US2193365A

US2193365A - Pouring nozzle

Info

Publication number: US2193365A
Application number: US189801A
Authority: US
Inventors: Cantoni Rene
Original assignee: Individual
Current assignee: Societe dElectro Chimie dElectro Metallurgie et des Acieries Electriques Dugine SA SECEMAU
Priority date: 1937-03-31
Filing date: 1938-02-10
Publication date: 1940-03-12
Anticipated expiration: 1957-03-12

Description

March 12, 1940. (:ANTONl 2,193,365

POURING NOZZLE Filed Feb. 10, 1938 I'NVENTOR Rene Can-l oni Patented Mar. 12, 1940 POUBJNG'NOZZLE Rene Cantoni, Uglne, France, assignor to Socit dElectrochimie, dElectromtallnrgle et des Acieries Electriques dUgine, Paris, France, a

corporation of France Application February 10,1938. Serial No. 189,801

. 1 In France March 31, 1937 1 claim. (or. cast) The cooling of a fused m'etal while it is flowing by gravity from a receptacle, furnace or ladle through a pouring orifice formed by a nozzle, and

the variation of the height of the metal above this orifice, give rise to variations in the conditions of casting in an unfavourable manner and often give rise to surface or internal defects of the cast ingots or pieces.

To avoid these'disadvantages the section of the pouring nozzle placed in the pouring orifice has been varied, during the course itself of the casting.

The processes most utilized consist either in constituting the nozzle of a material which is attacked by the metal during and in proportion to the casting which ensures an automatically increasing flow section, or in adjoining to the normal nozzle an. auxiliary nozzle .of smaller section which can be taken off during the pouring or replaced by another nozzle having a greater section. f

The first process has the defect of not being regulatable. The difficulty will in fact be understood which there is in defining the composition and the physical state of the constituents of a nozzle which should be corroded in a regular way by .the metal. Moreover, this process assumes that the temperature of-the metal remains constant from one casting to, another. When in fact it is otherwise, the nozzle which is more attached 'by hot metal than by a cold metal enlarges more quickly the hotter the metal a result .which is the converse of that which is required. Now in practice the castings of metal have not all the same temperature, and this process, however simple it may-be, must none'the less b'e rejected. I

The Batty process abovereferredto has not these disadvantages; it. isrational and adjustable but it 4 necessitates a. mechanical device which however simple is still too complicated v during casting in a regular manner from. one

casting to another and also permitting to adapt from the beginning of the casting, the section of the nozzle to the temperature 'of the metal. Thanks to these means it is also possible, in case the casting -orifice is obturated, to instantaneously re-establish the casting.

These means consist on the one hand informing the nozzle of a refractory material possessing' a sufliciently high mechanical resistance to be able to resist the forces which a nozzle will normally have to withstand, but nevertheless .sufllciently weak so that it is possible to section; .the nozzle at desired points and on the other hand in imparting to this nozzle a variable section narrowing towards the bottom and a length such that by sectioning or breaking the nozzle and shortening it, increasing flow sections'are offered tothe metal. By sectioning the nozzle it should be understood as well a sectioning obtained .by a cutting action'as by a breaking action.

I The flow channel of the nozzle is for this-pur pose formed either of a succession of cylindrical .or substantially cylindrical parts whose sections channel narrowing towards the outlet of the nozzle. I p

Zones of lower resistance are if desired created by notches or circular grooves so as to facilitate the sectioning of the nozzle at determined points.

To utilize the nozzle according to the invention it is sectioned at the desired point to obtain thepouring orifice of desired dimensions, for example by employing a cutting member at that level of the nozzle which comprises the fiow' section which it is desired to obtain.

The process and the apparatus are as seen very-simple; .no mechanical device is necessary. In practice within the limit of dimensions of the nozzle the flow section may be regulated as desired; The shortening may take place in one or several stages according as to whether one has use of one or more than two sections. One may thus compensate readily and regularly the variations of temperature and pressure which are exhibited during the same cast, this being done by shortening the nozzle by the quantity which corresponds to the new section necessary at the considered moment. The variations of temperature of the metal from one cast to another can also be compensated in use forsuch castingsmade under variable initial conditions of temperature. identical nozzles which have been previously cut at dilferent lengths corresponding each to the saidtemperature. By means of such a nozzle it is also possible to: reestablish the outflow of the I In any case, the operation of modification of sections takes place in a few seconds. i

The invention is illustrated in the accompanying drawing, in which Figures 1-4 are in their left halves diametrical sections and in their right halves outside elevations of four diflerent forms of nozzle; Figure 5 shows on a smaller scale a pair of shears for sectioning the nozzle.

In the form of construction of Figure 1, the nozzle comprises in the ordinary way a head I extended by a limb .2 but instead of this limb being short as is ordinarily the case it is extended to 3 and its interior channel 4 diminishes in section from above to below. By sectioning the limb of the nozzle for example along the planes A-B, 3-3, the minimum section oflered to the passage of the metal is varied by creating besides the initial section s1 larger sections such as s2, ea.

In Figure 2 is shown a similar nozzle but which comprises grooves 5, 6, I facilitating sectioning corresponding with predetermined pouring sections s2, s3, $4.

In the embodiment of Figure 3, the limb 2 of the nozzle is represented shorter than in Figures 1 and 2. The channel 4 of section 82 comprises a narrowed portion 8 of section s1. Above this section 31 the limb 2 of the nozzle is notched by a circular groove 9. By cutting off the nozzle at the height of this groove the flow section passes from s1 to .92.

In Figure 4 which corresponds to a nozzle of the same kind as that of Figure 3, the limb 2 of the nozzle is more elongated and there are two constrictions Ill and H in the flow channel and two grooves l2 and I3. The casting being commenced with the section's1, the nozzle is afterwards cut during the casting, at I! to obtain the section 82 and then at l3 to obtain the section ss.

Instead of grooves one may-provide notches for starting breaking such as those shown at a and b of Figure 1. Wherever the word groove is used in the present specification and in the appended claim a notch is meant as well.

To produce sectioning there will be used for example a pair of shears such as that shown in Figure 5, comprising two handle members I4 and I5, pivoted at I6 and two blades l1 and I8 with which the limb of the nozzle will be cut at the desired level.

In the case of a nozzle of the type of Figure 3, one may simply break the lower part of the limb by a blow with an iron bar, given below the groove 9.

With the object of avoiding any disturbance in pouring as a consequence of an accidental cracking produced in the body of the nozzle, the rings, such as I 9, which bound the grooves, may advantageously be provided with a collar.

As material for the formation of the nozzle there may be utilised in particular that called graphite in commerce and which is formed of a mixture of carbon and clay.

In the appended claim when reference is made to a channel, successive sections of which increase from the outlet to the inlet, it should be understood that such an expression designates not only sections successively and regularly increasing so as to confer to the channel a frusto conical or substantially frusto-conical shape, but

also sections increasing in the shape of successive Zcylindrical or substantially cylindrical portions,

as hereabove described in relation with Figures 1 to 4.

\It should be also understood that when reference is made to a nozzle having a section of less resistance, that such an expression designates a nozzle provided with one section of less resistance or with a plurality of such sections. In particular, in the case of a nozzle in which the channel is formed of successive cylindrical portions of increasing transverse areas from the outlet to the inlet, the said piece may have a plurality of such cylindrical sections. It should also be understood that the said section of less resistance may be constituted by any suitable means and in particular by means of an outer groove.

It should be lastly understoodthat when reference is made to shortening a channel during the casting of the metal, that this operation can be made once, or if necessary, several times during the one and the same casting.

What I claim is:

A nozzle for casting molten metal from a receptacle, comprising a single unitary refractory structure including a head adapted to fit within the receptacle and an extension extending a considerable distance below the receptacle, said extension provided with a longitudinal flow channel successive cross sections of which increase from the outlet to the inlet thereof, said extension having a weakening groove or notch at at least one point of its length corresponding to an increased channel cross section as compared 'with the channel cross sectiomat its outlet, whereby the extension may be readily broken at said weakening groove or notch to provide an increased flow of molten metal.

RENE CANTONI.