US1546665A - Steam boiler - Google Patents

Description

July 21, 1925. 1,546,665

F. F. LANDIS STEAM BOILEB 'Filed June 13, 1921 Ai l 1 I. u VI i;

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/5 Frank FLzmdis Patented July 21, 1925.

PHAT OFF l CE FRANK :FL taunts, or wAYnEsBoRo, PENNsYLvANxA.

STEAM normar.Y

Application inea June 1s, 192i. seriai no. 478,563.

T0 all whom if may concern:

lle it known that l, FRANK F. LANDIs, a citizen of the United States, residing at lWaynesboro, in the county ci Franklin and State oit Pennsylvania, have invented certain new4 and useful Improvements in Steam Boilers, of which the following is a specilication.

This invention relates to steam boilers and more particularly to that type or steam boiler known as the vertical lire tube type.

llt is 'frequently desirable to employ com paratively small boilers ot this type under conditions requiring the supplying or steam suddenly and in extremely varied quantities. These boilers are about one-fourth the size ol the ordinary boilers and it is vto this small type oi? boilerV that this invention particularly relates. Such small boilers are most commonly employed for furnishing steam to propel automobiles, trucks, i'arm tractors andin such other places where the available space necessitates the use or a small and light boiler. lt is well known that steam boilers will discharge wet7 steam when working at high heat and with eXtreme 'fluctuations in the demand for steam, such as will occur in the use ot steam automobiles and like machines. Such wet steam is due .to violent agitation .of the water, causing imperfect separation of steam fromV the water, and is generated, for example, when the steam discharge is suddenly increased to a point above the producing capacity of the boiler. Theagitation is greatest at the center oi the boiler, where the water is hottest and least at the sides, where the water is least heated, and this increases the tendency to discharge wet steam, as the outlet for steam is generally over the center of the boiler, where the steam is oftenest wet and to the greatest degree; The discharge ol" wet steam causes a great waste of fuel and therefore the steam space especially in vertical lire tube boilers in commonly made at least equal to the water space; rlhis requires either that the boiler be made needlessly large, or that the water space and the water in the boiler be reduced to a low limit. In stationary engines, especially or the larger types, needless size and weightare not a serin ous matter, but they are highly undesirable in small engines especially of the portable types used to drive vehicles, etc., not only because of the additional weight and size but even more because of the space taken up where space is already very limited. On the other hand it the water space and the quantity ot' water in theboiler are reduced, the area of water in contact with the heating surface is cut down, as also thequantit-y of waterjat abnormally high temperature due to steam pressure, and thus the reserve power of the boiler which lessens the fluctuations in steam pressure on account or varyingdemand for steam or varying fuel consumption is also reduced.

The object ci: this invention is to provide a boiler oi the type referred to which shall be eilicient and economical when employed 'for extremely high duty, and yet be eX- tremely small and compact. y y

Another object of my invention is to provide a steam boiler having an outlet approuimately central of the crown sheet and a baille positioned beneath the crown sheet in such a manner `that the steam generated below the baille must all move tor some distance among and against the heated fire tubes betere reaching the outlet. i

A lurther object is to provide means for drying the steam in proportion to its possible wetness, that generated at the point ot greatest ebullition having the longest travel and impinging most frequently against the heated lire tubes, and vice versa, thereby drying all the steam equally and thoroughly. The wettest steam also takes the most tortuous course, and its currents are most fre-l quently broken up, all or which Yfactors contribute to the desired end. y Y

Referring to the accompanying drawings which are made a part hereof and on which similar reference characters indicate similar parts,

Figure l is a view ot the boiler, `partly in side elevation and partly in diametrical section, showing the present invention applied thereto,

Figure 2 a top `plan view of a iT`ra,g InentV ot the boiler, a part oli the top being broken away to show the crown sheet in plan which is again broken away to show the battle in plan with the tubes in section, and

Figure 3 a detail view showing a modiiied form of baille plate which under some conditions is employed, and which has a screen about the periphery ot the baliie.

Like characters indicate corresponding parts throughout the several views.

In the drawings, l0 indicates a vertical re tube steam boiler of ordinary type eX- cept that it is only from one-third to onehalf the usual height, 1l the crown-sheet, l2 the lire tubes i'itting tightly in the crownsheet, 13 the steam outlet and le the baille plate.

The dotted lines at m in Figure l, indicate the conical shape which the upper surface 01"' the water tends to assume in the usual boiler under conditions of high temperature and excessive steam discharge as above described. The water boils up at the center, flows toward the sides and down along them, inwardly at the bottom and so up again. rlhe wettest steam has the best chance to escape, being nearest to the outlet, and the higher the normal water level the greater the discharge of wet steam and consequent waste of luel.

Vhen my baille is used as shown the upper sui-tace ot the water will assume a less conical shape substantially as indicated by dotted line .e in Figure l, as the steam rising at the middle cannot pass directly toward the outlet, but must pass through the space between the outer edge ot the baille plate and the sides t the boiler. ln its passage much et the wettest steam strikes the barile plate and deposits a part ot' its moisture thereon.

Steam arising from the region at the middle of the boiler in its passage toward the edge o1 the baille plate impinges directly against the portions of the tubes projecting above the water and the currents of steam act substantially at right angles to the tubes and are divided thereby again and again so as to take a tortuous course, whereby the steam is caused to lose any surplus moisture through its contact with the heated tubes. the wettest steam from the central point passing the most tubes and being most trequently turned aside around successive tubes. On passing the baille plate the same process is repeated, all the steam now traveling around lire-tubes between the ballleplate and the crown sheet over substantially the same distance.

ln a high boiler where the space between the crown sheet ll and the normal water lefel (NWL) could be equal to or double the water space below the line, my device mayr be found to have no elliect ot any great value, and I intend it more particularly Ylor those boilers which by reason ot want of space must be low or short and should be light inweight, and especially boilers of the type shownin the drawings. lt is to be noted that the tubes tit the baille le tightly and the only outlet from below the baille to above the same is the narrow annular space around its edge. This is important in maintaining the low water line in the center as indicated by dotted line e.

ln some situations it 'is desirable to use a screen or foraininous curtain, such as shown at l5 (Fig. 3) about the edge ot the baille plate, as where the quality ot water used is unai/*orable tor steam.

iii/whether this last element be used or not, it should be noted taat my device increases the distance traveled by all tl e steam whereever generated, increases the time it remains in the boiler and causes it, and especially the wetter parts, to impinge again and again on the hot lire-tubes, all ol which are ideal factors tor separating water from the steam while passing trom the surtace ot the water to the outlet tube. .lt should also be noted that i utilize about 80% 'of the space in the boiler as water space, instead of 30 to 50%, whereby 80% et the suri'ace ot the lire tubes is iii contact with the water.

Y thus lully described my said invention w1 at claim as new and desire to secure by Tnetters Patent, is:

l. il. st am generator comprising a boiler having vertical tire tubes, aA crown sheet, and an outlet conduit, a batlle comprising a dish embracing the tire tubes and spaced trom the crown sheet forming an annular space between periphery and the periphery of the boiler, l a toraniinous curtain depending from the periphery ot the baille.

curtain depending trom the periphery ol" the baille.

ln witness whereof, l have hereunto set my hand and seal. at T.'lfaynesboro, Pennsylvania, this 9th day or" June, A.. D. nineteen hundred and twenty-one.

FRANK F, LANDS. [n s] liitnesses NLS. LANDIS,

RVING G. HALL.

A steam generator comprising a boiler

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