US2409442A

US2409442A - Method and apparatus for cleaning furnace checkers and flues

Info

Publication number: US2409442A
Application number: US611602A
Authority: US
Inventors: William J Montgomery
Original assignee: Individual
Current assignee: Individual
Priority date: 1945-08-20
Filing date: 1945-08-20
Publication date: 1946-10-15
Anticipated expiration: 1963-10-15

Description

Oct. 15, 194

w. J. MQNTGOMERY METHOD AND APPARATUS FOR CLEANING FURNACE CHECKERS AND FLUES Filed Aug 20, 1945 8 Sheets-Sheet 1 Attorney:

1946. w. J. MONTGOMERY- 2,409,442

METHOD AND APPARATUS FOR CLEANiNG FURNACE CHECKERS AND IiLUES Filed m. 20, 1945 s Sheets-Sheet 2 Inventor LLIAMJMoIvTGoMER M ma;

t- 1946. v ,w. J. MONTGOMERY 2,409,442

METHOD AND Armnuus FOR CLEANING FURNACE CHECKERS AND FLUES Filed Aug. 20, 1945 I 8 Shuts-Sheet 3 AND FLUES Oct. 15, 1946; r w. J. MONTGOMERY METHON AND APPARATUS FOR CLEANING FURNACE GHECKERS Filed Aug. 20, 1945 8 Sheets-Sheet 4 Inventor 7 CZMONT' 6 o M E i);

I W. J. MONTGOMERY METHOD, AND APPARATUS FOR GLEANINGFURNACE CHECKERS AND FLUES Oct.15

Filed Aug 20, 1945 8 Sheets-Sheat 5 I nventar MLLjAMcI/VoN'reoMER w" 15, METHOD AND APPARATUS FOR CLEANING FURNACE CHECKERS ANDFLUES w. J. MONTGOMERY Inventor MER y,

w. J. MONTGOMERY 2,409,442 METHOD AND APPARATUS FOR CLEANING FURNACE CHECKERS AND FLUES Get. 15,1946.

Filed Aug. 20, 1945 8 Sheets-Sheet 7 iii Ml I ll 1 I Inventor Mum/w CZM TQoMER Wfl/////////% Oct. 15, 1946. w. J, MONTGOMERY I 2,4095442 METHOD AND APPARATUS FOR CLEANING FURNACE CHECKERS AND FLUES Filed Aug.- 20, 1945 s Sheets-Sheet a' v b zventor CZMNTGOMERK M21: Ila/w Patented Oct. 15, 1946 4 METHOD AND APPARATUS FOR CLEANING FURNACE CHECKERS AND FLUES William J Montgomery, Warren, Ohio Application August 20, 1945, Serial No. 611,602

17 Claims.

This invention relates to improvements in a method and apparatus for cleaning furnace checkers and flues, and has for its primary object the removal of flue dust and debris from the checkers and flues.

Another object is to carry the flue dust and debris to the base of the furnace stack pit or uptake and deposit it on the floor of the furnace stack pit or uptake.

Another object is to remove the flue dust and debris from the floor of the furnace stack pit or uptake either automatically or by hand without interrupting the operation of the furnace.

The above and other objects may be attained by employing this invention which embodies among its features directing a fluid blast against and through the furnace checkers to remove flue dust and debris, suspending the flue dust and debris so removed on a moving fluid blast directed toward the base of the stack pit or uptake of the furnace, depositing the flue dust and debris on the floor of the stack pit or uptake of furnace, isolating the flue dust and debris so deposited from the rest of the stack pit or uptake so that it may be removed without interrupting the operation of the furnace.

Other features embody conduits mounted atop the checkers or at any elevation of the checkers having nozzles for directing a, blast of fluid against or through the checkers, conduits extending longitudinally of the side walls of the furnace flues and having nozzles directed in such a manner as to suspend the flue dust and debris loosened from the checkers on a fluid blast which moves toward the base of the stack pit or uptake of the furnace, and doors adapted to be moved into a position to isolate the flue dust and debris which is deposited on the floor of the stack pit or uptake by the moving blast so that removal of the flue dust and debris from the floor of the stack pit or uptake may progress without interrupting the operation of the furnace.

Other features include removing the flue dust and debris from the floor of the stack pit or uptake by vacuum, and water-cooling the isolating doors, not only to protect them from the intense heat at the base of the stack pit or uptake, but also to reduce the temperature in the isolated area of the furnace stack pit or uptake to protect workmen who may enter the isolated area for the removal of the debris by hand.

In the drawings:

Figure 1 is a horizontal sectional view through a regenerative furnace showing the checker chambers and flues leading to the stack,

Figure 2 is a longitudinal sectional view taken substantially on the line 2-2 of Figure 1,

Figure 3 is a horizontal sectional view taken substantially on the line 3-3 of Figure 2, a

Figure 4 is a vertical sectional view taken substantially. on the line 44 of Figure 2, y

Figure 5 is an enlarged sectional view taken substantially on the line 5-5 of Figure 1,

Figure 6 is a vertical sectional view taken substantially on the line 6-6 of Figure 5,

Figure 7 is a fragmentary enlarged horizontal sectional view through the base of a stack and a portion of the flues leading thereto showing a modified form of isolating door arrangement,

Figure 8 is a transverse sectional view taken substantially on the line 8-8 of Figure 7,

Figure 9 is a sectional view taken substantially on the line 9-9 of Figure 7,

Figure 10 is an enlarged transverse sectional View through one of the blast conduits and its nozzle,

Figure 11 is a transverse sectional view taken substantially on the line ll-|l of Figure 5.

Figure 12 is an enlarged detail sectional view taken substantially on the line |2l 2 ofFigure 3,

Figure 13 is a fragmentary longitudinal sectional view taken substantially on the line [3-13 of Figure 12, and

Figure 14 is an enlarged detail fragmentary sectional view through the base of a furnace stack or uptake showing a modified form of isolating door and debris-receiving pit.

Referring to the drawings in detail, a furnace designated generally 20 of the regenerative type is provided with the usual hearth 2| (Fig. 2) in which the combustion of the mixed gases leaving a mixing chamber 22 takes place. Leading to the mixing chamber are the usual air and

gas conduits

23 and 24, respectively, which in turn communicate at their lower ends with the usual checker chambers 25 and 26 containing walls 21 of checker brick. The check chambers 25 and 26 communicate at their ends opposite the air and

gas conduits

23 and 24 with flues 28 which lead to a stack 29. The furnace is provided with the usual reversing valves 30 (Fig. 1) and the arrangement of the various passages for the air and gas supply is of conventional form, following that ordinarily employed in regenerative furnaces of the type to which this invention relates.

vMounted atop the checker walls 21 in respective checker chambers 25 and 2-8 are blast pipes or conduits 31 provided at spaced intervals with downwardly directed nozzles 32 which are so arranged that a blast of fluid is directed against the side faces of the checker walls 25 and 26 to loosen flue dust and debris and cause it to be blown downwardly into the lines 28. These blast pipes 3| are protected from the intense heat generated within the checker chambers, first, by a layer of asbestos 33 of not too dense a form so as to allow for expansion and contraction of the pipes 3| under the influence of temperature. Surrounding the exterior of the asbestos covering 33 of the pipes 3| is a loosely packed insulating substance preferably of a finely divided nature, such as Sil-o-cell 34, which in turn is held in place by an outer ceramic cylindrical shell 35 formed of a suitable material, such assilica brick, and the entireinsulated piping unitis supported atop the checker walls by a suitable ceramic structure 36 which may take the form of rectangular slabs, as illustrated in Figures 4 and 12.

The pipes 3| lead outwardly through'the end walls of the checker chambers and Hand are connected to a header 3'! which'in turn is connected through a valve 38 to a pressure supply line 39 which may be connected to a source'of pressure supply, such as an air pressurereservoir or in other instances itmay be found desirable to connect the pipe 39 toa source of high pressure steam. As illustrated inFigure 3, the pressure line 39 is connected througha two-way valve 43, which leads through branch pipes to the valve 38, sothat one or the other set of checker chambers onopposite sides of the furnace mayselectively be cleaned. As illustrated in'Figure 3,the pressuresupply line39 is provided with a lead which extends into each checker'chamber on opposite sides of thefurnace and is providedwith a return bendd I so that the fluid passing through the pipes willbe superheated before it enters the header 3'! and blast pip'es "3i. A suitable shut-off valve 42 is arranged to controltheflow of fluid through the supply pipes"39 and insome instances I find it desirable to introduce a pressure-reducingvalve 43, and suitable strainers 44 according to the requirements of the; particular installation.

Builtlongitudinally along each 'flue"28 atthe junctionof itsflooriand its vertical side walls of suitable heat resisting "material, such "as silica brick, is a guardor housing 45provide'd with a vertical curb 46, which curbs cooperate to form 'a longitudinally extending wellortrough ll in each suchflue. Ea0h'housing15isformed with a longitudinally extending chamber 48 containing a suitable insulating material 49 which surrounds a blast pipe or conduit-5U. This blast pipe or conduit is provided at spaced intervalswith blast nozzles 5| which are directed outwardly and at any desired angle,through the curb 46 and issurroundedby a suitable thermal insulation 52. The nozzles 50 are preferably placed at such an angleas tocause thefluid blast issuing therefrom S to bedirected in'the 'generaldirection'of the stack "2950- that a'longitudinalfiow of the fluid issuing from the jet't'il will be-toward the'stack. "These pipes 53 are connected through the medium of risers 53 to'the pressure supply'line39, and so arrangedas to be separately controllable through valves 54 arranged at suitable points in'thensystern.

Formed-at the junction of the floor 55 and th side Walls andback wall 56 and5l, respectively, of the base of the stack29 is a'curb'58 forming a well 59'intowhich the flue dust and'debris is deposited. Blast pipes 60 are'embedded in the curb 58 and are provided with'nozzles El'leading outwardly throughthe sidewall of the curb toward the interior of the well 59. These blast pipes 50 are connected in any suitable manner to the pipe 39 leading from thesource of'fiuid pressureand suitable valves (not shown) are. interposed for the'purpose of regulatingthe flow of fluidinto the pipes 60. Formed inthe'fioor of the stack approximately mid-way "between the sides and ends of'the well or pit 59 is an opening B3-through which a dischargepipe 64 extends. This discharge pipe is connected'througl'i a'riser "65 with an exhaust fan 56,'which in turn is connected to a pipe 6'! with a suitable receptacle for :back wall 51 of the base of the stack to the lower end of the arch 68, which establishes connec- 'tion=between the flue 28 and the stack 29, and

against opposite side Walls 56 of the base of the stack, are inclined channels 69. Welded or otherwise secured to the inner faces of the webs of the channels 69 are angles 10 which extend upwardly beyond the ends of the channels, as illustrated in Figure 5, and are supported at their extreme upper ends on suitable pedestals H. These'channels EQand angles 10 form guides'for supporting a door frame 12 carrying a layer of insulating 'brick 13 which 'forms the door for isolating the floor '55 and well or pit 59 of the stack 29 from the stack when the flue dust'and debris'is to be removed from the base thereof. In instances where it is 'desired'to provide cooling for the door T3 and'the isolated-portion of the stack 29, the insulating brick is provided with longitudinal passages for the reception of cooling fluid-receiving pipes 74 which are connected together in such fashion asto' permit the flow of cooling fluid therethrough. Carried adjacent the door 13 bythe'channels 69 are suitable conduits '15 which are preferably embedded in a suitable supporting material 16, and these pipes 15 are likewise connected with the'source of cooling fluid so that additional cooling may be provided for the isolated portion of the stack and the channels 69 further protected against the intense heat from the furnace. Carried at'the upper end of the door frame 72 is an ear" to which a suitable elevating cable 18 is attached. This cable is carried over a sheave 19 supported in any suitable manner on a bracket and the cable 18 is connected to any suitable type of winding drum (not shown) by means of which the door frame 12 and the .insulatingbrick carried thereby may be lifted during thenormal operation of the furnace.

In the modified form of .stack'floor-isolating mechanism illustrated in Figures Ho 9, inclusive, I provide adjacent'the stock'base a pit 8| and extending horizontally across the arch 88 at its lower end is a channel '82. This channel extends into the pit 8|, as. illustrated in Figure "I, and has mounted therein at spaced intervals angles 83 for a purpose to be more fully hereinafter described. A similarchannel 84. extends horizontallyacross the back wall 51 of thebase of the stack and into the pit 8| substantiallyon a level with the'upper end of the arch 68. Like the channel 82, the channel 84 is provided with an angle85 for a purpose to be more fully'hereinafter described. Extending'between the

channels

82 and 84 are isolating doors 86 carrying at opposite ends rollers 81 which ride on the'fianges of the channels and the angles tofacilitate easy movement of the doors into open or closed position. Like the door 13,'the doors 86'may alsowbe provided with suitable cooling fluid. conduits 88 for the circulation of cooling fluid therethrough.

Alternatively to the form of doors illustrated in. FiguresS to 9, inclusive, there are instances when I find it desirable to employ at the base of the stack 29' a structure such as that illustrated in Figure 14. In such a case I provide at the base of the stacka pit 89 on the upper ends of the'side walls of which I support a door 90 on suitable rollers-9| which enable the door-'90 to be withdrawn from its position beneath the stack so that fluedustand debriswill be deposited in the-pit 89. In-order to facilitate the easy'removal of such material from the pit,'I provide a carriage 92 in the form-of a receptacle which may be readily moved from its position beneath the lower end of the stack by movement on rollers 83 in a horizontal direction. It will be understood, of course, that a suitable pit is arranged adjacent the pit 89 for; the reception of the carriage-92. V i

In operation, it will be understood that when a certain checker chamber or flue is 'tobe cleaned,

the proper valves are opened to direct the fluid blast from the pipes 39 through the superheaters 4! to the header 3'! and thence into the pipes 3| resting atop the checkers. The fluid issuing throughthe nozzles 32will be' directed against the sides of the checker: and down through checker openings so asto loosen any flue dust and debris and direct it downwardly into the flue 28 with which the checker chamber is connected. Simultaneously with the dislodgment of the flue dust and debris from the checkers under the influence of the fluid blast issuing from the nozzles 32 pressure is admitted through the risers 53 in the proper flue 28 so as to create a fluid blast in the wellor wells 41 of the flue passage which is being cleaned. Due to the angular disposition of the nozzles 5| leading from the blast pipe 50 at the bottom of the flue 28 a fluid blast will :be created which moves the flue dust and debris toward the stack 29. Rising at the stack 28 and at the end of the creation of the fluid blast, upon which the flue dust and debris have been sustained, the fluedust and debris will deposit on the floor of the stack until a sufficient quantity has been, accumulated to warrant its removal.

The isolating door 12 or 86, as the case may be, is then closed so as to isolatethe area upon which the flue dust and debris havelbeen deposited from the rest of the stack, afterwhich the removal of the fluedust and debris from the floor 55 of the stack may proceed,'either by hand or. automatically, by operating the exhaust fan 66 and discharging the flue dust anddebris through the ,pipes 64 and 61 to anysuitable receptacle. It

is to be noted that the isolation ,of the floorof the stack does not interrupt the flow of heated gases through the stack, though some constriction of the passage result. Such constriction is not serious, however, and enables the furnace to .be operated continuously without interrupting production for cleaning purposes.

The flue. cleaning process may be carried on continuously with the operation of the furnace by employing the pressure-reducing valve 43, which, while causing the fluid blast to serve somewhat as a booster to the stack draft, at the same time so regulates the pressure of the blast as to avoid interference with the furnace operation. Under such conditions of continuous operation, itis only. necessary periodically to manipulate the doors 12 or 86 so as to isolate the floor of the stack from the rest of the stack during the time that the stack cleaning is in progress. The operation of the structure illustrated in Figure 14 --is essentially the same as that previously described, except that the door 90 operates in a horizontal rather than an inclined plane, and the carriage 92 forms a receptacle for the reception of the flue dust and debris, which receptacle may periodically be withdrawn from its position beneath the stack when the door 98 is closed so that it may 'be emptied -at leisure. Doors or dampers (not shown) may be introduced in the '1. The herein described method of cleaning furnace checkers and flues which includes directing a fluid blast against the checkers to dislodge fine dust and debris therefrom, collecting the flue dust and debris so dislodged on the floor of the furnace stock, isolating the portion of the floor 0f the stack upon which the flue dust and debris is collected, and removing the flue dust and debris from the isolated area.

2. The herein described method of cleaning furnace checkers and flues which includes directing afluid blast against the checkers to dislodge flue dust and debris therefrom, conveying the flue dust and debris so dislodged to the base of the furnace stack, collecting the flue dust and debris on the floor of the furnace stack, isolating the portion of the floor of the stack upon which the flue dust and debris is collected, and removing the flue dust and debris from the isolated area.

'3. The herein described method of cleaning furnace checkers and flues which includes directing a fluid blast against the checkers to dislodge flue dust and debris therefrom, creating a fluid blast in the furnace flues which moves toward the stackof the furnace, conveying the flue dust and debris by said fluid blast to the base of the stack, collecting the flue dust and debris on the floor of the stack, isolating that portion of the floor of the stack upon which the flue dust and debris is collected, and'removing the flue dust and debris from the isolated area.

4. The herein described method of cleaning furnace checkers and flues which includes directing a fluid blast against the checkers to dislodge F flue dust and debris therefrom, collecting the flue dust and debris so dislodged on the floor of the furnace stack, isolating the portion of the floor of the stack upon which the flue dust and debris is collected, and extracting the flue dust and debris from the isolated area under the influence of vacuum.

5. The herein described method of cleaning furnace checkers and flues which includes directing a fluid blast against the checkers to dislodge flue dust and debristherefrom, conveying the flue dust and debris so dislodged to the base of the furnace stack, collecting the flue dust and debris onthe floor of the furnace stack, isolating the portion of the floor of the stack upon which the flue dust and debris is collected, and extracting the flue dust and debris from the isolated area under the influence of vacuum.

6. The herein described method of cleaning furnace checkers and flues which includes directing a fluid blast against the checkers to dislodge flue dust and debris therefrom, creating a fluid blast in the furnace flues which moves toward the stack ofthe furnace, conveying the flue dust and debris by said fluid blast to the base of the stack, collecting the flue dust and debris on the floor of the stack, isolating that portion of the "floor of the stack upon which the flue dust and debris is collected, and extractingthe flue dust and debris from the isolated area under the infiuence of vacuum.

without arresting the flow of heated gasesrfrom the unisolated' flues and checkers. of? the :furnace,

isolating that 3 portion :of ltheffloorcof :therstack eupon'which 'therflue; dust and :debris is;;collected, and removing theflue-:dust.:and debris? fromz .the

isolated area of thecstack.

18. The herein described method -;-of :cleariing furnace checkers andl fluesnwhich 1 includes aperiodically isolating certaini'ofthezchecker chambers and flues of afurnacexfromcother checkericha-m- :bersandflues of ,the furnace, gdirectingia fluid 'blastxagainst, the isolatedjcheckers vandalong-the isolated =flues toward ithe :stack :of the-furnace, :conveying v:by the fluid'xblasti' the 1 flue ,dust and .debrisdislodged :thereby along .;the flues .toward the base of the; stack. of athe furnace, collecting the flue,dust anddebrisontthe' floorgrof the;stack, without arresting the -1 flow ofheated gases 1 from thepunisolated fines. and checkers ofzthe-furnace, isolating .that; portion of the flooraof ,the stack ,uponwhich the .flue dustz'and debrisis collected "and extracting theflue dust :andtdebris; fronr-the isolatediareatunder the influence of-vacuum.

.- 9. The .herein described :method "of :cleaning t'furnacecheckers and flues whichincludes directing. a fluid; blastzagainstzthe checkersxtoa-dislodge .flue dust-zand debris therefrom, collectingpthe :flue dustand fclebris; so :dislodgedrom the -.floor ;.of

the furnace. stack, isolating the portion 10f the .floor of. the ;stacln.upon which:the rflue; dust:and ,debris is collected, -;decreasing the itcmperature within the isolated portion ofithecstach'gand re- ;moving. the flue; dust and-debris Homing-isolated area.

' 10. The herein idescribed rmethodz of: cleaning furnace-checkers andlfluesiwhicn includes; peri- :.o;dically isolating:certairroithe-:checker chambers and flues of abfurnacelfrom:o.ther checkerpchamrbers and ,flues of i the furnace, adirecting a ffiuid blast :againstithe,isolatedicheckers: andzzalong the isolated: fluesi-toward ttheestack :of@ the .;furnace,

collecting the flue dust and debris dislodgedvand carriedby. the fluid blast .on the floorof thegstack, without: arresting 1 the diow 10f: heatedigases from the. iunisolated flues and checkers of i the furnace --isolating-that portion ;of 2131.18 floor z of the stack upon. which, the ,fluedust;=and:-debris .istcollected, vdecreasing the temperature -:within the isolated portion of the stack,- -'and removing theziflue 'rdust and debris from the isolated area.

, 11. In aisystemifor-cleaning' f urnace checkers land fluesuthe combi-nationnw-ith a furnace-Which includes checker chambers, checker-s -,"in rsaid checker chambers, a stack and fluesestablishing communication between the checker chambers and the .stack,-of m eans to, create vanblast "of fluid tagainstthehcheckersand alongthe fines to dislodge fluedust. and debris from-the checkersand to ,acenvey it along the .flues to 1 the floors of the .-stack, -and meanstodsolate the portion of the ,stack in which the fine .dust and, debris, collects whereby removal c, the flue dustand, debrisfrom tthe isolated area of .the stack may progress without interference from the/heated, gases passing through the stack.

:12.;.In asystem" for cleaning furnace checkers an'di fluesi. the combination with a furnace which :includes pchecker chambers, checkers in said :checker chambers, astackaand flues establishing zcommunicationrbetween the checker chambers an'dgthe stack, of, means selectively to isolate cer- Itain checker chambers and 1flues :from other ..chambers andxflues of the furnace, means-for creating an air blast against the checkers in the isolated checker chambers to-.dislodge fluedust and:d'ebris: therefrom,- means for creating an 1 air :current throughthe isolated flues upon which the flue'hdust and :debris is conveyed toward. the base of sthezstack :andby which it is collected and deposited on the floorof the stack, and means to isolate only that part of the stack containing vthe flue dust and debris from the'remainderof .the stack-whereby thefluedust and debrismay be removed without interfering with the: flow of heated gases into the-stack.

.l3..In a system for cleaning furnace checkers and. flues, thecombination with a furnacewhich .includess checker chambers, checkers in said checker chambers, a stack and'flues establishing communication between the checker chambers and the stack, of meansto create a blast, of fluid against the checkers and along the fluesto dislodge flue dust and debris from the. checkersand to convey it along the flues to the floor of the stack, means to isolatethat portion of the stack inwhichthe flue dust and debris collects,,and means to decrease the temperature in the isolated portion of the stack.

14. In a systemfor cleaning furnace checkers and flues, the combination with a'furnace which includes checker chambers, checkers in said checker chambers, a stackan'd flues establishing communication between the checker chambers and thestack, of meansselectively to isolate certain checker chambers and'flues of the furnace, meansfor creating an air blast against the checkers in the isolated checker chambers to dislodge iflueidust'and debris therefrom, means for creatingantair 'current through the isolatedflues :upon which thei'flue'dust anddebris is'conveyed toward the base'of the stack and by which it is collectedanddeposited' on the floor of the stack,

means to isolate only that part of the stack containing the "flue 'dust and; debris from the "re- "mainder of' the stack, and means to cool the isoiatedportion of the stack.

"15;'The combination with means for'dislodging and conveying flue dust-anddebrisfrom-furnace checkers and depositing said flue 'dust and 'debris on'the floor -of-the stack of the furnace, 'of' a door adapted to-partially-close the stack to isolate the-floor fromthe'remainder of the stack Whereby removal of the flue dust and debris can progress-without interfering with the'operation 'of the furnace.

16.In combination with a furnace stack, a door -adapted to be moved into a position to'isolate the l floorhof thexstack from the :balance of .the

stack,:.and: means to support the door in 1 open' or -c10sed position.

1'7..='A :doorffor: isolatingzone'part not a furnace stacki fromzanother part .ofxsaid stack which includesgazpain of :spaced :guidesso .positioned; near ,theibasetofithe stack that whemthe dooris closed it 1ies-at such: .anangle t0-:the;;major;:axis of,:the stacktasxto allow theireepassage :of flue ,ggases through the stack, andwmeans to' open ;,or;c1ose .saidtdoor.

' WILLIAM-J.-MONTGOMERY.'