EP1595025A1 - Plasmatized heat exchanger - Google Patents

Plasmatized heat exchanger

Info

Publication number
EP1595025A1
EP1595025A1 EP04710849A EP04710849A EP1595025A1 EP 1595025 A1 EP1595025 A1 EP 1595025A1 EP 04710849 A EP04710849 A EP 04710849A EP 04710849 A EP04710849 A EP 04710849A EP 1595025 A1 EP1595025 A1 EP 1595025A1
Authority
EP
European Patent Office
Prior art keywords
heat exchanger
plasma
exchanger according
coated
heat transfer
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Withdrawn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
EP04710849A
Other languages
German (de)
French (fr)
Inventor
Ludwig Hellenthal
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.)
Walzen Irle GmbH
Original Assignee
Walzen Irle 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 Walzen Irle GmbH filed Critical Walzen Irle GmbH
Publication of EP1595025A1 publication Critical patent/EP1595025A1/en
Withdrawn legal-status Critical Current

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F5/00—Elements specially adapted for movement
    • F28F5/02—Rotary drums or rollers
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21G—CALENDERS; ACCESSORIES FOR PAPER-MAKING MACHINES
    • D21G1/00—Calenders; Smoothing apparatus
    • D21G1/02—Rolls; Their bearings
    • D21G1/0246—Hard rolls
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F19/00—Preventing the formation of deposits or corrosion, e.g. by using filters or scrapers
    • F28F19/02—Preventing the formation of deposits or corrosion, e.g. by using filters or scrapers by using coatings, e.g. vitreous or enamel coatings
    • F28F19/06—Preventing the formation of deposits or corrosion, e.g. by using filters or scrapers by using coatings, e.g. vitreous or enamel coatings of metal

Definitions

  • the invention relates to a heat exchanger according to the preamble of claim 1.
  • Such heat exchangers are used for the production or finishing of web-like products in industry, predominantly in calenders.
  • the thermally applied surface coatings have the disadvantage of a relatively large porosity of the finished layer. Wear particles have the ability to penetrate these pores and the less hard matrix areas and then "wash them out”.
  • Surface-hardened forged steel rollers in addition to insufficient tempering resistance and the associated low hardness, also have an unfavorable residual stress distribution caused by surface-hardening. High tensile stresses in the area of the hardness zone negate the advantages of the good mechanical properties of forged steel.
  • New coating slips and feedstocks in paper production require increased chemical and mechanical corrosion resistance not only of the roll barrel but also of the entire roll surface which is connected to the environment and the web. Due to the enormous heat transfer capacities (> 80 kW / m), constantly increasing heat transfer temperatures, the contact surfaces exposed to the fluid heat transfer media are exposed to ever greater chemical / mechanical corrosion.
  • the invention has for its object to develop a generic heat exchanger so that he the above. Does not have disadvantages, in particular that surface hardnesses well in excess of 400-450 HV are achieved and that chemical / mechanical corrosion is minimized even with heat transfer rates> 80 kW / m.
  • the tempered forged steel rollers described above are plasma-coated at the desired locations.
  • plasma mating is used in the following as a collective term for the sub-terms plasma nitriding, plasma nitrocarburizing, plasma oxidizing, plasma carbonitriding and plasma carburizing. This takes place primarily in a vacuum chamber at a treatment pressure of 0.3 to 10 mbar.
  • the treatment temperature is between 400 - 600 ° C depending on the task.
  • Ammonia, nitrogen, methane and hydrogen are predominantly used as process gases.
  • Pressure, temperature, time and gas type form parameters when varying layers and desired surface hardness. Surface hardnesses of up to 1200 HV can be achieved on the desired surfaces, with a hardness depth of up to 1 mm being achieved.

Abstract

The invention relates to a temperature-controlled, rotating, rotational symmetric heat exchanger, particularly for the pressing mechanism, drying mechanism or smoothing mechanism of a machine for producing web-like products such as paper webs or plastic films. The heat exchanger can be temperature-controlled preferably with fluids or vaporous heat transfer media or with heating involving electrical means. The aim of the invention is to improve a heat exchanger of the aforementioned type as to achieve surface hardnesses of far greater than 400 - 450 HV and to minimize the chemical/mechanical corrosion even at heat transfer capacities > 80 kW/m. To this end, the heat exchanger is plamatized.

Description

PLASMATRIERTER WÄRMETAUSCHER PLASMATRATED HEAT EXCHANGER
Die Erfindung betrifft einen Wärmetauscher nach dem Oberbegriff des Anspruchs 1. Derartige Wärmetauscher werden zur Herstellung bzw. Veredelung von bahnartigen Produkten in der Industrie, vorwiegend in Kalandern, eingesetzt.The invention relates to a heat exchanger according to the preamble of claim 1. Such heat exchangers are used for the production or finishing of web-like products in industry, predominantly in calenders.
Die bei den neuen Multi-Nip-Kalanderwalzen geforderten Wärmeübertragungsleistungen und Oberflächentemperaturen belasten die bisher üblichen Kalan- derwalzenwerkstoffe wie Hartguss, Sphäroguss oder Chromguss über ihre Belastungsgrenzen hinaus. Schmiedestahl ist zzt. der Werkstoff, der diese Anforderungen erfüllt. Da jedoch ein adäquater Schmiedestahl nur bis Werkstoffhärten von 400-450 HV vergütet werden kann, ohne die Vorzüge von Schmiedestahl einzubüßen, werden diese Walzen entweder z. B. galvanisch oder thermisch oberflächenbeschichtet oder z. B. durch Induktivhärten oder Flammhärten randschichtgehärtet.The heat transfer rates and surface temperatures required for the new multi-nip calender rolls put the usual calender roll materials such as chilled cast iron, nodular cast iron or chrome cast iron beyond their load limits. Forged steel is currently. the material that meets these requirements. However, since an adequate forged steel can only be tempered up to material hardness of 400-450 HV without losing the advantages of forged steel, these rollers are either z. B. galvanically or thermally coated or z. B. surface hardened by induction hardening or flame hardening.
Die thermisch aufgebrachten Oberflächenbeschichtungen haben neben einer ungenügenden Prozesssicherheit den Nachteil einer relativ großen Porosität der Fertigschicht. Verschleißpartikel haben die Möglichkeit in diese Poren und die weniger harten Matrixbereiche einzudringen und diese dann "auszuwaschen". Randschichtgehärtete Schmiedestahlwalzen weisen neben einer unzureichenden Anlassbeständigkeit und damit verbundenen zu niedrigen Härte eine ungünstige, durch das Randschichthärten verursachte Eigenspannungsver- teilung auf. Hohe Zugspannungen im Bereich der Härteeinflusszone machen die Vorteile der guten mechanischen Eigenschaften von Schmiedestahl zunichte. Neue Streichmassen und Einsatzstoffe bei der Papierherstellung erfordern gesteigerte chemische und mechanische Korrosionsfestigkeit nicht nur des Walzenballens sondern der gesamten mit der Umwelt und der Warenbahn in Verbindung stehenden Walzenoberfläche. Aufgrund der enormen Wärmeübertragungsleistungen (> 80 kW/m), ständig steigende Wärmeübertragungstemperaturen sind auch die dem fluiden Wärmeträgern ausgesetzten Kontaktflächen einer immer größeren chemisch / mechanisch Korrosion ausgesetzt.In addition to insufficient process reliability, the thermally applied surface coatings have the disadvantage of a relatively large porosity of the finished layer. Wear particles have the ability to penetrate these pores and the less hard matrix areas and then "wash them out". Surface-hardened forged steel rollers, in addition to insufficient tempering resistance and the associated low hardness, also have an unfavorable residual stress distribution caused by surface-hardening. High tensile stresses in the area of the hardness zone negate the advantages of the good mechanical properties of forged steel. New coating slips and feedstocks in paper production require increased chemical and mechanical corrosion resistance not only of the roll barrel but also of the entire roll surface which is connected to the environment and the web. Due to the enormous heat transfer capacities (> 80 kW / m), constantly increasing heat transfer temperatures, the contact surfaces exposed to the fluid heat transfer media are exposed to ever greater chemical / mechanical corrosion.
Der Erfindung liegt die Aufgabe zugrunde, einen gattungsgemäßen Wärmetauscher so weiterzubilden, dass er die o. g. Nachteile nicht aufweist, insbesondere daß Oberflächenhärten weit über 400 - 450 HV erreicht werden, und dass die chemische/meschanische Korrossion auch bei Wärmeübertragungsleistungen > 80 kW/m minimiert wird..The invention has for its object to develop a generic heat exchanger so that he the above. Does not have disadvantages, in particular that surface hardnesses well in excess of 400-450 HV are achieved and that chemical / mechanical corrosion is minimized even with heat transfer rates> 80 kW / m.
Erfindungsgemäß werden die oben beschriebenen, vergüteten Schmiedestahl- wal∑en an den gewünschten Stellen plasmatriert. Der Ausdruck Plasmatrieren wird im Folgenden als Sammelausdruck für die Unterbegriffe Plasmanitrieren, Plasmanitrocarburieren, Plasmaoxidieren, Plasmacarbonitrieren und Plasma- carborieren verwendet. Dieses findet vorwiegend in einer Vakuumkammer bei einem Behandlungsdruck von 0,3 bis 10 mbar statt. Die Behandlungstemperatur liegt je nach Aufgabenstellung zwischen 400 - 600 °C. Als Prozessgase werden überwiegend Ammoniak, Stickstoff, Methan und Wasserstoff eingesetzt. Druck, Temperatur, Zeit und Gasart bilden Parameter bei der Variation von Schichten und gewünschten Oberflächenhärten. An den gewünschten Oberflächen können Oberflächenhärten von bis zu 1200 HV erreicht werden, wobei eine Härtetiefe von bis zu 1 mm realisiert wird. Neben dieser extremen Härte bilden diese Diffusions-Schichten keine für den Verschleißprozess schädliche Prorositätserhöhung. Die Prorosität des Substrates bleibt erhalten. Zusätzlich wird eine enorme Verbesserung gegenüber chemischer Korrosion erreicht. Eine Unterkorrosion, bekannt beim thermischen Spritzbeschichten oder auch Hartchrombeschichtungen ist beim Plasmatrieren nicht möglich. Die Verbindungsschicht an der Oberfläche passiviert die Oberfläche gegen Oxidationsan- griffe. Mikrorissbildungen, ebenfalls bekannt bei den o. g. Verfahren, findet hier ebenfalls nicht statt. According to the invention, the tempered forged steel rollers described above are plasma-coated at the desired locations. The term plasma mating is used in the following as a collective term for the sub-terms plasma nitriding, plasma nitrocarburizing, plasma oxidizing, plasma carbonitriding and plasma carburizing. This takes place primarily in a vacuum chamber at a treatment pressure of 0.3 to 10 mbar. The treatment temperature is between 400 - 600 ° C depending on the task. Ammonia, nitrogen, methane and hydrogen are predominantly used as process gases. Pressure, temperature, time and gas type form parameters when varying layers and desired surface hardness. Surface hardnesses of up to 1200 HV can be achieved on the desired surfaces, with a hardness depth of up to 1 mm being achieved. In addition to this extreme hardness, these diffusion layers do not form an increase in porosity that is harmful to the wear process. The substrate is preserved. In addition, an enormous improvement over chemical corrosion is achieved. Undercorrosion, known in the case of thermal spray coating or also hard chrome coating, is not possible in the case of plasma coating. The connection layer on the surface passivates the surface against oxidation attacks. Micro-cracking, also known from the above-mentioned processes, does not take place here either.

Claims

PATENTANSPRÜCHE
1. Temperierbarer, rotierbarer, rotationssymmetrischer Wärmetauscher, insbesondere für das Press-, Trocken- oder Glättwerk einer Maschine zur Herstellung von bahnartigen Produkten, wie Papierbahnen oder Kunststofffolien, der vorzugsweise mit fluiden bzw. dampfförmigen Wärmeträgern oder einer Beheizung auf dem elektrischen Wege, temperierbar ist, dadurch gekennzeichnet, dass der Wärmetauscher plasmatriert ist.1.Temperable, rotatable, rotationally symmetrical heat exchanger, in particular for the pressing, drying or smoothing unit of a machine for producing web-like products, such as paper webs or plastic films, which can preferably be tempered with fluid or vaporous heat carriers or heating by electrical means , characterized in that the heat exchanger is plasma-coated.
2. Wärmetauscher nach Anspruch 1 , dadurch gekennzeichnet, dass die Walzenzapfenoberfläche ganz oder teilweise plasmatriert ist.2. Heat exchanger according to claim 1, characterized in that the roll neck surface is completely or partially plasma-coated.
3. Wärmetauscher nach Anspruch 1 oder 2, dadurch gekennzeichnet, dass die Kontaktfläche des Wärmetauschers zum bahnartigen Produkt plasmatriert ist.3. Heat exchanger according to claim 1 or 2, characterized in that the contact surface of the heat exchanger is plasma-coated to the web-like product.
4. Wärmetauscher nach einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, dass die Ballenoberfläche des Wärmetauschers plasmatriert ist.4. Heat exchanger according to one of claims 1 to 3, characterized in that the bale surface of the heat exchanger is plasma-coated.
5. Wärmetauscher nach einem der Ansprüche 1 bis 4, dadurch gekennzeichnet, dass die Walzenoberfläche plasmatriert ist. 5. Heat exchanger according to one of claims 1 to 4, characterized in that the roller surface is plasma-coated.
6. Wärmetauscher nach einem der Ansprüche 1 oder 3, dadurch gekennzeichnet, dass heizmediumsberuhrten Oberflächen ganz oder teilweise plasmatriert sind.6. Heat exchanger according to one of claims 1 or 3, characterized in that surfaces which are in contact with the heating medium are completely or partially plasma-coated.
7. Wärmetauscher nach einem der Ansprüche 1 bis 6, dadurch gekennzeichnet, dass eine Verbindungsschicht an der Oberfläche ausgebildet ist.7. Heat exchanger according to one of claims 1 to 6, characterized in that a connecting layer is formed on the surface.
8. Wärmetauscher nach einem der Ansprüche 1 bis 6, dadurch gekennzeichnet, dass keine Verbindungsschicht an der Oberfläche ausgebildet ist.8. Heat exchanger according to one of claims 1 to 6, characterized in that no connection layer is formed on the surface.
9. Wärmetauscher nach einem der Ansprüche 1 bis 8, dadurch gekennzeichnet, dass die Unterkorrosion verhindert ist.9. Heat exchanger according to one of claims 1 to 8, characterized in that the under corrosion is prevented.
10. Wärmetauscher nach einem der Ansprüche 1 bis 9, da durch gekennzeichnet, dass die plasmatrierte Kalanderwalze bei einer Prozesstemperatur von -20 °C bis 500 °C einsetzbar ist. 10. Heat exchanger according to one of claims 1 to 9, characterized in that the plasma-coated calender roll can be used at a process temperature of -20 ° C to 500 ° C.
EP04710849A 2003-02-19 2004-02-13 Plasmatized heat exchanger Withdrawn EP1595025A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE10307107 2003-02-19
DE10307107 2003-02-19
PCT/EP2004/001340 WO2004074571A1 (en) 2003-02-19 2004-02-13 Plasmatized heat exchanger

Publications (1)

Publication Number Publication Date
EP1595025A1 true EP1595025A1 (en) 2005-11-16

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EP04710849A Withdrawn EP1595025A1 (en) 2003-02-19 2004-02-13 Plasmatized heat exchanger

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US (1) US20060144563A1 (en)
EP (1) EP1595025A1 (en)
JP (1) JP2006518013A (en)
CA (1) CA2516951A1 (en)
WO (1) WO2004074571A1 (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102006003386A1 (en) * 2006-01-24 2007-07-26 Reichel, Walter, Dipl.-Ing. Ion implantation unit for roller surfaces, comprises an ion source, an accelerator, a vacuum chamber and a deflection unit
JP5241455B2 (en) * 2008-12-02 2013-07-17 新日鐵住金株式会社 Carbonitriding member and method for producing carbonitriding member

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FI82094C (en) * 1989-02-16 1997-09-09 Valmet Corp Anvaendning av en legering av ett metallpulver och en carbid eller nitride innefattande belaeggningskomposition Foer en i en pappersmaskin anvaendbar yankeecylinder
JPH05304872A (en) * 1992-04-30 1993-11-19 Sanyo Electric Co Ltd Mixer-mounting structure of automatic noodle-making machine
US5707705A (en) * 1993-09-08 1998-01-13 Tulip Memory Systems, Inc. Titanium or titanium-alloy substrate for magnetic-recording media
US5499936A (en) * 1995-01-12 1996-03-19 Outboard Marine Corporation Monolithic metallic drive shafts which are resistant to corrosion and wear
DE19525863A1 (en) * 1995-07-15 1997-01-16 Ae Goetze Gmbh Mechanical seal for the tracks of caterpillars
DE19730449A1 (en) * 1997-07-16 1999-01-21 Mosca G Maschf Clamping device for strapping machines
US6755566B2 (en) * 2001-02-15 2004-06-29 Konrad Damasko Clockwork
US7465362B2 (en) * 2002-05-08 2008-12-16 Btu International, Inc. Plasma-assisted nitrogen surface-treatment
US6966954B2 (en) * 2002-10-24 2005-11-22 General Electric Comany Spall propagation properties of case-hardened M50 and M50NiL bearings

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2004074571A1 *

Also Published As

Publication number Publication date
WO2004074571A1 (en) 2004-09-02
US20060144563A1 (en) 2006-07-06
JP2006518013A (en) 2006-08-03
CA2516951A1 (en) 2004-09-02

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