EP0206873A1 - Wärmebehandlungsverfahren, Gasabdichtungsvorrichtung und dessen Verwendung in Wärmebehandlungsöfen - Google Patents

Wärmebehandlungsverfahren, Gasabdichtungsvorrichtung und dessen Verwendung in Wärmebehandlungsöfen Download PDF

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Publication number
EP0206873A1
EP0206873A1 EP86401150A EP86401150A EP0206873A1 EP 0206873 A1 EP0206873 A1 EP 0206873A1 EP 86401150 A EP86401150 A EP 86401150A EP 86401150 A EP86401150 A EP 86401150A EP 0206873 A1 EP0206873 A1 EP 0206873A1
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Prior art keywords
gas
oven
inert
hood
heat treatment
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EP86401150A
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English (en)
French (fr)
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EP0206873B1 (de
EP0206873B2 (de
Inventor
Vincent Guillaume
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Air Liquide SA
LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude
Original Assignee
Air Liquide SA
LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude
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Application filed by Air Liquide SA, LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude filed Critical Air Liquide SA
Priority to AT86401150T priority Critical patent/ATE39501T1/de
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Publication of EP0206873B1 publication Critical patent/EP0206873B1/de
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D99/00—Subject matter not provided for in other groups of this subclass
    • F27D99/0073—Seals
    • F27D99/0075—Gas curtain seals
    • 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
    • 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
    • F27B9/045—Furnaces with controlled atmosphere
    • 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
    • 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
    • F27B9/20—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 substantially straight path tunnel furnace
    • F27B9/24—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 substantially straight path tunnel furnace being carried by a conveyor
    • F27B9/243—Endless-strand conveyor

Definitions

  • the present invention relates to a method of heat treatment of objects in a continuous oven comprising at least one heat treatment zone, method in which an atmosphere of non-reactive gas is created under the treatment conditions, at one at least of the ends of said treatment area.
  • the ovens are generally continuous and open at their ends. They include an entry zone for the objects to be heat treated, a heat treatment zone as well as generally a cooling zone, and an exit zone for the objects.
  • the oven has a system for advancing objects to the heat treatment zone, the temperature of the objects gradually increasing as they advance into the oven.
  • the object When the treatment is finished, the object generally crosses a cooling zone in which it is cooled to a temperature such that no oxidation of this object will occur in the ambient air.
  • the required heat treatment atmosphere is supplied to the furnace via endothermic or exothermic generators or by direct injection of suitable liquid-gas mixtures.
  • the injection of this atmosphere is generally carried out in the heat treatment zone or close to it. It is necessary to carry out an overpressure of the atmosphere-generating gas at its injection point in order to try to avoid the return in the furnace of the oxidizing species contained in the air.
  • the system described in this patent also makes it possible to avoid the gaseous atmosphere of the oven from being ejected from the oven and to mix with the ambient air, which leads, of course, to reducing the amount of gas injected into the treatment oven for a specified time interval.
  • the suction system allows the air-inert gas mixture to be evacuated before it can enter the heat treatment zone of the oven.
  • the inlet and outlet areas of the oven comprise a plurality of curtains arranged parallel to each other defining a plurality of chambers into which an inert gas such as nitrogen is injected.
  • This injection is carried out through a perforated wall situated above and / or below said chambers. Nitrogen injection at through these perforated walls is effected by means of a conduit in front of which is placed a deflector, the gas bypassing the latter before entering through the perforations in said chambers.
  • the method according to the invention avoids this drawback.
  • said atmosphere of non-reactive gas is created by a substantially homogeneous curtain of gas, injected into a plane traversed by the direction of advance of the parts to be treated, the injection of non-reactive gas s performing under conditions such that a substantially laminar flow regime is maintained over the entire height of the non-reactive gas curtain.
  • the substantially homogeneous gas curtain is generated at each end of the furnace, the pressure losses induced by these being different from each other, so as to modify the relative value of the gas flows in inlet and outlet of the oven.
  • the use of the method according to the invention allows in particular the zoning of heat treatment furnaces.
  • the presence of the homogeneous curtain of inert gas at one and / or the other end of the furnace makes it possible, depending on the modulation of the flows of neutral gas injected into each curtain, to modify in a distinct manner the conditions of exit of the gases at each end of the furnace, and this in a significant way compared to the pressure losses imposed on the moving gas inside the furnace.
  • this injection point When there is a gas injection point at a higher pressure than that of the gases injected at other points, this injection point will direct the gas flow rates in the furnace. If it is located towards the entrance of the oven, the gas flow will be the same as the direction of advance of the parts. Conversely, if it is located near the outlet of the oven, the gas flow will be in the opposite direction to the direction of advance of the parts in the oven.
  • the zone at maximum pressure of the furnace can be better located in the desired location, in the case of a plurality of injections at different points without thereby increasing the flow rates of the active gases.
  • non-reactive gas used in the present application obviously means an inert or non-reactive gas with respect to the other constituents of the atmosphere of the oven as well as the parts which must be treated in it.
  • nitrogen is used as the non-reactive gas, although in some cases it is preferable to use argon or possibly helium.
  • active gas designates the gas or gases from the heat treatment atmosphere.
  • the earth “heat treatment” includes all the heat treatments that are usually subjected to metals, ceramics, etc., but is particularly intended for the annealing of metal parts such as stainless steel.
  • heat treatment zone means one or more parts of the oven in which heating means are optionally arranged, in which identical or different atmospheres are created, each atmosphere preferably being homogeneous. It also includes the case where the heat present in this zone comes from the part itself which enters the heat treatment zone to undergo a transformation such as hot rolling, etc.
  • the method according to the invention can be used in all continuous ovens of the horizontal or vertical type.
  • the conditions of uniformity imposed on the inert gas curtains are such that the entry and / or exit zones provided with homogeneous gas curtains according to the invention must be located in non-vertical parts of the oven.
  • the non-reactive gases as well as the reactive gases intended for the heat treatment of the parts are injected directly into the heat treatment zone of the furnace, or in the vicinity thereof. It is however possible to introduce these gases into part of the cooling zone or possibly into or near the zone of entry into the furnace. In all cases, the use of the method according to the invention will make it possible to direct the flow of these gases towards the interior of the furnace and achieve zoning thereof.
  • the method according to the invention is characterized in that said atmosphere of inert or non-reactive gas is created by a stream of inert gas injected vertically at the inlet of the substantially homogeneous furnace, according to a laminar flow regime with a flow rate equal to the air flow entering the oven in the absence of injection of inert gas.
  • the air enters the oven, through phenomena of natural convection, through the lower part of the inlet zone, because this air is much colder than the out of the oven.
  • the curtain of inert or non-reactive gas is injected from top to bottom, the presence of curtains, preferably refractory, on either side of the gas curtain, is necessary, these curtains are 'extend substantially to the conveyor belt of objects in the oven.
  • the use of the process according to the invention proves to be particularly effective when the continuous furnaces comprise an inlet zone of short length and / or a significant temperature difference between the gases leaving the oven and the ambient temperature (for example, a temperature difference greater than 300 ° C)
  • the homogeneous curtain of inert gas will be created using a hood making it possible to maintain the flow of non-reactive gas in laminar and substantially hamgene regime at all points of the gas curtain.
  • the curtains used in this hood will preferably take the form of those described in the American patent cited above, this form of curtains made up of a plurality of elements of different weights being better adapted in particular to ovens in which objects of different forms are treated.
  • the material constituting said curtains must be on the one hand without action on the flow of non-reactive gas from the hood and on the other hand must resist the temperatures to which it is subjected.
  • sintered materials such as materials of the rock wool, quartz wool, or glass wool type, having a thickness of at least two centimeters , were particularly suitable in this application.
  • the inlet chamber of the inert or non-reactive gas generally has a rectangular shape, the base of which is formed by the perforated plate. It has been found that the best results of continuity and uniformity of the gas curtain were obtained when the height of this intake chamber was at least twice the thickness of the material permeable to neutral gas. In this way, the pressure gradients and therefore the turbulence inside this intake chamber are practically avoided.
  • the means for injecting the inert gas into the intake chamber will generally be in communication with the latter on the face opposite to its perforated face. It was found that it was preferable to have the arrival of neutral gas substantially in the center of this plate, so as to create symmetry in the injection of said neutral gas.
  • the inert gas supply channel is connected to the intake chamber by means of a pre-admission chamber which is substantially symmetrical about the axis of arrival of the inert gas.
  • the connection zone between this preadmission chamber and the intake chamber will be constituted by means permeable to neutral gas identical in their nature and structure to those described above.
  • the invention also relates to the use of the method in a heat treatment oven, comprising a hood as defined above, at least at the inlet and / or the outlet thereof.
  • This hood will preferably be arranged with its intake chamber placed above the parts to be treated. It is also possible to place this hood in the lower part of the oven.
  • the perforated plate of the intake chamber will be opposite the passage of the objects to be treated, while the curtains which allow the confinement of the flow of homogeneous laminar gas will be suspended from the upper part of the oven.
  • a hood placed in the upper part of the oven and provided with its curtains, while a second intake chamber is placed in the lower part of the oven so as to that the flow of inert gas leaving the perforated plate of this second chamber is located between the curtains of the upper hood.
  • a hood at each end of the oven, the pressure of inert gas injected into each of the hoods being different, the pressure losses induced by each curtain of gas being different from each other, so as to modify the relative value of the gas flows entering and leaving the furnace. It is thus possible to orient the flow of said heat treatment gases in the desired direction relative to the direction of advance of the parts to be treated. In particular, it is possible to direct the flow of gases against the current in the direction of advance of the parts, according to the type of heat treatment to which said parts are subjected. In some cases, this pressure difference may result in the absence of injection of inert gas into one of the hoods.
  • a heat treatment furnace is shown diagrammatically comprising successively an inlet zone H 1 followed by the hot heat treatment zone HZ, followed by a cooling zone CZ at the end of which is the zone H 2 outlet.
  • the injection of heat treatment gas takes place at the point GI substantially in the zone of separation of the hot zone HZ and the cooling zone CZ.
  • the curves shown above the schematic view of this furnace show the pressure on the ordinate and the distance from the point considered with respect to the inlet zone of the furnace on the abscissa.
  • the curve CI represents the pressure variations of the heat treatment gas injected at point GI for a conventional open furnace according to the prior art.
  • the maximum pressure of the heat treatment gas is located in GI, point of injection of this gas, the pressure of the gas, which moves away on the one hand towards the hot zone and on the other hand towards the cooling zone, being equal in zones H1 and H2 to atmospheric pressure.
  • Curve C 3 shows the pressure profile in the oven after having placed a homogeneous inert gas curtain according to the invention at the ends thereof. The pressure is then kept maximum at the gas injection points to decrease to a value which remains above atmospheric pressure at near the inlet and / or outlet areas of the oven.
  • the process according to invention in a preferred embodiment, is characterized by one of the following relationships: or
  • Pt maxi or Pf maxi are of the order of 10 -1 to 10 -4 Pascal above atmospheric pressure.
  • FIG. 2 represents a schematic view of an open furnace with a stainless steel annealing mat, according to the invention.
  • This oven successively comprises an inlet hood H 1 described in more detail below, a zone for introducing IZ of the parts to be treated, of length L 1 , a heat treatment zone HZ, of length L 2 , then a zone cooling unit CZ, of length L 3 which ends in a hood H 2 identical to the hood H l .
  • Different gas injection points are provided in particular substantially in the middle of the cooling zone CZ, the injection point GI ,, at the limit of the cooling zones CZ and of the heat treatment HZ, the injection point GI 2 , at the entrance to the HZ heat treatment zone the GI 3 injection point and at the entrance to the IZ zone the GI 4 injection point.
  • Figure 3 shows on its part 3A a front view and on its part 3B a sectional view of a hood according to the invention. It consists of a supply channel 100 of inert gas connected to the inlet of the preadmission chamber 103.
  • the latter of substantially cylindrical shape, of diameter substantially equal to that of the height of the zone 107 of the chamber intake (see below) comprises two zones having substantially the same volume, a first zone 120, followed for a second zone delimited by two perforated plates 101, 102 between which is disposed a rock wool mattress 104.
  • the wall perforated 102 opens into the intake chamber 105 of substantially parallelepiped shape.
  • the admission chamber 105 is bordered laterally by walls 111 and 112 as well as 121 and 122. Towards the lower part of said walls 111 and 112 are located two fixing strips 115, 116 parallel to said walls to which are hung two refractory curtains 113, 114. The height of these curtains is such that they come into contact with the conveyor belt for advancing objects in the oven.
  • FIG. 4 represents different possibilities of fixing the hoods in an oven, the same elements as those of the preceding figures bearing the same references.
  • Figure 4A shows schematically a hood fixed in the upper part of the oven
  • Figure 4B shows a hood fixed in the lower part of the oven
  • Figure 4C shows a variant with two diffusion chambers and a single pair of curtains.
  • 150 and 151 respectively represent the upper and lower walls of the furnace.
  • the refractory curtains 113 and 114 extend substantially to the bottom wall 151 of the oven.
  • the refractory curtains 113, 114 are fixed by their fixing strips 115, 116 to the upper wall 150 of the furnace, while the expansion chamber 205 (identical to the chamber 105 previously described) is fixed to the lower wall 151 of the oven, the perforated plate of said chamber 105 being of course oriented towards the upper wall 150 of the oven.
  • the gas is injected into the chamber 205 via the pipe 203, the ends of the curtains 113 and 114 arriving substantially at the level of the perforated wall of the chamber 205.
  • FIG. 4C shows a variant with a single pair of curtains and two intake chambers 105 and 205 respectively.
  • the relative arrangements of the two chambers 105 and 205, substantially identical to each other, are such that the refractory curtains 113 and 114 in a vertical position surround the intake chamber 205, so as to maintain the gas injected through the pipes 103 and 203 between said curtains 113 and 114.
  • the example below relates to a continuous open furnace for annealing steel pipe.
  • the atmosphere used in this annealing furnace has substantially the following composition: 10% of H 2 , 8% of CO, 4% of CO 2, 78 of N 2 (by volume), dew point: approximately 0 ° C.
  • This oven has a P.H.Z. 3.50 meters in length followed by a heat treatment area at around 900 ° C. In the preheating zone, the steel tubes are gradually brought to the temperature of the hot zone.
  • FIG. 5 illustrates, using the curves J 1 and J 2 respectively , the ratio of the concentrations of carbon dioxide and carbon monoxide as a function of the distance in the furnace relative to the inlet zone.
  • a hood having the structure shown in FIG. 3 with the dimensions given below had been installed at the inlet of the oven, the outlet of the latter taking place directly on the ambient atmosphere.
  • Curve J 1 represents the ratio of CO / C0 2 concentrations in the absence of a homogeneous laminar flow of nitrogen in the hood, while curve J 2 represents the same concentration ratio with a homogeneous and laminar flow of nitrogen between the refractory curtains of said hood.
  • This example was carried out using the furnace shown in FIG. 2.
  • the oven is an open oven with stainless steel annealing mat.
  • the different atmospheres injected at points GI 1 , GI 2 , GI 3 , GI 4 of the oven are shown in the table below:
  • Figure 6 shows the hydrogen concentrations in the furnace.
  • Curve D l represents the hydrogen concentration in the oven in the absence of a hood
  • curve D 2 represents the hydrogen concentration in the oven using the method according to the invention, summarized in the table above.
  • the GI 2 injection point is located at the limit of the heat treatment heating zone and the furnace cooling zone. According to the invention, the hydrogen is almost exclusively directed to the cooling zone of the furnace. The parts taken out of the oven show no trace of oxidation.
  • Curve D 1 (oven without hood) shows that, practically over the entire length of the hot zone HZ of the treatment oven, (4 meters in this example), there is a significant concentration of hydrogen. This varies from approximately 25% at the injection point (7 meters from the entry area) to approximately 1% at 3 meters from the entry area of the oven. In the middle of this hot zone, there is a concentration of about 10% in hydrogen.
  • Curve D 2 (oven with hoods according to the invention) shows that the hydrogen concentration is of the order of 1% at about 6 meters from the inlet of the oven, 3/4 of the hot zone not having d 'hydrogen.
  • the hydrogen concentration profile with or without a hood in the CZ cooling zone is substantially identical.
  • This example shows the possibilities of precise zoning of heat treatment furnaces using the method according to the invention.
  • This example was carried out in the furnace of FIG. 1.
  • the heat treatment zone HZ was at a temperature of 800 ° C., with an injection of gas at the point GI at the limit between the hot zone HZ and the cooling zone CZ .
  • a hood was placed only at the inlet H 1 of the hot zone, no hood being arranged at the outlet.
  • the atmosphere injected is identical to that of Example 1, an atmosphere well known to those skilled in the art for the annealing of steel strips.
  • FIG. 7A represents the concentration of carbon dioxide in the atmosphere of the furnace respectively without hood (El) and with hood (E2), as a function of the abscissa of the measurement point in the furnace relative to the inlet thereof. this.
  • the CO 2 concentration at the inlet of the oven is substantially identical to that of the atmosphere injected into the oven, which shows the absence of entry of oxidizing species into the oven using the process according to the invention.
  • the curves F 1 and F 2 of FIG. 7B represent the variations of the dew point in ° C in an oven respectively without hood and with hood relative to the abscissa of the measurement point thereof relative to the input .
  • the dew point is significantly lowered, with a hood (curve F 2 ) which is substantially identical in both cases 8 meters from the oven entrance. Consequently, the concentration of H 2 0, oxidizing experiment, in the furnace using the process according to the invention is also kept constant until the inlet of the furnace.
  • the flow rate of neutral gas in the hoods was 2.5 m 3 / hour.
  • FIG. 8 illustrates a preferred embodiment of the method according to the invention, requiring at least two points for injecting gas into the treatment oven.
  • This variant is characterized by equal pressures at the injection points GI and G'.I '. from the oven.
  • this alternative embodiment is applied to the furnace of FIG. 2, choosing to inject GI 2 gas. and GI 3 . only, that is to say at the entry and exit of the hot zone HZ, this will have the characteristics of the zone CD described above.
  • the following relationships concerning pressures are:
  • zone CD can be preserved while carrying out other gas injections into the oven in the zones BC and DE of the oven, at a pressure below Pt max and Pf max .
  • FIGS. 9A and 9B represent a preferred variant of the invention in which a curtain of inert or inactive gas (N 2 in the figure) is used at the entrance only to the oven.
  • the oven has been shown diagrammatically, seen in section, only at its inlet 303 and its outlet 304.
  • a hood 305 provided with refractory curtains 306 and 307, such as 'illustrated in Figures 3 and 4, this hood being integral with the upper part 301 of the oven.
  • the refractory curtains have their lower end located near the lower part 302 of the oven, generally provided with a conveyor belt for advancing objects such as 308.
  • a distance of the order of a few centimeters between the lower end of the curtains 306 and 307 and the lower part 302 of the oven is well suited in practice. No particular device is placed at the outlet 304 of the oven.
  • inert or inactive gas generally nitrogen
  • measurements are made at the curtains 306 and 307, in the absence nitrogen injection, the air flow that enters the oven by natural convection phenomena. This measurement is carried out using a hot wire, in a manner known per se.
  • FIG. 9B the same elements as those in FIG. 9Aa have the same references.
  • the hood 305 is placed, in this variant, in the lower part of the oven, without refractory curtains.
  • the nitrogen flow is adjusted as described above. It is noted as above that the air arriving near the inlet of the oven does not penetrate into it but is entrained upwards by the current of atmosphere leaving the upper part of the inlet of the oven.
  • the use of the method illustrated in FIG. 9 makes it possible to reduce the flow rates of atmosphere used in the heat treatment furnaces, whatever the number and the nature of the gas injection points therein, for its rate of oxygen determined in the hot zone of the oven.
  • a continuous oven having an inlet area of 2m, a hot area at 800 ° C of 5m and a water cooling zone of 10m, as well as an inlet section of approximately . 0.2m 2 , consumed when its two ends were open 100 Nm 3 / h of nitrogen to achieve a protective atmosphere intended for the annealing of copper parts.
  • the air speed is measured at l entry of the oven, in the absence of nitrogen in the hood. This is 37 cm / s.
  • Nitrogen is then injected at 37 years / s into said hood, which corresponds to a flow rate of 30 Nm 3 / h of nitrogen.
  • the nitrogen flow in the oven can then be reduced to 20 Nm 3 / h, for an identical quantity of the products at the out of the oven. There is therefore an overall reduction of 50% in the nitrogen flow rates in this furnace.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Organic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Heat Treatments In General, Especially Conveying And Cooling (AREA)
  • Furnace Details (AREA)
  • Heat Treatment Of Strip Materials And Filament Materials (AREA)
  • Tunnel Furnaces (AREA)
  • Solid-Phase Diffusion Into Metallic Material Surfaces (AREA)
  • Powder Metallurgy (AREA)
  • Processing And Handling Of Plastics And Other Materials For Molding In General (AREA)
  • Waste-Gas Treatment And Other Accessory Devices For Furnaces (AREA)
  • Drying Of Solid Materials (AREA)
EP86401150A 1985-06-05 1986-05-30 Wärmebehandlungsverfahren, Gasabdichtungsvorrichtung und dessen Verwendung in Wärmebehandlungsöfen Expired - Lifetime EP0206873B2 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT86401150T ATE39501T1 (de) 1985-06-05 1986-05-30 Waermebehandlungsverfahren, gasabdichtungsvorrichtung und dessen verwendung in waermebehandlungsoefen.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8508470A FR2583064B1 (fr) 1985-06-05 1985-06-05 Procede de traitement thermique, hotte pour la mise en oeuvre de ce procede et son utilisation dans les fours de traitement thermique
FR8508470 1985-06-05

Publications (3)

Publication Number Publication Date
EP0206873A1 true EP0206873A1 (de) 1986-12-30
EP0206873B1 EP0206873B1 (de) 1988-12-28
EP0206873B2 EP0206873B2 (de) 1992-07-08

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EP86401150A Expired - Lifetime EP0206873B2 (de) 1985-06-05 1986-05-30 Wärmebehandlungsverfahren, Gasabdichtungsvorrichtung und dessen Verwendung in Wärmebehandlungsöfen

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US (1) US4746289A (de)
EP (1) EP0206873B2 (de)
JP (1) JP2665333B2 (de)
KR (1) KR870000438A (de)
AT (1) ATE39501T1 (de)
AU (1) AU587256B2 (de)
BR (1) BR8602604A (de)
CA (1) CA1277214C (de)
DE (1) DE3661542D1 (de)
ES (2) ES8708018A1 (de)
FR (1) FR2583064B1 (de)
ZA (1) ZA864139B (de)

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US5409159A (en) * 1994-02-28 1995-04-25 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Apparatus and methods for inerting solder during wave soldering operations
US5411200A (en) * 1994-02-28 1995-05-02 American Air Liquide, Inc. Process and apparatus for the wave soldering of circuit boards
US5520320A (en) * 1994-04-22 1996-05-28 Air Liquide America Corporation Process for wave soldering components on a printed circuit board in a temperature controlled non-oxidizing atmosphere
IL119434A (en) * 1995-11-27 2000-01-31 Boc Group Inc Furnace
DE69930330T2 (de) * 1998-03-26 2006-08-24 Jfe Steel Corp. Durchlaufwärmebehandlungsofen
EP1914325B1 (de) * 2005-07-25 2013-09-11 Nippon Steel & Sumitomo Metal Corporation Kontinuierliche wärmebehandlung von metallrohren
JP5029974B2 (ja) * 2010-01-21 2012-09-19 富山住友電工株式会社 金属多孔体及びそれを用いた電池用電極、並びに金属多孔体の製造方法
CN103305744B (zh) * 2012-03-08 2016-03-30 宝山钢铁股份有限公司 一种高质量硅钢常化基板的生产方法
CN118127453B (zh) * 2024-05-08 2024-07-05 运城市山海机械设备制造有限公司 一种压球机机芯压辊制造用渗氮设备及其操作方法

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FR2068909A5 (de) * 1969-11-03 1971-09-03 Btu Eng Corp
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US3467366A (en) * 1967-10-02 1969-09-16 Hayes Inc C I Furnace construction having atmosphere curtain
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EP0075438B1 (de) * 1981-09-19 1987-12-16 BOC Limited Wärmebehandlung von Metallen

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ES557554A0 (es) 1987-10-16
EP0206873B1 (de) 1988-12-28
AU587256B2 (en) 1989-08-10
ZA864139B (en) 1987-02-25
JP2665333B2 (ja) 1997-10-22
US4746289A (en) 1988-05-24
ES555695A0 (es) 1987-09-01
ES8800412A1 (es) 1987-10-16
KR870000438A (ko) 1987-02-18
DE3661542D1 (en) 1989-02-02
CA1277214C (fr) 1990-12-04
EP0206873B2 (de) 1992-07-08
JPS6237317A (ja) 1987-02-18
ATE39501T1 (de) 1989-01-15
BR8602604A (pt) 1987-02-03
ES8708018A1 (es) 1987-09-01
AU5832786A (en) 1986-12-11
FR2583064A1 (fr) 1986-12-12
FR2583064B1 (fr) 1987-08-14

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