US2112954A - Locomotive firebox - Google Patents

Description

A ril 5, 1938. G. J. CHRISTENS ON 2,112,954

LOCOMOTIVE FIREBOX Filed June 13, 1956 fizzy-W.- 4

Patented Apr. 5, 1938 UNITED STATES ATENT OFFICE Locomotive Firebox Company,

Chicago, 111.,

a corporation of Delaware Application June 13, 1936, Serial No. 85,064

8 Claims.

This invention relates to improvements in locomotive fireboxes and it consists of the matters hereinafter described and more particularly pointed out in the appended claims.

This invention is more particularly concerned with fireboxes equipped with a thermic syphon, of the type which is a substantially rigid water, steaming and circulating element that opens at its ends through certain sheets of the firebox at different elevations, for the purpose of increasing the effective heating surface area of the firebox whereby a better water steaming and circulating action is possible.

One of the objects of the present invention is to provide means in a syphon equipped firebox whereby additional water steaming and circulating efiiciency and a better support for the arch brick is obtained.

Another object of the invention is to provide a firebox of this kind, wherein water is taken from the front throat and at points along each side water leg and is discharged above the crown sheet at points therealong in a manner assuring a continuous flooding of the same with water, even though the water level in the boiler falls below normal.

A further object of the invention is to provide a tube arrangement in a locomotive type of firebox, which coacts with the syphon in forming a better support for the brick of the arch and at the same time employs longer tubes of a peculiar shape that gives them more flexibility to accommodate sheet movement.

The above mentioned objects of the invention as well as others, together with the advantages thereof, will more fully appear as the specification proceeds.

In the drawing:

Fig. l is a longitudinal vertical sectional View through a locomotive boiler embodying the preferred form of the invention.

Fig. 2 is a transverse vertical sectional View through the same as taken on the line 2-2 of Fig. 1.

Fig. 3 is another and fragmentary transverse vertical detail sectional View through a part of the firebox as taken on the line 3-45 of Fig. 1.

Referring now in detail to that embodiment of the invention illustrated in the accompanying drawing, 55 indicate the side sheets of the firebox, and 6 indicates the crown-sheet thereof. 1 indicates the front or flue sheet thereof and 8 indicates the back sheet thereof. It will be understood that the firebox is positioned in the rear end of the boiler shell, which includes the outer side sheets 9-9, top sheet I0, back sheet II and front throat sheet 12. Portions of the back sheets 8 and I 1 respectively are formed to provide a fuel door opening l3.

Several of the sheets mentioned coact to form the side water legs l4, back water leg I5 and front throat IS respectively, all bottomed by a mud ring ll. The above is typical of a conventional locomotive boiler rear end structure and requires no further description except to say that companion sheets are suitably stay-bolted.

The firebox herein shown is equippedwith a socalled thermic syphon I8 which is a substantially rigid but hollow Water steaming and circulating element having ends that open through certain sheets of the firebox at different elevations. When a plurality of such syphons are employed in the firebox, they are spaced laterally from each other.

In the present instance, only one syphon is employed and this is disposed in the longitudinal medianplane of the firebox. Such a syphon in this instance includes a substantially flat, triangularly shaped body l9 having an outwardly flared flange 2|! at the top that fits and is welded in a longitudinally extending elongated opening in the crown sheet. This body has an inclined bulged bottom 2! which extends downwardly and forwardly to terminate in a tubular inlet neck extension 22 that opens through the bottom portion of the front sheet I so as to communicate with the front throat H3. The body which is closed at its front and rear ends is suitably staybolted to resist internal pressures. t is apparent that the syphon presents a considerable surface area. In the operation of the boiler in which the syphon is installed, water is drawn in from the throat l6 and a part thereof is generated into steam, the steam and hot water being discharged into the boiler water and steam space of the boiler above the crown sheet. In this discharge of water, the same operates to flood the crown sheet. By reason of the difference in thermic heads, a vigorous water circulating action is established in the boiler.

The syphon described, substantially divides the firebox longitudinally into two laterally spaced combustion chambers or passages both of which communicate with the flues of the boiler. In each chamber or passage is a set of circulator tubes 23, each comprising a plurality. of longitudinally spaced tube elements, the elements in one set' on one side of the syphon being arranged in the transverse plane of the elfimfints of the other set.

Each tube element includes an inlet portion 24, an outlet portion 25 and intermediate connecting portion 25 of reverse curve formation on the order of an ogee or bulge. The inlet portion has an extremity 2'! arranged at a right angle to the plane of the associated side sheet. This extremity which extends at a right angle to the plane of the side sheet is fixed in said side sheet and merges into the inlet portion 24 by a short curved portion 28. The inlet portion 24 extends upwardly and inwardly from the curved portion 28 at an angle which corresponds to the angle of transverse inclination of one side of the arch which will be referred to later. The crown sheet 6 is arched or curved transversely of the firebox and the outlet portion 25 of the tube extends radially with respect thereto and opens through and is fixed in any suitable manner in said crown sheet.

As herein shown, the intermediate portion 26 of each tube element 23 comprises upper and lower reversed curved parts and the lower part is so disposed as to be spaced substantially close to the associated side of the syphon body. The tube elements in each set are of successively increasing heights, from the rear to the front of the firebox. This difierence in heights is such that a line extending between the points where the inlet portions of the tube elements in each set, open through the associated side sheet, is disposed in an inclined plane substantially conforming to the plane of inclination of the bulged bottom 22 of the syphon body and its neck extension.

The structure described is admirably adapted) to the support of an arch indicated as a whole as at 29 in Fig. 2. This arch is made of transverse rows of brick, each including an outer end brick 30, an inner end brick 3| and intermediate brick 32. The outer end and intermediate brick 3 and 32 are curved transversely of the plane of the respective row while the inner end brick is fiat. The outer end and intermediate brick each has a concaved corner to rest upon upper parts of the inlet portions of the tubes. The outer end of the outer brick in each row engages against the associated side sheet. The inner end of each inner end brick is cut away to permit it to pass the curved parts 26 of the tubes. Furthermore, the inner end of each inner end brick is formed with a shoulder to engage upon the body bottom bulge 2! and inlet neck 22, respectively.

In the outer side sheets 9 of the boiler in line with the inlet end extremity 21 of the various tube elements, are wash-out plugs 33 and in the top sheet it) of the boiler shell are wash-out plugs 34 in line with the outlet ends of the various circulator tube elements 23.

In the operation of the boiler of which the fixebox forms a part, the syphon operates to take in boiler water from the front throat and to discharge it out through its top end, thus keeping the crown sheet flooded with water. Also, due to the presence of the sets or banks of circulator tubes, water enters the inlet ends of the various tube elements at spaced points along each side water leg l4. Under the action of heat transfer from the products of combustion to the water in the tube elements 23, a part of the water is generated into steam to pass into the boiler above the water therein and the remainder of said water is discharged out through the outlet ends to assist the syphon in keeping the crown sheet flooded to increase the safety factor under low water conditions.

As water is taken into the various tube elements 23 from longitudinal spaced points in each water leg, a continuous and vigorous circulation is established in the side water legs which washes the water side of the sheets clean of any solids tending to adhere thereto. Also due to the turbulence set up by the circulating action, the solids remain in suspension and cannot readily settle out to accumulate as a mud upon the mud ring which bottoms the various water legs.

By reason of the circulation thus produced through the side Water legs, the expansion and contraction stresses in the firebox sheets are equalized and the life of the same is greatly increased.

The tube elements 23 are preferably made of seamless tubing and may be readily bent to shape. As the curves therein are of a relatively large radius, the danger of cracking in shaping the tubes is avoided. Also, such curves permit a ready wash-out of the tubes.

Cross reference is hereby made to applicants co-pending application S. N. 85,063 which claims certain of the subject matter herein disclosed, but not claimed herein.

While in describing the invention, I have referred in detail to the form, arrangement and construction of the parts thereof, this is to be considered only in the illustrative sense so that I do not wish to be limited thereto except as may be specifically set forth in the appended claims.

I claim as my invention:

1. A locomotive firebox embodying therein a crown sheet, a front sheet and side sheets, a substantially rigid water steaming and circulating element in the firebox having ends which open through certain of the sheets of the firebox at different elevations, and a circulator tube arranged on each side of said element and extending transversely of the fire box, each tube including an inlet portion opening through an associated side sheet and an outlet portion opening through the crown sheet and a reversely curved intermediate portion connecting said inlet and outlet portions, said reversely curved portions being arranged relatively close to the sides of said element and being spaced closer together than the outlet portions of both tubes where they open through the crown sheet.

2. A locomotive firebox embodying therein a crown sheet, a front throat and side sheets, a substantially rigid water steaming and circulating element in the median plane of the firebox having ends which open through certain of the sheets of the firebox at difierent elevations, sets of circulator tubes in and arranged transversely of the firebox, with one set arranged on each side of the water steaming and circulating element and each set comprising a plurality of tube elements arranged in transverse planes, spaced longitudinally of the firebox, each tube comprising an inlet portion opening through an associated side sheet and an outlet portion opening through the crown sheet and a reversely curved intermediate portion connecting said inlet and outlet portions, the reversely curved portions of the tubes in each set being arranged substantially close to the sides of said element, said last mentioned portions of the tubes in both sets being spaced closer together than the outlet portions of the tubes in both sets where they open through the crown sheet.

3. A locomotive firebox embodying therein a crown sheet, a front sheet and side sheets, a substantially rigid water steaming and circulating element in the median plane of the firebox having ends which open through certain of the sheets of the firebox at different elevations, sets of circulator tubes in the firebox, with one set arranged on each side of the water steaming and circulating element and each set comprising a plurality of tube elements arranged in transverse planes spaced longitudinally of the firebox, each tube comprising an inlet portion opening through an associated side sheet and an outlet portion opening through the crown sheet and a curved intermediate portion connecting said inlet and outlet portions, and a fire arch composed of brick supported in part by said water steaming and circulating element and in part by said circulator tubes.

4. A locomotive firebox embodying therein a crown sheet, a front sheet and side sheets, a substantially rigid water steaming and circulating element in the median plane of the firebox having ends which open through certain of the sheets of the firebox at different elevations, sets of circulator tubes in the firebox, with one set arranged on each side of the water steaming and circulating element and each set comprising a plurality of tube elements arranged in transverse planes spaced longitudinally of the firebox, each tube comprising an inlet portion opening through an associated side sheet and an outlet portion opening through the crown sheet and a curved intermediate portion connecting said inlet and outlet portions, and transverse rows of fire brick between and supported at least in part on the inlet portions of adjacent tube elements in each set and closing the space between the sides of said water steaming and circulating element and the respective side sheets.

5. A locomotive firebox embodying therein a crown sheet, a front sheet and side sheets, a substantially rigid water steaming and circulating element arranged longitudinally of the firebox and having ends which open through certain of the sheets of the firebox at different elevations, a. set of circulator tubes arranged in and extending transversely of the firebox on each side of the water steaming and circulating element, each set of tubes comprising a plurality of tube elements arranged in transverse planes spaced longitudinally of the firebox, each tube comprising an inlet portion opening through the side sheets, an outlet portion opening through the crown sheet and a reversely curved intermediate portion connecting said inlet and outlet portions, and means providing arch portions between both sides of said element and said side sheets, said arch portions comprising bricks, certain ones of which are supported solely upon said inlet portions of said tubes and others of which are supported jointly upon said inlet portions and upon portions of said element.

6. A locomotive firebox embodying therein a crown sheet, a front sheet and side sheets, a water steaming and circulating element in the firebox and including a flat hollow body arranged longitudinally of the firebox and opening through the crown sheet, said body having a downwardly and forwardly inclined bulged bottom that merges into a tubular neck which opens through the throat sheet of the firebox, a set of circulator tubes arranged in and extending transversely of the firebox on each side of the water steaming and circulating element, each set comprising a plurality of tube elements arranged in transverse planes spaced longitudinally of the firebox, each tube including an inlet portion, the inlet portions of all the tubes in each set opening through the associated side sheet in a plane substantially corresponding to the plane of the inclination of the bottom of the said body and its neck extension, each tube further including an outlet portion opening through the crown sheet and a reversely curved intermediate portion connecting said inlet and outlet portions, and means providing arch portions between both sides of said elements and said side sheets, said arch portions comprising bricks, certain ones of which are supported solely upon said inlet portions of the tubes and others of which are supported jointly upon said inlet portions of said tubes and upon portions of said element.

7. A locomotive firebox embodying therein a crown sheet, a front sheet and side sheets, a water steaming and circulating element in the firebox and including a fiat hollow body arranged longitudinally of the firebox and opening through the crown sheet, said body having a downwardly and forwardly inclined bulged bottom that merges into a tubular neck which opens through the throat sheet of the firebox, a set of circulator tubes arranged in the firebox on each side of the water steaming and circulating element, each set comprising a plurality of tube elements arranged in transverse planes spaced longitudinally of the firebox, each tube including an inlet portion, the inlet portions of all the tubes in each set opening through the associated side sheet in a plane substantially corresponding to the plane of the inclination of the bottom of the said body and its neck extension, each tube further including an outlet portion opening through the crown sheet and a curved intermediate portion connecting said inlet, and transverse rows of fire brick between the inlet portions of adjacent tube elements in each set, the outer end of the brick in each row engaging an associated side sheet and the inner end of the brick in certain of the rows engaging the bottom bulge of the body and the inner end of the brick in certain other rows engaging upon the neck extension.

8. A locomotive firebox embodying therein a crown sheet, a front sheet and side sheets, a water steaming and circulating element in the firebox and including a fiat hollow body arranged longitudinally of the firebox and. opening through the crown sheet, said body having a downwardly and forwardly inclined bulged bottom that merges into a tubular neck which opens through the throat sheet of the firebox, a set of circulator tubes arranged in the firebox on each side of the water steaming and circulating element, each set comprising a plurality of tube elements arranged in transverse planes spaced longitudinally of the firebox, each tube including an inlet portion, the inlet portions of all the tubes in each set opening through the associated side sheet in a plane substantially corresponding to the plane of the inclination of the bottom of the said body and its neck extension, each tube further including an outlet portion opening through the crown sheet and a reversely curved intermediate portion connecting said inlet and outlet portions, and transverse rows of fire brick between the inlet portions of adjacent tube elements and extending from said body to the respective side sheets.

GUST J. CHRISTENSQN.

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