EP0313888B1 - Method for the heat treatment of metallic work pieces - Google Patents

Method for the heat treatment of metallic work pieces Download PDF

Info

Publication number
EP0313888B1
EP0313888B1 EP19880116477 EP88116477A EP0313888B1 EP 0313888 B1 EP0313888 B1 EP 0313888B1 EP 19880116477 EP19880116477 EP 19880116477 EP 88116477 A EP88116477 A EP 88116477A EP 0313888 B1 EP0313888 B1 EP 0313888B1
Authority
EP
European Patent Office
Prior art keywords
cooling gas
helium
mpa
hydrogen
heat treatment
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP19880116477
Other languages
German (de)
French (fr)
Other versions
EP0313888A1 (en
EP0313888B2 (en
Inventor
Paul Dipl.-Ing. Heilmann
Friedrich Dipl.Phys.Dr. Preisser
Rolf Schuster
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.)
ALD Vacuum Technologies GmbH
Original Assignee
Leybold Durferrit GmbH
ALD Vacuum Technologies 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
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=6339263&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=EP0313888(B1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Leybold Durferrit GmbH, ALD Vacuum Technologies GmbH filed Critical Leybold Durferrit GmbH
Priority to AT88116477T priority Critical patent/ATE65801T1/en
Publication of EP0313888A1 publication Critical patent/EP0313888A1/en
Publication of EP0313888B1 publication Critical patent/EP0313888B1/en
Application granted granted Critical
Publication of EP0313888B2 publication Critical patent/EP0313888B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING 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
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/74—Methods of treatment in inert gas, controlled atmosphere, vacuum or pulverulent material
    • C21D1/767—Methods of treatment in inert gas, controlled atmosphere, vacuum or pulverulent material with forced gas circulation; Reheating thereof
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING 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
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/56—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering characterised by the quenching agents
    • C21D1/613—Gases; Liquefied or solidified normally gaseous material
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING 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
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/74—Methods of treatment in inert gas, controlled atmosphere, vacuum or pulverulent material
    • C21D1/773—Methods of treatment in inert gas, controlled atmosphere, vacuum or pulverulent material under reduced pressure or vacuum
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B5/00—Muffle furnaces; Retort furnaces; Other furnaces in which the charge is held completely isolated
    • F27B5/06—Details, accessories, or equipment peculiar to furnaces of these types
    • F27B5/16—Arrangements of air or gas supply devices
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B5/00—Muffle furnaces; Retort furnaces; Other furnaces in which the charge is held completely isolated
    • F27B5/06—Details, accessories, or equipment peculiar to furnaces of these types
    • F27B5/16—Arrangements of air or gas supply devices
    • F27B2005/161—Gas inflow or outflow

Definitions

  • the invention relates to a method for the heat treatment of metallic workpieces in a vacuum furnace by heating the workpieces and then quenching them in a cooling gas under excess pressure and cooling gas circulation.
  • This object is achieved in that helium, hydrogen, mixtures of helium and hydrogen or mixtures of helium and / or hydrogen with up to 30 vol% inert gas are used as cooling gas, that the cooling gas pressure "p" in the furnace is quenched to values between 1 and 4 MPa is set, and that the cooling gas velocity "v” is selected so that the product pv is between 10 and 250 m - MPa - sec- 1 .
  • Helium or helium mixtures with up to 30% by volume of hydrogen and / or inert gases are preferably used as the cooling gas.
  • the cooling gas velocity "V" refers to the exit from the cooling gas distribution pipes.
  • the steel parts are heated in a vacuum oven customary for this purpose.
  • the furnace is advantageously flooded with the helium or hydrogen gas at the start of the heating at about 2 MPa pressure and the gas is circulated with a fan.
  • This has the advantage that the heat is transferred to the steel parts not by radiation but by convection, which results in a uniform heating of the batch and a considerable reduction in the heating time.
  • the gas is removed from the furnace and further heated under vacuum. In this temperature range, radiant heating is very effective and a protective gas is not necessary to heat the batches.
  • the furnace is flooded with cold cooling gas up to 4 MPa overpressure to cool the batch.
  • the cooling gas is circulated with the aid of a fan, cooled down via a heat exchanger after leaving the furnace interior and fed back to the batch. This circulation continues until the batch has cooled.
  • the gas speed is adjusted with the help of the fan so that the product p. v between 10 and 250 m - MPa. sec -1 lies

Abstract

A process for heat treatment of metallic workpieces by heating in a vacuum furnace followed by quenching in a coolant gas under above-atmospheric pressure and with coolant-gas circulation.

Description

Die Erfindung betrifft ein Verfahren zur Wärmebehandlung metallischer Werkstücke in einem Vakuumofen durch Aufheizen der Werkstücke und anschließendes Abschrecken in einem Kühlgas unter Überdruck und Kühlgasumwälzung.The invention relates to a method for the heat treatment of metallic workpieces in a vacuum furnace by heating the workpieces and then quenching them in a cooling gas under excess pressure and cooling gas circulation.

Zum Härten metallischer Werkstücke, insbesondere Werkzeuge, werden diese in einem Ofen auf die Austenitisierungstemperatur des Werkstoffs erhitzt und dann abgeschreckt. Je nach Werkstoffart und gewünschter mechanischer Eigenschaften sind zum Abschrecken Bäder aus Wasser, Öl oder geschmolzenen Salzen erforderlich. Teile aus Schnellarbeitsstählen und anderen hocheegierten Werkstoffen können auch in Inertgasen abgeschreckt werden, wenn diese kontinuierlich gekühlt und umgewälzt werden.To harden metallic workpieces, in particular tools, they are heated in an oven to the austenitizing temperature of the material and then quenched. Depending on the type of material and the desired mechanical properties, baths of water, oil or molten salts are required for quenching. Parts made of high-speed steel and other highly alloyed materials can also be quenched in inert gases if they are continuously cooled and circulated.

In der DE-PS 28 39 807 und der DE-PS 28 44 343 werden Vakuumöfen beschrieben, in denen zum Abschrecken Kühlgase mit hoher Gasgeschwindigkeit und mit Drücken bis zu 0,6 MPa (6 bar) über die aufgeheizten Werkstückchargen und anschließend über Wärmetauscher geleitet werden. Die erforderlichen hohen Kühlgasgeschwindigkeiten erreicht man mit Hilfe von Düsen oder Ventilatoren. Höhere Abschreckgeschwindigkeiten kann man im Prinzip durch Erhöhung des Kühlgasdrucks erzielen, doch erreicht man bei den derzeit verwendeten Kühlgasen (z. B. Stickstoff, Argon) nur einen Überdruck bis zu etwa 0,6 MPa. Die Anwendung höherer Drücke wird durch die Motorleistung begrenzt, die zur Umwälzung der komprimierten Gase erforderlich ist. Bei Verwendung von Stickstoff als Kühlgas mit 0,6 MPa Überdruck beträgt die erforderliche Motorenleistung bei einem Ventilator bereits über 100 kW. Motoren mit höheren Leistungen sind aber sehr voluminös, teuer und für einen Einbau in einen Vakuumofen normalerweise nicht geeignet.In DE-PS 28 39 807 and DE-PS 28 44 343 vacuum furnaces are described in which, for quenching, cooling gases are passed at high gas velocity and with pressures of up to 0.6 MPa (6 bar) over the heated workpiece batches and then over heat exchangers will. The required high cooling gas speeds are achieved with the help of nozzles or fans. In principle, higher quenching speeds can be achieved by increasing the cooling gas pressure, but the cooling gases currently used (e.g. nitrogen, argon) only achieve an overpressure of up to about 0.6 MPa. The use of higher pressures is limited by the engine power required to circulate the compressed gases. When using nitrogen as the cooling gas with 0.6 MPa overpressure, the required motor power for a fan is already over 100 kW. However, motors with higher outputs are very voluminous, expensive and usually not suitable for installation in a vacuum furnace.

Durch diese technisch bedingte Begrenzung der Kühlgasumwälzung und des Kühlgasdrucks war es bisher nicht möglich, höhere Abschreckintensitäten mit Kühlgasen zu erreichen, so daß das Abschreckverfahren mit Kühlgasen auf spezielle Werkstoffe beschränkt ist.Due to this technical limitation of the cooling gas circulation and the cooling gas pressure, it has so far not been possible to achieve higher quenching intensities with cooling gases, so that the quenching process with cooling gases is restricted to special materials.

Es war Aufgabe der vorliegenden Erfindung, ein Verfahren zur Wärmebehandlung metallischer Werkstücke in einem Vakuumofen durch Aufheizen der Werkstücke und anschließendes Abschrecken in einem Kühlgas unter Überdruck und Kühlgasumwälzung zu entwickeln, mit dem eine höhere Abschreckintensitäterzielbarist, ohne die Motorenleistung fürdie Kühlgasumwälzung erhöhen zu müssen.It was an object of the present invention to develop a method for the heat treatment of metallic workpieces in a vacuum furnace by heating the workpieces and then quenching in a cooling gas under excess pressure and cooling gas circulation, with which a higher quenching intensity can be achieved without having to increase the engine output for the cooling gas circulation.

Diese Aufgabe wird erfindungsgemäß dadurch gelöst, daß als Kühlgas Helium, Wasserstoff, Gemische aus Helium und Wasserstoff oder Gemische aus Helium und/oder Wasserstoff mit bis zu 30 Vol% Inertgas verwendet werden, daß der Kühlgasdruck "p" im Ofen bei derAbschreckung auf Werte zwischen 1 und 4 MPa eingestellt wird, und daß die Kühlgasgeschwindigkeit "v" so gewählt wird, daß das Produkt p.v zwischen 10 und 250 m - MPa - sec-1 liegt.This object is achieved in that helium, hydrogen, mixtures of helium and hydrogen or mixtures of helium and / or hydrogen with up to 30 vol% inert gas are used as cooling gas, that the cooling gas pressure "p" in the furnace is quenched to values between 1 and 4 MPa is set, and that the cooling gas velocity "v" is selected so that the product pv is between 10 and 250 m - MPa - sec- 1 .

Vorzugsweise verwendet man als Kühlgas Helium oder Heliumgemische mit bis zu 30 Vol% Wasserstoff und/oder Inertgasen.Helium or helium mixtures with up to 30% by volume of hydrogen and / or inert gases are preferably used as the cooling gas.

Als günstig hat es sich erwiesen, im Ofen einen Kühlgasdruckzwischen 1,4 und 3,0 MPa einzustellen und die Kühlgasumwälzung mit einem Ventilator vorzunehmen.It has proven to be advantageous to set a cooling gas pressure between 1.4 and 3.0 MPa in the furnace and to carry out the cooling gas circulation with a fan.

Die Kühlgasgeschwindigkeit "V" bezieht sich auf den Austritt aus den Kühlgasverteilungsrohren.The cooling gas velocity "V" refers to the exit from the cooling gas distribution pipes.

Es hat sich überraschenderweise erwiesen, daß bei Verwendung von Helium und/oder Wasserstoff bzw. deren Gemische mit bis zu 30 Vol% Inertgas, wie z. B. Stickstoff, als Kühlgas in den entsprechenden Öfen Drücke bis zu 4 MPa eingestellt werden können, ohne daß die Motorleistung der verwendeten Ventilatoren erhöht werden müssen. Dadurch wird die Kühlwirkung der Gase derart verstärkt, daß ein wesentlich breiteres Spektrum von Stählen gehärtet werden kann, auch solche Stahlsorten, die man bisher in einem Ölbad abschrecken musste. Diese Hochdruck-Gasabschreckung hat gegenüber flüssigen Abschreckmedien verfahrenstechnische und wirtschaftliche Vorteile. Außerdem ist sie umweltfreundlicher.It has surprisingly been found that when using helium and / or hydrogen or mixtures thereof with up to 30 vol% inert gas, such as. B. nitrogen, as cooling gas in the corresponding furnaces, pressures up to 4 MPa can be set without the motor power of the fans used having to be increased. This increases the cooling effect of the gases in such a way that a much broader range of steels can be hardened, including those types of steel that previously had to be quenched in an oil bath. This high-pressure gas quenching has procedural and economic advantages over liquid quenching media. It is also more environmentally friendly.

Bei der praktischen Ausführung dieses Verfahrens werden die Stahlteile in einem für diesen Zweck üblichen Vakuumofen aufgeheizt. Dabei flutet man den Ofen vorteilhafterweise mit dem Helium- bzw. Wasserstoffgas bereits zu Beginn der Aufheizung mit etwa 2 MPa Druck und wälzt das Gas mit einem Ventilator um. Das hat den Vorteil, daß die Wärmeübertragung auf die Stahlteile nicht durch Strahlung sondern durch Konvektion erfolgt, was ein gleichmäßiges Aufheizen der Charge und eine beträchtliche Verkürzung der Aufheizzeit zur Folge hat. Oberhalb 750°C wird das Gas aus dem Ofen entfernt und unter Vakuum weitererhitzt In diesem Temperaturbereich ist die Strahlungserwärmung sehr wirksam und ein Schutzgas zur Erwärmung der Chargen nicht notwendig. Nach Erreichen der jeweiligen Austenitisierungtemperatur, die zwischen 800 und 1300°C liegen kann, wird zum Abkühlen der Charge der Ofen mit kaltem Kühlgas bis zu 4 MPa Überdruck geflutet. Das Kühlgas wird mit Hilfe eines Ventilators umgewälzt, nach Verlassen des Ofeninnenraums über einen Wärmetauscher abgekühlt und erneut der Charge zugeleitet. Diese Umwälzung erfolgt solange, bis die Charge abgekühlt ist. Die Gasgeschwindigkeit wird dabei mit Hilfe des Ventilators so eingestellt, daß das Produkt p . v zwischen 10 und 250 m - MPa . sec-1 liegtIn the practical implementation of this method, the steel parts are heated in a vacuum oven customary for this purpose. The furnace is advantageously flooded with the helium or hydrogen gas at the start of the heating at about 2 MPa pressure and the gas is circulated with a fan. This has the advantage that the heat is transferred to the steel parts not by radiation but by convection, which results in a uniform heating of the batch and a considerable reduction in the heating time. Above 750 ° C, the gas is removed from the furnace and further heated under vacuum. In this temperature range, radiant heating is very effective and a protective gas is not necessary to heat the batches. After reaching the respective austenitizing temperature, which can be between 800 and 1300 ° C, the furnace is flooded with cold cooling gas up to 4 MPa overpressure to cool the batch. The cooling gas is circulated with the aid of a fan, cooled down via a heat exchanger after leaving the furnace interior and fed back to the batch. This circulation continues until the batch has cooled. The gas speed is adjusted with the help of the fan so that the product p. v between 10 and 250 m - MPa. sec -1 lies

Folgendes Beispiel soll das erfindungsgemäße Verfahren näher erläutern :

  • Ein Bauteil mit ca. 10 mm Durchmesser aus dem niedriglegierten Stahl 100 Cr6 wird in einem Vakuumofen auf die Austenitisierungstemperatur von ca. 850°C erwärmt. Nach Erreichen dieser Temperatur wird der Ofen mit Helium bis zu einem Überdruck von 1,6 MPa geflutet, wobei bei einer Gasgeschwindigkeit von 65 m . sec-1 in 16 sec die Probe auf 400°C heruntergekühlt war, was der Abkühlgeschwindigkeit in einem Ölbad entspricht. Man erhält einen martensitischen Gefügezustand mit einer Härte von 64 HRC. Mit den bisher bekannten Gasabschreckungsverfahren läßt sich der Stahl 100 6Cr nicht härten.
The following example is intended to explain the process according to the invention in more detail:
  • A component with a diameter of approx. 10 mm from which never drig alloyed steel 100 Cr6 is heated in a vacuum furnace to the austenitizing temperature of approx. 850 ° C. After reaching this temperature, the furnace is flooded with helium up to an excess pressure of 1.6 MPa, with a gas velocity of 65 m. sec -1 in 16 sec the sample was cooled down to 400 ° C, which corresponds to the cooling rate in an oil bath. A martensitic structure with a hardness of 64 HRC is obtained. With the gas quenching processes known to date, the steel 100 6Cr cannot be hardened.

Claims (4)

1. A process for the heat treatment of metallic workpieces in a vacuum furnace by heating up the workpieces and subsequently chilling them in a cooling gas under excess pressure and with circulation of the cooling gas, characterised in that the cooling gas used is helium, hydrogen, mixtures of helium and hydrogen or mixtures of helium and/or hydrogen with up to 30 vol% of inert gas, in that the cooling gas pressure "p" in the furnace during chilling is adjusted to values from 1 to 4 MPa and in that the cooling gas velocity "V" is chosen so that the product p . v is from 10 to 250 m . MPa . sec-1.
2. A process according to claim 1, characterised in that the cooling gas used is helium or mixtures of helium with up to 30 vol% of hydrogen and/or inert gases.
3. A process according to claims 1 and 2, characterised in that a cooling gas pressure of from 1.4 to 3.0 MPa is adjusted in the furnace during the chilling stage.
4. A process according to claims 1 to 3, characterised in that circulation of the cooling gas is carried out with a ventilator.
EP88116477A 1987-10-28 1988-10-05 Method for hardening of work pieces of steel Expired - Lifetime EP0313888B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT88116477T ATE65801T1 (en) 1987-10-28 1988-10-05 METHOD OF HEAT TREATMENT OF METALLIC WORKPIECES.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3736501 1987-10-28
DE3736501A DE3736501C1 (en) 1987-10-28 1987-10-28 Process for the heat treatment of metallic workpieces

Publications (3)

Publication Number Publication Date
EP0313888A1 EP0313888A1 (en) 1989-05-03
EP0313888B1 true EP0313888B1 (en) 1991-07-31
EP0313888B2 EP0313888B2 (en) 1998-06-17

Family

ID=6339263

Family Applications (1)

Application Number Title Priority Date Filing Date
EP88116477A Expired - Lifetime EP0313888B2 (en) 1987-10-28 1988-10-05 Method for hardening of work pieces of steel

Country Status (28)

Country Link
US (1) US4867808A (en)
EP (1) EP0313888B2 (en)
JP (1) JP3068135B2 (en)
CN (1) CN1015066B (en)
AT (1) ATE65801T1 (en)
AU (1) AU606473B2 (en)
BG (1) BG49828A3 (en)
BR (1) BR8805492A (en)
CA (1) CA1308631C (en)
CS (1) CS274632B2 (en)
DD (1) DD283421A5 (en)
DE (2) DE3736501C1 (en)
DK (1) DK167497B1 (en)
ES (1) ES2023993T5 (en)
FI (1) FI86560C (en)
HR (1) HRP920581B1 (en)
HU (1) HU204102B (en)
IL (1) IL87762A (en)
MX (1) MX169690B (en)
NO (1) NO169244C (en)
PL (1) PL159767B1 (en)
PT (1) PT88896A (en)
RO (1) RO110067B1 (en)
RU (1) RU1813104C (en)
SI (1) SI8811937A8 (en)
UA (1) UA13002A (en)
YU (1) YU46574B (en)
ZA (1) ZA886853B (en)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0451050A1 (en) * 1990-04-04 1991-10-09 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Process and equipment for thermal treatment with gas quenching
FR2660744A1 (en) * 1990-04-04 1991-10-11 Air Liquide Bell oven
EP0495151A1 (en) * 1991-01-15 1992-07-22 Linde Aktiengesellschaft Method of heat treating in vacuum furnaces
EP0562250A1 (en) * 1992-03-17 1993-09-29 Joachim Dr.-Ing. Wünning Process and device for quenching of metal pieces
EP0869189A1 (en) * 1997-03-11 1998-10-07 Linde Aktiengesellschaft Process for gas quenching metallic workpieces
US6216358B1 (en) 1998-05-29 2001-04-17 Etudes Et Constructions Mecaniques Gas-quenching cell
DE10030046C1 (en) * 2000-06-19 2001-09-13 Ald Vacuum Techn Ag Determining cooling action of a flowing gas atmosphere on a workpiece comprises using a measuring body arranged in a fixed position outside of the workpiece and heated to a prescribed starting temperature using a heater
US6428742B1 (en) 1999-09-24 2002-08-06 Ispen International Gmbh Method for heat-treating metallic workpieces

Families Citing this family (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3819803C1 (en) * 1988-06-10 1989-12-14 Ulrich 5810 Witten De Wingens
DE3828134A1 (en) * 1988-08-18 1990-02-22 Linde Ag METHOD FOR THE HEAT TREATMENT OF WORKPIECES
US5173124A (en) * 1990-06-18 1992-12-22 Air Products And Chemicals, Inc. Rapid gas quenching process
DE4132712C2 (en) * 1991-10-01 1995-06-29 Ipsen Ind Int Gmbh Vacuum furnace for plasma carburizing metallic workpieces
US5478985A (en) * 1993-09-20 1995-12-26 Surface Combustion, Inc. Heat treat furnace with multi-bar high convective gas quench
DE4419332A1 (en) * 1994-06-02 1995-12-14 Wuenning Joachim Industrial burner with low NO¶x¶ emissions
US5524020A (en) * 1994-08-23 1996-06-04 Grier-Jhawar-Mercer, Inc. Vacuum furnace with movable hot zone
AT405190B (en) * 1996-03-29 1999-06-25 Ald Aichelin Ges M B H METHOD AND DEVICE FOR HEAT TREATING METAL WORKPIECES
DE69723608T3 (en) * 1996-04-26 2010-07-01 Nippon Steel Corp. Primary cooling process for continuous annealing of steel strip
US5934871A (en) * 1997-07-24 1999-08-10 Murphy; Donald G. Method and apparatus for supplying a anti-oxidizing gas to and simultaneously cooling a shaft and a fan in a heat treatment chamber
DE19824574A1 (en) * 1998-06-02 1999-12-09 Linde Ag Method and device for effective cooling of material to be treated
DE19920297A1 (en) * 1999-05-03 2000-11-09 Linde Tech Gase Gmbh Process for the heat treatment of metallic workpieces
FR2801059B1 (en) * 1999-11-17 2002-01-25 Etudes Const Mecaniques LOW PRESSURE CEMENTING QUENCHING PROCESS
DE10044362C2 (en) * 2000-09-08 2002-09-12 Ald Vacuum Techn Ag Process and furnace system for tempering a batch of steel workpieces
US20020104589A1 (en) * 2000-12-04 2002-08-08 Van Den Sype Jaak Process and apparatus for high pressure gas quenching in an atmospheric furnace
DE10108057A1 (en) * 2001-02-20 2002-08-22 Linde Ag Process for quenching metallic workpieces
DE10109565B4 (en) 2001-02-28 2005-10-20 Vacuheat Gmbh Method and device for partial thermochemical vacuum treatment of metallic workpieces
FR2835907B1 (en) * 2002-02-12 2004-09-17 Air Liquide GAS QUENCHING INSTALLATION AND CORRESPONDING QUENCHING METHOD
KR100591355B1 (en) * 2002-03-25 2006-06-19 히로히사 타니구치 Hot gas quenching devices and hot gas heat treating method
WO2005123970A1 (en) * 2004-06-15 2005-12-29 Narasimhan Gopinath A process and device for hardening metal parts
PL202005B1 (en) * 2004-11-19 2009-05-29 Politechnika & Lstrok Odzka In Hardening heater with closed hydrogen circuit
DE102005045783A1 (en) * 2005-09-23 2007-03-29 Sistem Teknik Endustriyel Elektronik Sistemler Sanayi Ve Ticaret Ltd. Sirketi Single-chamber vacuum furnace with hydrogen quenching
CN101880760A (en) * 2010-07-09 2010-11-10 中国第一汽车集团公司 Vacuum isothermal heat treatment process of large die-casting mould
WO2013096646A1 (en) 2011-12-20 2013-06-27 Eclipse, Inc. METHOD AND APPARATUS FOR A DUAL MODE BURNER YIELDING LOW NOx EMISSION
CN105695716A (en) * 2016-01-29 2016-06-22 柳州市安龙机械设备有限公司 Heat treatment method for hard alloy cutter

Family Cites Families (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1132171B (en) * 1960-06-24 1962-06-28 Heraeus Gmbh W C Process for annealing, melting or casting metals in a container under vacuum and cooling by means of protective gas, as well as device for carrying out this process
DE1919493C3 (en) * 1969-04-17 1980-05-08 Ipsen Industries International Gmbh, 4190 Kleve Atmospheric vacuum furnace
US4030712A (en) * 1975-02-05 1977-06-21 Alco Standard Corporation Method and apparatus for circulating a heat treating gas
US4167426A (en) * 1978-04-20 1979-09-11 Allegheny Ludlum Industries, Inc. Method for annealing silicon steel
DE2839807C2 (en) * 1978-09-13 1986-04-17 Degussa Ag, 6000 Frankfurt Vacuum furnace with gas cooling device
DE2844843C2 (en) * 1978-10-14 1985-09-12 Ipsen Industries International Gmbh, 4190 Kleve Industrial furnace for the heat treatment of metallic workpieces
US4302256A (en) * 1979-11-16 1981-11-24 Chromalloy American Corporation Method of improving mechanical properties of alloy parts
GB2052030B (en) * 1980-04-28 1984-02-08 Gen Electric Construction of special atmosphere furnace
JPS58147514A (en) * 1982-02-24 1983-09-02 Ishikawajima Harima Heavy Ind Co Ltd Method for cooling heat treated material with gas
US4462577A (en) * 1982-12-16 1984-07-31 C.I. Hayes Inc. Apparatus for gas cooling work parts under high pressure in a continuous heat treating vacuum furnace
AT395321B (en) * 1983-07-05 1992-11-25 Ebner Ind Ofenbau METHOD FOR COOLING CHARGES IN DISCONTINUOUSLY WORKING INDUSTRIAL OVENS, ESPECIALLY STEEL WIRE OR TAPE BANDS IN DOME GLUES
JPS60187620A (en) * 1984-03-06 1985-09-25 Daido Steel Co Ltd Vacuum furnace
DE3416902A1 (en) * 1984-05-08 1985-11-14 Schmetz Industrieofenbau und Vakuum-Hartlöttechnik KG, 5750 Menden METHOD AND VACUUM OVEN FOR HEAT TREATING A BATCH
JPS60262913A (en) * 1984-06-11 1985-12-26 Ishikawajima Harima Heavy Ind Co Ltd Method for introducing gas in forced-convection cooling
DE3736502C1 (en) * 1987-10-28 1988-06-09 Degussa Vacuum furnace for the heat treatment of metallic workpieces

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE1006163A4 (en) * 1990-04-04 1994-05-31 Air Liquide Method for heat treatment of metal objects in protective atmosphere.
FR2660669A1 (en) * 1990-04-04 1991-10-11 Air Liquide METHOD AND INSTALLATION FOR HEAT TREATMENT OF OBJECTS WITH TEMPERING IN GASEOUS MEDIA.
FR2660744A1 (en) * 1990-04-04 1991-10-11 Air Liquide Bell oven
EP0451050A1 (en) * 1990-04-04 1991-10-09 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Process and equipment for thermal treatment with gas quenching
EP0495151A1 (en) * 1991-01-15 1992-07-22 Linde Aktiengesellschaft Method of heat treating in vacuum furnaces
US5452882A (en) * 1992-03-17 1995-09-26 Wunning; Joachim Apparatus for quenching metallic ring-shaped workpieces
EP0562250A1 (en) * 1992-03-17 1993-09-29 Joachim Dr.-Ing. Wünning Process and device for quenching of metal pieces
EP0869189A1 (en) * 1997-03-11 1998-10-07 Linde Aktiengesellschaft Process for gas quenching metallic workpieces
US6216358B1 (en) 1998-05-29 2001-04-17 Etudes Et Constructions Mecaniques Gas-quenching cell
US6428742B1 (en) 1999-09-24 2002-08-06 Ispen International Gmbh Method for heat-treating metallic workpieces
DE10030046C1 (en) * 2000-06-19 2001-09-13 Ald Vacuum Techn Ag Determining cooling action of a flowing gas atmosphere on a workpiece comprises using a measuring body arranged in a fixed position outside of the workpiece and heated to a prescribed starting temperature using a heater
EP1167548A2 (en) * 2000-06-19 2002-01-02 ALD Vacuum Technologies AG Process and device for determining the cooling effect of a circulating gas atmosphere on workpieces
US6554922B2 (en) 2000-06-19 2003-04-29 Ald Vacuum Technologies Ag Method and apparatus for determining the cooling action of a flowing gas atmosphere on workpieces

Also Published As

Publication number Publication date
HRP920581B1 (en) 1997-10-31
PL275471A1 (en) 1989-05-02
MX169690B (en) 1993-07-19
IL87762A (en) 1993-01-31
EP0313888A1 (en) 1989-05-03
NO884389L (en) 1989-05-02
FI884513A0 (en) 1988-09-30
BR8805492A (en) 1989-07-04
DE3736501C1 (en) 1988-06-09
ES2023993T5 (en) 1998-08-01
YU46574B (en) 1993-11-16
CN1033841A (en) 1989-07-12
CA1308631C (en) 1992-10-13
NO884389D0 (en) 1988-10-04
YU193788A (en) 1990-04-30
NO169244C (en) 1992-05-27
RO110067B1 (en) 1995-09-29
NO169244B (en) 1992-02-17
PL159767B1 (en) 1993-01-29
AU606473B2 (en) 1991-02-07
US4867808A (en) 1989-09-19
ES2023993B3 (en) 1992-02-16
US4867808B1 (en) 1994-02-22
DK167497B1 (en) 1993-11-08
CN1015066B (en) 1991-12-11
CS711188A2 (en) 1990-10-12
HU204102B (en) 1991-11-28
RU1813104C (en) 1993-04-30
DK596588A (en) 1989-04-29
PT88896A (en) 1989-09-14
JPH01149920A (en) 1989-06-13
BG49828A3 (en) 1992-02-14
FI86560B (en) 1992-05-29
JP3068135B2 (en) 2000-07-24
DD283421A5 (en) 1990-10-10
ZA886853B (en) 1989-05-30
FI86560C (en) 1992-09-10
FI884513A (en) 1989-04-29
CS274632B2 (en) 1991-09-15
HRP920581A2 (en) 1995-02-28
EP0313888B2 (en) 1998-06-17
AU2440488A (en) 1989-05-04
DE3864007D1 (en) 1991-09-05
IL87762A0 (en) 1989-02-28
UA13002A (en) 1997-02-28
DK596588D0 (en) 1988-10-27
HUT49651A (en) 1989-10-30
ATE65801T1 (en) 1991-08-15
SI8811937A8 (en) 1997-06-30

Similar Documents

Publication Publication Date Title
EP0313888B1 (en) Method for the heat treatment of metallic work pieces
EP0313889B1 (en) Vacuum furnace for the heat treatment of metallic work-pieces
DE4422588C2 (en) Process for quenching workpieces with gases and heat treatment system to carry out the process
DE60128615T2 (en) Device for quenching metallic materials
DE880311C (en) Process for surface hardening of hardenable metallic materials
EP0103705A1 (en) Method of heat treating work pieces
DE10035420A1 (en) Method and device for cooling annealed coils in a bell-type furnace
DE102008036490B4 (en) High pressure gas quenching process and apparatus therefor
DE886002C (en) Process for hardening sheet metal
DE102019208807A1 (en) Process and system for batch heat treatment of light metal castings
DE3120509C2 (en) Process for gas nitriding of workpieces made of steel
DE60208405T2 (en) HEAT TREATMENT PROCESS
AT315978B (en) Vacuum electric furnace with low thermal inertia
US3723198A (en) Method of straightening elongate inductively heated workpieces
DE879554C (en) Process to improve the strength properties of nitrided workpieces
DE2636276A1 (en) Bright annealing steel in vacuo or inert gas - using long preheating cycle to remove organic matter from surface of steel
DD154726A1 (en) PROCESS FOR PARTIAL TRANSPORTATION ON PISTONS
DE1198569B (en) Use of the fluidized bed bath for quenching metallic workpieces
DE1103366B (en) Process for cooling highly stressed parts in metallurgical or chemical furnaces
DE1154928B (en) Process for the heat treatment of panels made of chips or wood fiber material
DD290665A5 (en) DEVICE FOR AUTOMATIC HEAT TREATMENT OF WORKPIECES
Sobue et al. Optimum Induction Hardening Conditions of Ductile Iron
DE2238828B1 (en) Air cooling system - for cooling material directly heated in a vacuum elec-tric furnace
DE1176377B (en) Process to increase the stress-corrosion resistance of pipes and other hollow bodies
DE2500408A1 (en) Heat treatment plant for mfg. malleable cast iron - using row of fluidised beds with optimum flow of gases and air

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 19881005

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE CH DE ES FR GB IT LI LU NL SE

17Q First examination report despatched

Effective date: 19900928

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AT BE CH DE ES FR GB IT LI LU NL SE

REF Corresponds to:

Ref document number: 65801

Country of ref document: AT

Date of ref document: 19910815

Kind code of ref document: T

ITF It: translation for a ep patent filed

Owner name: JACOBACCI & PERANI S.P.A.

ET Fr: translation filed
REF Corresponds to:

Ref document number: 3864007

Country of ref document: DE

Date of ref document: 19910905

GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)
REG Reference to a national code

Ref country code: ES

Ref legal event code: FG2A

Ref document number: 2023993

Country of ref document: ES

Kind code of ref document: B3

PLBI Opposition filed

Free format text: ORIGINAL CODE: 0009260

PLBI Opposition filed

Free format text: ORIGINAL CODE: 0009260

26 Opposition filed

Opponent name: IPSEN INDUSTRIES INTERNATIONAL GESELLSCHAFT MIT BE

Effective date: 19920213

PLBI Opposition filed

Free format text: ORIGINAL CODE: 0009260

26 Opposition filed

Opponent name: IPSEN INDUSTRIES INTERNATIONAL GESELLSCHAFT MIT BE

Effective date: 19920213

Opponent name: THYSSEN EDELSTAHLWERKE AG

Effective date: 19920325

PLAB Opposition data, opponent's data or that of the opponent's representative modified

Free format text: ORIGINAL CODE: 0009299OPPO

NLR1 Nl: opposition has been filed with the epo

Opponent name: IPSEN INDUSTRIES INTERNATIONAL GMBH

26 Opposition filed

Opponent name: IPSEN INDUSTRIES INTERNATIONAL GESELLSCHAFT MIT BE

Effective date: 19920213

Opponent name: LINDE AKTIENGESELLSCHAFT, WIESBADEN

Effective date: 19920429

Opponent name: THYSSEN EDELSTAHLWERKE AG

Effective date: 19920325

R26 Opposition filed (corrected)

Opponent name: IPSEN INDUSTRIES INTERNATIONAL GESELLSCHAFT MIT BE

Effective date: 19920213

NLR1 Nl: opposition has been filed with the epo

Opponent name: THYSSEN EDELSTAHLWERKE AG

NLR1 Nl: opposition has been filed with the epo

Opponent name: LINDE AG

RAP2 Party data changed (patent owner data changed or rights of a patent transferred)

Owner name: LEYBOLD DURFERRIT GMBH

NLT2 Nl: modifications (of names), taken from the european patent patent bulletin

Owner name: LEYBOLD DURFERRIT GMBH TE KEULEN, BONDSREPUBLIEK D

RAP4 Party data changed (patent owner data changed or rights of a patent transferred)

Owner name: LEYBOLD DURFERRIT GMBH

EPTA Lu: last paid annual fee
REG Reference to a national code

Ref country code: FR

Ref legal event code: TP

EAL Se: european patent in force in sweden

Ref document number: 88116477.6

REG Reference to a national code

Ref country code: CH

Ref legal event code: PUE

Owner name: DEGUSSA AKTIENGESELLSCHAFT TRANSFER- ALD VACUUM TE

RAP2 Party data changed (patent owner data changed or rights of a patent transferred)

Owner name: ALD VACUUM TECHNOLOGIES GMBH

NLS Nl: assignments of ep-patents

Owner name: ALD VACUUM TECHNOLOGIES GMBH

NLT2 Nl: modifications (of names), taken from the european patent patent bulletin

Owner name: ALD VACUUM TECHNOLOGIES GMBH

REG Reference to a national code

Ref country code: FR

Ref legal event code: TP

APAC Appeal dossier modified

Free format text: ORIGINAL CODE: EPIDOS NOAPO

PLAW Interlocutory decision in opposition

Free format text: ORIGINAL CODE: EPIDOS IDOP

PUAH Patent maintained in amended form

Free format text: ORIGINAL CODE: 0009272

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: PATENT MAINTAINED AS AMENDED

27A Patent maintained in amended form

Effective date: 19980617

AK Designated contracting states

Kind code of ref document: B2

Designated state(s): AT BE CH DE ES FR GB IT LI LU NL SE

REG Reference to a national code

Ref country code: GB

Ref legal event code: 732E

GBTA Gb: translation of amended ep patent filed (gb section 77(6)(b)/1977)
REG Reference to a national code

Ref country code: CH

Ref legal event code: AEN

Free format text: AUFRECHTERHALTUNG DES PATENTES IN GEAENDERTER FORM

REG Reference to a national code

Ref country code: ES

Ref legal event code: DC2A

Kind code of ref document: T5

Effective date: 19980701

NLR2 Nl: decision of opposition
ET3 Fr: translation filed ** decision concerning opposition
ITF It: translation for a ep patent filed

Owner name: JACOBACCI & PERANI S.P.A.

NLR3 Nl: receipt of modified translations in the netherlands language after an opposition procedure
REG Reference to a national code

Ref country code: CH

Ref legal event code: PFA

Free format text: ALD VACUUM TECHNOLOGIES GMBH TRANSFER- ALD VACUUM TECHNOLOGIES AG

NLS Nl: assignments of ep-patents

Owner name: ALD VACUUM TECHNOLOGIES AG

REG Reference to a national code

Ref country code: ES

Ref legal event code: PC2A

REG Reference to a national code

Ref country code: FR

Ref legal event code: CJ

Ref country code: FR

Ref legal event code: CA

REG Reference to a national code

Ref country code: GB

Ref legal event code: IF02

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: CH

Payment date: 20040917

Year of fee payment: 17

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: NL

Payment date: 20040921

Year of fee payment: 17

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: BE

Payment date: 20041015

Year of fee payment: 17

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: LU

Payment date: 20041129

Year of fee payment: 17

APAH Appeal reference modified

Free format text: ORIGINAL CODE: EPIDOSCREFNO

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: LU

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20051005

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: CH

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20051031

Ref country code: LI

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20051031

Ref country code: BE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20051031

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: NL

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20060501

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

NLV4 Nl: lapsed or anulled due to non-payment of the annual fee

Effective date: 20060501

BERE Be: lapsed

Owner name: *ALD VACUUM TECHNOLOGIES G.M.B.H.

Effective date: 20051031

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20070921

Year of fee payment: 20

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: ES

Payment date: 20071015

Year of fee payment: 20

Ref country code: DE

Payment date: 20070921

Year of fee payment: 20

Ref country code: IT

Payment date: 20070915

Year of fee payment: 20

Ref country code: SE

Payment date: 20070917

Year of fee payment: 20

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: AT

Payment date: 20070911

Year of fee payment: 20

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20070912

Year of fee payment: 20

REG Reference to a national code

Ref country code: GB

Ref legal event code: PE20

Expiry date: 20081004

EUG Se: european patent has lapsed
REG Reference to a national code

Ref country code: ES

Ref legal event code: FD2A

Effective date: 20081006

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: ES

Free format text: LAPSE BECAUSE OF EXPIRATION OF PROTECTION

Effective date: 20081006

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF EXPIRATION OF PROTECTION

Effective date: 20081004