DE2616685A1 - METHOD AND DEVICE FOR CONTINUOUS METAL CASTING - Google Patents

Description

(The priority from Japanese Patent Application 64045/1975, filed May 30, 1975 is claimed)

The invention relates to a method and apparatus for continuously casting molten metal from only one Oven. A funnel with several openings picks up the molten metal and passes it on. One of the nozzles is from below closed by a plug and this opening or nozzle is made with a mixture of silica and carbonaceous Material filled, which is washed away by the molten material after removing the stopper from the nozzle. Point of time the opening of the nozzle is determined to coincide with the cyclic output of the furnace.

With the aid of the method according to the invention, one is continuous successive casting operation possible in which molten metal is fed from a melting furnace Volume or the amount of molten material per time

S098S0 / 0621

Models sent in will be destroyed after 2 months if not reclaimed. Oral agreements, especially by telephone, require a written one Confirmation. - The costs invoiced are due on the invoice date without deduction. - In the event of late payment, bank interest will be charged.

ORIGINAL

- 2 - April 14, 1976

that is, that or _o that reaches the casting molds through the nozzles of at least one funnel is set accordingly.

In order to increase productivity, reduce production costs and save labor through a continuous casting process, the so-called successive casting operation, which is well known to those skilled in the art and which is generally applied. When performing such casting operations, several furnaces are generally used, of which aas molten metal got into the pouring device !; the timing of the taps of the melting furnaces is controlled or regulated so that the molten metal without substantial Interruption in the funnel of the pouring device.

When carrying out the so-called successive casting process using only a single melting furnace, the melting capacity of the furnace can often not be used to the maximum because the casting capacity of the associated casting device is set in such a way that a predetermined cast quantity is fixed in the unit of time _{o by 1} both the melting capacity of the melting furnace as well as at the same time optimally utilizing the capacity of the casting device connected therewith, further factors must be taken into account, by means of which the casting amount per unit of time is regulated in the casting device

When the molten metal during the continuous casting process passes through the nozzles of the funnel into the casting molds, the casting speed or casting amount per unit of time when using water-cooled casting molds on the basis of various parameters such as cross-section of the strands produced, temperature of molten metal, amount of cooling water, etc. determined empirically. As a result, casting methods that deviate significantly from this empirical range are for the practice unsuitable.

609850/0621

- 3 - April 14, 1976

If, therefore, the casting of several strands with a continuous, equipped with at least one funnel with several nozzles, which is in communication with only one melting furnace Casting device is to be carried out, it is important for an uninterrupted successive casting operation that the Number of streams of molten metal flowing through the funnel get into the molds, change appropriately during the casting process. With such a real change stands the maximum number of consecutive without interruption produced strands in accordance with the capacity of the melting furnace which delivers the molten material to the caster In other words, the casting time provided for the casting device or the amount of the molten metal to be poured into the device is required becomes in agreement The number of moldings or castings that is set with the time cycle of the output of the furnace can be changed during a casting process, for example by opening or closing each one appropriately Nozzle holes of the funnel with the help of plugs, which are arranged inside the funnel. This method yields however, there is a problem in that when a certain nozzle is closed for a relatively long time, there is a problem that the stone forming the head of the plug fuses with the nozzle stone due to the heat of the molten metal, which prevents that the process can be carried out in the desired manner.

According to the invention, a method and a device are now intended proposed, with which the disadvantages inherent in previous working methods and devices are eliminated,

The invention is therefore a method for continuous casting with the aid of a casting device, which

609850/0621

- 4 - April 14, 1976

molten metal is fed from a melting furnace. This method is characterized in that at least one of the nozzles, which are arranged in the interior of at least one funnel, is closed from below by means of a stopper and that the inner and upper part of the closed nozzle is filled with a filler material which .des molten metal from the nozzle is regulated, whereupon the stopper is removed after a predetermined period of time so that the nozzle is opened the output cycle of the furnace, or that the amount of molten metal to be poured by the device is adjusted in accordance with the cyclic output of the furnace _o The casting process can be so smooth and continuous with the successive output of the furnace in Bring agreement.

The invention also relates to a casting device for carrying out the method described above, which at least has a funnel with a plurality of nozzles, at least one of which is filled with a filling material inside and of is closed at the bottom with a stopper. «The nozzle is opened after a predetermined period of time when the. plug Will get removed. The filling material is flushed out of the nozzle by the pressure and the passage of the molten metal, so that the molten metal can then flow freely through the nozzle without melting the nozzle.

The objects of the present invention also include a filler material which is inside a nozzle of a funnel is arranged and which the outflow of the molten metal from the nozzle in cooperation with a stopper that the nozzle closed from below, regulated. The filler material is under

609850/0621

- 5 - April 14, 1976

the effect of the pressure and the passage of the molten Metal placed in the funnel is easily washed away from the nozzle after the stopper is removed from the nozzle is.

To further explain the present invention, reference is now made to the accompanying drawings. It is expressly stated pointed out that in the drawings only an exemplary embodiment of the various possible embodiments of the invention is shown. In the drawings:

Figure 1 is an enlarged partial cross-section through a funnel with a nozzle, which in the manner according to the invention is locked;

Figure 2 is a schematic view, partly in section, of a continuous casting furnace including one Funnel according to the present invention.

The preferred embodiment of the present invention illustrated in the drawings is described in greater detail below explained.

If one first looks at FIG. 2, one recognizes a funnel 1 which is held by a movable frame 2. The frame 2 has support girders 3 which, in turn, are equipped at their lower ends with wheels 4 which rest on horizontal rails 5 to run. The rails, in turn, are on a solid frame (not shown) attached.

As shown in the drawing, the funnel 1 has an outer shell 6 made of sheet metal with side walls and a bottom. A lining. 7 made of refractory material is in the outer

609850/0621

- β - April 14, 1976

Shell 6 attached. Several can be seen at the bottom of the funnel 1 Casting nozzles 9 through which the molten metal flows from the funnel 1 into the molds 8 below. Above that Funnel 1 is a pouring bucket 10 for molten metal suspended in the usual ¥ ice

One of the nozzles of the hopper 1 is in the closed state, d _o h. shown provided with a plug 11. Before the preheating of the interior of the funnel 1 is started in the manner customary in continuous casting, at least one of the nozzles is closed in the manner shown.

If one now looks at FIG. 1, one recognizes the outer shell 6 and the Äierfeste lining 7 at the bottom of the funnel 1 and the stone 13 supporting the nozzle. Sin D-üsenstein 14 with nozzle hole 15 is in communication with an opening 16 in the refractory material 7. The plug 11 is made of metal and has a Rod 12 and a conical head 17, the latter being insertable into the nozzle hole 15 of the nozzle block 14 from below is so that the conical surface of the head 17 is in linear contact with the inner surface of the lowermost part of the nozzle hole 15 is brought, whereby the lower part of the same is firmly closed. Then a mixture of silica and a coal-like material (e.g. coke powder), which has previously been produced, is placed in the space 16 of the nozzle hole 15, after this has been closed from below by the plug 11. Then the funnel 1 is from the inside in the usual Way, in order to prepare it for the reception of the molten metal from the melting furnace.

The molten metal, which is kept at a suitable temperature, is then transferred from the melting furnace into the hopper, which is now ready to pour the molten metal.

609850/0621

- April 7-14, 1976

The molten metal is closed by the nozzles 9, which are then no longer closed by the stopper 11 and the filling material 18 are poured into the molds.

The length of time that a nozzle is closed is determined based on the amount of discharge as well as the production cycle of the molten metal through a specific melting furnace (i.e. the ejection cycle from one tap hole to another) calculated.

After the end of the period of closure of the nozzle by the plug 11, the filling material 18, which is inside the nozzle 9 is under the action of the pressure of the continuous molten material present in the hopper, removed. The molten metal then flows freely into the mold under the newly opened nozzle 9, so that a new casting process begins. In this way, an additional amount of molten material coming from the same furnace will be passed through the same hopper, which means that there is an improved, sequential, continuous Casting process results.

The mixture of silica (silica sand) and the coal-like Material used as filler material 18 is neither under the action of the heat of the molten metal eroded still fused with the nozzle block 14. By this filling material 18 in connection with the retaining force of the stopper 11, which closes the lower part of the nozzle, is the outflow of molten .metal in a simpler and more effective way! "Teise prevented. After opening the closed nozzle, the molten metal flows out of the now open nozzle in an extraordinarily smooth manner.

• The implementation of the method according to the invention should now be based on

6098SO / 0621

- April 8-14, 1976

a working example will be explained.

example

Molten metal (steel) was poured at a rate of 0.2 tons per minute per strand using the caster cast in accordance with the present invention. There were 4 strands of 125 mm square bars from the melted Metal produced by an electric 60 ton steel furnace with a cyclic output capacity of 63 tons was generated. The tapping cycle of the 60 ton furnace was 90 minutes ο At the beginning of the operation, one of the four nozzles of the Hopper 1 is closed for the first 45 minutes, this time period being calculated on the basis of the explanations above had been. The other 3 nozzles remained open. After 45 minutes, the closed nozzle was opened and into the the following 45 minutes the molten metal was continuously poured through all four nozzles into the molds without interruption, there was a successive connection to the following production cycle of the furnace; there was such a successive one Casting operation.

The proof is provided by the following equation: (0.2 t per minute per strand) χ (45 minutes χ 3 strands + 45 x 4 strands) = 63 tons. The pouring rate could be so in accordance with the output and brought to the tapping cycle of the melting furnace. In the above example, the filler material 18 consisted of a mixture of about 1.5 kg of silica sand and about 1.8 kg of coke powder.

In the above description and in the working example, there is only talk of an oven equipped with a funnel However, if the furnace has an output capacity that is large is enough that an amount of molten material sufficient for more than one funnel is produced, so can multiple hoppers used in conjunction with a melting furnace

609850/0621

- April 9, 1976

will.

With the aid of the method according to the invention using the device according to the invention, you can see the amount and duration of casting regulate the molten material through the nozzles of the funnel by opening and closing the nozzles. To this Way, it is possible according to the invention, the total casting time Apparatus in accordance with the tapping cycle of the furnace that supplies the molten metal for the hopper bring to.

Thus, the present invention enables successive casting operations to be performed smoothly without interruption and drawing also have the following advantages:

1) Improvement of the product yield and the molten one Metal. If the casting is carried out in a non-consecutive manner, the initial and End portions of each strand are severed after the casting process has been completed. With the help of the invention Process can be carried out sequentially a continuous casting of strands, so that the need the frequent separation of the head and tail parts no longer exists, which significantly improves the product yield.

2) Saving in production costs.

The continuous casting method of the present invention does not require various materials such as Nozzle stones, refractory cooling blocks in the casting molds, fuel oil for preheating the funnel, etc. i.e., non-continuous casting operations are required. The present invention thus enables Saving of the resulting costs.

609850/0621

- April 10, 1976

3) Work spam.

A. Carrion that can be poured continuously, enables the saving of preparatory work such as frequent use of the starting rods, etc., so that a labor saving is achieved.

609850/0621

Claims (7)

Claims ; 1.) Continuous casting process for molten metal J using a device in which a furnace is equipped with a funnel provided with several openings, characterized in that first at least one of the nozzles is closed with the aid of a plug, then the closed nozzle to prevent the passage of molten metal is filled with a filler material which has been prepared beforehand by mixing certain materials, so that a metal melt in the nozzle is prevented during the closing of the same, and that finally the one nozzle is opened again after a predetermined period of time so that the molten metal can flow through. 2.) Continuous casting process according to claim 1, characterized in that that the plug is inserted into the nozzle from below. 3.) Continuous casting process according to claim 1, characterized in that SJUciundioxidsand and carbon-like material mixed together and used as filler material. 609850/0621 -J (I - H. April 1976 4.) Continuous casting process, according to. Claim 1, characterized in that that the predetermined side span is selected so that the casting duration with the cyclical output of the Melting furnace in accordance with st & t. 5.) Apparatus for continuous pouring of molten material using a melting furnace, consisting of a container for molten metal, at least one funnel with several bit openings, the molten metal can be received S @ r ^j BäseEöffaimgen and sinsia Füllnatsrialj welsiiss in a versofelesseaen base is arranged -dnc through, äas melted metal after latferaung the stopper -? Egspül "oar is * 6.) Device according to claim 5 »characterized in that üaß äer Plug under äem Büsenloea is arranged so that the nozzle can be closed from below. 7.) Goal direction aach claim 5? characterized in that the filler material made from a mixture of silicon dioxide and carbonaceous material. PlIr Funabashi Steel Works Ltd., 2-1, 2-chome, Minamikaijin, Funabashi-Gi ty, Ohiba Prefecture, Japan Heissner & BoIte Patent attorneys 60885 0/0621 Empty soap