EP 0375491 A1 19900627 - Method and installation for heat treatment for case-hardening, carbonitriding or heating before the quenching of metallic work pieces.
Title (en)
Method and installation for heat treatment for case-hardening, carbonitriding or heating before the quenching of metallic work pieces.
Title (de)
Verfahren und Anlage für Wärmebehandlungen wie Einsatzhärten, Karbonitrieren oder Erwärmung vor dem Härten von metallischen Werkstoffen.
Title (fr)
Procédé et installation de traitement thermique de cémentation, carbonitruration ou chauffage avant trempe de pièces métalliques.
Publication
Application
Priority
FR 8816792 A 19881220
Abstract (en)
[origin: US5045126A] The invention is exclusively concerned with heat treatments before hardening, of metallic pieces, by cementation, carbonitridation and heating. The process concerns the feeding of a non muffle heat treatment furnace with various components including nitrogen which is produced by an adsorption or selective permeation generator and which has a residual oxygen content of the order of 2%. According to the invention, after the furnace has ceased to be in operation for a substantial period of time, it is reconditioned by injecting purer nitrogen which has a residual oxygen content lower than 0.3% and which is produced by said generator, adjusted at a lower extraction rate.
Abstract (fr)
L'invention concerne exclusivement les traitements thermiques de cémentation, carbonitruration, et chauffage avant trempe de pièces métalliques. Le procédé concerne l'alimentation d'un four non moufflé de traitement thermique à partir de différents constituants, dont de l'azote qui est fourni par un générateur (1) à adsorption ou à perméation sélective et qui présente une teneur résiduelle en oxygène de l'ordre de 2 % (via 2, 3, 4, 5, 6, 7). Selon l'invention, on assure, après un arrêt de fonctionnement de durée significative, un reconditionnement du four par l'injection d'azote plus pur, à teneur résiduelle en oxygène inférieure à 0,3 %, fourni par ledit générateur réglé sur un taux d'extraction plus faible, (via 2, 3, 8, 4, 5, 9, 7).
IPC 1-7
IPC 8 full level
C23C 8/32 (2006.01); C21D 1/74 (2006.01); C21D 1/76 (2006.01); C23C 8/30 (2006.01)
CPC (source: EP US)
C21D 1/74 (2013.01 - EP US); C21D 1/76 (2013.01 - EP US); C23C 8/30 (2013.01 - EP US)
Citation (search report)
- [Y] IRON AND STEEL ENGINEER, vol. 39, no. 8, août 1962, pages 124-134; R. HERBERT et al.: "Nitrogen from an air-separation plant as a heat-treating atmosphere"
- [Y] METAL PROGRESS, vol. 127, no. 6, mai 1985, page 67, Metals Park, Ohio, US; "New products: New air separation technology makes nitrogen for heat treating"
- [A] STEEL IN THE U.S.S.R., vol. 15, no. 12, décembre 1985, pages 610-611, Londres, GB; V.M. REBIKOV: "Single-component controlled atmosphere in muffle-less shaft type electric furnaces"
- [A] JOURNAL OF HEAT TREATING, vol. 5, no. 2, 1988, pages 97-114, Springer-Verlag, New York Inc., New York, US; J. SLYCKE et al.: "Assessment of nitrogen based atmospheres for industrial heat treating"
Designated contracting state (EPC)
AT BE CH DE ES FR GB GR IT LI LU NL SE
DOCDB simple family (publication)
EP 0375491 A1 19900627; EP 0375491 B1 19940413; AT E104361 T1 19940415; AU 4713389 A 19900628; AU 625618 B2 19920716; CA 2005823 A1 19900620; CA 2005823 C 19941213; DE 68914624 D1 19940519; DE 68914624 T2 19940721; ES 2050834 T3 19940601; FR 2640646 A1 19900622; FR 2640646 B1 19930205; JP H02217459 A 19900830; PT 92615 A 19900629; PT 92615 B 19950912; US 5045126 A 19910903; ZA 899627 B 19900926
DOCDB simple family (application)
EP 89403347 A 19891204; AT 89403347 T 19891204; AU 4713389 A 19891220; CA 2005823 A 19891218; DE 68914624 T 19891204; ES 89403347 T 19891204; FR 8816792 A 19881220; JP 32620289 A 19891218; PT 9261589 A 19891219; US 45243289 A 19891219; ZA 899627 A 19891215