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US1488660A - Arch construction for furnaces - Google Patents

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US1488660A
US1488660A US537719A US53771922A US1488660A US 1488660 A US1488660 A US 1488660A US 537719 A US537719 A US 537719A US 53771922 A US53771922 A US 53771922A US 1488660 A US1488660 A US 1488660A
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arch
bricks
brick
furnace
furnaces
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US537719A
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Frank B Bigelow
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MURPHY IRON WORKS
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MURPHY IRON WORKS
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23MCASINGS, LININGS, WALLS OR DOORS SPECIALLY ADAPTED FOR COMBUSTION CHAMBERS, e.g. FIREBRIDGES; DEVICES FOR DEFLECTING AIR, FLAMES OR COMBUSTION PRODUCTS IN COMBUSTION CHAMBERS; SAFETY ARRANGEMENTS SPECIALLY ADAPTED FOR COMBUSTION APPARATUS; DETAILS OF COMBUSTION CHAMBERS, NOT OTHERWISE PROVIDED FOR
    • F23M5/00Casings; Linings; Walls
    • F23M5/06Crowns or roofs for combustion chambers
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27FURNACES; KILNS; OVENS; RETORTS
    • F27DDETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D1/00Casings; Linings; Walls; Roofs
    • F27D1/02Crowns; Roofs
    • F27D1/021Suspended roofs
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27FURNACES; KILNS; OVENS; RETORTS
    • F27DDETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D1/00Casings; Linings; Walls; Roofs
    • F27D1/12Casings; Linings; Walls; Roofs incorporating cooling arrangements
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27FURNACES; KILNS; OVENS; RETORTS
    • F27DDETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D9/00Cooling of furnaces or of charges therein
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27FURNACES; KILNS; OVENS; RETORTS
    • F27DDETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D9/00Cooling of furnaces or of charges therein
    • F27D2009/0002Cooling of furnaces
    • F27D2009/0064Cooling of furnace arches

Definitions

  • My present invention concerns the means for supporting the brick arches of furnaces, especially those of the flat type, and similar structures, its chief object or prime purpose being the provision of a novel and improved arch or arch-brick carrying or sustaining means the employment of which will permit a more economical use of the bricks constituting the arch and a better relation of the bricks to one another, articularly the superposed bricks at the sides and back of the furnace.
  • Une aim of the invention is to supply means for supporting the bricks in suchv a manner that they may be individuall replaced when burned out or destroyed and in such a way that the new brick will not be unduly subjected to the heat of the furnace and hence not unnecessarily consumed or deteriorated by such heat.
  • the several bricks are supported individually or singly from above, and, as the bricks become gradually burned away or consumed by the heat, they become somewhat thinner and ultimately some of them require replacement.
  • the lower surface of the new brick used as a substitute for an old one, should register substantially with the corresponding faces of the remaining partly-wasted bricks, and, accordingly, the brick hangers are made adjustable as to length, whereby numerous bricks of different thicknesses may be supported in such a way that their under faces will be practically flush with no brick or bricks unduly or excessively exposed to the consuming or destroying heat.
  • the marginal bricks are positioned directly above other lower rows of bricksI supported on the correvshould be capable of substantially unrestrained sidewise or lateral movement due to the varying degrees of heat to which they are subjected.
  • Figure 1 is a fragmentary sectional view taken from the rear of the furnace looking forwardlyrinto the latter, some of the elements of the structure being omitted to more clearly depict the details of construction;
  • Figure 2 is a fragmentary, longitudinal, vertical section through the back part of the arch showing the supporting means for Y the bricks;
  • Figure 3 is vertical, fragmentary crosssection through a part of the arch near one ⁇ side of the latter.
  • Figure 4 is an enlarged vertical section on line lf-4: of Figure 2.
  • the furnace is of the usual Murphy type comprising a V-shaped grate 11, clinker grinder 12, opposed coking-plates 13, 13, associated sidewise-reciprocating Stoker-boxes 14, 14, superposed fuel-magazines 15, 15, airues 16, 16, longitudinal arch-pla ⁇ tes 17, 17, and rows of arch-plate bricks 18, 18, supported on the arch-plates and held or locked in position lby appropriate latches 19, the lifting or elevation vof which releases the bricks permitting their ready replacement.
  • Murphy type comprising a V-shaped grate 11, clinker grinder 12, opposed coking-plates 13, 13, associated sidewise-reciprocating Stoker-boxes 14, 14, superposed fuel-magazines 15, 15, airues 16, 16, longitudinal arch-pla ⁇ tes 17, 17, and rows of arch-plate bricks 18, 18, supported on the arch-plates and held or locked in position lby appropriate latches 19, the lifting or elevation vof which releases the bricks permitting their ready replacement.
  • the Hat suspended arch proper 20 is compos'ed of a plurality of bricks 21 arranged in horizontal, longitudinal and transverse rows, as is clearly depicted in Figure 1, and, when the arch is new, all ofthese bricks or refractory blocks will be of practically the same thickness and will unitedly present a substantially smooth lower face.
  • Each such arch-brick has an undercut or inverted T-shaped groove across its top face for the purpose of accommodating or receiving a suitably-shaped transversely apertured shoe 22 having an enlarged lower part occupying the undercut section of the brick cavity.
  • Each brick shoe of this kind is supported from a pipe 23 above by means of a chain 24 with hook ends 25 and 26, the former taking into the eye or hole of the shoe and the latter engaging the appropriate link of the chain to support the brick at the desired or required height, such velevation of the brick obviously being subject to adjustment by catching the hook in any desired link of the chain.
  • he construction comprises one vsuch upper, apertured or unperforated pipe, as the case may be, for each longitudinal row of bricks, these several pipes being suiiicient- 1y high above the bricks to permit the replacement of any one of the latter without disturbance of the others, the pipes being supported by front and rear cross I beams 27 of which only the ,latter is shown in the drawings.
  • each such pipe extends rearwardly through a hole in the web of the corresponding I beam projecting back thereof some distance.
  • each brick 31 must bear on the top plane face of the corresponding lower arch-plate brick with sufficient pressure to assure a com aratively or relatively tight joint between t em, but this pressure must not be suiiicient or reat enough to materially hamper or retar the bodily movement of the uppler brick over the lower one as is caused by t e expansion and contraction of the arch under the wide range of temperatures to which it is subjected.
  • each pipe 23 supports an apertured sealing-brick 33 mounted directly on the end of the pipe by the reception of the latter in its cavity, the brick or block being held in place on the pipe by a pipe-plug 34 maintained in position by a catch 35 inside of and having a downturned end engaging av hole in the pi e.
  • the end-bricks 37 of the arch are of the cross-sectional shape indicated in'Fi ure 2, and they are individually or separate y su ported on the several pipes by turn-buck e or other suitable hangers 38 in much the same manner that the bricks 31 are held in lace.
  • An arch of this general character usually requires repairing rather than the renewal of the entire arch, and if a local deterioration can be repaired easily and inexpensively, as is permitted by this improved construction, the life of the arch as a whole is lengthened many times.
  • the arch-plate bricks are independently supported or held in place and can be quickly and easily removed and replaced without interfering with any other portion of the arch.
  • the present improved construction provides for the elimination of expansion strains, and the cracking and spalling of bricks due to the expansion and pressure of adjoining bricks.
  • a furnace arch structure the combination of an arch-plate, a row of arch-plate bricks mounted thereon, a brick arch composed of a plurality of bricks, means adjustable as to length supporting said bricks independently from' above, whereby the under surface of the arch may be maintained substantially smooth even though the bricks are of-dilierent thicknesses, said arch having a border row of bricks each of which atleast in part is over the row of arch-plate bricks, and adjustable means supporting said border bricks independently from above to permit regulation of the contactual relation of the border bricks with the arch-plate bricks.
  • a brick arch means to support the arch, a row of sealing bricks at the rear of the arch, means to support said sealing bricks, a row of end bricks for the arch below said sealing bricks, and means adjustable as to len th supporting only said end bricks individually from above, whereby the contactual relation of said end and sealing bricks may be controlled to maintain the joints between them substantially tight but without material interference with the expansion and contraction of the arch.
  • a furnace arch structure the combination of a plurality of spaced supports disposed lengthwise the furnace, opposed archplates, rows of arch-plate bricks mounted on said arch-plates, an archcomposed of a plurality of bricks including rows of border bricks at least in part located over said arch-plate bricks, means adjustable as to length su porting the bricks of said arch individua ly from above from said spaced supports, whereby a practically smooth under surface of the arch may be maintained even though the bricks thereof are' of different thicknesses, and whereby the joints between the border and arch-plate bricks may be maintained practically tight without substantial interference with the expansion and contraction of the arch, a row of sealing bricks at the rear of the furnace mounted on said spaced supports, a row of end bricks for the arch below said sealing bricks, and means adjustable as to length supporting said end bricks individuall ,from above whereby the contactual relation of said end and sealing bricks may be controlled to maintain the joints between.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Vertical, Hearth, Or Arc Furnaces (AREA)
  • Furnace Housings, Linings, Walls, And Ceilings (AREA)

Description

p l y '1924s 1488,6S0
- F. B. BlGELoW ARCH CONSTRUCTION FOR FURNACES Filed Fb- 20. 1922 2 ShGQS-Shee l lavan/Zim @i gn) @y im April 1, 1924. 1,488,660
F. B. BIGELOW ARCH CONSTRUCTION FOR FURNACES Filed Feb- 20.- 1922 2 Sheets-Sheet 2 mmm" A A Patented Apr. 1, 1,924.
1,488,660 PATENT OFFICE.
FRANK B. BIGELOW, 0F DETROIT, MICHIGAN, ASSIGNOR T0 MURPHY IRON WORKS, 0F DETROIT, MICHIGAN, A CORPORATION 0F MICHIGAN.
ARCH CONSTRUCTION FOR FURNACES.
Application lined February 20, 1922.' Serial No. 537,719.
To all 'whom t may concern:
Be it known that I, FRANK B. BIGELow, a citizen of the United States, residin at Detroit, in the county of Wayne and tate of Michigan, have invented certain new and useful Improvements in Arch Constructions 4for Furnaces, of which the following is a specication. v
,My present invention concerns the means for supporting the brick arches of furnaces, especially those of the flat type, and similar structures, its chief object or prime purpose being the provision of a novel and improved arch or arch-brick carrying or sustaining means the employment of which will permit a more economical use of the bricks constituting the arch and a better relation of the bricks to one another, articularly the superposed bricks at the sides and back of the furnace.
,Une aim of the invention is to supply means for supporting the bricks in suchv a manner that they may be individuall replaced when burned out or destroyed and in such a way that the new brick will not be unduly subjected to the heat of the furnace and hence not unnecessarily consumed or deteriorated by such heat.
To this end, the several bricks are supported individually or singly from above, and, as the bricks become gradually burned away or consumed by the heat, they become somewhat thinner and ultimately some of them require replacement.
Under these circumstances, it is desirable that the lower surface of the new brick, used as a substitute for an old one, should register substantially with the corresponding faces of the remaining partly-wasted bricks, and, accordingly, the brick hangers are made adjustable as to length, whereby numerous bricks of different thicknesses may be supported in such a way that their under faces will be practically flush with no brick or bricks unduly or excessively exposed to the consuming or destroying heat.
Stated somewhat differently, after an arch has been in service for a length of time and subject to high furnace temperatures, it decreases in thickness, and in replacing a new brick in an old arch of the known form, the new brick will extend below the under surface of the arch and be exposed to the furnace temperature on five sides, and consequently 1t is subject to rapid deterioration, whereas, in the improved arch of this appplication, when inserting a new brick, the supporting means therefor can be shortened so as to place the under surface or face of the new brick flush with the balance ofthe arch, thus securing full life of the new brick and adding 'materially to the life of the arch.
Atthe sides of the arch, the marginal bricks are positioned directly above other lower rows of bricksI supported on the correvshould be capable of substantially unrestrained sidewise or lateral movement due to the varying degrees of heat to which they are subjected.
By means of such adjustable brick hangers or supports just the right relation between such bricks may be easily attained and maintained.
A similar situation is resent at the back of the arch and it is care for in like manner.
In order to enable those skilled in this art to fully understand the structural and functional advantages of a furnace embodying this invention, in the accompanying drawings forming a part of this specification, l have illustrated a, desirable and preferred embodiment of the invention and in. the several views thereof, like reference characters have been used to designate the same parts.
fn these drawings Figure 1 is a fragmentary sectional view taken from the rear of the furnace looking forwardlyrinto the latter, some of the elements of the structure being omitted to more clearly depict the details of construction;
Figure 2 is a fragmentary, longitudinal, vertical section through the back part of the arch showing the supporting means for Y the bricks;
Figure 3 is vertical, fragmentary crosssection through a part of the arch near one `side of the latter; and
Figure 4 is an enlarged vertical section on line lf-4: of Figure 2.
n 1,4ss,eoo
In the particular embodiment shown, although as will be obvious to those skilled in this art, the invention may be satisfactorily employed in furnaces of radically dill'erent styles, the furnace is of the usual Murphy type comprising a V-shaped grate 11, clinker grinder 12, opposed coking- plates 13, 13, associated sidewise-reciprocating Stoker-boxes 14, 14, superposed fuel- magazines 15, 15, airues 16, 16, longitudinal arch-pla` tes 17, 17, and rows of arch- plate bricks 18, 18, supported on the arch-plates and held or locked in position lby appropriate latches 19, the lifting or elevation vof which releases the bricks permitting their ready replacement.
The Hat suspended arch proper 20 is compos'ed of a plurality of bricks 21 arranged in horizontal, longitudinal and transverse rows, as is clearly depicted inFigure 1, and, when the arch is new, all ofthese bricks or refractory blocks will be of practically the same thickness and will unitedly present a substantially smooth lower face.
Each such arch-brick has an undercut or inverted T-shaped groove across its top face for the purpose of accommodating or receiving a suitably-shaped transversely apertured shoe 22 having an enlarged lower part occupying the undercut section of the brick cavity.
Each brick shoe of this kind, except those at the side and rear margins of the flat arch, is supported from a pipe 23 above by means of a chain 24 with hook ends 25 and 26, the former taking into the eye or hole of the shoe and the latter engaging the appropriate link of the chain to support the brick at the desired or required height, such velevation of the brick obviously being subject to adjustment by catching the hook in any desired link of the chain.
he construction comprises one vsuch upper, apertured or unperforated pipe, as the case may be, for each longitudinal row of bricks, these several pipes being suiiicient- 1y high above the bricks to permit the replacement of any one of the latter without disturbance of the others, the pipes being supported by front and rear cross I beams 27 of which only the ,latter is shown in the drawings.
At the front of the furnace such pipes are open to the outer air, but this detail has not been illustrated because it forms no part of the present invention, and as is fully indicated in Figure 2, each such pipe extends rearwardly through a hole in the web of the corresponding I beam projecting back thereof some distance.
' In the operation of the furnace, outer air, by the draft of the furnace, is drawn in through these several pipes and delivered through their holes or apertures near their rear ends in small jets into the space above the arch, thus keepingv the pipes cool and Each such brick has one of the usual shoes 22, but this is suspended from 'the pipe by a reversely-threaded turn-buckle hanger 32 which gives opportunit for nicety of adjustment as to length t us accurately governing or gauging the position of the brick which it supports.
The flat under surface of each brick 31 must bear on the top plane face of the corresponding lower arch-plate brick with sufficient pressure to assure a com aratively or relatively tight joint between t em, but this pressure must not be suiiicient or reat enough to materially hamper or retar the bodily movement of the uppler brick over the lower one as is caused by t e expansion and contraction of the arch under the wide range of temperatures to which it is subjected.
At the rear of the furnace, the projecting part of each pipe 23 supports an apertured sealing-brick 33 mounted directly on the end of the pipe by the reception of the latter in its cavity, the brick or block being held in place on the pipe by a pipe-plug 34 maintained in position by a catch 35 inside of and having a downturned end engaging av hole in the pi e.
The part o the brick recess accommodating the plug but not occupied by the latter is lilled by a fire-clay p ug 36, all as is fully illustrated in Figure 2 and as will be readily understood.
The end-bricks 37 of the arch are of the cross-sectional shape indicated in'Fi ure 2, and they are individually or separate y su ported on the several pipes by turn-buck e or other suitable hangers 38 in much the same manner that the bricks 31 are held in lace.
The accurate and delicate screw-t read adjustment permitted by such hangers allows the co-acting flat faces of the bricks 37 and 33 to be brought into and kept in proper Contact under all conditions of service, thus rendering certain and guaranteeing the correct tightness or seal of the joint without interference with the necessary relative movements of these parts by reason lof expansion and contraction of the elements of the structure subjected to the heat of the furnace.
In Figure 1 of the drawing all of the bricks of the main body of the arch are of the same thickness and their hangers are adjusted for uniform length. This condition could well represent the construction when it is first installed.
In Figures 2 and 3 the bricks or refractory blocks are of different thicknesses and their hangers or supporters have been adjusted accordingly to cause them to present a practically smooth under surface exposed to the direct heat of the furnace.
An arch of this general character usually requires repairing rather than the renewal of the entire arch, and if a local deterioration can be repaired easily and inexpensively, as is permitted by this improved construction, the life of the arch as a whole is lengthened many times.
In this new structure, the space at the rear of the arch is closed by special bricks or blocks, so attached or supportedy that they cannot be forced olf of the supporting members by the expansion of the arch and at the same time the construction keeps the joints tight thus avoiding an inefficient operation of the furnace or an injurious iow or passage of the heated gaseous products of combustion.
It should be noted in passing that the arch-plate bricks are independently supported or held in place and can be quickly and easily removed and replaced without interfering with any other portion of the arch.
Thus every brick in the arch is-independently supported and can be taken out and replaced without disturbing the balance of the arch.
The present improved construction, as will be understood without diiliculty, provides for the elimination of expansion strains, and the cracking and spalling of bricks due to the expansion and pressure of adjoining bricks.
The invention is not limited and restricted to the precise and exact details of structure shown and described since these may be modified within radical limits without departure from the heart and essence of the invention and without the sacrifice of any of its substantial benefits and advantages.
` I claim:
1. In a furnace arch structure, the combination of an arch-plate, an arch-platebrick mounted thereon, a brick arch having a border brick at least in part over said archplate brick, and means supporting said border brick from above and capable of permitting variation in the contactual relation of such arch-plate and border bricks.
2. In a furnace arch structure, the combination of an arch-plate, a row of archlate bricks mounted thereon, a brick arch aving a border row of bricks each of which at least in part is over the row of arch-plate bricks, and adjustable means supporting said border bricks independently from above to permit'regulation of the contactual relation of the border bricks with the arch-plate bricks.
3. In a furnace arch structure, the combination of an arch-plate, a row of arch-plate bricks mounted thereon, a brick arch composed of a plurality of bricks, means adjustable as to length supporting said bricks independently from' above, whereby the under surface of the arch may be maintained substantially smooth even though the bricks are of-dilierent thicknesses, said arch having a border row of bricks each of which atleast in part is over the row of arch-plate bricks, and adjustable means supporting said border bricks independently from above to permit regulation of the contactual relation of the border bricks with the arch-plate bricks. l
l 4. In a furnace arch structure, the combination of a brick arch, means to support the arch, a row of sealing bricks at the rear of the arch, means to support said sealing bricks, a row of end bricks for the arch below said sealing bricks, and means adjustable as to len th supporting only said end bricks individually from above, whereby the contactual relation of said end and sealing bricks may be controlled to maintain the joints between them substantially tight but without material interference with the expansion and contraction of the arch.
5. In a furnace arch structure, the combination of a plurality of spaced supports disposed lengthwise the furnace, opposed archplates, rows of arch-plate bricks mounted on said arch-plates, an archcomposed of a plurality of bricks including rows of border bricks at least in part located over said arch-plate bricks, means adjustable as to length su porting the bricks of said arch individua ly from above from said spaced supports, whereby a practically smooth under surface of the arch may be maintained even though the bricks thereof are' of different thicknesses, and whereby the joints between the border and arch-plate bricks may be maintained practically tight without substantial interference with the expansion and contraction of the arch, a row of sealing bricks at the rear of the furnace mounted on said spaced supports, a row of end bricks for the arch below said sealing bricks, and means adjustable as to length supporting said end bricks individuall ,from above whereby the contactual relation of said end and sealing bricks may be controlled to maintain the joints between.
them substantially tight but without material interference with the expanslon and contraction of the arch.
i FRANK B. BVIGELOW,
US537719A 1922-02-20 1922-02-20 Arch construction for furnaces Expired - Lifetime US1488660A (en)

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