EP0180046A2 - Heating boiler - Google Patents

Heating boiler Download PDF

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Publication number
EP0180046A2
EP0180046A2 EP85112372A EP85112372A EP0180046A2 EP 0180046 A2 EP0180046 A2 EP 0180046A2 EP 85112372 A EP85112372 A EP 85112372A EP 85112372 A EP85112372 A EP 85112372A EP 0180046 A2 EP0180046 A2 EP 0180046A2
Authority
EP
European Patent Office
Prior art keywords
outer shell
heating
boiler
heat exchange
thermal conductivity
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.)
Withdrawn
Application number
EP85112372A
Other languages
German (de)
French (fr)
Other versions
EP0180046A3 (en
Inventor
Rolf Dr. Noack
Günter Höfeld
Manfred Sziburies
Günter Schneider
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.)
Bosch Thermotechnik GmbH
Original Assignee
Buderus AG
Buderus Heiztechnik GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Buderus AG, Buderus Heiztechnik GmbH filed Critical Buderus AG
Publication of EP0180046A2 publication Critical patent/EP0180046A2/en
Publication of EP0180046A3 publication Critical patent/EP0180046A3/en
Withdrawn legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H1/00—Water heaters, e.g. boilers, continuous-flow heaters or water-storage heaters
    • F24H1/22—Water heaters other than continuous-flow or water-storage heaters, e.g. water heaters for central heating
    • F24H1/40—Water heaters other than continuous-flow or water-storage heaters, e.g. water heaters for central heating with water tube or tubes
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H9/00—Details
    • F24H9/0005—Details for water heaters
    • F24H9/0036—Dispositions against condensation of combustion products
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F1/00—Tubular elements; Assemblies of tubular elements
    • F28F1/003—Multiple wall conduits, e.g. for leak detection

Definitions

  • the invention relates to a heating boiler according to the preamble of claim 1.
  • a heating boiler of this type can be found in DE-OS 1 778 832.
  • the formation of the heat exchange surface from two shells arranged at a distance from one another is intended to prevent undercooling of the heating gases with a feared formation of condensate if the temperature falls below the dew point.
  • a narrowly defined distance between the shells is considered necessary, which may have to be guaranteed by a thin insulating layer, such as an asbestos sheet.
  • the effects of cool boiler water on the heating gases are thereby to be reduced without excessive deterioration in the heat transfer from the heating gases to the boiler water.
  • the distance can now be chosen to be significantly larger.
  • the material with the existing thermal conductivity leads to the same effects as the previous insulation material at larger distances.
  • the heat transfer is probably limited, but only so much that the heat exchange surface still fully fulfills its actual purpose.
  • a compressed bulk material preferably a quartz powder with different grain sizes, is recommended as the material for the intermediate layer. This then forms a tight packing with sufficient thermal conductivity.
  • the thermal conductivity values can be different in different areas due to the different material composition. In zones with higher heating gas temperatures, a material with better thermal conductivity values is recommended than in other zones.
  • thermal conductivity values should increase with increasing distances between the two shells. This ensures the necessary heat transfer and still maintains an adequate insulation effect.
  • the application of the invention is particularly recommended for heat exchange surfaces made of tubular bodies pushed into one another.
  • tubular bodies These are specifically flue gas pipes in boilers.
  • the two tubular bodies are inserted into one another and the circumferential gap is sealed at the lower end.
  • the space between the standing unit is then filled with the bulk material while vibrating. This creates a good pre-compression of the material.
  • the inner tubular body is calibrated to a desired internal dimension, i.e. slightly expanded. This leads to a further compression of the material.
  • the finished pipe element can then be stamped as a unit and installed in the boiler.
  • the accompanying drawing shows an embodiment of the invention in a single figure as a longitudinal section through a smoke tube.
  • the heat exchange surface consists of two spaced-apart shells 1, 2, namely an outer tubular body and an inner tubular body. Since precise dimensional tolerances have been deliberately avoided, the circumferential gap between the tubular bodies is relatively large. The gap is closed at both ends by a weld seam 3, 4 and filled with a material 5 with existing thermal conductivity, namely a bulk material such as quartz powder, in a tight packing. The compression was carried out by vibration during filling and by a subsequent calibration of the inner tube body.

Abstract

A heating boiler with a heat exchange surface consisting of an inner shell (2) and an outer shell (1) has between the two shells (1, 2) a material (5) with existing thermal conductivity which is introduced after they have been joined together. The material, preferably a compressed bulk material such as quartz powder, reduces the effect of the cold boiler water on the heating gases without hindering too greatly the opposite-running heat flow. <IMAGE>

Description

Die Erfindung bezieht sich auf einen Heizungskessel nach dem Oberbegriff des Patentanspruches 1.The invention relates to a heating boiler according to the preamble of claim 1.

Ein Heizungskessel dieser Art ist der DE-OS 1 778 832 zu entnehmen. Durch die Ausbildung der Wärmeaustauschfläche aus zwei im Abstand zueinander angeordneten Schalen soll dabei eine Unterkühlung der Heizgase mit einer gefürchteten Kondensatbildung bei Taupunktsunterschreitungen verhindert werden. Hierzu wird ein eng begrenzter Abstand zwischen den Schalen für erforderlich gehalten, der ggf. durch eine dünne Isolierschicht, etwa ein Asbestblatt, zu garantieren ist. Einwirkungen von kühlem Kesselwasser auf die Heizgase sollen dadurch ohne übermäßige Verschlechterung des Wärmeüberganges von den Heizgasen zu dem Kesselwasser vermindert werden.A heating boiler of this type can be found in DE-OS 1 778 832. The formation of the heat exchange surface from two shells arranged at a distance from one another is intended to prevent undercooling of the heating gases with a feared formation of condensate if the temperature falls below the dew point. For this purpose, a narrowly defined distance between the shells is considered necessary, which may have to be guaranteed by a thin insulating layer, such as an asbestos sheet. The effects of cool boiler water on the heating gases are thereby to be reduced without excessive deterioration in the heat transfer from the heating gases to the boiler water.

Zur Erzielung des vorgeschlagenen, eng begrenzten Abstandes sind recht genaue Fertigungstoleranzen einzuhalten. Das trifft schon bei der Herstellung der Einzelschalen und auch bei der Erstellung der fertigen Wärmeaustauschfläche zu. Speziell ist dieses bei Wärmeaustauschflächen aus ineinander geschobenen Rohrkörpern der Fall. Nur genau tolerierte Rohrkörper können mit dem geforderten geringen Abstand ineinandergefügt und durch ein anschließendes Verformen des Innenrohres auf den gewünschten, noch enger begrenzten Abstand gebracht werden. Somit ist sowohl zur Herstellung der Einzelteile als auch der fertigen Einheit ein sehr großer Aufwand erforderlich.In order to achieve the proposed, narrowly limited distance, very precise manufacturing tolerances must be observed. This applies to the manufacture of the individual shells and also to the creation of the finished heat exchange surface. This is especially the case with heat exchange surfaces made of tubular bodies pushed into one another. Only precisely tolerated tubular bodies can be inserted into one another with the required small distance and then brought to the desired, even more narrowly limited distance by subsequently deforming the inner tube. This means that both the manufacture of the individual parts and the finished unit require a great deal of effort.

Der erforderliche Aufwand zur Erstellung einer doppelschaligen Wärmeaustauschfläche eines Heizungskessels soll verringert werden.The effort required to create a double-shell heat exchange surface of a heating boiler should be reduced.

Erfindungsgemäß wird dieses erreicht durch das im Kennzeichen des Patentanspruches 1 genannte Merkmal.According to the invention this is achieved by the feature mentioned in the characterizing part of patent claim 1.

Statt des bisher erforderlichen, genau definierten Abstandes mit einer gut isolierenden Zwischenschicht kann jetzt der Abstand wesentlich größer gewählt werden. Das Material mit der vorhandenen Wärmeleitfähigkeit führt bei größeren Abständen genau zu denselben Effekten wie das bisherige Isoliermaterial. Der Wärmedurchgang wird wohl begrenzt, jedoch nur soviel, daß die Wärmeaustauschfläche ihren eigentlichen Zweck noch voll erfüllt. Infolge des jetzt vorgesehenen, größeren Abstandes kann mit wesentlich größeren Fertigungstoleranzen gearbeitet werden, weil diese keinen entscheidenden Einfluß mehr auf den Wärmedurchgang haben. Sie sind nämlich klein im Verhältnis zur Schichtstärke des erfindungsgemäß zwischengefügten Materiales. Als Material für die Zwischenschicht empfiehlt sich ein verdichtetes Schüttgut, vorzugsweise ein Quarzpulver mit unterschiedlicher Körnung. Dieses bildet dann eine dichte Packung mit einer noch ausreichenden Wärmeleitfähigkeit.Instead of the previously required, precisely defined distance with a well insulating intermediate layer, the distance can now be chosen to be significantly larger. The material with the existing thermal conductivity leads to the same effects as the previous insulation material at larger distances. The heat transfer is probably limited, but only so much that the heat exchange surface still fully fulfills its actual purpose. As a result of the larger distance now envisaged, it is possible to work with much greater manufacturing tolerances because these no longer have a decisive influence on the heat transfer. Namely, they are small in relation to the layer thickness of the material interposed according to the invention. A compressed bulk material, preferably a quartz powder with different grain sizes, is recommended as the material for the intermediate layer. This then forms a tight packing with sufficient thermal conductivity.

Die Wärmeleitwerte können durch unterschiedliche Materialzusammensetzung in unterschiedlichen Bereichen verschieden sein. In Zonen mit höheren Heizgastemperaturen empfiehlt ein Material mit besseren Wärmeleitwerten als in anderen Zonen.The thermal conductivity values can be different in different areas due to the different material composition. In zones with higher heating gas temperatures, a material with better thermal conductivity values is recommended than in other zones.

Ferner sollten die Wärmeleitwerte mit steigenden Abständen zwischen den beiden Schalen ansteigen. Dadurch wird der erforderliche Wärmeübergang gewährleistet und dennoch eine noch ausreichende Isolierwirkung eingehalten.Furthermore, the thermal conductivity values should increase with increasing distances between the two shells. This ensures the necessary heat transfer and still maintains an adequate insulation effect.

Wie schon angedeutet, empfiehlt sich die Anwendung der Erfindung besonders bei Wärmeaustauschflächen aus ineinander geschobenen Rohrkörpern. Das sind speziell Rauchgasrohre in Heizkesseln. Zu deren Herstellung werden die beiden Rohrkörper ineinander gefügt und der umlaufende Spalt am unteren Ende dicht verschlossen. Der Zwischenraum der stehenden Einheit wird dann bei gleichzeitigem Vibrieren mit dem Schüttgut gefüllt. Hierdurch entsteht eine gute Vorverdichtung des Materiales. Nach einem Verschließen des umlaufenden Spaltes am oberen Ende wird der innere Rohrkörper auf ein gewünschtes Innenmaß kalibriert, d.h. geringfügig aufgeweitet. Dieses führt zu einer weiteren Verdichtung des Materiales. Das fertige Rohrelement kann dann als Einheit ggfs. mit Einprägungen versehen und in den Heizungskessel eingebaut werden.As already indicated, the application of the invention is particularly recommended for heat exchange surfaces made of tubular bodies pushed into one another. These are specifically flue gas pipes in boilers. To manufacture them, the two tubular bodies are inserted into one another and the circumferential gap is sealed at the lower end. The space between the standing unit is then filled with the bulk material while vibrating. This creates a good pre-compression of the material. After closing the circumferential gap at the upper end, the inner tubular body is calibrated to a desired internal dimension, i.e. slightly expanded. This leads to a further compression of the material. The finished pipe element can then be stamped as a unit and installed in the boiler.

Die beigefügte Zeichnung stellt in einer einzigen Figur ein Ausführungsbeispiel der Erfindung als Längsschnitt durch ein Rauchrohr dar.The accompanying drawing shows an embodiment of the invention in a single figure as a longitudinal section through a smoke tube.

Die Wärmeaustauschfläche besteht aus zwei im Abstand zueinander angeordneten Schalen 1,2, nämlich einem äußeren Rohrkörper und einem inneren Rohrkörper..Da bewußt auf die Einhaltung genauer Maßtoleranzen verzichtet wurde, ist der umlaufende Spalt zwischen den Rohrkörpern relativ groß. Der Spalt ist an beiden Enden durch eine Schweißnaht 3, 4 verschlossen und mit einem Material 5 mit vorhandener Wärmeleitfähigkeit, nämlich einem Schüttgut wie Quarzpulver, in dichter Packung gefüllt. Das Verdichten erfolgte durch Vibration während des Einfüllens und durch ein nachträgliches Kalibrieren des inneren Rohrkörpers.The heat exchange surface consists of two spaced-apart shells 1, 2, namely an outer tubular body and an inner tubular body. Since precise dimensional tolerances have been deliberately avoided, the circumferential gap between the tubular bodies is relatively large. The gap is closed at both ends by a weld seam 3, 4 and filled with a material 5 with existing thermal conductivity, namely a bulk material such as quartz powder, in a tight packing. The compression was carried out by vibration during filling and by a subsequent calibration of the inner tube body.

Claims (6)

1. Heizungskessel mit einer Wärmeaustauschfläche aus einer Innenschale, einer im Abstand dazu angeordneten Außenschale und einer isolierenden Zwischenschicht, dadurch gekennzeichnet, daß die Zwischenschicht aus einem nach dem Zusammenfügen der Außenschale (1) und der Innenschale (2) eingebrachten Material (5) mit vorhandener Wärmeleitfähigkeit besteht.1. A heating boiler with a heat exchange surface made of an inner shell, an outer shell spaced apart therefrom and an insulating intermediate layer, characterized in that the intermediate layer consists of a material (5) introduced after the outer shell (1) and the inner shell (2) have been joined together There is thermal conductivity. 2. Heizungskessel nach Anspruch 1, dadurch gekennzeichnet, daß das Material aus einem verdichteten Schüttgut, vorzugsweise einem Quarzpulver mit unterschiedlicher Körnung besteht.2. Boiler according to claim 1, characterized in that the material consists of a compressed bulk material, preferably a quartz powder with different grain sizes. 3. Heizungskessel nach den Ansprüchen 1 und 2, dadurch gekennzeichnet, daß in Zonen mit höheren Heizgastemperaturen ein Material mit besseren Wärmeleitwerten angeordnet ist als in Zonen mit niedrigeren Heizgastemperaturen.3. Boiler according to claims 1 and 2, characterized in that a material with better thermal conductivities is arranged in zones with higher heating gas temperatures than in zones with lower heating gas temperatures. 4. Heizungskessel nach den Ansprüchen 1 und 2, dadurch gekennzeichnet, daß bei größeren Abständen zwischen der Innen- und der Außenschale ein Material mit besseren Wärmeleitwerten eingesetzt ist als bei geringeren Abständen.4. Heating boiler according to claims 1 and 2, characterized in that a material with better thermal conductivity values is used at larger distances between the inner and the outer shell than at smaller distances. 5. Verfahren zur Herstellen der Wärmeaustauschfläche eines Heizungskessels mit rohrförmigen Heizgaskanälen nach Patentanspruch 1, dadurch gekennzeichnet, daß ein Rohrkörper als Innenschale (2) mit Abstand in einen Rohrkörper als Außenschale (1) eingefügt und der umlaufende Spalt am unteren Ende dicht verschlossen wird, daß in den Zwischenraum der stehenden Einheit bei gleichzeitigem Vibrieren ein Material (5) eingefüllt und dann der umlaufende Spalt am oberen Ende dicht verschlossen wird und daß anschließend der innere Rohrkörper kalibriert wird. 5. A method for producing the heat exchange surface of a heating boiler with tubular heating gas channels according to claim 1, characterized in that a tubular body as the inner shell (2) is inserted at a distance into a tubular body as the outer shell (1) and the circumferential gap is sealed at the lower end, that a material (5) is poured into the space between the standing unit while vibrating and then the peripheral gap is sealed at the upper end and that the inner tube body is then calibrated. 6. Verfahren nach Anspruch 5, dadurch gekennzeichnet, daß in die Wände der fertigen Doppelrohr-Einheit Einprägungen eingebracht werden, wobei das eingefüllte und verdichtete Material in dem Zwischenraum erhalten bleibt.6. The method according to claim 5, characterized in that impressions are introduced into the walls of the finished double tube unit, the filled and compressed material being retained in the intermediate space.
EP85112372A 1984-11-02 1985-09-30 Heating boiler Withdrawn EP0180046A3 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3440006 1984-11-02
DE19843440006 DE3440006A1 (en) 1984-11-02 1984-11-02 HEATING BOILER

Publications (2)

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EP0180046A2 true EP0180046A2 (en) 1986-05-07
EP0180046A3 EP0180046A3 (en) 1988-01-20

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EP85112372A Withdrawn EP0180046A3 (en) 1984-11-02 1985-09-30 Heating boiler

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DE (1) DE3440006A1 (en)
DK (1) DK504685A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2603693A1 (en) * 1986-09-05 1988-03-11 Toshiba Kk CALIBRATED TUBULAR HEAT EXCHANGER
EP1008819A3 (en) * 1998-12-11 2002-09-25 Vulcano-Sadeca, S.A. Hot water generator for operation at low temperature
WO2023099840A1 (en) * 2021-12-02 2023-06-08 Commissariat A L'energie Atomique Et Aux Energies Alternatives Method for manufacturing a double-layered heat exchange wall

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3706645A1 (en) * 1987-03-02 1988-09-15 Doerhoefer Dofa Kessel Und App Heat exchanger
DE3822238A1 (en) * 1988-07-01 1990-01-04 Buderus Heiztechnik Gmbh Boiler with a tubular heating-gas flue
DE8903022U1 (en) * 1989-03-11 1990-07-19 Viessmann, Hans, Dr., 3559 Battenberg, De
DE19743422A1 (en) * 1997-10-01 1999-04-08 Weso Aurorahuette Gmbh Boiler, which uses exhaust gases to warm water

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1768069A (en) * 1927-10-20 1930-06-24 Thomas J Johnston Water-heating coil
DE2221801B2 (en) * 1972-05-04 1974-02-21 Fa. August Broetje, 2902 Rastede Heating boiler
FR2526697A1 (en) * 1982-05-13 1983-11-18 Broetje Fa August PROCESS FOR THE MANUFACTURE OF A HEATING SURFACE OF A WATER CONDENSING BOILER, COMPOSED OF AN INTERIOR ENCLOSURE AND AN OUTER ENCLOSURE, AND HEATING SURFACE MANUFACTURED BY THIS PROCESS
GB2119917A (en) * 1982-01-22 1983-11-23 Tokyo Shibaura Electric Co Refrigerant heating device

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1778832A1 (en) * 1968-06-11 1971-08-26 Thyssen Industrie Hot water boilers, in particular heating boilers
DE1957700C3 (en) * 1969-11-17 1979-01-11 Tuerk & Hillinger Gmbh & Co, 7200 Tuttlingen Device for manufacturing and compressing an electric heater
RO57797A (en) * 1970-06-29 1975-02-15
DE2208901A1 (en) * 1972-02-25 1973-08-30 Czepek & Co DEVICE FOR FILLING CERAMIC INSULATING POWDER INTO THE SHEET PIPES OF ELECTRIC TUBULAR RADIATORS
DE2525441C3 (en) * 1975-06-07 1981-04-16 Dynamit Nobel Ag, 5210 Troisdorf Electrically insulating filling for an electric tubular heater
CH628134A5 (en) * 1978-03-28 1982-02-15 Ygnis Sa FLUE GAS FLOWED HEAT EXCHANGER.

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1768069A (en) * 1927-10-20 1930-06-24 Thomas J Johnston Water-heating coil
DE2221801B2 (en) * 1972-05-04 1974-02-21 Fa. August Broetje, 2902 Rastede Heating boiler
GB2119917A (en) * 1982-01-22 1983-11-23 Tokyo Shibaura Electric Co Refrigerant heating device
FR2526697A1 (en) * 1982-05-13 1983-11-18 Broetje Fa August PROCESS FOR THE MANUFACTURE OF A HEATING SURFACE OF A WATER CONDENSING BOILER, COMPOSED OF AN INTERIOR ENCLOSURE AND AN OUTER ENCLOSURE, AND HEATING SURFACE MANUFACTURED BY THIS PROCESS

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2603693A1 (en) * 1986-09-05 1988-03-11 Toshiba Kk CALIBRATED TUBULAR HEAT EXCHANGER
EP1008819A3 (en) * 1998-12-11 2002-09-25 Vulcano-Sadeca, S.A. Hot water generator for operation at low temperature
WO2023099840A1 (en) * 2021-12-02 2023-06-08 Commissariat A L'energie Atomique Et Aux Energies Alternatives Method for manufacturing a double-layered heat exchange wall
FR3130020A1 (en) * 2021-12-02 2023-06-09 Commissariat A L'energie Atomique Et Aux Energies Alternatives Method of manufacturing a double layer heat exchange wall

Also Published As

Publication number Publication date
DE3440006A1 (en) 1986-05-07
DE3440006C2 (en) 1988-04-28
EP0180046A3 (en) 1988-01-20
DK504685A (en) 1986-05-03
DK504685D0 (en) 1985-11-01

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