DE742433C - Device for avoiding warping when quenching steel or metal strips in a quenching bath - Google Patents

Device for avoiding warping when quenching steel or metal strips in a quenching bath

Info

Publication number
DE742433C
DE742433C DEK164485D DEK0164485D DE742433C DE 742433 C DE742433 C DE 742433C DE K164485 D DEK164485 D DE K164485D DE K0164485 D DEK0164485 D DE K0164485D DE 742433 C DE742433 C DE 742433C
Authority
DE
Germany
Prior art keywords
rollers
quenching
pair
bath
steel
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.)
Expired
Application number
DEK164485D
Other languages
German (de)
Inventor
Walter Koerner
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.)
WALTER KOERNER
Original Assignee
WALTER KOERNER
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 WALTER KOERNER filed Critical WALTER KOERNER
Priority to DEK164485D priority Critical patent/DE742433C/en
Application granted granted Critical
Publication of DE742433C publication Critical patent/DE742433C/en
Expired legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B45/00—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
    • B21B45/02—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills for lubricating, cooling, or cleaning
    • B21B45/0203—Cooling
    • B21B45/0209—Cooling devices, e.g. using gaseous coolants
    • B21B45/0215—Cooling devices, e.g. using gaseous coolants using liquid coolants, e.g. for sections, for tubes
    • B21B45/0218—Cooling devices, e.g. using gaseous coolants using liquid coolants, e.g. for sections, for tubes for strips, sheets, or plates
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B45/00—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
    • B21B45/02—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills for lubricating, cooling, or cleaning
    • B21B45/0203—Cooling
    • B21B45/0209—Cooling devices, e.g. using gaseous coolants
    • B21B45/0215—Cooling devices, e.g. using gaseous coolants using liquid coolants, e.g. for sections, for tubes
    • B21B45/023—Cooling devices, e.g. using gaseous coolants using liquid coolants, e.g. for sections, for tubes by immersion in a bath
    • 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
    • C21D1/62—Quenching devices
    • C21D1/63—Quenching devices for bath quenching
    • 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
    • C21D9/573—Continuous furnaces for strip or wire with cooling
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
    • B21B1/22—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length
    • B21B1/24—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length in a continuous or semi-continuous process
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B13/00—Metal-rolling stands, i.e. an assembly composed of a stand frame, rolls, and accessories
    • B21B13/02—Metal-rolling stands, i.e. an assembly composed of a stand frame, rolls, and accessories with axes of rolls arranged horizontally
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B13/00—Metal-rolling stands, i.e. an assembly composed of a stand frame, rolls, and accessories
    • B21B13/02—Metal-rolling stands, i.e. an assembly composed of a stand frame, rolls, and accessories with axes of rolls arranged horizontally
    • B21B2013/025—Quarto, four-high stands
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B13/00—Metal-rolling stands, i.e. an assembly composed of a stand frame, rolls, and accessories
    • B21B13/02—Metal-rolling stands, i.e. an assembly composed of a stand frame, rolls, and accessories with axes of rolls arranged horizontally
    • B21B2013/028—Sixto, six-high stands
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B2265/00—Forming parameters
    • B21B2265/02—Tension
    • B21B2265/06—Interstand tension

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Heat Treatment Of Strip Materials And Filament Materials (AREA)

Description

Vorrichtung zur Vermeidung von Verwerfungen beim Abschrecken von Stahl-oder Metallbändern in einem Abschreckbad Das Vergüten von endlosen Bändern aus Stahl- und Metallegierungen im Durchlaufverfahren erfolgt durch Erhitzen des Bandes in einem Durchlaufofen oder ähnlicher Einrichtung und anschließendem Abschrecken in einer Kühlflüssigkeit. Beim Abschrecken der Bänder treten Verwerfungen auf, die sich in Beulen oder Wellen zeigen.Device to avoid warping when quenching steel or Metal strips in a quenching bath The quenching and tempering of endless strips made of steel and metal alloys in a continuous process is done by heating the strip in a continuous furnace or similar device and subsequent quenching in a coolant. When the strips are quenched, distortions occur that show up in bumps or waves.

Das Abschrecken wird bisher allgemein derartig vorgenommen, daß das Band nach dem Verlassen des Härteofens über eine Rolle oder eine Leiste in einen Abschreckbehälter geführt wird. Durch das Einführen des heißen Bandes in die Albschreckflüssigkeit entstehen Wallungen des Bades, die ein ungleichmäßiges Abschrecken und Verwerfungen des-Bandes zur Folge haben. Zur Vermeidung dieser Verwerfungen sind Vorrichtungen bekannt, die aus zwei Platten bestehen, zwischen denen das Band hindurchgezogen wird. Die obere Platte ist hierbei durch Gewichte belastet. Die Platten liegen im Abschreckbehälter und werden von der Kühlflüssigkeit umspült. Diese Vorrichtung hat den Nachteil, daß die Kühlflüssigkeit das Band, soweit es von den Platten belegt ist, nicht allseitig umspülen kann. Ein Teil der im Band enthaltenen Wärme muß auf dem Umwege über die Platten an die - Kühlflüssigkeit abgegeben werden. Da das Band beim Durchgang zwischen den Platten aber bereits eine sehr hohe Festigkeit hat, wird eine ebene Bandfläche nur unvollkommen oder .gar nicht erreicht. Durch das Durchziehen des Bandes durch die Platten wird außerdem die Bandoberfläche sehr leicht beschädigt, und- der Kraftbedarf zum Durchziehen des Bandes wird unverhältnismäßig hoch.The quenching has so far generally been carried out in such a way that the After leaving the hardening oven, the tape is fed into a roller or bar Quenching container is performed. By inserting the hot band into the fright liquid there are surges in the bath that cause uneven quenching and warping des tape result. There are devices to avoid these distortions known, which consist of two plates, between which the tape is pulled will. The top plate is loaded with weights. The plates are in Quenching tank and are washed around by the coolant. This device has the disadvantage that the cooling liquid covers the tape as far as it is occupied by the plates cannot wash around on all sides. Some of the heat contained in the tape must be the detour via the plates to the - cooling liquid. Because the tape but already has a very high strength when passing between the plates, a flat belt surface is only imperfectly or not at all achieved. By the Pulling the tape through the plates also makes the surface of the tape very light damaged, and the force required to pull the tape through is disproportionate high.

Die vorliegende Erfindung vermeidet diese Nachteile dadurch, daß sie aus mehreren hintereinander angeordneten Walzengerüsten besteht, deren Walzen ganz oder teilweise von der Kühlflüssigkeit umspült werden. Zwischen den Walzen wird das Band unter regelbarem Druck hindurchgezogen. Da die Umfangsgeschwindigkeit eines nachgeschalteten Walzenpaares gleich oder größer ist als die Durchziehgeschwindigkeit des Bandes, entsteht hierdurch eine Streck- und Glättwirkung. Die Walzen berühren das Band nur linienförmig, so daß die Kühlflüssigkeit ungehindert die gesamte Bandoberfläche bespülen kann. Zweckmäßig wird das erste Walzengerüst so angeordnet, daß die Berührungslinien zwischen Walzen und Band im Abschreckbereich liegen, d. h. bevor z. B. bei Bandstahl der Stahl seine volle Härte erreicht hat. Um dieses zu erreichen, wird der Walzendurchmesser des ersten Walzenpaares möglichst gering gewählt. Die Walzen können außerdem so angeordnet werden, daß das Band über eine am Ofenausgang befindliche Leiste oder Rolle umgeführt und unter den Flüssigkeitsspiegel des Abschreckbehälter: getaucht wird, oder aber, daß das Band ohne Umführung am Ofenaustritt unmittelbar zwischen die Walzen geführt wird. Bei diesem unmittelbaren Eintritt des Bandes in die Walzen, also bei gestrecktem Durchlauf des Bandes durch den Ofen und die Vergütungseinrichtung, wird die Kühlflüssigkeit hinter dem ersten bzw. weiteren Walzengerüst durch dauernden Zufluß so hoch gehalten, dar das Band dauernd unter dem Flüssigkeitsspiegei liegt. Vor dein ersten Walzengerüst und hinter dem letzten Walzengerüst wird der Flüssigkeitsspiegel durch geeignete Abflüsse unter der Bandrlurchlaufabene gehalten. Zwischen den einzelnen Walzenpaaren kann durch geeignete Einrichtungen sowohl die Badhöhe, als auch die Badtemperatur geregelt werden.The present invention avoids these disadvantages in that they consists of several roll stands arranged one behind the other, the rolls of which are completely or are partially washed around by the coolant. Between the rollers is the tape under adjustable Pressure pulled through. As the peripheral speed of a downstream pair of rollers is equal to or greater than the pull-through speed of the tape, this creates a stretching and smoothing effect. Touch the rollers the belt only linearly, so that the cooling liquid unhindered the entire belt surface can wash. The first roll stand is expediently arranged so that the lines of contact lie between the rollers and the strip in the quenching area, d. H. before z. B. with strip steel the steel has reached its full hardness. To achieve this, the roller diameter is used of the first pair of rollers selected as low as possible. The rollers can also do so be arranged that the tape over a bar located at the furnace exit or Roll circulated and below the liquid level of the quenching tank: submerged is, or that the tape without bypassing at the furnace outlet directly between the rollers is guided. With this direct entry of the strip into the rollers, i.e. when the strip runs straight through the furnace and the tempering device, the cooling liquid is continuous behind the first or further roll stand The inflow is kept so high that the band is permanently below the liquid level. The liquid level is in front of your first roll stand and behind the last roll stand kept below the belt flow rate by suitable drains. Between each Roller pairs can be both the bath height, as well as the Bath temperature can be regulated.

In der Zeichnung sind zwei Ausführungsformen der Vorrichtung im Anschluß an einen Durchlaufglühofen dargestellt, und zwar zeigt A,bb. i einen Längsschnitt der Vorrichtung bei Urnführu.ng des Bandes am Ofenauslauf über eine Leiste, Abb. 2 einen Längsschnitt der Vorrichtung bei gestrecktem Durchlauf des Bandes ohne Umführung am Ofenaustritt.In the drawing, two embodiments of the device are in connection shown on a continuous annealing furnace, namely shows A, bb. i a longitudinal section of the device when guiding the belt at the furnace outlet over a bar, Fig. 2 shows a longitudinal section of the device with the strip running straight through without bypassing at the furnace outlet.

Das endlose Glühgut a tritt aus dein Durchlaufofen b aus, wird in _ Abb. i über eine Leiste c umgelenkt und tritt unterhalb des Flüssigkeitsspiegels zwischen die Walzend des ersten Walzengerüstes e. f sind die Stützwalzen zur Erhöhung des Widerstandsmomentes der Walzen d. ei und e. zeigen die nachgeschalteten Walzengerüste mit den Walzenpaaren d1 und d.. Eine oder mehrere Umwälzpumpen sorgen in Verbindung mit Kühl- oder Heizregistern für den dauernden Umlauf der Abschreckflüssigkeit zwischen den einzelnen Walzenpaaren.The endless annealing material a emerges from the continuous furnace b, is deflected in _ Fig. I over a bar c and occurs below the liquid level between the roller ends of the first roller stand e. f are the back-up rollers to increase the section modulus of the rollers d. ei and e. show the downstream roll stands with the roll pairs d1 and d .. One or more circulating pumps in connection with cooling or heating registers ensure the constant circulation of the quenching liquid between the individual roll pairs.

In der Abb. 2 tritt das endlose Glühgut a unmittelbar zwischen die Walzen d des ersten Walzengerüstes e. Der Flüssigkeitsspiegel zwischen dem ersten, dem zweiten und den weiteren Walzengerüsten liegt über der Glüh-:gut;lurchlaufe`uene und vor dem ersten und hinter dem letzten Walzengerüst unter der Glühgutdurchlaufebene.In Fig. 2, the endless annealing material a occurs directly between the Rolling d of the first roll stand e. The liquid level between the first, the second and the further roll stands are above the annealing: good; and in front of the first and behind the last roll stand under the annealing material flow level.

Claims (5)

PATENTANSPRÜCHE: i. Vorrichtung zur Vermeidung von Verwerfungen beim Abschrecken von Stahl- oder Metallbändern in einem Abschreckbad, gekennzeichnet durch mehrere hintereinander angeordnete Walzenpaare, die ganz oder teilweise von der Abschreckflüssigkeit umspült werden, und zwischen denen das Bad unter Ausübung eines Zuges in der Längsrichtung hindurchgeführt wird. PATENT CLAIMS: i. Device to avoid warping when Quenching of steel or metal strips in a quenching bath, marked by several pairs of rollers arranged one behind the other, wholly or partially from the quenching liquid is washed around, and between which the bath is exercised a train is passed through in the longitudinal direction. 2. Vorrichtung nach Anspruch i, dadurch gekennzeichnet, daß die Umfangsgeschwindigkeit eines Walzenpaares gleich oder kleiner ist als diejenige des in Förderrichtung benachbarten Walzenpaares. 2. Device according to claim i, characterized in that the peripheral speed of a pair of rollers is the same or is smaller than that of the adjacent pair of rollers in the conveying direction. 3. Vorrichtung nach Anspruch i und 2, dadurch gekennzeichnet, daß die Berührungslinie des ersten Walzenpaares hinter dem Ofen mit dem Band gleichzeitig die Berührungsgrenze des Bandes mit der Abschreckflüssigkeit bildet. 3. Apparatus according to claim i and 2, characterized in that the contact line of the first pair of rollers behind the furnace with the belt at the same time the contact limit of the tape forms with the quenching liquid. 4. Vorrichtung nach Anspruch i bis 3, dadurch gekennzeichnet, daß Mittel zum Regeln der Höhe und Temperatur der zwischen den einzelnen Walzenpaaren befindlichen Abschreckflüssigkeit vorgesehen sind. 4. Apparatus according to claim i to 3, characterized in that means for regulating the height and temperature of the between the individual roller pairs located quenching liquid are provided. 5. Vorrichtung nach Anspruch i bis 4, dadurch gekennzeichnet, daß die Berührungswalzen des ersten Walzenpaares den kleinstmöglichen Durchmesser erhalten und zwischen Stützwalzen gelagert sind. Zur Abgrenzung des Anmeldungsgegenstandes vom Stand der Technik sind im Erteilungsverfahren folgende Druckschriften in Betracht gezogen worden: deutsche Patentschrift ..... 1 r. 674 278; britische Patentschriften \r. io 69911893, 125 180; USA.-Patentschriften .... Nr. 2 139 483, 1981411.5. Apparatus according to claim i to 4, characterized in that the contact rollers of the first pair of rollers have the smallest possible diameter and are mounted between support rollers. To distinguish the subject of the application from the state of the art, the following publications were considered in the granting procedure: German patent specification ..... 1 r. 674 278; British patents \ r. io 69911893, 125 180; USA. patents .... no. 2,139,483, the 1,981,411th
DEK164485D 1942-04-25 1942-04-25 Device for avoiding warping when quenching steel or metal strips in a quenching bath Expired DE742433C (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
DEK164485D DE742433C (en) 1942-04-25 1942-04-25 Device for avoiding warping when quenching steel or metal strips in a quenching bath

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DEK164485D DE742433C (en) 1942-04-25 1942-04-25 Device for avoiding warping when quenching steel or metal strips in a quenching bath

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DE742433C true DE742433C (en) 1943-12-07

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3313024A1 (en) * 1983-04-12 1984-10-18 Babcock-BSH AG vormals Büttner-Schilde-Haas AG, 4150 Krefeld Method and device for quenching passing steel sheets, in particular thick or medium sheets, with simultaneously controlled alignment

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB125180A (en) * 1900-01-01
US1981411A (en) * 1932-06-16 1934-11-20 Krupp Ag Grusonwerk Annealing and pickling plant
US2139483A (en) * 1935-07-02 1938-12-06 Badlam Stephen Method of rolling flat material
DE674278C (en) * 1933-12-30 1939-04-13 Bethlehem Steel Corp Process to reduce the tendency to bend errors and warping in sheet metal or strips made of steel

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB125180A (en) * 1900-01-01
US1981411A (en) * 1932-06-16 1934-11-20 Krupp Ag Grusonwerk Annealing and pickling plant
DE674278C (en) * 1933-12-30 1939-04-13 Bethlehem Steel Corp Process to reduce the tendency to bend errors and warping in sheet metal or strips made of steel
US2139483A (en) * 1935-07-02 1938-12-06 Badlam Stephen Method of rolling flat material

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3313024A1 (en) * 1983-04-12 1984-10-18 Babcock-BSH AG vormals Büttner-Schilde-Haas AG, 4150 Krefeld Method and device for quenching passing steel sheets, in particular thick or medium sheets, with simultaneously controlled alignment

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