US2145416A - Apparatus for casting metals - Google Patents

Description

Jan. 3l, 1939.

D. K, CRAMPTON APPARATUS FOR CASTING METALS Filed Aug. 6, 1937 WM Z Lag

Patented Jan. 31, 1939 y APPARATUS FOR CASTING METALS Donald K. Crampton, Marion, Conn., assigner to Chase Brass & Copper Co. Incorporated, Waterbury, Conn., a corporation of Connecticut Application August 6,

7 Claims.

This invention relates to apparatus for casting metals, and more particularly to apparatus for continuously casting rods, tubes, bars, or the like.

One of the objects of the present invention is to provide simple, reliable and effective apparatus for continuously casting metals which will effectively guard a large area of the surface of the molten metal against oxidation,

A further object is to provide a superior apparatus for continuously casting rods, tubes, bars, or the like, and in which means is provided which will minimize or substantially eliminate objectionable agitation of the molten metal directly above the die or casting passage, when additional molten metal is added,

Another object of the present invention is to provide an apparatus for continuously casting metals. having superior means whereby the level of the molten metal in the container or Crucible may be readily ascertained.

With the above and other objects in view, as will appear to those skilled in the art from the present disclosure, this invention includes all features in the said disclosure which are novel over the prior art and which are not claimed by me in a separate application.

In the accompanying drawing:

Fig. 1 is a view in vertical central section of an apparatus for continuously casting metals, and in which is embodied the present invention;

Fig. 2 is a top or plan view of the said apparatus with the cover of the housing omitted; and

Fig. 3 is a perspective view of the oating shield-block.

The particular continuous-casting apparatus herein chosen for the illustration of the present invention includes a cup-shaped container or Crucible, generally designated by the reference character 2li, and which may be formed of any suitable material, such, for instance, as a claygraphite material, commonly used in the manufacture of crucibles or the like. The said container or crucible 2li includes a substantially-nat bottom-wall 2l and an upstanding annular side- Wall 22, and is preferably enclosed in a housing, generally designated by the reference character 23.

The housing 23, above referred to, includes a bottom-wall 24, an annular side-wall 25 and a removable cover 26, through which latter a charging-opening 26al is provided. The said housing 23 is preferably formed of heat-insulating material common in the metallurgical art, and serves to conserve the heat of the molten metal 21 contained within the crucible or container 20, before referred to. v

The bottom-wall 2| of the container 20 is provided with an aperture 2B in which is tted a forming-die 29 having a central aperture or forming-passage 30 for the purpose as will herein- 1937, Serial No. 157,644

(Cl. T22-57.2)

after appear. The lower end of the forming-die 29 extends a suitable distance below the undersurface of the bottom-wall 2l of the container 20 and is surrounded by a cooling-chamber 3l through which water or other suitable coolant may be passed to extract heat from the said die. The forming-die 29, before referred to, may be made of any suitable material which will withstand the heat of molten copper, brass or other metal, and it has been found that for this purpose a very fine-grained graphite is suitable.

As the molten metal 21 passes downwardly through the forming-passage 30 in the formingdie 29, it will, depending upon the speed at which it is Withdrawn, solidify within the said formingpassage, and for purpose of illustration, this solidication-zone may be considered to be at about the point marked 32 in Fig. 1 of the accompanying drawing. The required extraction of heat from the molten metal 21 as the same passes downwardly through the forming-passage 3i! in the forming-die 29, to eiect the solidiflcation thereof into the solid bar 33 shown in Fig. 1, is effected through the lower portion of the said die by the cooling-chamber 3|, before referred to.

The bar 33 may be continuously drawn downwardly by any suitable means (not shown) at such a speed as will insure the'solidication of the molten metal 21 into the bar-like form 33 before emergence from the lower end of the forming-passage 30 in the forming-die 29.

Floating upon the upper surface of the molten metal 21 is a shield-block, generally designated by the reference character 311, and which may assume various forms but in the instance shown comprises a disk-like cylindrical portion 35 and an upper conical portion 36. The said floating shield-block 34 may be made of a Variety of materials lighter than .molten brass, copper, or other metal being cast, but it is preferred to employ a carbonaceous material, such, for instance, as graphite, inasmuch as such material assists in preserving a non-oxidizing atmosphere around the upper surface of the molten metal 21. The shield-block 34 is, as shown, slightly smaller in diameter than the internal diameter of the container or Crucible 20, so that it may rise and fall with the changes in level of the molten metal 21.

When it is desired to add additional molten metal to the container or Crucible 20, the conical upper surface of the oating shield-block 3i will receive the impact of such additional metal as the same is poured into the said container through the charging-opening 26a., and will eectively guard the molten metal already in the container against undue turbulence at a point immediately above the forming-die 29, to thus guard against changes in the texture of the metal as the same is being solidified in the said die, and

also to minimize or substantially eliminate the occlusion of gas therein.

In addition to'vacting to guard the surface of the molten metal 21 against undue oxidation and guarding the metal 21 within the crucible from undue turbulence at a point immediately above the forming-die 28, the floatingshieldblock 34 also discharges a function ofindicating the level of molten metal within the container 20, so that the same may be maintained within predetermined limits most suitable for the continuous casting of the rods 33 or other continuous objects.

As above stated, the shield-block 34 will enable an observer to determine the level of the molten metal in the container, which feature is especially useful in the event that a blanket of charcoal or the like is used to seal the gap between the periphery of the said shield-block and the adjacent wall-surface of the container 20. Under such circumstances, the peak of the conical portion 36 will be caused to project into view.

The invention may be carried out in other specific ways than that herein set forth without departing from the spirit and essential characteristics of the invention, and the present embodiment is, therefore, to be considered in all respects as illustrative and not restrictive, and all changes coming within the meaning and equivalency range of the appended claims are intended to be embraced therein.

I claim:

1. An apparatus for continuously casting metal, including in combination: a container for molten metal having a forming-passage through which molten metal may be continuously withdrawn therefrom; and a oatable shield-block formed of carbonaceous materialV having a suilicientlylow specific gravity to float upon the molten metal in the said container above the forming-passage therein, to thus shield the upper surface of the molten metal against oxidation and also guard the molten metal from undue turbulence immediately adjacent the forming-passage in the said container.

2. `An apparatus for continuously casting metal, including in combination: a container for molten metal having a forming-passage through which molten metal may be continuously withdrawn therefrom; and a floatable shield-block formed of graphite having a sufficiently-low specific gravity to float upon the molten metal in the said container above the forming-passage therein, to

thus shield the upper surface of the molten metal Y against oxidation and also guard the molten metal from undue turbulence immediately adjacent the forming-passage in the lsaid container.

3. In apparatus for continuously casting metal, the combination with a container for molten metal having an opening for charging molten metal thereinto and a forming-passage wherein the molten metal is continuously solidified as it passes therethrough; a fioatable shield-block arranged below said charging-opening and above said forming-passage to form a gap of comparatively small width between the marginal edge of said shield-block and the inner wall of said container, said gap being covered by a blanket of carbonaceous material through which the molten metal passes to said forming-passage.

4. An apparatus for continuously casting metal,

comprising: a container provided with a formingdie wherein the molten metal issolidined as it is continuously discharged therethrough; and a floatable shield-block composed of material which constitutes a reducing agent for gaseous compounds of the metal being cast and has a cross-sectional area conforming to and of suitable magnitude with respect to the said container to form a comparatively-narrow inlet-opening with the inner wall of the said container to distribute the molten metal charged into the said container.

5. An apparatus for continuously casting metal, comprising: a molten-metal container provided with a relatively-largecross-sectional area which is substantially uniform in size and shape from top to bottom thereof; a tubular forming-die of relatively-small cross-sectional area extending downwardly through the bottom wall ofthe said container to receive a continuous flow of molten metal therefrom; and a. metal-distributing float composed of material constituting a reducingagent for gaseous compounds of the metal to be cast, the said float conforming to and having a cross-sectional area slightly less than that of the inner wall of the said container to form between the former and the latter a covered supply-reservoir for molten metal and to provide a marginal inlet-opening thereinto.

6. An apparatus for continuously casting metal, comprising: a molten-metal container provided with a relatively-large cross-sectional area which is substantially uniform in size and shape from top to bottom thereof; a tubular forming-die of relatively-small cross-sectional area centrally arranged with respect to the bottom wall of the said container and extending downwardly therethrough to receive a continuous flow of molten metal therefrom; a metal-distributing float conforming to and having a cross-sectional area m slightly less than that of the interior wall of the said container to form between the former and the latter a covered supply-reservoir for molten metal and to provide a marginal inlet-opening thereinto; and a floatable blanket of comminuted material which provides a reducing-agent for gaseous compounds of the metal to be cast, the said floatable blanket being arranged around and covering the said marginal inlet-opening.

7. An apparatus for continuously casting metal, comprising: a molten-metal container provided with a relatively-large cross-sectional area which is substantially uniform in size and shape from top to bottom; a tubular forming-diey of relatively-small cross-sectional area extending downwardly through the bottom wall of the said container to receive a continuous flow of molten metal therefrom; a metal-distributing float con- ,i'orming to and having a cross-sectional area slightly less than that of the inner wall of the said container to form between the former and the latter'a covered supply-reservoir for molten metal and to provide a marginal inlet-opening thereinto, the said metal-distributing float being composed of material constituting a reducingagent for gaseous compounds of the metal to be cast; and a floatable blanket of comminuted material of suitable composition to provide a reducing-agent for the gaseous compound of the metal to be cast, the Said fica-table blanket being arranged to cover the marginal inlet-opening through which the molten metal is delivered to the said covered supply-reservoir therefor.

DONALD K. CRAMPTON.

Images