US1315252A - Furnace - Google Patents

Description

A. L. STEVENS.

" FuRNAcl-z.

APPLICATION FILED JUNE 26,1916.

1,315,252. Pamdsept. 9,1919.

5 SHEETS-SHEET 1.

A. L. STEVENS.

FuRNAE. APPUCATION FILED IUNE 26.1916.

Patented sept. 9, 1919'.

5 SHEETS- SHEET 2 YA Arron/5v5 A. L. STEVENS.

` y FURNAGE. APPLICATION FILED IuNE 25.1916.

1 ,3 1 5 ,25 2 Patented Sept. 9, 1919.

5 SHEETS-SHEET 3.

INVENTO/ A TTORNEY J A. L. STEVENS.

FURNACE.

APPLlcAloN FILED JUNE 26.1916.

PatentedSept. 9,1919.

5 SHEETS-SHEET 4.

' /NVENT/i m4 BY fama/L A. L. STEVENS. FURNACE.

APPLICATION FILED JUNE 26.1916.

Patented Sept. 9, 1919.

5 SHEETS-SHEET 5.

A TTOR/VEY ABTHURL. STEVENS, 0F CHICAGO, ILLINOIS.

FURNACE.

Specicatio'n of Letters Patent.

Patented Sept. 9, 1919.`

Application filed .Tullel 26. 191.6. Serial No. 105,895;

To` all whom it may concern Be it known that I, ARTHUR L. STEVENS,

a citizen of the United States, residin at Chicago, in the county of Cook and tate i Vf Illinois, have invented certain new and useful Improvements in Furnaces, of which the following is a specification.

My invention relatesy to the construction of a furnace having a relatively long,l narrow combustion chamber and hearth, such,

for example, as a drag furnace employed fory heatingy metal rods, bars, or the like.

The principal object of the invention is to provide a furnace of this character operating on the regenerative principle so designed and constructed as to insure uniform and` high temperature in the combustion chamber for the full length thereof with economy of fuel.

A further object is to provide a furnace of this type which will be relatively small .and compact in its structure, which will be inexpensive to build, and in .which the cost of maintenance and repairswill be reduced to a minimum. The furnaceof my invention is intended particularly for fluid fuel and is` especially adapted for burning a lean producer gas.

A furnace constructed in accordance with the invention and having these desirable features is shown in the accompanying drawings. The invention, however, is not to be understood as narrowly limited to this preferred embodiment as the structural details of the furnace are susceptible of modification to a considerable extent without departure from the principles of the invention lwhich I desire to cover as broadly as the state of the art will warrant without re ard .to matters of specific constructlon which wlll necessarily vary in the particular installation according to the service required of the furnace. In the drawings Figure 1 is a lan view of the furnace.

Fig. 2 is a si e elevation thereof.

Fig. 3 is a sectional plan on an enlarged scale.

Fig. 4 is a sectional view online 4--4 of Fig. 5, illustrating the construction of one of the reversing valves for the fuel and lair supply pipes.

Fig. 5 is a sectional View on llne 5 -5 of Fig. 4.

Fig. 6 is a longitudinal, vertical sectional view through the furnace.

, vention solves the difficulty by Fig, 7 is a cross sectional view on line of F 6. Flg. 8` is a cross sectional view on line A8--8f of Fig. 6, and

Fig. 9` is a fragmentary, diagrammatic View of the furnace, in perspective, with parts in section, to illustrate lparticularly the flow of the gases through the combustion chamber, ducts and regenerators.

Like characters of reference desi ate like parts in the several ligures of the rawings.

The furnace structure, which consists preferably of brickwork 10 covered by side sheathing plates 1'1 and top plates 12 of metal, is supported on metal bottom plates 13, 14, carried by angle irons 15 and I-beams 16 which are, in turn, supported on the transverse beams 17 secured to legs 18.V These are matters of constructional detail and may be varied as occasion demands.

The furnace shown for the purpose of illustrating the principles of my invention is a drag furnace having a long, relatively narrow combustion chamber 19. The furnace is intended for heating metal rods,

bars, or the like, which are drawnl throughV the furnace `from end to end across hearth 2t). The bars are introduced into the furnace through opening 21 at one end which is preferably provided with a door 22 and are withdrawn from the furnace through `opening 23 at the other end of the hearth. The length of the hearth and its narrowness, in a furnace of this type, makes it diiiicult to obtain uniform heating of the combustion chamber with economy of fuel. If the flames are made to pass lengthwise through the furnace from one end to the other, the temperature at the end adjacent the source of heat is higher than the temperature at.

the other end. The hearth is too narrow to make it feasible to pass the flames directly across the hearth from side to side; and such construction would be uneconomical as it would be impossible to mobtain a hightemperature and complete combustion. My in`' dividing the' combustion chamber into lengths, as it were', and heating the lengths separately. Moreover, I provide an arrangement of the regeneratorfs, `el burners, air.l and discharge ducts and discharge ports for the regenerators whereby it is ossible to obtain a com- 4'plete combustion o a cold gas and the maintenance of a high temperature inthe comthe furnace.

bustion chamber with a relatively low telnperature in the outflowing gases, all of which results in economy of fuel and maintenance cost.

VThe furnace is provided with a plurality of regenerators A, B, C, D which are arranged above the combustion chamber, each regenerator being substantially the Width of The regenerators are separated by walls 24, 25, 26, supported Von arches 27.

Associated With'each of the regenerators A, B, C and D are sets of angular ducts 28, 28", 28", 28". The ducts 28a, 28 open into the combustion chamber from one side thereof and the ducts 28", 28l open into the chamber from the other side of the furnace. 29 is a fuel supply pipe and 30 is a branch pipe, one end of which leads to a pipe 31 extending along one side of the furnace. The other end leads across the furnace to a pipe 32 extending along the other side thereof. The pipes 31, 32 are provided with a plurality of burners 33, one for each of the ducts 28a, 28", 28, 28d. Air under pressure is supplied to the furnace through the regenerators from air supply pipe 34 which may be connected with any suitable fan or compressor (not shown). The supply pipe 34 is connected by means of pipe' 35 to branch pipes 36, 37, extending over the furnace on opposite sides thereof. One extremity 38 of pipe 36 extends into a channel 36a in the side Wall opening into a duct 39 in the end wall 40 of the furnace adjacent regenerator A, which duct communicates by port 41 with said regenerator. The extremity 42 of the pipe 36 extends into a channel 42 in the side wall opening into a duct 43 in the partition Wall 25 between regenerators B and C, this duct communieating by means of port 44 with regenerator C. One extremity 45 of pipe 37 extends into a channel 45" Which opens into the duct 46 in the partition wall 24 between regenerators A and B. This duct communicates by port 47 with regenerator B. The other extremity 48 of pipe 37 extends into a channel` 48a opening into duct 49 formed in partition wall 26 between regenerators C and D, this ductcommunicating by port 50 with regenerator D. The regenerators A, B, C and D exhaust directly to the atmosphere through exhaust ports 51a, 51", 51c and 51d, respectively, the exhaust ports opening from the ducts 39, 46,43, 49, just described. i

I The exhaust ports are controlled by slide valves 52 preferably attached to one of a pair of links 53, 53 which are pivoted to cranks 55 rigidly secured to shafts 56 at opposite ends of the furnace, one of these llliaft; being revoluble by means of a han- Interposed between the fuel supply pipe 29 and the extremities of pipe 30 leading to pipes 31 and 32, respectively, is a valve E adapted to direct the fuel to the burners on either side of the furnace, at the same time shutting it off from the burners on the other side. A similar valve F is interposed between the air supply pipe 34 and the extremities of pipe 35 leading to air pipes 36, 37 on opposite sides o f the furnace.

The valves E and F may be identical and the preferred construction thereof is shown in Figs. 4 and 5. 58 is a casing formed with a neck 59 for attachment to the supply pipe 29 or 34 as the case may be. The casing is formed with openings at each end in which are fitted spiders' 60'forming valve seats and providing bearings 61 for the stems 62 of a double valve member 63 adaptJ ed to be reciprocated by finger 64 which enters a slot 65 in the-valve member and is secured to ashaft 66 which emerges from the valve casing through a gland 67. 1The shaft 66 is common to both valves E and F. It is rocked by means of an arm 68 rigidly secured thereto, connected by a link (39 with the lever 57, which, as above described, serves to shift the slide valves controlling the exhaust ports from the regenerators.

Operation: The furnace is firedrst from one side and then from the other, the air introduced with the fuel being heated, in each case, by passing through regenerators throu h which the products of combustion have een discharged prior to the reversal of the valves. The drawings show the fuel and gas as entering the portions of the combustion chamber under regenerators B and D and the products of combustion as being discharged from the combustion chamber on the opposite side thereof through the ducts communicating with portions of the combustion chamber under regenerators A and C. Gas valve E is in position to admit gas to the pipe 31 shutting the gas olf from gas pipe 32 on the opposite side of the furnace. Air valve F is in 4position to admit air to pipe 37 and to close air pipe 36. The air, which is supplied under pressure sufiicient to maintain the proper temperature in the combustion chamber, passes from pipe 37 into d'uct 46 (see Fig. 9) through port .47 into regenerator B, thence through the angular ducts 28" into the combustion chamber. A gas burner 33 leads into each of the ducts 28" and the gas is thoroughly mixed with the heated air when it enters the combustion chamber. The provision of a plurality of ducts for the regenerator and a plurality of gas burners prevents the stratification of the fuel and insures proper mixture thereof with the air. The flame in the combustion space below regenerator B divides and passes in opposite. directions lengthwise of the furnace. as indicated by the arrows in Fig. 3. lart passes ramena into the con'rbustion space under regenerator A. and is discharged through ducts 28a into the regenerator A, from which the products of combustion are discharged directly to the atmosphere through the discharge ports 51a which are open (Fig. l). rlhe dames and products of combustion traveling in: the other direction pass into the combustion space below regenerator C and are discharged through ducts 28, regenerator C and exhaust ports 51e. Air and gas at the saine time are introduced into the combusltion space under regenerator D through ducts 28d. 'llhe products of combustion pass lengthwise of the combustion space .under regenerator ll) into the combustion space under regenerator C and are discharged through ducts 28 and regenerator C. lin this manner the entire combustion chamber is uniformly heated in sections. At the same time the dames are allowed to travel far enough -lengthwise of the relatively narrow combustion chamber so that the combustion is complete. By a proper proportioning. ofthe outlet ports 51a, 5l.c and proper regulation of the air pressure in the air supply pipes, depending upon the service for which the furnace is intended, it is possible to discharge the gases of combustion directly to the atmosphere, without the employment of stack draft and at a relatively low temperature, and to maintain -a neutral. or even a slightly reducing flame of very high temperature in the combustion chamber by producing in the combustion. chamber a pressure justa trifle above atmospheric pressure sufficient to prevent the inflow of air through the working openings at opposite ends of the furnace, which, during the operation of the furnace, must necessarily be open at least to a considerable extent. 'llhe fuel preferably is not heated. lit is possible to use a lean, cold producer gas which is relatively cheap and which may be cleaned before it is introduced into the furnace. This circumstance, and the fact that the gases are discharged at a relatively low temperature, besides ermitting economy of fuel, makes it possible to simplify the construction of the furnace and to minimize cost of maintenance. The piping of the furnace may be made relatively small. The valves need not be water cooled. The size of the regenerators may be reduced to a minimum. The regenerators and other parts of the furnace do not require cleaning.

furnace having these general characteristicsl is described and claimed in my copending application Serial No.l 953-199V filed May 19', 1916. and is not genericallyclaimed herein. The invention of the'present application relates more particularlv to the application of these principles of furnace construction to a drag furnace or other furlill nace in which there is a long and relatively narrow combustion chamber requiring the maintenance of a uniform and high temperature. A

By reversing the valves the furnace may be fired from the other'side, in which case the fuel and air enters the combustion chamber at points under regenerators A and C and the lproducts of combustion are discharged through regenerators B and. D.

The arrangement of the regenerators tandem above the combustion chamber gives the furnace structure very desirable compactness and accessibility in the event that repairs have to be made.,

l claim': v

1. A furnace having a relatively long, narrow combustion chamber, provided on one side with inlet ports for the introduction of air and fuel at a plurality o-f points remote from each other, and provided on the other side with outlet ports at a corresponding number of points remote from each other and in staggered relation with the said inlet ports, whereby the chamber is heated in lengths byy a plurality of separately induced currents of gas in combustion.

2. A furnace comprising a relatively long, narrow combustion chamber, provided on one side with inlet ports for the introduction of air and fuel at a plurality of points remote from each other, and provided on the other side with outlet ports at a corresponding number of points remote from each other and in staggered relation with the said inlet ports, whereby the chamber is heated in lengths bya plurality of separately induced currents of gas in combustion, and a plurality of regenerators a-rranged longitudinally of the furnace above the combustion chamber which alternately receive air and discharge the products of combustion.

3. rllhe combination with a furnace structure havingl a relatively long7 narrow combustion chamber, of means for introducing fuel and air into the combustion chamber from one sideftl-iereof, means for discharging the 4productsof the combustion of the fuel thusfint'roduced at a `place diagonally remote from the place of introduction of the fuel and air, and regenerators arranged' longitudinally of the combustion cli-am ier through which the incoming air and outgoing products of combustion pass.

4. The combination with a furnace structure of the reversible regenerative type having al relatively long. narrow combustion chamber, of means for introducing fuel and air into said combustion chamber at a plurality of places disposed lengthwise of said chamber, means for discharging the products of the combustion of said fuel at a plurality of places diagonally remote from the places of introduction of the fuel and air, and regenerators arranged longltudifill atA

lllll nally of the combustion chamber through which the incoming air and outgoing products of combustion pass.

5. The combination with a furnace structure having a relatively long, narrow combustion chamber, of means for introducing fuel and air into said combustion chamber at a p-lurality of placesv disposed lengthwise of said chamber, means for discharging the products of combustion at a plurality of places on the other side of the furnace longitudinally remote from the places of introduction of the fuel and air, and regenerators arranged in alternate sets extending longitudinally of the combustion chamber through which the incoming air and outgoing products of combustion pass.

6. The combination with a furnace structure having a relatively long, narrow combustion chamber, of means for introducing fuel andv air into the combustion chamber from one side thereof, means for discharging the products of combustion from the other side thereof at a place diagonally re- -mote from the place of introduction of the fuel and air, and a plurality of regenerators arranged longitudinally of the furnace above the combustion chamber which alternately receive air and discharge the products of combustion.

7. The combination with a furnace structure having a relatively long, narrow combustion chamber, of means for introducing fuel and air into the combustion chamber from one side thereof, means for discharging the products of combustion from the other side thereof at a place longitudinally remote from the place of introduction of the fuel and air, and pairs of regenerators comprising a plurality of regenerator sections arranged in tandem longitudinally of the furnace above the combustion chamber through which the incoming air and out going products of combustion pass in alternation, each regenerator being substantially as wide as the combustion chamber.

' 8. The combination with a furnace structure having a relatively long, narrow combustion chamber, of means for introducing fuel and air into said combustion chamber at a plurality of places disposed lengthwise of lsaid chamber, means for discharging the products of combustion at a plurality of places on the other side of the furnace longitudinally remote from the places of introduction of the fuel and*4 air, and a plurality of regenerators arranged longitudinally of the furnace above the combustion chamber which alternately receive air and discharge the products of combustion.

9. The combination with a furnace structure having a relatively long, narrow combustion chamber, of means for introducing fuel and air into said combustion chamber at a plurality of places disposed lengthwise of tion chamber.

10. A furnace comprising a relatively long, narrow combustion chamber, ducts on opposite sides thereof in staggered relation for the introduction of air and discharge of products ofl combustion,- fuel burners arranged in said ducts and reversing valves whereby the air and fuel may be introduced into the combustion chamber on either side and the products of combustion discharged on the opposite side.

11. A furnace comprising a relatively long, narrow combustion chamber, ducts on opposite vsides thereof in staggered relation for the. introduction of air and discharge of products of combustion, fuel burners arranged in said ducts, two sets of regenerators communicating with the ducts on opposite sides of the furnace respectively, and reversing valves whereby the air may be introduced into the combustion chamber through either set of regenerators and the products of combustion discharged therefrom through the other set of regenerators.

12. A 'furnace comprising a relatively long, narrow combustion chamber, ducts on opposite sides thereof in staggered relation for the introduction of air and discharge of products of combustion, fuel burners arranged in said ducts, two sets of regenerators communicating with the ducts and arranged in alternation lengthwise and above the combustion chamber, and reversing valves whereby the air may be introduced into the combustion chamber through either set of regenerators and the products of combustion discharged therefrom through the other set of regenerators.

13. A furnace comprising a relatively long, narrow combustion chamber, ducts on opposite sides thereof in staggered relation for the introduction of air and discharge of products of combustion, fuel burners arranged in said ducts, two'sets of regenerators communicating with the ducts on opposite sides of the furnace, respectively, provided with discharge ports opening directly to the atmosphere and arranged above the combustion chamber, air pipes for introducing air under pressure into the regenerators, and reversing valves whereby the air may be introduced into the furnace through either' set of regenerators and the products release of combustion discharged therefrom through the other set of regenerators.

lll. A furnace comprising a relatively long, narrow combustion chamber, ducts on opposite sides thereof in staggered relation o for the introduction of air and discharge of products of combustion, fuel burners ar- .lli

generators, and reversing valves 'whereby' the air may be introduced into the furnace through either set yof regenerators and the products of combustion discharged theretitl from through the other set vof regenerators.

15. A furnace comprising a relatively long, narrow combustion chamber, ducts on opposite sides thereof in stag ered relation for the introduction of air an discharge of4 productsoof combustion, a gas supplyv pipe and fuel burners the latter being arranged in said ducts, two sets of rcg'enerators coinmunicating with the ducts on opposite sides of theI furnace respectively, provided with discharge ports opening directly to the atmosphere and arran ed above the combustion chamber, air pipes or introducing airA under pressure into the regenerators, and reversing valvesfor said gas pipe,

air pipes and regenerator discharge ports whereby the air maybe introduced .into the furnace through either set of regenerators and gas through the corresponding set lof burners and whereby the products of combustion may be .discharged therefrom through the other set of regenerators.

16. A` furnace comprising a relatively long, narrow combustion chamber, ducts on l opposite sides thereof in staggered relation for the introduction of. air and discharge of products of combustion, a gas `supply pipe and fuel burners the latter being arranged in said ducts, two sets of regenerators cominunicating with the ducts on opposite sides of the furnace respectively, provided with discharge ports opening directly to the at inosphere and arranged above the combustion chamber, air pipes for introducing air under pressure into the regenerators, reversing valves for said gas pipe, air pipes and regenerator discharge ,ports whereby the air may be introduced into the furnace through either set of regenerators and gas through the corresponding set lof burners and wherepipes for in- Std by the products of combustion may be. discharged'therefrom through the other set of regenerators,. and 'means for simultaneously operating said valves.

17. ln a furnace, the' combination of a combustion chamber, two sets of regenerators of substantially the same width as the combustion chamber arranged lengthwise thereof and above the same and provided with. discharge openings in the top, ducts leading from one set of regenerators into the combustion chamber on, one side and similar ducts leading-from the other set of regenerators into the combustion chamber on the other side, a gassupply pipe, branch pipes connected therewith and' extending valong opposite sides of the furnace and provided with burnersprojecting into said ducts,"a valve for directing the gas to the burners on either side-of the furnace, shut- Ating it od from the burners on the opposite side, .an air supply pipe for air under pressure" provided with branches extending along opposite sides of the furnace,one comv municating with one set of regenerators, the other with the other set, an air valve to direct the air into either set of regenerators and shut it od from the other set, and valves po close the discharge ports of the regenerors.

18. lin a furnace, the combination of a combustion chamber, two sets of regenerators of substantially the saine width as the combustion Achamber arranged lengthwise .thereof and above the same and provided with discharge openings in the top, ducts leading from one set of regenera'tors into the combustion chamber on one side and similar ducts leading from the other set of regenerators intothe combustion chamber on the i other side, a gas supply pipe, branch pipes connected therewith and extending along opposite sides of the furnace and provided with burners projecting into said ducts, a valve for directing the gas to the burners on either side of the furnace, shutting it od from the burnersvon the opposite side, an air supply pipe for air under pressure provided with branches extending along oppositesides of the furnace, one communicat in with one set of regenerators, the other with the other set, an air valve to direct the air into either set of regenerators and shut 1t' olf from the other set, valves to close the discharge ports of the regenerators, and

ARTHUR L. sravENs.

as to reverse them with ica

Images