EP0025520B1 - Installation for measuring and conveying molten metal - Google Patents

Abstract

1. Installation for measuring and conveying molten metal, consisting of a gastight container (8) having an intake and offtake, with which smelt can be removed from a smelt container (1) or holding furnace or conversely from which smelt can be conveyed, for example, into a molten bath, characterised in that the intake (9) is at the same time the offtake (9) of the container (8) and the common intake/offtake (9) can be connected to a pipe system (5) which is present in the smelt container (1), in such a way that, by tilting or application of an excess pressure in the container (8), the smelt present in the container (8) is conveyed wholly or partially out of the container (8), and, upon the filling operation of the container (8), the smelt can no longer flow back into the molten bath of the smelt container (1).

Description

The invention relates to a device for metering and transporting metal melts, consisting of a gas-tight container with inlet and outlet, with which melt is removed from a melt container or holding furnace or vice versa, from which melt can be conveyed.

Various devices have become known, with which certain quantities of liquid metal can be dispensed using the principle of communicating vessels according to the principle of compressed gas production.

From US-PS 3058180 a device is known with which certain amounts of a melt can be poured off. For this purpose, a gas overpressure is generated in a storage vessel, so that the height of the liquid metal therein is lowered and a corresponding amount of the liquid is pressed out or poured out of an outflow pipe. To control the amount of gas required in the storage container, pyrometers are placed in the filling openings as probes.

In the previously known device, the tightness of the storage vessel is limited, since the device is constructed on the principle of communicating vessels and is therefore connected to the non-closable pouring or outlet openings.

In addition, accurate dosing is not possible because the discharge can only be interrupted by setting a pressure, and in particular if too much liquid metal has been poured out, it is no longer possible to automatically carry out a reflux or to suddenly stop the process.

GB-A-1 100475 has disclosed a device in which liquid metal is conveyed from a dense and heated storage vessel by means of gas pressure through an overflow pipe into an open vessel, from which the liquid metal is used either for the continuous supply of continuous casting equipment or intermittently Filled forms given off. Controlled dispensing is achieved by opening or closing a pouring opening on the bottom with a stopper. As a result, metered quantities of liquid metal can only be poured off with limited accuracy.

In DE-OS 2343100 a pressurized gas-operated dosing device for liquids, in particular liquid metals, aggressive acids and alkalis has become known, which consists of a sealed collecting container with an inlet pipe, the inlet pipe in the form of an angle lifter or an outlet on the side or bottom of a melting tank leads to a container serving as a metering device, which is provided with a weighing device, wherein different gas pressures for transporting the liquid from the melting container into the metering container and upon reaching the desired amount in the metering container to interrupt the flow can be set in the containers.

However, the metering device mentioned has the disadvantage that the metering container is firmly connected to the melting tank through the inlet pipe or the outlet, and that it is therefore not possible to transport the metering tank with the precisely determined amount of the melt contained therein.

The present invention is therefore based on the object of providing a device for metering of the type mentioned at the outset, which not only allows the metering process to be carried out by simple manipulations, but also with which precisely metered melt can be transported and transported to other locations, with filling and dosing operations can be carried out sequentially in a rational manner.

To achieve the object, a device for metering and transporting metal melts of the type mentioned at the outset, consisting of a gas-tight container with inlet and outlet, with which melt is removed from a melt container or holding furnace, or vice versa, from which melt is conveyed into a molten bath can be proposed, which is characterized in that the inlet is at the same time the outlet of the container and the common inlet / outlet can be connected to a pipe system located in the melting container, such that the container by tipping or applying an overpressure in the container All or part of the melt is conveyed out of the container and during the filling process of the container the melt can no longer flow back into the melt pool of the melt container.

Further refinements of the invention are contained in the subclaims.

With the dosing device according to the invention, the advantage is achieved that the filling and dosing process can be carried out quickly and efficiently and that the container containing the dosed melt can be easily transported and fed to other locations.

The device according to the invention will be explained in more detail by way of example with reference to the drawing.

The drawing shows a principle representation of the device according to the invention.

The container 1 for the molten metal is provided with a container cover 2, while the valves 3 are provided for the negative pressure, excess pressure and ventilation.

4 with a valve for the sealing device is designated.

A pipe system 5 projects into the container 1 and can be connected to the common inlet and outlet 9 of the metering container 8. The dosing container 8 sits on a weighing system 6 and has inside a float 7 for measuring the level.

A seal 10 is provided at the outlet of the inlet or outlet 9. With 11 a channel or an outlet is designated.

The measuring devices are connected via a transmitter 12 to an input device 13 and a process computer 14, which in turn is connected to an output unit or a printer 15 and a terminal 16. A pressure line for the nitrogen and 17 a vacuum line to the vacuum pump are designated by 17. The bearing 19 serves for emptying the metering device 8, the channel 11 or the outlet being drawn under the outlet opening of the inlet or outlet 9. The common inlet and outlet is arranged such that it begins at the bottom of the metering container 8 and at least with its inlet and outlet opening lies above the level of the filling of the metering container 8. The function of the device for dosing and transporting molten metals has the following function.

• 1. Im Behälter 8 wird ein Unterdruck erzeugt, der bewirkt, dass der über dem Schmelzbehälter 1 wirkende Luftdruck die Schmelze über das Rohrsystem 5 und den gemeinsamen Zu- und Ablauf 9 nach dem Dosierbehälter 8 befördert.
• 2. Im Behälter 1 wird ein Überdruck erzeugt, der bewirkt, dass die Schmelze in der gleichen Weise in den Dosierbehälter 8 gedrückt wird.

The molten metal, which is located in the container 1 or in a holding furnace, is conveyed into the metering container 8 via the pipe system 5 and the common inlet or outlet 9. There are two options.

• 1. A vacuum is generated in the container 8, which causes the air pressure acting over the melting container 1 to convey the melt via the pipe system 5 and the common inlet and outlet 9 to the dosing container 8.
• 2. An overpressure is generated in the container 1, which causes the melt to be pressed into the metering container 8 in the same way.

• 1. Der Behälter 8 ist zusammen mit dem Zu-und Ablauf 9 starr angeordnet, wobei das Rohrsystem 5 derart beweglich angeordnet ist, dass es je nach Bedarf mit dem Zu- und Ablauf 9 verbunden werden kann.
• 2. Das Rohrsystem 5 ist starr angeordnet, und der Dosierbehälter 8 kann dagegen so weit bewegt werden, dass, je nach Bedarf, das Rohrsystem 5 mit dem Zu- und Ablauf 9 verbunden werden kann.
• 3. Das Rohrsystem 5 sowie der Behälter 8 sind beweglich angeordnet, so dass sie bei Bedarf miteinander verbunden werden können.

So that the melt can be transported from the melting tank 1 to the dosing tank 8, the pipe system 5 must be tightly connected to the inlet or outlet 9. This can be done in several ways.

• 1. The container 8 is rigidly arranged together with the inlet and outlet 9, the pipe system 5 being arranged such that it can be connected to the inlet and outlet 9 as required.
• 2. The pipe system 5 is rigidly arranged, and the dosing container 8 can be moved so far that, depending on the need, the pipe system 5 can be connected to the inlet and outlet 9.
• 3. The pipe system 5 and the container 8 are arranged so that they can be connected to one another if necessary.

When the dosing container 8 has reached its desired filling weight, which can be determined using a wide variety of measurement methods, and the pipe system 5 has been removed at the common inlet and outlet 9, dosing of the metal in FIG. 8 can be started.

• 1. Das Metall wird über einen im Behälter 8 aufgebrachten Überdruck 9 aus dem Behälter gedrückt. Die Menge, die den Behälter verlässt, kann wieder durch die verschiedensten Messmethoden ermittelt werden. Hat die gewünschte Menge den Behälter verlassen, wird durch einen schlagartigen Abbau des Überdrucks der Ausfluss gestoppt.
• 2. Das Metall wird durch eine Schwenkbewegung des Behälters 8 über den gemeinsamen Zu- und Ablauf 9 aus dem Behälter 8 gegossen. Auch hier kann die Menge, die aus dem Behälter fliesst, auf die verschiedensten Arten gemessen werden. Hat die gewünschte Menge den Behälter verlassen, wird durch einen sofortigen Stopp der Schwenkbewegung ein weiteres Ausfliessen verhindert.

There are basically two options.

• 1. The metal is pressed out of the container via an overpressure 9 applied in the container 8. The amount that leaves the container can again be determined using a wide variety of measurement methods. Once the desired quantity has left the container, the outflow is stopped by a sudden reduction in the excess pressure.
• 2. The metal is poured out of the container 8 by a pivoting movement of the container 8 via the common inlet and outlet 9. Again, the amount that flows out of the container can be measured in a variety of ways. If the desired quantity has left the container, an immediate stop of the swiveling movement prevents further outflow.

Depending on requirements, a new filling process or a new dosing process can be initiated.

Since the dosing container 8 is not firmly connected to the pipe system 5, it can also be used as a transport container at the same time.

The entire system can be easily connected to a process computer 14, as a result of which the various weights can be dosed in any order and the individual processes can be initiated. In addition, the entire system is operated with nitrogen via the feed line 17, with all points where there is a risk of oxidation being covered with nitrogen gas, which is supplied with a slight positive pressure above the critical points in relation to the prevailing air pressure.

Claims (11)

1. Installation for measuring and conveying molten metal, consisting of a gastight container (8) having an intake and offtake, with which smelt can be removed from a smelt container (1) or holding furnace or conversely from which smelt can be conveyed, for example, into a molten bath, charac- terised in that the intake (9) is at the same time the offtake (9) of the container (8) and the common intake/offtake (9) can be connected to a pipe system (5) which is present in the smelt container (1), in such a way that, by tilting or application of an excess pressure in the container (8), the smelt present in the container (8) is conveyed wholly or partially out of the container (8), and, upon the filling operation of the container (8), the smelt can no longer flow back into the molten bath of the smelt container (1).

2. Installation according to claim 1, characterised in that the common intake/offtake (9) of the container (8) can be connected tightly to the pipe system (5).

3. Installation according to claim 1 or 2, characterised in that the container (8) together with the intake and offtake (9) is arranged rigidly, while the pipe system (5) is arranged movably in the smelt container (1) in such a way that it can, as required, be connected to the intake/offtake (9).

4. Installation according to claim 1 and 2, characterised in that the pipe system is arranged rigidly and the container (8) is movable in such a way that, as required, the pipe system (5) can be connected to the intake/offtake (9).

5. Installation according to claim 1 or 2, characterised in that the pipe system (5) and the con.. tainer (8) are arranged so as to be movable in such a way that they can, as required, be connected to one another.

6. Installation according to one or more of the preceding claims, characterised in that an underpressure can be produced in the container (8) which brings about the fact that, upon connection of the intake/offtake (9) to the pipe system (5), the air pressure present above the smelt conveys the smelt from the smelt container (1) into the container (8).

7. Installation according to one or more of the preceding claims, characterised in that an excess pressure can be produced in the smelt container (1) which brings about the fact that, after connection of the intake/offtake (9) to the pipe system (5), the smelt is conveyed towards the container (8).

8. Installation according to one or more of the preceding claims 1 to 6, characterised in that the container (8) is acted upon with an excess pressure for emptying.

9. Installation according to one or more of the preceding claims 1 to 7, characterised in that the container (8) is tiltable for emptying.

10. Installation according to one or more of the preceding claims, characterised in that all the appropriate places at which a risk of oxidation of the smelt arises are protected with a slight excess pressure of nitrogen.

11. Installation according to one or more of the preceding claims, characterised in that the common intake/offtake (9) is so arranged that it begins at the bottom of the measuring container (8) and lies at least with its inlet and outlet opening above the level height of the filling of the measuring container (8).

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