EP0093060A1 - Drehherdofen zur thermischen, thermochemischen oder elektrothermischen Behandlung von Metallen in verdünnter Atmosphäre - Google Patents

Drehherdofen zur thermischen, thermochemischen oder elektrothermischen Behandlung von Metallen in verdünnter Atmosphäre Download PDF

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Publication number
EP0093060A1
EP0093060A1 EP83400814A EP83400814A EP0093060A1 EP 0093060 A1 EP0093060 A1 EP 0093060A1 EP 83400814 A EP83400814 A EP 83400814A EP 83400814 A EP83400814 A EP 83400814A EP 0093060 A1 EP0093060 A1 EP 0093060A1
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EP
European Patent Office
Prior art keywords
tunnel
enclosure
treatment
parts
door
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
EP83400814A
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English (en)
French (fr)
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EP0093060B1 (de
Inventor
Jean Bares
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.)
Le Traitement Sous Vide SA
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Le Traitement Sous Vide SA
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Publication date
Application filed by Le Traitement Sous Vide SA filed Critical Le Traitement Sous Vide SA
Priority to AT83400814T priority Critical patent/ATE21967T1/de
Publication of EP0093060A1 publication Critical patent/EP0093060A1/de
Application granted granted Critical
Publication of EP0093060B1 publication Critical patent/EP0093060B1/de
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Classifications

    • 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
    • F27B9/00—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity
    • F27B9/14—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity characterised by the path of the charge during treatment; characterised by the means by which the charge is moved during treatment
    • F27B9/16—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity characterised by the path of the charge during treatment; characterised by the means by which the charge is moved during treatment the charge moving in a circular or arcuate path
    • 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
    • F27B9/00—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity
    • F27B9/04—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity adapted for treating the charge in vacuum or special atmosphere
    • F27B9/042—Vacuum furnaces

Definitions

  • the present invention relates to a rotary hearth furnace for the thermal, thermochemical or electrothermal treatment of metals in a rarefied atmosphere.
  • thermochemical treatment of metals optionally by ion bombardment, comprising, at the end of the treatment cycle, a final treatment, of limited duration, such as quenching.
  • thermochemical vacuum treatment ovens with incorporated quench tank.
  • These ovens generally include a cell equipped with heating and possibly cooling means for the thermal or thermochemical treatment as well as incorporated quenching equipment involving a chamber provided with a quenching tank and communicating with the treatment cell. , by means of a removable and watertight partition, means being further provided for transferring the parts, from the cell to the quench tank and vice versa.
  • the invention possibly provides at least one door thermally insulating mobile closing the tunnel at least on one side of the airlock door, preferably on the side where the parts arrive at the end of treatment.
  • the above-mentioned annular tunnel is interrupted in a sector, of length at least equal to that of the support elements of the parts to be treated, so as to delimit a zone for transferring the parts, this zone transfer located at the right of the interior door of the airlock.
  • two retractable vertical doors are provided, made of a thermally insulating material, to ensure the obturation of the two ends of the annular tunnel, on either side of the transfer area.
  • the cylindrical central volume delimited by the annular tunnel is equipped with cooling means, intended to permanently evacuate the heat energy dissipated inside by the annular tunnel, in particular during the opening of the doors and by the parts being in the transfer area at the end of the treatment.
  • the processing means equipping the annular tunnel can be distributed uniformly along this tunnel. They can also consist of a succession of autonomous elements which can be controlled separately by means of a programmable system, in particular to allow custom processing of the parts. These means of this treatment may consist of means of heating by radiation and / or of means of treatment by ion bombardment. In the latter case, a series of electrodes is then provided, namely a series of anodes carried by the tunnel and a series of cathodes which may consist of the support elements on which the parts to be treated are arranged. These cathodes are supplied by means of a circuit electric with rotating joint or, by means of a circular track mounted on the rotating floor and on which come to wear brushes.
  • This furnace therefore makes it possible to carry out all types of treatment by ionic bombardment such as nitriding, oarbonitriding, boriding, various cementations, metallic deposits, etc.
  • thermochemical treatment oven The advantage of the heat or thermochemical treatment oven described above is obvious: first of all, the time of use of the installation of the quenching equipment is multiplied by the number of parts contained inside the oven and its profitability is increased.
  • the rotary hearth furnace shown in these drawings firstly comprises a sealed enclosure 1 connected to means, not shown, for producing inside the enclosure a treatment atmosphere, for example a relative channel.
  • This enclosure 1 comprises a substantially cylindrical vertical side wall 2 as well as a top 3 and a curved bottom. The assembly rests on a base 5 produced in a conventional manner.
  • the enclosure 1 has double walls between which a cooling fluid can circulate in a conventional manner.
  • Access to the interior of the enclosure 1 is carried out by means of an airlock 6 mounted against the vertical wall 2 outside the enclosure 1, which is part of the furnace quenching installation.
  • the airlock 6 comprises, giving on the outside, a conventional pivoting door 7 and, giving on the inside of the enclosure 1, a laterally retractable door 8. It communicates in its lower part with a quenching tank 9 located below the airlock 6.
  • a transfer means 10 allows the transfer of the parts from the outside to the inside of the enclosure 1 and vice versa, as well as immersion parts at the end of treatment in the quench tank 9.
  • a circular raceway 11 is produced on the bottom of the enclosure 1 in a peripheral region substantially adjacent to the cylindrical side wall 2.
  • this raceway 11 is an annular tunnel 12, made of a thermally insulating material, open at its lower face, facing the raceway 11, and equipped with processing means suitable for the use of the furnace, such as electrical resistors 13, electrodes for ion bombardment, nozzles for injection of treatment gas, etc.
  • This tunnel 12 is also interrupted in a sector 14 of about 60 to 70 °, adjacent to the door 8 of the airlock b, which serves as a transfer area.
  • the two openings of this tunnel can be closed respectively by two thermally insulating doors 15, 16, which can take at least two positions, namely, a retracted position in the central part 17 of the enclosure 1, position obtained by horizontal radial translation, and a slightly raised position, obtained by vertical translation.
  • the displacements of these doors are obtained by means of a pulley slide system 19 and return cables 20 driven by a motor 21 located outside the enclosure 1.
  • the lower part of the tunnel 12 is also closed by a rotating floor 22 consisting of a crown of thermally insulating material mounted on the raceway 11 by means of rollers 23 and driven in rotation by means of a motor 24 and a transmission system comprising a pinion 25 meshing with a ring gear 26 secured to the sole 22.
  • This sole 22 carries a series of radial support elements ae S 1 and S 9 intended to carry the loads to be treated, at the rate of three support elements S per load.
  • the floor 22 is designed to carry 9 loads making between them an angular difference of 40 °.
  • the invention also provides a system cooling consisting of a coil 28, housed in the cylindrical volume 17 delimited by the tunnel 12 and connected to an external coolant circuit.
  • a load is introduced and / or extracted from the support elements S located in the transfer zone 14, by the transfer means 10 equipping the airlock 6.
  • the charges thus introduced are then entrained by the floor 22 and circulate inside the tunnel 12 in a forward movement step by step.
  • the maximum duration of treatment of these charges corresponds to the time of passage of the charges inside the tunnel 12. In all cases, the return of the charges in the transfer zone takes place at the end of the final treatment phase .
  • the transfer device 10 which equips the airlock 6, comes to extract the load which has just arrived in the transfer zone 14 and is still at the final treatment temperature, then plunges it into the quench tank 9. At the end of 'quenching operation, the load is extracted from the airlock 6 and the transfer device 10, can receive a new load.
  • the charge transfer zone 14 can correspond to the length of the charges to be treated. In this case there is provided between the loads a sufficient interval to allow the passage of the shutter doors 15 and 16.
  • the sole 22 can then be animated with a stepwise movement whose pitch corresponds to the angular difference between two charges.
  • the doors 15, 16 are controlled so as to close the end of the tunnel 12, at least during each of the stop periods of sole 22.
  • the sole comprises nine groups each comprising three support elements S 1 ) to S 9 , each of these groups being designed to support a load.
  • the distribution of these groups of support elements S is such that the loads are substantially contiguous and are angularly offset by 40 °.
  • the transfer area extends over approximately 70 ° with a central area of 40 ° in the axis of the airlock.
  • This transfer zone 14 therefore partially covers two groups of consecutive support elements S 4 and S 5 arranged symmetrically with respect to the axis of the airlock 6, as shown in FIG. 2.
  • the movement of the sole is no longer a simple step-by-step movement, but a pilgrim's step movement, comprising a movement of recoil of the sole 22 by 20 ° making it possible to bring a group of support elements S, loaded or not on the central area 30, and then a forward movement of 60 °, so that the result of these two movements corresponds to a forward movement of 40 °.
  • the doors 15 and 16 will be retracted in the case of the passage of a support group S, provided with a load, or simply lifted in the case of the passage of a support group S without load.
  • the doors will be retracted in the case where a load is in their path or completely closed in the case where a group of empty support elements S is in their path. In the latter case, the doors 15 and 16 will pass between two consecutive support elements S.
  • the invention is not limited to the embodiments described above.
  • access to the interior of the tunnel from the quenching tank could be effected either by means of the watertight door of the quenching tank and / or by a heat shield parallel to this door.
  • the internal wall of the tunnel will only be interrupted for a possible door (15 or 16) isolating the hot zone from the part which has just received the new load.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Metallurgy (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Materials Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Organic Chemistry (AREA)
  • Tunnel Furnaces (AREA)
  • Vertical, Hearth, Or Arc Furnaces (AREA)
  • Furnace Details (AREA)
  • Manufacture And Refinement Of Metals (AREA)
  • Muffle Furnaces And Rotary Kilns (AREA)
  • Heat Treatments In General, Especially Conveying And Cooling (AREA)
EP83400814A 1982-04-27 1983-04-25 Drehherdofen zur thermischen, thermochemischen oder elektrothermischen Behandlung von Metallen in verdünnter Atmosphäre Expired EP0093060B1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT83400814T ATE21967T1 (de) 1982-04-27 1983-04-25 Drehherdofen zur thermischen, thermochemischen oder elektrothermischen behandlung von metallen in verduennter atmosphaere.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8207224 1982-04-27
FR8207224A FR2525751A1 (fr) 1982-04-27 1982-04-27 Four a sole tournante pour le traitement thermique, thermochimique ou electrothermique de metaux sous atmosphere rarefiee

Publications (2)

Publication Number Publication Date
EP0093060A1 true EP0093060A1 (de) 1983-11-02
EP0093060B1 EP0093060B1 (de) 1986-09-03

Family

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Family Applications (1)

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EP83400814A Expired EP0093060B1 (de) 1982-04-27 1983-04-25 Drehherdofen zur thermischen, thermochemischen oder elektrothermischen Behandlung von Metallen in verdünnter Atmosphäre

Country Status (4)

Country Link
EP (1) EP0093060B1 (de)
AT (1) ATE21967T1 (de)
DE (1) DE3365808D1 (de)
FR (1) FR2525751A1 (de)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0272353A1 (de) * 1985-03-11 1988-06-29 Robert W. Hailey Einrichtung zur Erwärmung und Behandlung bei Verfahren zum Formen von Metallpulver
US4813381A (en) * 1985-04-30 1989-03-21 Gotaverken Energy Systems Ab Controlling thermal transmission rate at a fast fluidized bed reactor
WO2009047211A1 (de) * 2007-10-05 2009-04-16 Loi Thermprocess Gmbh Drehherdofen
WO2009100791A1 (de) * 2008-01-14 2009-08-20 Loi Thermprocess Gmbh Vorrichtung und verfahren zum be- und entladen eines wärmebehandlungsofens
WO2009121326A2 (de) * 2008-04-01 2009-10-08 Manfred Husslein Industrieofen sowie verfahren zum betrieb eines industrieofens
CN101644532B (zh) * 2009-06-26 2011-05-04 中冶长天国际工程有限责任公司 一种回转窑窑头旋转门
CN104864721A (zh) * 2014-10-17 2015-08-26 合肥强安精工装备技术有限公司 工业窑炉
CN110514017A (zh) * 2019-08-28 2019-11-29 大同新成新材料股份有限公司 一种碳碳复合材料的防氧化涂层热处理设备及其方法
CN112985052A (zh) * 2021-04-09 2021-06-18 江西科技学院 一种隧道式连续烧结炉及其烧结方法

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113549974B (zh) * 2021-09-22 2021-12-07 南通铭朗建筑机械有限公司 建筑机械配件加工的局部氧化镀膜处理装置

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3219327A (en) * 1962-02-05 1965-11-23 Heurtey Sa Heating and heat treatment furnace for metal products and ingots
FR1483242A (fr) * 1966-06-13 1967-06-02 Toyo Kogyo Company Ltd Four pour traitement thermique
US3718324A (en) * 1971-11-12 1973-02-27 Hayes Inc C I Vacuum furnace and work cart for use therein
GB2026663A (en) * 1978-07-26 1980-02-06 Hayes Inc C Continuous Heat Treating Vacuum Furnace

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3219327A (en) * 1962-02-05 1965-11-23 Heurtey Sa Heating and heat treatment furnace for metal products and ingots
FR1483242A (fr) * 1966-06-13 1967-06-02 Toyo Kogyo Company Ltd Four pour traitement thermique
US3718324A (en) * 1971-11-12 1973-02-27 Hayes Inc C I Vacuum furnace and work cart for use therein
GB2026663A (en) * 1978-07-26 1980-02-06 Hayes Inc C Continuous Heat Treating Vacuum Furnace

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0272353A1 (de) * 1985-03-11 1988-06-29 Robert W. Hailey Einrichtung zur Erwärmung und Behandlung bei Verfahren zum Formen von Metallpulver
US4813381A (en) * 1985-04-30 1989-03-21 Gotaverken Energy Systems Ab Controlling thermal transmission rate at a fast fluidized bed reactor
WO2009047211A1 (de) * 2007-10-05 2009-04-16 Loi Thermprocess Gmbh Drehherdofen
WO2009100791A1 (de) * 2008-01-14 2009-08-20 Loi Thermprocess Gmbh Vorrichtung und verfahren zum be- und entladen eines wärmebehandlungsofens
US8298474B2 (en) 2008-01-14 2012-10-30 Loi Thermprocess Gmbh Device and method for loading and unloading a heat treatment furnace
WO2009121326A2 (de) * 2008-04-01 2009-10-08 Manfred Husslein Industrieofen sowie verfahren zum betrieb eines industrieofens
WO2009121326A3 (de) * 2008-04-01 2009-12-23 Manfred Husslein Industrieofen sowie verfahren zum betrieb eines industrieofens
CN101644532B (zh) * 2009-06-26 2011-05-04 中冶长天国际工程有限责任公司 一种回转窑窑头旋转门
CN104864721A (zh) * 2014-10-17 2015-08-26 合肥强安精工装备技术有限公司 工业窑炉
CN110514017A (zh) * 2019-08-28 2019-11-29 大同新成新材料股份有限公司 一种碳碳复合材料的防氧化涂层热处理设备及其方法
CN110514017B (zh) * 2019-08-28 2024-05-17 大同新成新材料股份有限公司 一种碳碳复合材料的防氧化涂层热处理设备及其方法
CN112985052A (zh) * 2021-04-09 2021-06-18 江西科技学院 一种隧道式连续烧结炉及其烧结方法

Also Published As

Publication number Publication date
FR2525751A1 (fr) 1983-10-28
EP0093060B1 (de) 1986-09-03
FR2525751B1 (de) 1984-08-17
DE3365808D1 (en) 1986-10-09
ATE21967T1 (de) 1986-09-15

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