EP0165846B1 - Flüssigkeitsinjektionseinrichtung in einem Rohr und Dampferzeuger mit solcher Einrichtung - Google Patents

Flüssigkeitsinjektionseinrichtung in einem Rohr und Dampferzeuger mit solcher Einrichtung Download PDF

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Publication number
EP0165846B1
EP0165846B1 EP85401000A EP85401000A EP0165846B1 EP 0165846 B1 EP0165846 B1 EP 0165846B1 EP 85401000 A EP85401000 A EP 85401000A EP 85401000 A EP85401000 A EP 85401000A EP 0165846 B1 EP0165846 B1 EP 0165846B1
Authority
EP
European Patent Office
Prior art keywords
tube
cannula
centering
cone
fluid
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
EP85401000A
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English (en)
French (fr)
Other versions
EP0165846A1 (de
Inventor
Jean Edmond Chaix
Michel Metteey
Jean-Paul Badoux
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
Original Assignee
Commissariat a lEnergie Atomique CEA
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Publication of EP0165846A1 publication Critical patent/EP0165846A1/de
Application granted granted Critical
Publication of EP0165846B1 publication Critical patent/EP0165846B1/de
Expired legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22—STEAM GENERATION
    • F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
    • F22B21/00—Water-tube boilers of vertical or steeply-inclined type, i.e. the water-tube sets being arranged vertically or substantially vertically
    • F22B21/22—Water-tube boilers of vertical or steeply-inclined type, i.e. the water-tube sets being arranged vertically or substantially vertically built-up from water tubes of form other than straight or substantially straight
    • F22B21/26—Water-tube boilers of vertical or steeply-inclined type, i.e. the water-tube sets being arranged vertically or substantially vertically built-up from water tubes of form other than straight or substantially straight bent helically, i.e. coiled
    • 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
    • F22B37/18—Inserts, e.g. for receiving deposits from water
    • 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
    • F22B37/72—Arrangements for distributing water into water tubes involving injection devices

Definitions

  • the present invention relates to a device for injecting a liquid into a tube comprising a cannula disposed in said tube, this cannula comprising, in the direction of injection of the fluid, a passage of narrowed section followed by a divergent. It is particularly applicable to the injection of water into a steam generator, in particular of the single pass type with vertical penetration.
  • Single-pass helical steam generators have a pressure-resistant jacket containing coiled tubes.
  • a first heat transfer fluid called the primary fluid circulates outside these tubes.
  • a secondary fluid flows through the network of tubes. It enters through the cover of the envelope into the tubes by thermal sleeves which pass through a tube plate, then descends by bundles of straight tubes placed in the central area of the steam generator to the base of the tubes wound by which it rises and leaves in the form of vapor through sleeves which pass through the cover at its periphery.
  • the flow rate of the secondary fluid can be the seat of instabilities which appear particularly in low power conditions and which seriously disturb the operation of the device.
  • a device for injecting a liquid into a tube of the type defined above is already known (US-A-4191 246).
  • This device comprises a cannula placed in the tube, and which has, in the direction of injection of the fluid, a passage of narrowed section followed by a divergent.
  • this device does not apply to the problem which is the basis of the invention. Its purpose is to reduce the heat transfer between the secondary fluid which circulates outside the tubes of the exchanger and the primary fluid which circulates inside these tubes at the orifices of passage of the tube plates.
  • the cannula is only a sleeve which has the function of partially isolating the wall of the tube from the primary fluid which circulates there.
  • the invention relates to a device for injecting a fluid into a tube which overcomes these drawbacks.
  • This device is characterized in that it comprises a cannula disposed in said tube, said cannula comprising, in the direction of injection of the fluid, a passage of narrowed cross section relative to the diameter of the tube followed by a diverging portion at its bottom , and in that the means for centering and immobilizing in translation the cannula on the tube are constituted by a cylindrical centering part for centering the sheath in the tube, at least one slot and an internal cone formed in the sheath at its lower part , by an outer cone formed in the lower part of the cannula, the inner cone and the outer cone being adapted to cooperate, means being provided for resiliently applying the outer cone to the inner cone.
  • the cross section of the fluid in the cannula is determined in such a way that the speed of this fluid is greater than 0.7 m / s.
  • the invention relates to a steam generator.
  • This generator comprises an envelope, a tube plate, located inside the envelope and dividing the envelope into a water box and a heat exchange zone, an inlet, and an outlet for a primary fluid, located in the heat exchange zone of the enclosure, an inlet and an outlet for a secondary fluid, located in the water box, a plurality of vertical tubes having an inlet end and an outlet end for the secondary fluid, said inlet and outlet ends being fixed to the tube plate, each tube comprising a rectilinear part on the side of its inlet end, a device for injecting the secondary fluid into a tube comprising a cannula disposed inside from the inlet end of a tube and having a passage section narrowed relative to the diameter of the tube for the secondary fluid.
  • Said passage section of the cannula is followed, in the direction of circulation of the secondary fluid, by a diverging portion at its lower part, a sheath being coaxially disposed between said cannula and the straight part of the tube, means being provided for centering the cannula relative to this straight part of the tube.
  • the means for centering and immobilizing in translation the cannula on the tube are constituted by a cylindrical centering part, for centering the sheath in the tube, at least one slot and an internal cone formed in the sheath. at its lower part, by an outer cone formed at the lower part of the cannula, the inner cone and the outer cone being adapted to cooperate, means being provided for elastically applying the outer cone to the inner cone.
  • FIG 1 is a sectional and perspective view of a steam generator of the single pass type with vertical penetration equipped with an injection device produced in accordance with the present invention; this generator, designated by the general reference 2, comprises a pressure-resistant casing 4, of generally elongated cylindrical shape and of vertical axis.
  • the envelope 4 has a curved bottom 11. It is closed at its upper part by a cover 6. Between the cover and the envelope is a thick plate 8 called tube plate.
  • the cover 6 has a domed shape which delimits a volume 7 called "water box".
  • the water box 7 is divided into two zones by the ferrule 16, a circular central zone for the entry of water and an annular zone for the exit of steam.
  • a line 18 evacuates the vapor.
  • Each tube has a straight part 10a arranged vertically and fixed to the tube plate.
  • the straight part 10a ends in a bend which connects it to a spiral part 10b connected to the peripheral zone of the tube plate 8.
  • An inlet 4a and an outlet 4b are arranged in the casing 4 to allow the circulation of a primary fluid.
  • a secondary fluid circulates inside the network of tubes 10.
  • the secondary fluid for example water, penetrates in the direction indicated by the arrow 14 and then into the water box 7 in the right part 10a of the tubes 10.
  • the flow rate of the secondary fluid can be the seat of instabilities in low power conditions.
  • the Applicant has been able to establish that during its fall into the straight tubes, the water heats up and has time to reach its saturation temperature. Consequently, vapor bubbles are formed which tend to flow up the current too weak to entrain them. These bubbles accumulate at the entrance of the steam generator in the central area of the water box 7 and form there a mattress of steam, which abruptly condenses on contact with cold water which enters the steam generator. . This brutal condensation produces a depression which causes a reversal of the flow by sucking up the water which has just been injected. This transient phenomenon is followed by a return to normal conditions and the sequence begins periodically.
  • the invention relates to a device for injecting a fluid into a tube which eliminates this phenomenon. This result is obtained by increasing the injection speed so that the water does not have time to reach its saturation temperature during its passage through the straight tubes 10a. Tests have shown that for a steam generator such as that shown in FIG. 1, the injection speed must be greater than 0.7 m / s.
  • FIG. 2 shows a sectional view of a preferred embodiment of an injection device of the invention.
  • Reference 8 designates the tube plate and reference 10a a tube fixed in this tube plate.
  • the tube 10a is surmounted by a head piece 228. This piece is fixed to the tube by forced fitting or by welding.
  • the injection device comprises a cannula 220 constituted by a tube comprising a central duct 238 of reduced section and the diameter of which has been determined so that the speed of the secondary fluid is always greater than 0.7 m / sec.
  • the cannula 220 has a divergent 222 making it possible to increase the passage section offered to the fluid and consequently to reduce its speed to a low value, so as not to produce erosion in the bend of the tube located immediately downstream of the cannula.
  • the piece added by welding, in which the diverging part 222 is made, externally has a conical part 250 intended for centering and immobilizing the cannula relative to the tube 10a.
  • the cannula has a threaded part 260.
  • a clamping ring 262 is screwed onto the threaded part 260.
  • the ring 262 is immobilized by a lock nut 264 stopped in rotation in a known manner.
  • the cannula 220 is surrounded by a sheath 220 'which has an outer shoulder 221'.
  • the part on which the shoulder 221 ′ is produced is attached by welding to the main part of the sheath.
  • the sheath At its lower part, the sheath has a cylindrical centering part 226 ′ whose outside diameter is close to the inside diameter of the tube 10a.
  • the sheath also has a female cone 250 'adapted to cooperate with the male cone 250 of the cannula.
  • the head piece 228 has an internal shoulder intended to support the shoulder 221 ′ of the sheath.
  • a plug 230 is screwed into an internal threaded part of the head piece. This plug tightens the shoulder 221 'on the head piece.
  • the plug has a housing for a helical spring 266 which surrounds the cannula 220 and which is located between the plug 230 and the clamping ring 262.
  • the spring 266 has the function of ensuring the tightening and expansion of the part conical 250 'of the sheath.
  • This embodiment has the advantage of allowing the differential expansions between the cannula and the sheath to be made up for when injecting cold water.
  • the relative movement of the cannula relative to the sheath is done freely at the level of the head pieces and not under frictional stress in the tube 10a.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Monitoring And Testing Of Nuclear Reactors (AREA)
  • External Artificial Organs (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Detergent Compositions (AREA)

Claims (6)

1. Einrichtung zur Injektion eines Fluids in ein vertikales Rohr (10), welches eine in dem genannten Rohr angeordnete Kanüle (220) aufweist, die in Fluidinjektionsrichtung einen Durchlaß mit in bezug auf den Durchmesser des Rohres verengtem Querschnitt (238) aufweist, dem an seinem unteren Abschnitt eine Aufweitung (222) folgt, wobei die Kanüle (220) sich an ihrem unteren Abschnitt befindende Mittel zur Zentrierung und Verschiebungssicherung in bezug auf das Rohr (10) aufweist, dadurch gekennzeichnet, daß eine koaxial in dem Rohr (10) befestigte Hülse (220') die Kanüle umgibt und daß die Mittel zur Zentrierung und Verschiebungssicherung der Kanüle an dem Rohr (10) von einem zylindrischen Zentrierungsabschnitt (226') zur Zentrierung der Hülse in dem Rohr, wenigstens einem Spalt (224') und einem inneren Konus (250'), die am unteren Abschnitt in der Hülse (220') ausgebildet sind, sowie von einem an dem unteren Abschnitt der Kanüle (220) ausgebildeten äußeren Konus (250) gebildet sind, wobei der innere Konus (250') und der äußere Konus (250) zusammenarbeiten können und Mittel vorgesehen sind, um den äußeren Konus (250) elastisch auf den inneren Konus (250') zu drücken.
2. Einrichtung nach Anspruch 1, dadurch gekennzeichnet, daß der Querschnitt des Fluiddurchlasses (238) mit verengtem Querschnitt in der Kanüle (220) derart ist, daß die Geschwindigkeit des genannten Fluids größer als 0,7 m/sec. ist.
3. Einrichtung nach Anspruch 1 oder 2, dadurch gekennzeichnet, daß die Mittel, um den äußeren Konus (250) auf den inneren Konus (250') zu drücken, von Anschlagmitteln, die sich am oberen Ende der Kanüle (220) befinden, und einer Feder (266) gebildet sind, die zwischen die genannten Anschlagmittel und einen Stopfen (230) zwischengefügt ist, der auf ein Kopfteil (228) geschraubt ist.
4. Einrichtung nach Anspruch 3, dadurch gekennzeichnet, daß die genannten Anschlagmittel von einem Spannring (262), der auf einen Gewindeabschnitt (260) der Kanüle (220) geschraubt ist, und einer Gegenmutter (264) gebildet sind.
5. Dampferzeuger mit einer Injektionseinrichtung nach irgendeinem der Ansprüche 1 bis 3.
6. Dampferzeuger mit einem Mantel (4), einer Rohrplatte (8), die sich im Inneren des Mantels (4) befindet und den Mantel in einen Wasserkasten (7) und eine Wärmetauscherzone unterteilt, einem Einlaß (4a) und einem Auslaß (4b) für ein Primärfluid, die sich in der Wärmetauscherzone des Mantels befinden, einem Einlaß (14) und einem Auslaß (18) für ein Sekundärfluid, die sich in dem Wasserkasten befinden, einer Vielzahl von vertikalen Rohren (10), die ein Einlaßende und ein Auslaßende für das Sekundärfluid aufweisen, wobei die genannten Einlaß- und Auslaßenden an der Rohrplatte befestigt sind und jedes Rohr (10) einen geradlinigen Abschnitt (10a) auf der Seite seines Einlaßendes aufweist, einer Injektionseinrichtung für das Sekundärfluid in ein Rohr (10), welches eine Kanüle (220) aufweist, die im Inneren des Einlaßendes eines Rohres (10) angeordnet ist und einen Durchlaßquerschnitt, der in bezug auf den Rohrdurchmesser verengt ist, für das Sekundärfluid aufweist, der in Strömungsrichtung des Sekundärfluids gefolgt ist von einer Erweiterung (222) an ihrem unteren Abschnitt, dadurch gekennzeichnet, daß eine Hülse (220') koaxial zwischen der genannten Kanüle (220) und dem geradlinigen Abschnitt (10a) des Rohres (10) angeordnet ist, Mittel zur Zentrierung der Kanüle (220) in bezug auf den geradlinigen Abschnitt (10a) des Rohres (10) vorgesehen sind und daß die Mittel zur Zentrierung und Verschiebungssicherung der Kanüle bei dem Rohr (10) von einem zylindrischen Zentrierungsabschnitt (226') zur Zentrierung der Hülse in dem Rohr, wenigstens einem Schlitz (224') und einem inneren Konus (250'), die in der Hülse (220') an ihrem unteren Abschnitt ausgebildet sind, sowie von einem äußeren Konus (250) gebildet sind, der an dem unteren Abschnitt der Kanüle (220) ausgebildet ist, wobei der innere Konus (250') und der äußere Konus (250) zusammenarbeiten können und Mittel vorgesehen sind, um den äußeren Konus (250) elastisch auf den inneren Konus (250') zu drücken.
EP85401000A 1984-05-29 1985-05-21 Flüssigkeitsinjektionseinrichtung in einem Rohr und Dampferzeuger mit solcher Einrichtung Expired EP0165846B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8408414A FR2565322B1 (fr) 1984-05-29 1984-05-29 Dispositif d'injection d'un liquide dans un tube et generateur de vapeur comportant ce dispositif
FR8408414 1984-05-29

Publications (2)

Publication Number Publication Date
EP0165846A1 EP0165846A1 (de) 1985-12-27
EP0165846B1 true EP0165846B1 (de) 1988-09-28

Family

ID=9304496

Family Applications (1)

Application Number Title Priority Date Filing Date
EP85401000A Expired EP0165846B1 (de) 1984-05-29 1985-05-21 Flüssigkeitsinjektionseinrichtung in einem Rohr und Dampferzeuger mit solcher Einrichtung

Country Status (5)

Country Link
US (1) US4721067A (de)
EP (1) EP0165846B1 (de)
JP (1) JPS60256702A (de)
DE (1) DE3565310D1 (de)
FR (1) FR2565322B1 (de)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2694071B1 (fr) * 1992-07-22 1994-10-14 Framatome Sa Procédé et dispositif de réglage d'un débit d'eau d'alimentation dans un tube d'un générateur de vapeur.
WO2012034050A2 (en) * 2010-09-09 2012-03-15 Certek Heat Machine Usa, Llc Dugout heating system

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE554160C (de) * 1932-07-02 L & C Steinmueller Wasserrohrkessel
US3357409A (en) * 1964-10-07 1967-12-12 Atomic Energy Authority Uk Vertical tube module once-through steam generator
AT278863B (de) * 1968-01-15 1970-02-10 Waagner Biro Ag Verfahren und Einrichtung zur Vergleichmäßigung des Wärmeüberganges
US3596638A (en) * 1968-10-15 1971-08-03 Siemens Ag Forced-flow steam generator to be heated by pressurized coolant of a nuclear reactor
US3707186A (en) * 1971-01-18 1972-12-26 Foster Wheeler Corp Cooling tube ferrule
JPS5723761Y2 (de) * 1972-10-16 1982-05-24
US3992172A (en) * 1975-03-06 1976-11-16 Foster Wheeler Energy Corporation Separator arrangement for start-up system
US4285396A (en) * 1979-01-25 1981-08-25 Wachter Associates, Inc. Steam generator tube support system
US4191246A (en) * 1979-03-05 1980-03-04 Combustion Engineering, Inc. Device to reduce local heat flux through a heat exchanger tube
CH640631A5 (de) * 1979-06-20 1984-01-13 Bbc Brown Boveri & Cie Waermeaustauscher.
DE3027510A1 (de) * 1980-07-19 1982-02-18 Hochtemperatur Reaktorbau Gmbh Gewoelbter deckel zum verschliessen einer vertikalen ausnehmung in einem druckgefaess
US4579087A (en) * 1983-12-21 1986-04-01 Westinghouse Electric Corp. Corrosion resistant steam generator and method of making same

Also Published As

Publication number Publication date
FR2565322A1 (fr) 1985-12-06
EP0165846A1 (de) 1985-12-27
US4721067A (en) 1988-01-26
FR2565322B1 (fr) 1986-08-01
DE3565310D1 (en) 1988-11-03
JPS60256702A (ja) 1985-12-18

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