US614971A - Cooling-jacket for blast-furnaces - Google Patents

Description

No. 6l4,97|. Patented Nov. 29, I898. J. W. NESMITN.

COOLING JACKET F08 BLAST FURNACES.

(Application filed-Apr. 15, 1898.) (No Model.) 3 Sheets-Sheet L FIG. 7. H622.

WITNESS: INVENTOH A TTOBNEY m: Nonms pzrzns co. Pumaumo WASHINGTON n c No. 6l4,97l. Patented Nov. 29, I898. J. W. NESMITH.

COOLING JACKET FOB BLAST FURNACES.

(Application filed Apr 15, 1898.)

3 Sheets-Sheet 2.

(No Model.)

MM A/VW ATTORNEY N0. 614,97l. Patented Nov. 29, I898. J. W. NESMITH. COOLING JACKET FOR BLAST FURNACES.

(Application filed. Apr. 15, 1898.)

3 Shaets$heat 3.

(No Model.)

JZUGIW' THE Nanms PETERS c0. Pumouwo. wnsumsrov u c.

UNITED STATES ATENT rrrcn.

JOHN XV. NESMITH, OF DENVER, COLORADO.

COOLING-JACKET FOR BLAST-FURNACES.

SPECIFICATION forming part of Letters Patent No. 614,971, dated November 29, 1898.

Application filed April 15, 1898. Serial No. 677,680. (No model.)

To all whom it may concern:

Be it known that I, JOHN W. NESMITH, a citizen of the United States, residing at Denver, Colorado, have invented certain new and useful Improvements in Cooling-Jackets for Blast-Furnaces, of which the following is a specification.

In blast-furnaces used for smelting silverlead, copper, and other minerals and metals it is common to use metal water-jackets through which water is kept circulating in order to prevent them from being burned out. These water-jackets constitute the sides or walls of the furnace in whole or in part, and it is within a space inclosed by these water-jackets that the smelting operation goes on.

In my present invention I use air from the blower on its Way to the furnace instead of water for keeping the sections of metal jackets sufficiently cooled to prevent their destruction by the heat of the furnace, and at the same time the air is heated to some degree, and the heat thus taken up by the airblast is passed forward into the furnace and saved.

I am aware that air-cooled jackets have been used in certain of the upper zones of blast-furnaces; but so far as I am aware prior to my invention no air-jacket was ever used permanently in the lower or melting zones of a blast-furnace. The ordinary jacket with a single chamber through which to blow air cannot stand the intense heat of the smeltingzone of a blast-furnace, because in any such device a sufficient direct exposure of all the air to the whole surface of the jacket cannot be had to take up the heat with sufficient rapidity to preserve the jacket from destruction in the intensely-heated smelting-zone of the furnace. The heat of the exposed surface or fire-wall cannot be transmitted by conduction to all the air on its rapid passage through, and as the whole of the air as it passes through is not exposed to the heated surface of the jacket, however large the volume of air passing through the chamber, so little of it comes in actual contact with the heated face of the jacket down in the smelting-zone of the furnace that the jacket at once becomes dangerously hot, while the volume of air passes on into the furnace without absorbing any considerable portion of the heat of the jacket.

The object of this invention is to provide an air-jacket designed specially for the smelting-zone of the furnace, wherein every atom of the air-blast is made to impinge directly upon the heated inner surface or fire-wall of the jacket, and thus the heat by actual con tact of all the air is taken up by it and practically equalized throughout as between the metal fire-wall of the jacket and the volume of air passing through. In other words, by the direct exposure of every atom of the air in its passage to every part of the fire-wall of the jacket the air absorbs the heat from the surface of the jacket, cooling the latter to the extent that the air becomes heated until the volume of air passing and the iron of the jacket has nearly the same temperature. This distribution of the air and its contact with the heated inner surface or fire-Wall of the jacket is accomplished in an effective way by a simple device, as shown in the drawings, in which-- Figure 1 is a vertical section through the jacket on one side. Fig. 2 is an elevation of one side of a furnace, showing my system of jackets. Fig. 3 is a perspective view, partly in section, of one of the jackets. Fig. 4 shows, partly in elevation and partly in section, the invention as applied to a furnace.

The furnace shown is a rectangular cop'permatting or silver-lead smelting blast-furnace of convenient arrangement, supplied with air-cooled jackets, and in its general contour and proportions not unlike a common type of water-jacketed furnace.

The jacket-sections a of my invention are made with partitions or diaphragms c, Fig. 1, dividing them into two chambers, the one an outer chamber, into which the air-blast is blown, the other an inner chamber, into which the air passes from the outer one by many small openings suitably spaced and distributed throughout the whole area of the diaphragm, and these small openings are preferably supplied with pipes or nozzles f, extending nearly across the inner chamber and terminating at points near to the inner or fire wall k of the jacket, so that when an air-pressure is supplied from the blower into the outer chamber of the jacket it passes through the diaphragm by the small openings or pipes or nozzles and impinges with a force proportional to the blastpressure directly against the inner or fire wall 7c of the jacket, and thus is insured a constant blast of cold air impinging on the fire-wall of the jacket in many small jets throughout its whole surface.

Myinvention also includes the arrangement shown of the jacket-section b, with the conduit-girder c located above it, this conduitgirder being adapted to carry the weight of a part of the furnace and at the same time acts as a conduit through which the air-blast from the blower passes. I prefer to make the inner side of the conduit flush with the jacket 1), and the air-blast prevents it from being heated to such an extent as to endanger its integrity, and in the position shown it is best adapted to any brick walls or other superincumbent structure necessary or desirable to place upon it for the upward extension of the furnace.

In operation air from the blower enters the conduit 0, passes thence down through the single-chamber upper jacket 6, and thence by suitable connection into the back chamber of the jacket-section a, through the pipes or nozzles f, impinging against the fire-wall of these jackets, thence reacting backward between the nozzles and passing thence between them from all points and concentrating and passing through the twyer h into the furnace. As these pipes or nozzlesf, attached to or for ling part of the diaphragm e, are very close together throughout the whole surface of the diaphragm and terminate in the inner chamber of the jacket very near to the fire-wall 71), it follows that the whole of the air-blast passing through these small pipes f under pressure is made to impinge sharply against the fire-wall throughout its whole surface, and thus the heat constantly imparted to the fire-wall 7c of the jacket from the interior of the furnace is as constantly taken up by the air-blast and carried back into the furnace through the twyers h. The jacket-sections Z) and the conduitgirder c being far above the smelting-zone of the furnace, and hence not exposed to Very great heat, are kept sufficiently cool if made hollow or in single chambers, as shown, and the airblast blown through them without special device for making the airiinpinge against their heated surfaces.

A safety clack-valve (Z is held in closed position, as shown,when the blast-pressure is on, but opens downward by its own weight when blast-pressure ceases, thus allowing inflammable gases to escape to the atmosphere that may have backed out from the furnace into the jacket when the blast is stopped.

I claim 1. In a furnace for smelting ores and other purposes, a metal jacket or series of jackets, a diaphragm or partition dividing the jacket and having manysm all pipes, suitablyspaced throughout its area, extending toward the inner or fire wall of the jacket-section in order that air under pressure in the back chamber shall be forced through the small pipes or nozzles or openings in the diaphragm and caused by its pressure to impinge with greater or less force against the fire-wall of the jacket, thus to abstract from the fire-wall the heat that it is constantly absorbing from the furnace, the inner chamber of the jacket being of such dimensions or the distance from the diaphragm to the fire-wall sufficiently great to allow ample room for the air to react or rebound from the fire-wall and to pass along the diaphragm between the pipes fwithout excessive obstructions or friction to the twyeropening in the fire-wall, and hence into the furnace, substantially as described.

2. In a furnace, an air-jacket having a diaphragm dividing said jacket into sections, openings through the diaphragm means for forcing air therethrough in a series of jets, an upper jacket Z) and a conduit-girder located above the jacket I) and in connection therewith, said girder being made hollow to form a passage for the air-blast, substantially as described.

In a furnace, an air-jacket (I, for the lower zone of the furnace, openings therefrom to the interior of the furnace a girder serving as a support for a superincumbent structure, said girder being hollow to form a passage for the air-blast, a jacket I) below the girder and connected therewith and a connection be tween the jacket I) and the jacket CL.

4:- In a furnace, a hollow girder, a structure supported thereby, a jacket I), a connection between the same and the girder, a jacket a and a connection between the jacket I) and the jacket a, with a safety-valve in said connection, and openings from the jacket a to the interior of the furnace, substantially as described.

In testimony whereof I affix my signature in presence of two witnesses.

JOHN IV. NESMITII.

\Vitnesses:

W. O. MACDONALD, J OHN MoCANN.

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