US662019A - Melting-furnace. - Google Patents

Description

No. 662,0l9. Patented Nov. 20, I900.

A. FIAT.

MELTING FURNACE.

(Applicatinn filed Nov. 80, 1898A min (No Model) lllll'l l I IIIIHII mm L Unrrnn TATns ATENT FFICE.

ALBERT PIAT, or PARIS, FRANCE.

MELTlNG-FURNACE.

SPECIFICATION forming part of Letters Patent No. 662,019, dated November 20, 1900,.

Application filed November 30, 1898. Serial No.697,881. (No model To ctZZ whom zit may concern:

Be it known that I, ALBERT PIAT, of the city of Paris, in the Republic of France, have invented a new Melting-Furnace, which is fully set forth in the following specification.

This patent relates to a new and improved furnace designed for melting with rapidity and economy metals and also ores, if necessary, in such a manner as to enable the said furnace to be constructed and the repairs thereof to be made under easy and economical conditions.

To enable the nature of my improved furnace (which is capable of operating as a eupola-crucible) to be clearly understood, reference is made hereinafter to the two sheets of drawings, illustrating the said furnace in various views and sections.

Figure l is a vertical section on the axis of a furnace on the line 1 2 and on the line 1 2' 3, Fig. 2, and showing the fireplace. Fig. 2 is a horizontal section on the line 10 11, Fig. l, and a view in plan of the fuel-distributer. Fig. 3 is an elevation, on a smaller scale, of the furnace combined with an adjacent column, so as to allow of separating and of operating the separate principal parts, as will be hereinafter described. Fig. 4 is a view in plan of the general arrangement shown in Fig. 3. Fig. 5 is a horizontal section, on a larger scale, of the operating-coluinn for moving the various parts of the furnace. Fig. 6 is an elevation in section on the line 12 13, Fig. 7, partly broken away, showing the block by means of which the tapping is effected, showing also the plug which serves to open and close the tap-hole m. Fig. 7 is a plan of the jointed plug. Fig. 8 is a horizontal section of the furnace on the line 4 5 of Fig. 1. Fig. 9 is a horizontal section taken immediately above the grate and its foundation. Fig. 10 is a section on the line 6 7 of Fig. 2. Fig. 11 is a section on the line 8 9 of Fig. 10. Fig. 12 is a vertical section on the line T V of Fig. 14 of a modification of the device for feeding and distributing the fuel to the fireplace. Fig. 13 is a section on the line N O of Fig. 12. Fig. 14 is a section on the line P Q of Fig. 13 and L M of Fig. 12.

In furnaces of all forms which have formed the subject of my previous patents the object has been to obtain (and this object has been attained) the realization of considerable economy both from the point of View of the time employed for melting a certain quantity of metal as also from the point of view of the fuel which it has been necessary to burn to efiect said melting. In this mannerIhave succeeded in melting one hundred kilos of bronze (this metal being taken as a type) in half an hour with thirteen to fifteen per cent. of coke. The quality of the metal was not lessened iii any way. Another difliculty has, however, still to be overcome-namely, that of the great consumption of plumbago relatively to the materials for which plumbago has hitherto been indispensable both for the manufacture of the crucible designed to contain the metal and also for the manufacture of the part known as the extension. The apparatus hereinafter described has for its object, among other advantages, to allow of dispensing completely with the crucibles and with extensions made with this expensive materialplumbag0especially when the furnaces have certain dimensions and are of a certain importance. This dispensing effects a considerable economy and also allows of a more practical use of the furnaces, especially for persons who inhabit distant countries, where it is not easy to procure articles made of plumbago, which are not only expensive, but also are very liable to be broken during transport. It is almost always easy in all countries to obtain articles made of refractory earth, which, if said articles are of special forms, may be easily molded.

In the construction of the new furnace the arrangement indicated in my former patents may be preservedthat is to say, the portability, the oscillation, and the tapping obtained by pouring the metal from the tap and with the aid of a beak attached to the beak of the crucible by means of a gutter or channel. These means are known and need not be described anew in the specification, in which it is more advisable to show and describe specially the new forms and arrangements which have been given to the new furnace and which offer, in addition to the economy of time and fuel already realized by my former furnaces, the other and following ad vantages hereinafter stated:

First. The possibility of doing away with the crucibles proper and of replacing them by a receiver constructed of refractory earth of dimensions varying according to the size of the furnaces, the materials employed being very economical and the articles made with said materials being highly resistant to heat and wear and tear and being capable of being readily made good or relined.

Second. Facility of obtaining the melted metal, of being able to tap, as is done in enpolas designed for melting cast-iron, and of running off from the lower part of the furnace a metal free from flowing slag.

Third. The possibility in the case of alloys of brass of stopping the tap-hole by means of a plug of pure metal or lined with refractory earth, said plug being either entirely independent of the furnace or being pivoted on a center fixed on the furnace itself.

Fourth. The facility of continuously feeding the fireplace with fuel, while avoiding all danger of burning, and of introducing cold air, although the feeding of the fuel is effected laterally while the blast is on. The coke being charged into the fireplace in any desired small quantities becomes ignited gradually and does not cool the incandescent mass.

Fifth. The possibility of melting solely by the direct action of the heat of the flame the cast iron and steel without any contact of the metal to be melted with the fuel, which may be more or less pure.

Sixth. The possibility of being able to employ not exclusively coke, but other fuels,

such as certain kinds of coal, wood, and liquid hydrocarbons.

Seventh. The facility of cleaning the grate by inclining the bars of the same, the said i11- clination being also made in order to obtain a better distribution of the fuel.

Eighth. The mosteconomical utilization of the fuel employed, which is burned under the best conditions.

Ninth. Obtaining a much longer life of the fittings or linings, even when they are made solely of refractory earth, because they are not in contact with coke except only at points situated exclusively above the fireplace and where the parts may be made of pure silica. The main advantages of the new furnace being thus set forth, I shall now proceed to describe all the separate parts, with reference to the characters on the annexed drawings.

A is the fireplace proper, of round, square,

- or polygonal shape and constructed of refractory bricks. The grate at of the same is inclined in order to effect a good distribution of the fuel, which arrives with a certain speed produced by gravity by the inclined duct 13.

a is an opening extending the width of the furnace for the purpose of facilitating the cleaning of the grate from below.

The furnace is terminated at its upper part by an arched part, in which are formed the central aperture C and the apertures c c. The aperture G serves as a passage for the ignited products of combustion, which impinge against the end part D of the crucible D and then pass through the aperture 0, so as to rejoin in the passages c the gases that rise up therethrough c and lick the outside of the crucible. The space E, which is comprised between the crucible and the lining of the furnace, is reduced to a minimum, and into this space there extend projections d d, Fig. 8, which serve as baffles to retard the ascending gases.

The above-mentioned duct B is lined internally with any suitable refractory material I), such as ganister or the like, and is provided with a sliding door I), made of similar material. The hopper part b of duct- 13 receives a quantity of fuel which it is desired to be introduced at one time into the furnace. This system of distributing fuel may be replaced by another system working in a con-' tinuous manner, the feed being effected by means of an Archimedean screw m such as that shown in Figs. 12, 13, and 14-the working of which will be easily understood. The crucible D may be made wholly of plumbago and in one piece, orit may, as shown, be composed of circular elements of refractory materials fitted together by means of tongues, or it may be made of said refractory materials,such as ganister or the like, in one single rammed piece. These elements in the form of rings have lugs d, which project into the space E and which have an outer diameter equal to the internal diameter of the furnace. These lugs are arranged so as to break joints-that is to say, the projections on one element overhanging the spaces between the projections on the element beneath-thereby forming bafiies for the products of combustion and for retarding their escape. Further, these said lugs d aid in preventing any possible bu rsting of the crucibles. The first element D is a special form and constitutes the bottom of the crucible D. It has a projection CZ", Figs. 6 and 7, in which is formed the hole through which the melted metal is drawn off. This element, which is the part of the crucible which is most exposed, may be made of plumbago, while the upper elements of the crucible may be made simply of refractory earth. Flames after having passed up through the apertures C and c" and having enveloped the crucible D pass then through the space F between the crucible B and extension H. In this manner the gases not only heat the crucible D, but also, and especially, they aid in melting the metal which is situated therein at the C0111- mencement of the operation and which is placed upon a few pieces of coke that lie in the bottom of the crucible. The previous lining of the bottom of the crucible with a little coke may be effected either by making the aperture G of sufficient diameter for introducing the same, or if said aperture is of smaller diameter then the operation is effected by lifting and turning away the upper part of the furnace by the means hereinafter described. The flames while circulating between the top of the crucible D and the bottom of the extension H may also rise through the passages G G, which are provided to the number of four or six or more, and the said flames thus heat and melt before direct action the metal which is placed during the operation into the said extension H, said extension being constructed of several parts or in one single piece of refractory earth and being arranged directly above and in the axis of the furnace the walls of which are contin ued above those of the said extension, and thus constitute a sort of furnace, which may be called a cupola-crucible. As shown in Fig. 1, extension H is composed of parts 71 h, separated by blocks it, between which latter are formed openings through which the flames enter the interior of the extension. Part h also has openings 72 therethrough communicating with the passages GT. A light cover Z of refractory earth closes the whole, while allowing any flames in excess to escape in such a manner that it retards them only so as to produce a slight pressure of the gases inside the furnace. There is thus elfected by this kind of cascade or baffle, first, an intense heating of the crucible D by the flame, which is able to reach its contents; second, the direct action exerted by said flames by reason of their introduction through the holes or the zone F and the passages G G in the extension H and contact with the material contained therein; third and finally, there is the action of the saidflames also upon the metal piled in the extension passage or mouth R in such a manner as to aid to fuse the same by means of the extension H. Thus there is effected the best utilization of the heat contained in these flames, while avoiding all contact with the fuel.

I, Fig. 6, is the plug which is pivoted at J and which serves (in case of melting bronze) especially for closing the outlet-orifice for the metal. Any other arrangement may be employed so long as the fou ndryman is protected from jets of melted metal.

K, Fig. 1, is an aperture formed in the top of the crucible B and connected through a small passage to the exterior of the furnace in such a manner as to allow the floating slag to flow out. This aperture is stopped externally by means of a plug of refractory earth during the working of the furnace. It is unstopped in order to give issue to the flames when it is desired to heat the metal after having removed the extension and covered the crucible.

Z Z are spy-holes which allow of observing the behavior of the fuel on the grate and of stokingit for the purpose of spreading it out if necessary.

The new crucible-furnace in the form of a cupola being thus described, I shall now proceed to describe its mode of operation, or rather the process for producing a melting,

or the melting, becausethe said melt may be continued.

A sufficient charge of coke is placed upon the grate, and also a few pieces of cokeare placed in the bottomof the crucible D. Then the metal to be melted is placed on top of this sinall quantity of coke and in the extension as much as it can hold. The blast is then turned on, gently at first and then more powerfully, and before any coke commences to sink on the grate successive small charges of coke are fed in. As the metal descends in the crucible more metal is placed in the extension unless the desired quantity has been able to be placed at one time for a melt. Cleaning is effected When necessary in order to remove the slag and to leave the whole of the useful space for the melted metal, and when the fusion is completely effected the running-out hole is unstopped and the desired quantity of metal is drawn off, the procedure being exactly the same as with an ordinary cupola, for which it may be used as a substitute for melting small quantities of ore or metal.

The furnace might be erected and charged and operated in the manner above described; but it is necessary to make allowances for the wear and tear of refractory material and for the necessary repairs. In order to facilitate the construction of the furnace, its erection, and the repairs which become necessary from time to time, the apparatus has been divided into four distinct parts, each inclosed in a sheet-metal casing of the same diameter fiting in a common uniting-ring and consisting, first, of the part X, which incloses the grate and the furnace; second, of the part Y, which carries the feeding apparatus; third, of the partZ, which carries the crucible, and, fourth,

of the part WV, which carries the extension. In 7 each of the casings of these parts and on the same side there is provided a projecting part 'm, in which is formed an opening. (See Fig.

Near the furnace and on the side where it is least inconvenient there is arranged a small column N, cast hollow, in which there is formed a longitudinal slot n. A screw V carries three nuts i each having an arm 1; thereon projecting through slot at and supporting a ring V V V, respectively, movable on the column N. Screw V may be rotated by hand-wheel 0. Three supports S S S engage about and are fitted to move with slight friction upon the said column above the rings V V" V, respectively. These supports carry pins M, which fit into the openings in projections m, and the nuts V, which move them, are adjusted in such a manner as regards their position as to height on the screw V that on beginning to turn the hand-wheel 0 first the part which contains the extension to is raised a few centimeters, which allows of turning this said first part to the extent desired. Then on continuing to turn the hand-wheel the part Z, which contains the crucible, is raised, and then the part Y, which contains the fuel'feeding device, in such a manner that each part is thus separated from the others for the purpose of effooting repairs or for the complete reconstruction of the furnace. It will be readily understood that it is sufificient to actuate the column by means of the central screw in the opposite way in order to replace all the parts mentioned without delay.

I claim- 1. In a smelting-furnace, the combination with a fire place or chamber, of a cruciblechamber located above said fire-chamber, passages connecting the fire-chamber with the crucible-chamber, and a crucible located entirely within the crucible-chamber, said crucible being formed with projections on its outer face which. fit closely the walls of the crucible-chamber and are so arranged that the projections above overhang the spaces between the projections below whereby said projections act as battles to cause the flames to take a zigzag course in ascending about the crucible.

2. In a melting-furnace, the combination with a fire place or chamber, of a cruciblechamber located above and in comm unication with the fire-chamber, a crucible located ontirely within said crucible chamber and formed of a plurality of superimposed hollow sections, each made in one piece of refractory material and which sections have projections on their outer faces which fit closely the walls of the crucible-chamber.

3. In a melting-furnace, the combination with a fire place or chamber, of a cruciblechamber located above and in com munication with the fire-chamber, a crucible located entirely within said crucible chamber and formed of a plurality of superimposed hollow sections, each made in one piece of refractory material and which sections have projections on their outer faces which fit closely the walls of the crucible-chamber and are so arranged that the projections on the upper sections overhang the spaces between the projections on the lower sections thereby acting as baffles to the flames arising around the crucible.

4. In a melting-furnace, the combination with a fire place or chamber, of a cruciblechamber located above and in comm unication with the fireplace, a crucible in said cruciblechamber, said crucible being formed of a lower cup-shaped section having a spout projecting therefrom through the side Wall of the furnace, a number of superimposed hollow sections above said cup-shaped section, each of said hollow sections being formed in one piece, and projections on said sections fitting closely within the crucible-chamber.

5. The combination with a smelting-furnace composed of a plurality of superimposed separable parts or sections, of a column located in proximity to thefurnace,supports or brackets connected at their outer ends to the several upper sections of the furnace respectively and free to swing about said column as a pivot, and means for elevating said supports and sections in succession.

6. The combination with asmelting-furnace composed of a plurality of superimposed separable parts or sections, of a column located in proximity to the furnace,supports or brackets connected at their outer ends to the several upper sections of the furnace respectively and free to swing about said column as a pivot, a vertical slot in one side of the colnmn,a screw vertically disposed in the coin mn,nuts on said screw each having an arm thereon projecting through the slot in the column, and rings or collars about and free to slide on the column, said collars being located one above the projecting end of each arm and beneath each support.

7. The combination of a smelting-furnace, comprising four superimposed separable sections, namely, a fixed part consisting of the grate and fire-chamber, the next section embracing the top wall of the fire-chamber and the fuel feeding or distributing device, the third portion embracing the crucible, and finally the topmost section containing the extension, the three upper sections being movable, of a column located in close proximity to the furnace, and means on said column for elevating the three upper sections and independently swinging the same about the column as a pivot.

In testimony whereof I have signed this specification in the presence of two subscribing witnesses.

ALBERT PIAT.

Witnesses:

EDWARD P. MAoLEAN, EDWARD BEUGNIOT.

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