US357442A - Steam-boiler furnace - Google Patents

Description

(No Modl.) 2 Sheets -shet 1. J. R. YOUART.

.STEAM BOILER FURNACE.

Patents Feb. 8, 1887.

(No Model.) 2 Sheets --Sheet 2.

JR. YOUART.

STEAM BOILER FURNACE.

Patented Feb. 8, 1887.

wit names 1 Suva/M 606 n. PETERS, PholoLithognphcr. Washlnglnn, 1) c NITED rarns JOHN R. YOUABI, OF TIPPEOAIVOE CITY, OHIO.

STEAM-BOILER FURNACE.

SPECIFICATION forming part of Letters Patent No, 357,442, dated February 8, 1887.

Application filed October 8, 1886. Serial No. 215,714. (No model.)

To aZZ whom it may concern:

Be it known that I, JoHN R. YOUART, a citizen of the United States, residing at Tippecanoe City, in the county of Miami and State of Ohio, have invented certain new and-useful Improvements in Steam-Boiler Furnaces; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to improvements in furnaces designed for use in heating steamboilers and for other similar purposes.

The present. improvements relate more especially to the setting of the boilers, and consist in providing the boiler witha series of depending arches or division-plates upon the upper ends of which the boiler rests, and which form pockets within which the hot air is contained and rests against the boiler-bottom, and so that the flame from the furnace shall pass across said hot-air pockets and heat the air therein and the bottom ofthe boiler by the radiated heat of the passing flame.

In the accompanying drawings, Figure 1 represents a longitudinal sectional elevation of asteam-boiler furnace constructed according to one form of my improvements. Fig. 2 represents a transverse sectionthereof on the line 2 2 of Fig. l, and Fig. 2 a similar view on the line 3 3 of Fig. 1. Figs. 3 and 4 represent perspective views of modifications.

Where in furnaces for steam-boilers it is sought to project the flame against and keep it in contact with the boiler, such principle is wrong, for the flame does not and cannot touch the boiler, for the reason that the temperature of the boiler is below the point of ignition of the gases generated by the combustion of the fuel, and when it is sought to cause the flame to impinge upon the bottom of the boiler the flame is therefore extinguished by the boiler and results not only'in making combustion incomplete, but a dark layer of air and unconsumed gases intervenes between the flame and the bottom of the boiler, which gases and air,'although cooler than the gases or air below them, would, were there no currents, descend and give place to the warmer gases, (as heated or rarefied air always ascends,) are kept by the ascending and onward currents of hot air and the gases of combustion in contact with the boiler until the rear thereof is reached. No non-conductor is as perfect as air or gases, and as the speed with which the conducted heat is absorbed by a body is in direct ratio to the difference between its own temperature and that of the source of heat in direct or absolute contact with it, little of the heat of combustion isabsorbed by the boiler, for the temperature of the unburned or partially burned gases in contact are, generally below 400 Fahrenheit.

The prime object of my invention is to keep the flame from the boiler, to secure the heating thereof by the radiated heat from the flames, and also to secure the perfect combustion of the gases. The small amount of flame that might be extinguished by coming in contact with any part of the boiler or other comparatively colder surface, and resulting in unconsumed gases, would not be suflicient to affect the advantageous features of my invention, for the reason that should any of such unconsumed gases be created they will, through the medium of the radiated heat of the passing flames, be drawn down and out of said hot-air pockets to the flame and consumed.

By constructing the divisions in arch form, as representedin Figs. 1 and 2, and providing said arches with one or more openings therein, as shown, all the gases of combustion are concentrated and heated and kept to the tempera ture required'to complete combustion. In this way I prevent the contact with and retention against the boiler of partially-consumed gases and allow a higher degree of heat to come in contact with the boiler by the radiation of the flame. At the same time I secure a more complete combustion of the gases, and consequently secure the application of a larger amount of heat to the boiler than could be obtained if I attempted to secure flame contact with the boilers comparatively cold surface, for, owing to the fact that the temperature of the surface of the boiler at fifty pounds pressure is only about 300 Fahrenheit, while the temperature of the flame is generally from 3,000 to 4,000 Fahrenheit, it will readily be perceived that the effect of the contact of the flame with the comparatively cold surface of the boiler will result in quenching the flame, producing a strata of unconsumed gases,which remains in contact with the boiler and prevents the increase of temperature desired. My arches or division-plates will not only prevent the generation of unconsumed gases resulting from flame contact with the boiler and the retention of the same in contact with the boiler, but said perforated arches will, moreover, concentrate the heat and insu re the perfect combustion of all the gases by the heat generated.

1 represents the steam-boiler; 2, the firebox or combustion-chamber of the furnace; 3, the grate, and 4 the ash-pit.

5 represents the bridge-wall at the rear of the combustion-chamber, which wall is, according to one part of my improvements, constructed in arch form, as shown in Figs. 1 and 2, with a concaved upper portion, 6, to receive, and within which the forward portion of the boiler rests and is supported. 7 This arched bridge-wall is formed at any suitable distance below its top with a transversely-extending arch-shaped contracted passage or opening, 7, through which the heated air and flames pass to the space 8,rearward of said bridge-wall,the heated air ascending to and impinging against that portion of the surface of the boiler within the space 8, while the flames passing through said opening 7 in the bridge-wall assist inheating the bottom plates of the boiler bythe radi ated heat of the flame, the radiated heat from the flames passing through said opening 7 also maintaining the air within the space 8 at its maximum heat; and by reason of there be ing no possibility of cold air reaching the boiler during firing, owing to there being no space between the top of the arch and the bottom of the boiler, and also owing to the fact that all air to reach the bottom of the boiler must first pass through the combustionchamber and through the heated front arch forming the bridge-wall and in contact with the concentrated flame, a constant supply of highly-heated and rarefied air is maintained in the top of the several spaces or pockets-8, and in contact with the boiler, the highly-rarefied condition of such air being maintained by the flames which pass through said openings, but do not ascend to contact'with the boiler, and by the radiated heat therefrom. Rearwardly of the front arch or bridge-wall are an alternating series of similarlyperforated arches and spaces, as 7 S, and the flame passes successively through the entire series of such perforated arches and the spaces between the same, a supply of highly-heated air being thereby constantly maintained in contact with the boiler, by reason of the ascent within the several spaces or air-pockets 8, between the arches, of the constant supply of heat from the passing flame by radiation as the radiated heat of the flame rises within such spaces and displaces and draws down the cooler air and gases therein into contact with the flames passing through the openings 7, which passing flames consume any unconsumed gases there may be and reheat the air and carry the same through the next perforated arch of the series to the next space 8, within which the radiated heat from the flames rises to contact with the boiler, displacing the cooler air in contact therewith, and so on throughout the series of perforated arches and intervening spaces.

One or any greater number of such transverse areh-shaped contracted perforations 7 may be formed in the several arches, and the number may be uniform or otherwise, as desired. The several perforations. 7 in the re spective arches are in or about in line with each other, sufficient space being left between their tops and the bottom of the boiler to leave a pocket or chamber at the upper portion of each space 8, within which the rarefied air may ascend and operate upon the boiler without permitting of the direct contact of the flame with the boiler-bottom. By this construction the draft will always draw down the unconsumed gases and the partially-spent heated air and products of combustion, and permit of the ascent of the hotter air into contact with the boiler.

In Figs. 3 and L I have represented slight modifications of the perforated arches heretgfore described. These modified forms practically represent the furnace as it would appear were the perforated arches cut away from the bottom of the perforations 7 therein. In this construction, in lieu of extending the arches or division-walls 6 from the top to the bottom of the space beneath the boiler and providing them with an opening or openings, 7, through which the flames shall pass, as be fore described, I either attach to the side walls, a, of the furnace a series of short division plates or strips of absestus, i), or other suitable material, whose upper ends closely connect with the bottom of the boiler and depending therefrom a short distance, as represented in Fig. 3, so as to form pockets 8, within which the hot air shall ascend and remain in contact with the bottom of the boiler. The front division wall or strip, I), may depend above the top of the bridge-wall or in front thereof, as desired. In either arrangement it will act as a barrier to the ingress of cold air, when firing, to and striking against the boiler-bottom; or I form such divisions of any suitable refractory material, as fire-clay, and build the same against or rest the same upon ledges or flanges 0, extending inwardly from the inner side walls of the furnace, after the manner represented in Fig. 4. In either of these arrangements the flame, as it is drawn from the furnace or combustionchamber by the draft, will pass, as represented by the arrow, across the bottoms of the depending divisions, which are of contracted curved shape, as shown at d, so as to contract and concentrate the passing flame, and across the hot-air pockets or spaces 8, and the boiler will, in the arrangement shown in Figs. 3and 4 equally with that shown in Figs. 1 and 2, be heated by the radiation of the heat of the passing flames, and such flames will ICC also be prevented from coming in contact with the boiler, as before described.

In each of the arrangements shown in the drawings the heating of, the boiler is effected by the radiated heat from the flames passing along from the furnace to the rear of the boiler, and only highly-heated air is permitted to come in contact with the boiler-bottom. In each instance, owing to the contact of the flame with the boiler being entirely prevented, and said flame being compelled to. pass directly along from front to rear, the perfect combustion of the gases is assured by the time the rear of theboiler is reached, and when the rear of the boiler is reached the products of combustion may be either passed in a return direction between the tubes of the boiler and out through a suitable flue at the front end, or they may be discharged in any other suitable manner.

By thus providing a steam-boiler with division arches or plates in contact at their upper portion with the bottom of the boiler, and having either transverse perforations or passages therein or a contracted curved lower portion, the flame, as it passes along from the furnace or combustion-chamber to the rear of the boiler, will necessarily be concentrated and its heat intensified, the gases of combustion thoroughly intermingled with the flame, and perfect combustion thereby secured, and the concentrated flame, as it is drawn in a direct line across the air-pockets 8 and through the Y openings 7 or contracted curved portions 01,

will radiate a very high degree of heat, which will operate against the boiler and secure the rapid and high heating thereof.

In some constructions of furnaces it may be found desirable to form some or all of the supporting-arches with two or more flamepassages, 7, to secure the requisite concentration of flame and intermingling therewith of the gases of combustion. In some cases the perforated arches shown in Figs. land 2 could not be as conveniently employed as could the division-plates shown in Figs. 3 and 4. Such division-plates could be more readily applied to boilers and boiler-furnaces already constructed and in use, and at comparatively slight expense. In either case, where either the perforated arches or walls or the divisionplates, as represented, are employed,the same advantageous results are secured.

Having thus described my invention, I claim- 1. A steam or locomotiveboiler furnace having a bridge-wall vertically above the rear of and inclosing the furnace, the upper end or edge of said bridge-wall snugly fitting and embracing the bottom of the boiler and having at a suitable distance below its top a contracted curved passage through which the heated air and flames pass, so as to prevent cold-air contact with the boiler-bottom during firing and also prevent flame contact with the boiler rearwardly of the grate, substantially as set forth.

2. A steam or locomotive boiler furnace hav ing a bridge-wall directly above the rear wall supporting the grate, the upper portion of said bridge-wall being of a shape corresponding with the shape of the boiler-bottom and snugly fitting the same and having at a suitable dis tanee below its top a contracted curved passage to permit of the passage therethrough,in a concentrated form, of flame and heated air, jointly with a series of walls or divisions rearwardly of said bridge-wall, the upper portions of said walls or divisions also embracing and snugly fitting that portion of the boiler-bottom immediately above the same and each having one or more contracted curved passages and being arranged in sufficiently close proximity the one to the other to form air receiving and holding chambers or pockets and to permit of the ascent therein of heated air, insure the passage of the flames across said pockets, prevent the ascent of the flames therein, and secure the heating of the boiler by the heat radiated from the passing flames, substantially as set forth. 7 p

3. In a steam or locomotive boiler furnace, the combination, with the customary furnace or combustion-chamber, ash-pit, and boiler, of aboiler setting or support composed of a bridge-wall and a series of divisions rearv wardly thereof and removably attached in position, said bridge-wall and divisions being in close contact along their entire upper edge with the boiler and having contracted curved passages below their tops, substantially as and for the purpose set forth.

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

v JOHr R. YOUARI.

\Vitnesses:

CHAS. J. GoocH, S. A. TERRY.

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