US2047949A - Tuyere construction for cupolas - Google Patents

Description

July 21, 1936. .1. K. CLUTTS E CONSTRUCTION FOR CUPOLAS TUYER 1935 3 Sheets-Sheet 1 Filed Aug. 5

INVENTOR JOSHUA K.CLUTTS g ATTORNEY July 21, 1936. 'K, CLUTTS 2,047,949

TUYE'RE CONSTRUCTION FOR CUPOLAS Filed Aug 5, 1935 3 Sheets-Sheet s FIG.5.

FIGYL INVENTOR JOSHUA K.CLUTTS A TTORNEY Patented July 21, 1936 UNITED STATES PATENT OFFICE 2,041,941; roman cous'rnuc'nou ron CUPOLAS Joshua K. Clutts, Detroit, Mich. Application August 5, 1935, Serial No. 34,656

Y 11 claim. (01.266-41) pensation for such variation has, to some extent,

been achieved by pressure control of the blast delivered to or from the tuyeres, as by varying the blower speed, or changing the size of the tuyere passages. Such compensation, however,

has been far from complete, since for a tuyere zone of fixed diameter, proper penetration of the load by the blast prohibits other than a limited reduction of the blast pressure, and increase of the blast pressure can be eiiected to only a quite limited extent without detriment to the quality of the melt.

An object of the invention is to provide for varying the blast capacity of cupola tuveres to suit varying requirements in the rate of melting, and for coincidently varying the tuyere length so that proper penetration of the load by the blast will be assured.

Another object is to form a cupola tuyere in sections, whereof a suitable number may be used 30 to extend the tuyere a desired distance toward the cupola axis, said sections predeterminedly varying in air delivery capacity, so as to reduce the volume of the blast proportionately to the inward extent of the tuyeres.

35 A further object is to provide a set of nozzles, differing in capacity, and each corresponding to one of said tuyere sections, the innermost tuyre section, in any installation being adapted to receive the nozzle corresponding to such section,

to predeterminedly restrict the delivered blast proportionately to tuyere length.

A still further object is to provide for reducing the volume of air delivered by a tuyere by employing one or more inserts in the working nozzle 45 to reduce the air capacity of the tuyere.

These and various other objects the invention attains by the construction hereinafter described and illustrated in the accompanying drawings,

- wherein:

Fig. 1 is an axial sectional view of thetuyere zone of a cupola having its volume of delivered air reduced in accordance with the invention.

Fig. 2 is a horizontal sectional view of the improved construction as adapted to a lower tuyere 55 of a cupola.

to the cupola axis (not shown).

Fig. 3 is a vertical sectional view of the same, taken on the line 3-3 of Fig. 2.

Fig. 4 is a cross sectional view of the same, taken upon the line 4-4 of Fig. 3.

Fig. 5 is a horizontal sectional view of the im- 5 proved construction, as applied to an upper cupola tuyere.

Fig. 6 is a longitudinal vertical sectional view of the same, taken upon the line 6-6 of Fig. 5.

Fig. 7 is a cross sectional view of the same, 10 taken upon the line '|-'I of Fig. 6.

Fig. 8 is a perspective view, showing complete sets of upper and lower tuyere nozzles.

In these views the reference character I designates the usual cylindrical steel shell of a cupola, 5 2, a fire brick lining applied interiorly to said shell, and 3, the usual wind box exteriorly ena ing the shell.

It is usual to extend through a cupola wall a lower circular series of relatively large tuyeres 4, and an upper circular series of smaller tuyeres 5. In the illustrated installation, each lower tuyere comprises several open-ended, box-like sections.

of which four are shown, and designated respectively 6, I, 8, and 9. These sections are adjoined in substantially end to end relation and jointly form an air passage through the lining. The opposite side walls of the several sections are correspondingly convergent and preferably radial The height of the sections 6, I, 8, and 9 is successively reduced in the order enumerated, and this successive reduction, together with the convergency of their side walls, serves to considerably reduce the cross sectional area of the tuyere, as it extends inwardly.

While the tuyere is illustrated as comprising four of the described sections, it is to be understood that a lesser or greater number of sections may be employed according to the desired reduction of the blast volume.

Within the innermost section of the tuyere, there may be installed an open-ended box-like nozzle l0 predeterminedly limiting the discharging blast, and preferably such nozzleextends beyond the tuyere proper, terminating flush with the inner face of the thickened lining. To facilitate removal or replacement of such nozzle, it is preferred to space it downwardly from the top of the innermost tuyere section and to seal such space with brick or clay or mortar or the like as indicated at ll. Thus molten metal or slag is prevented from looking the nozzle in position, since upon removal of the sealing material, the

nozzle can be readily freed by prying it upward with a crow bar or the like.

A tuyere stock 82, arranged exteriorly of the cupola, serves to deliver air from the wind box 3 through the shell I to the tuyere section 6, it being understood, however, that such tuyere stocks are rendered superfluous when the wind box directly surrounds the tuyere zone, as is a common construction.

Each upper tuyre comprises a set of box-like, open-ended sections i3, it, i5, and i6, adjoined in an end to end relation to jointly form an air passage through the cupola lining. Within the inner section and removably resting on its bottom, is a box-like open-ended nozzle ill. The outermost tuyere section is preferably formed I adjacent to the shell l with an upward extension ing the blast'when its corresponding tuyre section is innermost. Preferably the sections of both the upper and lower tuyeres have an interfitting relation adapting them to be readily established in a proper end to end relation. Thus, each section (excepting the outermost) of each tuyere may be formed upon its side walls with a pair of lugs I9 projectingto engage at each side of the outwardly adjacent tuyre section, maintaining accurate alignment.

If it is desired to reduce the tuyere capacities further than is effected by the nozzles l0 and I1, this may be done, as illustrated by inserting in each nozzle a metal plate 20 (or a number thereof) said plates resting freely on the bottom mem bers of the nozzle.

Preferably each tuyre stock l2 will have, in its lower portion an opening normally closed by a door 2!, through which opening, the corresponding nozzle l0 may be removed, if desired, while the cupola is in operation. Such a provision is desirable in case any nozzle l0 becomes so clogged, during operation, with slag or metal, as to require cleaning or replacement.

The construction, as described and illustrated adapts a cupola for considerable variation'of its blast volume without sacrifice of efficiency. If the interior tuyere zone diameter of the illustrated cupola is originally inches, and it is desired to decrease this to 54 inches, such decrease may be eflectedby addition of another tier of brick to the lining, and of another section to each of the upper and lower tuyeres. By adding another layer of brick and another set of tuyere sections, the interior diameter of the tuyere zone ,may be further decreased to 44 inches and a still mum of efilciency and fuel economy. 'The figures herein given for the various tuyere zone diameters merely illustratev the possibilities, and the tuyre sections and nozzles may be proportioned to establish such diameters as are preferred,

Removal of a nozzle ill from the inner end of the corresponding tuyere will at times be desirable. Such removal may be accomplished by shoving the nozzle back from its illustrated position so that it may be swung transversely to said position withinthe wider outer portion of the tuyere. It may then be easily withdrawn through the inner end of the tuyere.

It is essential to note that the described construction, in making provision for a reduction in 10 the hourly outputof molten metal, not only predeterminedly cuts down the blast volume but at the same time predeterminedly increases the inward extent of all the tuyres, thus providing the additional penetration of the stock that is made 15 necessary by the reduction in blast volume. Prior provisions for blast reduction have failed to effect a corresponding increase in tuyere length, and they have not adequately reduced the blast because the reduction of the tuyere passages has necessitated an increase 'of pressure to maintain penetration. Any material surplus of air, with resultant fuel waste is avoided by the present invention. 4

In addition to adapting a cupola for efiiciently delivering molten metal at selective rates, the

, scope of the following claims.

What I claim is: 1. A cupola tuyere comprising a plurality of tuyere sections adjoined in the direction of airflow to jointly form an air passage, the flow capacity of said sections being successively reduced in the direction of air flow, and one or more of the sections at the outlet end of the tuyre being removable to increase the capacity of the tuyere.

2. A cupola tuyere as set forth in claim l,-the

lateral walls of the tuyre converging in the di- I rection of air flow at substantially the same angle in all of said sections.

3. A cupola tuyere as set forth in claim 1, the

adjoined ends of said sections having an inter-'- fitting relation.

4. A cupola tuyre as set forth in claim 1, the height of said sections being succcessively reduced in the direction of air flow.

5. A cupola. tuyere as set forth in claim 1, the lateral walls of the tuyere converging in the direction of air flow at substantially the same angle in all of the sections, and the height of said sections being succcessively reduced in the direction of air flow.

' 6. In a cupola tuyere as set forth in claim 1, a nozzle inserted in the innermost section, predeterminedly limitingthe air flow, and means establishing an approximate air seal between the nozzle and innermost section.

'7. In a cupola'tuyre as set forth in claim 1,

a nozzle removably inserted in one of the tuyere sections and predeterminedly limiting the air flow through the tuyere.

8. In a tuyere construction, the combination with a set of tuyere sections differing in capacity The nozzles l0 and whereoi a seiectivenumber may be disposed in an end to end relation to form an air passage, of a corresponding set of nozzles, each insertible in the corresponding tuyere section to predeterminedly limit its capacity.

9. The combination with a tuyre having side walls and a fiat bottom, of a plate proportioned to fit between said walls on the tuyre bottom to predeterminedly reduce the capacity of the air passage formed by the tuvere.

10. The method of adapting a foundry cupola for eiiicient operation at less than its maximum melting capacity, consisting in providing the tuyeres of such cupola with inward extensions, and in so thickening the lower portion of the cupola lining as to embed said extensions in the thickened lining.

11. The method of adapting a foundry cupola. 5

the thickness of the cupola lining throughout 10 the tuyere zone, and gradually reducing such thickness upwardly from the tuyeres.

JOSHUA K. CLU'I'TS.

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