EP0057643A2 - Schutzeinrichtung für die Rohrplatte an der heissen Seite eines vertikaler Wärmetauschers - Google Patents

Schutzeinrichtung für die Rohrplatte an der heissen Seite eines vertikaler Wärmetauschers Download PDF

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Publication number
EP0057643A2
EP0057643A2 EP82400166A EP82400166A EP0057643A2 EP 0057643 A2 EP0057643 A2 EP 0057643A2 EP 82400166 A EP82400166 A EP 82400166A EP 82400166 A EP82400166 A EP 82400166A EP 0057643 A2 EP0057643 A2 EP 0057643A2
Authority
EP
European Patent Office
Prior art keywords
tubes
plate
zone
plates
tube plate
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.)
Granted
Application number
EP82400166A
Other languages
English (en)
French (fr)
Other versions
EP0057643A3 (en
EP0057643B1 (de
Inventor
Pierre Pouderoux
Guy Salon
Thong Nguyen-Thanh
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.)
Stein Industrie SA
Commissariat a lEnergie Atomique et aux Energies Alternatives CEA
Original Assignee
Stein Industrie SA
Commissariat a lEnergie Atomique CEA
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Stein Industrie SA, Commissariat a lEnergie Atomique CEA filed Critical Stein Industrie SA
Publication of EP0057643A2 publication Critical patent/EP0057643A2/de
Publication of EP0057643A3 publication Critical patent/EP0057643A3/fr
Application granted granted Critical
Publication of EP0057643B1 publication Critical patent/EP0057643B1/de
Expired legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F19/00—Preventing the formation of deposits or corrosion, e.g. by using filters or scrapers
    • 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
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F21/00—Constructions of heat-exchange apparatus characterised by the selection of particular materials
    • F28F21/08—Constructions of heat-exchange apparatus characterised by the selection of particular materials of metal
    • F28F21/081—Heat exchange elements made from metals or metal alloys
    • F28F21/082—Heat exchange elements made from metals or metal alloys from steel or ferrous alloys
    • F28F21/083—Heat exchange elements made from metals or metal alloys from steel or ferrous alloys from stainless steel
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F9/00—Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings
    • F28F9/02—Header boxes; End plates
    • F28F9/0229—Double end plates; Single end plates with hollow spaces

Definitions

  • the present invention relates to a heat exchanger, the hot end of which is provided with a device for protecting the tube plate. More specifically, the invention relates to a heat exchanger comprising an external shell closed at its ends. hot and cold by two tube plates, a bundle of tubes connected to the tube plates to open into inlet and outlet manifolds of .a fluid such as 1- eaù.circulant the inside of the tubes and inlet and outlet pipes for a liquid, such as an alkaline liquid metal, circulating in said ferrule and around the tubes.
  • a fluid such as 1- eaù.circulant the inside of the tubes and inlet and outlet pipes for a liquid, such as an alkaline liquid metal, circulating in said ferrule and around the tubes.
  • the object of the present invention is to remedy these drawbacks, and to provide a device for protection of the tube plate at the hot end of the exchanger, which reduces the temperature of the liquid alkali metal coming into direct contact with it, without however reducing the temperature of the superheated steam reaching the tube plate, which reduces the thermal stresses therein during changes in the regime of the installation, and which nevertheless ensures the circulation of alkali metal around the nipples joining the tubes with the tube plate. It also aims to allow the tube plate to be made of a ferritic steel with a relatively low chromium content, and to ensure a scanning of the welds of the tubes on the junction nipples by the alkali metal in circulation, which facilitates the detection of possible leaks.
  • the heat exchanger is characterized in that it comprises, at its hot end, a device for protecting the tube plate, this device comprising two plates, joined by a ferrule to define a first zone filled with said liquid in the static state forming a heat shield, said plates being substantially parallel to the tube plate and a first of these plates being disposed near the tube plate, the protection device further comprising through passages said zone from one plate to another and means for creating a vacuum between said first plate and the tube plate, in order to ensure a circulation of said liquid towards the tube plate inside said passages.
  • the exchanger comprises an outer shroud 1, with a vertical axis, closed at its upper and lower ends by tube plates 2, 2 'to which the tubes such as 4 of a bundle of tubes are connected straight arranged inside the ferrule 1.
  • These tubes open respectively, at the lower part of the exchanger, in an inlet manifold 3 'of the water of the secondary circuit and at its upper part, in a manifold of outlet 3 of the vaporized water.
  • the water to be vaporized therefore circulates from bottom to top inside the tubes 4 between the collectors 3 'and 3.
  • the liquid metal (generally sodium) circulating in the primary circuit of the exchanger moves against the current with respect to the water of the primary circuit, that is to say from top to bottom, inside the ferrule 1 and around the tubes 4, between an inlet pipe 6 and an outlet pipe 6 '.
  • the hottest area of the exchanger is therefore its upper part into which the liquid metal penetrates, and this part will now be described in more detail with reference to FIG. 2.
  • FIG. 2 it can be seen in FIG. 2 that the upper part of the bundle of tubes 4 is surrounded by a thin internal ferrule 5 at the level of the inlet manifold 6 of the hot liquid sodium.
  • the ferrule 5 is connected to the external ferrule 1 below the tubing 1 and its upper end ends near the protection device according to the invention, so that the hot liquid sodium rises through an annular zone 6A defined between ferrules 1 and 5, before to descend into the zone 6B internal to the shell 5, around the tubes 4 of the bundle, against the current of the water circulating in these tubes.
  • the device for protecting the tube plate 2, part of which is visible on a larger scale in FIG. 5, comprises a first flat plate 7 parallel to the tube plate 2 or, in other terms, perpendicular to the axis of the exchanger, and located above the upper end of the internal ferrule 5.
  • the plate 7 is fixed by its periphery to the external ferrule 1 by means of a cylindrical ferrule 7A provided with a lower rim welded to the internal wall of the external shell.
  • the protective device according to the invention further comprises a second planar plate 8 parallel to the first plate 7 and disposed above the latter, near the underside of the tube plate 2 through which the tubes 4 penetrate. .
  • the plate 8 extends over the entire surface of the tube plate 2.
  • the plates 7 and 8 are connected at the periphery of the plate 8, by a cylindrical ferrule thin 9 welded to these plates.
  • the zone 13A thus defined between the plates 7 and 8 and the shell 9 is filled with practically static sodium playing the role of thermal shield between the hot sodium admitted by the tube 6 and the tube plate 2.
  • the tubes 4 of the tube bundle pass through the plates 7, 10 and 8 inside the sheaths 12 welded to the plate 7 and pass through the plates 10 and 8.
  • the sheaths 12 define with the tubes 4 annular passages through which the sodium hot liquid can circulate upwards from the zone 6B of the exchanger situated below the plate 7, up to the tube plate 2 and the annular zone 13 delimited around the zone 13A and separated from the rest of the exchanger by ferrule 7A. More precisely, and as illustrated in FIG. 4, the annular passages defined between the sleeves 12 and the tubes 4 open out above the zone 13A forming a heat shield near the nipples 20 of the tube plate on which are welded tubes.
  • this structure is found over the entire extent of the tube plate 2, so that the upward circulation of hot liquid sodium has the effect of ensuring an efficient scanning of the welds of the tubes on the nipples 20. From more, the liquid sodium cools during its passage in the sleeves 12, by heat exchange with the water circulating in the tubes so that it reaches the level of these welds at a temperature substantially lower than that which it had at the time. of its entry into the exchanger.
  • the upward circulation of liquid sodium in the passages defined between the tubes 4 and the sleeves 12 is obtained by creating a depression in the area 13, with respect to the pressure prevailing in the area of sodium circulation below the plate 7.
  • the zone 13 is connected to an annular zone 18 by a series of vertical tubes 16, crossing the zone 6A between the ferrules 1 and 5.
  • the tubes 16 are welded on lugs 17 fixed on the internal ferrule 5.
  • the zone 18 is located below and separated from the zone 6A by a partition 19, and it communicates with a part 22 of the zone 6B internal to the shell 5 by orifices 21 formed in the latter, close to the junction of its lower end with the external shell 1.
  • Part 22 of the zone 6B is located downstream of the part situated immediately below the plate 7, so that the pressure of the liquid sodium is lower there, due to the loss of charge.
  • zones 13 and 13A are carried out first of all by means of holes 7B formed in the rim of the shell 7A welded to the external shell 1 and allowing the liquid sodium to enter during filling, to leave during emptying, while practically preventing any significant circulation during the operation of the exchanger.
  • the ferrule 9 has at its lower part orifices 9A, and there is a clearance 8A between the sleeves 12 and the plate 8.
  • annular zone 13 surrounding the end of the tube plate is connected by a tube 14 to a reserve of argon.
  • a perforated torus 15 for sampling sodium for analysis is connected by a tube 15A to an analysis apparatus (not shown), intended to detect possible leaks from the welds of the tubes 4 on the teats 20.
  • the protection device which has just been described brings the temperature of the liquid sodium back in direct contact with the tube plate at around 500 ° C.
  • This allows the use of ferritic steel tube plates, 2.25% chromium and 1% molybdenum, instead of austenitic steel, while avoiding decarburization ferritic steel by hot sodium, which would be significant at 525 ° C.
  • the device for protection by the parallel thin plates protects the tube plate against thermal shocks resulting from transient operating conditions, and allows it to be assigned a higher permissible working rate than if it were directly in contact with hot sodium at 525 ° C, in particular with regard to teats 20.
  • the sodium circulation ensured by the depression created in the annular zone surrounding the tube plate makes it possible to ensure an efficient scanning of the welds of the tubes of the bundle to the nipples of the tube plate, and consequently a very rapid detection of any leakage from these welds.
  • the invention has been described on a heat exchanger in which the heating fluid is liquid sodium and the heated fluid in water, but it is understood that it relates in particular to steam generators heated by liquid metals and , more generally, to heat exchangers with tube outlets by tube plates, ferrules or manifolds.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • High Energy & Nuclear Physics (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Sustainable Development (AREA)
  • Sustainable Energy (AREA)
  • Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
  • Details Of Heat-Exchange And Heat-Transfer (AREA)
EP82400166A 1981-02-02 1982-01-29 Schutzeinrichtung für die Rohrplatte an der heissen Seite eines vertikaler Wärmetauschers Expired EP0057643B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8101954A FR2499212A1 (fr) 1981-02-02 1981-02-02 Dispositif de protection de la plaque tubulaire a l'extremite chaude d'un echangeur de chaleur vertical
FR8101954 1981-02-02

Publications (3)

Publication Number Publication Date
EP0057643A2 true EP0057643A2 (de) 1982-08-11
EP0057643A3 EP0057643A3 (en) 1982-08-25
EP0057643B1 EP0057643B1 (de) 1984-07-04

Family

ID=9254733

Family Applications (1)

Application Number Title Priority Date Filing Date
EP82400166A Expired EP0057643B1 (de) 1981-02-02 1982-01-29 Schutzeinrichtung für die Rohrplatte an der heissen Seite eines vertikaler Wärmetauschers

Country Status (6)

Country Link
US (1) US4418748A (de)
EP (1) EP0057643B1 (de)
JP (1) JPS57148197A (de)
DE (1) DE3260305D1 (de)
ES (1) ES509230A0 (de)
FR (1) FR2499212A1 (de)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0070758A1 (de) * 1981-07-08 1983-01-26 Electricite De France Dampferzeuger mit einer Vorrichtung zur Ermittlung von Undichtheiten
EP0136127A2 (de) * 1983-09-28 1985-04-03 National Nuclear Corporation Limited Bemantelter Rohrbündel-Wärmetauscher
FR2576708A1 (fr) * 1985-01-25 1986-08-01 Novatome Generateur de vapeur dont le fluide caloporteur est du metal liquide et dont la detection des fuites est effectuee par prelevement de ce metal liquide
FR2683897A1 (fr) * 1991-11-19 1993-05-21 Framatome Sa Echangeur de chaleur a tubes droits perfectionne dans lequel circule un fluide a temperature elevee et variable.
DE202012104092U1 (de) 2011-12-21 2012-11-19 Roman Aschl Fluidventil

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2518707A1 (fr) * 1981-12-18 1983-06-24 Novatome Dispositif de production de vapeur par echange de chaleur entre un metal liquide caloporteur et de l'eau alimentaire
US4585053A (en) * 1982-09-02 1986-04-29 The United States Of America As Represented By The United States Department Of Energy Heat exchanger for reactor core and the like
FR2548345B1 (fr) * 1983-07-01 1985-10-18 Commissariat Energie Atomique Echangeur de chaleur c
FR2599133B1 (fr) * 1986-05-21 1990-09-21 Struthers Wells Sa Echangeur de chaleur tubulaire a double plaque de support du faisceau de tube
GB2204942B (en) * 1987-04-07 1991-08-21 Nat Nuclear Corp Ltd Heat exchangers
SE506894C2 (sv) * 1995-12-04 1998-02-23 Edmeston Ab Rörvärmeväxlare med dubbelväggig mantel och förfarande och anläggning för tillverkning av kimrök
US20160215735A1 (en) * 2013-09-11 2016-07-28 International Engine Intellectual Property Company, Llc Thermal screen for an egr cooler
CN105865232A (zh) * 2016-05-18 2016-08-17 无锡华精新材股份有限公司 一种列管换热器

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3245464A (en) * 1963-02-28 1966-04-12 Babcock & Wilcox Co Liquid metal heated vapor generator
FR1536825A (fr) * 1967-09-15 1968-08-16 Babcock & Wilcox Ltd Perfectionnements aux échangeurs de chaleur
FR2010568A1 (de) * 1968-06-10 1970-02-20 Westinghouse Electric Corp
DE2713668A1 (de) * 1976-03-29 1977-11-03 Hitachi Ltd Roehrenwaermetauscher und verfahren zu dessen zusammenbau

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1225967A (de) * 1967-03-22 1971-03-24
NL6807673A (de) * 1968-05-30 1969-12-02
US3811498A (en) * 1972-04-27 1974-05-21 Babcock & Wilcox Co Industrial technique
JPS5234775A (en) * 1975-09-12 1977-03-16 Tsuneo Washimi Colorific meter
JPS5741594A (en) * 1980-08-25 1982-03-08 Hitachi Ltd Heat shield plate structure for heat exchanger

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3245464A (en) * 1963-02-28 1966-04-12 Babcock & Wilcox Co Liquid metal heated vapor generator
FR1536825A (fr) * 1967-09-15 1968-08-16 Babcock & Wilcox Ltd Perfectionnements aux échangeurs de chaleur
FR2010568A1 (de) * 1968-06-10 1970-02-20 Westinghouse Electric Corp
DE2713668A1 (de) * 1976-03-29 1977-11-03 Hitachi Ltd Roehrenwaermetauscher und verfahren zu dessen zusammenbau

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0070758A1 (de) * 1981-07-08 1983-01-26 Electricite De France Dampferzeuger mit einer Vorrichtung zur Ermittlung von Undichtheiten
EP0136127A2 (de) * 1983-09-28 1985-04-03 National Nuclear Corporation Limited Bemantelter Rohrbündel-Wärmetauscher
EP0136127A3 (en) * 1983-09-28 1985-12-18 National Nuclear Corporation Limited Tube-in-shell heat exchangers
FR2576708A1 (fr) * 1985-01-25 1986-08-01 Novatome Generateur de vapeur dont le fluide caloporteur est du metal liquide et dont la detection des fuites est effectuee par prelevement de ce metal liquide
EP0190075A1 (de) * 1985-01-25 1986-08-06 Novatome Dampferzeuger mit flüssigem Metall als Wärmetransportmittel und mit Leckfeststellung durch Entnahme eines solchen flüssigen Metalles
FR2683897A1 (fr) * 1991-11-19 1993-05-21 Framatome Sa Echangeur de chaleur a tubes droits perfectionne dans lequel circule un fluide a temperature elevee et variable.
DE202012104092U1 (de) 2011-12-21 2012-11-19 Roman Aschl Fluidventil

Also Published As

Publication number Publication date
EP0057643A3 (en) 1982-08-25
ES8401599A1 (es) 1983-12-16
ES509230A0 (es) 1983-12-16
JPS57148197A (en) 1982-09-13
JPH0231320B2 (de) 1990-07-12
FR2499212A1 (fr) 1982-08-06
EP0057643B1 (de) 1984-07-04
FR2499212B1 (de) 1985-02-22
DE3260305D1 (en) 1984-08-09
US4418748A (en) 1983-12-06

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