US 3219094 A
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Description (OCR text may contain errors)
Nov. 23, 1965 R. F. LEMPA f V3,219,094
` INDUSTRIAL BURNER Filed Jan. 7, 1964 3 Sheets-Sheet 1 ATTORNEY R. F. LEMPA INDUSTRIAL BURNER Nov. 23, 1965 Filed Jan. 7, 1964 3 Sheets-Sheet 2 NVENTOR. ROMAN F. LEMPA S SS Q mm m- ATTORNEY.
Nov. 23, 1965 R. F. LEMPA 3,219,094
INDUS TR IAL BURNER Filed Jan. '7, 1964 5 Sheets-Sheet 3 F I G. 5
INVENTOR. ROMAN F. LEM PA ATTORNEY.
United States Patent 3,219,094 INDUSTRIAL BURNER Roman F. Lempa, Philadelphia, Pa., assignor to Selas Corporation of America, Dresher, Pa., a corporation of Pennsylvania Filed Jan. 7, 1964, Ser. No. 336,164 6 Claims. (Cl. 158-7) The present invention relates to industrial gas burners, and more particularly to a burner in which the llame and combustion gases move away from the burner at a relatively low velocity.
In some burner applications it is desirable to have a relatively quiet furnace atmosphere so that the material being heated may be close to the burners without being disturbed by the flow of gases from them. It is for such a use that the burner of this invention was designed.
It is an object of the present invention to provide a burner having a low forward velocity of the combustion gases. It is a further object to provide a burner which may be used with preheated air, and with means whereby the amount of air supplied to the burner can easily be regulated. It is a still further object of the invention to provide a burner in which the forward Velocity of the supplies of fuel and air are substantially dissipated pn'or to the time they can move from the burner block into the space being heated.
In practicing the invention, the fuel and air are mixed just prior to being introduced into a combustion tunnel in a burner block located in a furnace wall. This tunnel is so shaped, relative to the direction of travel of the fuel mixture, that the forward velocity of the mixture is substantially reduced. The air supply portion of the burner forms what is actually a portion of a supply manifold for all of the burners of a furnace. Means is provided to regulate the supply of air actually used by the burner, which means is located between the supply portion and the point of exit of the air from the burner.
The various features of novelty which characterize my invention are pointed out with particularity in the claims annexed to and forming a part of this specification. For a better understanding of the invention, however, its advantages and specific objects attained with its use, reference should be had to the accompanying drawings and descriptive matter in which `I have illustrated and described a preferred embodiment of the invention.
In the drawings:
FIG. 1 is a section through the burner,
FIG. 2 is a section taken on line 2-2 of FIG. 1,
FIG. 3 is a view of the front of the burner taken from the right of FIG. 1,
FIG. 4 is a view of the back of the burner taken from the left of FIG. 1, and
FIG. 5 is a section of a modified form of burner.
Referring to the drawings, there is shown a furnace wall 1 of usual construction having a backing of sheet metal 2 in which the burner is located. The burner includes a body 3 in the form of a metal casting which is bolted to backing plate 2 by means of bolts 4 which pass through a flange 5 on the body. The body 3 is a hollow casting which has essentially a first passage 6, that extends perpendicular to the furnace wall, and a second passage 7, that extends parallel to the furnace wall. The burner also includes a burner block 8 which forms a portion of the furnace wall, with one end of the block being flush with its inner face. In assembling the burner in the wall, the casting 3 is first bolted to` the back plate 2 and the brick work of the wall, including the burner block, is built up around the casting.
The burner block has formed therein a combustion tunnel 9 which is substantially square in shape and decreases in area in steps 11 as the tunnel recedes from the 3,219,094 Patented Nov. 23, 1965 ICC face of the furnace wall. The base of this tunnel is provided with an opening 12 that extends to the rear of the burner block and receives a portion of casting 3 at the front of the first passage 6. Extending through this passage is a gas pipe 13 which is threaded into a cap 14 that is attached to the back of casting 3 by means of bolts 15. Mounted on the opposite end of pipe 13 is a refractory fuel and air distributing block 16 which extends beyond the burner body to be received in the opening 12 at the base of the combustion tunnel. This block is provided with a centrally located bore 17 into which the end of pipe 13 extends. The pipe is sealed to the bore in any suitable fashion to prevent gas from leaking around the end of the pipe. One means of accomplishing this seal is a diaphragm 18 which is attached to and extends radially from the pipe and has an axially extending ange that is cemented into a groove formed into the block.
Each corner of block 16 is provided with an air passage 19 that starts from passage 6 parallel to opening 12. The other ends of these air passages are bent as shown at. 21 so that the air discharged through them is substantially perpendicular to the corresponding side of the step 11 at the base of the combustion tunnel. The blo-ck 16 is also provided with gas passages 22 that extend from the center bore 17 into the air passages at a point adjacent to their exit ends. It is noted that the gas passages enter the air passages in a direction that is substantially perpendicular to the iiow of air.
The flow of air to the air passages is controlled by an air shutter which is mounted on a tube 23 that loosely surrounds gas pipe 13. The shutter includes a circular disc 24 attached to the end of tube 23 by means of a nut 28. This disc has a series of openings 25 formed in it which cooperate with openings 27 in a stationary plate 26 that is received, as shown best in FIGS. 1 and 2, in the forward end of passage 6 in the casting 3. The rear end of tube 23 extends through a ceramic block 29 that blocks the rear end of passage 6. Tube 23, to which the shutter disc 24 is attached may be adjusted from the exterior of the furnace. To this end, a disc 31, having a radially extending tab 32, is mounted on the outer end of tube 23. By reference to FIG. 4, it will be seen that the disc 31 is of such a size that it will be received within a circle circumscribed by the bolts 15 which hold cap 14 in place. Gaskets 33 are provided at opposite sides of disc 31. By loosening the bolts 15, tab 32 can be moved to adjust disc 24 relative to plate 26, thereby adjusting the size of the air passage which is defined by the relative position of openings 25 and 27. After the shutter disc has been adjusted, bolts 15 are tightened to hold it in place. Since the air used by the burner may sometimes be preheated, it is advisable to insulate the gas pipe somewhat from the air. To this end, a sleeve.34 is placed over tube 23 and a short sleeve 35 is placed over the front end of the tube. It is noted that the pressure of the gas supplied to the burner may be measured by removing plug 36 from the cap 14 and the air pressure may be measured by removing a plug 37. The pressure of the air is applied from around sleeve 35 through the interior of tube 23 to the interior of cap 14.
The second passage 7 of the burner body, which extends parallel to and between the faces of the furnace Wall, forms, with similar passages of the adjacent burners, a manifold through which the air is supplied to the burner. Since these passages are built into the furnace wall, they will be heated somewhat by the flow of heat through the furnace wall and preheat of the air will be retained by the normal insulation of the furnace wall. It is intended that the ends of passages 7 shall be connected to the ends of adjacent passages 7 of adjacent burners by wrapping a strip of suitable material, such as asbestos tape 38, around the joints of the adjacent burner bodies. This tape will be held into position by a suitable binder 39. As indicated above, the burner bodies are attached to the metal plate 2 and they would be connected to each other prior to the time the furnace wall is built up.
In the operation of the burner, air, which may or may not be preheated, is supplied to the manifold formed by the connected passages 7 of the burners, and fuel gas is supplied through pipe 13. Ordinarily the gas and air supplied to all of the burners of a furnace will be properly proportioned by a ratio controller. The air shutter disc 24 will usually be adjusted to compensate for variations in individual burners and their location in the furnace, and will then not be disturbed. The air to each burner, however, can be adjusted solely by air shutter 24 if it is desired.
Air will flow through passages 19 in block 16 to be directed substantially perpendicularly against the opposing side of the nearest step 11 of combustion tunnel 9. Gas is discharged through passages 22 into the air stream at right angles to the air stream so that thorough mixing will take place. The direction of flow of the mixture against the sides of the tunnel prevents swirling and substantially reduces its velocity so that combustion takes place with a minimum forward movement of products of combustion from the tunnel into the furnace chamber.
In FIG. of the drawing, there is disclosed another embodiment of the invention which includes the same basic features of the embodiment disclosed above. Referring to that figure, there is shown a burner block 41 which is built into a furnace wall 42. The front portion of the block, which is ush with the furnace wall, is provided With a combustion tunnel 43 having steps 44 on it as in the previously described embodiment. In this case, however, a projection 45 is formed at the base of the tunnel. This projection is provided with four air passages 46, each of which is directed perpendicularly to one of the faces of the tunnel. The inner ends of these passages are connected with a central air passage 47.
Gas is supplied to the burner through a gas pipe 48 that is rigidly mounted in a suitable opening in a backing plate 49 that is bolted to the metal casing of the furnace wall. The gas pipe passes through a refractory cylinder 51 that is located in the furnace wall in axial alignment with passage 47. The gas pipe passes through this passage to a point radially inward of passages 46 where the pipe is provided with hollow projections 52 extending into these passages so that gas may flow from pipe 48 into passages 46 to mix with the air therein. Since it may be desirable to use preheated air with the burner, the gas pipe is surrounded with a ceramic coating 53 in order to prevent undue heating of the pipe and the gas traveling therethrough.
Block 51 is provided with a cut-out portion S4 to form an air passage between passage 47 and an air manifold 55 that is built into the furnace wall and parallel to the front and rear faces thereof. The amount of air flowing from manifold 55 to the burner can be varied by rotating block 51 and thereby varying the effective area of the portion 54 of the air passage. This is accomplished by means of a sleeve 56 rotatably supported on the gas pipe which has a pin 57 extending into the cylindrical block 51. The sleeve is rotated by gears 58 and 59, the latter of which is mounted to be turned with a handle 61 of extending outwardly from the back plate 49.
In the operation of this burner, air and gas are supplied to the burner in a manner previously described. The amount of air can be adjusted as desired by rotating handle 56 thereby to rotate cylindrical block 51, the cutout portion 54 of which acts as a valve in the air passage. Air and gas are discharged directly against one of the walls of the tunnel 43 where the forward velocity is broken up. The air and gas burn in the combustion tunnel and the products of combustion move forward from the tunnel only with that velocity that is required as a result of the amount of fuel and air being burned.
From the above, it will be seen that the burner ofl this invention produces a forward flame velocity that is relatively loW so that there will be a minimum of turbulence in the furnace atmosphere. In addition, the air for a burner or group of burners in a furnace is supplied through a manifold that is built into the furnace wall and the amount of air that is supplied to each burner can be adjusted by a valve forming a part thereof which is in the furnace wall.
While in accordance with the provisions of the statutes I have illustrated and described the best form of embodiment of my invention now known to me, it will be apparent to those skilled in the art that changes may be made in the form of the apparatus disclosed Without departing from the spirit and scope of the invention set forth in the appended claims, and that in some cases certain features of my invention may be used to advantage without a corresponding use of other features.
What is claimed is:
1. In a burner, the combination of a burner block having a tunnel therein substantially square in section, the area of said tunnel diminishing in steps from the face of said block toward the rear thereof, means received in the small end of said tunnel having a plurality of passage means formed therein through which air and gas travel to said tunnel, said air passage means being formed so that each one directs air substantially perpendicularly and directly against one side of said tunnel adjacent to the point of air entry into said tunnel, said gas passage means each discharging into an air passage at an angle thereto adjacent to the point where the air passage discharges into the tunnel, means to supply air to said air passage means, and means to supply gas to said gas passage means.
2. The burner of claim 1 including valve means located in said air supply means upstream of and adjacent to said block to control the supply of air to said air passages, and means to adjust said valve means.
3. In a burner, a burner block, said block being provided with a combustion tunnel substantially square in shape and diminishing in area in steps from one face of said block, gas and air distributor means at the small end of said tunnel, said means being provided with passages for air each of which terminates substantially perpendicularly to one side of said tunnel adjacent to its small end and gas passages each of which terminates in one of said air passages and substantially perpendicular thereto, a gas pipe to supply gas to said gas passages, means including a portion surrounding said gas pipe to supply air to said air passages, and an air valve in said surrounding portion to control the flow of air to said air passages.
4. In an industrial burner, a burner block having a front face and a back face, a combustion tunnel of substantially square shape extending inwardly from said front face in steps of diminishing area, said block being provided with an opening extending from the base of said tunnel to the rear face of said block, means to distribute gas and air to said tunnel received in said opening, said distributing means being provided with air passages each of which terminates in a direction to discharge air substantially perpendicularly to and against a side of said tunnel adjacent to the small end thereof, said distributing means also being provided with gas passages each of which is directed to discharge gas substantially perpendicularly into an air passage adjacent to the exit of said air passage, and means to supply air and gas to said passages respectively.
5. In combination, a furnace Wall of predetermined thickness having a front face and a rear face, a burner block of less thickness than said wall in said wall flush with said front face, said block being provided with a combustion tunnel diminishing in area as it recedes from said face, means forming an air manifold in said wall and extending parallel to said faces between said block and rear face and directly communicating with the small end of said tunnel, distributing means for gas and air positioned in the small end of said tunnel, means forming air' passages extending through said distributing means to said tunnel, an air valve across the area of communication between said manifold and the small end of said tunnel, operating means extending from the rear face of said wall across said manifold to said air valve to operate the same, a gas supply pipe extending through said wall to said distributor means, and means forming gas passa-ges in s-aid distributor means extending from said gas pipe to the airpassages in said distributor means.
6. In a burner adapted to be placed in a furnace Wall between the front and back faces thereof, said burner including a burner block having a combustion tunnel therein, said tunnel being substantially square in shape and diminishing in area in steps from the discharge end thereof, said block also being provided with an opening extending axially into the small end of the tunnel, gas and `air distributing means received in said opening, said distributor means being provided with a plurality of air passages, each of which terminates in a direction to dis- References Cited by the Examiner UNITED STATES PATENTS 2,380,463 7/1935 Poole 158-115 2,474,313 6/ 1949 Hess 158-7 2,561,793 7/1951 Furczyk 158-7 X 3,007,515 11/1961 Furdock 158-76 FOREIGN PATENTS 214,378 4/ 1924 Great Britain.
20 I AMES W. WESTHAVER, Primary Examiner.
MEYER PERLIN, Examiner.