US1944611A - Nozzle for pouring molten metal - Google Patents

Description

Jan. 23, 1934. L. F. REINARTZ ET AL NOZZLE FOR POURING MOLTEN METAL Filed Jan. 13, 1950 2 Sheets-Sheet 1 552m" A 0221,; y QMZM lf/VENTOR.

Qwum- A TTORNEYS Jan. 23, 1934. L. F. REINARTZ ET AL NOZZLE FOR POURING' MOLTEN METAL 2 Sheets-Sheet 2 Filed Jan. 13, 1930 P227 N'II/ENTOR. By M Q A TTORNE Y.

Patented Jan. 23, 1934 UNITED STATES PATENT OFFICE 1,944,611 NOZZLE FOR POURING MOLTEN METAL corporation of Ohio Application January 13, 1930, Serial No. 420,559

11 Claims.

Our invention, while having other uses, is addressed primarily to the provision of a new type of nozzle for bottom pouring ladles, such, for example, as are used in casting ingots from charges of molten metal from the open hearth, electric or other steel melting furnaces and it will be described in this connection, it being understood that our invention has other applications.

The object of our invention is fundamentally to provide a nozzle which will pour a better stream for ingot casting. More specific objects of our invention are the provision of a nozzle elongated in cross-section, which can be matched with the major axis of the cross-section of the mold into which the stream is flowing, together with other means also for producing a quieter stream.

These and other objects of our invention which will be set forth hereinafter or will be apparent to one skilled in the art upon reading this specification, we accomplish by that certain construction and arrangement of parts of which we shall now describe a preferred embodiment, references being had to the drawings which accompany this specification.

In the drawings:-

Figure I is a sectional view of a portion of a ladle showing our nozzle member in position, showing also the plug, and a'mold to indicatethe relationship of mold nozzle and ladle during the pouring.

Figure II is a cross section taken on the section lines 4-4 of Figure I.

Figure 11A is a plan view of our nozzle in upright position.

Figure 11B is a sectional view therethrough along the major axis.

Figure 110 is a sectional view through our nozzle along the minor axis.

Figure IID is a view of our nozzle from beneath.

Figure III shows the manner in which our nozzle fits into the nozzle plate of a ladle.

In the broad aspect of our invention, we provide a nozzle which has an orifice elongated in cross-section, and in using this nozzle for the pouring of molten metal, we orient the major axis of the nozzle orifice to the major axis of the mold. Various types of elongated orifices may be employed in the practice of our invention, but among the other possible shapes we prefer to use an oval orifice. The rounded edges contributed to the quietness of the stream; and we have, in general, found an oval orifice advantageous in use over, for example, an elongated rectangular orifice. We have discovered that an elongated orifice matched to the elongation of the mold section, is

of great advantage in the pouring of ingots. It produces less spurts and sprays, a very much quieter stream, less swaying, fewer bugs, and fewer scabs. It is possible to employ a nozzle with a straight oval or other elongated orifice there- 0 through; but in our work, we have found that there is a tendency in such nozzles to produce a flare in the stream when passing from part to full stream. This flare is probably due to the action of the stopper head or plug on an elon- 5 gated orifice, as well as to the nature of the orifice itself. It can be bettered somewhat by the useof special types of plugs adapted to the orifices used; but it is difficult to keep elongated plugs properly oriented in the ladle, and the correction, in any event, appears not to be perfect.

Accordingly, we have developed a type of nozzle having an elongated pouring orifice which is developed from a round orifice in the top of the nozzle, which will satisfactorily operate with the usual round plug or stopper head. Naturally, in developing an ellipse from a circle, a tapered bore results, which tapered bore has an additional effect in quieting the stream, as will hereinafter be pointed out.

In our preferred form of nozzle, we prefer to keep the area of the oval or other elongated orifice, equal to the area of the round or other shaped orifice for the entrance of metal at the top' of the nozzle. Thus, we may develop our nozzle from a round entrance orifice to an oval exit orifice of the same area, or from a square entrance orifice to a rectangular elongated exit orifice of the same area. When this is done,--as hereinabove pointed out, a tapered bore is produced through the body of the nozzle, and this tapering bore, while it does not exhibit sub.- stantial, if any, change in effective area throughout its length, nevertheless produces a certain venturi eifect which relieves the force and pressure of the stream to an observable extent, and 1 makes it very much quieter. It is not necessary to keep the areas of exit and entrance orifices the same. Added venturi effect and alleviation of stream pressure may be produced by making the exit orifice larger; but there is a limit beyond which this is of any advantage in quieting the stream. The exit may, of course, be made smaller if desired; but this has the effect of increasing the force and pressure of the stream, has a tendency to increase splashing, and decrease the life of molds and stools.

We have conducted an investigation of the effects of increasing or decreasing the length of nozzles, which we may summarize as follows:

. orifice 13 elliptical or oval.

the best pouring conditions were produced by a tapered oval nozzle of our invention, which was approximately 15" in length; but very nearly as good results were produced by a 12'-' nozzle of the same design. A 9" nozzle, while show-. ing a very decided improvement overth'e ordinary round nozzle of the same length, did not produce results comparing with the longer types. Nevertheless, there are some disadvantages in a very long nozzle. It necessitates a bulky bushing on the bottom of the ladle, and offers the possibility of some trouble in bleeding and burning a cold heat. The 12" nozzle does not have the first .disadvantage, and presents the second in a lesser degree, while offering the advantage of working with a shallower well, which is an improvement in pouring practice. Each of the longer nozzles showed an almost equal decrease .in pouring pressure, and a substantially equally well directed and steady pouring stream. For these reasons, in commercial operation, we have standardized upon a 12" nozzle made as we shall now specifically describe.

In Figure I we have shown the usual ladle 1 for molten metal, lined with refractory material 2. The refractory material and the ladle casing are perforated at one point near the bottom to accommodate a nozzle 3, which rests in a nozzle plate or supporting member 4. The upper entrance orifice of the nozzle is situated in a depression or well 5 and a refractory lining of the metal, and it is closed by a plug or stopper head 6, manipulated by a rod 7 encased in refractory materials 8. The stream issuing through the nozzle falls into a mold .9, above which the ladleiscarried by a crane for pouring.

The nozzle 3 is a refractory body having the ordinary depression or nozzle well 10 at its upper end within which the plug or support head seats. The nozzle, itself, may be substantially cylindrical in its outer surface. At the bottom of the well or depression 10, the bore 11 or the nozzle begins. Its upper orifice 12 is, in our preferred form, round, and its lower In Figure IID the line AA,indicates the major axis of the oval exit orifice, while the line BB indicates the minor axis thereof. In order to locate the nozzle properly in theladle, the lower end of it is given a taper as at 14, and the nozzle seats in a corresponding taper 15 in the lower part 16 of the nozzle plate 4, which isattachedto the ladle casing. In order to facilitate the orienting of the major axis of the nozzles exit orifice to the major axis of a mold, a groove 17 is cut in the portion 16 of the nozzle plate, and an expanding bead 18 is formed on the tapered portion of the nozzle. Thus, when the tapered portion of the nozzle is let into the nozzle plate, and the nozzle is rotated until the body seats in the groove, the nozzle itself will be found to be correctly oriented in the ladle. Figures HA and show very clearly the manner in which the barrel portion 11 of the nozzle tapers from the round entrance orifice 12 to the elliptical orifice heat. We produce an oval stream which hangs" closely together and is very compact. This is valuable irrespective of the type of mold into which the steam is directed; and the advantages of pouring a stream of this type rather than the old wavering round stream, are obvious. Our nozzle does not produce any flaring of the stream 1 on passing from initial pour to full pour, or from ,full pour to feeding up and topping off.

Due to the venturi effect as hereinabove explained, and which, where the entrance and exit orifices of the barrel are equal in area, appears 5 to be due to the tapering of the barrel, we have decreased the static pressure of the stream, eliminated gushing, and produced a soft pouring stream. We have decreased p on the nozzle head to such .an extent that the pouring rigging can be opened and shut with little or no effort, thus greatly facilitating the manipulation of the stream. Due to the construction of the nozzle plate, and the cooperating parts of our nozzle, we achieve true setting thereof without effort, 9 and due to this same construction, we have substantially no trouble with end spalling and breaking, with consequent sloppy pour. Nor do we have any trouble with a skull in the ladle. For example, in ordinary pouring, a 4000 pound skull in the ladle presents a severe-problem. When using our nozzle it constitutes no disadvantage at all. 1

Our nozzles, in commercial use, have given uniformly good results of the kind .hereinabove noted. When, for any reason, a round nozzle of the type hereinafter used is substituted for our nozzles, our chart indicating ingot surface defects in commercial practice, immediately shows a marked increase. We have never found a nozzle of our invention that did not hold its original shape regardless of the temperature, grade, or amount of metal being poured.

It will be understood that various modifications may be made in our nozzles without departing 11. from our invention.

Having thus described our invention, what we claim as new and desire to secure by Letters Patent, is:-

1. A nozzle for pouring molten metal, which 0 has an entrance orifice having substantially equal axes, and a discharge orifice which is elongated in one direction, the area of the two orifices being substantially the same.

2. A nozzle for pouring molten metal having substantially in axial alinement a round entrance orifice, and an unrestricted elliptical discharge orifice.

3. A nozzle for pouring molten metal having substantially in axial alinement a round entrance 13E orifice, and an unrestricted elliptical discharge orifice, the bore of said nozzle tapering from the cross-section of the entrance. orifice to the crosssection of the exit orifice.

4. A nozzle for pouring molten metal having a round entrance orifice, and an elliptical discharge orifice, the bore of said nozzle tapering from the cross-section of the entrance orifice to the cross-section of the exit orifice, the area of the exit and entrance orifices being substantially 14 the same.

5. A nozzle for pouring molten metal having a round entrance orifice, and an elliptical discharge orifice, the bore of said nozzle tapering from the cross-section of the entrance orifice to the crosssection of the exit orifice. the area of the exit and entrance orifices being substantially the same, the said nozzle being about 12" in length.

6. A nozzle for pouring molten metal, comprising a piece of refractory material with a sub- 15 stantially conical depression in its upper surface, forming a well, the body of said piece of refractory material perforated by a bore extending from the mottom of said well to the bottom of said piece, and having a cross-section at the bottom of said well of substantially equal axes, and a cross-section at the lower end of said piece of unequal axes whereby it is of elongated shape, the said bore tapering from one of said orifices to the other.

'7. A nozzle for pouring molten metal, comprising a piece of refractory material perforated longitudinally to form a bore, having a depression of substantially conical shape in its upper part, forming a well terminating in a substantially circular entrance orifice for said bore, said bore terminating in a substantially elliptical exit orifice for said nozzle, said piece of refractory having a substantial cylindrical outer surface terminating in a tapered section at its lower end, said tapered section having a bead to orient it in a nozzle plate,

8. A nozzle for pouring molten metal, comprising a piece of refractory material perforated longitudinally to form a bore, and having a depression of substantially conical shape in its upper part forming a well terminating in a substantially circular entrance orifice for said bore, said bore terminating in a substantially elliptical exit orifice for said nozzle, said piece of refractory having a substantially cylindrical outer surface terminating in a tapered section at its lower end, said tapered section having a bead to orient it in a nozzle plate, the area of said orifices being substantially equal.

9. An ingot-casting ladle comprising a bottom pouring nozzle following a substantially straight downward course, said nozzle having its inlet cross section with every two dimensions at right angles to each other substantially equal and its outlet cross section with one dimension substantially greater than the greatest dimension at right angles thereto.

10. In combination, an ingot mold and a ladle comprising a bottom pouring nozzle following a substantially straight downward course and discharging into the top of the mold, the outlet cross section of said nozzle and the transverse cross section of said mold each having one dimension substantially greater than the greatest dimension at right angles thereto, said nozzle and said mold being arranged with said greater dimensions substantially in a common vertical plane.

11. In combination, an ingot mold and a ladle comprising a bottom pouring nozzle following a substantially straight downward course and discharging into the top of said mold, the inlet cross section of said nozzle having every two dimensions at right angles to each other substantially equal, and the outlet cross section of said nozzle and the transverse cross section of said mold each having one dimension substantially greater than the greatest dimension at right angles thereto, said nozzle and said mold being arranged with said greater dimensions substantially in a common vertical plane.

LEO F. REINAR'TZ. CHARLES R. FON DERSMITH.

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