US853099A - Fire-box for steam-boiler furnaces. - Google Patents

Description

PATENTED MAY J. LIVINGSTONE. FIRE BOX FOR STEAM BOILER FURNACES.

APPLIOATION FILED JULY 21, 1906.

2 SHEETS-SHEET 1 n w m \N N M m6 m N L N H Q w BYM t" v ATTORNEYS PATBNTED MAfi, 1907.

J. LIVINGSTONE. FIRE BOX FOR STEAM BOIL ZR FURNAGES. APPLICATION FILED JULY 33 SEEETS-SREET 2-.

q ATTOHA/E r9 rmrr'nn shares ge r r nn'r ora on.

JOHN LIVINGSTONE, MONTREAL, QUEBEC-,CANADA,

' FIRE-BOX FOR STEAM-BQELER FURNAQES.

To all whom it may concern.-

Be it known that 1, JOHN Lrvmos'ronn, a subject of the King of England, residing at Montreal, Quebec, Canada, have invented a new and useful Improvement in Fire-Boxes for Steam-Boiler Furnaces, of which the following is a specificationf v My invention is in the nature of certain improvements in the fireeboxes of steam boiler furnaces and especially the furnaces of locomotive boilers.

' It is designed to accomplish several im-- portant results, prominent among which are. First, to contribute to the strength and stability of the boiler around the fire-box by maintaining, while-in service, the natural elasticity of the material, avoiding the burn ing of the inner ends of the stay-bolts and avoiding those strains which ordinarily exist between the stay-bolts and the outer and inner walls of the fire box due to high tempera, tures of unequal distribution. Secondly, to

secure a more perfect combustion of, usually,

unconsumed carbon, and thus economize fuel and avoid the nuisance of smoke. Thirdly, to assure a continuous production of free l1ydrogen in the fire-box and fourthly, to give relief from explosion.

The instrumentalities invented by me for securing the results under-the first heading are precisely the same as those which accomplish the results under the second, third and fourth headings and these instrumentalities consist in a very simple and practical appli 5 cation of hollow stay-bolts which, While notnew in themselves, involve, when constructed and applied in accordance with my invention, the most important results in 4 steam boilerfurnaces.

Figure 1 is a vertical longitudinal section through the fire-box of a locomotive boiler.

' Fig. 2 is a vertical transverse section through the same, on line 22 of Fig. 1. .Fig. 3 is an enlarged central section of one of the crown stay-bolts and Fig. 4 is a similar view of one of the horizontal stay-bolts as used at the sides, back and front of the fire-box.

In the drawing, A represents the outer wall and B the inner wall of that portion of a locomotive boiler which surrounds the firebox 0.

D are stay-bolts WlllCll connect the crown sheet of the furnace to the top portion of the outer wall and E are stay-bolts which 0011- nect theouter and inner walls atthe sides,

bolts E. 'As't back and front ends of the fire-boar.

' Specification of Letters Patent. Application filed July 21,1906. Serial No. 327.157-

Patented- May '7, 1907.

The stay-bolts as shown are all screw threaded their entire length, but they may be I threaded only at the ends where they pass, through the outer and inner walls of the I prefer the Vhitworth standard to the l-threads.

boiler.

7 Their outer ends are firmly rivetedor upset to form heads or they may be made fixtures in any other suitable way.

The horizontal stay-bolts E, vsee- Fig. 4;, have acentral longitudinal hole a through them from end to end and embody, no constructive novelty. The stay-bolts D, of't lie, crown sheet are, however, specially constructed, as seen in Fig. 3.- They have a centralglongitudinal hole (1, which does not go all the way through, but stops short of the outer end of the stay-bolt, so thatit does not communicate with theouter air. It does go all the way. through the inner end of the bolt, however, and it cornmu nicates wit a number of small holes dzl. drilled transversely into the stay-bolt'and opening on the outer side into the steamspace in the boiler be tween its two walls, sc -that steam from the steam space may gain access to the central, hble in the stay-bolt and flow in a'small stream into the fire boX. The steam ex.-

pands in the central hole; it there meets and fusion of the heat is qhickened to the outer wall; the side sheets, back head and front end receiving the radiant'heat-of the fire at the same time as the crown sheet, and all at the same time with the radiant heat up (Z and by conduction up D and by diffusion througlf the water, and with the heat at the outer wall confined by the lagging, an equilibration of the temperature between the two walls is attained. The service of the steam in the central hole (1 is also of value to the materiahin that, whereas in solid stay b'olts theimate'rialbeicomes fatigued and weakened. in service, it saves and sustains the material in its elastic strength, provided the iron is freefrom the brittleness. The central hole d is also a safety hole in case of breakagefor though the natural supply of steam from openings (1 is invisible, the breakage of a bolt would cause a visible 'escape of steam to give notice of suchbreakagc of'a bolt or bolts, and the same remarks apply" to the opening e in stay s stream of steam. passes through the highly heated end of these staybolts, the issuing steam is invisible, and superheated to the point of disruption into its constituent gases, oxygen and hydrogen. Just at this point two important and simultaneous results may be noted. The first is the cooling of the end of the stay-bolt in the inner wall by the escaping steam and inc'reas' ing the strength, stability, and longevity of the stay-bolt, by taking away its damaging excess of heat, and the second is in utilizing this heat by giving it to the steam, for superheating the same and rendering it susceptible to disruption with the consequent forma-' tion of water gas by, the association of its gases with the incandescent particles of the fuel.

. The streams of superheated steam form,

when disrupted,'fuel gases which mingle with the oxygen of the air passing through the,

lower stay-bolts, and produce an intense combustion which burns up the smoke. and carbon particles.

In the ordinary way of there are three forms of loss from out of the combustibles, irrespective of losses by burn ing coal weighted with constituent incombustibles. The three forms of loss, are; first, the

loss of-the volatile constituents of bituminous coal. Second, the loss by the formation of the always forming carbonic .oxid. Third, the loss by the escape, unconsumechol the carbon particles from the furnace, in part lod ingin the front end, where they accumu ate and impair the draft, and in part as sparks through the smoke stack, sometimes causing fires.

Professor Goss, the scientist of- Purdue University, has determined, by test, that the weightof sparks and cinders, which escape as above, unconsumed, to the front end and outer air, may in connection with narrow fire boxes equal 20 per cent. of the fuel fired. Tlie three forms of loss even with careful firing in the fire boxes generally" in service, may

aggregate 50 per cent. of the weight of the The affinity of hydrogen (1, for oxygen,-

and. the oxygen always present when wanted in never cooling volumes by wav of the tubular channels e n'iail'itains the temperature above the temperature at which carbon ig burning the fuel, I

nites, and (2) the affinity of hydrogen for carbon, makes it the gas to overtake and burn 1n the fire-box the carbon particles which would otherwise escape to the front end as cinders and to the smoke stack as.

sparks. 'When the volatile portion of ti 9 bituminous coal is spread over the red fuel, it rises above the fire bed and. quick as a flash it is in the air as smoke; and when the solid coal under the influence of the incandescent lire bed gives o'll unburned, partly burned, or coked portions called carbon particles, they rise in the furnace and pass throu h the tubes .tothe front end or out of the stac ,and there is no other gas but hydrogen to'overtake'and consume the carbon particles while they are in the fire-box, because there is no othergas equal'to it'in-diifusive and refractive power; 7

it d ifl uses relatively at the rate of four to one foroxygen, the velocity of its atoms is 6,050

ond, all combining with the first stage of burning on-the grate and perfected by the production of hydrogen at (Z and by the union of the carbonic oxid with. the oxygen from Most efforts to superhcat and disrupt steam in a fire-box involve a destruction of the ma tcrial forming the instrumentalities, but in. my invention, it will be seen, that the gassifying of the steam is made to' cure an existing evil, namely, the burning of the inner ends of the stay-bolts, so that l secure two advantageous results without the hitherto attomh ant objections of either, or in other words while securing a great desideratum in stimu-.

lating combusthm, l by the same instrumentalities and at the same timeywithout other expense, dispose of very serious evil, by the preventing of the burning of the inner ends of the stay-bolts and the avoidance-of differential temperature strainsat the anchorage points of the stay bolts in the, walls of the boiler. J It. is Well known that the railway coinpanies are greatly embarrassed 'by the breaka e of stay-bolts. abnormal breakage is in the greater temperature and expansion of the inner sheet (next the lire) acting on the bolts laut 1n the outer sheet of the -[ire-box \vhcrc thc tcxmmraturc is less. That cause produces differential expansion and contraction in the stay- -bolts in. the varying tci'nperaturos of the lire-box, which sooner or later, causes crystallization and breakage. The, danger increases with every bolt broken, sometimescausing cx I plosions and loss of life with appalling uddennoss. When from any cause, the ('onduc tion through the material is impaired, and any part ofthe iron \vn'lun the bo1ler l)e comes red hot, then wager or steam released The allegedcause of tho by a breaking stay -bolt will, in tom-hing the red hot iron, cause a sudth n cxg'losion.

l have det'ern'uned by tests that the gases 85 feet a second with oxygen 1,514, and nitrogen, (which aids the draft) 1,616 feet asec released by disruption may be continuously 1 o frbm explosions in the small holes d d and in the center hole (1, the expansion losing its en ergy'by its dissipation through the fire-box, tubes, and smoke stack in the outer air.

Other dangers arise from burning: When stay-boltends burn, the burning may follow 2o i1npurities from the water.

' heat, the iron loses its cohesion and hardness,

the line of the fibers up the bolt until cooled by the water, and the cooling may not occur until half the bolt is destroyed, especially if it is coated all round with non-conducting In such burning becomes lessened in tenacity, and sometimes its molecular form may be altered to a crystalline structure, and the sheets in expand- 2 5 ing are antagonized the expanding bolts and crack. I

By reason of direct exposure to high heat the ends of stay-bolts exposed to the fire, are

quickly destroyed since theyhave no protection by touch with the air, envelopment riveting thereon.

in steam, or by conduction of their heat at the junction of the bolt and the sheet; their connection there being only a mechanical connection by screwing into the sheet and The tenacity of the iron therefore becomes less, sometimes st much so that it fails to endure the steam pressure, which forces the sheet out from the threads 7 and pulls the head through the sheet.

The railway companies are also continuous losers and the people injured by reason of the excessive waste of fuel, in smoke escaping through the smoke stack, and partly burned coal, escaping as sparks, causing damages I 49am suits for damages, also by reason of the loss and waste of cinders, lost 'to the fire, by

esca ing through the tubes to the front end of t 1e locomotive and thus interfering with the draft. There is also much interference in making steam, by reason of coatings of soot in the tubes, the soot being a non-conductor, preventing the conduction of the heat through the tubes.

Coatings of soot in the tubes come-from ditions whichburn the carbon to carbon di- 'ox'id, and a good natural draft to lead the carbon dioxid through the tubes to the stack,

in its passage it will dissolve the sootin the and outer sheets of the fire-box.

imperfect combustion, but given the con-.

ages, and while adding more to that cost, the

drilling of tell tale holes in the ends, is of dis- My invention in meeting the various objections noted serves 1. To effect an equilibrium in the, temperature between the inner 2.. To increase the steam service fro'm the heating surface without enlargement of the boiler. 3. To quicken the service of heat tothe outer sheet at even time with its service to the "inner sheet by radiation and the uniform diffusion of the heat in the water by conduction; 4. To cause the combustibles now wasted as smoke, the cinde'rs now lost in the front end,-' (there impairing the draft) and the sparks now sent out of the smoke. stack, to be burned,in the fire-'box'. ends of stay-bolts from burning and lessen the expansion of the bolts with relief from cracking, in the expanding sheets. 6. To convert continuously, when in service, the solid fuel into combustible gases. 7. To furnish oxygen to burn the combustible gases formed in the process of burning. 8. To dissolve the soot, as it settles in the tubes; 9. i To promote a draft to aid in the passage of the always forming carbonic acid through the tubes to the smoke stack. 10. To produce and burn hydrogen in the fire-box, -to maintain the temperature and therewith oxygen consume the gases, cinders, sparks, andsmoke, by taking them into union. 11. To give general relief in conditions which cause explosions.

I claim 1. A steam boiler furnacehaving the outer f."

and inner Walls of the fire box connected by hollow stay bolts having solid outer ends and opening into the furnace at their inner ends" and having one or more lateralopenings" establishing communication between the inte rior of the boiler and the hollow stay bolt.

2. Asteam boiler furnace having crown sheet stay bolts formed with solid 0 iter e'nds and steam spaces opening into the fire box.

3. A steam boiler furnace having crown sheet stay bolts formed with solid outer ends and steam spaces opening into the fire 'box and horizontal staylbolts connecting the two walls of the lower part of the fire box and having an channels extending entirely throu h thesame.

"4. hollow stay bolt for a "steam boiler having one end made solid and closed, the other end open and one or inorelateral inlets to the interior between. the ends. 1

' J OHN' LIVINGSTONE. Witnesses:

E. J. FAY, E. H. WEBB.

5. To protect the

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