US2408428A - Means for retarding cinder cutting - Google Patents

Description

Oct. 1, 1946. -w. B. LEAF MEANS FOR RETARDING CINDER CUTTING Filed March 2, 1945 2 Sheets-Sheet 1 WALTER B; LEAF v INVENTOR.

A d,7fl7f%w- "Arromvzsk Oct. 1, 1946. I w. B. LEAF MEANS FOR RETARDING CINDER CUTT ING 2 Sheets-Sheet -2 Filed March 2, 1943 Mum B. LEAF" Y INVENTOK.

A rromvgx ducing the velocity of ga s Patented Oct. 1, 1946 This invention relates to means for retarding cinder cutting in fire boxes and more specifically,

in the fire boxes of steam locomotives.

In many locomotive designs,the fire boxis divided into upper and lower combustion zones: 'by an arch member causing the rising gases to flowfirst in one direction until the end of the arch is reached and then turn and 'flow in areverse direction until the gases pa's'sinto the fines in the boilertube zone. I

In such amovement, the gases reacmhighv'elocities and. assume definite courses of travels'o spaced as to create areas of partial vacuum,

which induce a circulatorymovement of the high Velocity gases into such spaces.

do not receive their proportionate share of the gases of combustion-and become plugged with cindersinarelative'ly short time.

Likewise, the uneven distributionof the gases of combustion causes cinder cutting of tubes, flues; superheater units, flue sheets and crown bolt headsin the areas where the'high velocity gases contact such members.- Particularly, at

the end of the arch, the gases whip rapidly around and travel in'the opposite direction in a v space limited to from one-third to one-half of the total space between the arch and the crownsheet.

It is an object of the present inventionstoflprovide a simple, economical and efficient'me'ans for directing and controlling theflowof'gases in a As 'a' consequence of this action, the lower fines of the boilers nested series of fire bri bo'dying other features' cf the present invention;

Figure 4 is a section takenalong m nner-4,

Figure 3.

Referring first to the formof the invention illustrated in'Figures"1*'and 2i,th'e' fire box 5 is of conventional design 'havi'ng an'end wall 6 and a crown sheet 1 of conventional size and shape.

The lower portion of the fire box is enclosed'by a grate section 8 border'edby a Gaines'wall 9, 'while at its end oppositethe -end wall 6 a flue sheet i0 is disposedftoreceive'the gases of combustion*passir'1gout of the'fire' box 5. A throat sheet l 2'*of he usual type-is-positioned below-the flueshetlof'yI v'gv.

A siphonme ber l3 of the dual tube type extends from the throat sheet [2 into and through fire box 5, being supported from crown sheet I at its upper extremityandby the Gaines wall 9 and thr'oat sheet I at its lower extremity.

A n arch member esignated generally'by reference numral'flrand comprising an interconck Ma" supported on lugs '15 mounted on siphon tubes l3 and "side sheets fire box toobtain ajmore efficient distribution of "such gases.

A further object of the invention is'to provide a simple, economical and efficient meansfor rees of combustionin a fire box. 7 i Otherobjects residein novel details of construction, andnovel combinations and arrangements of parts, the details of which will be described in the course of the following description.

To afford a better understanding} of they invention, reference isfmade to the accompanying drawings illustrating typical embodiment's'of the invention. 1 In the drawings in the severalfviews ofwhich liker parts have been. designated similarly,

I ,Figure .71vv is a fragmentary, central section through the fire box of a locomotive :boiler, em-

bodying features of the present invention;

" Figure 2 isa section takenalong" the lines 2:-2,

Figure 1;"

' l6 extends from Gaines wall 9 at an inclination through'fire'boxifor a substantial distance and divides thefire box' into' upper and lower combustion zones designated A and B respectively.

The construction thusfar" described is conven-.

tional' in' locomotive boilers and comprises a part of the present invention, only 'to the' extent that such'pa'rts' are utilizedwith other features hereinaft'er to bedesc'rib'ed,

- To eliminate the detrimental effects of the uneven distribution of'the gases of combustion induced by the arrangement-of arch M, a deflector arch member designated by the referenc'e nu- :meral l1 lis-disposed in overhanging relation to the-upper end ofarch l4.

Arch I] is composed of a series of interconnected fire brick Ila supported'from siphons l3 and side sheets Hi'on lugs-I5. Preferablythe "arch l1 should be so shaped that its inner end is approximately on the line bisecting the'angle between the crown sheet I and archl4, while its outer end is curved to approximately conform to f the normal gas flow about arch I4.

Figure 3 a fragmentary, centra1 section through the fire box of a locomotive boiler, em-

In this form of theinvent-ion, the tiles I ia at the end of the arch l4 underhanging arch I! have their upper surfaces curved to substantially conform to the curvature of the under surface c'farch l1 and thus provide a passage l8 of sub- -'stantially'- uniform width. :It will be'observedby reference to Figure I that the deflector arch. overlaps arch l4'for about three-fourths the length of arch IT. This arrangement prevents the hot gases entering passage l8 from rising toward crown sheet 1 and directs them instead along linear courses against a substantial portion of the surface of flue sheet I0. At the same time other gases traveling through the space between deflector arch I! and crown sheet I also assiune a substantially linear component parallel to the surface of crown sheet I until they reach the surface of flue sheet I against which gases passing through passage I8 do not penetrate.

Referring to Figure 1, it Will be noted that 7 three zones have been designated in grate section 8. Gases of combustion rising from zone a: travel upwardly into the space between deflector arch I1 and crown sheet I. The gases rising from grate section y travel into passage I8, while the gases rising from section a flow directly to a passage I9 in Gaines wall 9. Preferably, the clearance between deflector arch- I7 and crown sheet I is sufilcient to provide a gas velocity somewhat less than the calculated gas velocity through passage I8. I

As a consequence of this arrangement, a uniform distribution of gases is attained with a close control of the velocity of such gases as well. The gases passing above deflector arch II are required to engage a smaller surface area on flue sheet I0 than the gases passing through passage I8, and by having the velocity of the gases in passage I8 somewhat in excess of the Velocity in said other zone, a uniform distribution results.

This arrangement prevents the development of excessively high velocities in the travel of the gases about the end of main arch I 4 by its division of such gases, forcing a substantial portion thereof to assume a downward component by reason of the shape and location of the under surface of deflector arch II before they have traveled any appreciable distance in the directionof flue sheet I0. As a consequence, cinder cutting of tubes and lines, superheater units, flue sheets and crown bolt, heads is substantially reduced and the engines steam much better, thus reducing fuel consumption and increasing boiler efficiency. Further, by utilizing substantially'the entire available space in the reverse movement of the gases, formation of a partial vacuum condition is eliminated and velocities are substantially reduced.

The form of the invention illustrated in Figures 3 and 4 employs the same principles of operation and is generally similar in structural arrangement to the form of the invention illustrated in Figure 1. To this end, the fire box 5 has the usual end Wall 6, crown sheet I, side sheets I6 and grate section 8, enclosed at one end by a flue sheet I0 under which is provided the usual throat sheet I2.

A dual type siphon member I3 is supported from crown sheet 1 at its upper end and from Gaines wall 9 and throat sheet I 2 at its lower end. A main arch I4 extends from Gaines wall 9 up-, wardly at an inclination and the fire bricks I4a of this arch are supported from siphons I3 and side sheets I 6 by supporting lugs I5 as clearly shown in Figure 4. Crown sheet I, end plate 6 and side sheets I6 are enclosed by an outer shell member 20 and defines therewith fluid-circulating passages into which the upper ends of siphon members I3 open, as indicated at 2I in Figure 4.

A deflector member I'I:c in this form of the invention is supported in overhanging relation to the upper end of main arch I4, and in length,

spacing and general arrangement is similar to 4 the arch I! of Figure 1. The essential difference between the arches I1 and I'Isc resides in the composition of the arch Ilzr. This member is a hollow metallic body having openings to its hollow interior 22 connecting with siphon tubes I3 and the outer enclosure formed by shell 20. A heat transfer fluid circulates through the siphon tubes I3 and hollow interior 22 of the arch member Ila: thereby preventing excessive heating of the surfaces of the deflector arch I Ix through contact with the gases of combustion.

In this form, the main arch I4 is not curved at its upper end adjoining passage I8a as in the form illustrated in Figure 1. However, the curvature of the under side of arch Ila: is sufficient to impart the necessary directional components to the gases in passage I8a, with the result that uniformity of gas distribution is attained in this form of the invention as well. However, the curvature of the main arch is a preferred feature as some excessive wear on the end fire'bricks of the arch may resultfrom the irregular shape of said end with reference to the direction of movement of gases into passage I8a.

From the foregoing, it will beapparent that in either of the forms illustrated, the gases rising from the grate section are distributed before they assume directional components toward flue sheet I0 and, as a consequence, the velocity and direction of said gases is under control throughout the entire course of their reverse flow toward flue sheet I0.

The control thus exercised afford even distribution of gases of combustion against the exposed surface of flue sheet I 0, resulting in higher boiler efiiciency and reduced wear due to cinder cutting and plugging of the flues.

It will be understood that either of the forms of deflector arches II or I'Ia: may be used with a main arch having either a curved end of the type shown in Figure 1, or a straight end of the type shown in Figure 3. I

In the foregoing description, the main arch has beenv shown in both forms as associated with a siphon structure. However, in certain types of fire boxes arch tubes are used as the supporting medium for the main arch, while in others circulator tubes are utilized to provide the intermediate support for the main arch. In all such arrangements, the arch is substantially the same in arrangement as the arches shown in Figures 1 and fland functions in an identical, manner to divide the fire boxes into upper andlower combustion zones.v

Consequently, where the term main arch has been used in the description and claims, it is meant to cover any form of main arch now in use in the fire boxes of locomotive boilers and the deflector arch of the present invention will be disposed above and in overhanging relation to the upper end of any such arch to divide the gases of combustion in their turning movement and thereby control velocity and direction of such gases.

Changes and modifications may be availed of Within the spirit and scope of theinvention as defined in the hereunto appended claims.

What I claim and desire to secure by Letters Patent is:

1. In a fire box having a lower grate section, a flue sheet at its rear end, a crown sheet forming an upper closure for the fire box, a main arch inclined upwardly and forwardly from a rearward point of support adjacent the flue sheet to divide the space between the gratesection and the crown sheet into-upper and lower combustion zones, the

upper end of said arch terminating in a curved portion of the divided gases directly to the flue portion, and a deflector arch supported in oversheet.

hanging relation to said main arch with a portion 4. In a fire box having a lower grate section, a e t nd g flrw y beyond the end of the main flue sheet at its rear end, a crown sheet forming arch to divide the gases of combustion rising fr m an upper closure for the fire box, a main arch in- Said rate section pri r t h i Passage between clined upwardly and forwardly from a rear point the main arch and the crown sheet, the underof Support adj t the flu Sheet and extending Side Of Said defieCtOr arch Substantially 0011- undulating arrangement laterally of fire centric with the curved surface of the main arch box to bridge the Same and divide its Space into to direct one portion of the divided gases direct upper and lower combustion zones, and a deflector ly to the flue sheet.

' arch supported in overhanging relation to said a 21 13 232 22 25; 22; fig fi gfij main arch with a portion extending forwardly be- S c n yond the end of the main arch to divide the gases tiltit?fifiiiiiiifiitiiifi5m??? sf,inte ratesse re ates pomt of Support adjacent the flue Sheet to dwlde crownsheet the surface of the deflector arch ggg i i g ggsg ggg 2:3 sgz g ggg i'gg nearest the main arch being arranged in. substanzones, the upper end of said arch terminating in a g fi' g i 5231 22 233:; g g z gisgtgxg curved portlon and a deflector arch of curved between said surfaces to travel at substantially section concentric with the curvature of the main arch Supported in overhanging relation to Said uniform velocity throughout the width of the fire main arch with a portion extending forwardly beyond the end of the main arch to divide the 5. In a fire box having a lower gra e Section, a gases of combustion rising from said grate section 95 flue Sheet t its real e a Crown Sheet forming prior to their passage between the main arch and an upper closure for the fire box, a main arch the crown sheet and directing the divided gases inclined upwardly and forwardly from arearward directly to the flue sheet. point of support adjacent the flue sheet to divide 3. In a fire box having a lower grate section, a the space between the grate section and the flue sheet at its rear end, a crown sheet forming crown sheet into upper and lower combustion an upper closure for the flre box, a main arch zones, the upper end of said arch terminating in inclined upwardly'and forwardly from a reara curved portion, siphon tubes extending longiward point of support adjacent the flue sheet to tudinally in said upper combustion zone, and a divide the space between the grate section and deflector arch comprising ahollow, fluid-containthe crown sheet into upper and lower combustion 35 ing body supported in overhanging relation to zones, the upper end of said arch terminating in said main arch with a portion extending fora, curved portion, and a deflector arch supported wardly beyond the end of the main arch to divide in overhanging relation to said main arch with the gases of combustion rising from said grate a portion extending forwardly beyond the end of section prior to their passage between the main the main arch to divide the gases of combustion 4n arch and the crown sheet, the hollow interior of rising from said grate section prior to their ipassaid deflector arch being in conductive connecsage between the main arch and the crown sheet, tion with said siphon tubes in the fire box for the upper and lower surfaces of said deflector circulating a heat-transfer liquid through the arch being substantially concentric with the deflector arch.

curved surface of the main arch to direct each WALTER B. LEAF.

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