EP0647726A1 - Method for treatment of pieces - Google Patents

Method for treatment of pieces Download PDF

Info

Publication number
EP0647726A1
EP0647726A1 EP94202679A EP94202679A EP0647726A1 EP 0647726 A1 EP0647726 A1 EP 0647726A1 EP 94202679 A EP94202679 A EP 94202679A EP 94202679 A EP94202679 A EP 94202679A EP 0647726 A1 EP0647726 A1 EP 0647726A1
Authority
EP
European Patent Office
Prior art keywords
parts
reaction gas
hardening
furnace
reducing
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP94202679A
Other languages
German (de)
French (fr)
Other versions
EP0647726B1 (en
Inventor
Hans-Peter Schmidt
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.)
Messer Griesheim GmbH
Original Assignee
Messer Griesheim 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 Messer Griesheim GmbH filed Critical Messer Griesheim GmbH
Publication of EP0647726A1 publication Critical patent/EP0647726A1/en
Application granted granted Critical
Publication of EP0647726B1 publication Critical patent/EP0647726B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
    • C23C8/06—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases
    • C23C8/08—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases only one element being applied
    • C23C8/10—Oxidising
    • C23C8/16—Oxidising using oxygen-containing compounds, e.g. water, carbon dioxide
    • C23C8/18—Oxidising of ferrous surfaces
    • 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
    • C21D1/76—Adjusting the composition of the atmosphere

Definitions

  • the invention relates to a method for treating parts, in particular steel and / or cast parts.
  • Steel parts are heated to the respective austenitizing temperature in a furnace using protective gases such as nitrogen, nitrogen / propane mixture, endogas, exogas and the like and hardened by quenching agents at any quenching rate.
  • protective gases such as nitrogen, nitrogen / propane mixture, endogas, exogas and the like and hardened by quenching agents at any quenching rate.
  • the invention has for its object to provide a method for bluing parts during curing.
  • a subsequent oxidation treatment can be dispensed with by the invention, since the steel and / or castings receive a uniform, thin oxide layer (iron oxide) by introducing or atomizing a reducing and at the same time oxidizing reaction gas in the furnace chamber during the hardening process at the respective hardening temperature.
  • the simultaneous blueing and hardening of the parts increases the efficiency of the process.
  • the amounts of hydrocarbons used to generate the flame curtain could be almost halved by feeding in the reaction gas.
  • the soot formation is greatly reduced by incomplete combustion of the flame gases, for example the propane, so that the cleaning intervals of the furnace space are also increased.
  • a reducing and at the same time oxidizing reaction gas is fed into a hardening furnace via a known injector spray lance, thereby creating a gas atmosphere which has a slightly oxidizing effect.
  • the pure, liquid substances methanol and water as well as gaseous nitrogen are preferably mixed with the help of the injector spray lance and reach the hot part of the furnace, finely atomized, through the outlet holes. Due to the high furnace temperature, the liquid substances evaporate, whereby gaseous methanol splits into two parts hydrogen and one part carbon monoxide. Methanol fission gas is the reducing component, while water vapor is the oxidizing component.
  • Nitrogen is used to atomize the liquid substances and to dilute the oxidizing and reducing components of the gas atmosphere.
  • the hardened material is placed outside the furnace on a transport system and transported to the furnace chamber.
  • the parts are heated to the respective austenitizing temperature (860 - 940 ° C) and then suddenly fall into a quenching bath, especially an oil or salt bath.
  • a quenching bath especially an oil or salt bath.
  • the surface of the parts is easily oxidized by the water vapor in the gas atmosphere of the furnace. So that the oxidation of the parts does not already take place at low temperatures, the flame curtain, which is located in the lower part of the furnace inlet, is optimally adjusted, i.e.
  • the amount of propane or natural gas (hydrocarbons) is matched to the amount of reaction gas fed in so that the flame curtain binds oxygen, thus preventing early oxidation of the parts to be hardened.
  • the flame curtain is installed across the conveying direction.
  • the amounts of propane are 100 - 2000 l / h and the reaction gas amounts are 2 - 20 m3 / h.
  • the new process made it possible to achieve uniform and well-adhering layers (blue color) when hardening steel parts. No blistering was found.

Abstract

In a process for treating parts, esp. steel and/or cast iron parts, the parts are subjected to combined oxidn. (blueing) and hardening by introduction or injection of a reducing and oxidising reaction gas at the hardening temp. into the treatment furnace. Pref. the reaction gas is produced using a methanol-water mixt.

Description

Die Erfindung betrifft ein Verfahren zum Behandeln von Teilen, insbesondere Stahl- und/oder Gußteilen.The invention relates to a method for treating parts, in particular steel and / or cast parts.

Stahlteile werden unter Einsatz von Schutzgasen, wie Stickstoff, Stickstoff/Propan-Gemisch, Endogas, Exogas und dergleichen in einem Ofen auf die jeweilige Austenitisierungstemperatur erwärmt und durch Abschreckmittel mit beliebigen Abschreckgeschwindigkeiten gehärtet.Steel parts are heated to the respective austenitizing temperature in a furnace using protective gases such as nitrogen, nitrogen / propane mixture, endogas, exogas and the like and hardened by quenching agents at any quenching rate.

Viele der gehärteten Stahlteile werden anschließend in einer zweiten Wärmebehandlung bei Temperaturen zwischen 300 und 570°C oxidiert, um eine visuell ansprechendere Oberfläche zu bekommen und das Werkstück gegen Flugrost korrosionsbeständiger und gegen Abrieb widerstandsfähiger zu machen. Es bildet sich ein blaues Eisenoxid Fe₃ O₄, das zu dem Begriff "Bläuen" geführt hat.Many of the hardened steel parts are then oxidized in a second heat treatment at temperatures between 300 and 570 ° C in order to obtain a more visually appealing surface and to make the workpiece more corrosion-resistant and more resistant to abrasion. A blue iron oxide forms Fe₃ O₄, which has led to the term "blueness".

Mit den herkömmlichen Schutzgasen, die beim Härteprozeß zum Einsatz kommen, ist ein Oxidieren (Bläuen) der Oberfläche der Stahlteile nicht möglich.With the conventional protective gases used in the hardening process, it is not possible to oxidize (blue) the surface of the steel parts.

Der Erfindung liegt die Aufgabe zugrunde, ein Verfahren zum Bläuen von Teilen während des Härtens zu schaffen.The invention has for its object to provide a method for bluing parts during curing.

Ausgehend von dem im Oberbegriff des Anspruches 1 berücksichtigten Stand der Technik ist diese Aufgabe erfindungsgemäß gelöst mit den im kennzeichnenden Teil des Anspruches 1 angegebenen Merkmalen.Starting from the prior art taken into account in the preamble of claim 1, this object is achieved according to the invention with the features specified in the characterizing part of claim 1.

Vorteilhafte Weiterbildungen der Erfindung sind in den Unteransprüchen angegeben.Advantageous developments of the invention are specified in the subclaims.

Durch die Erfindung kann auf eine nachgeschaltete Oxidationsbehandlung verzichtet werden, da die Stahl- und/oder Gußteile eine gleichmäßig, dünne Oxidschicht (Eisenoxid) durch Einleiten oder Verdüsen eines reduzierenden und gleichzeitig oxidierenden Reaktionsgases im Ofenraum während dem Härteprozeß bei der jeweiligen Härtetemperatur erhalten. Das gleichzeitige Bläuen und Härten der Teile erhöht die Wirtschaftlichkeit des Verfahrens. Überraschenderweise konnten die zum Erzeugen des Flammenschleiers verwendeten Mengen an Kohlenwasserstoffen durch Einspeisen des Reaktionsgases fast halbiert werden. Durch die Einspeisung der oxidierenden Komponenten wie Wasser, Kohlendioxid oder Luft wird die Rußbildung durch unvollständige Verbrennung der Flammengase, beispielsweise des Propans, stark gemindert, so daß die Reinigungsintervalle des Ofenraumes ebenfalls größer werden.A subsequent oxidation treatment can be dispensed with by the invention, since the steel and / or castings receive a uniform, thin oxide layer (iron oxide) by introducing or atomizing a reducing and at the same time oxidizing reaction gas in the furnace chamber during the hardening process at the respective hardening temperature. The simultaneous blueing and hardening of the parts increases the efficiency of the process. Surprisingly, the amounts of hydrocarbons used to generate the flame curtain could be almost halved by feeding in the reaction gas. By feeding in the oxidizing components such as water, carbon dioxide or air, the soot formation is greatly reduced by incomplete combustion of the flame gases, for example the propane, so that the cleaning intervals of the furnace space are also increased.

Durch die Erfindung wird ein reduzierendes und gleichzeitig oxidierendes Reaktionsgas über eine an sich bekannte Injektor-Sprühlanze in einen Härteofen eingespeist und dadurch eine Gasatmosphäre geschaffen, die leicht oxidierend wirkt. Als Reaktionsgas werden bevorzugt die reinen, flüssigen Stoffe Methanol und Wasser sowie gasförmiger Stickstoff mit Hilfe der Injektor-Sprühlanze gemischt und gelangen über die Austrittsbohrungen fein verdüst in den heißen Teil des Ofenraumes. Durch die hohe Ofentemperatur verdampfen die flüssigen Stoffe, wobei sich gasförmiges Methanol in zwei Teile Wasserstoff und einen Teil Kohlenmonoxid aufspaltet. Methanol-Spaltgas bildet die reduzierende Komponente, während Wasserdampf die oxidierende darstellt. Stickstoff dient zur Verdüsung der flüssigen Stoffe und zur Verdünnung der oxidierenden und reduzierenden Bestandteile der Gasatmosphären. Das Härtegut wird außerhalb des Ofens auf ein Transportsystem gelegt und über dieses in den Ofenraum befördert. Im Ofenraum werden die Teile auf die jeweilige Austenitisierungstemperatur (860 - 940°C) erwärmt und fallen dann schlagartig in ein Abschreckbad, insbesondere ein Öl- bzw. Salzbad. Während der Aufheiz- und/oder Haltephase wird die Oberfläche der Teile durch den Wasserdampf in der Gasatmosphäre des Ofens leicht oxidiert. Damit die Oxidation der Teile nicht schon bei niedrigen Temperaturen erfolgt, wird der Flammenschleier, der sich im unteren Teil des Ofeneinlaufes befindet, optimal eingestellt, d.h., die Menge an Propan oder Erdgas (Kohlenwasserstoffe) wird so auf die eingespeiste Menge des Reaktionsgases abgestimmt, daß der Flammenschleier Sauerstoff abbindet und somit eine frühzeitige Oxidation der zu härtenden Teile verhindert wird. Der Flammenschleier ist quer zur Förderrichtung installiert. Die Mengen an Propan liegen bei 100 - 2000 l/h und die Reaktionsgasmengen bei 2 - 20 m³/h.By means of the invention, a reducing and at the same time oxidizing reaction gas is fed into a hardening furnace via a known injector spray lance, thereby creating a gas atmosphere which has a slightly oxidizing effect. As the reaction gas, the pure, liquid substances methanol and water as well as gaseous nitrogen are preferably mixed with the help of the injector spray lance and reach the hot part of the furnace, finely atomized, through the outlet holes. Due to the high furnace temperature, the liquid substances evaporate, whereby gaseous methanol splits into two parts hydrogen and one part carbon monoxide. Methanol fission gas is the reducing component, while water vapor is the oxidizing component. Nitrogen is used to atomize the liquid substances and to dilute the oxidizing and reducing components of the gas atmosphere. The hardened material is placed outside the furnace on a transport system and transported to the furnace chamber. In the furnace chamber, the parts are heated to the respective austenitizing temperature (860 - 940 ° C) and then suddenly fall into a quenching bath, especially an oil or salt bath. During the heating and / or holding phase, the surface of the parts is easily oxidized by the water vapor in the gas atmosphere of the furnace. So that the oxidation of the parts does not already take place at low temperatures, the flame curtain, which is located in the lower part of the furnace inlet, is optimally adjusted, i.e. the amount of propane or natural gas (hydrocarbons) is matched to the amount of reaction gas fed in so that the flame curtain binds oxygen, thus preventing early oxidation of the parts to be hardened. The flame curtain is installed across the conveying direction. The amounts of propane are 100 - 2000 l / h and the reaction gas amounts are 2 - 20 m³ / h.

Durch das neue Verfahren konnten gleichmäßige und gut haftende Schichten (blaue Farbe) beim Härten von Stahlteilen eingestellt werden. Eine Blasenbildung wurde nicht festgestellt.The new process made it possible to achieve uniform and well-adhering layers (blue color) when hardening steel parts. No blistering was found.

Das Verfahren nach der Erfindung wurde vorstehend mit dem Reaktionsgas Stickstoff-Methanol-Wasser beschrieben. Es ist selbstverständlich auch mit anderen Reaktionsgasen durchführbar, die eine reduzierende und oxidierende Komponente aufweisen.The process according to the invention has been described above with the reaction gas nitrogen-methanol-water. Of course, it can also be carried out with other reaction gases which have a reducing and oxidizing component.

Claims (4)

Verfahren zum Behandeln von Teilen, insbesondere Stahl- und/oder Gußteilen,
gekennzeichnet durch ein gemeinsames Oxidieren (Bläuen) und Härten der Teile in einem Ofen mittels Einleiten oder Verdüsen eines reduzierenden und oxidierenden Reaktionsgases bei Härtetemperaturen in den Ofenraum.Process for treating parts, especially steel and / or cast parts,
characterized by a joint oxidation (blueing) and hardening of the parts in an oven by introducing or atomizing a reducing and oxidizing reaction gas at curing temperatures into the oven chamber. Verfahren nach Anspruch 1,
dadurch gekennzeichnet,
daß das Reaktionsgas ein Methanol-Wasser-Gemisch ist.Method according to claim 1,
characterized,
that the reaction gas is a methanol-water mixture. Verfahren nach Anspruch 1 oder 2,
dadurch gekennzeichnet,
daß das Reaktionsgas als Flüssigkeit vorliegt, die mit gasförmigem Stickstoff in dem Ofen verdüst und verdünnt wird.The method of claim 1 or 2,
characterized,
that the reaction gas is in the form of a liquid which is atomized and diluted with gaseous nitrogen in the furnace. Verfahren nach einem der Ansprüche 1 bis 3,
dadurch gekennzeichnet,
daß das Reaktionsgas im dem Teil des Ofenraumes verdüst wird, in welchem die Teile auf die Endtemperatur beim Härten erwärmt werden.Method according to one of claims 1 to 3,
characterized,
that the reaction gas is atomized in the part of the furnace chamber in which the parts are heated to the final temperature during hardening.
EP94202679A 1993-10-06 1994-09-16 Method for treatment of pieces Expired - Lifetime EP0647726B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE4333940 1993-10-06
DE4333940A DE4333940C1 (en) 1993-10-06 1993-10-06 Process for treating parts

Publications (2)

Publication Number Publication Date
EP0647726A1 true EP0647726A1 (en) 1995-04-12
EP0647726B1 EP0647726B1 (en) 1999-12-08

Family

ID=6499463

Family Applications (1)

Application Number Title Priority Date Filing Date
EP94202679A Expired - Lifetime EP0647726B1 (en) 1993-10-06 1994-09-16 Method for treatment of pieces

Country Status (3)

Country Link
EP (1) EP0647726B1 (en)
AT (1) ATE187504T1 (en)
DE (2) DE4333940C1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10156326A1 (en) * 2001-11-19 2003-06-26 Joerg Schilling Surface decoration and surface hardening of ferrometallic parts includes encasing the parts with lattice-like shell elements made from an inert material, and embedding the encased parts in a carbon mixed granulate
EP2497839A1 (en) 2011-03-10 2012-09-12 SOL S.p.A. Method for the treatment of steels

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19736514C5 (en) * 1997-08-22 2004-11-25 Messer Griesheim Gmbh Process for jointly oxidizing and heat treating parts
DE19937186C1 (en) * 1999-08-06 2000-09-07 Mannesmann Sachs Ag Ferrous metal part is surface oxidized, e.g. for corrosion protection of steel clutch, torsion vibration damper and/or flywheel components, by exposing the heated part to an oxygen-rich atmosphere and gas cooling
DE10235131A1 (en) 2002-08-01 2004-02-19 Ipsen International Gmbh Method and device for blackening components
DE102010032919B4 (en) * 2010-07-30 2023-10-05 Air Liquide Deutschland Gmbh Method and device for humidifying a combustible gas

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0284233A1 (en) * 1987-03-07 1988-09-28 Kabushiki Kaisha Toshiba Furnace for formation of black oxide film on the surface of thin metal sheet and method for formation of black oxide film on the surface of shadow mask material by use of said furnace
GB2233672A (en) * 1989-06-30 1991-01-16 Shell Int Research High temperature treatment of stainless steals used in high temperature reactors
GB2234530A (en) * 1989-06-30 1991-02-06 Shell Int Research Heat treatment of high temperature steels

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE918933C (en) * 1950-07-27 1954-10-07 Robert Von Linde Dipl Ing Process for the production of a flammable bright glow gas
US2673821A (en) * 1950-11-18 1954-03-30 Midwest Research Inst Heat treatment of steel in a protective atmosphere

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0284233A1 (en) * 1987-03-07 1988-09-28 Kabushiki Kaisha Toshiba Furnace for formation of black oxide film on the surface of thin metal sheet and method for formation of black oxide film on the surface of shadow mask material by use of said furnace
GB2233672A (en) * 1989-06-30 1991-01-16 Shell Int Research High temperature treatment of stainless steals used in high temperature reactors
GB2234530A (en) * 1989-06-30 1991-02-06 Shell Int Research Heat treatment of high temperature steels

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10156326A1 (en) * 2001-11-19 2003-06-26 Joerg Schilling Surface decoration and surface hardening of ferrometallic parts includes encasing the parts with lattice-like shell elements made from an inert material, and embedding the encased parts in a carbon mixed granulate
DE10156326B4 (en) * 2001-11-19 2004-02-12 Schilling, Jörg, Dipl.-Ing. Process for surface decoration and surface hardening of ferrometallic parts
EP2497839A1 (en) 2011-03-10 2012-09-12 SOL S.p.A. Method for the treatment of steels

Also Published As

Publication number Publication date
DE4333940C1 (en) 1994-12-08
ATE187504T1 (en) 1999-12-15
DE59408983D1 (en) 2000-01-13
EP0647726B1 (en) 1999-12-08

Similar Documents

Publication Publication Date Title
EP0647726B1 (en) Method for treatment of pieces
DE19736514C5 (en) Process for jointly oxidizing and heat treating parts
US4317687A (en) Carburizing process utilizing atmospheres generated from nitrogen-ethanol based mixtures
DE3630833A1 (en) METHOD AND DEVICE FOR HEAT TREATING METAL WORKPIECES
EP1673483B1 (en) Method for heat-treating iron-containing materials
EP0430313B1 (en) Method and device for producing a protective atmosphere
EP0703994B1 (en) Method and device for the heat treatment of workpieces
DE19523956A1 (en) Carburisation or carbonitriding with min. carbon di:oxide and no cyanide emissions
WO1999011829A1 (en) Method and device for thermal treatment of parts
DE954607C (en) Process for decarburizing the surface layers of workpieces made of iron or steel
US5194096A (en) Carburizing treatment of a steel with reduction of the hydrogen content in the carburized layer
DE3500935A1 (en) COMPONENT WITH CORROSION-RESISTANT OXIDIC COATING APPLIED ON OPPOSITE SIDES OF A METAL CONSTRUCTION
DE2419997C2 (en) Method and device for producing hardenable or wear-resistant surface layers of steel parts in an annealing furnace
DE4034235C2 (en) Sooting workpieces for carbon-neutral heat treatment
DE10118029C1 (en) Process for the thermo-chemical pre-treatment of metallic workpieces, especially case hardening steel is carried out in an atmosphere containing hydrogen and hydrogen-containing gases to which oxygen and air are added
DE3120509C2 (en) Process for gas nitriding of workpieces made of steel
DE2822048A1 (en) Gas mfg. plant for use in heat treatment of metals - using catalytic combustion of hydrocarbon, esp. to obtain gas for carburising or bright annealing treatments
DE3808146A1 (en) METHOD FOR PRODUCING A PROTECTIVE GAS FOR THE HEAT TREATMENT OF IRON AND NON-FERROUS METALS
DE3037643A1 (en) METHOD AND DEVICE FOR THE DECOLARIZING OR COAL-NEUTRAL GLOWING OF METAL PARTS
DE10162339A1 (en) Process for producing an oxide layer on metal parts
EP0364709A1 (en) Method of producing a gas-annealing atmosphere in a heat-treating device
DE14196C (en) Innovations in the creation of a rust-proof cover on objects made of iron and steel together with the ovens used for them
DE3422608A1 (en) Process and apparatus for producing a gas atmosphere containing carbon monoxide and hydrogen
WO2002044617A1 (en) Method of combustion and impulse current controlled fuel/oxygen lance
DE3222322A1 (en) METHOD FOR PRODUCING A NITROGEN AND HYDROGEN CONTAINING GAS ATMOSPHERES

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

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE DE FR GB IT

17P Request for examination filed

Effective date: 19951012

17Q First examination report despatched

Effective date: 19970515

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AT BE DE FR GB IT

REF Corresponds to:

Ref document number: 187504

Country of ref document: AT

Date of ref document: 19991215

Kind code of ref document: T

REF Corresponds to:

Ref document number: 59408983

Country of ref document: DE

Date of ref document: 20000113

GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)

Effective date: 20000110

ITF It: translation for a ep patent filed

Owner name: DE DOMINICIS & MAYER S.R.L.

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

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

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
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: FR

Payment date: 20050823

Year of fee payment: 12

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

Ref country code: AT

Payment date: 20050913

Year of fee payment: 12

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

Ref country code: BE

Payment date: 20051201

Year of fee payment: 12

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

Ref country code: AT

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

Effective date: 20060916

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

Ref country code: BE

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

Effective date: 20060930

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

Ref country code: IT

Payment date: 20060930

Year of fee payment: 13

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

Effective date: 20070531

BERE Be: lapsed

Owner name: *MESSER GRIESHEIM G.M.B.H.

Effective date: 20060930

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

Ref country code: FR

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

Effective date: 20061002

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

Ref country code: IT

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

Effective date: 20070916

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

Ref country code: DE

Payment date: 20130919

Year of fee payment: 20

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

Ref country code: GB

Payment date: 20130919

Year of fee payment: 20

REG Reference to a national code

Ref country code: DE

Ref legal event code: R071

Ref document number: 59408983

Country of ref document: DE

REG Reference to a national code

Ref country code: GB

Ref legal event code: PE20

Expiry date: 20140915

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

Ref country code: DE

Free format text: LAPSE BECAUSE OF EXPIRATION OF PROTECTION

Effective date: 20140917

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: 20140915