US449379A - Sectional boiler - Google Patents

Description

4 Sheets-Sheei 1L (No Model.)

J. H. MILLS. SEGTIONAL BOILBR.

Patented Mar. 3l

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(No Model.)

4 Sheets-Sheet 2.

J. H. MILLS. SBGTIONAL BOILBR.

Patented Mar. 31, 1891.

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4 Sheets-Sheet 3.

(No Model.)

J. H. MILLS. SBGTImLM.4 BOILER.

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(No Model.) 4 Sheets-Sheet J. H. MILLS.

SBGTIONAL BOILER.

Patented Mar. 31,1891.

l UNiTnD STATES PATENT Tirion.'Y

.lOl-IN l'fl. MLLS, OF BOSTON, MASSACHUSETTS.

SECTIONAL BOILER.

SPECIFICATION forming part of Letters Patent No. 449,3? 9, dated March 31, 18911.

Application tiled November 15, 1890. Serial No. 371,609. (No model.)

To a/ZZ when?, it may concern:

Be it known that l, JOHN H. MILLS, a citizen of the United States, residing at Boston, in the county of Suffolk and State of Massachusetts, have invented new and useful Improvements in Sectional Boilers,of which the 'following is a specification.

This invention relates to sectional boile1s,` the object being to provide for steam and especially for hot-water-heating` apparatus and analogous uses an improved boiler consisting of cast-iron hollow sections of peculiar construct-ion and arrangement composing` the individual units of `such boiler, whereby increased heating-surface. is obtained without increasing the cost,A of manufacture, all as` hereinafter fully set forth.l

lathe drawings forming part of this specification, Figure l is a front elevation, partly in section, of a boiler embodying inyiinprove ments. Fig. 2 is a side elevation, part-ly in section. Fig. 3 is a sectional View about on line 3 3 of this figure. Fig'. 4 is a rear viewof a section located at the rear end of the gratebars, as belowtdeserib'ed. Fig. 5 is a perspective view of one of the main sections of the boiler, the outflow and return drums with which all of the sections of the boiler coinrnunicate, and a pipe connection between said drums, the purpose of which is fully described below.

One essential object of this invention is to secure increased et'iiciency and power to absorb heat for a liquid circulation by placing a part of the heating-surface below the grateline, which surface will be acted upon by the radiant heat of the coals on the grate and the high temperature of the ash-pit, but which heat is entirely lost in boilers havin g no heat* absorbing' surface below said grate line. lVhile some wroughtiroii or shell boilers have an extension of their water-spacesbelow the grate-line and tothe door, they de not and cannot also extend their smoke-dues to render available the surface so obtained.

lleretofore in the construction of eastnnetal boilers composed of separate sections they have been formed of certain tubes and fines designed to stand upon foundationfwalls of brick or iron, such walls forming the ash-pit of the completed boiler.

lVhile the sectional boiler just referred to erate steam as the heating agent, but to raise the temperature of the water siniplyand circulate it in pipesor radiators located in the rooms and spaces to be warmed. There is another and important advantage secu red when using this boiler for circulating wa` ter instead of steam as a lient medium. This is the increased height of the columns of water acted upon by the heatduie to the longer section obtained when starting from the floor and the fact that this pipe conveying the return circulation may enter the boiler also on the floor-level' and without rising' up and forming' a loopin the return-pipe1 which is a loss of power and efficiency proportioned to the distance which such return- .pipe rises before entering' the boiler.

I-Ieretofore in the construction of sectional boilers, whether composed of whole sections spanning the grate and [ire-chamber from side to side, or as divided sections covering One-half of the `crate, the sections are con strueted to be elevated and stand upon a brick or iron foundation, which also forms the ash-pit walls of the completed boiler. [n my present invention, however, I dispense with all brick and iron foundations by constructing my boiler-sections to standdirectly on the floor, the lower part of such sections Y below the grate-line forming their own. fou ndation, and thus avoiding` the expense of brick or iron ash-pit walls and the labor of elevating` the heavy castings onto the foundationgenerally half a yard above the lfloor. This method of constructing` cast sectional boilers notonly dispenses with said common but useless .foundations as to heat effect upon the water in the boiler, but by formino: the same from the sections themselves increased heating-surface is obtained in the pipes and tubes extending below the grate and forming' the walls of the smoke-titles before described.

In the drawings, A indicates the main integral sections of the boiler, each et which is of cast-iron and hollow, and consists of (see Fig. 5) two substantially parallel vertical tubes 4f 4, united by a hollow base 5 at their lower ends, and having,` extending therebe` IOO tween at intervals and communicating with the interiors thereof several (three being the preferred number) cross or horizontal ducts (i, 7, and S. The said vertical tube 3 of the boiler-section A terminates at and communicates with the interior of a horizontal crownpipe t) integral therewith and with other tubular parts of said boiler-section, hereinafter referred to,and said vertical tubc4 has a curved upper end,as shown, which terminates at one end of said crown-pipe and, like the tube 3, communicates with the interior thereof. Three tubular branches 10, 12, and 13, constituting elements of said boiler-section A, are arranged one back of the other relative to a central vertical line y2 through the boiler, as illustrated in Fig. 1, said branches extending from the side of said tube 3 in curved or quarter-turn lines and terminating at the under side of and communicating with the interior of said crown-pipe 9. Said branches are also integral wlth the said tube 3 and crownpipe and occupy positions over the grate 14, and are thus directly exposed to the hcatof a tire built thereon. Said sections A are so constructed and arranged side by side, as shown iu Fig. 2, on the opposite sides of the tire-box within the boiler as to leave open draft-spaces :1: between the ripper parts of the sections, and thelatter have cast upon their adjoining sides below said draft-openings .oc projecting lips fr, whose edges are brought into engagement when the sections are in place side byside,thus closing up any opening between the adjoining sections from thelowerend of said l raf t-spaces to a point a little above the grate 14, and there the said closing lip 'u takes a somewhat different direction, as shown, and terminates under the grate, and from the latter-named point the lip t 'extendsdownward to thelower end of the pipe 3, so that when the sections are grouped side by side, as shown in Fig. 2, a close wall will be thereby formed on the opposite sides of the ash-pit. From the upper side of the grate a perforated lip w extends in a like manner from the side of the tube 3, and its upper end terminates at the lower end of that portion of the lip /U which terminates.

near the duct 7. By means of the form given to the lip lv between the duct Gand 7 an airbox ly is formed when two sections A are brought together between said sections through which air may flow from the ash-pit B to a point over the tire on the grate, said air passing through the perforations 0 in saidlip tu, this latter-named perforated lip, together with the adjoining flat side of the tube next tothe grate, serving as a part of the side wall of the 'ircbox. The said provision for the circulation of air from the ashpit B through the box y and the perforations o to mingle with the products of combustion in the fire-box affords means for supplying the tire with oxygen, whereby the fuel is consumed under the most advantageous conditions. It will be understood that by means of the abovedescribed construction one of said air-boxes "ll/ is formed between thcV sides of adjoining sections.

The opposite sides of each of the ducts G of the section A are provided with a horizontally-extending lip n, having acurved central notch e two of which form the draft-opening K, (see Fig. 3,) and whose outer edge is in a plane at one end with the edge of said 11p e and its opposite end is in a plane with the edge of a Vertical lip m, extending from the side of said tube 4 to the same extent that said lip lv extends from the side of the tube 3, said lip m, however, extending from the lower end of said tube 4 along its side to the crownpipe 9, and along the side of the latter to its extremity, as shown in Fig. 5, to the end that when the sections .A are brought side to side, as in Figs. 1 and 3, the edges of said lips m, r, and yn shall closely abut, thereby compellingthe products of combustion from the fire to pass in the direction indicated by the arrow c at the top of the sections, through the openings a', and thence downward past the ducts S 7 (3, through the draft-opening K,to the main draft-flue 71. on opposite sides of the ash-pit B. The said main draft or smoke tlue h, of which there are two,one on each side of the ash-pit under the grate 14,is formed within that part of the several boiler-sections A surrounded by the lower ends of the tubes 3 and 4 and the ducts 5 and (3, and consequently when the several sections A, which comprise the sides of the boiler, are united together, as shown in Figs. 2 and 3, there is thereby formed said smoke-fluehatthelowerendsofandwithin the above-referred to parts of the sections A, such flue being thereby constructed on each side of the boiler and being continuous from the front to the rear side thereof, as clearly indicated in Fig. 3. In this last-named figure, and also in Fig. 1, the dotted lines z indicate the position of the brick-work, within which when the boiler is set the same is inclosed in the usual manner, and in Fig. 3 the dotted lines i indicate the position of a chimney, and the lines i2 the direction of dues that in practice extend from the rear ends of the tiues 71, in the lower ends of the sections A to the chimney. Itis thus seen that by means of such flue connection with a chimney a direct draft from each flue h is provided, whereby the products of combustion are compelled to move from the tire-box upward among the branch tubes 1b, 12, and 13 of the several sections A of the boiler, thence through the passages x between said sections, and thence downward between the walls of a chamber consisting of the vertical tubes. 3 and 4 of said sections,

past the ducts 6, 7, and S, and thence throughr the openings K (sec Fig. into said smoketlue h, and thence to the chimney, as aforesaid. lt will be seen also by reference to Figs. 1, 3, and 5 that the side walls of the ash-pit B consist of the united lower ends of the said tubes 3 of the sections A, and therefore the heat existing in the ash-pit acts directly .against said walls to impart heat thereto and IOC IOS

IIO

to the water contained in those portions of` lirst and most directly against the surfaces of the said branch pipes 10, 12, and 13, which are directly over the grate, and in which the water contained in the boiler is found at its highest temperature, and thence downward, as above described, to the fines h, giving off the heat to the surfaces of the boiler-sections as it passes along. By this means it is clearly seen that the heat'generated in the lire-box acts continuously and only against the surfaces of the boiler-sections which contain the water to be heated from the time it escapes from the [ire-box until it reaches the auxiliary flue above referred to between the boilerand the chimney, and by this means the entire efficiency of the products of combustion is utilized for heating purposes, it being well understood that a boiler connected with a hotwater heating system receives the return-current from the radiators at its lowerrnost point, and consequently the water 1n the boiler which surrounds those portions of the boiler-- sections which constitute the walls of the smoke-fines 7L is found to be of a lower temperature than that of the products ofcombustion, which are delivered into said fines from the lire-box, and hence the water surrounding said fines has its temperature raised more or less after reaching said lowest point in the boiler. Furthermore, the radiant heat from the ash-pit against the side walls thereof, as aforesaid, also contributes to the raising of the temperature of the water in the lower flue-containing ends of the said'boilersections A.

The above-described advantages pertaining` to the construction of the lower draft-fines 7L within the sections of the boiler are wholly lost when such I'lues are constructed of brickwork, as heretofore practiced, beneath and upon which the lower ends of the boiler-sections rest. The said boiler-sections A have their upper ends connected to the opposite sides of a flow-drum D-that is to say, the drum toward and into which the water heated in the boiler-sections liows and from which said heated water flows or passes off through an opening J in the rear of the drum or a similar opening or openings J2 in the upper side of said drum. A suitable conducting-pipe is connected thereto leading to the heating-pipes or radiators. Connection between said sections Apand the drum D is made by means of an elbow 15, preferably cast on the crownpipe 9, and a short connection-pipe 1G, connected by one end with said elbow and its opposite end screwed into a socket 18 on the side of said drum, a packing-nut 17 being` placed on said pipe 16 and screwing against the face of the socket 18 to lock and pack the joint between said pipe and the drum, any suitable packing being interposed therebetween, if desired.

A return-drum E is located at thc lower oud of the boiler and at the vlowest point thereof and in axial alignment with the flowdrum D and extends under the ash-pit B from the front to the rear side of the boiler, as shown in Figs. 23 and 5, and the lower ends of the boiler-sections A are connected to said return-drum by means of a pipe 19 for each section, suitably connected by one end thereto and having its opposite end connected to the drum E in substantially the same manner as is one end of said pipe 16 connected to the drum D, a similar packing-nut 2O being employed, preferably, at the drum-connected end of said pipe 19. The return-pipe from the heating pipes and radiators is connected t0 the rear end of said drum E at the opening f (see Fig. 2) or other suitable point thereon. An ash-pit floor of iron covers the drum E and connecting-pipes 19.

The above-described arrangement of the drums D and E in axial alignment one above the other and centrally between the sections A, together with the long pipe connections 19 between the lower ends of said sections and the drum E, permits the vertical expansion of the sections wit-hout injury to the joints of the sections and connecting-pipes; A hollow tubular section C, constituting a movable bridge-wall, (see Figs. 1 and 4,) is constructed and adapted to be located at the rear side of the tire-box, as shown, andis connected by its upper and lower ends to an intermediate connection-pipe 21 between the drums D and E at l) and b2 thereon by suitable connectin g-pipes,which con n ecting-pipes may be longer or shorter, according to the length of the grate-bars which it is desired to employ, whereby said section C may be correspondingly adjusted relative to the rear end of said bars. By this means the water contained in said section C becomes heated by its exposure to the fire and flows off atb into the` pipe 21, and through thelatter into the drum D, the return-current passing from the drum E into the pipe 2l at b2, and flowing from thence into the lower end of said section C, the lower end of which constitutes the rear wall of the ashpit and its upper end the rear wall of the reboX. A rib or lip p (shown in dotted lines in Fig. 4t) is formed on the front side of the said wall C, directly opposite the rear ends of the grate-bars, to prevent coal from dropping therebetween. The spaces between the vertical tubes of the bridge-wall are closed by a web to prevent any rear draft therebetween.

Having fully described my invention, what I claim, and desire to secure by Letters Patent, is*- 1. A metallic boiler-section A, consisting of the integral combination of thev following members, forming one unit of a sectional boiler, viz: the main vertical pipes 3 el, having horizontal cross-pipes 5, ti, 7, and S, the said pipes 3 and 4 uniting in a crown-pipe 9, and the curved pipes 10 12 13, whereby is formed the requisite intcrconn ectin g internal IOO IIO

water-passages, and, in a group of said sections, the external vertical and horizontal ilues to receive and conduct the products of combustion over the entire surface thereof `before their exit to a chimney, substantially as set forth.

2. A sectional boiler consisting of a number of hollow metallic sections arranged in two independent groups on opposite sides of the tire-box, each of said groups having therein at the lower end thereof below the tire-grate an independent horizontal smokeiiue communicating with the chimney and receiving the products of combustion through openings in its upper side, the surrounding walls of which flue are composed of grouped portions of said hollow sections, substantially as set forth.

3. A sectional boiler consisting of a number of hollow metallic sections arranged vertically side by side in two independent groups on opposite sides of the tire-box, each of said groups having therein at the lower end thereof below the lire-grate an independent horizontal smoke-flue communicating with a chimney and receiving the products of combustion through openings in its upper side, the surrounding walls of which flue are composed of grouped portions of said hollow sections, substantially as set forth.

4. A sectional boiler consisting of a number of hollow metallic sections arranged in two groups on opposite sides of the tire-box, each of said groups havingtherein at the lower end thereof below th eiire-grate ahorizontal smoke- 3 iluccommunieatingwithachimneyandreceiving the products of combustion,thesurrounding walls of which are composed of grouped portions of said hollowseetions, combined with a hollow bridge-wall arranged vertically at the rear ot' the ashpit and tire-box, and a flow and a return drum, with which said sections are connected, substantiallyas set forth.

5. In a sectional boiler, a receiving and a discharge drum, one above the other in axial 4 alignment, to which said sections are connected, combined with a vertical hollow bridge-wall section located at the rear of the grate-bars, having water-circulating connections with said drums, substantially as set forth.

6. Ina sectional boiler, a receiving and a discharge drum, one above the other in axial alignment, to which said sections are connected, Combined with a vertical hollow 5 bridge-wall section located at the rear of the grate-bars, having variable water-circulating connections with said drums, whereby the bridge-wall section may be set at different distances from the front side of the fire-box, substantially as set forth.

JOHN Il. MILLS.

Witnesses:

H. A. CHAPIN, G. M. CHAMBERLAIN.

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