US402782A

US402782A - Open-hearth melting-furnace

Info

Publication number: US402782A
Authority: US
Publication date: 1889-05-07
Anticipated expiration: 1906-05-07

Description

(No Model.)

4 SheetsSheet 2. W. SWINDELL. OPEN HEARTH MELTING FURNACE.

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mm mm MWWM N, PETERS Pho plitlmgqpl-er, Washington, ac,

(No Model.) 4 Sheets-Sheet 3.

W. SWINDELL. OPEN HEARTH MELTING FURNACE,

Patented May 7, 1889.

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(No Model.) 4 Sheets-Sheet 4. W. SWINDELL. OPEN HEARTH MELTING FURNACE.

No. 402,782. 7 Patented May 7, 1889.

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11467401 I II V Atty.

UNITED STATES PATENT OFFICE.

WILLIAM SWINDELL, OF ALLEGHENY, PENNSYLVANIA.

OPEN-HEARTH MELTlNG-FURNACE.

SPECIFICATION forming part of Letters Patent No. 402,782, dated May 7, 1889. Application filed July '7, 1887. Serial No. 243,696- (No model.)

To all whom it may concern;

Be it known that I, WILLIAM SWINDELL, residing at Allegheny, in the county of Allegheny and State of Pennsylvania, a citizen of the United States, have invented or discovered certain new and useful Improvements in Open-Hearth Melting-Furnaces, of which improvements the following is a specification.

The invention described herein relates to certain improvements in gas furnaces for melting metals, and has for its object a construction of furnace wherein the metal may be held in a molten condition as long as desired away from or outside of the oxidizing influence of the fusing-flame.

Theinvention consists, in general terms, in the construction and arrangement of parts, substantially as hereinafter more fully described and claimed.

In the accompanying drawings, forming a part of this specification, Figure 1 is a top plan View of the furnace. Fig. 2 is a sectional elevation of the same on the line 0/; 0:, Fig. 1. Fig. 3 is a horizontal section on the line y y, Fig. 2. Fig. 4 is a view similar to Fig. 2 on the line z 2, Fig. 3.

In the practice'of my invention regenerative chambers l and 1, filled with checkerwork, are constructed in the usual manner, each regenerative chamber being provided with

lines

2 and 2, leading from the lower end of the chambers and connecting a short distance from the chambers With a flue, 3, leading to the stack 4. (See Figs. 2 and 3.) On suitable piers, 5, on the regenerative chambers is built the circular or approximately circular hearth 6, provided. with an extension, 7, on one side, and with chargingdoors 8 at suitable points around its circumference. The floor of the hearth is made to incline from the rear and sides toward the extension 7 in which the crucible 9, for the reception of the molten metal, is formed. In the end of the extension is formed the tap hole 10, connecting with the crucible at its lowest point, in order that all the metal. may be drawn therefrom.

Outside of the tap-hole is secured a spout or trough,11, for conducting the metal to a ladle or other receptacle.

In the bottom of the extension, immediately under the crucible, is located a door, 12, normally held in a closed position by a bar, 13, or any suitable latch, the purpose of said door being to permit of the discharge of slag, scoria, or other foreign material in the inanner customary in the ordinary cupola-furnace.

From the upper ends of the regenerative chambers flues 14 and 14 extend, first horizontally, then vertically, and then back horizontally, into the hearth on each side of the extension 7, as shown in Figs. 1 and 3, said flues entering nearly tangentially with the inner wall of the hearth. Gas-

pipes

15 and 15 are inserted through the outer walls of the fines 14 and 14 at a point nearly opposite the entrance of said lines into the hearth, in order that the gas and air passing along the flues 14 and 14 may be thoroughly min gled before entering the hearth. v

Openings

16 and 16 are formed in the

flues

2 and 2, (see Fig. 3,) for the admission of air into the regenerative chambers through said On each side of these

openings

16 and 16 are arranged rails or bars 17, on which are mounted wheels 18, carrying the ,valveplate 19, adapted to alternately :cover the openings. A chain, 20, connected to each side of the valve-plate 19 and passing around the guide-pulleys 21, is attached to a valveplate, 22, suspended from wheels 23, mounted on bars 24 in such manner as to move transversely of the

fines

2 and 2 and close one or the other of said flues at a point between the

openings

16 and 16 and the junction of the flues with the main flue The valve-

plates

19 and 22 are so arranged and connected by the chain 20 that when the valve-plate 19 is over the opening 16 the valve-plate 22 will close the flue 2 as against connection with the fine 3, and vice versa. This construction and arrangement of valves permit of the reversal of the operation of the furnace by the single movement of a lever.

In order to prevent dirt and other foreign material from entering and clogging up the regenerative chambers, I provide pockets 27 at the lower ends of the vertical portions of the fines 14 and 14. [00

In order to heat the regenerative chambers or to maintain heat therein while the hearth is being repaired or a fresh charge of ma terial is being placed therein, 1

arrc nge valves

24 and 24 in the fines 14 and 14 at a point near their entrance into the hearth, for the purpose of closing connection between said flues and the hearth. \Vhen it is desired to heat the regenerative chambers without heating the hearth the

valves

24 and 24 are closed and one or the other of the

fines

2 and 2 opened. The gas being ignited in the fine 14 or 14 corresponding to the open flue leading to the stack, the flame will be drawn down through the regenerative chamber, air for supporting the combustion of the gas be ing admitted through openings 25 and 25 formed in the fines 14 and 14 at points above the entrance of the gas-pipes, (see Fig. 4,) said openings being closed during the normal operation of the furnace by

doors

26 and 26", as shown. If it is desired to heat both chambers simultaneously, the

valves

19 and 22 are placed at a point midway of their movement, thus partially opening both

lines

2 and 2, the

openings

16 and 16 being temporarily covered by a plate or other suitable means.

It will be observed that by reason of the angle at which the fines 14 and l4 enter the heart-l1 the flame will pass around the hearth near the wall thereof, and the molten metal in the crucible will not be subjected to the direct action of the flame, and hence can be held there for any desired. length of time without excessive oxidation.

One of the prominent characteristics of the invention herein described is the provision made for the retention of the metal in a molten condition without subjecting it to the direct action of or contact with the flame, and thereby avoiding all oxidation of the metal; hence the shape or contour of the hearth may be changed from a true circular form, as shown, to a form more or less oval in horizontal section, or to any other form, provided the inletflues for the gas and air be so arranged that the products of combustion will. not pass di rectly over or in immediate contact with the molten metal.

Cupola-furnaces having the crucibles or receptacles arranged below the tuyeres, and therefore out of. the line of flow of the fusingflame, are old and well known, as are also furnaces having a receptacle for the reception of the molten metal independent or outside of the melting-hearth, but still in the line of How of the fusing-flame. No claim is therefore made herein to such construction, my invention being principally applicable to that class or kind of melting-furnaces employing a natural draft, and known in the art as airfurnaces with or without regenerative chambers.

I claim herein as my invention- 1. An air-furnace for melting metal. having, in combination therewith, a crucible for the reception of molten metal located out of the line of flow of the fusing-flame, and combined gas and air flues entering said furnace in each side of the crucible, substantially as set forth.

2. The combination, in an air-furnace for melting metal, of a circular melting-hearth, a crucible for the reception of molten metal located at one side of the center of the hearth, and combined gas and air fiues entering the hearth on each side of the crucible and in a line approximately tangential to the wall of the hearth, substantially as set forth.

3. The combination, in an air-furnace for melting metal, of a circular melting-hearth provided with a lateral extension containing the crucible for the reception of molten metal, and combined gas and air flues entering the hearth 011 each side of said extension andv in a line approximately tangential to the wall of the hearth, substantially as set forth.

4. The combination, in an air-furnace for melting metal, of a circular melting-hearth, a lateral extension from said heart-h containing the crucible for the reception of molten metal, and a door located in the bottom of said extension under the crucible,substantially as set forth.

I11 testimony whereof I have hereunto set my hand.

/VILLIAM SVVINDELL. Witnesses:

DARWIN S. WoLoorrr, XVILLIAM' REAL.