EP0271739B1 - Process for the repair or protection of one extremity of a metallic heat exchanger tube, and sleeve for carrying it out - Google Patents
Process for the repair or protection of one extremity of a metallic heat exchanger tube, and sleeve for carrying it out Download PDFInfo
- Publication number
- EP0271739B1 EP0271739B1 EP87117143A EP87117143A EP0271739B1 EP 0271739 B1 EP0271739 B1 EP 0271739B1 EP 87117143 A EP87117143 A EP 87117143A EP 87117143 A EP87117143 A EP 87117143A EP 0271739 B1 EP0271739 B1 EP 0271739B1
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- EP
- European Patent Office
- Prior art keywords
- tube
- sleeve
- area
- corrosion
- submitted
- 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 - Lifetime
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F11/00—Arrangements for sealing leaky tubes and conduits
- F28F11/02—Arrangements for sealing leaky tubes and conduits using obturating elements, e.g. washers, inserted and operated independently of each other
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- 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
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T29/00—Metal working
- Y10T29/49—Method of mechanical manufacture
- Y10T29/4935—Heat exchanger or boiler making
- Y10T29/49352—Repairing, converting, servicing or salvaging
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- 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
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T29/00—Metal working
- Y10T29/49—Method of mechanical manufacture
- Y10T29/49718—Repairing
- Y10T29/49732—Repairing by attaching repair preform, e.g., remaking, restoring, or patching
- Y10T29/49742—Metallurgically attaching preform
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- 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
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T29/00—Metal working
- Y10T29/49—Method of mechanical manufacture
- Y10T29/49718—Repairing
- Y10T29/49748—Repairing by shaping, e.g., bending, extruding, turning, etc.
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- 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
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T29/00—Metal working
- Y10T29/49—Method of mechanical manufacture
- Y10T29/49826—Assembling or joining
- Y10T29/49908—Joining by deforming
- Y10T29/49909—Securing cup or tube between axially extending concentric annuli
- Y10T29/49911—Securing cup or tube between axially extending concentric annuli by expanding inner annulus
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- 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
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T29/00—Metal working
- Y10T29/49—Method of mechanical manufacture
- Y10T29/49826—Assembling or joining
- Y10T29/49908—Joining by deforming
- Y10T29/49938—Radially expanding part in cavity, aperture, or hollow body
- Y10T29/4994—Radially expanding internal tube
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- 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
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/12—All metal or with adjacent metals
- Y10T428/12347—Plural layers discontinuously bonded [e.g., spot-weld, mechanical fastener, etc.]
Definitions
- the present invention relates to a method for repairing or protecting a damaged or corrosion-prone area of an end of a metal exchanger tube in the vicinity of the internal face of its tube plate, in which the inside is inserted tube a metal sleeve with an external diameter less than the internal diameter of the tube, over a sufficient length from the external face of the tube plate to penetrate the tube beyond the damaged or prone to corrosion area, localized expansion is carried out from the end of the sleeve located on the side of the external face of the tube plate on the tube, this end of the sleeve is locally welded to the corresponding end of the tube, the end of the sleeve is docked in the tube beyond the damaged or corrosion-prone area and locally welds this end of the sleeve to the inside of the tube with partial penetration into it. It also extends to a mason usable in this process.
- one of the fluids for example the heating fluid
- circulates inside the tubes and the other, for example the heated fluid, to the outside of the tubes.
- Document EP A 0 181 250 describes a method for repairing a damaged or corrosion-prone area at the end of a metal tube of a steam generator in the vicinity of the internal face of its tube plate, in which the inside the tube a metal jacket with an external diameter slightly smaller than the internal diameter of the tube over a length sufficient to penetrate the tube beyond the damaged area.
- An expansion of the part of the liner close to the external face of the tube plate is carried out in the tube, then the corresponding edges of the sleeve and of the tube are welded together.
- the end of the sleeve is expanded diametrically beyond the area damaged by swelling and the expanded part of the sleeve is brazed with the tube.
- Document EP-A 0 121 137 has proposed a similar method, in which, after having accosted the sleeve against the tube beyond the damaged zone of the tube, the sleeve was subjected to an upward or downward translation to ensure better contact between them, then performed a weld in the expanded area between the sleeve and the tube.
- This process had the same defect as the previous one with regard to the appearance of thermal stresses between tube and sleeve at the weld between their edges and did not make it possible to precisely determine the translation of the sleeve necessary to obtain a good seal of the area of the expanded sleeve beyond the damaged area of the tube.
- the object of the present invention is to provide a method of repairing or protecting a damaged or subject to corrosion area of a tube end, which avoids any danger of subsequent corrosion of the tube, in particular by creating excessive residual stresses in that -this, while constituting a mechanically robust protection and an absolute seal.
- the method according to the invention is characterized in that the localized welding is carried out inside the expanded zone set back from the edge of the sleeve, with partial penetration of the weld into the tube, and in that then performs an expansion of the end region of the sleeve against the tube in an area located inside the tube plate above the localized weld.
- the invention further extends to a sleeve for carrying out the method of the invention, with an external diameter slightly less than the internal diameter of the tube, and with a length greater than that of the damaged area or subject to corrosion, characterized in that it comprises either in the vicinity of one of its ends an external metallic coating of small thickness which is a good conductor of heat and which is not very oxidizable, or, at least at one of its ends, an area provided with fines longitudinal external grooves, or both.
- the tube 1 is fixed to the tubular plate 2, in the usual way, by swaging, and its lower end is welded to the external face of this plate, as represented by the weld bead 3.
- the repair is carried out using an internal sleeve 5, with an external diameter slightly smaller than the internal diameter of the tube, which covers the partially corroded zone of the tube.
- This sleeve 5 is tightly connected to the tube in the two zones 6, inside the tube plate, and 7, beyond the latter and the corroded zone.
- the sleeve is first expanded in the tube in a localized manner in this zone. This expansion can take place under inert gas or with inert gas blowing.
- the welding is carried out back from the edge of the sleeve by the automatic arc arc process using an inert gas using a device for internal welding of tubes (this position allowing greater flexibility in the adjustment in altitude welding torch).
- the preliminary expansion allows the heat to be concentrated in the area to be welded, which facilitates the penetration of the weld, the removal of the metal after welding and the evacuation of the gas trapped between the tube and the sleeve.
- the weld bead must have good penetration into the thickness of the tube (from 20% to 75% thereof), but without crossing it.
- the sleeve can be provided in the region provided for the weld bead and on either side of it with a thin deposit of a metal which is not very oxidizable and which is a good conductor of heat. , such as le.chrome, obtained for example by metallization (deposit 14 in fig. 3). It is also possible, in order to further facilitate the evacuation of the air retained in the gap between the tube and the sleeve, to provide the lower end of the sleeve up to the level of the weld bead with fine longitudinal grooves. , for example four grooves at 90 ° (grooves 15 and fig. 4). The air can be evacuated either by blowing inert gas, or by vacuum, if the assembly allows.
- the upper weld is then produced after the sleeve has come into contact with the tube by controlled deformation of the diameter, by controlling the expansion of the sleeve by the number of spindle turns of a dudgeon.
- This ensures good repeatability of obtaining good contact between the tube and the sleeve, a necessary condition for ensuring good bond welding by limiting the stresses induced in the tube.
- This upper welding can also be carried out behind the edge of the sleeve, for example at 20 or 30 mm from this edge (weld bead 9 in FIG. 1). It is also possible to ensure complete fusion welding of the edge of the sleeve (weld bead 9A in FIG. 2).
- the shape of this connection allows the control of the zone 13 thermally affected by the welding and located above the welding.
- This type of weld bead is obtained by adjusting the position and the inclination of the welding electrode, that is to say by appropriate preparation of the end of the sleeve by machining.
- the welding operations by the arc process under inert gas with tungsten electrode can optionally be substituted for laser beam or electron beam welds.
- the quality of the welds can be controlled by non-destructive means such as endoscopic examination, penetrant testing, eddy currents and ultrasound.
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Butt Welding And Welding Of Specific Article (AREA)
- Arc Welding In General (AREA)
Abstract
Description
La présente invention concerne un procédé de réparation ou de protection d'une zone endommagée ou sujette à corrosion d'une extrémité de tube métallique d'échangeur au voisinage de la face interne de sa plaque tubulaire, dans lequel on introduit à l'intérieur du tube un manchon métallique de diamètre externe inférieur au diamètre interne du tube, sur une longueur suffisante à partir de la face externe de la plaque tubulaire pour pénétrer dans le tube au-delà de la zone endommagée ou sujette à corrosion, on effectue un dudgeonnage localisé de l'extrémité du manchon située du côté de la face externe de la plaque tubulaire sur le tube, on soude localement cette extrémité du manchon sur l'extrémité correspondante du tube, on accoste dans le tube l'extrémité du manchon au-delà de la zone endommagée ou sujette à corrosion et soude localement cette extrémité du manchon sur l'intérieur du tube avec pénétration partielle dans celui-ci. Elle s'étend en outre à un ma- chon utilisable dans ce procédé.The present invention relates to a method for repairing or protecting a damaged or corrosion-prone area of an end of a metal exchanger tube in the vicinity of the internal face of its tube plate, in which the inside is inserted tube a metal sleeve with an external diameter less than the internal diameter of the tube, over a sufficient length from the external face of the tube plate to penetrate the tube beyond the damaged or prone to corrosion area, localized expansion is carried out from the end of the sleeve located on the side of the external face of the tube plate on the tube, this end of the sleeve is locally welded to the corresponding end of the tube, the end of the sleeve is docked in the tube beyond the damaged or corrosion-prone area and locally welds this end of the sleeve to the inside of the tube with partial penetration into it. It also extends to a mason usable in this process.
Dans les échangeurs de chaleur du type à faisceau de tubes fixés sur des plaques tubulaires épaisses, l'un des fluides, par exemple le fluide chauffant, circule à l'intérieur des tubes, et l'autre, par exemple le fluide chauffé, à l'extérieur des tubes.In heat exchangers of the tube bundle type fixed on thick tubular plates, one of the fluids, for example the heating fluid, circulates inside the tubes, and the other, for example the heated fluid, to the outside of the tubes.
Lorsqu'à la suite d'une corrosion un défaut traverse la paroi d'un ou de plusieurs tubes, provoquant la fuite d'un débit, même relativement faible, de l'un des fluides dans l'autre, il s'ensuit divers inconvénients:
- - perte d'efficacité de l'échangeur. donc du rendement de l'installation,
- - risque d'aggravation du défaut, de rupture totale du tube et d'endommagement des tubes voisins par effet de fouet,
- - dans le cas d'un échangeur de centrale nucléaire, notamment des générateurs de vapeur des chaudières de centrales nucléaires à eau sous pression, fuite possible de fluide radioactif vers le fluide non radioactif, et de contamination du circuit de ce dernier.
- - loss of efficiency of the exchanger. therefore the performance of the installation,
- - risk of aggravation of the defect, total rupture of the tube and damage to neighboring tubes by whipping effect,
- - in the case of a nuclear power plant exchanger, in particular steam generators in boilers of pressurized water nuclear power plants, possible leakage of radioactive fluid towards the non-radioactive fluid, and contamination of the latter's circuit.
Lorsqu'une fuite intervient dans la paroi d'un tube, on a déjà proposé d'éliminer celui-ci par bouchage à l'aide de bouchons mis en place aux deux extrémités du tube dans la ou les plaques tubulaires. Ceci ne peut toutefois se faire que pour un nombre limité de tubes, pour ne pas réduire de façon importante le débit de fluide traité par l'échangeur.When a leak occurs in the wall of a tube, it has already been proposed to eliminate the latter by plugging using plugs placed at both ends of the tube in the tube plate (s). This can however only be done for a limited number of tubes, in order not to significantly reduce the flow of fluid treated by the exchanger.
On a aussi proposé d'arrêter la fuite à l'aide d'un manchon interne mis en place, soit par dudgeonnage mécanique, soit par dudgeonnage hydraulique, soit par expansion à l'aide d'une bague en élastomère, soit par explosion, soit par brasage.It has also been proposed to stop the leak using an internal sleeve put in place, either by mechanical expansion, or by hydraulic expansion, or by expansion using an elastomer ring, or by explosion, either by soldering.
De tels procédés ne donnent pas complètement satisfaction, car la fixation du manchon dans le tube par les procédés de dudgeonnage mécanique ou hydraulique, ou par expansion par une bague en élastomère, ou par explosion, induit dans le tube des contraintes, source de danger de corrosion, qui ne peuvent être éliminées sous peine de dédudgeonna- ge.Such methods are not completely satisfactory, since the fixing of the sleeve in the tube by mechanical or hydraulic expansion methods, or by expansion by an elastomer ring, or by explosion, induced in the tube stresses, source of danger of corrosion, which cannot be eliminated under penalty of dedudgeonnage.
Le document EP A 0 181 250 décrit un procédé de réparation d'une zone endommagée ou sujette à corrosion d'une extrémité de tube métallique de générateur de vapeur au voisinage de la face interne de sa plaque tubulaire, dans lequel on introduit à l'intérieur du tube une chemise métallique de diamètre externe légèrement inférieur au diamètre interne du tube sur une longueur suffisante pour pénétrer dans le tube au-delà de la zone endommagée. On effectue un dudgeonnage de la partie de la chemise proche de la face externe de la plaque tubulaire dans le tube, puis soude entre eux les bords correspondants du manchon et du tube. On expanse diamétralement l'extrémité du manchon au-delà de la zone endommagée par dudgeonnage et on brase la partie expansée du manchon avec le tube. Un tel procédé crée des contraintes thermiques à l'endroit de la soudure entre les bords du manchon et du tube, et ne permet pas de protéger la zone de la soudure entre tube et manchon à l'intérieur de la plaque tubulaire contre les infiltrations du fluide circulant autour des tubes, et entraîne donc des dangers de corrosion de 3 cette soudure. Par ailleurs, le brasage entre tube et manchon au-delà de la zone endommagée du tube, soumis en service à des températures élevées et parfois à des variations de température importantes, perd à la longue de son étanchéité.Document EP A 0 181 250 describes a method for repairing a damaged or corrosion-prone area at the end of a metal tube of a steam generator in the vicinity of the internal face of its tube plate, in which the inside the tube a metal jacket with an external diameter slightly smaller than the internal diameter of the tube over a length sufficient to penetrate the tube beyond the damaged area. An expansion of the part of the liner close to the external face of the tube plate is carried out in the tube, then the corresponding edges of the sleeve and of the tube are welded together. The end of the sleeve is expanded diametrically beyond the area damaged by swelling and the expanded part of the sleeve is brazed with the tube. Such a process creates thermal stresses at the location of the weld between the edges of the sleeve and of the tube, and does not make it possible to protect the area of the weld between tube and sleeve inside the tube plate against infiltration of the fluid circulating around the tubes, and therefore leads to the danger of corrosion of this weld. Furthermore, the brazing between tube and sleeve beyond the damaged zone of the tube, subjected in service to high temperatures and sometimes to significant temperature variations, loses its sealing in the long run.
On a proposé dans le document EP-A 0 121 137 un procédé analogue, dans lequel, après avoir accosté le manchon contre le tube au-delà de la zone endommagée du tube, on soumettait le manchon à une translation vers le haut ou le bas pour assurer un meilleur contact entre eux, puis effectuait une soudure dans la zone expansée entre le manchon et le tube. Ce procédé présentait le même défaut que le précédent en ce qui concerne l'apparition de contraintes thermiques entre tube et manchon au niveau de la soudure entre leurs bords et ne permettait pas de déterminer avec précision la translation du manchon nécessaire pour obtenir une bonne étanchéité de la zone du manchon expansée au-delà de la zone endommagée du tube.Document EP-A 0 121 137 has proposed a similar method, in which, after having accosted the sleeve against the tube beyond the damaged zone of the tube, the sleeve was subjected to an upward or downward translation to ensure better contact between them, then performed a weld in the expanded area between the sleeve and the tube. This process had the same defect as the previous one with regard to the appearance of thermal stresses between tube and sleeve at the weld between their edges and did not make it possible to precisely determine the translation of the sleeve necessary to obtain a good seal of the area of the expanded sleeve beyond the damaged area of the tube.
La présente invention a pour but de procurer un procédé de réparation ou de protection d'une zone endommagée ou sujette à corrosion d'une extrémité de tube, qui évite tout danger de corrosion ultérieure du tube, notamment par création de contraintes résiduelles excessives dans celui-ci, tout en constituant une protection mécaniquement robuste et d'une étanchéité absolue.The object of the present invention is to provide a method of repairing or protecting a damaged or subject to corrosion area of a tube end, which avoids any danger of subsequent corrosion of the tube, in particular by creating excessive residual stresses in that -this, while constituting a mechanically robust protection and an absolute seal.
Le procédé selon l'invention est caractérisé en ce que l'on effectue le soudage localisé à l'intérieur de la zone dudgeonnée en retrait du bord du manchon, avec pénétration partielle de la soudure dans le tube, et en ce que l'on effectue ensuite un dudgeonnage de la zone d'extrémité du manchon contre le tube dans une zone située à l'intérieur de la plaque tubulaire au-dessus de la soudure localisée.The method according to the invention is characterized in that the localized welding is carried out inside the expanded zone set back from the edge of the sleeve, with partial penetration of the weld into the tube, and in that then performs an expansion of the end region of the sleeve against the tube in an area located inside the tube plate above the localized weld.
Il répond de préférence à au moins l'une des caractéristiques suivantes:
- - Préalablement à l'introduction du manchon dans le tube, on perce dans le tube un ou plusieurs trous de faible diamètre, traversant sa paroi complètement ou incomplètement, légèrement au-delà de la face interne de la plaque tubulaire.
- - On effectue un dudgeonnage localisé de l'extrémité du manchon du côté de la face externe de la plaque tubulaire sous gaz inerte ou avec soufflage de gaz inerte.
- - Préalablement à l'introduction du manchon dans le tube, on munit l'extrémité de celui-ci destinée à être dudgeonnée dans le tube du côté de la face externe de la plaque tubulaire d'un revêtement métallique de faible épaisseur, bon conducteur de la chaleur et peu oxydable.
- - Préalablement à l'introduction du manchon dans le tube, on munit l'extrémité de celui-ci destinée à être dudgeonnée dans le tube du côté de la face externe de la plaque tubulaire d'une série de rainures longitudinales, et avant d'effectuer le soudage on chasse l'air présent dans l'interstice entre le tube et le manchon par soufflage de gaz inerte dans ces rainures ou par mise sous vide de celles-ci.
- - On munit aussi l'autre extrémité du manchon d'une série de rainures longitudinales, et avant d'effectuer le soudage près de cette autre extrémité on chasse l'air présent dans l'interstice entre le tube et le manchon par soufflage de gaz inerte dans les rainures ou par mise sous vide.
- - Après avoir effectué la soudure du manchon sur la zone d'extrémité du tube du côté de la face externe de la plaque tubulaire, on effectue plusieurs passes de dudgeonnage du manchon dans le tube au-delà de cette soudure.
- - On effectue les soudages du manchon sur le tube au-delà de la zone endommagée ou sujette à corrosion en retrait de l'extrémité du manchon.
- - On effectue l'accostage de l'extrémité du manchon dans le tube au-delà de la zone endommagée ou sujette à corrosion par déformation contrôlée du diamètre.
- - On effectue le soudage du manchon sur le tube au-delà de la zone endommagée ou sujette à corrosion sur le bord lui-même du manchon.
- - On soumet la soudure de l'extrémité dudgeonnée du manchon sur l'intérieur du tube au-delà de la zone endommagée ou sujette à corrosion à un traitement de détensionnement à l'aide d'un inducteur interne.
- - On soumet la zone du manchon au-delà de celle dudgeonnée dans le tube à l'intérieur de la plaque tubulaire à un traitement de détensionnement par un dudgeonnage léger.
- - Prior to the introduction of the sleeve into the tube, one or more small diameter holes are drilled in the tube, crossing its wall completely or incompletely, slightly beyond the internal face of the tube plate.
- - We carry out a local expansion of the end of the sleeve on the side of the external face of the tube plate under inert gas or with inert gas blowing.
- - Prior to the introduction of the sleeve into the tube, the end of the latter intended to be expanded in the tube on the side of the external face of the tubular plate is provided with a thin metal coating, good conductor of heat and not very oxidizable.
- - Prior to the introduction of the sleeve into the tube, the end of the latter intended to be expanded in the tube on the side of the external face of the tube plate is provided with a series of longitudinal grooves, and before carry out the welding, the air present in the gap between the tube and the sleeve is expelled by blowing inert gas into these grooves or by evacuating them.
- - The other end of the sleeve is also provided with a series of longitudinal grooves, and before welding near this other end, the air present in the gap between the tube and the sleeve is expelled by gas blowing inert in the grooves or by vacuum.
- - After carrying out the welding of the sleeve on the end zone of the tube on the side of the external face of the tube plate, several passes of expansion of the sleeve in the tube are carried out beyond this welding.
- - The welding of the sleeve is carried out on the tube beyond the damaged area or subject to corrosion set back from the end of the sleeve.
- - The end of the sleeve is docked in the tube beyond the damaged area or subject to corrosion by controlled deformation of the diameter.
- - The sleeve is welded to the tube beyond the damaged or subject to corrosion area on the edge itself of the sleeve.
- - The weld on the end of the sleeve is subjected to the inside of the tube beyond the damaged area or subject to corrosion to a stress relieving treatment using an internal inductor.
- - The area of the sleeve beyond that in the tube in the tube inside the tube plate is subjected to a stress relieving treatment by light expansion.
L'invention s'étend en outre à un manchon pour la mise en oeuvre du procédé de l'invention, de diamètre externe légèrement inférieur au diamètre interne du tube, et de longueur supérieure à celle de la zone endommagée ou sujette à corrosion, caractérisé en ce qu'il comporte soit au voisinage de l'une de ses extrémités un revêtement métallique externe de faible épaisseur bon conducteur de la chaleur et peu oxydable, soit à partie d'au moins l'une de ses extrémités une zone munie de fines rainures externes longitudinales, soit les deux.The invention further extends to a sleeve for carrying out the method of the invention, with an external diameter slightly less than the internal diameter of the tube, and with a length greater than that of the damaged area or subject to corrosion, characterized in that it comprises either in the vicinity of one of its ends an external metallic coating of small thickness which is a good conductor of heat and which is not very oxidizable, or, at least at one of its ends, an area provided with fines longitudinal external grooves, or both.
Il est décrit ci-après, à titre d'exemples et en référence aux figures du dessin annexé, les extrémités voisines de la plaque tubulaire de tubes d'échangeur de chaleur entre eau primaire radioactive réchauffée par passage dans le coeur d'un réacteur nucléaire, et eau secondaire à réchauffer par échange indirect de chaleur avec l'eau primaire, réparés par le procédé de l'invention.
- La figure 1 représente en élévation avec coupe diamétrale partielle l'extrémité d'un tube au voisinage de la plaque tubulaire, munie d'un manchon interne de réparation dudgeonné et soudé sur le tube.
- La figure 2 représente en élévation avec coupe diamétrale partielle une variante de réparation dans laquelle le manchon est soudé sur le tube le long de son bord supérieur.
- La figure 3 représente une variante de manchon de réparation, munie près de son bord inférieur d'un mince dépôt d'un métal peu oxydable et bon conducteur de la chaleur.
- La figure 4 représente une variante de manchon de réparation, munie près de son bord inférieur de rainures permettant de chasser l'air lors de son soudage au tube.
- Figure 1 shows in elevation with partial diametral section the end of a tube in the vicinity of the tube plate, provided with an internal repair sleeve expanded and welded to the tube.
- Figure 2 shows in elevation with partial diametral section a repair variant in which the sleeve is welded to the tube along its upper edge.
- FIG. 3 represents a variant of the repair sleeve, provided near its lower edge with a thin deposit of a metal which is not very oxidizable and which is a good conductor of heat.
- FIG. 4 represents a variant of repair sleeve, provided near its lower edge with grooves making it possible to expel the air during its welding to the tube.
Dans la figure 1, le tube 1 est fixé à la plaque tubulaire 2, de la manière habituelle, par dudgeonnage, et son extrémité inférieure est soudée à la face externe de cette plaque, comme représenté par le cordon de soudure 3.In FIG. 1, the tube 1 is fixed to the
La zone de fin de dudgeonnage du tube, au voisinage de la face interne de la plaque tubulaire, a été soumise à une corrosion sous contrainte qui l'a endommagée, comme représenté en 4.The end of the expansion of the tube, in the vicinity of the internal face of the tube plate, was subjected to stress corrosion which damaged it, as shown in 4.
La réparation est effectuée à l'aide d'un manchon interne 5, de diamètre externe un peu inférieur au diamètre interne du tube, qui recouvre la zone du tube partiellement corrodée.The repair is carried out using an
Ce manchon 5 est lié de façon étanche au tube dans les deux zones 6, à l'intérieur de la plaque tubulaire, et 7, au-delà de celle-ci et de la zone corrodée.This
Pour réaliser la liaison inférieure dans la zone 6 à l'intérieur de la plaque tubulaire, le manchon est d'abord dudgeonné dans le tube de façon localisée dans cette zone. Ce dudgeonnage peut avoir lieu sous gaz inerte ou avec soufflage de gaz inerte.To make the lower connection in zone 6 inside the tube plate, the sleeve is first expanded in the tube in a localized manner in this zone. This expansion can take place under inert gas or with inert gas blowing.
Puis l'on effectue le soudage en retrait du bord du manchon par le procédé automatique à l'arc sous gaz inerte à l'aide d'un dispositif pour soudage interne de tubes (cette position autorisant une plus grand souplesse dans le réglage en altitude de la torche de soudage). Le dudgeonnage préliminaire permet de concentrer la chaleur dans la zone à souder, ce qui facilite la pénétration de la soudure, les retraits du métal après soudage et l'évacuation du gaz emprisonné entre le tube et le manchon. Le cordon de soudure doit présenter une bonne pénétration dans l'épaisseur du tube (de 20% à 75% de celle-ci), mais sans la traverser.Then the welding is carried out back from the edge of the sleeve by the automatic arc arc process using an inert gas using a device for internal welding of tubes (this position allowing greater flexibility in the adjustment in altitude welding torch). The preliminary expansion allows the heat to be concentrated in the area to be welded, which facilitates the penetration of the weld, the removal of the metal after welding and the evacuation of the gas trapped between the tube and the sleeve. The weld bead must have good penetration into the thickness of the tube (from 20% to 75% thereof), but without crossing it.
Pour faciliter l'opération de soudage, le manchon peut être muni dans la région prévue pour le cordon de soudure et de part et d'autre de celle-ci d'un mince dépôt d'un métal peu oxydable et bon conducteur de la chaleur, tel que le.chrome, obtenu par exmple par métallisation (dépôt 14 de la fig.3). On peut aussi, afin de faciliter encore plus l'évacuation de l'air retenu dans l'interstice entre le tube et le manchon, munir l'extrémité inférieure du manchon jusqu'au-delà du niveau du cordon de soudure de fines rainures longitudinales, par exemple quatre rainures à 90° (rainures 15 et de la fig.4). L'évacuation de l'air peut s'effectuer soit par soufflage de gaz inerte, soit par mise sous vide, si l'assemblage le permet.To facilitate the welding operation, the sleeve can be provided in the region provided for the weld bead and on either side of it with a thin deposit of a metal which is not very oxidizable and which is a good conductor of heat. , such as le.chrome, obtained for example by metallization (deposit 14 in fig. 3). It is also possible, in order to further facilitate the evacuation of the air retained in the gap between the tube and the sleeve, to provide the lower end of the sleeve up to the level of the weld bead with fine longitudinal grooves. , for example four grooves at 90 ° (
Après réalisation de la soudure inférieure, on soumet la zone 6 au-dessus de celle-ci à plusieurs passes de dudgeonnage, en assurant ainsi une barrière d'étanchéité, soustrayant la zone affectée par la soudure à l'action corrosive de l'eau circulant autour des tubes. Un traitement thermique de suppression des tensions dans ce cordon de soudure, susceptible d'avoir un effet défavorable en raison de la présence de la plaque tubulaire, n'est plus nécessaire.After completion of the lower weld, the area 6 above it is subjected to several expansion steps, thus ensuring a sealing barrier, subtracting the area affected by the weld from the corrosive action of water. circulating around the tubes. A heat treatment to remove the tensions in this weld bead, which may have an unfavorable effect due to the presence of the tube plate, is no longer necessary.
On réalise ensuite la soudure supérieure après accostage du manchon dans le tube par déformation contrôlée du diamètre, en pilotant l'expansion du manchon par le nombre de tours de broche d'un dudgeon. On assure ainsi une bonne répétitivité de l'obtention d'un bon contact entre tube et manchon, condition nécessaire pour assurer une bonne soudure de liaison en limitant les contraintes induites dans le tube. Cette soudure supérieure peut être effectuée également en retrait du bord du manchon, par exemple à 20 ou 30 mm de ce bord (cordon de soudure 9 de la figure 1). On peut aussi assurer la soudure par fusion complète du bord du manchon (cordon de soudure 9A de la fig.2). La forme de cette liaison permet le contrôle de la zone 13 affectée thermiquement par le soudage et située au-dessus de la soudure.The upper weld is then produced after the sleeve has come into contact with the tube by controlled deformation of the diameter, by controlling the expansion of the sleeve by the number of spindle turns of a dudgeon. This ensures good repeatability of obtaining good contact between the tube and the sleeve, a necessary condition for ensuring good bond welding by limiting the stresses induced in the tube. This upper welding can also be carried out behind the edge of the sleeve, for example at 20 or 30 mm from this edge (weld bead 9 in FIG. 1). It is also possible to ensure complete fusion welding of the edge of the sleeve (
Ce type de cordon de soudure est obtenu par réglage de la position et de l'inclinaison de l'électrode de soudage, soit par une préparation appropriée de l'extrémité du manchon par usinage.This type of weld bead is obtained by adjusting the position and the inclination of the welding electrode, that is to say by appropriate preparation of the end of the sleeve by machining.
Quelle que soit la position de la soudure supérieure du manchon, on peut assurer la suppression des tensions dans celle-ci à l'aide d'un traitement thermique local par inducteur interne.Whatever the position of the upper weld of the sleeve, it is possible to ensure the removal of the tensions therein by means of a local heat treatment by internal inductor.
Afin d'éviter une montée en pression éventuelle dans l'espace 11 compris entre le tube et le manchon par accumulation à travers une fuite de résidus divers, de gaz ou d'eau, il est possible de percer un ou plusieurs trous tels que 12 dans le tube, préalablement à la mise en place du manchon. Ces trous peuvent traverser de part en part la paroi du tube, comme représenté. On peut aussi laisser une faible épaisseur résiduelle de métal du tube, celle-ci servant alors de membrane de sécurité en cas d'une montée en pression dans l'espace 11. Ce ou ces trous peuvent également contribuer à faciliter la réalisation de la liaison supérieure entre le tube et le manchon, notamment lors de l'opération de soudage, où le gaz emprisonné pourrait gêner la fermeture du bain de soudure.In order to avoid a possible increase in pressure in the space 11 between the tube and the sleeve by accumulation through a leak of various residues, gas or water, it is possible to drill one or more holes such as 12 in the tube, prior to the installation of the sleeve. These holes can pass right through the wall of the tube, as shown. It is also possible to leave a small residual thickness of metal in the tube, this then serving as a safety membrane in the event of a pressure build-up in the space 11. This or these holes can also help facilitate the creation of the connection between the tube and the sleeve, especially during the welding operation, where the trapped gas could hinder the closing of the weld pool.
On peut substituer éventuellement aux opérations de soudage par le procédé à l'arc sous gaz inerte avec électrode de tungstène des soudages par faisceau laser ou par faisceau électronique.The welding operations by the arc process under inert gas with tungsten electrode can optionally be substituted for laser beam or electron beam welds.
On peut contrôler la qualité des soudures par des moyens non destructifs tels que l'examen endoscopique, le ressuage, les courants de Foucault et les ultra-sons.The quality of the welds can be controlled by non-destructive means such as endoscopic examination, penetrant testing, eddy currents and ultrasound.
Claims (14)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR8616231 | 1986-11-21 | ||
FR8616231A FR2607235B1 (en) | 1986-11-21 | 1986-11-21 | METHOD FOR REPAIRING OR PROTECTING AN END OF A METAL HEAT EXCHANGER TUBE, AND SLEEVE FOR IMPLEMENTING SAME |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0271739A1 EP0271739A1 (en) | 1988-06-22 |
EP0271739B1 true EP0271739B1 (en) | 1990-10-03 |
Family
ID=9341064
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP87117143A Expired - Lifetime EP0271739B1 (en) | 1986-11-21 | 1987-11-20 | Process for the repair or protection of one extremity of a metallic heat exchanger tube, and sleeve for carrying it out |
Country Status (9)
Country | Link |
---|---|
US (1) | US4960650A (en) |
EP (1) | EP0271739B1 (en) |
JP (1) | JPS63153398A (en) |
KR (1) | KR880006523A (en) |
DE (1) | DE3765402D1 (en) |
ES (1) | ES2017991B3 (en) |
FR (1) | FR2607235B1 (en) |
IN (1) | IN172043B (en) |
ZA (1) | ZA878663B (en) |
Families Citing this family (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB8920382D0 (en) * | 1989-09-08 | 1989-10-25 | Nnc Ltd | Heat exchangers |
FR2652440B1 (en) * | 1989-09-27 | 1993-12-03 | Framatome | METHOD FOR REPAIRING A TUBE SUCH AS A STEAM GENERATOR TUBE. |
US5430270A (en) * | 1993-02-17 | 1995-07-04 | Electric Power Research Institute, Inc. | Method and apparatus for repairing damaged tubes |
US5372391A (en) * | 1993-02-22 | 1994-12-13 | The United States Of America As Represented By The United States Department Of Energy | Internal pipe attachment mechanism |
US5392322A (en) * | 1993-11-22 | 1995-02-21 | General Electric Company | Shroud repair clamp |
FR2726885A1 (en) * | 1994-11-15 | 1996-05-15 | Framatome Sa | RESISTANT AND WATERPROOF FIXING METHOD OF A CUFF INSIDE A METAL TUBE AND REPAIR CUFF OF A METAL TUBE |
FR2736989B1 (en) * | 1995-07-19 | 1997-08-22 | Gec Alsthom Stein Ind | DEVICE INTENDED TO BE FIXED TIGHTLY ON AT LEAST ONE CYLINDRICAL ELEMENT |
US7551705B2 (en) * | 2003-12-11 | 2009-06-23 | Areva Np, Inc. | Fuel assembly top nozzle repair sleeve and method for repairing a fuel assembly |
DE102004056619B4 (en) * | 2004-03-09 | 2007-06-06 | BRÜNDERMANN, Georg | Process for the production of a heat exchanger partition with an armor and heat exchanger partition |
WO2005087426A1 (en) * | 2004-03-09 | 2005-09-22 | Bruendermann Georg | Method for producing a heat exchanger partition with an armor-plating, and a heat exchanger partition |
US9101997B2 (en) * | 2008-09-11 | 2015-08-11 | Siemens Energy, Inc | Asymmetric heat sink welding using a penetration enhancing compound |
US20150105212A1 (en) * | 2013-10-14 | 2015-04-16 | Caterpillar Inc. | System and method for salvaging a pin-bore assembly |
RU2675952C2 (en) * | 2014-01-10 | 2018-12-25 | Эуротекника Меламине, Люксембург, Цвайгнидерлассунг ин Иттиген | Tube heat exchange assembly and apparatus, in particular reactor for production of melamine comprising such heat exchange assembly |
CN114182088B (en) * | 2021-12-08 | 2023-10-13 | 中国石油大学(华东) | Local heat treatment method for reducing stress corrosion cracking risk of welded joint of heat exchange tube and tube plate of shell-and-tube heat exchanger |
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GB471413A (en) * | 1935-12-02 | 1937-09-02 | Hall & Kay Ltd | Improvements in or relating to metal sockets, bushes, ferrules, rivets and the like |
US3064344A (en) * | 1956-09-24 | 1962-11-20 | Chicago Bridge & Iron Co | Method of producing lined vessels |
GB1143590A (en) * | 1965-04-14 | |||
US3792603A (en) * | 1972-07-26 | 1974-02-19 | Glaenzer Spicer Sa | Apparatus for assembling two parts into interlocked and interfitting relationship |
CH581200A5 (en) * | 1974-04-27 | 1976-10-29 | Bes Sa | |
USRE30802E (en) * | 1976-03-26 | 1981-11-24 | Combustion Engineering, Inc. | Method of securing a sleeve within a tube |
US4028789A (en) * | 1976-03-29 | 1977-06-14 | Westinghouse Electric Corporation | Method of installing a sleeve in one end of a tube |
US4411456A (en) * | 1976-04-02 | 1983-10-25 | Martin Charles F | Apparatus, methods, and joints for connecting tubular members |
JPS56149596A (en) * | 1980-04-21 | 1981-11-19 | Mitsubishi Heavy Ind Ltd | Repairing method of heat transmitting fine tube for heat exchanger |
US4368571A (en) * | 1980-09-09 | 1983-01-18 | Westinghouse Electric Corp. | Sleeving method |
JPS5790595A (en) * | 1980-11-27 | 1982-06-05 | Mitsubishi Heavy Ind Ltd | Repairing method of heat transfer pipe |
JPS57196097A (en) * | 1981-05-26 | 1982-12-01 | Mitsubishi Heavy Ind Ltd | Repairing method of heat exchanger tube |
JPS57196096A (en) * | 1981-05-26 | 1982-12-01 | Mitsubishi Heavy Ind Ltd | Repairing method of heat exchanger tube |
US4641409A (en) * | 1982-09-23 | 1987-02-10 | Westinghouse Electric Corp. | Reconstituting a nuclear reactor fuel assembly |
US4592577A (en) * | 1982-09-30 | 1986-06-03 | The Babcock & Wilcox Company | Sleeve type repair of degraded nuclear steam generator tubes |
US4505017A (en) * | 1982-12-15 | 1985-03-19 | Combustion Engineering, Inc. | Method of installing a tube sleeve |
EP0121137A1 (en) * | 1983-04-04 | 1984-10-10 | Combustion Engineering, Inc. | Seal welded tube sleeve |
US4513786A (en) * | 1983-04-14 | 1985-04-30 | Combustion Engineering, Inc. | Mechanical tube plub |
US4580426A (en) * | 1984-02-27 | 1986-04-08 | Westinghouse Electric Corp. | Hybrid expansion apparatus and process |
JPS60211289A (en) * | 1984-04-05 | 1985-10-23 | Mitsubishi Heavy Ind Ltd | Repair of tube |
FR2572800B1 (en) * | 1984-11-06 | 1988-10-14 | Framatome Sa | METHOD FOR REPAIRING A TUBE OF A STEAM GENERATOR BY LINING AND A SHIRT FOR REPAIRING THIS TUBE |
US4713870A (en) * | 1985-03-26 | 1987-12-22 | Raychem Corporation | Pipe repair sleeve apparatus and method of repairing a damaged pipe |
JP2785518B2 (en) * | 1991-06-24 | 1998-08-13 | 日産自動車株式会社 | Glove box damper mounting structure |
-
1986
- 1986-11-21 FR FR8616231A patent/FR2607235B1/en not_active Expired - Lifetime
-
1987
- 1987-11-18 IN IN992/DEL/87A patent/IN172043B/en unknown
- 1987-11-19 ZA ZA878663A patent/ZA878663B/en unknown
- 1987-11-20 JP JP62293866A patent/JPS63153398A/en active Pending
- 1987-11-20 EP EP87117143A patent/EP0271739B1/en not_active Expired - Lifetime
- 1987-11-20 DE DE8787117143T patent/DE3765402D1/en not_active Expired - Lifetime
- 1987-11-20 ES ES87117143T patent/ES2017991B3/en not_active Expired - Lifetime
- 1987-11-21 KR KR870013146A patent/KR880006523A/en not_active Application Discontinuation
-
1989
- 1989-06-15 US US07/366,362 patent/US4960650A/en not_active Expired - Fee Related
Also Published As
Publication number | Publication date |
---|---|
ZA878663B (en) | 1988-05-18 |
ES2017991B3 (en) | 1991-03-16 |
KR880006523A (en) | 1988-07-23 |
JPS63153398A (en) | 1988-06-25 |
DE3765402D1 (en) | 1990-11-08 |
FR2607235A1 (en) | 1988-05-27 |
US4960650A (en) | 1990-10-02 |
EP0271739A1 (en) | 1988-06-22 |
IN172043B (en) | 1993-03-20 |
FR2607235B1 (en) | 1990-02-16 |
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