particular by arranging the access devices outside the insulation, when the shell of the exchanger and the collectors are in an insulation.
  • each of said parts of the tubes has a first straight portion, ending with the access device, and a second portion, forming a T with the straight portion and connecting the latter to the manifold. corresponding.
  • each of said parts of the tubes then extends in a direction substantially normal to the shell of the exchanger.
  • the second portion of each of said parts of the tubes is preferably connected to the straight portion near the corresponding access device.
  • the plug closing the access device arranged in the part of each of the tubes located between the shell of the exchanger and the inlet manifold can then carry a tubular member which extends in the straight portion of said part of the tubes. beyond the connection of the second portion of said part of the tubes, the tubular member being perforated laterally at the level of the second portion and supporting a diaphragm or more generally a device creating a similar pressure drop beyond the latter.
  • the second portion of each of said parts of the tubes forms a dilatation lyre.
  • the rectilinear portion of each of said parts of the tubes is surrounded by an anti-torsion device, one end of which is fixed to the shell of the exchanger and the other end of which has, for example, at least a longitudinal notch into which a finger integral with the rectilinear portion penetrates in the vicinity of the access device, the anti-torsion device further comprising a longitudinal slot through which the second portion of the corresponding tube part passes.
  • each of said parts of the tubes comprises a threaded portion surrounding the access device, onto which is screwed a nut by means of which the corresponding plug is normally pressed in a sealed manner against the device. 'access.
  • At least one of the plugs blocking the access devices carries a temperature measuring device and all of them can be replaced by a sealing control device.
  • the steam generator shown diagrammatically in FIG. 1 is a known generator, intended to be disposed between a cooling circuit of a nuclear reactor cooled by liquid metal and a circuit supplying an installation for producing electricity.
  • a steam generator of this type comprises a casing 10, of generally cylindrical shape, arranged vertically and inside which circulates a primary fluid 12, constituted in particular by a liquid metal such as sodium, which penetrates at the upper end of the casing 10 by inlet orifices 14 and which emerges from the steam generator by an outlet orifice 16 formed at the base of the casing 10.
  • sodium 12 circulates in a circuit of a nuclear reactor and carries the heat coming from the reactions occurring in the core of this reactor.
  • the envelope 10 is sealed and the sodium 12 is placed under an argon atmosphere 18.
  • a number of tubes 20, of appropriate cross section, are arranged in a helical winding inside the envelope 10 where they are immersed in the sodium 12, so as to transfer to a volatile secondary fluid, such as water, circulating in the tubes 20, the greatest possible thermal power compatible with the good behavior of the tubes. Due to the volatile nature of the secondary fluid circulating in the tubes 20, the length and the section of the tubes 20 are chosen so that the fluid entering through the lower end of the tubes in the liquid state leaves at their upper end at l state of superheated steam under the effect of the heat given off by liquid sodium 12. In the steam generator shown in FIG.
  • the lower and upper ends of the tubes 20 are connected respectively to four inlet water boxes 22 and to four outlet steam boxes 24, only two of each of these boxes being shown in FIG. 1.
  • the inlet 22 and outlet 24 boxes are substantially identical and each have a cylindrical wall with a vertical axis, produced in one piece with an upper end wall into which the corresponding ends of the tubes 20 open, and their end lower is closed by a removable cover 23, 25 allowing access to the orifices of the facing tubes, in particular in order to carry out the inspection of the latter.
  • at least one inlet pipe 26 and at least one outlet pipe 28 open into the tubular wall of each of the boxes 22 and 24, respectively.
  • the pipes 26 and 28 make it possible to connect each of the boxes to water and steam collectors, respectively, each rectilinear collector receiving the output of two boxes.
  • the collectors are themselves connected to the electricity production installation.
  • the plates constituting the walls of the boxes must be relatively thick to resist the pressure of the secondary fluid, and the seal between the removable cover and the box is ensured by an autoclave seal.
  • a relatively large diameter up to for example 420 mm, so that leaks can occur during operation.
  • the invention proposes with reference to FIG. 2 a steam generator substantially of the same type as that shown in FIG. 1 and comprising in particular a substantially cylindrical sealed envelope with a vertical axis 110, inlet 114 and outlet 116 orifices for the primary fluid 112 formed respectively at the upper part and at the base of the envelope 110, the primary fluid 112 being under an argon atmosphere 118, while the secondary fluid circulates in tubes 120 arranged for example in a helical winding inside the envelope 110, so that the secondary fluid circulates between the lower end 130 and the upper end 132 of these tubes 120.
  • the lower 130 and upper 132 ends of the tubes 120 open onto annular parts of the cylindrical wall of the casing 110 and extend outside of the latter by parts 134 and 136 the ends of which open respectively into a tubular inlet manifold 138 and into a tubular outlet manifold 140 surrounding at least partially the envelope 110 of the steam generator.
  • the collectors 138 and 140 are arranged below the ends 130 and 132 of the tubes 120, so that the parts 134 and 136 arranged outside the casing 110 open into the upper part of the collectors 138 and 140.
  • the inlet manifold 138 is supplied with secondary liquid such as water by at least one inlet pipe 142, for example by means of a pump (not shown), and the outlet manifold 140 delivers steam of water by at least one outlet pipe 144 to one or more known devices (not shown), making it possible to transform the energy stored by water vapor into energy which can be used industrially, and in particular electrical energy.
  • the tubes 120 constitute a part of a closed circuit generally constituting the supply circuit of the installation for producing electricity in a nuclear reactor cooled by liquid metal and in which the volatile secondary liquid such as liquid circulates. 'water.
  • the tubular shape of the collectors 138 and 140 makes it possible to substantially reduce the thickness of the walls which constitute them, due to the reduction of the stresses generated in the wall by a given internal pressure, compared to the box-shaped collectors formed by a plate plane into which open the tubes and a cover.
  • the internal diameter of each of the tubular collectors can be around 400 mm.
  • access to the ends 130 and 132 of each of the tubes 120 is effected by access devices 146 comprising orifices formed in each of the parts 134, 136 and normally closed by removable plugs 148. It is thus possible to '' have individual access to the two ends of each of the tubes 120, without the need to provide the collectors 138 and 140 with a large cover whose sealing may prove to be defective during operation of the reactor.
  • the casing 110 and the collectors 138 and 140 are generally disposed inside a thermal insulation (not shown), and the access devices 146 then protrude outside of this thermal insulation.
  • the manifolds 138 and 140 as well as the external parts 134 and 136 of the tubes 120 are symmetrical, so that only the inlet manifold 138 and one of the parts will be described. corresponding external 134 of the tubes 120 with reference to FIG. 3, before describing an example of the spatial distribution of these parts of tubes with reference to FIGS. 4 and 5.
  • Each of the parts 134 has a rectilinear portion 150 which extends in a direction substantially normal to the envelope 110 of the steam generator and a substantially vertical portion 152 forming a T with the rectilinear portion 150 for connecting the latter to the manifold 138.
  • the straight portion 150 of the external part 134 of the tube 120 ends with the access device 146, normally closed by the plug 148 as illustrated in particular in FIG. 6.
  • the vertical portion 152 of the outer portion 134 is connected to the straight portion 150 near the access device 146, so that different control, measurement, etc. devices can be introduced into the outer portion 134 at the level of the connection between the portions 150 and 152 of each of the external parts of the tubes, as will be seen below.
  • the internal section of the tubes 120 is preferably constant, even at the level of the external parts 134 and 136.
  • each of the tubes comprises, at the end of its rectilinear portion 150, surrounding the access device 146, a threaded part 154 on which is screwed a nut 156 by means of which the corresponding plug 148, or any other control device or measurement, is biased against the annular end of the straight portion 150 of the tube, so that an annular seal 158 carried by the plug 148 engages this end in a sealed manner.
  • this portion 150 is provided with an anti-torsion device 160 (see FIG.
  • the tube 3 comprising a tube, one end of which is fixed to the casing 110 of the generator by any suitable means such as, for example, by a weld 162, and the other end of which has two diametrically opposite notches 164 which extend in a longitudinal direction relative to the tube 160 and in which penetrate fingers 166 extending radially outward from the end of the straight portion 150 in which is formed the access orifice 146.
  • the number of notches 164 and of fingers 166 can be different from two and the fingers 166 can also be attached to the straight portion 150 of the pipe.
  • the anti-torsion tube 160 also has in its lower part a longitudinal slot 168 which the vertical portion 152 of the tube 120 crosses.
  • the rectilinear portion 150 of each of the external parts 134 or 136 of the tubes 120 passes through the envelope 110 of the steam generator with a certain clearance and it is fixed to the latter by a thermal sleeve 170 placed inside the envelope and fixed thereto by any suitable means such as, for example, by welding.
  • This structure makes it possible to compensate for the deformations resulting from the expansion of the tubes and of the envelope of the steam generator.
  • each of the vertical portions 152 has the shape of a lyre as shown in dashed lines in FIG. 3 and as shown more precisely in FIG. 4.
  • each of the branch portions 152 is fixed to the wall of the corresponding collector by any suitable means such as, for example, by welding, and communicates with the interior of this collector by a radial opening 172 formed in the wall of this last.
  • the distribution in space of the external parts 134 of the tubes 120 requires special care due to the large number of tubes opening out of the casing 110 of the exchanger and the particular shape of the external parts 134 imposed by the invention.
  • the tubes 120 pass through the envelope 110 in a number of superimposed layers (five in the figures) and form rows regularly distributed over the circumference of the envelope, each row being constituted by a tube of each layer and the tubes of each row being aligned along a generatrix of the envelope.
  • the rectilinear portions 150 of each of the tubes protrude radially outside the casing 110 of the exchanger, so that they are distributed in five superimposed layers, defining rows of five rectilinear portions regularly distributed at the periphery of the envelope.
  • the portions 152 open laterally on the portions 150, as shown in FIG. 5, so as to be able to descend vertically between the rows formed by the tubes, the mouth of the portion 152 in the portion 150 being all the more distant from the envelope 110 as the portion 150 is in a sheet closer to the manifold 138 (see fig. 4).
  • the portions 152 corresponding to the same row of tubes, open out alternately on one side and on the other of the portions 150 (see FIG. 5), so that the portions 152 corresponding to two neighboring rows are staggered in their vertical parts arranged between these rows.
  • the portions 152 can all open out on the same side of the row of portions 150 which corresponds to them, and the vertical parts of the portions 152 disposed between two adjacent rows then all correspond to the same row of tubes.
  • the portions 152 corresponding to the same row of tubes are brought back in the radial plane passing through the rectilinear portions 150 of this row of tubes, to form there nested expansion lyres (FIG. 4).
  • the portions 152 of each row of tubes are then connected to the manifold 138, at equal distance from each other, over a sector defined at the top of the manifold, in the same radial plane as the portions 150 which correspond to them.
  • the access from each of the openings is particularly easy as illustrated in particular in figs. 3 and 4. It is thus possible to use the access orifice formed in each of the rectilinear portions 150 to carry out, when stationary, an inspection of the tube by eddy currents or a tightness control. Furthermore, it is possible to install, through this orifice, devices for adjusting, measuring or controlling the operation of the generator, as explained below, in the description of FIGS. 7 and 8.
  • fig. 3 illustrates the replacement of one of the plugs 148 by a device for checking the tightness of the corresponding tube 120, designated by the general reference 174.
  • This device is put in place after the steam generator has cooled and the secondary circuit has been drained. It essentially comprises a tubular end-piece 176, extending beyond the T-shaped connection of the portion 152, for sealing the latter in a sealed manner by means of two annular seals 178 arranged on either side of the mouth of the vertical portion.
  • the tubular endpiece 176 comprises a collar 180, tightened by means of the nut 156 against the free end of the straight portion 150 of the tube, in which is housed a porous member such as a sponge 182 filled, for example with water soapy.
  • the device 174 thus makes it possible to observe the bubbles which form in the soapy water impregnating the sponge 182 at the outlet of the tubular nozzle. 176 in the event of a leak in the wall of the corresponding tube 120.
  • This leak detection device is only described by way of nonlimiting example and can be replaced by any other known device.
  • the device described can be used differently by impregnating the sponge 182 with a reagent sensitive to a determined gas which is injected into the argon at inside the envelope 110 of the steam generator, this gas can for example be ammonia.
  • the coloring of the reagent is then observed through a transparent plate 184 partially closing off the end of the device 174.
  • Another means of checking the tightness of the tubes using the inspection orifices 146 formed at the ends of each of the tubes 120 consists to inject helium into the envelope 110 of the generator, to seal off one of the ends of the tube by means of the plug 148 and to connect a helium detector of a known type at the other end.
  • thermowell support 186 capable of receiving a temperature measurement device such as a thermocouple connected to a measurement device suitable and the sensitive part of which is preferably arranged at the connection of the vertical portion 152 on the rectilinear portion 150.
  • the thermocouple capable of being received in the thermowell support 186 carried by the plug 148 may allow, in particular, to measure the temperature of the superheated steam leaving a certain number of tubes 120 suitably chosen.
  • FIG. 8 there is shown in FIG. 8 the rectilinear portion 150 of the external portion 134 of a tube 120 whose end opens into the inlet manifold 138, the plug 148 closing the access orifice 146 formed in the portion 150 carrying a diaphragm 188 which allows to stabilize the flow of water circulating in the tubes 120 of the steam generator.
  • the diaphragm 188 is formed at the end of a tubular organ 190 carried by the plug 148 and extending beyond the junction between the vertical portion 1.52 and the straight portion 150 of the portion 134.
  • the tubular member 190 is perforated laterally by means of holes 192 formed at the vertical portion 152, and an annular seal 184 is disposed between the tubular member 190 and the straight portion 150 of the tube between the branch portion 152 and the casing 110 of the generator vapor, so that the water from the inlet manifold 138 and entering the straight portion 150 through the portion 152 must pass through the holes 192 and the diaphragm 188 before entering the interior of the steam generator.
  • the control and possible replacement of the diaphragms 188 can thus be carried out in a particularly simple manner.
  • the diaphragm 188 can be replaced by any device creating a similar pressure drop.
  • the measurement and control devices which have just been described by way of example are not limiting of the possibilities of access to the ends of the tubes of the steam generator resulting from the present invention.
  • the dismantling of each of the plugs 148 may allow after cooling and emptying of the generator the introduction of any known measurement or control devices such as, for example, an eddy current or ultrasonic probe allowing the inspection of each of the tubes.
  • the invention is not limited to a steam generator and concerns all the heat exchangers geurs in which the heat conveyed by a primary fluid is used to heat a secondary fluid.

Description

L'invention concerne un échangeur conçu notamment pour assurer un transfert de chaleur entre deux circuits d'une centrale nucléaire.The invention relates to an exchanger designed in particular to ensure heat transfer between two circuits of a nuclear power plant.

L'invention concerne en particulier un échangeur tel qu'un générateur de vapeur comprenant une enveloppe dans laquelle la chaleur véhiculée par un fluide primaire est transférée à un fluide secondaire de façon à échauffer et, éventuellement, à vaporiser ce dernier, le fluide secondaire circulant dans des tubes dont les extrémités opposées débouchent dans des collecteurs d'entrée et de sortie disposés à l'extérieur de l'enveloppe du générateur. Les générateurs de vapeur de ce type sont utilisés notamment, bien que non exclusivement, dans les circuits des réacteurs nucléaires à refroidissement par métal liquide, pour assurer un transfert de chaleur entre un circuit de refroidissement dans lequel circule un métal liquide, tel que du sodium, et un circuit alimentant une installation de production d'électricité dans lequel circule un liquide tel que de l'eau.The invention relates in particular to an exchanger such as a steam generator comprising an envelope in which the heat conveyed by a primary fluid is transferred to a secondary fluid so as to heat and, optionally, to vaporize the latter, the circulating secondary fluid in tubes whose opposite ends open into inlet and outlet manifolds arranged outside the generator casing. Steam generators of this type are used in particular, although not exclusively, in the circuits of nuclear reactors cooled by liquid metal, to ensure heat transfer between a cooling circuit in which a liquid metal, such as sodium, circulates. , and a circuit supplying an electricity production installation in which a liquid such as water circulates.

Dans les générateurs de vapeur de ce type, la longueur des tubes dans lesquels circule le fluide secondaire, généralement constitué par de l'eau, est adaptée à la qualité de vapeur à produire et souvent de l'ordre d'une centaine de mètres, et le nombre de ces tubes est relativement important, de façon à permettre un échange de chaleur aussi complet que possible entre le sodium liquide qui constitue généralement le fluide primaire et l'eau, ou la vapeur circulant dans les tubes, ces derniers baignant dans le sodium liquide. Pour des raisons de sécurité évidentes, il est impératif de pouvoir vérifier l'étanchéité des tubes. Il est également nécessaire de pouvoir procéder à certaines mesures et, notamment, à la mesure de la température de la vapeur à la sortie des tubes, ainsi qu'à certains contrôles lors des périodes d'arrêt du générateur tels que l'inspection individuelle de chacun des tubes, par exemple à l'aide d'une sonde à courants de Foucault ou à ultrasons.In steam generators of this type, the length of the tubes in which the secondary fluid circulates, generally consisting of water, is adapted to the quality of steam to be produced and often of the order of a hundred meters, and the number of these tubes is relatively large, so as to allow a heat exchange as complete as possible between the liquid sodium which generally constitutes the primary fluid and the water, or the vapor circulating in the tubes, the latter bathing in the liquid sodium. For obvious safety reasons, it is imperative to be able to check the tightness of the tubes. It is also necessary to be able to carry out certain measurements and, in particular, to measure the temperature of the vapor at the outlet of the tubes, as well as certain controls during periods of shutdown of the generator such as the individual inspection of each of the tubes, for example using an eddy current or ultrasonic probe.

On connaît des générateurs de vapeur dans lesquels les tubes débouchent à chacune de leurs extrémités dans une boîte à eau et une boîte à vapeur sensiblement cylindriques, les boîtes d'entrée et de sortie étant par exemple chacune au nombre de quatre, alors que le générateur comprend environ 360 tubes, de telle sorte qu'environ 90 tubes débouchent dans chacune des boîtes. Des collecteurs rassemblent les sorties des boîtes à eau et à vapeur. Afin de permettre les contrôles et les mesures mentionnées précédemment, les tubes débouchent dans chacune des boîtes à l'une de ses extrémités, tandis que l'autre extrémité de la boîte est fermée par un couvercle amovible dont le démontage permet d'avoir accès à l'orifice de chacun des tubes débouchant dans cette boîte. En raison du nombre de tubes débouchant dans chacune des boîtes, les dimensions de ces dernières sont relativement importantes, de telle sorte qu'elles doivent comporter des plaques tubulaires et des parois épaisses, et que le diamètre du couvercle est relativement important. Il en résulte que l'étanchéité entre chaque boîte et son couvercle, qui est réalisée habituellement au moyen d'un joint autoclave, dont le diamètre peut atteindre environ 420 mm, risque de présenter des défauts lors du fonctionnement. Par ailleurs, les dimensions de la boîte, qui présente une longueur relativement importante par rapport à son diamètre, rendent assez difficile le repérage des tubes et l'accès à un orifice bien déterminé. Enfin, l'échangeur et les collecteurs sont généralement disposés à l'intérieur d'un calorifuge qu'il est nécessaire de démonter avant d'avoir accès aux tubes.Steam generators are known in which the tubes open at each of their ends in a water box and a substantially cylindrical steam box, the inlet and outlet boxes being for example each four in number, while the generator contains approximately 360 tubes, so that approximately 90 tubes open into each of the boxes. Collectors collect the outlets of the water and steam boxes. In order to allow the checks and measurements mentioned above, the tubes open into each of the boxes at one of its ends, while the other end of the box is closed by a removable cover, the dismantling of which allows access to the orifice of each of the tubes opening into this box. Because of the number of tubes opening into each of the boxes, the dimensions of the latter are relatively large, so that they must have tubular plates and thick walls, and the diameter of the cover is relatively large. As a result, the seal between each box and its cover, which is usually achieved by means of an autoclave seal, the diameter of which can reach approximately 420 mm, risks presenting defects during operation. Furthermore, the dimensions of the box, which has a relatively large length compared to its diameter, make it quite difficult to locate the tubes and access to a well-defined orifice. Finally, the exchanger and the collectors are generally arranged inside an insulating material which it is necessary to dismantle before having access to the tubes.

On connaît aussi du brevet FR-A N° 2379881 un échangeur de chaleur vertical dans lequel les extrémités des tubes débouchent dans des collecteurs tubulaires disposés à l'extérieur de l'enveloppe de l'échangeur et entourant celle-ci. Dans cet échangeur, un orifice d'accès obturé par un bouchon est formé dans le collecteur d'entrée, en face de chacun des tubes. Par rapport à la structure précédente, cette structure permet de diminuer les dimensions des joints d'étanchéité au niveau des collecteurs. En revanche, elle en augmente le nombre, de sorte que l'étanchéité des collecteurs reste un problème. De plus, la réalisation des orifices d'accès dans le collecteur nécessite le démontage du calorifuge, comme dans la structure précédente. Cette caractéristique a aussi pour conséquence de conduire à une disposition particulière des tubes conduisant, d'une part, à perturber l'écoulement du fluide de refroidissement à l'intérieur du collecteur et, d'autre part, à limiter le nombre de tubes équipés d'un dispositif d'accès.Also known from patent FR-A No. 2379881 is a vertical heat exchanger in which the ends of the tubes open into tubular collectors arranged outside the envelope of the exchanger and surrounding the latter. In this exchanger, an access orifice closed by a plug is formed in the inlet manifold, opposite each of the tubes. Compared to the previous structure, this structure makes it possible to reduce the dimensions of the seals at the level of the collectors. However, it increases the number, so that the tightness of the collectors remains a problem. In addition, the realization of the access holes in the collector requires the disassembly of the insulation, as in the previous structure. This characteristic also has the consequence of leading to a particular arrangement of the tubes leading, on the one hand, to disturb the flow of the coolant inside the collector and, on the other hand, to limit the number of tubes fitted an access device.

L'invention a pour objet un échangeur permettant de supprimer les inconvénients, mentionnés précédemment, des échangeurs connus, tout en facilitant l'accès aux orifices de chacun des tubes, ainsi que leur étanchéité, d'effectuer les mesures nécessaires ou de vérifier l'état d'un dispositif de stabilisation de débit (diaphragme).The subject of the invention is an exchanger making it possible to eliminate the drawbacks, mentioned above, of known exchangers, while facilitating access to the orifices of each of the tubes, as well as their sealing, to carry out the necessary measurements or to verify the condition of a flow stabilization device (diaphragm).

Dans ce but, un échangeur comprenant une enveloppe dans laquelle la chaleur véhiculée par un fluide primaire est transférée à un fluide secondaire de façon à échauffer ce dernier, le fluide secondaire circulant dans des tubes dont les extrémités opposées débouchent dans des collecteurs tubulaires d'entrée et de sortie disposés à l'extérieur de l'enveloppe de l'échangeur et entourant celle-ci au moins en partie, l'accès aux extrémités s'effectuant par des dispositifs d'accès obturés par un bouchon amovible étant prévu pour chacun des tubes, chacun des dispsitifs d'accès étant disposé dans une partie du tube située entre l'enveloppe de l'échangeur et le collecteur correspondant.For this purpose, an exchanger comprising a casing in which the heat conveyed by a primary fluid is transferred to a secondary fluid so as to heat the latter, the secondary fluid circulating in tubes whose opposite ends open into tubular inlet manifolds and outlet disposed outside of the shell of the exchanger and surrounding it at least in part, access to the ends being effected by access devices closed by a removable plug being provided for each of the tubes, each of the access devices being arranged in a part of the tube located between the shell of the exchanger and the corresponding collector.

L'adoption de collecteurs de forme tubulaire, connue par ailleurs, permet de réduire sensiblement l'épaisseur des parois par rapport aux boîtes de forme cylindrique en raison de la diminution des contraintes qui en résulte au niveau des parois pour une pression interne donnée. De plus, la réalisation à chaque extrémité des tubes, entre le collecteur et l'enveloppe de l'échangeur, d'un dispositif d'accès obturé par un bouchon amovible permet d'éviter les problèmes d'étanchéité liés aux grandes dimensions de l'orifice à obturer et de faciliter l'accès individuel à chacun des tubes, notamment en disposant les dispositifs d'accès en dehors du calorifuge, lorsque l'enveloppe de l'échangeur et les collecteurs sont dans un calorifuge.The adoption of tubular collectors, which is also known, makes it possible to significantly reduce the thickness of the walls compared to cylindrical boxes due to the reduction in resulting stresses at the walls for a given internal pressure. In addition, the realization at each end of the tubes, between the collector and the shell of the exchanger, of an access device closed by a removable plug avoids the sealing problems associated with the large dimensions of the orifice to be closed and to facilitate individual access to each of the tubes, in particular by arranging the access devices outside the insulation, when the shell of the exchanger and the collectors are in an insulation.

Conformément à un mode de réalisation préférentiel de l'invention, chacune desdites parties des tubes présente une première portion rectiligne, se terminant par le dispositif d'accès, et une deuxième portion, formant un T avec la portion rectiligne et reliant cette dernière au collecteur correspondant.According to a preferred embodiment of the invention, each of said parts of the tubes has a first straight portion, ending with the access device, and a second portion, forming a T with the straight portion and connecting the latter to the manifold. corresponding.

De préférence, la portion rectiligne de chacune desdites parties des tubes s'étend alors selon une direction sensiblement normale à l'enveloppe de l'échangeur.Preferably, the rectilinear portion of each of said parts of the tubes then extends in a direction substantially normal to the shell of the exchanger.

De même, la deuxième portion de chacune desdites parties des tubes est reliée de préférence à la portion rectiligne à proximité du dispositif d'accès correspondant. Le bouchon obturant le dispositif d'accès disposé dans la partie de chacun des tubes située entre l'enveloppe de l'échangeur et le collecteur d'entrée peut alors porter un organe tubulaire qui s'étend dans la portion rectiligne de ladite partie des tubes au-delà du raccordement de la deuxième portion de ladite partie des tubes, l'organe tubulaire étant ajouré latéralement au niveau de la deuxième portion et supportant un diaphragme ou plus généralement un dispositif créant une perte de charge analogue au-delà de cette dernière.Similarly, the second portion of each of said parts of the tubes is preferably connected to the straight portion near the corresponding access device. The plug closing the access device arranged in the part of each of the tubes located between the shell of the exchanger and the inlet manifold can then carry a tubular member which extends in the straight portion of said part of the tubes. beyond the connection of the second portion of said part of the tubes, the tubular member being perforated laterally at the level of the second portion and supporting a diaphragm or more generally a device creating a similar pressure drop beyond the latter.

Conformément à une caractéristique secondaire de l'invention, la deuxième portion de chacune desdites parties des tubes forme une lyre de dilatation. Cette caractéristique permet de limiter avantageusement la réaction exercée par chacun des tubes sur le manchon thermique qui relie celui- ci à l'enveloppe de l'échangeur, lors des variations de température du fluide circulant dans les tubes.In accordance with a secondary characteristic of the invention, the second portion of each of said parts of the tubes forms a dilatation lyre. This characteristic makes it possible to advantageously limit the reaction exerted by each of the tubes on the thermal sleeve which connects the latter to the shell of the exchanger, during variations in temperature of the fluid circulating in the tubes.

Conformément à une autre caractéristique secondaire de l'invention, la portion rectiligne de chacune desdites parties des tubes est entourée par un dispositif antitorsion dont une extrémité est fixée à l'enveloppe de l'échangeur et dont l'autre extrémité présente par exemple au moins une encoche longitudinale dans laquelle pénètre un doigt solidaire de la portion rectiligne au voisinage du dispositif d'accès, le dispositif antitorsion comprenant de plus une fente longitudinale que traverse la deuxième portion de la partie de tube correspondante. Cette caractéristique permet de s'opposer à la torsion de la portion rectiligne, notamment lors de la mise en place, ou du démontage, du bouchon obturant le dispositif d'accès.According to another secondary characteristic of the invention, the rectilinear portion of each of said parts of the tubes is surrounded by an anti-torsion device, one end of which is fixed to the shell of the exchanger and the other end of which has, for example, at least a longitudinal notch into which a finger integral with the rectilinear portion penetrates in the vicinity of the access device, the anti-torsion device further comprising a longitudinal slot through which the second portion of the corresponding tube part passes. This characteristic makes it possible to oppose the torsion of the rectilinear portion, in particular during the installation, or the disassembly, of the plug closing the access device.

Conformément à un mode de réalisation particulier de l'invention, chacune desdites parties des tubes comprend une portion filetée entourant le dispositif d'accès, sur laquelle est vissé un écrou au moyen duquel le bouchon correspondant est sollicité normalement de façon étanche contre le dispositif d'accès.In accordance with a particular embodiment of the invention, each of said parts of the tubes comprises a threaded portion surrounding the access device, onto which is screwed a nut by means of which the corresponding plug is normally pressed in a sealed manner against the device. 'access.

Selon encore une autre caractéristique de l'invention, au moins l'un des bouchons obturant les dispositifs d'accès porte un dispositif de mesure de température et tous peuvent être remplacés par un dispositif de contrôle d'étanchéité.According to yet another characteristic of the invention, at least one of the plugs blocking the access devices carries a temperature measuring device and all of them can be replaced by a sealing control device.

On décrira maintenant, à titre d'exemple non limitatif, un mode de réalisation particulier de l'invention en se référant aux dessins annexés dans lesquels:

  • la fig. 1 est une vue en coupe schématique représentant un générateur de vapeur de l'art antérieur,
  • la fig. 2 est une vue en coupe schématique semblable à la fig. 1 représentant un générateur de vapeur réalisé conformément aux enseignements de la présente invention,
  • la fig. 3 est une vue agrandie, en coupe partielle, d'un détail du générateur de vapeur, représenté sur la fig. 2, montrant une extrémité de l'un des tubes dans lequel circule le fluide secondaire et, notamment, la partie située à l'extérieur de l'enveloppe du générateur et débouchant dans un collecteur torique, illustrant en particulier la mise en place d'un dispositif de détection de fuites dans le dispositif d'accès formé dans le tube,
  • la fig. 4 est une vue comparable à la fig. 3 montrant la dispôsition des parties des tubes situées entre l'enveloppe du générateur et l'un des collecteurs,
  • la fig. 5 est une vue selon la flèche 5 de la fig. 4,
  • la fig. 6 représente la portion rectiligne formée à une extrémité de l'un des tubes du générateur, représenté sur la fig. 2, à l'extérieur de l'enveloppe du générateur et illustre, en particulier, l'obturation du dispositif d'accès par un bouchon amovible,
  • la fig. 7 est une vue semblable à la fig. 6, dans laquelle le bouchon obturant le dispositif d'accès porte un dispositif de mesure de température, et
  • la fig. 8 est une vue semblable aux fig. 6 et 7 dans laquelle le bouchon amovible obturant le dispositif d'accès supporte un diaphragme destiné à stabiliser le débit du liquide secondaire pénétrant dans le tube correspondant du générateur. Ce dernier cas correspond au collecteur d'entrée du liquide secondaire dans l'appareil.
A particular embodiment of the invention will now be described, by way of nonlimiting example, with reference to the appended drawings in which:
  • fig. 1 is a schematic sectional view showing a steam generator of the prior art,
  • fig. 2 is a schematic sectional view similar to FIG. 1 representing a steam generator produced in accordance with the teachings of the present invention,
  • fig. 3 is an enlarged view, in partial section, of a detail of the steam generator, shown in FIG. 2, showing one end of one of the tubes in which the secondary fluid circulates and, in particular, the part situated outside the generator casing and opening into a toroidal manifold, illustrating in particular the installation of a device for detecting leaks in the access device formed in the tube,
  • fig. 4 is a view comparable to FIG. 3 showing the arrangement of the parts of the tubes situated between the envelope of the generator and one of the collectors,
  • fig. 5 is a view along arrow 5 in FIG. 4,
  • fig. 6 shows the rectilinear portion formed at one end of one of the tubes of the generator, shown in FIG. 2, outside the generator casing and illustrates, in particular, closing the access device with a removable plug,
  • fig. 7 is a view similar to FIG. 6, in which the plug closing the access device carries a temperature measuring device, and
  • fig. 8 is a view similar to FIGS. 6 and 7 in which the removable plug closing the access device supports a diaphragm intended to stabilize the flow rate of the secondary liquid entering the corresponding tube of the generator. The latter case corresponds to the secondary liquid inlet manifold in the device.

Le générateur de vapeur représenté schématiquement sur la fig. 1 est un générateur connu, prévu pour être disposé entre un circuit de refroidissement d'un réacteur nucléaire à refroidissement par métal liquide et un circuit alimentant une installation de production d'électricité. Un générateur de vapeur de ce type comprend une enveloppe 10, de forme générale cylindrique, disposée verticalement et à l'intérieur de laquelle circule un fluide primaire 12, constitué notamment par un métal liquide tel que du sodium, qui pénètre à l'extrémité supérieure de l'enveloppe 10 par des orifices d'entrée 14 et qui ressort du générateur de vapeur par un orifice de sortie 16 formé à la base de l'enveloppe 10.The steam generator shown diagrammatically in FIG. 1 is a known generator, intended to be disposed between a cooling circuit of a nuclear reactor cooled by liquid metal and a circuit supplying an installation for producing electricity. A steam generator of this type comprises a casing 10, of generally cylindrical shape, arranged vertically and inside which circulates a primary fluid 12, constituted in particular by a liquid metal such as sodium, which penetrates at the upper end of the casing 10 by inlet orifices 14 and which emerges from the steam generator by an outlet orifice 16 formed at the base of the casing 10.

Le plus souvent, le sodium 12 circule dans un circuit d'un réacteur nucléaire et véhicule la chaleur provenant des réactions se produisant dans le coeur de ce réacteur.Most often, sodium 12 circulates in a circuit of a nuclear reactor and carries the heat coming from the reactions occurring in the core of this reactor.

L'enveloppe 10 est étanche et le sodium 12 est placé sous atmosphère d'argon 18. Un certain nombre de tubes 20, de section appropriée, sont disposés selon un enroulement hélicoïdal à l'intérieur de l'enveloppe 10 où ils baignent dans le sodium 12, de façon à transférer à un fluide secondaire volatil, tel que de l'eau, circulant dans les tubes 20, la plus grande puissance thermique possible compatible avec la bonne tenue des tubes. En raison du caractère volatil du fluide secondaire circulant dans les tubes 20, la longueur et la section des tubes 20 sont choisies de telle sorte que le fluide pénétrant par l'extrémité inférieure des tubes à l'état liquide ressort à leur extrémité supérieure à l'état de vapeur surchauffée sous l'effet de la chaleur cédée par le sodium liquide 12. Dans le générateur de vapeur représenté sur la fig. 1, les extrémités inférieures et supérieures des tubes 20 sont reliées respectivement à quatre boîtes à eau d'entrée 22 et à quatre boîtes à vapeur de sortie 24, deux seulement de chacune de ces boîtes étant représentées sur la fig. 1. Les boîtes d'entrée 22 et de sortie 24 sont sensiblement identiques et présentent chacune une paroi cylindrique d'axe vertical, réalisée d'un seul tenant avec une paroi terminale supérieure dans laquelle débouchent les extrémités correspondantes des tubes 20, et leur extrémité inférieure est fermée par un couvercle démontable 23, 25 permettant l'accès aux orifices des tubes en vis-à-vis, notamment afin de procéder à l'inspection de ces derniers. En outre, au moins une canalisation d'entrée 26 et au moins une canalisation de sortie 28 débouchent dans la paroi tubulaire de chacune des boîtes 22 et 24, respectivement. Les canalisations 26 et 28 permettent de relier chacune des boîtes à des collecteurs d'eau et de vapeur, respectivement, chaque collecteur rectiligne recevant la sortie de deux boîtes. Les collecteurs sont eux-mêmes reliés à l'installation de production d'électricité.The envelope 10 is sealed and the sodium 12 is placed under an argon atmosphere 18. A number of tubes 20, of appropriate cross section, are arranged in a helical winding inside the envelope 10 where they are immersed in the sodium 12, so as to transfer to a volatile secondary fluid, such as water, circulating in the tubes 20, the greatest possible thermal power compatible with the good behavior of the tubes. Due to the volatile nature of the secondary fluid circulating in the tubes 20, the length and the section of the tubes 20 are chosen so that the fluid entering through the lower end of the tubes in the liquid state leaves at their upper end at l state of superheated steam under the effect of the heat given off by liquid sodium 12. In the steam generator shown in FIG. 1, the lower and upper ends of the tubes 20 are connected respectively to four inlet water boxes 22 and to four outlet steam boxes 24, only two of each of these boxes being shown in FIG. 1. The inlet 22 and outlet 24 boxes are substantially identical and each have a cylindrical wall with a vertical axis, produced in one piece with an upper end wall into which the corresponding ends of the tubes 20 open, and their end lower is closed by a removable cover 23, 25 allowing access to the orifices of the facing tubes, in particular in order to carry out the inspection of the latter. In addition, at least one inlet pipe 26 and at least one outlet pipe 28 open into the tubular wall of each of the boxes 22 and 24, respectively. The pipes 26 and 28 make it possible to connect each of the boxes to water and steam collectors, respectively, each rectilinear collector receiving the output of two boxes. The collectors are themselves connected to the electricity production installation.

Dans le générateur de vapeur connu qui vient d'être décrit, les plaques constituant les parois des boîtes doivent être relativement épaisses pour résister à la pression du fluide secondaire, et l'étanchéité entre le couvercle démontable et la boîte est assurée par un joint autoclave d'un diamètre relativement important, pouvant atteindre par exemple 420 mm, de sorte que des défauts d'étanchéité peuvent se produire en cours de fonctionnement.In the known steam generator which has just been described, the plates constituting the walls of the boxes must be relatively thick to resist the pressure of the secondary fluid, and the seal between the removable cover and the box is ensured by an autoclave seal. a relatively large diameter, up to for example 420 mm, so that leaks can occur during operation.

Afin de remédier à ces inconvénients, l'invention propose en se référant à la fig. 2 un générateur de vapeur sensiblement du même type que celui représenté sur la fig. 1 et comprenant notamment une enveloppe étanche sensiblement cylindrique et d'axe vertical 110, des orifices d'entrée 114 et de sortie 116 du fluide primaire 112 formés respectivement à la partie supérieure et à la base de l'enveloppe 110, le fluide primaire 112 étant sous atmosphère d'argon 118, tandis que le fluide secondaire circule dans des tubes 120 disposés par exemple selon un enroulement hélicoïdal à l'intérieur de l'enveloppe 110, de telle sorte que le fluide secondaire circule entre l'extrémité inférieure 130 et l'extrémité supérieure 132 de ces tubes 120. Les extrémités inférieure 130 et supérieure 132 des tubes 120 débouchent sur des parties annulaires de la paroi cylindrique de l'enveloppe 110 et se prolongent à l'extérieur de cette dernière par des parties 134 et 136 dont les extrémités débouchent respectivement dans un collecteur tubulaire d'entrée 138 et dans un collecteur tubulaire de sortie 140 entourant au moins en partie l'enveloppe 110 du générateur de vapeur. Comme le montre la fig. 2, les collecteurs 138 et 140 sont disposés en dessous des extrémités 130 et 132 des tubes 120, de telle sorte que les parties 134 et 136 disposées à l'extérieur de l'enveloppe 110 débouchent dans la partie supérieure des collecteurs 138 et 140. Le collecteur d'entrée 138 est alimenté en liquide secondaire tel que de l'eau par au moins une canalisation d'entrée 142, par exemple au moyen d'une pompe (non représentée), et le collecteur de sortie 140 délivre de la vapeur d'eau par au moins une canalisation de sortie 144 à un ou plusieurs dispositifs connus (non représentés), permettant de transformer l'énergie emmagasinée par la vapeur d'eau en énergie utilisable industriellement, et notamment en énergie électrique. Ainsi, les tubes 120 constituent une partie d'un circuit fermé constituant généralement le circuit d'alimentation de l'installation de production de l'électricité dans un réacteur nucléaire refroidi par métal liquide et dans lequel circule le liquide secondaire volatil tel que de l'eau.In order to remedy these drawbacks, the invention proposes with reference to FIG. 2 a steam generator substantially of the same type as that shown in FIG. 1 and comprising in particular a substantially cylindrical sealed envelope with a vertical axis 110, inlet 114 and outlet 116 orifices for the primary fluid 112 formed respectively at the upper part and at the base of the envelope 110, the primary fluid 112 being under an argon atmosphere 118, while the secondary fluid circulates in tubes 120 arranged for example in a helical winding inside the envelope 110, so that the secondary fluid circulates between the lower end 130 and the upper end 132 of these tubes 120. The lower 130 and upper 132 ends of the tubes 120 open onto annular parts of the cylindrical wall of the casing 110 and extend outside of the latter by parts 134 and 136 the ends of which open respectively into a tubular inlet manifold 138 and into a tubular outlet manifold 140 surrounding at least partially the envelope 110 of the steam generator. As shown in fig. 2, the collectors 138 and 140 are arranged below the ends 130 and 132 of the tubes 120, so that the parts 134 and 136 arranged outside the casing 110 open into the upper part of the collectors 138 and 140. The inlet manifold 138 is supplied with secondary liquid such as water by at least one inlet pipe 142, for example by means of a pump (not shown), and the outlet manifold 140 delivers steam of water by at least one outlet pipe 144 to one or more known devices (not shown), making it possible to transform the energy stored by water vapor into energy which can be used industrially, and in particular electrical energy. Thus, the tubes 120 constitute a part of a closed circuit generally constituting the supply circuit of the installation for producing electricity in a nuclear reactor cooled by liquid metal and in which the volatile secondary liquid such as liquid circulates. 'water.

La forme tubulaire des collecteurs 138 et 140 permet de réduire sensiblement l'épaisseur des parois qui les constituent, en raison de la diminution des contraintes engendrées dans la paroi par une pression interne donnée, par rapport aux collecteurs en forme de boîte formés par une plaque plane dans laquelle débouchent les tubes et un couvercle. A titre d'exemple, le diamètre interne de chacun des collecteurs tubulaires peut être d'environ 400 mm.The tubular shape of the collectors 138 and 140 makes it possible to substantially reduce the thickness of the walls which constitute them, due to the reduction of the stresses generated in the wall by a given internal pressure, compared to the box-shaped collectors formed by a plate plane into which open the tubes and a cover. By way of example, the internal diameter of each of the tubular collectors can be around 400 mm.

Conformément à l'invention et comme le montre la fig. 6, l'accès aux extrémités 130 et 132 de chacun des tubes 120 s'effectue par des dispositifs d'accès 146 comprenant des orifices formés dans chacune des parties 134, 136 et normalement obturés par des bouchons amovibles 148. Il est ainsi possible d'avoir accès individuellement aux deux extrémités de chacun des tubes 120, sans qu'il soit nécessaire de munir les collecteurs 138 et 140 d'un couvercle de grande dimension dont l'étanchéité peut se révéler défectueuse lors du fonctionnement du réacteur. L'enveloppe 110 et les collecteurs 138 et 140 sont généralement disposés à l'intérieur d'un calorifuge (non représenté), et les dispositifs d'accès 146 font alors saillie à l'extérieur de ce calorifuge.According to the invention and as shown in FIG. 6, access to the ends 130 and 132 of each of the tubes 120 is effected by access devices 146 comprising orifices formed in each of the parts 134, 136 and normally closed by removable plugs 148. It is thus possible to '' have individual access to the two ends of each of the tubes 120, without the need to provide the collectors 138 and 140 with a large cover whose sealing may prove to be defective during operation of the reactor. The casing 110 and the collectors 138 and 140 are generally disposed inside a thermal insulation (not shown), and the access devices 146 then protrude outside of this thermal insulation.

Les collecteurs 138 et 140 ainsi que les parties externes 134 et 136 des tubes 120 sont symétriques, de sorte qu'on décrira seulement le collecteur d'entrée 138 et l'une des parties externes correspondantes 134 des tubes 120 en se référant à la fig. 3, avant de décrire un exemple de répartition dans l'espace de ces parties de tubes en se référant aux fig. 4 et 5.The manifolds 138 and 140 as well as the external parts 134 and 136 of the tubes 120 are symmetrical, so that only the inlet manifold 138 and one of the parts will be described. corresponding external 134 of the tubes 120 with reference to FIG. 3, before describing an example of the spatial distribution of these parts of tubes with reference to FIGS. 4 and 5.

Chacune des parties 134 présente une portion rectiligne 150 qui s'étend dans une direction sensiblement normale à l'enveloppe 110 du générateur de vapeur et une portion sensiblement verticale 152 formant un T avec la portion rectiligne 150 pour relier cette dernière au collecteur 138. Comme le montre la fig. 3, la portion rectiligne 150 de la partie externe 134 du tube 120 se termine par le dispositif d'accès 146, normalement obturé par le bouchon 148 comme l'illustre en particulier la fig. 6.Each of the parts 134 has a rectilinear portion 150 which extends in a direction substantially normal to the envelope 110 of the steam generator and a substantially vertical portion 152 forming a T with the rectilinear portion 150 for connecting the latter to the manifold 138. As shown in fig. 3, the straight portion 150 of the external part 134 of the tube 120 ends with the access device 146, normally closed by the plug 148 as illustrated in particular in FIG. 6.

La portion verticale 152 de la partie externe 134 est reliée à la portion rectiligne 150 à proximité du dispositif d'accès 146, de telle sorte que différents dispositifs de contrôle, de mesure, etc., peuvent être introduits dans la partie externe 134 au niveau du raccordement entre les portions 150 et 152 de chacune des parties externes des tubes, comme on le verra par la suite.The vertical portion 152 of the outer portion 134 is connected to the straight portion 150 near the access device 146, so that different control, measurement, etc. devices can be introduced into the outer portion 134 at the level of the connection between the portions 150 and 152 of each of the external parts of the tubes, as will be seen below.

Afin de ne pas modifier l'écoulement du fluide secondaire, la section interne des tubes 120 est de préférence constante, même au niveau des parties externes 134 et 136.In order not to modify the flow of the secondary fluid, the internal section of the tubes 120 is preferably constant, even at the level of the external parts 134 and 136.

Comme le montre en particulier la fig. 6, chacun des tubes comprend à l'extrémité de sa portion rectiligne 150, entourant le dispositif d'accès 146, une partie filetée 154 sur laquelle est vissé un écrou 156 au moyen duquel le bouchon correspondant 148, ou tout autre dispositif de contrôle ou de mesure, est sollicité contre l'extrémité annulaire de la portion rectiligne 150 du tube, de telle sorte qu'un joint annulaire 158 porté par le bouchon 148 engage cette extrémité de façon étanche. Afin d'éviter, notamment lors du serrage de l'écrou 156, la torsion de la portion rectiligne 150 des tubes, cette portion 150 est munie d'un dispositif antitorsion 160 (voir fig. 3), comprenant un tube dont une extrémité est fixée à l'enveloppe 110 du générateur par tout moyen approprié tel que, par exemple, par une soudure 162, et dont l'autre extrémité présente deux encoches diamétralement opposées 164 qui s'étendent dans une direction longitudinale par rapport au tube 160 et dans lesquelles pénètrent des doigts 166 s'étendant radialement vers l'extérieur à partir de l'extrémité de la portion rectiligne 150 dans laquelle est formé l'orifice d'accès 146. Bien entendu, le nombre d'encoches 164 et de doigts 166 peut être différent de deux et les doigts 166 peuvent être également rapportés sur la portion rectiligne 150 de la conduite. Le tube antitorsion 160 présente également dans sa partie inférieure une fente longitudinale 168 que traverse la portion verticale 152 du tube 120. Toute torsion de la portion rectiligne 150 de chacun des tubes 120, notamment lorsque l'écrou correspondant 156 est vissé ou dévissé, est ainsi empêchée à la fois au niveau de l'orifice d'accès 146 par la coopération des doigts 166 avec les encoches 164 et au niveau de la portion verticale 152 du tube 120, en raison de l'engagement de cette portion 152 avec les bords de la fente 168.As shown in particular in fig. 6, each of the tubes comprises, at the end of its rectilinear portion 150, surrounding the access device 146, a threaded part 154 on which is screwed a nut 156 by means of which the corresponding plug 148, or any other control device or measurement, is biased against the annular end of the straight portion 150 of the tube, so that an annular seal 158 carried by the plug 148 engages this end in a sealed manner. In order to avoid, in particular when tightening the nut 156, the twisting of the straight portion 150 of the tubes, this portion 150 is provided with an anti-torsion device 160 (see FIG. 3), comprising a tube, one end of which is fixed to the casing 110 of the generator by any suitable means such as, for example, by a weld 162, and the other end of which has two diametrically opposite notches 164 which extend in a longitudinal direction relative to the tube 160 and in which penetrate fingers 166 extending radially outward from the end of the straight portion 150 in which is formed the access orifice 146. Of course, the number of notches 164 and of fingers 166 can be different from two and the fingers 166 can also be attached to the straight portion 150 of the pipe. The anti-torsion tube 160 also has in its lower part a longitudinal slot 168 which the vertical portion 152 of the tube 120 crosses. Any twisting of the straight portion 150 of each of the tubes 120, in particular when the corresponding nut 156 is screwed or unscrewed, is thus prevented both at the level of the access orifice 146 by the cooperation of the fingers 166 with the notches 164 and at the level of the vertical portion 152 of the tube 120, due to the engagement of this portion 152 with the edges from slot 168.

Comme l'illustre également la fig. 3, la portion rectiligne 150 de chacune des parties externes 134 ou 136 des tubes 120 traverse l'enveloppe 110 du générateur de vapeur avec un certain jeu et elle est fixée à cette dernière par un manchon thermique 170 disposé à l'intérieur de l'enveloppe et fixé à celle-ci par tout moyen approprié tel que, par exemple, par soudure. Cette structure permet de compenser les déformations résultant de la dilatation des tubes et de l'enveloppe du générateur de vapeur.As also illustrated in fig. 3, the rectilinear portion 150 of each of the external parts 134 or 136 of the tubes 120 passes through the envelope 110 of the steam generator with a certain clearance and it is fixed to the latter by a thermal sleeve 170 placed inside the envelope and fixed thereto by any suitable means such as, for example, by welding. This structure makes it possible to compensate for the deformations resulting from the expansion of the tubes and of the envelope of the steam generator.

Conformément à une caractéristique secondaire de l'invention et afin de limiter les effets de la dilatation des parties externes 134 et 136 des tubes 120 sur les manchons thermiques 170 au moyen desquels les tubes sont fixés à l'enveloppe 110, chacune des portions verticales 152 présente la forme d'une lyre comme représenté en traits mixtes sur la fig. 3 et comme le montre plus précisément la fig. 4. Enfin, chacune des portions en dérivation 152 est fixée à la paroi du collecteur correspondant par tout moyen approprié tel que, par exemple, par soudure, et communique avec l'intérieur de ce collecteur par une ouverture radiale 172 formée dans la paroi de ce dernier.In accordance with a secondary characteristic of the invention and in order to limit the effects of the expansion of the external parts 134 and 136 of the tubes 120 on the thermal sleeves 170 by means of which the tubes are fixed to the casing 110, each of the vertical portions 152 has the shape of a lyre as shown in dashed lines in FIG. 3 and as shown more precisely in FIG. 4. Finally, each of the branch portions 152 is fixed to the wall of the corresponding collector by any suitable means such as, for example, by welding, and communicates with the interior of this collector by a radial opening 172 formed in the wall of this last.

Comme le montrent plus précisément les fig. 4 et 5, la répartition dans l'espace des parties externes 134 des tubes 120 demande un soin particulier en raison du grand nombre de tubes débouchant hors de l'enveloppe 110 de l'échangeur et de la forme particulière des parties externes 134 imposée par l'invention. Ainsi, dans le mode de réalisation représenté, les tubes 120 traversent l'enveloppe 110 en un certain nombre de nappes superposées (cinq sur les figures) et forment des rangées régulièrement réparties sur la circonférence de l'enveloppe, chaque rangée étant constituée par un tube de chaque nappe et les tubes de chaque rangée étant alignés selon une génératrice de l'enveloppe.As shown more precisely in figs. 4 and 5, the distribution in space of the external parts 134 of the tubes 120 requires special care due to the large number of tubes opening out of the casing 110 of the exchanger and the particular shape of the external parts 134 imposed by the invention. Thus, in the embodiment shown, the tubes 120 pass through the envelope 110 in a number of superimposed layers (five in the figures) and form rows regularly distributed over the circumference of the envelope, each row being constituted by a tube of each layer and the tubes of each row being aligned along a generatrix of the envelope.

Les portions rectilignes 150 de chacun des tubes font saillie radialement à l'extérieur de l'enveloppe 110 de l'échangeur, de telle sorte qu'elles se répartissent en cinq nappes superposées, définissant des rangées de cinq portions rectilignes régulièrement réparties à la périphérie de l'enveloppe. Les portions 152 débouchent latéralement sur les portions 150, comme le montre la fig. 5, de façon à pouvoir descendre verticalement entre les rangées formées par les tubes, l'embouchure de la portion 152 dans la portion 150 étant d'autant plus éloignée de l'enveloppe 110 que la portion 150 se trouve dans une nappe plus proche du collecteur 138 (voir fig. 4).The rectilinear portions 150 of each of the tubes protrude radially outside the casing 110 of the exchanger, so that they are distributed in five superimposed layers, defining rows of five rectilinear portions regularly distributed at the periphery of the envelope. The portions 152 open laterally on the portions 150, as shown in FIG. 5, so as to be able to descend vertically between the rows formed by the tubes, the mouth of the portion 152 in the portion 150 being all the more distant from the envelope 110 as the portion 150 is in a sheet closer to the manifold 138 (see fig. 4).

Dans le mode de réalisation représenté, les portions 152, correspondant à une même rangée de tubes, débouchent alternativement d'un côté et de l'autre des portions 150 (voir fig. 5), de telle sorte que les portions 152 correspondant à deux rangées voisines sont disposées en quinconce dans leurs parties verticales disposées entre ces rangées. Dans une variante (non représentée), les portions 152 peuvent déboucher toutes du même côté de la rangée des portions 150 qui leur correspond, et les parties verticales des portions 152 disposées entre deux rangées voisines correspondent alors toutes à une même rangée de tubes.In the embodiment shown, the portions 152, corresponding to the same row of tubes, open out alternately on one side and on the other of the portions 150 (see FIG. 5), so that the portions 152 corresponding to two neighboring rows are staggered in their vertical parts arranged between these rows. In a variant (not shown), the portions 152 can all open out on the same side of the row of portions 150 which corresponds to them, and the vertical parts of the portions 152 disposed between two adjacent rows then all correspond to the same row of tubes.

Dans les deux cas, les portions 152 correspondant à une même rangée de tubes sont ramenées dans le plan radial passant par les portions rectilignes 150 de cette rangée de tubes, pour y former des lyres de dilatation imbriquées (fig. 4). Les portions 152 de chaque rangée de tubes sont ensuite raccordées au collecteur 138, à égale distance les unes des autres, sur un secteur défini à la partie supérieure du collecteur, dans le même plan radial que les portions 150 qui leur correspondent.In both cases, the portions 152 corresponding to the same row of tubes are brought back in the radial plane passing through the rectilinear portions 150 of this row of tubes, to form there nested expansion lyres (FIG. 4). The portions 152 of each row of tubes are then connected to the manifold 138, at equal distance from each other, over a sector defined at the top of the manifold, in the same radial plane as the portions 150 which correspond to them.

En raison de la disposition des orifices d'accès 146 à l'extrémité de la portion rectiligne 150 de chacune des parties externes des tubes 120 et en raison de la forme particulière des portions verticales 152, l'accès de chacun des orifices est particulièrement aisé comme l'illustrent en particulier les fig. 3 et 4. Il est ainsi possible d'utiliser l'orifice d'accès formé dans chacune des portions rectilignes 150 pour réaliser, à l'arrêt, une inspection du tube par courants de Foucault ou un contrôle de l'étanchéité. Par ailleurs, on peut installer par cet orifice des dispositifs de réglage, de mesure ou de contrôle du fonctionnement du générateur, comme cela est explicité plus loin, dans la description des fig. 7 et 8.Because of the arrangement of the access openings 146 at the end of the straight portion 150 of each of the external parts of the tubes 120 and because of the particular shape of the vertical portions 152, the access from each of the openings is particularly easy as illustrated in particular in figs. 3 and 4. It is thus possible to use the access orifice formed in each of the rectilinear portions 150 to carry out, when stationary, an inspection of the tube by eddy currents or a tightness control. Furthermore, it is possible to install, through this orifice, devices for adjusting, measuring or controlling the operation of the generator, as explained below, in the description of FIGS. 7 and 8.

Ainsi, la fig. 3 illustre le remplacement de l'un des bouchons 148 par un dispositif de vérification de l'étanchéité du tube 120 correspondant, désigné par la référence générale 174. Ce dispositif est mis en place après refroidissement du générateur de vapeur et vidange du circuit secondaire. Il comprend essentiellement un embout tubulaire 176, s'étendant au-delà du raccordement en T de la portion 152, pour obturer celle-ci de façon étanche au moyen de deux joints annulaires 178 disposés de part et d'autre de l'embouchure de la portion verticale. L'embout tubulaire 176 comprend une collerette 180, serrée au moyen de l'écrou 156 contre l'extrémité libre de la portion rectiligne 150 du tube, dans laquelle est logé un organe poreux tel qu'une éponge 182 remplie par exemple d'eau savonneuse. L'enveloppe 110 du générateur de vapeur étant maintenue sous une légère pression effective d'argon, le dispositif 174 permet ainsi d'observer les bulles qui se forment dans l'eau savonneuse imprégnant l'éponge 182 à la sortie de l'embout tubulaire 176 en cas de fuite dans la paroi du tube 120 correspondant. Ce dispositif de détection de fuite n'est décrit qu'à titre d'exemple non limitatif et peut être remplacé par tout autre dispositif connu. Par exemple, en cas de microfuite nécessitant l'utilisation d'une méthode plus sensible, le dispositif décrit peut être utilisé différemment en imprégnant l'éponge 182 d'un réactif sensible à un gaz déterminé que l'on injecte dans l'argon à l'intérieur de l'enveloppe 110 du générateur de vapeur, ce gaz pouvant être par exemple de l'ammoniac. La coloration du réactif est alors observée à travers une plaque transparente 184 obturant en partie l'extrémité du dispositif 174. Un autre moyen de contrôle de l'étanchéité des tubes utilisant les orifices d'inspection 146 ménagés aux extrémités de chacun des tubes 120 consiste à injecter de l'hélium dans l'enveloppe 110 du générateur, à obturer l'une des extrémités du tube au moyen du bouchon 148 et à brancher un détecteur d'hélium d'un type connu à l'autre extrémité.Thus, fig. 3 illustrates the replacement of one of the plugs 148 by a device for checking the tightness of the corresponding tube 120, designated by the general reference 174. This device is put in place after the steam generator has cooled and the secondary circuit has been drained. It essentially comprises a tubular end-piece 176, extending beyond the T-shaped connection of the portion 152, for sealing the latter in a sealed manner by means of two annular seals 178 arranged on either side of the mouth of the vertical portion. The tubular endpiece 176 comprises a collar 180, tightened by means of the nut 156 against the free end of the straight portion 150 of the tube, in which is housed a porous member such as a sponge 182 filled, for example with water soapy. The envelope 110 of the steam generator being maintained under a slight effective pressure of argon, the device 174 thus makes it possible to observe the bubbles which form in the soapy water impregnating the sponge 182 at the outlet of the tubular nozzle. 176 in the event of a leak in the wall of the corresponding tube 120. This leak detection device is only described by way of nonlimiting example and can be replaced by any other known device. For example, in the event of a micro-leak requiring the use of a more sensitive method, the device described can be used differently by impregnating the sponge 182 with a reagent sensitive to a determined gas which is injected into the argon at inside the envelope 110 of the steam generator, this gas can for example be ammonia. The coloring of the reagent is then observed through a transparent plate 184 partially closing off the end of the device 174. Another means of checking the tightness of the tubes using the inspection orifices 146 formed at the ends of each of the tubes 120 consists to inject helium into the envelope 110 of the generator, to seal off one of the ends of the tube by means of the plug 148 and to connect a helium detector of a known type at the other end.

Sur la fig. 7, on a représenté l'hypothèse dans laquelle le bouchon 148 de l'un des tubes 134 ou 136 porte un support en doigt de gant 186 susceptible de recevoir un dispositif de mesure de température tel qu'un thermocouple connecté à un dispositif de mesure approprié et dont la partie sensible est disposée de préférence au niveau du raccordement de la portion verticale 152 sur la portion rectiligne 150. Le thermocouple susceptible d'être reçu dans le support en doigt de gant 186 porté par le bouchon 148 peut permettre, notamment, de mesurer la température de la vapeur d'eau surchauffée sortant d'un certain nombre de tubes 120 convenablement choisis.In fig. 7, the hypothesis has been shown in which the plug 148 of one of the tubes 134 or 136 carries a thermowell support 186 capable of receiving a temperature measurement device such as a thermocouple connected to a measurement device suitable and the sensitive part of which is preferably arranged at the connection of the vertical portion 152 on the rectilinear portion 150. The thermocouple capable of being received in the thermowell support 186 carried by the plug 148 may allow, in particular, to measure the temperature of the superheated steam leaving a certain number of tubes 120 suitably chosen.

Enfin, on a représenté sur la fig. 8 la portion rectiligne 150 de la partie externe 134 d'un tube 120 dont l'extrémité débouche dans le collecteur d'entrée 138, le bouchon 148 obturant l'orifice d'accès 146 formé dans la portion 150 portant un diaphragme 188 qui permet de stabiliser le débit d'eau circulant dans les tubes 120 du générateur de vapeur. Le diaphragme 188 est formé I'extrémitéd'un organetubulaire 190 porté par le bouchon 148 et s'étendant au-delà de la jonction entre la portion verticale 1.52 et la portion rectiligne 150 de la partie 134. L'organe tubulaire 190 est ajouré latéralement au moyen de trous 192 formés au niveau de la portion verticale 152, et un joint d'étanchéité annulaire 184 est disposé entre l'organe tubulaire 190 et la portion rectiligne 150 du tube entre la portion en dérivation 152 et l'enveloppe 110 du générateur de vapeur, de telle sorte que l'eau provenant du collecteur d'entrée 138 et pénétrant dans la portion rectiligne 150 par la portion 152 doit traverser les trous 192 et le diaphragme 188 avant de pénétrer à l'intérieur du générateur de vapeur. Le contrôle et le remplacement éventuel des diaphragmes 188 peut ainsi être effectué de façon particulièrement simple. Bien entendu, le diaphragme 188 peut être remplacé par tout dispositif créant une perte de charge analogue.Finally, there is shown in FIG. 8 the rectilinear portion 150 of the external portion 134 of a tube 120 whose end opens into the inlet manifold 138, the plug 148 closing the access orifice 146 formed in the portion 150 carrying a diaphragm 188 which allows to stabilize the flow of water circulating in the tubes 120 of the steam generator. The diaphragm 188 is formed at the end of a tubular organ 190 carried by the plug 148 and extending beyond the junction between the vertical portion 1.52 and the straight portion 150 of the portion 134. The tubular member 190 is perforated laterally by means of holes 192 formed at the vertical portion 152, and an annular seal 184 is disposed between the tubular member 190 and the straight portion 150 of the tube between the branch portion 152 and the casing 110 of the generator vapor, so that the water from the inlet manifold 138 and entering the straight portion 150 through the portion 152 must pass through the holes 192 and the diaphragm 188 before entering the interior of the steam generator. The control and possible replacement of the diaphragms 188 can thus be carried out in a particularly simple manner. Of course, the diaphragm 188 can be replaced by any device creating a similar pressure drop.

Bien entendu, les dispositifs de mesure et de contrôle qui viennent d'être décrits à titre d'exemple ne sont pas limitatifs des possibilités d'accès aux extrémités des tubes du générateur de vapeur résultant de la présente invention. En particulier, le démontage de chacun des bouchons 148 peut permettre après refroidissement et vidange du générateur l'introduction de tous dispositifs de mesure ou de contrôle connus tels que, par exemple, une sonde à courants de Foucault ou à ultrasons permettant l'inspection de chacun des tubes. En outre, l'invention n'est pas limitée à un générateur de vapeur et concerne tous les échangeurs dans lesquels la chaleur véhiculée par un fluide primaire est utilisée pour échauffer un fluide secondaire.Of course, the measurement and control devices which have just been described by way of example are not limiting of the possibilities of access to the ends of the tubes of the steam generator resulting from the present invention. In particular, the dismantling of each of the plugs 148 may allow after cooling and emptying of the generator the introduction of any known measurement or control devices such as, for example, an eddy current or ultrasonic probe allowing the inspection of each of the tubes. Furthermore, the invention is not limited to a steam generator and concerns all the heat exchangers geurs in which the heat conveyed by a primary fluid is used to heat a secondary fluid.

Claims (11)

1. Heat exchanger comprising a shell (110) in which heat carried by a primary fluid is transferred to and warms a secondary fluid, which secondary fluid circulates in tubes (120) whose opposite ends open respectively into tubular inlet (138) and outlet manifolds (140) disposed externally of the shell of said exchanger and surrounding at least a portion thereof, at least one access port (146) closed by a detachable stopper (148) being provided for each of the tubes, characterized in that each of the tubes (120) comprises two access ports (146) each closed by a detachable stopper (148), each access port being located in a portion (134, 136) of the tube situated between the shell (110) of the exchanger and the corresponding manifold (138,140).
2. Heat exchanger according to claim 1, characterized in that each of the tube portions (134,136) comprises a first straight part (150) ending in the access port (146), and a second part (152) forming a T with the straight part and connecting the latter with the corresponding manifold (138, 140).
3. Heat exchanger according to claim 2, characterized in that the straight part (150) of each of said tube portions extends substantially normally of the exchanger shell (110).
4. Heat exchanger according to claim 2 or 3, characterized in that the second part (152) or each of said tube portions is connected to the straight part near the corresponding access port (146).
5. Heat exchanger according to claim 4, characterized in that the stopper (148) closing the access port (146) located in the portion (134) of each of the tubes between the exchanger shell and the inlet manifold (138) carries a tube (190) extending into the straight part (150) of said tube portion beyond the junction with the second part (152) of said tube portion, said tube having lateral perforations (192) adjacent the junction with said second part, and having a diaphragm (188) or analogous pressure-reduction means beyond the latter.
6. Heat exchanger according to any one of claims 2 to 5, characterized in that the second part (152) of each of said tube portions forms an expansion band.
7. Heat exchanger according to any one of claims 2 to 6, characterized in that the straight part (150) of each of said tube portions is surrounded by an antitorsion device (160) one end of which is fixed to the shell of the exchanger and whose other end has at least one longitudinal notch (164) engageable with a finger (166) unitary with the straight part near the access port (146), the antitorsion device comprising at least one longitudinal slot for the second part (152) of the corresponding tube portion.
8. Heat exchanger according to any one of the preceding claims, characterized in that each of said tube portions (134, 136) has a threaded section (154) surrounding the access port (146) on which is screwed a nut (156) by means of which the corresponding stopper (148) is urged against the access port in fluid-tight fashion.
9. Heat exchanger according to any one of the preceding claims, characterized in that at least one of the stoppers (148) closing the access ports carries a temperature sensor (186).
10. Heat exchanger according to any one of the preceding claims, characterized in that at least one of the stoppers (148) closing the access ports carries a fluid control valve.
11. Heat exchanger according to any one of the preceding claims, characterized in that the shell (110) of the exchanger and the manifolds (138, 140) are at least partially enclosed by insulation and the access ports (146) are outside the insulation.
EP80400200A 1979-02-14 1980-02-08 Heat exchanger Expired EP0015191B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR7903746 1979-02-14
FR7903746A FR2449260A1 (en) 1979-02-14 1979-02-14 HEAT EXCHANGER

Publications (2)

Publication Number Publication Date
EP0015191A1 EP0015191A1 (en) 1980-09-03
EP0015191B1 true EP0015191B1 (en) 1982-12-01

Family

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EP80400200A Expired EP0015191B1 (en) 1979-02-14 1980-02-08 Heat exchanger

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US (1) US4311189A (en)
EP (1) EP0015191B1 (en)
JP (1) JPS55137402A (en)
DE (1) DE3061174D1 (en)
FR (1) FR2449260A1 (en)

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2509433A1 (en) * 1981-07-08 1983-01-14 Electricite De France DEVICE FOR DETECTING LEAKS IN A STEAM GENERATOR
FR2524609A1 (en) * 1982-03-31 1983-10-07 Novatome EMERGENCY SHUT-OFF DEVICE IN THE EVENT OF LEAKAGE OF A TUBE OF A STEAM GENERATOR
JPS59150202A (en) * 1983-02-16 1984-08-28 バブコツク日立株式会社 Recovery device for waste heat
FR2549935B1 (en) * 1983-07-28 1985-10-25 Novatome STEAM OUTLET CONNECTION FOR STEAM GENERATOR
JPS6081407U (en) * 1983-11-02 1985-06-06 バブコツク日立株式会社 Boiler heat exchanger tube structure
DE4225827A1 (en) * 1992-08-05 1994-02-10 Forbach Gmbh Open hot water tank
JP3028941B2 (en) * 1997-10-22 2000-04-04 核燃料サイクル開発機構 Multi-sheath type sodium leak detection device
US20040069470A1 (en) * 2002-09-10 2004-04-15 Jacob Gorbulsky Bent-tube heat exchanger
US20100258062A1 (en) * 2009-04-14 2010-10-14 Cliff Berry Cold water pre-heater
US9631807B2 (en) 2014-09-22 2017-04-25 University Research Glassware Corporation Continuous ultrapure steam generator

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Publication number Priority date Publication date Assignee Title
US2110024A (en) * 1936-08-29 1938-03-01 Gen Electric Heat exchange unit
US3112735A (en) * 1959-03-30 1963-12-03 Babcock & Wilcox Co Liquid metal heated vapor generator
FR1352958A (en) * 1963-01-09 1964-02-21 Henri Lardet Atel Improvement in steam and superheated water generators
US3319657A (en) * 1964-10-16 1967-05-16 Louis A Nyiri Coil freeze protection device
FR2112007A1 (en) * 1970-04-03 1972-06-16 Edf Tube bundle heat exchanger - has internal reservoir to contain overflow surges due to leaks
US3941187A (en) * 1971-07-14 1976-03-02 The Babcock & Wilcox Company Consolidated nuclear steam generator
US3848572A (en) * 1971-08-09 1974-11-19 Westinghouse Electric Corp Steam generator
JPS5844921B2 (en) * 1974-08-19 1983-10-06 株式会社日立製作所 joukihatsuseiki
FR2379881A1 (en) * 1977-02-04 1978-09-01 Commissariat Energie Atomique HEAT EXCHANGER PUMP UNIT FOR NUCLEAR REACTORS

Also Published As

Publication number Publication date
JPS55137402A (en) 1980-10-27
FR2449260B1 (en) 1982-12-17
DE3061174D1 (en) 1983-01-05
EP0015191A1 (en) 1980-09-03
US4311189A (en) 1982-01-19
FR2449260A1 (en) 1980-09-12

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