US3827854A - Automatic metal protecting apparatus and method - Google Patents

Automatic metal protecting apparatus and method Download PDF

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Publication number
US3827854A
US3827854A US00410220A US41022073A US3827854A US 3827854 A US3827854 A US 3827854A US 00410220 A US00410220 A US 00410220A US 41022073 A US41022073 A US 41022073A US 3827854 A US3827854 A US 3827854A
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Prior art keywords
furnace
chamber
strip
protective gas
rate
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US00410220A
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English (en)
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W Gildersleeve
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Individual
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Individual
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Priority to US00410220A priority Critical patent/US3827854A/en
Priority to GB185574A priority patent/GB1413944A/en
Priority to CA190,115A priority patent/CA1002151A/en
Priority to ZA740351A priority patent/ZA74351B/xx
Priority to AU64614/74A priority patent/AU483064B2/en
Priority to FR7403650A priority patent/FR2249170B1/fr
Priority to BE140579A priority patent/BE810642A/xx
Priority to IT9340/74A priority patent/IT1005371B/it
Priority to DE2406029A priority patent/DE2406029C3/de
Application granted granted Critical
Publication of US3827854A publication Critical patent/US3827854A/en
Assigned to FIRST PENNSYLVANIA BANK N A, A NATIONAL BANKING ASSOCIATION reassignment FIRST PENNSYLVANIA BANK N A, A NATIONAL BANKING ASSOCIATION SECURITY INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: SELAS CORPORATION OF AMERICA A CORP OF PA
Assigned to SELAS CORPORATION OF AMERICA A CORP. OF PA reassignment SELAS CORPORATION OF AMERICA A CORP. OF PA RELEASED BY SECURED PARTY (SEE DOCUMENT FOR DETAILS). Assignors: FIRST PENNSYLVANIA BANK N.V., FOR ITSELF AND AS AGENT FOR THE PHILADELPHIA NATIONAL BANK
Assigned to BANCBOSTON FINANCIAL COMPANY reassignment BANCBOSTON FINANCIAL COMPANY SECURITY INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: SELAS CORPORATION OF AMERICA
Assigned to SELAS CORPORATION OF AMERICA reassignment SELAS CORPORATION OF AMERICA RELEASED BY SECURED PARTY (SEE DOCUMENT FOR DETAILS). Assignors: BANCBOSTON FINANACIAL COMPANY A MA TRUST
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    • 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
    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/52—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for wires; for strips ; for rods of unlimited length
    • C21D9/54—Furnaces for treating strips or wire
    • C21D9/56—Continuous furnaces for strip or wire
    • C21D9/561—Continuous furnaces for strip or wire with a controlled atmosphere or vacuum
    • 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
    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/52—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for wires; for strips ; for rods of unlimited length
    • C21D9/54—Furnaces for treating strips or wire
    • C21D9/56—Continuous furnaces for strip or wire

Definitions

  • ABSTRACT When a metal strip passing through a furnace is overheated, the furnace is automatically shut down in a special way to prevent outside air from rushing in to cause strip oxidation in critical furnace areas.
  • the fuel-air mixture in the furnace is gradually reduced to a low rate which is substantially above zero, and then continues at that low rate for a definite period of time.
  • a non-oxidizing gas such as nitrogen is gradually introduced into the furnace at a gradually increasing rate, reaching its full flow after a definite period of time, while maintaining positive pressure in the furnace chamber.
  • exhaust stack dampers which are initially open, as required automatically to maintain positive furnace pressure, are gradually and automatically brought to a closed position to assist in preventing outside air from being drawn into the furnace chamber.
  • the present invention relates to strip metal heating, and more particularly to a method and apparatus for controlling a strip heating furnace to prevent harm to the strip due to overheating or oxidation.
  • the strip In the continuous heating of metal strip for annealing and galvanizing or other purposes, the strip is pulled through a furnace chamber in front of open burners. When, for some reason, the strip slows down or stops, the burners have usually been quickly throttled to a minimum or shut off quickly in order to prevent damage to the strip by oxidation, overheating, or otherwise.
  • a cooling gas of a non-oxidizing type be introduced into the furnace to reduce the temperature of the strip and of the furnace refractory lining below a value that causes harm to the strip. Further, in performing this operation, it is highly desirable to prevent excessive oxidation of the strip surface. When the strip is to be galvanized, substantially all oxidation must be prevented if possible.
  • any sudden reduction of pressure in the direct fired portion of the furnace when communicated to the connected horizontal heat treating chamber, immediately causes a sudden reduction of pressure to below atmospheric pressure in the horizontal heat treating chamber, inducing outside air to leak through small unsealable openings in the horizontal heat treating chamber to contaminate the protective atmosphere, causing oxidation and damage to the metal.
  • the initial cooling while the strip is decelerated to a stop is provided by a non-oxidizing cooling medium in the lower portion of the furnace.
  • the upper portions are cooled with air, an oxidizing medium.
  • Modern strip heating furnaces have been developed to such an extent that the strip can be heated rapidly to a predetermined temperature.
  • One type of a difficulty occurs when the strip is slowed down below a minimum operating speed, or is stopped.
  • the furnace temperature must be reduced rapidly to prevent the strip from being burned through, or heated to such an extent that it breaks of its own weight, or tears or breaks when it is subjected to the stresses of the startup operation.
  • the atmosphere of the furnace must be controlled so that excessive oxidation does not take place.
  • FIG. 1 is a diagrammatic view in side elevation showing a portion of a strip heating furnace and a connected horizontal heat treating chamber illustrating certain features of this invention
  • FIG. 2 is a schematic diagram showing the arrangement of the automatic control means comprising one embodiment in accordance with this invention.
  • FIG. 3 is an electrical diagram illustrating the time sequence of operations in accordance with one embodiment of this invention.
  • the strip 1 is passed over guide rolls 2 and 3 to travel downwardly in a vertical path through furnace 4.
  • the furnace may be of the type shown in the U.S. Pat. No. 2,869,846 to Bloom or the U.S. Pat. No. 3,320,085 to Turner, for example. It is provided with radiant cup-type burners 5 which face the strip and fire directly into the furnace chamber. Products of combustion rise in the chamber and are exhausted through ducts 6 at the top of the furnace and are conducted to the stack 6'.
  • the furnace through which the strip travels is maintained at a minimum critical temperature, and the fuelair ratio is controlled to provide the necessary reducing character of the gases (products of combustion) for effecting proper heating and final strip clean-up.
  • the fuel-air ratio of the furnace is regulated to provide a slight excess of fuel so that there is no free oxygen in the furnace atmosphere, and so that there are from 3 percent to 6 percent combustibles in the form of carbon monoxide and hydrogen.
  • the strip When the strip leaves the furnace, it has a clean surface suitable for producing an adherent coating that must be protected.
  • the strip upon leaving the furnace, the strip passes through a throat 7, around a bottom roll 10 and to and through a horizontal treating chamber 9 that is filled with a protective atmosphere which can be neutral or reducing.
  • the delivery end or snout 23 of this horizontal treating chamber 9 is below the level ofthe molten zinc 11 in pot 12.
  • Suitable guide rolls 13 are provided to guide the strip through the horizontal treating chamber 9.
  • Horizontal treating chamber 9 is preferably insulated and may have conventional provisions for heating and/or cooling so that the strip passing through it will be brought to the desired coating temperature. Metals other than zinc, such as aluminum for example, may be used in the pot 12.
  • the strip may be heated in horizontal treating chamber 9, using radiant tubes 14.
  • a protective gas such as nitrogen or a mixture of nitrogen with a small percentage of hydrogen, is usually introduced into the chamber 9, preferably at various points designated in the drawing as HNX.
  • the top of the furnace chamber is slightly open at 16 to provide an entry slot for the strip 1.
  • Air bars 20, 20 are provided above and to each side of the opening 16.
  • Each air bar 20 is an elongated pipe and has a plurality of spaced air jets which are aimed obliquely downwardly into the entry slot 16 in a manner to impede the flow of gases upwardly from the furnace chamber, outwardly through the opening 16.
  • the number 21 represents a damper in duct 6, which normally controls furnace chamber pressures and is opened and closed by a damper operator, usually in the form of a cylinder 22.
  • the damper 21 is centrally mounted in duct 6, and swings adjustably about its shaft 6(a) and thus controls furnace chamber pressures. It is opened and closed by the air cylinder 22 operating the shaft 6(a) through a mechanical linkage. Damper 21 increases furnace back pressure when it is closed. It is, however, incapable of forming a perfect seal when closed, since leakage space is present all around the edge of the damper in order to allow for expansion.
  • Typical leakage areas include the hearth roll shafts 13 (which extend through chamber 9), access doors, threading doors, bolted and clamped connections, the snout 23 which corrodes in contact with molten zinc, and light and sight ports.
  • the timing and rate of introduction of the cooling gas and of the fuel and air to the burners are controlled in a critical manner to maintain a positive pressure in the furnace chamber throughout the entire shutdown procedure. This is accomplished, in essence, by avoiding a simultaneous introduction of cooling gas and shutting off of the fuel and air to the burners.
  • the cooling gas is only gradually introduced, with gradual increase of rate of introduction and the flow of fuel and air is reduced gradually to a predetermined low rate, which is maintained at a constant rate for a period of time. After the cooling gas flow has reached a steady rate and has continued at such rate for a definite period of time, the flow of fuel and air is shut off.
  • a relay is incorporated into the operating circuit of the equipment which controls the running of the strip through the furnace.
  • This relay is energized when the line is in the Run" condition as opposed to a .log" or Thread condition.
  • the strip line is intended to run at normal production speeds under control of the line opera- I01, and the furnace IS started Lin anautomatically 56- Valve A4 Nitrogen quench (bottom of Furnace Closed 7' quenced cycle.
  • this relay' is de-energized the furnace is shut down in an automatically sequenced. cycle.
  • Valve Bl Zone i.
  • Burner Air Shut-Off Closed Valve B2 Zone 1 (Fuel) Gas ShutOff Closed Valve V Re is a re 'ulatin i valve which main- It IS an inherent characteristic of a furnace heating tuins ii proger fuel-tfi-air hint.
  • Valve B3 Zone 2 Nitrogen for hurner cooling Open Stnp .that there is a low Speed point at which i i 1m Valve Cl Zone 2.
  • a contact is incorporated into cal sequencediagram for a furnace of a configuration the control system of the line, which contact is autoas shown in FIG. I and with valves as shown in FIG. 2: matically closed at speeds below the speed at which the In this diagram 011 line 19 a relay (llne P lightest gauge strip can be processed.
  • This relay IS principally operated by the speeds the line is automatically stopped and the furstrip moving mechanism and is energized when the nace is shut down in an. automatically sequenced cycle, l5 strip moving n m y
  • the deenerglzmg 0f thlS relay when the strip temperature sensor 15 detects an overcauses the moving strip to come to a stop. temperature condition as the. strip leaves the direct A l y n P ay) 1S Shown m lme fi d ti f th f 23; which when energized causes the furnace stop se
  • valves A1,A3-,A4, B1, B2, B3and (Lme 22) tggz gyf C1 are arranged so that, when an electrical signal is ap- (Line 3), (Line 4) plied the valves open at a controlled rate, and when the (Linc l d h l l t n d S-8 (Line 21) Open (these all open on sigtna IS mterrupte t e va ves c ose at a con ro e line stoppage) ra e.
  • the furnace light-off sequence IS as follows (the time alve itrogen quenc ottom o urnace ose Zone l) (opened only on line stop for approxcycle 5 Selecte'd as an mpi y and vanes wlth imately three niinutes) Furnace and line characteristics), see FIG. 3.
  • Valve B3 closes and Valve Cl is opens. energized and opens. (Switch b-3 of valve B3, line 14 closes) (Zone 2 lights on minimum). 12 seconds 5-3 on Line 4 Valve A5 opens. (Zone 2 goes closes. on temperature control) 14 seconds 5-4 on Line l0 Valves BI and B2 open.
  • Timer TD 2 is reset.
  • Valve A2 opens 16 seconds 5-6 on Line 3 Valve A2 opens. (Zone I goes on closes temperature control) 7 58 seconds 5-8 on Line 22 Timer is stopped.
  • Time Delay Relays TD3F on line 16 and TD3S on line 16A are energized and begin timing.
  • Relay RC is energized and its contact in line 6 closes, energizing nitrogen purge valves A3 and A4 on lines 6 and 7.
  • the purge timer on line 5 is also energized.
  • timer TD3F times out (approximately 5 seconds) its contact on line 24 closes and the furnace Stop Relay F.S.R. on line 23 is energized to initiate the furnace stop sequence.
  • timer TD3S times out (approximately l seconds) its contact on line 19 opens to deenergize the Line Stop Relay L.S.R. on line 19 to stop strip movement.
  • furnace start sequence timer motor M resets by running for two seconds and returns all start contacts S-l -8 to their initial positions, as heretofore outlined.
  • the timer TDl which was energized when the relay CR contact closed, may be set for approximately a period of 3 minutes, after which it gradually closes valves A3 and A4, shutting off the nitrogen quench.
  • valve Al controlling the air bleed to the flue 6 has fully opened and the furnace pressure control damper 21 moves under the influence of the furnace pressure controller to its new position to maintain a positive pressure.
  • Time delay relay TD2 operates to shut off the air and gas to Zone 1 completely with gradual movement of valves B1 and B2, and gradually to open the nitrogen valve B3.
  • a limit switch opens to cause the combustible mixture supply valve C1 to close.
  • the introduction of nitrogen into the Zone 2 burner nozzles serves to maintain a burner pressure to prevent backfire, and to keep the burner tips from overheating.
  • timer contact TD4F on line 25 closes to energize the furnace stop relay F.S.R. on line 23 and initiate furnace shutdown. Five seconds later, TD4S contact on line 19 opens to stop strip movement.
  • timer TD3F on line 16 timer TD3S on line 16(a) and a relay RC on line 15 are energized.
  • the relay contact (line 6) of relay RC closes to energize valves A3 and A4, thus admitting nitrogen quench to the furnace, A-3 at the bottom of Zone 1 and A-4 at the bottom of Zone 1.
  • Time delay relay TD3F is set to delay for 5 seconds, for example, and then shuts down the furnace by energizing relay F.S.R. on line 23.
  • relay TD3S contact in line 19 opens 5 seconds later, deenergizing relay L.S.R. on line 19 to stop strip movement.
  • the time of shutting down the furnace after pressing the stop button and the further time delay for strip travel are adjustable by simply adjusting the settings of time delay relays TD3F, TD3S, TD4F and TD4S.
  • valves that are used in controlling the flow rates of fuel and air into the burners, and of protective gas into the zones of the furnace chamber are carefully constructed so that they do not open or close instantaneously.
  • means are deliberately introduced into the valves to limit the rate at which they can open or close.
  • the speed of operation of the valve is limited by inserting an orifice plate of predetermined size into the air line which leads to the diaphragm chamber.
  • valves A2 and A5 that control fuel and air to the burners move gradually toward thier minimum fire positions, causing a gradual reduction of feed rate for a considerable period of time (2-5 seconds, for example).
  • valves A3 and A4 controlling the introduction of cooling gas open gradually and slowly, gradually increasing the feed rate of the gas for a considerable period of time (2-5 seconds, for example).
  • the protective gas may be introduced at various periods of time before the fuel or air valves are actuated. Further, the rates of movement of the control valves may be varied, provided the pressure in the furnace chamber is maintained above atmospheric pressure.
  • Other changes in the specific form, arrangement and sequencing of the electrical and control elements shown in FIGS. 2 and 3 may be made, and equivalent elements may be substituted, parts may be reversed, and certain features may be used independently of others, all without departing from the spirit and scope of this invention as defined in the appended claims.
  • steps (a) through (e) are automatically actuated in response to sensing the strip temperature, the temperature of actuation being above a predetermined temperature.
  • step (c) occurs prior to step (a).
  • said chamber includes a passageway for exhaust gases, which passageway has an opening provided with a controllable closure for said opening, the step which comprises closing said opening during the introduction of said protective gas into said chamber.
  • said furnace chamber has an outlet that is in communication with a strip treating chamber containing a protective gas and also having openings to the atmosphere, the step of maintaining the pressure in said furnace chamber higher than the'pressure in said strip treating chamber to prevent any substantial inward flow of said atmosphere into the protective gas in said chamber.
  • an apparatus for heat treating metal strip which apparatus includes a furnace having a chamber containing a plurality of burners, the fuel feed to which is valve controlled, means for passing said strip through said furnace, and means for introducing a protective gas into the furnace chamber, an automatic sequence control having a turning device connected to actuate said control valve for reducing the rate of fuel to the burners, time delay means and means for introducing said protective gas into said furnace chamber after a predetermined time delay, and in response to said time delay means.
  • thermosensor means is arranged in the vicinity of the strip exit from the chamber, and wherein said temperature sensing means is calibrated to actuate said control valve to initiate a reduction of said rate of feed of fuel.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Heat Treatment Of Strip Materials And Filament Materials (AREA)
  • Tunnel Furnaces (AREA)
  • Furnace Details (AREA)
US00410220A 1973-10-26 1973-10-26 Automatic metal protecting apparatus and method Expired - Lifetime US3827854A (en)

Priority Applications (9)

Application Number Priority Date Filing Date Title
US00410220A US3827854A (en) 1973-10-26 1973-10-26 Automatic metal protecting apparatus and method
GB185574A GB1413944A (en) 1973-10-26 1974-01-15 Method and apparatus for preventing oxidation of a metal strip during heating
CA190,115A CA1002151A (en) 1973-10-26 1974-01-15 Method and apparatus for preventing oxidation of a metal strip during heating
ZA740351A ZA74351B (en) 1973-10-26 1974-01-17 Method and apparatus for preventing oxidation of a metal strip during heating
AU64614/74A AU483064B2 (en) 1973-10-26 1974-01-17 Method and apparatus for preventing oxidation ofa metal strip during heating
FR7403650A FR2249170B1 (show.php) 1973-10-26 1974-02-04
BE140579A BE810642A (fr) 1973-10-26 1974-02-05 Procede et appareil pour empecher l'oxydation d'une bande metallique durant la chauffe
IT9340/74A IT1005371B (it) 1973-10-26 1974-02-07 Apparecchiatura automatica e meto do per proteggere da ossidazione na stri metallici riscaldati ed altro
DE2406029A DE2406029C3 (de) 1973-10-26 1974-02-08 Verfahren und Anlage zur Verhinderung der Oxydation und/oder Überhitzung eines Metallbandes bei der Wärmebehandlung in einem Durchlaufofen

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Application Number Priority Date Filing Date Title
US00410220A US3827854A (en) 1973-10-26 1973-10-26 Automatic metal protecting apparatus and method

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US3827854A true US3827854A (en) 1974-08-06

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US00410220A Expired - Lifetime US3827854A (en) 1973-10-26 1973-10-26 Automatic metal protecting apparatus and method

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US (1) US3827854A (show.php)
BE (1) BE810642A (show.php)
CA (1) CA1002151A (show.php)
DE (1) DE2406029C3 (show.php)
FR (1) FR2249170B1 (show.php)
GB (1) GB1413944A (show.php)
IT (1) IT1005371B (show.php)
ZA (1) ZA74351B (show.php)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3940235A (en) * 1974-08-26 1976-02-24 Xerox Corporation Immersion fusing
US3984197A (en) * 1972-03-25 1976-10-05 Hoechst Aktiengesellschaft Device for the wet treatment and drying of textile material
US3984198A (en) * 1972-02-23 1976-10-05 Hoechst Aktiengesellschaft Device for the impregnation and drying of textile material
US3985498A (en) * 1972-06-21 1976-10-12 Hoechst Aktiengesellschaft Process and device for drying chemical products
US4148946A (en) * 1977-02-14 1979-04-10 Armco Steel Corporation Method for maintaining a non-oxidizing atmosphere at positive pressure within the metallic strip preparation furnace of a metallic coating line during line stops
US4183983A (en) * 1978-08-17 1980-01-15 Selas Corporation Of America Method for reducing metal oxide formation on a continuous metal sheet in the hot dip coating thereof
US4210097A (en) * 1977-02-14 1980-07-01 Armco Inc. Means for maintaining a non-oxidizing atmosphere at positive pressure within the metallic strip preparation furnace of a metallic coating line during line stops
US4379547A (en) * 1980-04-11 1983-04-12 Nippon Steel Corporation Continuous cold rolling and annealing apparatus for steel strip
EP0233944A4 (en) * 1985-07-18 1988-05-31 Nippon Kokan Kk CONTINUOUS BAND STEEL PROCESSING CHAIN HAVING A DIRECT FLAME TREATMENT OVEN.
US5227142A (en) * 1990-07-30 1993-07-13 Nikkiso Co., Ltd. Production apparatus for vapor-grown fine fibers
US20110171590A1 (en) * 2008-09-22 2011-07-14 I.A.S. Induktions-Anlagen + Service Gmbh & Co. Kg Device for heating rod-type work pieces

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5912729B2 (ja) * 1976-10-27 1984-03-26 新日本製鐵株式会社 竪型直火加熱炉
DE3017978C2 (de) * 1980-05-10 1986-03-13 Daimler-Benz Ag, 7000 Stuttgart Verfahren zur vorübergehenden Stillegung von Durchstoßaufkohlungsanlagen
AT395321B (de) * 1983-07-05 1992-11-25 Ebner Ind Ofenbau Verfahren zum abkuehlen von chargen in diskontinuierlich arbeitenden industrieoefen, insbesondere von stahldraht- oder - bandbunden in haubengluehoefen
DE102009049678B3 (de) * 2009-10-13 2011-04-21 Stefan Kutsche Durchlaufofen für eine Hochtemperaturerwärmung vereinzelter metallischer Elemente oder eines metallischen Strangs
DE102009058642A1 (de) * 2009-12-16 2011-06-22 Ipsen International GmbH, 47533 Verfahren und Einrichtung zur Regelung von Prozessgasen für Wärmebehandlungen von metallischen Werkstoffen/Werkstücken in Industrieöfen

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3448969A (en) * 1968-01-08 1969-06-10 Michigan Oven Co Fluid pressure sealing system for processing oven
US3584851A (en) * 1968-06-18 1971-06-15 Pilkington Brothers Ltd Dampering systems
US3721520A (en) * 1971-09-02 1973-03-20 Selas Corp Of America Galvanizing wire

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3448969A (en) * 1968-01-08 1969-06-10 Michigan Oven Co Fluid pressure sealing system for processing oven
US3584851A (en) * 1968-06-18 1971-06-15 Pilkington Brothers Ltd Dampering systems
US3721520A (en) * 1971-09-02 1973-03-20 Selas Corp Of America Galvanizing wire

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3984198A (en) * 1972-02-23 1976-10-05 Hoechst Aktiengesellschaft Device for the impregnation and drying of textile material
US3984197A (en) * 1972-03-25 1976-10-05 Hoechst Aktiengesellschaft Device for the wet treatment and drying of textile material
US3985498A (en) * 1972-06-21 1976-10-12 Hoechst Aktiengesellschaft Process and device for drying chemical products
US3940235A (en) * 1974-08-26 1976-02-24 Xerox Corporation Immersion fusing
US4148946A (en) * 1977-02-14 1979-04-10 Armco Steel Corporation Method for maintaining a non-oxidizing atmosphere at positive pressure within the metallic strip preparation furnace of a metallic coating line during line stops
US4210097A (en) * 1977-02-14 1980-07-01 Armco Inc. Means for maintaining a non-oxidizing atmosphere at positive pressure within the metallic strip preparation furnace of a metallic coating line during line stops
US4183983A (en) * 1978-08-17 1980-01-15 Selas Corporation Of America Method for reducing metal oxide formation on a continuous metal sheet in the hot dip coating thereof
US4379547A (en) * 1980-04-11 1983-04-12 Nippon Steel Corporation Continuous cold rolling and annealing apparatus for steel strip
EP0233944A4 (en) * 1985-07-18 1988-05-31 Nippon Kokan Kk CONTINUOUS BAND STEEL PROCESSING CHAIN HAVING A DIRECT FLAME TREATMENT OVEN.
US5227142A (en) * 1990-07-30 1993-07-13 Nikkiso Co., Ltd. Production apparatus for vapor-grown fine fibers
US20110171590A1 (en) * 2008-09-22 2011-07-14 I.A.S. Induktions-Anlagen + Service Gmbh & Co. Kg Device for heating rod-type work pieces

Also Published As

Publication number Publication date
ZA74351B (en) 1974-11-27
FR2249170A1 (show.php) 1975-05-23
BE810642A (fr) 1974-08-05
DE2406029B2 (de) 1978-05-18
DE2406029C3 (de) 1979-01-25
CA1002151A (en) 1976-12-21
DE2406029A1 (de) 1975-04-30
AU6461474A (en) 1975-07-17
FR2249170B1 (show.php) 1976-06-25
IT1005371B (it) 1976-08-20
GB1413944A (en) 1975-11-12

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