EP0290523B2 - Discharge and flow regulator for metallurgical vessels and casting process - Google Patents
Discharge and flow regulator for metallurgical vessels and casting process Download PDFInfo
- Publication number
- EP0290523B2 EP0290523B2 EP87907412A EP87907412A EP0290523B2 EP 0290523 B2 EP0290523 B2 EP 0290523B2 EP 87907412 A EP87907412 A EP 87907412A EP 87907412 A EP87907412 A EP 87907412A EP 0290523 B2 EP0290523 B2 EP 0290523B2
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- EP
- European Patent Office
- Prior art keywords
- stopper
- vessel
- aperture
- pouring
- flow
- 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.)
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D41/00—Casting melt-holding vessels, e.g. ladles, tundishes, cups or the like
- B22D41/14—Closures
- B22D41/16—Closures stopper-rod type, i.e. a stopper-rod being positioned downwardly through the vessel and the metal therein, for selective registry with the pouring opening
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
- B22D11/10—Supplying or treating molten metal
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D41/00—Casting melt-holding vessels, e.g. ladles, tundishes, cups or the like
- B22D41/14—Closures
- B22D41/22—Closures sliding-gate type, i.e. having a fixed plate and a movable plate in sliding contact with each other for selective registry of their openings
Definitions
- the invention relates to an outlet and flow control device for a metallurgical melt-receiving vessel, which has an outlet pipe located on the bottom of the vessel with a pouring opening, with a stopper which cooperates with the outlet pipe, the stopper in its closed position inserting one into the bore of the Exhaust pipe protruding, at least approximately cylindrical, serving as shut-off device, which contains at least one radial throttle opening on its circumference, which merges into a longitudinal channel of the pin open at the bottom and between the plug and the outlet pipe above the throttle opening there is a first seal that can be closed by lowering the plug.
- the invention relates to a casting method for pouring molten metal from a metallurgical vessel, which contains at least one outlet opening located on the bottom of the vessel, which cooperates with a stopper to form sealing elements, the melt in the opened stopper position via an at least approximately horizontal outlet opening in the Plug and its longitudinal channel open at the bottom flows out.
- a stopper device in which the outlet opening in the bottom of the vessel can be closed by a stopper in the inside of the vessel, which is fastened to the lower end of a rod.
- the plug can be raised for casting and lowered for closing the spout by means of a lever linkage that can be operated from the outside. Disadvantages are, however, the poor control characteristics of the flow and an unsatisfactory security against closure, for example if there are lugs on the stopper.
- dome-type rotary valves in which an eccentric inlet channel can be brought into communicating connection with an outlet opening by means of a rotary connection.
- This requires high processing and grinding accuracy of the difficult to manufacture spherical separation point between rotating and stationary components.
- the melt tends to freeze in the pouring opening.
- Slider closures are also known attached to the vessel containing the melt.
- the closure bodies sliding on one another under pretension are subject to considerable wear, since the movement of the adjustable part must take place under the influence of the high temperature of the molten metal.
- Another disadvantage is the high purchase and Maintenance costs. In order to ensure sufficient security of the seal, high machining accuracy of the slide plates made of refractory material is required.
- a device for regulating the outlet of melts in which there is a stopper which can be actuated by a linkage from below.
- the plug head is provided with a sealing surface, which forms a seal together with an annular perforated brick.
- the stopper is provided directly adjacent to the sealing surface with a plurality of radial openings which open into a central outlet channel which is open at the bottom.
- the security of the closure is also unsatisfactory because of the risk of build-up or erosion in the closure area. If the seal fails, a melt breakthrough has catastrophic consequences.
- the risk of slag entrainment cannot be eliminated with this closure device, since, together with the trough-shaped depression in the perforated brick, an oblique or even essentially vertical flow forms in the melt.
- There is also a risk of freezing when pouring on since the melt cools rapidly in the trough which is wedge-shaped in cross section. Since the joint between the movable plug and the stationary perforated brick is connected to ambient air at the bottom, air can be sucked in by the vacuum created during casting, which causes undesired reoxidation of the melt.
- DE-A 1 558 285 shows a piston lock for ladles.
- the reciprocating piston is provided with drive means which engage at the bottom and with which a pure axial displacement into the opening and closing position can be effected.
- a radial opening opens into a central flow opening that is open at the bottom. Since a widened head is missing on the reciprocating piston, the seal is limited to the part located above the radial opening of the reciprocating piston together with the perforated brick hole.
- the perforated stone sits in a funnel-shaped recess in the bottom of the pan, which is why no predominantly horizontal direction of flow is formed during pouring, but the suction of the flowing melt will propagate in the upward direction and, as a result, parts of the slag can be entrained.
- the object to be achieved with the invention is to create an outlet and flow control device and a casting method which has a simple, inexpensive to manufacture structure, allows a constant, precise control of the flow of melt, and results in a high level of sealing reliability and at
- the casting process largely avoids the formation of eddies and prevents slag running along the outflowing melt, while maintaining good flow controllability and tightness.
- the device according to the invention with which this object is achieved is characterized in that the stopper is located at the lower end of a vertically movable rod protruding from above into the interior of the vessel, the rod is articulated and has radial play with respect to the stopper neck surrounding it, and the pin between its radial throttle opening and the sealing surface located above it contains a ring part closed on the casing, which together with the adjacent part of the bore forms a second seal.
- the casting method according to the invention is characterized in that the melt is given a predominantly horizontal flow direction in the area near the stopper, and that by changing the angle of rotation of the at least approximately horizontal outlet opening of the stopper, the inflow direction into the stopper is continuously changed during the outflow from the vessel.
- the actuating mechanism By actuating the stopper by means of a rod protruding into the melting vessel from above, the actuating mechanism can be designed extremely easily. There are no moving fixtures beneath the bottom of the melting vessel, which are annoying due to their space requirement and which are endangered in their movement function under the influence of heat and metal splashes. Since the stopper is subjected to pressure in the closing direction, there is a high degree of locking security, in contrast to a stopper actuation from below, in which the closing force requires the stopper to be subjected to tensile stress and the refractory materials - compared to their compressive strength - only have a significantly lower tensile strength to have.
- the plug and the bore in the pouring spout can be precisely manufactured using conventional manufacturing methods. To achieve an effective seal, the plug must fit into the bore of the pouring spout with virtually no play.
- the high-heat-resistant materials used generally have a high compressive strength, but only a low flexural strength. This results in problems with the plug assembly together with the relatively long rod, since if the actuating rod is not exactly aligned with the pin, bending forces occur which would either cause the plug seat to jam or even lead to the plug being broken off. It should also be noted that heat distortion can occur both in the rod and on the vessel under the heat of fusion, which can lead to a slight curvature of the rod and thus to its bending stress, for example.
- a first seal is obtained in a manner known per se, in that, in the closed position, a conical shoulder rests against the edge of the bore of the outflow pipe.
- the breakthrough security for the melt is greatly increased by a second, cumulative sealing device.
- This consists in that a ring part which is closed on the jacket and which forms the second seal together with the bore is present on the pin between its throttle opening and the conical sealing surface located above it.
- This results in improved security against leakage, since the two seals take effect one after the other and only after a stroke movement of the stopper corresponding to the ring width V has been covered.
- Such stopper devices with a reliable sealing function have a longer service life, as a result of which the operating costs can be reduced.
- a good control characteristic for the flow of the melt results from the fact that the amount of molten metal flowing out per unit of time can be adjusted and metered directly by the stroke of the stopper, which in particular makes casting on easier. In this way, conventional sand filling, which results in an undesired admixture, can be dispensed with.
- the largely horizontal direction of flow calms the melt, which favors the elimination of non-metallic inclusions that slowly rise to the surface.
- the melt layer near the bottom of the vessel is removed during casting. This prevents premature slag running above a minimum bath level.
- the largely horizontal flow direction is favored by the radial arrangement of the single throttle opening in the stopper together with the possibility of rotation. Since the horizontal pouring spout can be rotated during the pouring process, the flow conditions of the respective vessel shape, the different bath height, the melt temperature and other parameters can be adjusted from case to case.
- a stopper rod 5 projects into the stopper neck 10, with which the stopper 6 can be moved in the vertical direction and rotated about its axis.
- the drive is effected by a drive device 17 located outside the vessel 1.
- the vertical drive can consist of a mechanical, motor-driven spindle 8 or a hydraulic or pneumatic lifting cylinder.
- a horizontal arm 23 is connected to the vertical guide member 9 above the edge of the vessel. The connection of the arm 23 with the upper end of the plug rod 5 and below with the bell-like plug head 24 takes place by means of a coupling ball 11.
- the plug rod 5 held in the plug neck 10 has radial play.
- the rotary drive device 17 provided for rotating the plug 6 about its vertical axis is connected to a drive motor (not shown in more detail). This motor can be a servo or stepping motor, with which different rotational positions of the plug 6 can be programmed and reproduced. The rotational position of the plug 6 could also be changed by pneumatic or hydraulic rotary drives.
- the plug 6 contains a cylindrical pin 13 which engages in a bore 7 of the outlet channel 4.
- This pin 13 is provided with a horizontal radial throttle opening 14 which opens into an axially open bore part 12 and merges into the pouring channel 4. Since the pin 13 is only open radially on one side, the outflowing metal melt is forced onto a predetermined direction of flow, which is indicated by the line S in FIG. 1.
- the aim is to achieve a flow that is as horizontal as possible in order to prevent eddy formation of the melt and thus slag suction from above.
- the direction of flow can also be influenced step by step or continuously during the casting process.
- the flow cross section of the throttle opening is reduced or completely closed.
- the stopper rod 23 can be fixed with the upper coupling ball 11 of the stopper rod 5 automatically with a clamping device. As a result, the plug rod 5, which can move with play, and the plug 6 located in its lower end need not be precisely aligned before assembly. A stopper neck 10 surrounding the stopper rod 5 serves as protection against the melt. Since the control forces are directed directly into the head of the plug 6 via the plug rod 23, the plug 6 is protected from bending forces by alignment errors. The otherwise usual alignment work for the stopper 6 is dispensed with and the stopper can also be used automatically in hot metallurgical vessels, which results in a reduction in the vessel circulation times and thus maintenance costs are saved.
- the stopper 6 contains a cylindrical or slightly conical spigot 13 projecting into the bore 7 of the pouring tube 3.
- this spigot 13 contains a plurality of radial throttle openings 14. These are evenly distributed on the circumference of the spigot.
- the upper and the lower region of these throttle openings 14 are each wedge-shaped, while the middle region of these throttle openings 14 contains parallel vertical side walls 18.
- the longitudinal axes of the throttle openings 14 extend in the vertical direction, ie in the direction of the stopper movement.
- the throttle openings 14 open into the central longitudinal bore part 15 of the pin 13 which is open at the bottom. Above the throttle openings 14, the pin 13 merges into a frustoconical widening 16, which is a frustoconical Barrier forms.
- the central angle of this shut-off surface forms an angle of 75 ° to 105 °, preferably 90 °. Together with a frustoconical countersink 18 at the upper edge of the bore 7 at the same angle, this results in an annular first seal 20.
- this ring part 19 together with the adjacent cylindrical bore 7 with the same diameter results in a second seal 21.
- the lowermost part of the pin 13 is likewise designed as a ring part 22 closed on the jacket, so that the pin 13 is in the bore 7 remains guided, even if the throttle openings 14 are fully open.
- the plug head 24 is expanded in a bell shape.
- the approximately horizontal lower edge 26 of the widened stopper head 24 is at a relatively large distance from the horizontal surface 28 of the pouring tube 3 projecting beyond the bottom of the vessel, so that a relatively wide annular space 30 for the melt results in front of the first seal 20.
- This relatively large mass of the melt surrounding the bore 7 reduces its cooling and counteracts blockage.
- the design of the stopper head 24, together with the horizontal arrangement of the throttle opening, also favors an approximately horizontal flow of the flowing melt, as indicated by arrows A in FIG. 3. This prevents eddy formation in the melt even when the melt is low in the vessel, so that slag is not prematurely drawn into the pouring spout.
- this annulus 30 or the like by argon. be rinsed, which can be supplied via thin feed lines 33 in the plug 6. This feed line 33 can also be used to generate a control signal. As soon as the outlet end emerges from the melt, there is a pressure drop in the gas of the feed line. This allows the casting process to be interrupted before slag is carried along.
- the second seal (21) can also be kept free of penetrating melt by blowing gas through bores (34).
- two throttle openings 14 ′′ are arranged on opposite sides of the pin 13 and are offset from one another with respect to the central axis, so that they run approximately tangentially to the longitudinal outlet opening 15. This creates a swirl in the flowing out melt according to the arrows, which prevents deposits on the walls of the spout, since the lighter inclusions remain in the center of the vortex.
- the vessel 1 is designed as an intermediate container with a pouring distributor 30 and a plurality of pouring plugs 6 which can be rotated independently of one another.
- a problem with such distribution vessels or intermediate containers with several pouring openings is that that the melt temperature is different due to different lengths of passageways, which is undesirable.
- By immersing the pouring distributor 30 in the melt and the directed and rotatable, predominantly horizontal pouring opening 32 below the bath level an approximately horizontal outlet of the melt and a calmed flow pattern approximately in the sense of the flow paths T in FIGS. 7, 8 and 9 result The course of the flow depends on the inflow angle ⁇ of the pouring distributor 30 and on the outflow angles ⁇ of the plugs 6.
- the flow vectors of the pouring and the pouring spouts generate a torque in the melt, as a result of which the individual melting elements sink from the hot surface layer near the surface to the colder layer near the ground. Due to the helical flow pattern, a passage path of the same length is sought for all throttle openings 14 in order to avoid temperature differences.
- the flow paths T shown schematically in FIGS. 7, 8 and 9 will not be strictly observable in practice, but due to the mixing of the melt with partial flows, there is a good temperature distribution and the avoidance of dead zones. 7 and 8, only one half of such an intermediate container is shown.
- the residence time of the melt in the vessel 1 can be influenced by a suitable choice of the angles ⁇ and ⁇ . Due to the calming flow, non-metallic inclusions have the opportunity to quickly rise to the surface in the floating slag layer through their own buoyancy, so that they are not dragged into the outlet channel by turbulence. This also applies to slags. Due to the forced, essentially horizontal flow in the pouring area of the metallurgical vessel 1, eddies and thus a premature slag run are avoided. This improves the quality of the end product, reduces scrap and increases production.
- FIG. 9 shows the cross section through the intermediate container, from which it can be seen that the walls are strongly inclined, as a result of which a preferred flow path is forced.
- the individual plugs 6 according to FIGS. 7-9 correspond to those according to FIG. 1 and can thus be raised, lowered and rotated, as was explained in connection with FIG. 1.
- the control can be carried out individually or together using a predetermined program, depending on casting parameters such as temperature, throughput, analysis. Data processing systems can also be used for this.
- the sprue distributor 30 can also be included in such a program control, i.e. the angle ⁇ and / or its altitude can be changed.
- the throttle cross sections of the plugs 6 can also be individually regulated by raising or lowering them.
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- Engineering & Computer Science (AREA)
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- Furnace Charging Or Discharging (AREA)
- Carbon Steel Or Casting Steel Manufacturing (AREA)
- Casting Support Devices, Ladles, And Melt Control Thereby (AREA)
Abstract
Description
Die Erfindung bezieht sich auf eine Auslass- und Durchflussregel-Vorrichtung für ein metallurgische Schmelzen aufnehmendes Gefäss, das ein am Gefässboden befindliches Auslassrohr mit einer Ausgussöffnung aufweist, mit einem mit dem Auslassrohr zusammenwirkenden Stopfen, wobei der Stopfen in seiner geschlossenen Stellung einen in die Bohrung des Auslassrohres hineinragenden, mindestens angenähert zylindrischen, als Absperrorgan dienenden Zapfen, der an seinem Umfang mindestens eine radiale Drosselöffnung enthält, die in einen unten offenen Längskanal des Zapfens übergeht und zwischen Stopfen und Auslassrohr oberhalb der Drosselöffnung eine durch Absenken des Stopfens schliessbare erste Dichtung vorhanden ist.The invention relates to an outlet and flow control device for a metallurgical melt-receiving vessel, which has an outlet pipe located on the bottom of the vessel with a pouring opening, with a stopper which cooperates with the outlet pipe, the stopper in its closed position inserting one into the bore of the Exhaust pipe protruding, at least approximately cylindrical, serving as shut-off device, which contains at least one radial throttle opening on its circumference, which merges into a longitudinal channel of the pin open at the bottom and between the plug and the outlet pipe above the throttle opening there is a first seal that can be closed by lowering the plug.
Ferner bezieht sich die Erfindung auf ein Giessverfahren zum Abgiessen von Metallschmelze aus einem metallurgischen Gefäss, das mindestens eine am Gefässboden befindliche Auslassöffnung enthält, die mit einem Stopfen unter Bildung von Dichtungsorganen zusammenwirkt, wobei die Schmelze in der geöffneten Stopfenposition über eine mindestens angenähert horizontale Auslassöffnung im Stopfen und dessen unten offenen Längskanal ausfliesst.Furthermore, the invention relates to a casting method for pouring molten metal from a metallurgical vessel, which contains at least one outlet opening located on the bottom of the vessel, which cooperates with a stopper to form sealing elements, the melt in the opened stopper position via an at least approximately horizontal outlet opening in the Plug and its longitudinal channel open at the bottom flows out.
Für den Auslass und die Durchflussregelung von metallischen Schmelzen aus einem Gefäss sind bereits zahlreiche Vorrichtungen bekannt.Numerous devices are already known for the outlet and the flow control of metallic melts from a vessel.
Bei einem altbekannten System zum Vergiessen von Rohstahl od.dgl. wird eine Stopfenvorrichtung verwendet, bei der die im Gefässboden befindliche Auslassöffnung durch einen im Gefässinnern befindlichen Stopfen verschliessbar ist, der am untern Ende einer Stange befestigt ist. Durch ein von aussen betätigbares Hebelgestänge kann der Stopfen zum Giessen angehoben und zum Verschliessen des Ausgusses abgesenkt werden. Nachteilig sind indessen die schlechte Regelcharakteristik des Durchflusses und eine unbefriedigende Verschliess-Sicherheit, beispielsweise bei Bildung von Ansätzen am Stopfen.In a well-known system for casting crude steel or the like. a stopper device is used in which the outlet opening in the bottom of the vessel can be closed by a stopper in the inside of the vessel, which is fastened to the lower end of a rod. The plug can be raised for casting and lowered for closing the spout by means of a lever linkage that can be operated from the outside. Disadvantages are, however, the poor control characteristics of the flow and an unsatisfactory security against closure, for example if there are lugs on the stopper.
Es ist ferner schon vorgeschlagen worden, kalottenartige Drehventile zu verwenden, bei denen ein aussermittiger Einlasskanal durch eine Drehverbindung mit einer Auslassöffnung in kommunizierende Verbindung gebracht werden kann. Dies bedingt hohe Bearbeitungs- und Einschleifgenauigkeit der schwierig herzustellenden spährischen Trennstelle zwischen drehbaren und ruhenden Bauteilen. Ausserdem neigt die Schmelze bei einer solchen Konstruktion in der Eingussöffnung zum Einfrieren.It has also been proposed to use dome-type rotary valves in which an eccentric inlet channel can be brought into communicating connection with an outlet opening by means of a rotary connection. This requires high processing and grinding accuracy of the difficult to manufacture spherical separation point between rotating and stationary components. In addition, with such a construction, the melt tends to freeze in the pouring opening.
Es sind ferner unten an das die Schmelze enthaltende Gefäss angebaute Schieberverschlüsse bekannt. Bei solchen Schieberverschlüssen sind die unter Vorspannung aufeinander gleitenden Verschlusskörper einer erheblichen Abnützung ausgesetzt, da die Bewegung des verstellbaren Teiles unter Einwirkung der hohen Temperatur der Metallschmelze erfolgen muss. Nachteilig sind ferner die hohen Anschaffungs- und Unterhaltskosten. Um eine ausreichende Sicherheit der Dichtung zu gewährleisten, wird eine hohe Bearbeitungsgenauigkeit der aus feuerfestem Material bestehenden Schieberplatten verlangt.Slider closures are also known attached to the vessel containing the melt. In such slide closures, the closure bodies sliding on one another under pretension are subject to considerable wear, since the movement of the adjustable part must take place under the influence of the high temperature of the molten metal. Another disadvantage is the high purchase and Maintenance costs. In order to ensure sufficient security of the seal, high machining accuracy of the slide plates made of refractory material is required.
Aus der FR-A 2 315 347 ist eine Vorrichtung zur Auslassregelung von Schmelzen bekannt, bei der ein durch ein Gestänge von unten betätigbarer Stopfen vorhanden ist. Der Stopfen-Kopf ist mit einer Dichtfläche versehen, die zusammen mit einem ringförmigen Lochstein eine Dichtung bildet. Der Stopfen ist direkt anschliessend an die Dichtfläche mit mehreren radialen Oeffnungen versehen, die in einen mittigen, unten offenen Auslasskanal einmünden. Unbefriedigend ist die bruchgefährdete Schwächung des Stopfenquerschnittes direkt unterhalb des Kopfes, da die zur Verwendung gelangenden feuerfesten Materialien zwar eine hohe Druckfestigkeit aber nur eine geringe Zugfestigkeit haben und hier zur Erzeugung des Schliesskraft eine Zugbeanspruchung auftritt. Auch die Verschliess-Sicherheit ist unbefriedigend wegen der Gefahr der Bildung von Ansätzen oder Erosion im Verschlussbereich. Bei Versagen der Dichtung hat ein Durchbruch der Schmelze katastrophale Folgen. Die Gefahr des Schlackenmitlaufes kann mit dieser Verschluss-Vorrichtung nicht behoben werden, da sich zusammen mit der muldenförmigen Vertiefung im Lochstein eine schräge oder sogar im wesentlichen vertikale Strömung in der Schmelze ausbildet. Weiter besteht Einfriergefahr beim Angiessen, da sich die Schmelze in der im Querschnitt keilförmigen Mulde rasch abkühlt. Da die Fuge zwischen dem beweglichen Stopfen und dem stationären Lochstein unten mit Umgebungsluft in Verbindung steht, kann durch das beim Giessen entstehende Vakuum Luft angesaugt werden, wodurch eine unerwünschte Reoxydation der Schmelze entsteht.From FR-A 2 315 347 a device for regulating the outlet of melts is known, in which there is a stopper which can be actuated by a linkage from below. The plug head is provided with a sealing surface, which forms a seal together with an annular perforated brick. The stopper is provided directly adjacent to the sealing surface with a plurality of radial openings which open into a central outlet channel which is open at the bottom. The weakening of the plug cross-section directly below the head, which is at risk of breakage, is unsatisfactory, since the refractory materials used have a high compressive strength but only a low tensile strength and tensile stress occurs here to generate the closing force. The security of the closure is also unsatisfactory because of the risk of build-up or erosion in the closure area. If the seal fails, a melt breakthrough has catastrophic consequences. The risk of slag entrainment cannot be eliminated with this closure device, since, together with the trough-shaped depression in the perforated brick, an oblique or even essentially vertical flow forms in the melt. There is also a risk of freezing when pouring on, since the melt cools rapidly in the trough which is wedge-shaped in cross section. Since the joint between the movable plug and the stationary perforated brick is connected to ambient air at the bottom, air can be sucked in by the vacuum created during casting, which causes undesired reoxidation of the melt.
Die DE-A 1 558 285 zeigt einen Hubkolbenverschluss für Giesspfannen. Der Hubkolben ist mit unten angreifenden Antriebsmitteln versehen, mit denen eine reine Axialverschiebung in die Oeffnungs- und Schliess-Stellung bewirkt werden kann. Eine radiale Oeffnung mündet in eine mittige, unten offene Durchflussöffnung. Da am Hubkolben ein verbreiterter Kopf fehlt, ist die Dichtung auf den oberhalb der radialen Oeffnung des Hubkolbens befindlichen Teil zusammen mit der Lochsteinbohrung beschränkt. Der Lochstein sitzt in einer trichterförmig vertieften Oeffnung des Pfannenbodens, weshalb sich beim Giessen keine überwiegend horizontale Strömungsrichtung ausbildet, sondern der Sog der ausfliessenden Schmelze wird sich in Aufwärtsrichtung fortpflanzen und als Folge davon können Schlackenteile mitgerissen werden.DE-A 1 558 285 shows a piston lock for ladles. The reciprocating piston is provided with drive means which engage at the bottom and with which a pure axial displacement into the opening and closing position can be effected. A radial opening opens into a central flow opening that is open at the bottom. Since a widened head is missing on the reciprocating piston, the seal is limited to the part located above the radial opening of the reciprocating piston together with the perforated brick hole. The perforated stone sits in a funnel-shaped recess in the bottom of the pan, which is why no predominantly horizontal direction of flow is formed during pouring, but the suction of the flowing melt will propagate in the upward direction and, as a result, parts of the slag can be entrained.
Die mit der Erfindung zu lösende Aufgabe besteht in der Schaffung einer Auslass- und Durchflussregelvorrichtung und eines Giessverfahrens, die einen einfachen, kostengünstig herstellbaren Aufbau hat, ein stetiges, genaues Regeln des Durchflusses von Schmelze erlaubt, und eine hohe Dichtsicherheit ergibt und beim Giessverfahren eine Wirbelbildung weitgehend vermieden und ein Schlackenmitlauf der abfliessenden Schmelze verhindert werden, unter Beibehaltung einer guten Durchflussregelbarkeit und Dichtsicherheit.The object to be achieved with the invention is to create an outlet and flow control device and a casting method which has a simple, inexpensive to manufacture structure, allows a constant, precise control of the flow of melt, and results in a high level of sealing reliability and at The casting process largely avoids the formation of eddies and prevents slag running along the outflowing melt, while maintaining good flow controllability and tightness.
Die erfindungsgemässe Vorrichtung mit der diese Aufgabe gelöst wird ist dadurch gekennzeichnet, dass sich der Stopfen am unteren Ende einer von oben her in das Innere des Gefässes hineinragenden, höhenbeweglichen Stange befindet, die Stange gelenkig gelagert ist und gegenüber dem sie umgebenden Stopfenhals radiales Spiel hat, und der Zapfen zwischen seiner radialen Drosselöffnung und der sich darüber befindlichen Dichtfläsche einen am Mantel geschlossenen Ringteil enthält, der zusammen mit dem benachbarten Teil der Bohrung eine zweite Dichtung bildet.The device according to the invention with which this object is achieved is characterized in that the stopper is located at the lower end of a vertically movable rod protruding from above into the interior of the vessel, the rod is articulated and has radial play with respect to the stopper neck surrounding it, and the pin between its radial throttle opening and the sealing surface located above it contains a ring part closed on the casing, which together with the adjacent part of the bore forms a second seal.
Das erfindungsgemässe Giessverfahren ist dadurch gekennzeichnet, dass der Schmelze im stopfennahen Bereich eine überwiegend horizontale Strömungsrichtung gegeben wird, und dass durch Veränderung der Drehwinkellage der mindestens angenähert horizontalen Auslassöffnung des Stopfens die Einströmrichtung in den Stopfen während des Abfliessens aus dem Gefäss kontinuierlich verändert wird.The casting method according to the invention is characterized in that the melt is given a predominantly horizontal flow direction in the area near the stopper, and that by changing the angle of rotation of the at least approximately horizontal outlet opening of the stopper, the inflow direction into the stopper is continuously changed during the outflow from the vessel.
Durch die Betätigung des Stopfens mittels einer von oben in das Schmelzgefäss hineinragende Stange, lässt sich der Betätigungsmechanismus extrem einfach ausbilden. Es entfallen alle beweglichen Einbauten unterhalb des Schmelzgefässbodens, die infolge ihres Platzbedarfes störend sind und die in ihrer Bewegungsfunktion unter Hitzeeinwirkung und durch Metallspritzer gefährdet sind. Da der Stopfen in Schliessrichtung auf Druck beansprucht ist, ergibt sich eine hohe Schliess-Sicherheit, im Unterschied zu einer Stopfenbetätigung von unten, bei der die Schliesskraft eine Zugbeanspruchung des Stopfens erfordert und die Feuerfestmaterialien - im Vergleich zu ihrer Druckfestigkeit - nur eine wesentlich geringere Zugfestigkeit haben.By actuating the stopper by means of a rod protruding into the melting vessel from above, the actuating mechanism can be designed extremely easily. There are no moving fixtures beneath the bottom of the melting vessel, which are annoying due to their space requirement and which are endangered in their movement function under the influence of heat and metal splashes. Since the stopper is subjected to pressure in the closing direction, there is a high degree of locking security, in contrast to a stopper actuation from below, in which the closing force requires the stopper to be subjected to tensile stress and the refractory materials - compared to their compressive strength - only have a significantly lower tensile strength to have.
Der Stopfen und die Bohrung im Ausgussrohr lassen sich mit konventionellen Herstellungsmethoden präzise herstellen. Zur Erreichung einer wirksamen Abdichtung muss der Stopfen praktisch spielfrei in die Bohrung des Ausgussrohres hineinpassen. Die zur Verwendung gelangenden hochhitzebeständigen Materialien haben in aller Regel zwar eine hohe Druckfestigkeit aber nur eine geringe Biegefestigkeit. Dies ergibt bei der Stopfen-Montage zusammen mit der relativ langen Stange Probleme, da bei einer mit dem Zapfen nicht genau fluchtenden Anordnung der Betätigungsstange Biegekräfte auftreten, die entweder ein Klemmen des Stopfen-Sitzes verursachen würden, oder sogar zum Abbrechen des Stopfens führen. Ausserdem ist zu beachten, dass ein Hitzeverzug sowohl bei der Stange als auch am Gefäss unter der Schmelzwärme auftreten kann, was beispielsweise zu einer leichten Krümmung der Stange und damit zu deren Biegebeanspruchung führen kann. Diese Probleme sind dadurch behoben, dass die Stange gelenkig gelagert ist und die Stange gegenüber dem sie umgebenden, in die Schmelze eintauchenden Stopfenhals radiales Spiel hat. Dadurch lassen sich sowohl Montageungenauigkeiten als auch ein Wärmeverzug ausgleichen, ohne dass der Stopfen auf Biegung belastet wird.The plug and the bore in the pouring spout can be precisely manufactured using conventional manufacturing methods. To achieve an effective seal, the plug must fit into the bore of the pouring spout with virtually no play. The high-heat-resistant materials used generally have a high compressive strength, but only a low flexural strength. This results in problems with the plug assembly together with the relatively long rod, since if the actuating rod is not exactly aligned with the pin, bending forces occur which would either cause the plug seat to jam or even lead to the plug being broken off. It should also be noted that heat distortion can occur both in the rod and on the vessel under the heat of fusion, which can lead to a slight curvature of the rod and thus to its bending stress, for example. These problems are remedied by the fact that the rod is articulated and the rod is opposite the surrounding one, plug neck immersed in the melt has radial play. This means that both inaccuracies in assembly and heat distortion can be compensated for without the plug being subjected to bending.
Eine erste Dichtung ergibt sich in an sich bekannter Weise, indem in der Schliessposition ein konischer Ansatz gegen den Bohrungsrand des Ausflussrohres anliegt. Die Durchbruchsicherheit für die Schmelze wird durch eine zweite, kumulativ wirkende Dichtungseinrichtung stark erhöht. Diese besteht darin, dass am Zapfen zwischen seiner Drosselöffnung und der sich darüber befindlichen konischen Dichtfläche ein am Mantel geschlossener Ringteil vorhanden ist, der zusammen mit der Bohrung die zweite Dichtung bildet. Dies ergibt eine verbesserte Sicherheit gegen Leckage, da die beiden Dichtungen nacheinander und erst nach Zurücklegung einer der Ringbreite V entsprechenden Hubbewegung des Stopfens wirksam werden. Dadurch bleibt selbst eine Erosion an der Drosselöffnung des Stopfens ohne nachteilige Folgen für die sichere Abdichtung der Auslassöffnung, sodass sich kostspielige Notschieber vermeiden lassen. Solche Stopfen-Vorrichtungen mit sicherer Dichtfunktion haben eine längere Einsatzdauer, wodurch die Betriebskosten gesenkt werden können.A first seal is obtained in a manner known per se, in that, in the closed position, a conical shoulder rests against the edge of the bore of the outflow pipe. The breakthrough security for the melt is greatly increased by a second, cumulative sealing device. This consists in that a ring part which is closed on the jacket and which forms the second seal together with the bore is present on the pin between its throttle opening and the conical sealing surface located above it. This results in improved security against leakage, since the two seals take effect one after the other and only after a stroke movement of the stopper corresponding to the ring width V has been covered. As a result, even erosion remains at the throttle opening of the stopper without adverse consequences for the reliable sealing of the outlet opening, so that expensive emergency shutters can be avoided. Such stopper devices with a reliable sealing function have a longer service life, as a result of which the operating costs can be reduced.
Eine gute Regelcharakteristik für den Durchfluss der Schmelze ergibt sich dadurch, dass die auslaufende Menge der Metallschmelze pro Zeiteinheit durch den Hub des Stopfens direkt einstellbar und dosierbar ist, wodurch besonders das Angiessen erleichtert wird. Auf diese Weise kann zum Angiessen auf die konventionelle Sandfüllung verzichtet werden, die eine unerwünschte Beimischung ergibt.A good control characteristic for the flow of the melt results from the fact that the amount of molten metal flowing out per unit of time can be adjusted and metered directly by the stroke of the stopper, which in particular makes casting on easier. In this way, conventional sand filling, which results in an undesired admixture, can be dispensed with.
Beim Vergiessen metallurgischer Schmelzen besteht das altbekannte Problem, ein Mitlaufen von Schlacke und nicht metallischen Einschüssen möglichst zu verhindern.When casting metallurgical melts, there is the well-known problem of preventing slag and non-metallic bullets from running along.
Beim erfindungsgemässen Giessverfahren bewirkt die weitgehend horizontale Strömungsrichtung eine Beruhigung der Schmelze, welche das Ausscheiden nichtmetallischer, langsam an die Oberfläche steigender Einschlüsse begünstigt. Zudem wird beim Giessen die gefässbodennahe Schmelzschicht abgeführt. Dies verhindert einen vorzeitigen Schlackenmitlauf oberhalb eines minimalen Badstandes. Die weitgehend horizontale Strömungsrichtung wird durch die radiale Anordnung der einzigen Drosselöffnung im Stopfen zusammen mit der Drehmöglichkeit begünstigt. Da die horizontale Ausgussöffnung während des Abgiessvorganges verdreht werden kann, lassen sich die Strömungsverhältnisse der jeweiligen Gefässform, der unter schiedlichen Badhöhe, der Schmelzentemperatur sowie weitem Parametern von Fall zu Fall anpassen. Als Folge der beruhigten Einguss-Strömung durch den Eingussverteiler entstehen keine Rückprallwellen der Schmelze vom Boden, wodurch das Aufspülen der die Reoxidation verhindernden schwimmenden Schlackenschicht vermieden wird. Die beruhigte Strömung erleichtert und beschleunigt zudem das Aufsteigen nichtmetallischer Einschlüsse an die Oberfläche der Schmelze.In the casting method according to the invention, the largely horizontal direction of flow calms the melt, which favors the elimination of non-metallic inclusions that slowly rise to the surface. In addition, the melt layer near the bottom of the vessel is removed during casting. This prevents premature slag running above a minimum bath level. The largely horizontal flow direction is favored by the radial arrangement of the single throttle opening in the stopper together with the possibility of rotation. Since the horizontal pouring spout can be rotated during the pouring process, the flow conditions of the respective vessel shape, the different bath height, the melt temperature and other parameters can be adjusted from case to case. As a result of the calmed down pouring flow through the pouring distributor, there are no rebounding waves of the melt from the floor, which prevents the floating of the floating slag layer that prevents reoxidation. The calm flow eased and also accelerates the rise of non-metallic inclusions to the surface of the melt.
In der Zeichnung sind Ausführungsbeispiele der Erfindung dargestellt. Es zeigen:
- Fig. 1 einen Schnitt durch die Vorrichtung samt Schmelzgefäss
- Fig. 2 einen Teilschnitt durch den Stopfen in seiner in die Ausgussöffnung hineinragenden, geschlossenen Stellung
- Fig. 3 einen Schnitt durch den Stopfen in seiner offenen Stellung
- Fig. 4 einen Querschnitt durch eine Ausführungsvariante in Richtung der pfeile IV-IV in Fig. 5
- Fig. 5 einen Längsschnitt durch die Ausführungsvariante gemäss Fig. 4 mit einer Vielzahl von Drosselöffnungen
- Fig. 6 einen Querschnitt durch eine weitere Ausführungsvariante mit zueinander versetzten Drosselöffnungen zur Erzeugung eines Dralles für die ausfliessende Schmelze
- Fig. 7 einen Längsschnitt durch ein als Zwischenbehälter ausgebildetes Gefäss, mit Eingussverteiler und mehreren Stopfen
- Fig. 8 eine Draufsicht auf den Zwischenbehälter gemäss Fig. 7 mit Darstellung unterschiedlicher Drehlagen der Ausgussöffnungen der Stopfen im Schnitt
- Fig. 9 einen Querschnitt durch den Zwischenbehälter gemäss Fig. 7 mit starker Querschnittsverjüngung nach unten.
- Fig. 1 shows a section through the device including the melting vessel
- Fig. 2 is a partial section through the stopper in its protruding into the pouring opening, closed position
- Fig. 3 shows a section through the stopper in its open position
- 4 shows a cross section through an embodiment variant in the direction of the arrows IV-IV in FIG. 5
- 5 shows a longitudinal section through the embodiment variant according to FIG. 4 with a large number of throttle openings
- Fig. 6 shows a cross section through a further embodiment with staggered throttle openings for generating a swirl for the outflowing melt
- 7 shows a longitudinal section through a vessel designed as an intermediate container, with a pouring distributor and several plugs
- Fig. 8 is a plan view of the intermediate container of FIG. 7, showing different rotational positions of the pouring openings of the plugs in section
- FIG. 9 shows a cross section through the intermediate container according to FIG. 7 with a strong cross-sectional taper downwards.
Gemäss Fig. 1 befindet sich im Boden 2 eines Gefässes 1 zur Aufnahme einer Metallschmelze eine Auslassöffnung mit einem unten offenen Auslassrohr 3. In die Bohrung 7 dieses Auslassrohres 3 ragt ein Stopfen 6 aus feuerfestem Material hinein, mit dem der Durchfluss der Schmelze reguliert, verschlossen oder geöffnet werden kann.1, in the
In den Stopfenhals 10 ragt eine Stopfenstange 5 hinein, mit welcher der Stopfen 6 in Vertikalrichtung bewegt und um seine Achse verdreht werden kann. Der Antrieb erfolgt durch eine ausserhalb des Gefässes 1 befindliche Antriebseinrichtung 17. Der vertikale Antrieb kann aus einer mechanischen, motorisch angetriebenen Spindel 8 oder einem hydraulischen oder pneumatischen Hubzylinder bestehen. Mit dem vertikalen Führungsorgan 9 ist oberhalb des Gefässrandes ein horizontaler Arm 23 verbunden. Die Verbindung des Armes 23 mit dem obern Ende der Stopfenstange 5 und unten mit dem glockenartigen Stopfenkopf 24 erfolgt je durch eine Kupplungskugel 11. Die im Stopfenhals 10 gehaltene Stopfenstange 5 hat radiales Spiel. Die zur Verdrehung des Stopfens 6 um seine Vertikalachse vorgesehene Drehantriebsvorrichtung 17 steht mit einem nicht näher dargestellten Antriebsmotor in Verbindung. Dieser Motor kann ein Servo- oder Schrittschaltmotor sein, mit dem sich unterschiedliche Drehlagen des Stopfens 6 progammieren und reproduzieren lassen. Die Veränderung der Drehlage des Stopfens 6 könnte auch durch pneumatische oder hydraulische Drehantriebe erfolgen.A
Der Stopfen 6 enthält einen in eine Bohrung 7 des Auslasskanales 4 eingreifenden zylindrischen Zapfen 13. Dieser Zapfen 13 ist mit einer horizontalen radialen Drosselöffnung 14 versehen, die in einen axialen unten offenen Bohrungsteil 12 einmündet und in den Ausgusskanal 4 übergeht. Da der Zapfen 13 radial nur auf einer Seite offen ist, wird der abfliessenden Metallschmelze eine vorbestimmte Strömungsrichtung aufgezwungen, die in Fig. 1 mit der Linie S angedeutet ist. Dabei wird im Bereich vor der Ausgussöffnung zusammen mit dem gegenüber dem Zapfen 13 durchmessergrösseren glockenartigen Stopfenkopf 24 eine möglichst horizontale Strömung angestrebt um eine Wirbelbildung der Schmelze und damit eine Schlackenansaugung von oben zu verhindern. Durch Drehung des Stopfens 6 um seine Vertikalachse kann dabei die Strömungsrichtung auch während des Giessvorganges schrittweise oder kontinuierlich beeinflusst werden. Durch Absenken des Stopfens 6 wird der Durchfluss-Querschnitt der Drosselöffnung vermindert oder ganz geschlossen.The
Die Fixierung des Stopfengestänges 23 mit der obern Kupplungskugel 11 der Stopfenstange 5 kann automatisch mit einer Klemmvorrichtung erfolgen. Dadurch muss die mit Spiel bewegliche Stopfenstange 5 und der in ihrem unteren Ende befindliche Stopfen 6 vor der Montage nicht genau ausgerichtet werden. Ein die Stopfenstange 5 umgebender Stopfenhals 10 dient als Schutz vor der Schmelze. Da die Regelkräfte direkt über das Stopfengestänge 23 in den Kopf des Stopfens 6 geleitet werden, ist der Stopfen 6 von Biegekräften durch Ausrichtfehler geschützt. Die sonst üblichen Ausrichtarbeiten für den Stopfen 6 entfallen und der Stopfen kann auch bei heissen metallurgischen Gefässen automatisch eingesetzt werden, was eine Verminderung der Gefässumlaufzeiten ergibt und somit Unterhaltskosten eingespart werden.The
Nachfolgend wird die Ausbildung einer Ausführungsvariante des Stopfens 6 in der geschlossenen und in der geöffneten Stellung an Hand der Fig. 2 und 3 näher beschrieben. Der Stopfen 6 enthält einen in die Bohrung 7 des Ausgussrohres 3 hineinragenden zylindrischen oder leicht konischen Zapfen 13. In diesem Zapfen 13 befinden sich - in Abweichung zur Ausführungsform nach Fig. 1 - mehrere radiale Drosselöffnungen 14. Diese sind am Zapfenumfang gleichmässig verteilt. Der obere und der untere Bereich dieser Drosselöffnungen 14 ist je keilförmig ausgeführt, während der mittlere Bereich dieser Drosselöffnungen 14 parallele vertikale Seitenwände 18 enthält. Die Längsachsen der Drosselöffnungen 14 erstrecken sich in Vertikalrichtung, also in Richtung der Stopfenbewegung. Dadurch lässt sich eine gegenüber runden Drosselöffnungen vorteilhaftere Regelcharakteristik erreichen. Die Drosselöffnungen 14 münden in den zentralen unten offenen Längsbohrungsteil 15 des Zapfens 13 ein. Oberhalb den Drosselöffnungen 14 geht der Zapfen 13 in eine kegelstumpfförmige Verbreiterung 16 über, welche eine kegelstumpfförmige Absperrfläche bildet. Der Zentriwinkel dieser Absperrfläche bildet einen Winkel von 75° bis 105°, vorzugsweise 90°. Zusammen mit einer kegelstumpfförmigen Ansenkung 18 am obern Rand der Bohrung 7 mit gleichem Winkel ergibt dies eine ringförmige erste Dichtung 20. Zwischen den obersten Kanten der Drosselöffnungen 14 und der kegelstumpfförmigen Absperrfläche 16 befindet sich am Zapfen 13 ein geschlossener, zylindrischer Ringteil 19 mit der Breite V (Fig. 3). Bei geschlossenem, also abgesenktem Stopfen 6 ergibt dieser Ringteil 19 zusammen mit der benachbarten im Durchmesser passenden zylindrischen Bohrung 7 eine zweite Dichtung 21. Der unterste Teil des Zapfens 13 ist ebenfalls als ein am Mantel geschlossener Ringteil 22 ausgeführt, sodass der Zapfen 13 in der Bohrung 7 geführt bleibt, auch wenn die Drosselöffnungen 14 voll geöffnet sind.The design of an embodiment variant of the
Da in der geschlossenen Stellung des Stopfens 6 gemäss Fig. 2 die Drosselöffnungen 14 mit der Schmelze nicht in Berührung sind, besteht keine Gefahr, dass die Schmelze in diesem Bereich einfrieren kann. Oberhalb der kegelstumpfförmigen Verbreiterung 16 ist der Stopfenkopf 24 glockenförmig erweitert. Die etwa horizontale Unterkante 26 des verbreiterten Stopfenkopfes 24 hat bei geschlossenem Stopfen 6 einen relativ grossen Abstand von der über den Gefässboden vorstehenden Horizontalfläche 28 des Ausgussrohres 3, sodass sich vor der ersten Dichtung 20 ein relativ breiter Ringraum 30 für die Schmelze ergibt. Durch diese die Bohrung 7 umgebende, relativ grosse Masse der Schmelze wird deren Abkühlung vermindert und einer Verstopfung entgegengewirkt. Die Ausbildung des Stopfenkopfes 24 begünstigt zudem zusammen mit der horizontalen Anordnung der Drosselöffnung eine angenähert horizontale Strömung der zufliessenden Schmelze, wie dies in Fig. 3 durch Pfeile A angedeutet ist. Dies verhindert eine Wirbelbildung in der Schmelze auch bei niedriger Höhe der Schmelze im Gefäss, sodass Schlacke nicht vorzeitig in den Ausguss eingezogen wird. Zudem kann dieser Ringraum 30 durch Argon od.dgl. gespült werden, welches über dünnen Zuleitungen 33 im Stopfen 6 zugeführt werden kann. Diese Zuleitung 33 kann auch zur Erzeugung eines Steuersignales verwendet werden. Sobald das Austrittsende aus der Schmelze austritt, entsteht ein Druckabfall im Gas der Zuleitung. Dadurch lässt sich der Giessvorgang unterbrechen bevor Schlacke mitgeführt wird.Since the
Da zwei nacheinander zur Wirkung gelangende Dichtungen vorhanden sind, ergibt sich eine erhöhte Sicherheit gegen Durchbrüche der Schmelze, selbst wenn die Fläche 16 oder die Ansenkung 18 der ersten Dichtung 20 durch Verschleiss beschädigt sein sollte.Since there are two seals that come into effect one after the other, there is increased security against breakthroughs of the melt, even if the
Die zweite Dichtung (21) kann weiters durch Einblasen von Gas durch Bohrungen (34) von eindringender Schmelze freigehalten werden.The second seal (21) can also be kept free of penetrating melt by blowing gas through bores (34).
In den Fig. 4 und 5 ist eine Ausführungsvariante dargestellt, bei welcher die Drosselöffnungen im Stopfen 6 aus einer Vielzahl relativ kleiner radialer Löcher 14' am Umfang gebildet sind, die in axialen Reihen übereinander angeordnet sind. Dadurch wird eine Filterung der Schmelze bewirkt. Wenn sich die oberen Löcher 14' oder Lochreihen verschliessen, wird der Stopfen 6 weiter angehoben, so dass neue, noch offene Löcher für den Durchfluss und die Filterung frei gegeben werden.4 and 5, an embodiment variant is shown in which the throttle openings in the
Bei der Ausführungsvariante gemäss Fig. 6 sind zwei Drosselöffnungen 14'' auf gegenüberliegenden Seiten des Zapfens 13 angeordnet und bezüglich der Mittelachse zueinander versetzt, so dass sie zur Ausfluss-Längsöffnung 15 etwa tangential verlaufen. Dadurch entsteht bei der ausfliessenden Schmelze ein Drall gemäss den eingezeichneten Pfeilen, der Ablagerungen an den Wänden des Ausgusses verhindert, da die leichteren Einschlüsse in der Wirbelmitte verbleiben.In the embodiment variant according to FIG. 6, two
In den Fig. 7, 8 und 9 ist eine Ausführungsvariante dargestellt, bei der das Gefäss 1 als Zwischenbehälter ausgebildet ist mit einem Eingussverteiler 30 und mehreren unabhängig voneinander verdrehbaren Ausguss-Stopfen 6. Bei derartigen Verteilgefässen oder Zwischenbehälter mit mehreren Ausgussöffnungen besteht ein Problem darin, dass die Schmelzentemperatur, bedingt durch verschieden lange Durchlaufwege unterschiedlich wird, was unerwünscht ist. Durch das Eintauchen des Eingussverteilers 30 in die Schmelze und die gerichtete und drehbare, vorwiegend horizontale Eingussöffnung 32 unterhalb des Badstandes entsteht ein angenähert horizontaler Austritt der Schmelze und ein beruhigter Strömungsverlauf etwa im Sinne der Strömungspfade T in den Fig. 7, 8 und 9. Der Strömungsverlauf ist abhängig vom Einströmwinkel β des Eingussverteilers 30 und von den Ausströmwinkeln α der Stopfen 6. Die Strömungsvektoren des Eingusses und der Ausgüsse erzeugen ein Drehmoment in der Schmelze, wodurch die einzelnen Schmelzelemente von der oberflächennahen, heissen Schicht wendelförmig zu der bodennahen kälteren Schicht absinken. Durch den wendelförmigen Strömungsverlauf wird ein möglichst gleich langer Durchlaufweg für alle Drosselöffnungen 14 angestrebt, um Temperaturunterschiede zu vermeiden. Die in den Fig. 7, 8 und 9 schematisch eingezeichneten Strömungspfade T werden in der Praxis nicht rein einhaltbar sein, indessen ergibt sich infolge der Durchmischung der Schmelze mit Teilströmen eine gute Temperaturverteilung und die Vermeidung von toten Zonen. In den Fig. 7 und 8 ist nur die eine Hälfte eines solchen Zwischenbehälters dargestellt.7, 8 and 9 show an embodiment variant in which the vessel 1 is designed as an intermediate container with a pouring
Durch geeignete Wahl der Winkel α und β lässt sich die Verweilzeit der Schmelze im Gefäss 1 beeinflussen. Durch den beruhigenden Strömungsverlauf haben nichtmetallische Einschlüsse Gelegenheit durch eigenen Auftrieb schnell an die Oberfläche in die auf dieser schwimmende Schlackenschicht aufzusteigen, sodass sie nicht durch Turbulenz in den Auslasskanal mitgerissen werden. Dies trifft auch auf Schlacken zu. Durch die erzwungene, im wesentlichen horizontale Strömung im Ausgussbereich des metallurgischen Gefässes 1, werden Wirbel und somit ein vorzeitiger Schlackenmitlauf vermieden. Das verbessert die Qualität des Endproduktes, vermindert Ausschuss und erhöht die Produktion.The residence time of the melt in the vessel 1 can be influenced by a suitable choice of the angles α and β. Due to the calming flow, non-metallic inclusions have the opportunity to quickly rise to the surface in the floating slag layer through their own buoyancy, so that they are not dragged into the outlet channel by turbulence. This also applies to slags. Due to the forced, essentially horizontal flow in the pouring area of the metallurgical vessel 1, eddies and thus a premature slag run are avoided. This improves the quality of the end product, reduces scrap and increases production.
In Fig. 9 ist der Querschnitt durch den Zwischenbehälter dargestellt, aus welchem ersichtlich ist, dass die Wände stark geneigt sind, wodurch ein bevorzugter Strömungsweg erzwungen wird.9 shows the cross section through the intermediate container, from which it can be seen that the walls are strongly inclined, as a result of which a preferred flow path is forced.
Die einzelnen Stopfen 6 gemäss den Fig. 7-9 entsprechen denjenigen gemäss Fig. 1 und lassen sich somit heben, senken und drehen, wie dies im Zusammenhang mit Fig. 1 erläutert wurde. Die Steuerung kann durch ein vorbestimmtes Programm einzeln oder gemeinsam durchgeführt werden, in Abhängigkeit von Giessparametern wie Temperatur, Durchsatz, Analyse. Hiefür können auch Datenverarbeitungs-Anlagen eingesetzt werden. Auch der Eingussverteiler 30 kann in eine solche Programm-Steuerung einbezogen werden, d.h. der Winkel β und/oder seine Höhenlage kann verändert werden. Die Drosselquerschnitte der Stopfen 6 lassen sich zudem durch Anheben oder Absenken individuell regulieren.The individual plugs 6 according to FIGS. 7-9 correspond to those according to FIG. 1 and can thus be raised, lowered and rotated, as was explained in connection with FIG. 1. The control can be carried out individually or together using a predetermined program, depending on casting parameters such as temperature, throughput, analysis. Data processing systems can also be used for this. The
Claims (17)
- A discharge and flow control device for a vessel for molten metal, which comprises an outlet pipe (3) located on the vessel floor and having a discharge aperture, with a stopper cooperating with the outlet pipe, and in its closed position the stopper (6) comprises a journal (13) projecting into the bore (7) of the outlet pipe, which is at least roughly cylindrical and serves as a shut-off device, which on its periphery contains at least one radial throttle aperture (14) which extends into a longitudinal duct (15) of the journal (13) which is open at the bottom, and between stopper (6) and outlet pipe (3) above the throttle aperture (14) there is a first seal (16; 18) which can be closed by lowering the stopper (6), characterised in that the stopper (6) is located at the lower end of a height-adjustable rod (5) projecting from above into the interior of the vessel, the rod (5) is jointed and has radial clearance with respect to the stopper neck (10) surrounding it and, between its radial throttle aperture (14) and the sealing surface (16) above it, the journal (13) contains an annular part (19) closed on the shell, which forms a second seal (21) together with the adjacent part of the bore (7).
- A device according to Claim 1, characterised in that directly above the annular part (19) there is a closing surface (16) in the shape of a truncated cone and the upper edge of the bore (7) contains a countersinking (18) in the outlet pipe (3), which together with the closing surface (16) forms the first seal (20).
- A device according to Claim 1 or 2, characterised in that the journal (13) only contains a single throttle aperture (14), which is substantially horizontal and radially disposed.
- A device according to Claim 1 or 2, characterised in that the journal (13) contains several substantially horizontal radial throttle apertures (14) distributed over the periphery.
- A device according to Claim 1 or 2, characterised in that the throttle aperture(s) (14) is (are) constructed in a wedge-shape at least on the upper end and an adjacent oblong aperture region has parallel lateral surfaces (35).
- A device according to one of Claims 1-5, characterised in that above the closing surface (16) in the shape of a truncated cone the stopper (6) comprises a bell-shaped or mushroom-shaped stopper head (24).
- A device according to Claim 1, characterised in that the journal (13) has several rows of holes disposed above one another along its periphery, which are uncovered as the upward movement of the stopper (6) progresses.
- A device according to Claims 1, 2 or 6, characterised in that there are one or several throttle apertures (14) discharging tangentially into the longitudinal aperture (15).
- A device according to one of Claims 1-8, characterised in that in the uppermost part of the outlet pipe (3) there are bores (34) for blowing in gas.
- A device according to Claim 3, characterised in that there are adjustment means (17) for rotating the stopper (6).
- A device according to Claim 10, characterised in that the vessel (1) is an intermediate container, into which a pouring distributor (30) having a roughly horizontal pouring-in hole (32) projects, and in that the pouring distributor (30) is provided with a drive appliance (25) for height adjustment and/or a drive appliance (26) for rotation around its longitudinal axis.
- A device according to one of Claims 1-11, characterised in that at least one bore (33) for blowing in gas or powder discharges in the stopper (6) above the journal (13).
- A casting process for casting molten metal from a metallurgical vessel (1), which contains at least one outlet aperture located on the vessel floor, which cooperates with a stopper (6) by forming sealing organs, with the molten metal flowing out in the opened stopper position via at least one roughly horizontal outlet aperture (14) in the stopper (6) and its longitudinal duct (15) open at the bottom, characterised in that in the region near the stopper the molten metal is given a predominantly horizontal direction of flow and in that by changing the position of the angle of rotation (α) of the at least roughly horizontal outlet aperture (14) of the stopper (6) the direction of flowing in is continually changed during the flow from the vessel (1).
- A casting process according to Claim 13, characterised in that in addition the pouring flow of the molten metal into the vessel (1) is directed predominantly horizontally.
- A casting process according to Claim 14, characterised in that the pouring flow is continually changed with respect to the height and angle of rotation (β) relative to the vessel (1) during the casting operation.
- A casting process according to Claim 13, characterised in that the angle of rotation (α) of the outlet aperture (14) and/or the angle of rotation (β) of the pouring-in hole (32) is automatically changed as a function of at least one specified value or a specified programme.
- A casting process according to Claim 13, characterised in that there are several stoppers (6) which are adjusted with respect to the height and/or angle of rotation individually.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AT87907412T ATE57321T1 (en) | 1986-12-01 | 1987-11-27 | OUTLET AND FLOW CONTROL DEVICE FOR METALLURGICAL VESSELS AND CASTING PROCESSES. |
Applications Claiming Priority (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CH478186 | 1986-12-01 | ||
CH4781/86 | 1986-12-01 | ||
CH380587 | 1987-09-30 | ||
CH3805/87 | 1987-09-30 | ||
PCT/CH1987/000161 WO1988004209A1 (en) | 1986-12-01 | 1987-11-27 | Discharge and flow regulator for metallurgical vessels and casting process |
Publications (3)
Publication Number | Publication Date |
---|---|
EP0290523A1 EP0290523A1 (en) | 1988-11-17 |
EP0290523B1 EP0290523B1 (en) | 1990-10-10 |
EP0290523B2 true EP0290523B2 (en) | 1996-08-07 |
Family
ID=25693879
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP87907412A Expired - Lifetime EP0290523B2 (en) | 1986-12-01 | 1987-11-27 | Discharge and flow regulator for metallurgical vessels and casting process |
Country Status (6)
Country | Link |
---|---|
US (1) | US5004130A (en) |
EP (1) | EP0290523B2 (en) |
JP (1) | JPH01502168A (en) |
AU (1) | AU602179B2 (en) |
BR (1) | BR8707558A (en) |
WO (1) | WO1988004209A1 (en) |
Families Citing this family (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3809072A1 (en) * | 1988-03-18 | 1989-09-28 | Didier Werke Ag | TURN AND / OR SLIDE LOCK AND ITS LOCKING PARTS |
DE3934601C1 (en) * | 1989-10-17 | 1990-10-04 | Didier-Werke Ag, 6200 Wiesbaden, De | |
CH682376A5 (en) * | 1990-02-28 | 1993-09-15 | Stopinc Ag | A method for automatic casting of a continuous casting plant. |
DE4032084C1 (en) * | 1990-10-10 | 1992-05-27 | Didier-Werke Ag, 6200 Wiesbaden, De | |
DE4032083A1 (en) * | 1990-10-10 | 1992-04-16 | Didier Werke Ag | LOCKING AND / OR CONTROL DEVICE FOR POURING A METALLURGICAL VESSEL |
JPH0584460U (en) * | 1992-02-19 | 1993-11-16 | メイチュー精機株式会社 | Structure of molten metal pouring part |
DE4232006A1 (en) * | 1992-09-24 | 1994-03-31 | Leybold Ag | Device for opening and closing a bottom pouring opening in a vacuum induction melting and casting furnace |
US5544695A (en) * | 1993-06-01 | 1996-08-13 | Harasym; Michael | Antivortexing nozzle system for pouring molten metal |
CA2139889C (en) * | 1994-01-11 | 1999-04-06 | Charles W. Connors, Sr. | Tundish slag stopper with sealing rim |
US5560543A (en) * | 1994-09-19 | 1996-10-01 | Board Of Regents, The University Of Texas System | Heat-resistant broad-bandwidth liquid droplet generators |
US5820815A (en) * | 1996-01-17 | 1998-10-13 | Kennecott Holdings Corporation | Cooled tapping device |
WO1998016337A1 (en) * | 1996-10-12 | 1998-04-23 | Stopinc Ag | Driving device for a closing and/or regulating mechanism on the nozzle of a container containing a molten bath |
US8210402B2 (en) * | 2009-02-09 | 2012-07-03 | Ajf, Inc. | Slag control shape device with L-shape loading bracket |
JP2010236026A (en) * | 2009-03-31 | 2010-10-21 | Mitsubishi Materials Corp | Atomization apparatus |
SE534281C2 (en) * | 2009-12-08 | 2011-06-28 | Swerea Mefos Ab | Control device for a casting box |
Family Cites Families (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1558285A1 (en) * | 1921-05-15 | 1970-05-06 | Weinreich Dr Ing Wolfgang | Bottom closure for pouring pans |
US3083422A (en) * | 1959-04-13 | 1963-04-02 | Finkl & Sons Co | Porous stopper rod |
GB991513A (en) * | 1962-04-02 | 1965-05-12 | Earl Avery Thompson | Improvements in and relating to composite articles |
US3214804A (en) * | 1963-03-18 | 1965-11-02 | Allegheny Ludlum Steel | Ladles |
US3651825A (en) * | 1969-10-24 | 1972-03-28 | Francis P Sury | Stopper plug valve for hot metal ladles |
US3643680A (en) * | 1970-09-14 | 1972-02-22 | Kelsey Hayes Co | Bottom pour stopper |
IT1010787B (en) * | 1974-04-08 | 1977-01-20 | Salvagnini M | MOBILE DISCHARGER WITH SHUTTER FOR CHECKING THE FLOW OF MELTED METALS FROM THE RELATIVE CONTAINERS OPERATED WITH PNEUMATIC OR ELECTRONIC MECHANICAL SYSTEM |
FR2315347A1 (en) * | 1975-06-25 | 1977-01-21 | Salvagnini Mirella | Metal casting ladle stopper - is mushroom shaped with radial holes joining central bore |
DE3414252A1 (en) * | 1984-04-14 | 1985-10-17 | Betriebsforschungsinstitut VDEh - Institut für angewandte Forschung GmbH, 4000 Düsseldorf | Device for preventing the penetration of slag into the pouring stream of molten metal |
AU591889B2 (en) * | 1985-03-26 | 1989-12-21 | British Steel Plc | Improvements in or relating to outlet valves for metal containing vessels |
-
1987
- 1987-11-27 US US07/229,858 patent/US5004130A/en not_active Expired - Lifetime
- 1987-11-27 EP EP87907412A patent/EP0290523B2/en not_active Expired - Lifetime
- 1987-11-27 JP JP62506725A patent/JPH01502168A/en active Granted
- 1987-11-27 WO PCT/CH1987/000161 patent/WO1988004209A1/en active IP Right Grant
- 1987-11-27 BR BR8707558A patent/BR8707558A/en not_active IP Right Cessation
- 1987-11-27 AU AU82331/87A patent/AU602179B2/en not_active Ceased
Also Published As
Publication number | Publication date |
---|---|
US5004130A (en) | 1991-04-02 |
WO1988004209A1 (en) | 1988-06-16 |
AU8233187A (en) | 1988-06-30 |
EP0290523A1 (en) | 1988-11-17 |
AU602179B2 (en) | 1990-10-04 |
BR8707558A (en) | 1989-02-21 |
JPH0323263B2 (en) | 1991-03-28 |
JPH01502168A (en) | 1989-08-03 |
EP0290523B1 (en) | 1990-10-10 |
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