US3721432A

US3721432A - Apparatus for reception and discharge of liquid metal

Info

Publication number: US3721432A
Application number: US00089778A
Authority: US
Inventors: E Buhrer; A Alt
Original assignee: Georg Fischer AG
Current assignee: Georg Fischer AG
Priority date: 1969-11-18
Filing date: 1970-11-16
Publication date: 1973-03-20
Anticipated expiration: 1990-03-20
Also published as: DE2050933B2; CH516362A; BE758998A; CA928033A; DE2050933A1; FR2067355A6; JPS5014220B1; SE370649B; GB1327277A; DK132208B; DK132208C; FR2067355B1

Abstract

A heating means and a feed container having a feed cavity therein are both coupled to a container which is adapted to receive and discharge liquid metal. The reception and discharge container includes a valve operated opening for selectively pouring out the liquid metal. A feed channel is provided between the lower end portions of the feed cavity and the container cavity such that liquid metal poured into the feed cavity flows into the container cavity through the feed channel. The feed container has a wall the height of which is equal to the maximum level of liquid metal in the container cavity such that when the liquid metal reaches the desired maximum level, the excess liquid metal is poured off over the wall.

Description

United States Patent Buhrer et al.

APPARATUS FOR RECEPTION AND DISCHARGE OF LIQUID METAL Inventors: Erwin Buhrer, Schaffhausen, Switzerland; Anton Alt, Metzkausen, Germany Assignee: Georg Fischer Aktiengesellschaft,

Schaffhausen, Switzerland Filed: Nov. 16, 1970 Appl. No.: 89,778

Foreign Application Priority Data Nov. 18, 1969 Switzerland ..l7l3l/69 References Cited Tagiaferri 4.13/29 2,427,817 9/1947 Tama ..l3/29 1,796,871 3/1931 Madorsky ..266/37 UX 2,586,596 2/1952 Bahney 13/29 2,892,878 6/1959 Tostmann. l3/29 3,005,858 10/1961 Lang ..l3/29 Primary ExaminerJ. Spencer Overholser Assistant Examiner-John S. Brown Attorney-Flynn & Frishauf [57] ABSTRACT A heating means and a feed container having a feed cavity therein are both coupled to a container which is adapted to receive and discharge liquid metal. The reception and discharge container includes a valve operated opening for selectively pouring out the liquid metal. A feed channel is provided between the lower end portions of the feed cavity and the container cavity such that liquid metal poured into the feed cavity flows into the container cavity through the feed channel. The feed container has a wall the height of which is equal to the maximum level of liquid metal in the container cavity such that when the liquid metal reaches the desired maximum level, the excess liquid metal is poured off over the wall.

13 Claims, 4 Drawing Figures PATENTEUmzomn SHEET 10F a PATENTEUHARZOIEJH SHEET 30F 3 Fig. 4

APPARATUS FOR RECEPTION AND DISCHARGE OF LIQUID METAL The present invention relates to an improved apparatus having a container for the reception and discharge of liquid metal which is equipped with a device for heating the liquid metal and a stopper mechanism at the pouring outlet, and more particularly to such an apparatus having an improved filling arrangement.

Molding and casting equipment is known in which the pouring apparatus is provided with a container for reception and discharge of liquid metal, the container having on its underside a pouring outlet which can be closed with a stopper. These containers also include filling ports for the liquid metal. There are also known types in which, instead of having filling ports, the curved top of the container may be lifted and tilted for filling.

In molding and casting installations it is unavoidable that interruptions of operation take place. These interruptions may be caused by regular work breaks, by operational breakdowns, change of mold, etc. If for example a liquid metal is poured out, as in the case of spherical graphite'iron containing traces of magnesium, the resulting material will be spherical graphite iron only if the residual magnesium content is retained over a long period of time. This is not possible with presently known apparatus. In the known apparatus, one an operational interruption exceeds minutes, it is necessary to repeat the magnesium treatment because the residual magnesium content is no longer of the necessary magnitude.

It has further been observed that a decrease in quality may occur, especially during operational interruptions, in case the molten metals contain constituents that easily react with atmospheric air or slag.

Furthermore, the indispensable slagging-off operation for the removal of slag that forms or is introduced with the liquid metal constitutes work that, when presently known containers are utilized, is always disagreeable and entails high heat loss.

Experience has further shown that reactions between the slag and the furnace lining reduces the durability of the furnace lining. These undesirable reactions become more pronounced as the temperature of the liquid metal in the container rises.

It is the object of the present invention to eliminate these disadvantages of the prior art apparatus.

SUMMARY OF THE INVENTION The apparatus for the reception and discharge of liquid metal includes a container, a heating device, and

a feed container alongside the heating device. A feed passage is provided at the lower portions of the container cavity and of the feed cavity for flow of liquid metal to the container.

The above and other objects and features of the present invention will become apparent from the following detailed description taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a cross section of the container and feed arrangement of the present invention taken along line I I of FIG. 3;

FIG. 2 is a cross section of the container and of the heating unit of the present invention taken along line II-II of FIG. 3;

FIG. 3 is a top view of the container; and

FIG. 4 is a section of the feed opening taken along line IVIV of FIG. 3.

FIG. 1 illustrates a preferred embodiment of the present invention. A container 1 having a cavity 7 therein is detachably connected with a feed container 2 by means of a joint 5. Joint 5 is not further described herein. Its design should be apparent to those skilled in the art. The feed container 2 has a feed cavity 3 formed therein and has at its upper end a pouring-in opening 6. Feed container 2 is at its lower end connected with the container cavity 7 by means of an inclined feed passage or channel 4. The angle of inclination a of feed channel 4 is preferably approximately equal to the angle of inclination B of the heating channel 12 illustrated in FIG. 2. By virtue of this arrangement, an equal level is reached in feed cavity 3 and in heating channel 12 when the container cavity 7 is emptied. On the upper side of container 1 a valve device 8 is provided, which comprises a hermetically closing cap 9 and a slide valve member 10.

Maximal fill level 18 of the liquid metal in container cavity 7 is the same level as rim 19 (see FIG. 4) of pouring opening 6 of feed container 2.

FIG. 2 illustrates the container 1, which is detachably connected with a heating unit 11. Heating unit 1 1 comprises a heating channel 12, which is directly connected with container cavity 7, also at the lower portion of cavity 7. A stopper bar 13 (already known per se) is mounted in container 1 and cooperates with the valve seat 14, as is well known. A seal 15 for the stopper bar 13 is provided in the curved upper wall of container 1 where the stopper bar 13 enters the container 1 to seal out the ambient atmosphere from container cavity 7. An opening 20 is provided to permit connection with a vacuum pump (not shown in the drawings) or connection with a gas intake (also not shown in the drawings).

FIG. 3 illustrates a top view of the arrangement of container 1 with feed container 2 and heating unit 11. Feed container 2 and heating unit 11 are arranged on the same side of container 1, so that when shutting the apparatus down, it is possible to simultaneously empty heating channel 12 and the feed channel 4 by tilting the container 1.

FIG. 4 illustrates a sectional view of feed container 2 taken along line IVIV of FIG. 3, showing the feed opening 6, feed cavity 3, feed channel 4, rim 19 and slag overflow 17.

The mode of operation of the apparatus of the present invention will now be described. Liquid metal is introduced into the container 1 through the feed opening 6 until the liquid metal rises to the level of the rim 19 (FIG. 4) of feed opening 6. This level is the same as the desirable maximal fill level 18 (FIG. 1) of the liquid metal within the container cavity 7. By virtue of the fact that feed container 2 is formed with a feed cavity 3, the slag contained in the liquid metal does not reach container cavity 7, but flows'off over the rim 19 of the feed opening 6 after the container 1 is filled to the level 18. The result is that no slag gets into container cavity 7. Thus, it is possible to introduce additives or alloying elements into the liquid metal contained in the container cavity 7 by way of the valve 8 which is installed in the wall of container 1. The additives or alloying elements may display a lower specific gravity than the liquid metal when the present invention is used. A suction pump may be fitted over opening 20 so as to create a pressure (negative) in container cavity 7. However, it is also possible to introduce through opening 20 an inert gas or other gaseous agent, so as to prevent an alteration of the liquid metal inside the container and/or to induce and/or control the liquid metal and its reactions in some specific way.

Thus, the arrangements of feed cavity 3, container cavity 7 and lower feed channel 4 provides a self-leveling system whereby the liquid level in the feed cavity 3 and container cavity 7 seek the same level. This is similar to an inverted siphon arrangement.

The desired temperature of the liquid metal in container l is maintained by the attached heating unit 11, which may also operate with well known automatic temperature regulation.

Constant maintenance of a desired temperature in liquid metals through the incorporation of an inductive heating apparatus, and the simultaneous prevention of the leaking in of air from the ambient atmosphere and of the leaking in of slag into container cavity 7 by virtue of the use of the feed cavity and lower feed channel combination, permits normal treatment of liquid metals whose composition may vary, such as, for example, magnesium-treated iron for spherical graphite iron. Normal casting can be carried out even after a fairly long interruption of operations without losses in quality and without the necessity of conducting a repeat treatment operation.

In addition, the siphon-type feed opening makes it possible to eliminate the maintenance operation of slag removal from-the container 1 altogether, because any slag introduced with the liquid metal into feed cavity 3 is automatically separated off over rim 19 of the feed opening 6.

Because the liquid metal is already slag-free in the container 1, it is possible to introduce alloying constituents or other elements into the molten metal, even if the additives have a lower specific gravity than the liquid metal.

Tests indicate that by virtue of the present apparatus, the life-span of the container lining, of the stopper seal 15, and of the stopper pouring opening 14 is considerably increased.

Because the maximal fill level of the liquid metal 18 in the container 1 is limited by the height of the rim 19 of the feed opening 6, and the fill level in the feed cavity 3 of the feed container 2 can be visually observed and controlled, there is no further need for the prior art types of feed control that was hitherto performed by means ofa rocker-type mechanism.

Finally, it should be pointed out in addition to the above advantages, it has been found that the heat losses of the containers are significantly reduced. These heat losses must be replaced by means of heat added by inductive heating. Thus, less heat must be added with the present invention.

A container in accordance with the present invention permits, by means of coupling a vacuum pump to opening 20, the reduction of the gas content of the liquid metal. As mentioned above, a gas can also be introduced through the provided opening 20 so as to control the atmosphere in the container cavity 7.

Various modifications may be made to the illustrated embodiment Within the scope of this invention as set forth in the accompanying claims.

We claim:

1. Apparatus for the transfer of liquid metal, subject to slag formation, to casting molds comprising:

a closed container (1) having a cavity (7) therein for receiving liquid metal and isolating the metal from ambient air, said container (1) being formed with a pouring opening (14) located at a lower end portion thereof and stopper means (13) for selectively opening and closing said pouring opening to selectively permit liquid metal to flow from the container by gravity;

heating means (11) coupled to said container cavity (7) for heating the liquid metal therein;

a feed container (2) having a feed cavity (3) therein, said feed container (2) being coupled to and in liquid communication with said liquid container (1); said feed cavity extending at least as high as the desired maximal liquid level in said container cavity (7) and said feed container having an overflow rim (19);

a feed channel (4) coupled between the lower end portion of said feed cavity (3) and the lower end portion of said container cavity (7) and forming said liquid communication, such that liquid metal poured into said feed cavity (3) flows into said container cavity (7) through said feed channel (4) and liquid metal can be stored in the container free from contact with ambient air, and removed from the container by direct flow through the pouring opening.

2. Apparatus according to claim 1 wherein said feed channel (4) is downwardly inclined from said container cavity (7) to said feed cavity (3).

3. Apparatus according to claim 1 comprising a heating channel (12) coupling the lower end portion of said container cavity (7) to said heating means (1 1).

4. Apparatus according to claim 3 wherein said heating channel (12) is downwardly inclined from said container cavity (7) to said heating means (1 1).

5. Apparatus according to claim 4 wherein said feed channel (4) is downwardly inclined from said container cavity (7) to said feed cavity (3).

6. Apparatus according to claim 5 wherein the angle of downward inclination of said heating channel (12) is approximately equal to the angle of downward inclination of said feed channel (4).

7. Apparatus according to claim 1 wherein said heating means (12) and feed container (2) are located alongside each other and on the same side of said container (l).

8. Apparatus according to claim 6 wherein said heating means (12) and feed container (2) are located alongside each other on n the sameside of said container (l).

9. Apparatus according to claim 1 wherein said feed container (2) includes a wall having said rim (19) located at an overflow level corresponding to the maximum allowable liquid metal level (18) in said container (l such that when said liquid metal reaches said maximum level (18), further liquid metal poured into said feed container (2) will overflow said wall, and slag will also overflow said wall.

10. Apparatus according to claim 1 wherein said stopper means comprises a stopper bar (13) passing through a wall of said container (1), and further comprising sealing means coupled to said container for container (1) includes a valve type opening formed in a wall thereof for introduction of additives or the like to said liquid metal.

13. Apparatus according to claim 2 wherein the bottom of said feed cavity is below the level of the bottom of said container cavity.

Claims

1. Apparatus for the transfer of liquid metal, subject to slag formation, to casting molds comprising: a closed container (1) having a cavity (7) therein for receiving liquid metal and isolating the metal from ambient air, said container (1) being formed with a pouring opening (14) located at a lower end portion thereof and stopper means (13) for selectively opening and closing said pouring opening to selectively permit liquid metal to flow from the container by gravity; heating means (11) coupled to said container cavity (7) for heating the liquid metal therein; a feed container (2) having a feed cavity (3) therein, said feeD container (2) being coupled to and in liquid communication with said liquid container (1); said feed cavity extending at least as high as the desired maximal liquid level in said container cavity (7) and said feed container having an overflow rim (19); a feed channel (4) coupled between the lower end portion of said feed cavity (3) and the lower end portion of said container cavity (7) and forming said liquid communication, such that liquid metal poured into said feed cavity (3) flows into said container cavity (7) through said feed channel (4) and liquid metal can be stored in the container free from contact with ambient air, and removed from the container by direct flow through the pouring opening.

3. Apparatus according to claim 1 comprising a heating channel (12) coupling the lower end portion of said container cavity (7) to said heating means (11).

4. Apparatus according to claim 3 wherein said heating channel (12) is downwardly inclined from said container cavity (7) to said heating means (11).

7. Apparatus according to claim 1 wherein said heating means (12) and feed container (2) are located alongside each other and on the same side of said container (1).

8. Apparatus according to claim 6 wherein said heating means (12) and feed container (2) are located alongside each other on n the same side of said container (1).

9. Apparatus according to claim 1 wherein said feed container (2) includes a wall having said rim (19) located at an overflow level corresponding to the maximum allowable liquid metal level (18) in said container (1), such that when said liquid metal reaches said maximum level (18), further liquid metal poured into said feed container (2) will overflow said wall, and slag will also overflow said wall.

10. Apparatus according to claim 1 wherein said stopper means comprises a stopper bar (13) passing through a wall of said container (1), and further comprising sealing means coupled to said container for sealing the passage in said container wall through which said stopper bar (13) passes.

11. Apparatus according to claim 1 wherein said container (1) includes a controllable opening means (20) for controlled introduction or evacuation of gases from said container cavity (7).

12. Apparatus according to claim 1 wherein said container (1) includes a valve type opening formed in a wall thereof for introduction of additives or the like to said liquid metal.