US2832401A

US2832401A - Open hearth burner

Info

Publication number: US2832401A
Application number: US219471A
Authority: US
Inventors: Ernest E Lail
Original assignee: Individual
Current assignee: Individual
Priority date: 1951-04-05
Filing date: 1951-04-05
Publication date: 1958-04-29
Anticipated expiration: 1975-04-29

Description

April 29, 1958 E. E. LML 2,832,401

OPEN HEARTH BURNER Filed April 5, 1951 Z5 Z4 i Snventor Ernest 15. La/'/ attom'egs United States atent 0 OPEN HEARTH BURNER Ernest E. Laid, Athol Springs, N. Y.

Application April 5, 1951, Serial No. 219,471

11 Claims. (Ci. 158--4.5)

This invention relates generally to the furnace burner art, and more specifically to a new and useful burner arrangement particularly adapted for use, for example, in open hearth furnaces.

it is a well known practice in open hearth steel making to provide fuel burners at opposite ends of the furnace, the burner control arrangement being such that when the burners at one end are firing, the burners at the other end are shut down. The exhaust from the active burners is caused to pass out of the furnace around the inactive burners and in to a checker assembly, where the heat of the exhaust gases is stored to warm the air drawn through the checker assembly for supporting fuel combustion in the furnace.

Certain serious problems exist in this type of furnace operation. For example, it is frequently necessary to adjust the burner direction. The necessity for such adjustments arises from different heating requirements during the various stages of each heat. Also, because of changes in the cont-our of the interior surfaces of the furnace, and variations in dimensions as a result of furnace rebuilding cr relining and the like, such burner adjustments are frequently required. Obviously, the conventional stationary burner installation, wherein the burner is mounted in a fixed position in the furnace wall, does not provide for such adjustments and is extremely unsatisfactory. Equally unsatisfactory is one solution which has been proposed, wherein the burner and its water jacket are adjustably supported within anenlarged opening in the furnace wall. This latter arrangement is unsatisfactory because ambient air leaks into the furnace through the opening around the burner, thus reducing the efficiency of the furnace. In addition, prior art apparatuses for moving such burners have usually proven to be relatively complex, cumbersome, and otherwise impractical.

Another problem which has been encountered is that preventing the entrance of exhaust gases and substances entrained therein into the inactive burner, which substances tend to clog the burner and its associated fuel lines. One solution to this problem which has been proposed is to continuously pass steam or a similar fluid through the in active burner at a substantially high pressure. While this prevent the entrance of exhaust gases into the inactive burner, it also interferes with the passage of exhaust gases around said burner and into the checker work, causing said gases to whirl and eddy and damage, often extensively, the roof lining of the furnace at that point.

An additional problem arises in protecting the inactive burner against injury from theintense heat of the furnace. While it has been proposed to temporarily bodily Withdraw the inactive burner from the furnace to protect it from such heat, the methods and structural arrangements which have been proposed for doing so are relatively complex, bulky and expensive.

Accordingly, it is an object of this invention to provide a furnace burner incorporatingmeans whereby the burner discharge direction can be easily varied as desired without changing the positional mounting of the burner.

Patented Apr. 29, 1958 It is also an object of this invention to provide a furnace burner having improved means automatically retracting the burner nozzle into an associated cooling jacket when said burner is shut down.

Another object of this invention is to provide an improved furnace burner arrangement incorporating valve means sealing the fuel line through the burner when it is shut down.

A further object of this invention is to provide an improved burner with a nozzle arranged to avoid contamination from the furnace exhaust and for self-cleaning operation.

In addition, it is an object of this invention to provide a burner having the aforementioned characteristics and which is relatively inexpensive to manufacture, simple and compact in construction, and completely reliable in operation.

The foregoing and other objects will become apparent upon reading the ensuing specification, together with the accompanying drawing wherein:

Fig. l is a cross sectional view of an open hearth furnace showing the novel burner of theinstant invention installed therein; and r Fig. 2 is a fore-shortened sectional view of the novel burner of the instant invention, with parts broken away for ease of illustration.

While the burner of the instant invention is herein described and illustrated as it is used in an open hearth furtrace, its adaptability clearly is not limited thereto and it can be used in other types of furnaces and installations.

There is shown in Fig. l a conventional open hearth furnace 1 comprising a hearth 2 on which the material to be treated is placed, and charging doors 3 through which said material is introduced into furnace 1. Flues .4 and 5 are located at opposite ends of the furnace, and lead into

checkers

6 and 7. Also located at said opposite ends of furnace 1 are

burners

8 and 9, said burners being mounted in the furnace wall and surrounded by heat resisting jackets 10 and 11 which are provided to protect

burners

8 and 9 from the heat of furnace 1.

Burners

8 and 9 are so arranged, as will become apparent, that when burner S is firing, burner 9 is shut down and it nozzle retracted, flue 4 acts as an uptake for secondary air, and flue 5 acts as a downtake for the furnace exhaust. Conversely, when burner 9 is firing, burner 8 is shut down and its nozzle retracted, flue 5 becomes an uptake, and flue 4 forms a downtake. While only two burners are shown in the drawings, it is to be understood that banks of burners can be used if desired.

Fig. 2 illustrates in detail one of the burners of the instant invention, in this case burner 9, it being understood that

burners

8 and 9 are identical in construction. Burner 9 comprises an annular cooling jacket 12 having a bushing portion 13 around its inner circumference and adjacent its forward end. A nozzle mount member 14 slidably and rotatably fits within bushing portion 13, and is externally shaped to a modified hour glass form as illustrated at 15. Although shown as a solid member, mount 14 could, if desired, be made in the form of a spider element. A fuel line 16 extends through mount 14 and toward the rear of burner 9, with the nozzle portion 17 of fuel line 16 (which is within the nozzle mount) being canted or in clined relative to the longitudinal axis thereof. An extension 18 of fuel line 16 is joined thereto by means of

flange members

19 and 20 secured to fuel line 16 and extension 18, respectively, as by welding, and locked together by means of bolts or rivets 21.

Flange members

19 and 20 are of a diameter substantially equal to the inner diameter of cooling jacket 12, whereby said flange members also act as a centering device for fuel line 16. Thus, the burner fuel line is split, for convenience in assembly and disassembly as well as in manufacturing.

The rearward end of cooling jacket 12 is sealed by a removable cover 22, and extension 18 of fuel line 16 extends through cover 22, being journaled therein at 23. A packing gland 24 is provided on cover 22 to seal the junction between said cover and said fuel line extension.

A turning wheel 25 is welded or otherwise mounted on fuel line extension 18 at a point exteriorly of cooling jacket 12, and is provided with spaced recesses 26 along its outer periphery. Therefore, the arrangement is such that by inserting a crowbar or similar tool in one or more of recesses 26 and manually exerting pressure thereon, fuel line 16 and its canted nozzle portion 17 can be turned in either a clockwise or counterclockwise direction whereby to vary the inclination of the nozzle 17 relative to the horizontal and vertical axes of burner 9. In this way, the direction of firing of burner 9 can be varied through a wide range without moving or repositioning the burner itself, so that the burner can be mounted in the furnace wall in a stationary and sealed installation. The burners are mounted in the furnace walls with just the rear portion of the cooling jacket extending outwardly from the furnace.

The instant invention also provides means for retracting the nozzle of the burner when inactive, and for closing the entrance to the fuel line thereof whereby to prevent furnace dirt from plugging said fuel line, as follows.

A frame or spider 27 is welded or otherwise secured to the rearward end of jacket 12, and extends rearwardly therefrom, having a transverse portion 28 at its rearward end. A cylinder 29, including a forward wall 30 and a rear wall 31, is mounted on member 28 and extends forwardly therefrom. Fuel line extension 18 extends through wall 3tl, being journaled therein, and extends into cylinder 29. Wall 30 contains a packing gland 32 which surrounds extension 18 and seals cylinder 29 against the admission of ambient atmosphere.

At its rearward end, fuel line extension 18 is locked to a piston element 33, which element comprises two plates with packing 34 therebetween and secured together by means of bolts or rivets 35. Piston element 33 is thus mounted in sealed relation with the inner wall of cylinder 29, and is slidable therein. Alternatively, piston element 33 may comprise a conventional arrangement of a piston member having a sealing piston ring mounted in a groove extending therearound. Also, fuel line extension 18 is flared at its extreme rearward end, as shown at 36, which flare is adapted to cooperate with a tapered projection or seat 37 on wall 31.

An intake fuel line 38 joins to a conduit 39 which extends into cylinder 29 on one side of piston 33, and an atomizing steam line 40 is likewise joined to conduit 39. Burner 8 is similarly providedwith an intake fuel line 38 and an atomizing steam line 40'.

Control valves

41 and 41 are provided in

intake fuel lines

38 and 33, respectively, and control valves 42 and 42' are provided in the atomizing

steam lines

40 and 40 respectively. The valves of each burner, which valves are preferably pneumatically actuated, are interlocked and controlled by means including a pressure line 43 extending to a central control panel 44, the arrangement being such that the valves controlling one burner are automatically closed when the valves controlling the other burner are open, and vice versa. While pneumatic controls are believed to be preferable, any conventional control means can be used. In addition, a conduit 45 extends from atomizing steam line 40' of burner 8 to cylinder 29 on that side of piston 33 which is opposite from conduit 39. Similarly, a conduit 46 extends from atomizing steam line 40 of burner 9 into the corresponding end of the cylinder on burner 8.

Also, a coolant intake conduit 47 extends into the lower portion of jacket 12 to the forward end thereof, and a coolant exhaust conduit 48 extends outwardly from the top portion of jacket 12. With this arrangement, the coolant, which may be water or any other suitable fluid, is introduced into the cooling jacket near the burner nozzle where the greatest cooling elfect is needed.

It will be appreciated that the burners are of considerably greater lengthwise extent than appears from Fig. 2 which is a fore-shortened view as indicated by the break lines. That portion of the burner which is broken away is merely a continuation of the illustrated structure, and the true relative length of the burners is more accurately shown in Fig. l.

The operation and control of this burner is as follows.

As illustrated, burner 9 is in firing position and burner 8 is shut down. Thus,

valves

41 and 42, which operate in unison, are open, and

valves

41 and 42, which also operate in unison, are closed. Assume now that controller 44 operates or is operated to open valves 41' and 42' and

close valves

41 and 42. When this occurs, fuel and atomizing steam will pass to burner 8 through conduits 38 and 40', causing said burner to fire, while burner 9 will cease firing and become inactive. At the same time, some of the atomizing steam passing through conduit 40 will be diverted through conduit 45 and into cylinder 29 where it will create a pressure differential moving piston 33, and consequently fuel line extension 18, fuel line 16 and mount 14, rearwardly, thus retracting or withdrawing nozzle 17 into the cooling jacket 12, as shown by broken lines in Fig. 2. It will be appreciated that the parts are arranged so that nozzle mount 14 is never completely withdrawn from bushing 13. Piston 33 will continue its rearward movement under the influence of atomizing steam entering cylinder 29 through conduit 45 until flare 36 firmly engages tapered seat 37, as shown in broken lines in Fig. 2, whereupon fuel line 16 is closed. At the same time, nozzle 17 is withdrawn or retracted into burner 9 whereby it is protected against injury from the intense heat of the furnace. Also, since nozzle 17 is retracted into burner 9, there is less danger of it becoming plugged by the furnace exhaust, and recess 15 on the exterior surface of nozzle mount 14 tends to clean the same during retraction.

When controller 44 reverses the valves to shut down burner 8 and cause burner 9 to begin firing, the incoming atomizing steam and fuel from

conduits

40 and 38 reverse the pressure difierential within cylinder 29 to move piston 33 and consequently fuel line 16, extension 18, and nozzle mount 14, forwardly to the position illustrated in solid lines in Fig. 2. Any atomizing steam acting against the forward side of piston 33 is dissipated through conduit 45, conduit 40, and the fuel line and nozzle of burner 8 While said burner nozzle is being retracted. At the same time, some of the atomizing steam passing through conduit 40 is diverted through conduit 46 to retract the nozzle of burner 8 in a manner identical with the retraction of nozzle 17 in burner 9. .While the nozzle of burner 8 is retracted quickly, there is sufficient time for steam in cylinder 29 to be dissipated through conduit 45 in the manner aforesaid.

Thus it is apparent that the instant invention fully accomplishes the aforesaid objects. A burner is provided wherein its direction of firing is variable between wide limits while the burner itself remains stationary. In addition, compact and relatively simple means are provided for automatically using the atomizing steam of the active burner to retract the nozzle of the inactive burner. Further, the burner nozzle possesses self-cleaning characteristics and is arranged to avoid being soiled by the furnace exhaust, and means are provided for sealing the fuel line of the inactive burner. All of these desirable features are provided in a relatively inexpensive structure which is compact and completely reliable in operation.

It will be appreciated that the present invention is not limited to the use of atomizing steam, and that other fluids could be substituted in place thereof. Also, any conventional means can Issued to control

valves

41, 41', 42, and 42. Also, if desired or necessary, releasable locking means can be provided to lock wheel 25 against turning movement relative to jacket 12 during retraction of the nozzle, which locking means can take the form of a lever hingedly connected to jacket 12 and adapted to engage one of a plurality of slots on wheel 25, said lever being provided with an anchor connection on member 28. Further, various modifications of the structural details disclosed herein will become apparent to those skilled in the art, and it is intended that the instant invention be limited solely by the appended claims.

Having fully disclosed the instant invention, and completely described the operation thereof, what is claimed as new is as follows.

I claim: r

1. In combination with a furnace, multiple burners each having a retractable nozzle member and means including fluid pressure responsive means operatively connected thereto for retracting said nozzle member, means including a conduit operatively connected with each burner for supplying a fluid fuel component thereto, means controlling the passage of fluid through each of said conduits for supplying fluid alternately to either of said burners whereby one of said burners is inactive when another thereof is actively firing, means projecting the nozzle member of the active burner into said furnace, and branch conduit means placing the conduit of each burner in communication with the fluid pressure responsive means of the other burner for diverting some of the fluid passing through the conduit of the active burner to the fluid pressure responsive means of the inactive burner to retract the nozzle means thereof.

2. In combination with a furnace, multiple burners each having retractable nozzle means and means including fluid pressure responsive means operatively connected thereto for projecting and retracting said nozzle means, means including a conduit operatively connected with each burner for supplying a fluid fuel component thereto, control means including valve means associated with each of said conduits for supplying fluid alternately to either of said burners whereby one of said burners is inactive when another thereof is actively firing, the conduit of each burner being operatively associated with the fluid pressure responsive means thereof to cause the latter to project the nozzle means of that burner into said furnace when that burner is active, and branch conduit means communicating with said conduits between said valve means and said fluid pressure responsive means and placing the conduit of each burner in communication with the fluid pressure responsive means of another burner for diverting some of the fluid passing through the conduit of the active burner to cause the pressure responsive means of the inactive burner to retract the nozzle means thereof.

3. In combination with a furnace, at least two burners each having retractable nozzle means and. means including fluid pressure responsive means operatively connected thereto for projecting and retracting said nozzle means, means including a conduit operatively connected with each burner for supplying a fluid fuel component thereto, means controlling the passage of fluid through each of said conduits for supplying fluid alternately to either of said burners whereby one of said burners is inactive when the other thereof is actively firing, the conduit of each burner operatively communicating with the fluid responsive means thereof to cause the latter to project the nozzle means of that burner into said furnace when that burner is activelyfiring, and branch conduit means placing the conduit of each burner in communication with the fluid pressure responsive means of the other burner for diverting some of the fluid passing through the conduit of the active burner to the fluid pressure responsive means of the inactive burner to retract the nozzle means thereof.

4. A furnace burner comprising, a cooling jacket, a nozzle member completely retractable into said cooling jacket, a cylinder defining a fluid pressure chamber, a fuel line operatively connected with said nozzle member for supplying fuel thereto and extending therefrom into said chamber, piston means movable in said chamber and operatively connected with said fuel line to alternately project said nozzle member forwardly of said jacket and retract said nozzle member into said jacket along an axis extending generally lengthwise thereof upon movement of said piston means in opposite directions in said chamber, means for supplying fluid under pressure to said chamber on one side of said piston means for moving the same to completely retract said nozzle member into said cooling jacket, said fuel line extending through said piston means and having a normally open inner end on the other side thereof, means for supplying a fluid fuel component to said chamber on said other side of said piston means for passage through said fuel line to said nozzle member and for moving said piston means to project said nozzle member forwardly of said jacket for firing, and means carried by said cylinder in said chamber for engaging said inner end of said fuel line to close the same when said nozzle member is retracted, said fuel line having a fuel ejecting conduit portion in said nozzle member inclined relative to said axis, and means for rotating said nozzle member and said conduit portion about said axis to vary the direction of firing of said burner.

5. A furnace burner comprising, casing means, a nozzle member movable within said casing means along a pre determined axis extending generally lengthwise thereof for retraction into said casing means when the burner is inactive and projection forwardly thereof to an exposed position when the burner is actively firing, a fuel ejecting conduit extending through said nozzle member in inclined relation to said axis, said conduit being operatively connected to said nozzle member for movement therewith, means for supplying a fuel component to said nozzle conduit, means for retracting and projecting said nozzle member and conduit along said axis relative to said casing means, and means for rotating said nozzle member and conduit about said axis for varying the direction of firing of the burner.

6. A furnace burner comprising, casing means, a nozzle member mounted for movement relative to said casing means along a first axis to retract said nozzle member into said casing means when the burner is inactive and project said nozzle member forwardly of said casing means to an exposed position when the burner is active, said nozzle member including a fuel ejecting conduit extending long a second axis inclined relative to said first axis, means for supplying a fuel component to said fuel ejecting conduit, means for retracting and projecting said nozzle member and fuel ejecting conduit along said first axis, and means for rotating said nozzle member and fuel ejecting conduit about said first axis to vary the direction of firing of the burner.

7. A furnace burner comprising, casing means, a nozzle member arranged to project forwardly of said casing means to an exposed position when the burner is firing and retractable into said casing means along a predetermined axis extending generally lengthwise thereof when the burner is inactive, a fuel conduit operatively connected with said nozzle member for movement therewith and having an outer end fuel ejecting conduit portion in said nozzle member canted relative to said axis for ejecting fuel from said nozzle member at an acute angle to said axis, means for moving said nozzle member along said axis to project and retract said nozzle member relative to said casing means, means for supplying a fuel component to said conduit for passage therethrough to said fuel ejecting portion, and means for rotating said nozzle member and said fuel ejecting conduit portion about said axis to vary the direction of firing of the burner.

8. A furnace burner as set forth in claim 6, wherein said nozzle member is supported by bushing means on said casing means, and wherein said nozzle member has recessed side portions of generally hour glass form.

9. In combination with a furnace, burners arranged adjacent the oppositeends of said furnace, each of said burners having retractable nozzle means, a fluid pressure chamber, fuel line means operatively connected with said nozzle means and extending therefrom into said chamber, and piston means movable within said chamber and operatively connected with said fuel line means to alternately project and retract said nozzle means, means including conduit means operatively connected with each burner for supplying a fluid fuel component to said chambers on one side of said pistons for transmission through said fuel line means to said nozzle means and for moving said pistons to project said nozzle means into said furnace, valve means controlling the passage of fluid through said conduit means for supplying fluid alternately to either of said burners, whereby one of said burners is inactive when another thereof is actively firing, branch conduit means placing the conduit means of each burner in communication With the chamber of another burner on the other side of the piston means therein for diverting some of the fluid passing through the conduit means of the active burner to move the piston means of the inactive burner and retract the nozzle means thereof, and means for reversing the firing of said burners.

10. A furnace burner comprising, casing means, a nozzle member movable within said casing means along a predetermined axis extending generally lengthwise thereof, a fuel ejecting passage extending through said nozzle member in inclined relation to said axis, means for retracting said nozzle member along said axis and into said casing means when the burner is inactive, means for supplying a fuel component to said fuel ejecting passage, means for projecting said nozzle member forwardly of said casing means along said axis to an exposed firing position in response to such supplying of fuel to said fuel ejecting passage, and means for rotating said nozzle memher and fuel ejecting passage about said axis to vary the direction of firing of the burner.

11.;A furnace burner comprising, a retractable nozzle movable along a predetermined axis extending generally lengthwise of the burner, a fluid pressure chamber, a fuel line operatively connected with said nozzle and extending therefrom into said chamber, said fuel line communicating at said nozzle with a fuel ejection passage extending through said nozzle in canted relation to said axis, piston means movable in said chamber and operatively connected with said fuel line to move said nozzle along said all;

;. s upon movement of said piston means in opposite LlllzcllODS in said chamber, means for supplying fluid under pressure to said chamber on one side of said piston means for moving the same to retract said nozzle along said axis, said fuel line communicating With said chamber on the other side of said piston means, means for supplying a fluid fuel component under pressure to said chamber on said other side of said piston means for transmission through said fuel line to said fuel ejection passage and for moving said piston means to project said nozzle along said axis, and means for rotating said nozzle and fuel ejection passage about said axis to vary the direction of firing of the burner.

References Cited in the file of this patent UNITED STATES PATENTS 1,085,120 Gibbs Jan. 27, 1914 1,160,806 Wuestner Nov. 16, 1915 1,484,888 Johnson .d Feb. 26, 1924 1,646,703 Mulholland Oct. 25, 1927 1,838,753 Farrington Dec. 29, 1931 2,047,523 Scranton et a1. July 14, 1936 2,382,483 Holden Aug. 14, 1945 2,395,276 Jordan Feb. 19, 1946 2,446,511 Kerry et al Aug. 3, 1948 2,540,416 Asscher Feb. 6, 1951 2,672,191 Campbell et al Mar. 16, 1954