FR2810727A1 - Heat exchanger tube for car radiator comprises metal strip which is bent over to form edges with space between, tube being folded inwards to form groove into which brazing flux is introduced - Google Patents
Heat exchanger tube for car radiator comprises metal strip which is bent over to form edges with space between, tube being folded inwards to form groove into which brazing flux is introduced Download PDFInfo
- Publication number
- FR2810727A1 FR2810727A1 FR0007941A FR0007941A FR2810727A1 FR 2810727 A1 FR2810727 A1 FR 2810727A1 FR 0007941 A FR0007941 A FR 0007941A FR 0007941 A FR0007941 A FR 0007941A FR 2810727 A1 FR2810727 A1 FR 2810727A1
- Authority
- FR
- France
- Prior art keywords
- metal strip
- tube
- passages
- heat exchanger
- tube according
- 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
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
- B21C37/00—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape
- B21C37/06—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape of tubes or metal hoses; Combined procedures for making tubes, e.g. for making multi-wall tubes
- B21C37/15—Making tubes of special shape; Making tube fittings
- B21C37/151—Making tubes with multiple passages
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
- F28D1/00—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators
- F28D1/02—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid
- F28D1/03—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid with plate-like or laminated conduits
- F28D1/0391—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid with plate-like or laminated conduits a single plate being bent to form one or more conduits
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- General Engineering & Computer Science (AREA)
- Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
Abstract
Description
<U>Tube plié pour un échangeur de chaleur et échangeur de</U> <U>chaleur comportant de tels tubes</U> L'invention concerne un tube plié propre à faire partie d'un échangeur de chaleur tel que, par exemple, un radiateur de refroidissement d'un moteur de véhicule automobile. The invention relates to a folded tube suitable for being part of a heat exchanger, such as, for example, a tube of heat exchanger and a heat exchanger comprising such tubes. example, a cooling radiator of a motor vehicle engine.
Elle concerne plus particulièrement un tube plié pour un échangeur de chaleur constitué d'une bande métallique ayant une face extérieure et une face intérieure, cette bande ayant deux extrémités pliées localement vers la face intérieure du tube pour former deux bordures accolées l'une à l'autre. It relates more particularly to a folded tube for a heat exchanger consisting of a metal strip having an outer face and an inner face, this strip having two ends folded locally towards the inner face of the tube to form two edges contiguous to each other. 'other.
On connaît déj des tubes de ce type. Après pliage, ils sont assemblés avec des intercalaires ou ailettes, placés dans un four et brasés. La brasure est généralement apportée par un placage de brasure disposé sur la face extérieure de la bande métallique, tandis que la face intérieure est revêtue d'un placage anticorrosion. Tubes of this type are already known. After folding, they are assembled with spacers or fins, placed in an oven and soldered. The solder is usually provided by solder plating disposed on the outer face of the metal strip, while the inner face is coated with an anti-corrosion coating.
Pour réaliser un brasage de bonne qualité, il faut apporter un flux de brasage qui a pour fonction de protéger le métal contre l'oxydation pendant le brasage. Selon la technique actuelle le flux de brasage est déposé par trempage. Ceci se traduit par le fait que les deux faces de la bande métalli que, aussi bien la face intérieure que la face extérieure, sont revêtues de flux de brasage. Après brasage, des résidus préjudiciables à la tenue en corrosion interne du radiateur subsistent. To achieve a good quality brazing, it is necessary to provide a soldering flux whose function is to protect the metal against oxidation during soldering. According to the current technique, the brazing flux is deposited by dipping. This results in the fact that the two faces of the metal strip, both the inner face and the outer face, are coated with solder flux. After soldering, residues detrimental to the internal corrosion resistance of the radiator remain.
La présente invention a précisément pour objet un tube pour un échangeur de chaleur et un procédé de fabrication de ce tube qui remédient à ces inconvénients. The present invention specifically relates to a tube for a heat exchanger and a method of manufacturing this tube that overcomes these disadvantages.
Ce but est atteint par le fait que des passages sont formés dans l'une au moins des extrémités de la bande métallique pour l'introduction d'un flux de brasage. Grâce à ces passages, le flux de brasage peut pénétrer entre bordures accolées, ce qui évite leur oxydation. This object is achieved by the fact that passages are formed in at least one end of the metal strip for the introduction of a brazing flux. Thanks to these passages, the soldering flux can penetrate between contiguous borders, which prevents their oxidation.
Selon une variante de réalisation, des passages sont formés dans les deux extrémités de la bande métallique. ce cas, les passages d'une extrémité sont avantageusement décalés par rapport aux passages de l'autre extrémité de bande métallique. According to an alternative embodiment, passages are formed in both ends of the metal strip. in this case, the passages of one end are advantageously offset with respect to the passages of the other end of the metal strip.
Selon un mode de réalisation, les passages sont réalisés par moletage des extrémités de la bande métallique. préféren ce, bande métallique est pliée par passage dans une série de galets successifs, et le moletage est effectué avant le passage dans les galets de formage. According to one embodiment, the passages are made by knurling the ends of the metal strip. Preferably, the metal strip is folded by passing through a series of successive rollers, and the knurling is performed before passing into the forming rollers.
Les passages peuvent être réalisés sensiblement perpendicu lairement aux extrémités de la bande métallique oblique- ment rapport à ces extrémités. The passages may be substantially perpendicular to the ends of the metal strip obliquely relative to these ends.
De preférence, les passages s'étendent sur une distance supérieure à la hauteur des bordures de manière à réaliser une entrée pour le flux de brasage. Preferably, the passages extend a distance greater than the height of the borders so as to provide an inlet for the soldering flux.
L'invention concerne également un échangeur de chaleur, notamment pour un véhicule automobile, comprenant un faisceau de tubes alternant avec des intercalaires de refroidissement, dans lequel les tubes sont conformes à l'invention Enfin, l'invention concerne un procédé de fabrication d'un tube pour un échangeur de chaleur par le pliage et brasage d'une bande métallique, cette bande comportant une face intérieure et une face extérieure. The invention also relates to a heat exchanger, in particular for a motor vehicle, comprising a tube bundle alternating with cooling spacers, wherein the tubes are in accordance with the invention. Finally, the invention relates to a method of manufacturing a tube for a heat exchanger by folding and brazing a metal strip, this strip having an inner face and an outer face.
Selon procédé de l'invention, on dépose un flux de brasage sur la face extérieure du tube uniquement, de préférence par aspersion. According to the method of the invention, a soldering flux is deposited on the outside of the tube only, preferably by sprinkling.
D'autres caractéristiques et avantages de la présente invention apparaîtront encore à la lecture de la description suit d'un exemple de réalisation donné à titre purement illustratif en référence aux figures annexées. Sur ces figures figure 1 est une vue d'ensemble d'un échangeur de chaleur auquel un tube conforme à la présente invention est destiné ; figure 2 est une vue en coupe transversale d'un tube conforme à la présente invention ; - figures 3 et 4 sont des vues partielles à échelle agrandie, respectivement en coupe transversale de dessus, du tube représenté à la figure 2 ; et - figure 5 est une vue partielle, à échelle agrandie, en perspective du tube représenté sur les figures à 4. échangeur de chaleur représenté à la figure comprend un faisceau 10 monté entre deux boites collectrices 12 et 14. Le faisceau 10 est constitué d'une multiplicité tubes 16 disposés parallèlement entre eux et alternant avec des intercalaires 15. ces intercalaires, encore appeles ailettes, sont de type ondulé. Ils sont formés à partir d'un feuillard metallique qui est plié pour constituer des ondulations. Ainsi, un intercalaire 15 disposé entre deux tubes adjacents vient au contact de deux tubes par des régions d'extrémité ondulations. Other features and advantages of the present invention will become apparent upon reading the following description of an exemplary embodiment given purely by way of illustration with reference to the appended figures. In these figures Figure 1 is an overview of a heat exchanger to which a tube according to the present invention is intended; Figure 2 is a cross-sectional view of a tube according to the present invention; - Figures 3 and 4 are partial views on an enlarged scale, respectively in cross section from above, of the tube shown in Figure 2; and FIG. 5 is a partial view, on an enlarged scale, in perspective of the tube shown in FIGS. 4. The heat exchanger shown in the figure comprises a bundle 10 mounted between two collecting boxes 12 and 14. The bundle 10 consists of a plurality of tubes 16 arranged parallel to each other and alternating with spacers 15. These spacers, also called fins, are of corrugated type. They are formed from a metal strip which is folded to form undulations. Thus, a spacer 15 disposed between two adjacent tubes comes into contact with two tubes by end regions ripples.
echangeur de chaleur comprend en outre deux joues 17, encore appelées traverses, qui encadrent le faisceau et sont disposées parallèlement aux tubes 16. heat exchanger further comprises two cheeks 17, also called sleepers, which frame the beam and are arranged parallel to the tubes 16.
pièces qui constituent l'échangeur sont maintenues assemblées sur une table (non représentée) et une pression exercée sur les joues 17 dans la direction flèches F pour réaliser le maintien respectif des tubes 16, des intercalaires 15 et des joues 17 en vue de 1 opération de brasage. Le tube représenté à la figure 2 est réalisé ' partir d'une bande métallique, par exemple en aluminium, pliée en plusieurs opérations successives grâce à des galets selon une technique connue. I1 s'agit d'un tube plat qui présente une section sensiblement rectangulaire très aplatie comprenant deux grandes faces 18 et 20 reliées par deux faces semi- circulaires 21. parts constituting the exchanger are held together on a table (not shown) and a pressure exerted on the cheeks 17 in the direction of arrows F to achieve the respective holding tubes 16, tabs 15 and cheeks 17 for 1 operation brazing. The tube shown in Figure 2 is made from a metal strip, for example aluminum, folded in several successive operations with rollers according to a known technique. It is a flat tube which has a substantially flattened rectangular section comprising two large faces 18 and 20 connected by two semicircular faces 21.
La grande face 18 est constituée de deux parties 24 26 qui se rejoignent. La bande métallique est repliée à angle droit aux extremités des parties 24 et 26 pour former des bordures accolées et 30 qui prennent appui sur la grande face 20, du côté intérieur du tube. Ces bordures 28 et 30 pour fonction une part de délimiter des canaux de circulation distincts 32 et 34 pour un fluide, et d'autre part de constituer une entretoise entre les deux grandes faces 18 et 20 afin garantir leur parallélisme et leur planéite. The large face 18 consists of two parts 24 26 that meet. The metal strip is folded at right angles to the ends of the parts 24 and 26 to form contiguous borders and which bear on the large face 20, the inner side of the tube. These borders 28 and 30 for one function to delimit separate circulation channels 32 and 34 for a fluid, and secondly to form a spacer between the two major faces 18 and 20 to ensure their parallelism and their flatness.
Afin de permettre le brasage du tube, la bande métallique est recouverte extérieurement d'un placage de brasage (non représente), la face intérieure étant recouverte d'un placage anticorrosion (non représenté). Comme on peut le voir, les bordures et 30 sont accolées l'une à l'autre telle sorte que l'interstice qui peut subsister entre elles est trop réduit pour pouvoir amener un flux de brasage entre ces bordures. In order to allow the brazing of the tube, the metal strip is covered externally with a solder plating (not shown), the inner face being covered with an anticorrosion coating (not shown). As can be seen, the borders and are contiguous to each other so that the gap that can remain between them is too small to be able to bring a soldering flux between these borders.
C'est pourquoi, conformément à l'invention, comme on peut le voir plus particulièrement sur les figures 3 à 5, des passages 38 ont été formés dans les bordures 28 et . Bien que, dans l'exemple de réalisation décrite, des passages 38 aient été prévus dans chacune des deux bordures 28 30, il est possible également, selon une variante de réalisation, de ne prévoir de tels passages que dans l'une des deux bordures. Dans l'exemple de réalisation décrit, les passages sont sensiblement perpendiculaires aux grandes faces 18 et 20. Cette caractéristique n'est pas essentielle et l'on pourrait également prévoir, conformément à l'invention, des passages disposés obliquement par rapport à ces parois. De même, dans 'exemple de réalisation décrit, les passages sont rectili gnes, mais ils pourraient présenter également une autre forme, par exemple courbe ou en forme de sinusoïde. De préférence, comme on peut le voir sur la figure 4, les sages sont disposés en alternance, un passage 38 de bordure 30 étant disposé entre deux passages de la bordure et réciproquement. Therefore, according to the invention, as can be seen more particularly in Figures 3 to 5, passages 38 have been formed in the borders 28 and. Although, in the embodiment described, passages 38 have been provided in each of the two edges 28 30, it is also possible, according to an alternative embodiment, to provide such passages only in one of the two borders . In the embodiment described, the passages are substantially perpendicular to the large faces 18 and 20. This characteristic is not essential and one could also provide, in accordance with the invention, passages arranged obliquely with respect to these walls. . Similarly, in the embodiment described, the passages are rectilinear, but they could also have another shape, for example curved or sinusoid-shaped. Preferably, as can be seen in Figure 4, the wise are arranged alternately, a passage 38 of border 30 being disposed between two passages of the border and vice versa.
préférence encore, comme on peut le voir sur la figure la longueur du passage 38 formé à l'extrémité des bandes métalliques est sensiblement supérieure à la hauteur bordures 28 et 30 de manière à constituer une entrée 40 facilite l'introduction du flux de brasage. more preferably, as can be seen in the figure the length of the passage 38 formed at the end of the metal strips is substantially greater than the height of the edges 28 and 30 so as to constitute an inlet 40 facilitates the introduction of the solder flux.
Ce flux de brasage est déposé uniquement sur la face exté rieure de la bande métallique, de préférence par aspersion, mais il pourrait aussi être apporté par une autre technique, par exemple par trempage.This brazing flux is deposited only on the outer face of the metal strip, preferably by sprinkling, but it could also be provided by another technique, for example by dipping.
Claims (12)
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR0007941A FR2810727B1 (en) | 2000-06-21 | 2000-06-21 | FOLDED TUBE FOR A HEAT EXCHANGER AND HEAT EXCHANGER COMPRISING SUCH TUBES |
JP2001184960A JP2002071287A (en) | 2000-06-21 | 2001-06-19 | Tube for heat exchanger |
US09/884,447 US20020020522A1 (en) | 2000-06-21 | 2001-06-20 | Folded tube for heat exchanger, and heat exchanger including such tubes |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR0007941A FR2810727B1 (en) | 2000-06-21 | 2000-06-21 | FOLDED TUBE FOR A HEAT EXCHANGER AND HEAT EXCHANGER COMPRISING SUCH TUBES |
Publications (2)
Publication Number | Publication Date |
---|---|
FR2810727A1 true FR2810727A1 (en) | 2001-12-28 |
FR2810727B1 FR2810727B1 (en) | 2003-09-26 |
Family
ID=8851507
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
FR0007941A Expired - Lifetime FR2810727B1 (en) | 2000-06-21 | 2000-06-21 | FOLDED TUBE FOR A HEAT EXCHANGER AND HEAT EXCHANGER COMPRISING SUCH TUBES |
Country Status (3)
Country | Link |
---|---|
US (1) | US20020020522A1 (en) |
JP (1) | JP2002071287A (en) |
FR (1) | FR2810727B1 (en) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2005043026A (en) * | 2003-07-25 | 2005-02-17 | Toyo Radiator Co Ltd | Flat tube for heat exchanger |
GB2486671A (en) * | 2010-12-22 | 2012-06-27 | Denso Marston Ltd | A Heat Exchanger, a Tube for a Heat Exchanger, a Method of making a tube for a Heat Exchanger and a Method of Making a Heat Exchanger |
DE102017212271A1 (en) | 2017-07-18 | 2019-01-24 | Mahle International Gmbh | flat tube |
US11346616B2 (en) * | 2020-03-27 | 2022-05-31 | Denso International America, Inc. | Dimpled heat exchanger tube |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2061788A (en) * | 1979-11-02 | 1981-05-20 | Bicc Ltd | A method of shaping metal sheet |
JPH06123571A (en) * | 1992-08-26 | 1994-05-06 | Nippondenso Co Ltd | Heat exchanger |
EP0632245A1 (en) * | 1993-07-01 | 1995-01-04 | THERMAL-WERKE Wärme-, Kälte-, Klimatechnik GmbH | Water-air heat exchanger of aluminium for motor vehicles |
DE19518657A1 (en) * | 1995-04-26 | 1996-10-31 | Lingemann Helmut Gmbh & Co | Multi-chamber flat tube for heat exchangers and process for its manufacture |
FR2757258A1 (en) * | 1996-12-12 | 1998-06-19 | Valeo Equip Electr Moteur | Flat multi=channel tube for heat exchanger |
DE19857510A1 (en) * | 1997-12-23 | 1999-07-01 | Valeo Thermique Moteur Sa | Bent heat exchanger tube used in motor vehicle radiator, made by soldering strip metal |
-
2000
- 2000-06-21 FR FR0007941A patent/FR2810727B1/en not_active Expired - Lifetime
-
2001
- 2001-06-19 JP JP2001184960A patent/JP2002071287A/en active Pending
- 2001-06-20 US US09/884,447 patent/US20020020522A1/en not_active Abandoned
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2061788A (en) * | 1979-11-02 | 1981-05-20 | Bicc Ltd | A method of shaping metal sheet |
JPH06123571A (en) * | 1992-08-26 | 1994-05-06 | Nippondenso Co Ltd | Heat exchanger |
EP0632245A1 (en) * | 1993-07-01 | 1995-01-04 | THERMAL-WERKE Wärme-, Kälte-, Klimatechnik GmbH | Water-air heat exchanger of aluminium for motor vehicles |
DE19518657A1 (en) * | 1995-04-26 | 1996-10-31 | Lingemann Helmut Gmbh & Co | Multi-chamber flat tube for heat exchangers and process for its manufacture |
FR2757258A1 (en) * | 1996-12-12 | 1998-06-19 | Valeo Equip Electr Moteur | Flat multi=channel tube for heat exchanger |
DE19857510A1 (en) * | 1997-12-23 | 1999-07-01 | Valeo Thermique Moteur Sa | Bent heat exchanger tube used in motor vehicle radiator, made by soldering strip metal |
Non-Patent Citations (1)
Title |
---|
PATENT ABSTRACTS OF JAPAN vol. 018, no. 418 (M - 1650) 5 August 1994 (1994-08-05) * |
Also Published As
Publication number | Publication date |
---|---|
FR2810727B1 (en) | 2003-09-26 |
US20020020522A1 (en) | 2002-02-21 |
JP2002071287A (en) | 2002-03-08 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP2294348B1 (en) | Condenser | |
WO2001050080A2 (en) | Multichannel tube heat exchanger | |
CA2747353A1 (en) | Heat exchanger comprising tubes with grooved fins | |
FR2845153A1 (en) | Brazed plate heat exchanger fin is made from thick sheet metal with a repeated corrugated pattern having a set geometrical pitch | |
FR2878946A1 (en) | PROFILE LAMINATED METAL TUBE AND METHOD OF MANUFACTURING THE SAME | |
FR2967765A1 (en) | ARMABLE COMPONENT AND HEAT EXCHANGER HAVING THE SAME | |
FR2997485A1 (en) | THERMAL EXCHANGER, IN PARTICULAR FOR MOTOR VEHICLE | |
EP1780489A1 (en) | Header box for heat exchanger | |
FR2770632A1 (en) | Heat exchanger with reinforced collector | |
FR2810727A1 (en) | Heat exchanger tube for car radiator comprises metal strip which is bent over to form edges with space between, tube being folded inwards to form groove into which brazing flux is introduced | |
EP1174673B1 (en) | Heat exchange module, more particularly for automotive vehicle, and process for manufacturing same | |
FR2660425A1 (en) | FLAT TUBE HEAT EXCHANGER. | |
EP2655000A1 (en) | Brazing method for a heat exchanger, and corresponding tube and heat exchanger | |
FR2832788A1 (en) | Profile for tubes in heat exchangers used in motor vehicles, uses folded metal sheet to form tube and bends one edge over so that it rests on other wall of tube, providing strength to the tube during manufacture | |
FR2823840A1 (en) | Heat exchanger folded tube is obtained by folding metal strip over itself to define two channels separated by partition to form transverse member created by strip folded edges | |
FR2892807A1 (en) | Reinforced collector for e.g. radiator, has ribs between holes of flat plate and raised lateral edges interconnected by curved segment in which other ribs are provided, where each rib has convexity extending in respective direction | |
FR3062901A1 (en) | THERMAL HEAT EXCHANGER TUBE, HEAT EXCHANGER AND CORRESPONDING TUBE ASSEMBLY METHOD | |
EP2068106A1 (en) | Corrugated fin with louvers for a heat exchanger | |
FR2770634A1 (en) | Twin-channel folded metal tube for heat exchanger | |
FR2810729A1 (en) | Heat exchanger tube for car radiator comprises metal strip which has external layer of brazing and is bent inwards to form tube with side walls whose ends rest against inner surface of sheet and have brazed coating | |
FR2817334A1 (en) | Brazed flat tube heat exchanger has tube ends cut away and folded outwards for brazing inside manifold | |
FR2810728A1 (en) | Heat exchanger tube for car radiator comprises metal strip which is bent over, ends of side walls of tubes fitting into depressions in base of strip | |
FR2836546A1 (en) | Heat exchanger folded tube is obtained by folding metallic band to delimit two parallel channels with separate upper faces and common lower edge, band lateral edges folded to form partition between channels | |
FR2799824A1 (en) | Flat multi-channel tube for heat exchanger esp in motor vehicle has outer surface grooved in line with partitions to give even wall thickness | |
FR2925665A1 (en) | Brazed tube for circulating air in heat exchanger of vehicle, has thermal insulation brace placed between channels and parallel to one of large flat sides of cover, where rectangular shaped openings are provided in thermal insulation brace |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PLFP | Fee payment |
Year of fee payment: 17 |
|
PLFP | Fee payment |
Year of fee payment: 18 |