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EP0311030A1 - Process for annealing metallic work pieces in a continuous furnace - Google Patents

Process for annealing metallic work pieces in a continuous furnace Download PDF

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Publication number
EP0311030A1
EP0311030A1 EP88116437A EP88116437A EP0311030A1 EP 0311030 A1 EP0311030 A1 EP 0311030A1 EP 88116437 A EP88116437 A EP 88116437A EP 88116437 A EP88116437 A EP 88116437A EP 0311030 A1 EP0311030 A1 EP 0311030A1
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EP
European Patent Office
Prior art keywords
annealing
hydrogen
protective gas
continuous
nitrogen
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Withdrawn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
EP88116437A
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German (de)
French (fr)
Inventor
Rüdiger Dr.-Ing. Conrad
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Linde GmbH
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Linde GmbH
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Publication of EP0311030A1 publication Critical patent/EP0311030A1/en
Withdrawn legal-status Critical Current

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    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21DMODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/74Methods of treatment in inert gas, controlled atmosphere, vacuum or pulverulent material
    • C21D1/76Adjusting the composition of the atmosphere
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21DMODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D9/00Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/52Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for wires; for strips ; for rods of unlimited length
    • C21D9/54Furnaces for treating strips or wire
    • C21D9/56Continuous furnaces for strip or wire
    • C21D9/561Continuous furnaces for strip or wire with a controlled atmosphere or vacuum
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21DMODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D9/00Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/52Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for wires; for strips ; for rods of unlimited length
    • C21D9/54Furnaces for treating strips or wire
    • C21D9/56Continuous furnaces for strip or wire
    • C21D9/562Details
    • C21D9/565Sealing arrangements

Definitions

  • the invention relates to a method for annealing metal parts in continuous furnaces under a protective gas atmosphere.
  • Annealing of metal parts is often carried out in a reducing protective gas atmosphere. It is generally known to carry out an annealing process with a protective gas atmosphere generated from ammonia. This atmosphere is generated by catalytic decomposition of ammonia (NH3) and contains 75 vol% hydrogen and 25 vol% nitrogen. With this protective gas and this protective gas production, it is possible to carry out high-quality and economically favorable annealing processes.
  • a protective gas atmosphere generated from ammonia. This atmosphere is generated by catalytic decomposition of ammonia (NH3) and contains 75 vol% hydrogen and 25 vol% nitrogen.
  • the object of the invention is now to provide an annealing process for continuous furnaces, which improves the economy of these furnaces with special attention to the problem of white dust.
  • the inlet and outlet openings of a continuous furnace are preceded by chambers which are filled with inert gas, e.g. Nitrogen.
  • inert gas e.g. Nitrogen
  • the upstream, rinsed lock chamber protects the furnace against the ingress of air. It is then possible to insert the one into the oven To reduce the amount of protective gas, pure hydrogen according to the invention. Due to the relatively high price of hydrogen (more than twice as expensive as nitrogen), this leads to an improvement in the economics of the process.
  • the figure shows a continuous furnace for recrystallizing bright annealing of stainless steel strips. It is known to operate such continuous furnaces with ammonia cracked gas or with a corresponding supply gas mixture of nitrogen and hydrogen, which is supplied through the protective gas supply opening 1. This is located between the annealing chamber 2 and the cooling zone 3 of the continuous furnace. Typical amounts of protective gas for operating such a furnace are in the range of about 100 to 300 m3 / h. According to the invention, an equal amount of pure hydrogen must now be supplied without using the upstream chambers 4. If upstream chambers are attached according to the sketch, the hydrogen protective gas supply can be reduced by 20 to 50%.
  • the use of hydrogen leads to a substantial extension of the intervals between two necessary cleaning of the cooling zone 3 and in particular the heat exchanger of the continuous furnace.
  • the remaining white dust formation is likely due to nitrogen entering the treatment zone from the prechamber and others Sources of nitrogen - small leaks.
  • the method according to the invention nevertheless provides a significant improvement in the economy of annealing in continuous furnaces.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Heat Treatment Of Strip Materials And Filament Materials (AREA)
  • Furnace Details (AREA)

Abstract

Annealing processes in which blanketing gas atmospheres are used which contain nitrogen and hydrogen, are known, for example cracked ammonia gas. During annealing in continuous furnaces, so-called white dust forms, which precipitates in the cooling zone and especially in the heat exchangers arranged therein, which causes the entire continuous annealing furnace to be closed down. The formation of white dust is considerably reduced by using pure hydrogen as the blanketing gas in annealing.

Description

Die Erfindung betrifft ein Verfahren zum Glühen von Metallteilen in Durchlauföfen unter einer Schutzgasatmospäre.The invention relates to a method for annealing metal parts in continuous furnaces under a protective gas atmosphere.

Glühen von Metallteilen, insbesondere Blankglühen, wird häufig in reduzierenden Schutzgasatmosphären durchgeführt. Allgemein bekannt ist dabei die Durchführung eines Glühverfahrens mit einer aus Ammoniak erzeugten Schutzgasatmosphäre. Diese Atmosphäre wird durch katalytische Spaltung von Ammoniak (NH₃) erzeugt und enthält 75 Vol-% Wasserstoff und 25 Vol-% Stickstoff. Mit diesem Schutzgas und dieser Schutzgasherstellung ist es möglich, qualitativ gute und wirtschaftlich günstige Glühverfahren durchzuführen.Annealing of metal parts, especially bright annealing, is often carried out in a reducing protective gas atmosphere. It is generally known to carry out an annealing process with a protective gas atmosphere generated from ammonia. This atmosphere is generated by catalytic decomposition of ammonia (NH₃) and contains 75 vol% hydrogen and 25 vol% nitrogen. With this protective gas and this protective gas production, it is possible to carry out high-quality and economically favorable annealing processes.

Aufgrund gesunkener Preise für angelieferte Gase sind aber bereits heute viele Wärmebehandlungsverfahren bekannt, bei denen Schutzgasatmosphären eingesetzt werden, die nicht in Gasgeneratoren vor Ort erzeugt sondern aus Liefergasen hergestellt werden. So ist auch bekannt, ein dem Ammoniakspaltgas entsprechendes Schutzgas mittels geliefertem reinem Wasserstoff und Stickstoff zu erzeugen. Aufgrund des getrennten Vorhandenseins von Stickstoff und Wasserstoff ist nun auch die Verwendung von anderen Schutzgaszusammensetzungen als die von Ammoniakspaltgas leicht möglich. Dabei bilden zwei grundlegende Gesichtspunkte den Hintergrund: Einerseits wird ein Schutzgasgemisch bei Verwendung hoher Stickstoffanteile kostengünstiger, wobei aber anderseits dem Schutzgas Eigenschaften, die auf den Wasserstoff zurückgehen, wie z.B. bessere Wärmeleitfähigkeit und daraus resultierend kürzere Aufheiz- und Abkühldauern im Ofen, verloren gehen. Diese Vorteile von Wasserstoff haben in speziellen Fällen, z.B. bei Glühbehandlungen in Haubenöfen (siehe z.B. DE-PS 31 05 064, insbesondere im Stand der Technik) dazu geführt, daß Schutzgas- atmosphären mit 100 % Wasserstoff verwendet werden.However, due to lower prices for supplied gases, many heat treatment processes are already known in which protective gas atmospheres are used, which are not generated in gas generators on site but are produced from supply gases. It’s like that known to generate a protective gas corresponding to the ammonia cracked gas by means of pure hydrogen and nitrogen supplied. Due to the separate presence of nitrogen and hydrogen, the use of protective gas compositions other than that of ammonia cracked gas is now easily possible. Two fundamental aspects form the background: On the one hand, a protective gas mixture becomes cheaper when using high nitrogen contents, but on the other hand properties of the protective gas that are due to the hydrogen, such as better thermal conductivity and the resulting shorter heating and cooling times in the furnace, are lost. In special cases, for example in annealing treatments in bell-type furnaces (see for example DE-PS 31 05 064, in particular in the prior art), these advantages of hydrogen have led to the use of protective gas atmospheres with 100% hydrogen.

Im Gegensatz dazu besteht in der Fachwelt das Urteil, daß bei Durchlauföfen, die wegen der zu spülenden Einlaß- und Auslaßoffnungen eine besonders große Schutzgasmenge benötigen, der Einsatz einer 100%-Wasserstoffatmosphäre aus Kostengründen nicht sinnvoll ist.In contrast, there is a judgment among experts that in continuous furnaces that require a particularly large amount of protective gas because of the inlet and outlet openings to be flushed, the use of a 100% hydrogen atmosphere is not sensible for reasons of cost.

Bei der Gestaltung eines Wärmebehandlungsverfahrens mit Stickstoff-Wasserstoff-Schutzgasgemischen ist neben den jetzt genannten Möglichkeiten und Gesichtspunkten noch ein der Fachwelt wohlbekanntes aber noch nicht voll­ständig aufgeklärtes Phänomen zu berücksichtigen. Es ensteht bei der Durchführung derartiger Glühverfahren mit Stickstoff-Wasserstoff-Atmosphären, wobei z.B. Stahlbleche oder Edelstahlbleche geglüht werden, eine als "weißer Staub" bezeichnete pulverförmige Substanz, die im wesentlichen wahrscheinlich aus Bornitriden und Boraminoverbindungen besteht. Diese Verbindungen lagern sich insbesondere im Kühlbereich von Durchlauföfen ab, da dort das Schutzgas mit Hilfe von Wärmetauschern abgekühlt wird, wobei diese Verbindungen aus dem Schutzgas desublimieren.When designing a heat treatment process with nitrogen-hydrogen-protective gas mixtures, in addition to the options and points of view that have just been mentioned, a phenomenon that is well-known but not yet fully understood by experts is to be taken into account. It arises when such annealing processes are carried out with nitrogen-hydrogen atmospheres, for example Steel sheets or stainless steel sheets are annealed, a powdery substance referred to as "white dust", which is likely to consist essentially of boron nitrides and boramino compounds. These compounds are deposited in particular in the cooling area of continuous furnaces, since the protective gas is cooled there with the aid of heat exchangers, and these compounds desublimate from the protective gas.

Die Bildung und Ablagerung des weißen Staubes insbesondere in den Wärmetauschern von Durchlauföfen führt zu einer schnellen und beträchtlichen Abnahme der Kühlleistung in den Kühlzonen der Öfen und somit insgesamt zu einer Verringerung des Durchsatzes an zu behandelndem metallischem Gut. Deshalb muß auch in mehr oder weniger regelmäßigen Abständen eine Reinigung der Wärmetauscher der Öfen durchgeführt werden, um ein Absinken der Kühlleistung auf nicht mehr tolerierbare Werte zu vermeiden. Dies bedeutet, daß aufgrund des weißen Staubes zusätzliche Stillstandszeiten insbesondere bei Durchlauföfen entstehen.The formation and deposition of the white dust, particularly in the heat exchangers of continuous furnaces, leads to a rapid and considerable decrease in the cooling capacity in the cooling zones of the furnaces and thus overall to a reduction in the throughput of metallic material to be treated. For this reason, the heat exchangers of the ovens must also be cleaned at more or less regular intervals in order to prevent the cooling capacity from dropping to unacceptable values. This means that due to the white dust, additional downtimes occur, particularly with continuous furnaces.

Die Aufgabe der Erfindung besteht nun darin, ein Glühverfahren für Durchlauföfen anzugeben, das die Wirtschaftlichkeit dieser Öfen unter besonderer Berücksichtigung des Problems des weißen Staubes verbessert.The object of the invention is now to provide an annealing process for continuous furnaces, which improves the economy of these furnaces with special attention to the problem of white dust.

Diese Aufgabe wird erfindungsgemäß gelöst, daß als Schutzgas reiner Wasserstoff verwendet wird.This object is achieved in that pure hydrogen is used as the protective gas.

Durch die Verwendung von reinem Wasserstoff wird die Entstehung von weißem Staub erheblich verringert.The use of pure hydrogen considerably reduces the generation of white dust.

Dadurch werden zwar kostenmäßige Nachteile von Wasserstoff gegenüber Stickstoff-Wasserstoff-Gemischen in Kauf genommen, es ergibt sich jedoch durch die Verringerung des weißen Staubes eine erhebliche Verlängerung der Zeit zwischen zwei Betriebsunterbrechungen. Der weiße Staub kann mit reiner Wasserstoffatmosphäre wahrscheinlich deshalb reduziert werden, da seine Entstehung auf die katalytische Bildung von Ammoniak, aus der normalerweise verwendeten Stickstoff-Wasserstoff-Atmosphäre und der anschließenden Weiterreaktion mit Bor aus dem behandelten metallischen Gut zurückgeht. Die Verwendung einer reinen H₂-Atmosphäre schließt daher die Bildung von Ammoniak und dessen Folgeprodukte aus. Somit wird mit einer verhältnismäßig einfachen technischen Maßnahme, die aber der allgemeinen Ansicht der Fachwelt zuwiderhandelt, ein schwerwiegendes Problem beim Glühen in Durchlauföfen beseitigt. Bei diskontinuierlich arbeitenden Wärmebehandlungsöfen ist dieses Problem von geringerer Relevanz, da derartige Anlagen entsprechend ihrer Konzeption sowieso zum Chargenwechsel heruntergefahren werden und somit eine Reinigung zwischen zwei Arbeitsgängen jederzeit möglich ist.Although this does accept the cost disadvantages of hydrogen compared to nitrogen-hydrogen mixtures, the reduction in white dust results in a considerable increase in the time between two business interruptions. The white dust can probably be reduced with a pure hydrogen atmosphere because its formation is due to the catalytic formation of ammonia, from the normally used nitrogen-hydrogen atmosphere and the subsequent further reaction with boron from the treated metallic material. The use of a pure H₂ atmosphere therefore excludes the formation of ammonia and its secondary products. Thus, a relatively simple technical measure, which is contrary to the general view of the professional world, eliminates a serious problem with annealing in continuous furnaces. This problem is of less relevance in the case of discontinuously operating heat treatment furnaces, since such systems are shut down to change batches anyway according to their design, and cleaning between two work steps is therefore possible at any time.

In einer vorteilhaften Ausgestaltungsmöglichkeit des erfindungsgemäßen Verfahrens werden der Eintritts- und der Ausstrittsöffnung eines Durchlaufofens Kammern vorgeschaltet, die mit Inertgas, z.B. Stickstoff, gespült werden.In an advantageous embodiment of the method according to the invention, the inlet and outlet openings of a continuous furnace are preceded by chambers which are filled with inert gas, e.g. Nitrogen.

Durch die vorgeschaltete, gespülte Schleusenkammer wird der Ofen gegen Eindringen von Luft abgesichert. Es ist dann möglich, die in den Ofen einzuführende Schutzgasmenge, erfindungsgemäß reiner Wasserstoff, zu reduzieren. Dies führt aufgrund des relativ hohen Preises von Wasserstoff (mehr als doppelt so teuer wie z.B. Stickstoff) zu einer Verbesserung der Wirtschaftlichkeit des Verfahrens.The upstream, rinsed lock chamber protects the furnace against the ingress of air. It is then possible to insert the one into the oven To reduce the amount of protective gas, pure hydrogen according to the invention. Due to the relatively high price of hydrogen (more than twice as expensive as nitrogen), this leads to an improvement in the economics of the process.

Im folgenden soll anhand der schematischen Zeichnung das erfindungsgemäße Verfahren näher erläutert werden.The method according to the invention will be explained in more detail below with the aid of the schematic drawing.

Die Figur zeigt einen Durchlaufofen zum rekristallisierenden Blankglühen von Edelstahlblechbändern. Es ist bekannt, derartige Durchlauföfen mit Ammoniakspaltgas oder mit einer entsprechenden Liefergasmischung aus Stickstoff und Wasserstoff zu betreiben, das durch die Schutzgaszuführungsöffnung 1 zugeführt wird. Diese befindet sich zwischen der Glühkammer 2 und der Kühlzone 3 des Durchlaufofens. Typische Schutzgasmengen zum Betrieb eines solchen Ofens liegen im Bereich von etwa 100 bis 300 m³/h. Entsprechend der Erfindung muß nun ohne Verwendung der vorgeschalteten Kammern 4 eine ebensolche Menge an reinem Wasserstoff zugeführt werden. Sind entsprechend der Skizze vorgeschaltete Kammern angebracht, so kann die Wasserstoffschutzgaszufuhr um 20 bis 50 % verringert werden.The figure shows a continuous furnace for recrystallizing bright annealing of stainless steel strips. It is known to operate such continuous furnaces with ammonia cracked gas or with a corresponding supply gas mixture of nitrogen and hydrogen, which is supplied through the protective gas supply opening 1. This is located between the annealing chamber 2 and the cooling zone 3 of the continuous furnace. Typical amounts of protective gas for operating such a furnace are in the range of about 100 to 300 m³ / h. According to the invention, an equal amount of pure hydrogen must now be supplied without using the upstream chambers 4. If upstream chambers are attached according to the sketch, the hydrogen protective gas supply can be reduced by 20 to 50%.

Die Verwendung von Wasserstoff führt zu einer wesentlichen Verlängerung der Intervalle twischen zwei notwendigen Reinigungen der Kühlzone 3 und insbesondere der Wärmetauscher des Durchlaufofens. Die noch verbleibende Bildung von weißem Staub ist wahrscheinlich auf aus der Vorkammer in die Behandlungszone eindringenden Stickstoff und auf andere Stickstoffquellen - kleine Lecks - zurückzuführen. Das erfindungsgemäße Verfahren liefert aber trotzdem eine wesentliche Verbesserung der Wirtschaftlichkeit des Glühens in Durchlauföfen.The use of hydrogen leads to a substantial extension of the intervals between two necessary cleaning of the cooling zone 3 and in particular the heat exchanger of the continuous furnace. The remaining white dust formation is likely due to nitrogen entering the treatment zone from the prechamber and others Sources of nitrogen - small leaks. The method according to the invention nevertheless provides a significant improvement in the economy of annealing in continuous furnaces.

Claims (2)

1. Verfahren zum Glühen von Metallteilen unter Schutzgas in Durchlauföfen, dadurch gekennzeichnet, daß als Schutzgas reiner Wasserstoff verwendet wird.1. Process for the annealing of metal parts under protective gas in continuous furnaces, characterized in that pure hydrogen is used as the protective gas. 2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß an der Eintritts- und der Austrittsöffnung des Durchlaufofens Kammern vorgeschaltet werden, die mit Inertgas, z.B. Stickstoff, gespült werden.2. The method according to claim 1, characterized in that at the inlet and the outlet opening of the continuous furnace chambers are connected upstream, which are filled with inert gas, e.g. Nitrogen.
EP88116437A 1987-10-07 1988-10-05 Process for annealing metallic work pieces in a continuous furnace Withdrawn EP0311030A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19873733884 DE3733884A1 (en) 1987-10-07 1987-10-07 METHOD FOR GLOWING METAL PARTS IN CONTINUOUS OVENS
DE3733884 1987-10-07

Publications (1)

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EP0311030A1 true EP0311030A1 (en) 1989-04-12

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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4966632A (en) * 1988-03-16 1990-10-30 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Process for the annealing treatment of metal strips
EP0714991A4 (en) * 1994-06-07 1999-04-28 Nisshin Steel Co Ltd Sealing device for outlet/inlet of controlled atmosphere heat treatment furnace
FR2809418A1 (en) * 2000-05-25 2001-11-30 Stein Heurtey METHOD FOR SECURING A HEAT TREATMENT ENCLOSURE OPERATING IN A CONTROLLED ATMOSPHERE
EP1408126A3 (en) * 1998-03-26 2004-07-21 JFE Steel Corporation Continuous heat treatment furnace
EP1679385A4 (en) * 2003-10-17 2007-05-30 Chugai Ro Kogyo Kaisha Ltd Method for controlling bright annealing furnace
WO2008000945A1 (en) * 2006-06-30 2008-01-03 Fives Stein Device for securing a furnace provided with a rapid cooling and heating system operating under controlled atmosphere.
US11486030B2 (en) 2018-05-23 2022-11-01 Molecule Works Inc. Process and apparatus for continuous production of porous structures

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4225982A1 (en) * 1992-08-06 1994-02-10 Linde Ag Process for the continuous annealing of metallic material under a hydrogen-rich protective gas

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Publication number Priority date Publication date Assignee Title
DD31283A (en) *
GB995883A (en) * 1962-07-05 1965-06-23 Davy & United Eng Co Ltd Continuous heat treatment of metal strip
DD243717A5 (en) * 1985-09-18 1987-03-11 Baumeister,Klaus,Dd METHOD FOR THE HEAT TREATMENT OF BAND OR WIRE WEAVING
US4696226A (en) * 1986-08-28 1987-09-29 Witmer Warner H Fluid barrier curtain system
EP0075438B1 (en) * 1981-09-19 1987-12-16 BOC Limited Heat treatment of metals

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DD31283A (en) *
GB995883A (en) * 1962-07-05 1965-06-23 Davy & United Eng Co Ltd Continuous heat treatment of metal strip
EP0075438B1 (en) * 1981-09-19 1987-12-16 BOC Limited Heat treatment of metals
DD243717A5 (en) * 1985-09-18 1987-03-11 Baumeister,Klaus,Dd METHOD FOR THE HEAT TREATMENT OF BAND OR WIRE WEAVING
US4696226A (en) * 1986-08-28 1987-09-29 Witmer Warner H Fluid barrier curtain system

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STAHL UND EISEN *
STEEL IN THE USSR *

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4966632A (en) * 1988-03-16 1990-10-30 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Process for the annealing treatment of metal strips
EP0714991A4 (en) * 1994-06-07 1999-04-28 Nisshin Steel Co Ltd Sealing device for outlet/inlet of controlled atmosphere heat treatment furnace
EP1408126A3 (en) * 1998-03-26 2004-07-21 JFE Steel Corporation Continuous heat treatment furnace
FR2809418A1 (en) * 2000-05-25 2001-11-30 Stein Heurtey METHOD FOR SECURING A HEAT TREATMENT ENCLOSURE OPERATING IN A CONTROLLED ATMOSPHERE
EP1160342A1 (en) * 2000-05-25 2001-12-05 Stein Heurtey Method for securing a controlled atmosphere heat treating chamber
EP1679385A4 (en) * 2003-10-17 2007-05-30 Chugai Ro Kogyo Kaisha Ltd Method for controlling bright annealing furnace
WO2008000945A1 (en) * 2006-06-30 2008-01-03 Fives Stein Device for securing a furnace provided with a rapid cooling and heating system operating under controlled atmosphere.
FR2903122A1 (en) * 2006-06-30 2008-01-04 Stein Heurtey DEVICE FOR SECURING AN OVEN EQUIPPED WITH FAST HEATING AND COOLING OPERATING UNDER CONTROLLED ATMOSPHERE.
JP2009541598A (en) * 2006-06-30 2009-11-26 ファイブス シュタイン Safety system for furnaces with rapid heating and cooling processes in a controlled atmosphere
EA012867B1 (en) * 2006-06-30 2009-12-30 Фив Стэн Device for securing a furnace provided with a rapid cooling and heating system operating under controlled atmosphere
CN101466852B (en) * 2006-06-30 2010-08-25 法孚斯坦因公司 Safety device for furnaces operating under controlled atmosphere and equipped with rapid heating and cooling sections
US11486030B2 (en) 2018-05-23 2022-11-01 Molecule Works Inc. Process and apparatus for continuous production of porous structures

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