US1229392A - Arch construction for shallow fire-boxes. - Google Patents

Description

1,'P. NEFF. ARCH CONSTRUCTION FOR SHALLOW FIRE BOXES; APPLICATION HLED FEB. 24. I9l6.

Patented June 12, 1917. A

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J. P. NEFF. ARCH CQNSTRUCTION FOR Sl-MLLOW FIRE BOXES.

' APPIJCATION mkn FEB. 24, mm. 1 4,229,392. 1 Patented June 12, 1917.

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1. P. "N EF-F. ARCH CONSTRUCTION FDR SHALLOW FIRE BOXES. I I 7 APPLICATION FILED FEB. 24, I916- 1,229,392, Patented June 12, L917.

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UNITED STATESPATENT OFFICE.

'JOHN P. NEFF, or EAST ORANGE, NEW JERSEY, ASSIGNOR 'ro AMERIoAn ARCH M- PANY, or NEW YORK, N. Y., A CORPORATION or DELAWARE.

ARCH consrnuo'rronron sH LL'ow FIRE-BOXES.

Application filed February 24, 1916.

To all whom it may concern:

Be it known that I, JOHN P. NEFF, a citi Zen ofthe United States, and a resident of East Orange, county of Essex, and State of New Jersey, have invented certain new and useful Improvements in and'for Arch Construction for Shallow Fire-Boxes, of which the following is a specification.

My invention relates to improvements in the arches of locomotive boilers of the shallow firebox type, and has special reference to arch constructions for the fireboxes of WVooten boilers which have firebox extensions or barrel combustion chambers forward of the grate.

The firebox of a \Vooten t y e'hoiler (lit-- fers from others chiefly inthe matter of its height. The distance between the grate and the crown sheet is much less than in locomotive fircboxes of other types. The reason of this peculiarity is that \Vooten fireboxcs are designed for use with anthracite coal a fuel which yields a verysl'iort flame, as compared with others, and which therefore neeessitates the arrangement of the chief heating surface (the crown sheet) close to the fuel bed. The height of the firebox ex tension, sometimes called the barrel oombnstion chamher,is determined by theheight of the crown sheet as in other fireboxes. An-

other characteristic of a Wooten firebox is that the grate is placed almost on a level with the floor of the extension.

It is claimed for the Wooten typefirebox that by reason of its low height there is a substantially equal distribution of the hot gases in the fines of the boiler; and that this and the attendant easy ma'intenance of the fines and the flue sheet. are advantages se- 40 cured without material loss of heating value in the walls of the firehox. inasmueh as the latter are close to the fuel bed. Against the attendant advantages of such fireboxes, I find that the flow of hot gases from grate to fines is so rapid and direct that the rear part of a Wooten firebox is much less effective than supposed.

7 It has been suggested that a cure may he efiected by providing Wooten fireboxes with inclined refractory arches of the kind used in bituminous coal-burning locomotives but in the past there have been no practical means of installing such arches in Wooten I fireboxes. The narrowness or lack of depth in the throat sheets of such boilers has prac- Specification of Letters Patent.

Patented June 12, 1917.

Serial No. 80,311.

tically prohibited the use of arch tubes and, on the other'hand, the width of such firehoxes has prevented the use of arches supported from the side sheets. i

The object of my invention is to provide within a Wooten type firebox a refractory tube-supported arch which shall perform the same desirable functions as those which are 'used in bituminous coal-burning fire,- boxes.

The manner in which I attain this ole-- ject, and the nature and particulars of my invention, will be understood on reference I to the drawings that form part-of this specilieation, and in \vhieh:-.Figure 1 is a longitudinal section of a \Vdoten type locomotive boiler embodying my invention ;.Fig.

2 is a transverse section thereof on the line X'Xot' Fig. 1; Fig 3 is a horizontal section on. the line Z-Z of Fig. 1;-Fig. l is a,perspectivc detail illustrating the noninterfering intersection portions of two of the transverse arch tubes;--lig. 5 is a longitudinal section showing a modification of my iu\'ent-ion:-l ig. (l is a Section on the line lV-lV of Fig- 5 and, Fig. 7 is a section on the line V-V of Fig. 5.

The familiar parts of a Wooten type firebox are asfollows: -The boiler-barrel 2; the firebox shell, 3 ;-the mud ring, l;the. side sheets, 5;-thc crown sheet, 6;the rear sheet. 7;.side water legs, 8, 8;-the' rear water legs. 9;,-the fuel door. 10:,-and

.iune'r throat sheet, 11':-the shallow front water leg. or throat, 12;the flue'sheet,

1?); and. the tines. 14. The grate, 15, usually occupies the whole space Within the confines of the mud ring, extending from side to side of the firebox and from the rear sheet, 7. to the throat sheet, 11. The fii-eboyextension or barrel combustion chamber. B, is all that part of the firebox between the flue sheet, 14, and the throat ,sheet, 11. v The floor. 16,'and sides, 16, of

the extension, B,,join the extension, 6', of the crown sheet which forms the top of the extension.

It will be noted that a Wooten firebox is of mllchless height than width. Instead of attempting to employ a refractory arch extending upwardly and rearwardly from the lower part of the throat sheet, 11, I first diride the firebox into fire and combustion chambers by means of a refractory cross .wall, 17, in the mouth of the firebox-exten- '30 ment of 40 tubes in now well- 50 bends, the tubes are 5 on said tubes. The wall, 17, may rise to the center of the combustion chamber, B, or even f higherif desired. This wallwill be described in detail hereinafter. It serves to partly sepmate the Combustion chamber from the firebox. But this amount of separation is not Isuliicient to insure the best results. Such rej sults can onlybe attained through the employment of a large mass of refractory bucks in the form of an arch which extends rearlfi 'wardly from the wall, 17, and overhangs the grate of the firebox. Most conveniently,

the mam is composed of a large number of refractory bricks, 19, all of a sue to be passed through the fuel door, 10.

Primarily, I arrange the refre ctory bricks, 19, in rows which extend transversely across the upper part of the firebox. These transverse rows are preferably separate from one another to the extent necessary to prevent the fusing together of the ends of the bricks. The arch measured rearwardly from the wall, 17, may be of any desired length. As a rule, four transverse rows of bricks make an arch of sufficient length to insure the movethe firebox gases rearwardly and thence forwardly upon the crown sheet, as

' required to overcome theobjectionable features of an open Wooten firebox.

For supporting the transverse rows of.

36 bricks, I employ a plurality, of the transverse arch tubes, 18. The upper portions of these arch tubes provide seats or bearings for the ends of the bricks, 19. The ends of the bricks are preferablysocketed to fit the own manner. The tubes, 18, occupy parallel vertical planes. They are arranged in intersecting pairs and are spaced apart, as required, to admit the spans or bricks, 19. The tubes of each pair 4 5 preferably'occupy the, same vertical plane, this arrangement being made possible by the non-interfering intersection portions or lateral bends, 18, in one or both tubes, as shown best in Fig. 4. By means of the bend, or

ermitted to pass one another without inter erence and the upper portions, 18", are allowed to occupy the same vertical plane; in other words, may be arranged in alinementcrosswise of the fire- As'clearly shown in- Fig. 2, the tubes, 18, connect opposite side water legs, 8, 8, of the boiler; and toinsure the rapid circulation of the water through the arch tubes, as re- 80 quired to preserve them each tube is inclined. Thus each tube is secured at a low point, 20, in one side sheet, 5, and rises to a high point, 21, in the opposite side sheet. Short bends, 18?, formed in the ends of the tubes 6 allow them to perpendiculally enter respective side sheets. The clearance between the grate and the lower portions of the tubes is preferably increased by an upward bend, 18 in each tube. The tops, 18", of the several tubes are preferably straight, as that orm provides the best seats for the firebricks, 19.

The bricks, 19, are of a single pattern, that is, they are all alike. In constructing the arch, I first place the bricks upon the tubes and against the side sheets, 5, and then add other bricks toward the middle line of the fire box. side sheets are-thus insured, and a tolerance space, 22, remains between the sides of the middle pair of bricks in each transverse row. Thrse tolerance spaces may be left open without objection, or closed; as by means of V-shaped gap-bricks, 23.

have not; attempted to show the component bricks-of the wall, 17. I prefer that the wall shall always contain a clean-out opening, 17, through which the combustion chamber, B, may be reached.

The wall has one special characteristic which is novel. I refer to the form of the top of the wall, best shown in Fig. 1. Said top is provided with a middle top-portion, l7, and symmetrical bearing portions, 17, which take their shape from the shape of the ends of the-bricks, 19, that abut thereon. In this manner the wall is made to serve as an abutment and a bearing for the bricks composing the front row of the arch.

While I prefer the construction illustrated in Figs. 1 to 4, I nevertheless desire that it shall be understood that my invention comprehends an arrangement in which the arch tubes do not contain the n0n-interfering bends, 18'. The modification referred to is disclosed in Figs. 5, 6, and 7; from which it will be seen that by staggering the transverse tubes, 24, they may still be made to accommodate transverse rows of arch bricks, 25. But in this, one row of short bricks, 26, must be employed. Except in this short row, all of the other bricks may be the same throughout the arch.

To those who are skilled in the art it will be apparent that by means of the construction here shown and described, shallow lo- Close joints with the comotive fireboxes may be successfully fitted with baffle walls which are quite as effective as the simpler corresponding constructions generally used in deep bituminous coalburninglocomotive furnaces. While the construction described 1s adapted for use in barrel combustion chamber fireboxes of many different tvpcs. it unquestionably atrams its greatest utility in fireboxes of the l. The improvement herein described,

/ tion with a cross wall therein rearward of its flue sheet and forward of its grate, and

an overhanging arch extending rearwardly from said Wall and composed of a plurality of transverse rows of bricks together with a plurality of longitudinally spaced pairs of oppositely inclined transverse water-circulating arch tubes which connect the side sheets of the firebox and support said bricks.

2. The improvement herein described,

comprising a locomotive firebox, in combinatlon with a cross wall therein rearward 0f its flue sheet and forward of its grate, and

an overhanging arch extending rearwardly from said wall and composed ofa plurality of transverse rows of bricks together with a plurality of longitudinally spaced pairs of oppositely inclined transverse water-circu latin arch tubes which connect the side sheets of the firebox and support said bricks, the tubes of each said pair being in a single vertical plane and ofiset at the middle to avoid the intersection of one by the other.

In testimony whereof, I have hereunto set my hand this 9 day of February, 1916. JOHN P. NEFF.

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