US3139138A

US3139138A - Furnace burner system

Info

Publication number: US3139138A
Application number: US560217A
Authority: US
Inventors: Frederick S Bloom
Original assignee: Bloom Engineering Co Inc
Current assignee: Bloom Engineering Co Inc
Priority date: 1956-01-19
Filing date: 1956-01-19
Publication date: 1964-06-30
Anticipated expiration: 1981-06-30

Description

June 30, 1964 F. s. BLooM 3,139,138

FURNACE BURNER SYSTEM Filed Jan. 19, 1956 4 Sheets-Sheet 2 26 3g 26 5.9, is 36" .gg 35 INVENTOR FREDERICK S. BLooM June 30, 1964 F. s. BLooM FURNACE BURNER SYSTEM 4 Sheets-Sheet 5 Filed Jan. 19, 1956 INVENTOR Frederick S. Bloom 1f fang/9M June 30, 1964 F. s. BLOOM FURNACE BURNER SYSTEM 4 Sheets-Sheet 4 Filed Jan. 19, 1956 w //U/O//H/ INVENTOR Frederick S. Bloom @wrm United States Patent O 3,139,138 FURNACE BURNER SYSTEM Frederick S. Bloom, Mount Lebanon Township, Allegheny County, Pa. Bloom Engineering Company, Inc., S57 W. North Ave., NS., Pittsburgh 33, Pa.) Filed Jan. 19, 1956, Ser. No. 560,217 14 Claims. (Cl. 158-11) This invention relates to a furnace burner system, and more particularly to a system for obtaining high thermal release with dilferent fuels of widely varying combination characteristics from the same burner nozzle in high temperature furnaces. Further, burners of my invention are adapted not only for use as combination oil-and-gas burners, but also as burners for fuel gas alone or for fuel oil alone. And, separation of the stream of fuel and of the stream of combustion air respectively may be provided until such streams have been discharged from such new burner.

In Bloom et al. application Serial No. 158,904, filed on April 28, 1950, and under common ownership with the present application, there is disclosed a burner system which has proved successful in achieving high thermal release in small furnaces for heating metal billets, with either gas or oil as fuel. The burner there illustrated has connections for receiving combustion air, fuel gas, fuel oil, and compressed air or steam for atomizing the fuel, and has a burner cap nozzle extending into a cupped opening in a refractory block. A mixing chamber in the nozzle receives air and fuel from the supply passages, and discharges a complete combustible mixture through a series of radial nozzle passages into the refractory depression to burn therein. When gas or oil of relatively slow-burning characteristics is used this burner has proved satisfactory; e.g., when burning light fuel oil and natural gas. In some cases, however, it is desirable not only to interchange liquid and gaseous fuels but also to use fuels of Widely varying combustion characteristics, including relatively fast-burning coke oven gas or hydrogen, without danger of backring into the interior of the burner.

In accordance with my present invention the burner is made adjustable to control the place where the fuel and combustion air are initially brought together so that when fuels of different burning characteristics are used adjustment can be made to delay mixing the fuel and air suiiiciently to avoid backfire while still insuring complete burning around the nozzle in the surrounding refractory depression. When using slow-burning fuels the effective axial length of the mixing chamber is enlarged to allow for maximum premixing before the combined air and fuel is released from the radial openings through the nozzle into the refractory depression. When very fast-burning fuels are used the axial length of the mixing chamber is decreased to prevent mixing the air and fuel until shortly before or after the fuel and air enter the radial passages. In one embodiment of the invention a plain cylindrical sliding sleeve is used for this purpose, with the gaseous or liquid fuel being fed through the interior of the sleeve toward the tip of the nozzle while the combustion air is fed around the outside of the sleeve to join the fuel at the extremity of the sleeve nearest the tip of the nozzle. This provides a very simple construction, since the main body of the nozzle merely comprises a cylindrical wall and an end cap forming the terminal end of the mixing chamber, with a plurality of radial openings which can easily be drilled through the cylindrical wall adjacent the cap. In another embodiment of the invention the sliding sleeve is anged outwardly to slide against a cylindrical wall of the nozzle across the inner ends of two rows of radial outlet openings through the nozzle, one set of openings being nearer the tip of the nozzle than the other, so that ice the sleeve is adjustable to direct all of the fuel through the row of radial openings nearest the nozzle tip while the combustion air is directed through the other row of radial openings, either entirely (with mixing occurring after the fuel stream and the combustion air stream are separately discharged from the burner cap nozzle) or with a portion of the air also directed .into the radial opening-s through which the fuel is directed. In this way the formation of any mixture or of a completely combustible mixture is delayed until after the mixture passes into the refractory depression, but with such rapidly burning fuels as coke oven gas lack of complete premixture of air and gas before entering the refractory depression does not prevent complete combustion in the depression. When using slower burning fuel-s the flanged sleeve is drawn back out of sliding engagement with the relatively small diameter outer end of the nozzle, and the fuel and air are fully mixed in the nozzle before passing through the radial openings into the refractory depression. This form of burner is similarly easy to make and operate. In the case of both the straight and anged types of sleeves, adjustment of the sleeve for different /pes of fuels can be made without cutting off the burner ame.

Other details, objects and advantages o f the invention will become apparent from the following description and from the accompanying drawings, in which I have shown for purposes of illustration only, certain present preferred embodiments of my invention. In the drawings:

FIGURE 1 shows a sectional view through the axis of a burner in accordance with the invention, mounted in a furnace;

FIGURE 2 is a fragmentary section on the line II-II in FIGURE 1;

FIGURE 3 is a section on the line III-III in FIG- URE l;

FIGURE 4 is a view of a modified form of burner in accordance with the invention, viewed as in FIGURE l but breaking away some identical corresponding portions of the burner and refractory wall;

FIGURE 5 is a front end view of the outer shell of the burner shown in FIGURE 4;

FIGURE 6 is a section on the line VI-VI in FIG- URE 5;

FIGURE 7 is a sectional view through the axis of a further modified form of a burner made in accordance with my invention, mounted in a furnace;

FIGURE 8 is a sectional view of the front portion of a burner like the burner shown in FIGURE 7 in a burner port block with a variant recess therein;

FIGURE 9 is a sectional view of an inner portion of a still further modified form of a burner made in accordance with my invention, mounted in a modied burner port block; and

FIGURE l0 is a sectional View of another modified form of a burner of my invention, mounted in a furnace.

Referring now particularly to the drawings and considering lirst the embodiment shown in FIGURE 1, a refractory burner block 10 forms part of the wall 11 of a furnace for heating metal billets and the like, or other high temperature heating service. A cup-shaped depression 12 is formed in the block 10 to face the interior of the furnace, with a peripheral cylindrical surface 13 and an inner conical surface 14. The outer metal shell body 15 of a burner 16 extends through the block 10 coaxially with the conical refractory surface 14, with cylindrical rear wall 17 of relatively large diameter, a conical intermediate shoulder 18, and a cylindrical front wall 19 of reduced diameter. The rear wall 17, the shoulder i8 and the rear end of the front wall 19 are closely surrounded by the block 10, and the balance of the front wall 19 projects into the depression 12 to form the nozzle tip of burner 16. A cap 21 closes the end of the vwall 19 to form a mixing chamber 22 therein, and two rows of radial openings 23 are drilled through the outer end of wall 19 parallel with the adjacent portions of the conical refractory surface 14. The interior surface 24 of cap 21 may be initially formed as a cone parallel with the conical refractory surface 14, and then indented with semicircular radial channels by drilling the front row 25 of openings 23with their central axes extending flush with the conical surface 24 (FIGURES 1 and 3). However, such channels are not necessary and such drilling is difficult, and accordingly the front row of openings are preferably drilled tangential to the inner conical surface of the cap without cutting into the cone (as shown at 44 in FIGURE 6). The 'rear row 26 of openings 23 comprise an equal number of openings in staggered relation to the front openings 25 and axially offset further from the cap 21. The total number of openings 23 is forty in the embodiment being described, and this number is preferably high in order to have relatively small. diameter openings 23 for purposes of opposing backfire.

All of the combustion air whenever air is not being supplied through the oil atomizer subassernbly in the combination oil and gas burner illustrated, or all of the balance of combustion air whenever it is required to burn the fuel completely,l is supplied under pressure vthrough a conduit 27 and manifold 28, and thence around the outside ofv a fixed tube 29 and sleeve 39, and'along the inside of

walls

17 and 19 and shoulder 1S, into the mixing chamber 22. The rear end of tube 29 is secured to a removable plate 31 in the rear Wall of manifold 28. The rear end of sleeve is axially slidable within the tube 219. A pair of stiff control wires 32 are welded to opposite sides of the projecting end of sleeve 39, and extend slidablythrough the rear wall of manifold 28 to provide convenient handles for shifting the sleeve 30, even when the burner is in operation. The forward end of sleeve 30 isV adjustable between a retracted position to the rear of shoulder 18 and an extended position limited by abutment with the channeled inner surface of cap 21. The tube 29 and sleeve 30 are concentric with

walls

17 and 19 and shoulder 18, and the sleeve 30 is of smaller diameter than wall 17 in order to allow combustion air to reach the radial openings 23 even when the sleeve 3i) is fully extended.

Fuel is supplied through a series of concentric tubes into the projecting end of sleeve 3i), and thence into the i Y i the usual light (eg. grade 2) fuel oil, and the gas travels `axially toward the cap 21 while the shoulder 1S deiiects the combustion air toward the burner axis, so that the air thoroughly mixes with the gas in the chamber 22 before entering the radial openings Z3. When a relatively fast-burning, high hydrogen-content gas such-as coke oven gas is used, the sleeve 38 is advanced approximately to the position shown in full lines in FIGURE l, with the outer extremity of the sleeve 39 disposed in the conical plane through the axes of the rear row 26 of radial openings 23. In this advanced position the sleeve 3f) prevents the air and gas from mixing until just before entering the radial openings 23, and this has been found in practice to prevent backfire in high temperature furnaces burning coke oven gas to heat steel billets to temperatures of at least 2350 F. v

A modified form ofburner in accordance with the invention is shown'in FIGURES Ll -6. This burner 16 is similarly mounted in an identical block lil' with conical depression 14. The burner 16' has outer walls 17' and 19', shoulder 18', two rows 25' and 26' of radial outlet openings 23', and supply connections for fuel and air,

corresponding to the identical elements 17-19, 23, 24, 26-29 and 31-38 shown inA FIGURE 1, the only structural differences from what is shown in FIGURE 1 lying 'n1 the front end of the sleeve and in the inner surface of the nozzle cap. The sleeve 4t) in FIGURE 4 has its rear end mounted in the same way as the sleeve 3G in FIGURE l, but has its projecting end belled out in a circular flange 41 which is slidable along the cylindrical interior surface 42 of the nozzle wall 19. `The nozzle cap 43 at the end of wall 19' has a plain conical interior surface 44 parallel to the conical refractorysurface 14' and tangential with the front radial openings 25' through the nozzle wall 19' (FIGURE 6). The sleeve flange 41 is substantially thinner than the diameter of the openings 23' and extends parallel to the conical surface 44 in v order to cooperate with the surface 44 in directing fuel mixing chamber 22. The innermost tube 33 receives n fuel oil through a rear connection 34 and delivers it through a central axial opening in an atomizer nozzle 35 centered in spaced relation within s'leeve30. Atomizing steam (or compressed air for atomizing) is supplied under a higher pressure through an Vopening 36 into a connection member 37 and thence between the tube 33 and a surrounding tube 38 to nozzle 35, which sprays the steam and oil in a cone of atomized droplets toward the shoulder 18 into the inside of burner cap 21. When oil is in the fuel the projecting end of sleeve 30 is retracted back of the forward end of wall 17, and the combustion air crosses the stream of the atomized oil from nozzle 35 and carries it into the mixing chamber 22, where the oil and air are well mixed before entering the radial openings 23.

Gaseous fuel is supplied through an opening 39 into an annular space between a tubular rear extension 31a of plate 31 and tube 38. The rear end of this annular space is closedV by connection member 37 screwed between the tube 38 and the rear end of the extension 31a. Gaselous fuel fed through opening 39 passes between the outside of tube 38 and the inside of tube 29 and sleeve 39, around the outside of atomizing nozzle 35, and thence out of the projecting end of sleeve 30 into mixing chamber 22. When burning a relatively slow-burning, low hydrogen-content gas such as natural gas, the sleeve 30 may be pulled. back to the same position as for burning passing through the sleeve 40 into the front openings 25 or into the front and rear openings 25' and 261', depen ing on how far the sleeve 4d is extended. The front and rear openings 25 and 26' are preferably offset'axially enough to allow the sleeve flange 41 to be positioned entirely between them as a partition without overlapping any of the openings, and when the flange 41 is so positioned it directs all of the fuel through the inner row of Vopenings 2S' and all of the combustion air through the youter row of openings 26', so that there is no preinto the refractory depression, and mixes with the balance of the combustion air in the refractory depression 14. This has proved successful in practice when using coke oven gas in a high temperature furnace to heat steel billets to temperatures of at least 2350 F. Directing pure air (eg, combustion air only) through the rear row of radial openings 26', which are nearest the surface of the refractory depression 14', has the additional advantage of protecting the refractory material from excessively close exposure to the Vintense flame of coke oven gas or other highly combustible fuels.

When the burner shown in FIGURE 4 is to burn fuel oil or slow-burning gas, such as natural gas, the sleeve 40 is retracted until the flange 41 is baci: of the forward end of wall 17. The combustion air is then directed by the shoulder 18' into the stream of oil or gas issuing from within the sleeve 40, and all of the combustion air and fuel are well mixed as they pass through the mixing chamber enclosed by the surface 42 before entering the radial openings 25 and 26', and after leaving the openings 25 and 26 burn in the refractory depression 14 to produce the same heating effects as with faster burning fuels when the sleeve 4t) is in its advanced positions. The sleeve 4t) is shiftable to accommodate different fuels without turning off the burner flame.

Although the specific embodiments of my invention illustrated in FIGURES 1 and 4 are shown in combination oil-and-gas burner form, it readily will be appreciated by those skilled in the art to whom this invention is shown, that they become straight gas burners whenever the tube 38 (and 38') and associated parts of the oil atomizer are withdrawn by unscrewing member 37 after respectively disconnecting oil and atomizing

iiuid connections

34 and 36, the remaining opening at the rear end of extension 31a being closed in such case by a plug. Moreover, when my new burners are utilized as straight gas burners with a foreseeable sufficiency of a relatively fastburning fuel gas, the sleeves 30 or 40 might be made in one instead of two parts, inclusive of the

portions

29 and 29 respectively, and fixed in position if desired. In the case, for example, of my FIGURE 4 embodiment in straight gas burner form with the oil atomizer withdrawn, such a one-piece sleeve 30 might be fixed so as to extend to a position wholly separating the axially spaced rows of front and rear outlet openings 25' and 26', in which case all of the fuel gas would go through one set of those openings in one row and all of the combustion air would go through the other set of such openings in the other row for the formation of a mixture outside of such burner without departure from my invention as disclosed in my United States application Serial No. 308,215, filed September 6, 1952.

My further modification, illustrated in FIGURE 7, is shown mounted in a refractory furnace wall 50, which term wall may comprehend the sides, ends, iioor and/ or ceiling of a furnace depending upon where it may be desired to locate my new burners, a plurality of which are usually used together. Furnace 5@ has an opening 51 therein for the receipt, in a normal situation, of a refractory burner port block 52 which closes it when the port block is in place. The furnace side of the port block form a continuation of the interior surface 53 of the furnace and that side may be provided with a flaring or cup-shaped depression 54 with a cylindrical portion 55 and a flaring portion 56. The port block 52 may be of castable refractory cast on a backing plate 57 so that the port block may be bolted in position in a furnace. The port block 52 in turn is provided with a central axial opening 53, in the same manner as port block 1t), for the receipt of a fuel gas burner 59.

Burner 59 comprises an outer tubular metal shell 60 which tits and is held in opening 5S. The inner end of shell 60 terminates in a burner cap 61, the end 62 of which is closed to make the burner a non-forward firing burner in which the streams are directed generally along the interior surface of the furnace. Cap 61 is a part of the burner most exposed to prevailing furnace temperatures and preferably is made of a heat-resisting alloy metal. That exposure is usually less for the remaining parts of burner 59 which consequently may be made of a metal which is less heat-resistant and less expensive. It may also be that cap 61 may have to be replaced occasionally due to such exposure during operation of the burner and furnace.

To facilitate the employment of a separable replaceable cap 61, a parting surface 63 may be provided in manufacturing the burner between the outer edge of cap 61 and the inner edge of the remainder of shell 60 as shown in FIGURE 7. Cap 61 may be secured to shell 60 by a continuous weld bead 64 of metal, by peripheral overlapping, or by respectively internal and external interengaging threads on cap 61 and the adjoining edge of the remainder of shell 60. In this way, if and when a cap 61 is to be changed or replaced, burner 59 can be removed from the opening 58, or the entire port block 52 with the burner therein can be removed before the separation of burner and port block. After separation of the burner, the weld 64 may be burned off and the old cap 61 taken away whereupon a new cap 61 can be positioned in place and rewelded to the remainder of the shell 60 before lthe burner 59 is put back into operation in the furnace 50.

The outer or rear end of tubular shell 60 may be threaded to engage a cylindrical fiange 65 on a combustion air manifold 66, to the interior of which a pipe 67 supplies combustion air at the desired temperature (which may be ambient) and pressure for the intended operation of burner 59. The quantity of air entering manifold 66 from pipe 67 will normally be in proper proportion to the quantity of fuel gas fed to burner 59 for the combustion of that fuel gas at maximum burner capacity. Further, as will be understood by those skilled in the art to whom this invention is disclosed, a plurality of such new burners will be operated from a single control. system for all of the burners in a particular furnace or for a particular section of the burners in that furnace. In some cases, when quick cooling of a furnace is desired, the fuel gas H can be entirely shut olf and the combustion air to the burner may be left on to expedite the furnace cooling down period.

Burner 59 may be fastened in place relative to port block 52 by bolting it through arcuate liange 68 to plate 57, a gasket often being interposed between such manifold and plate 57 to seal off any slight space that may exist around burner 59 when it is fitted into opening 5S in port block 52. A rear cover plate 69 may be provided and bolted to the back of manifold 66 to close the back of burner 59 except for an opening 70 extending through manifold 66 in registry with an opening 71 in cover 69. Cover 69 may be also provided with a cylindrical flange 72 which partially fills an annular packing recess 73 in the back of manifold 66 to compress packing 74 therein against the outside of an inner tubular sleeve member 75.

In the further embodiment shown in FIGURE 7, the inner tubular member 75 extends coaxially through shell 60 and the innermost end 76 of member 7S engages the interior of cap 61 in a manner to separate the interior thereof into a first chamber 77 communicating with the interior of member 75 and a second chamber 78 communicating with the interior of shell 60 inclusive of cap 61 externally of member 75. Thereby, burner 59 will have two separate, independent passages entirely therethrough, one through the inside of inner tubular member 75 and the other through the interior of outer tubular member 69 in the annular space around member 75. In cases of a relatively fast-burning fuel gas, or otherwise, the respective streams of fuel and combustion air through the respective passages leading to the first and

second chambers

77 and 78 respectively will be kept separate until they mix around the outside of the sides of cap 61 as those streams are discharged from the cap generally in a direction along the interior furnace surface adjoining them, that surface being the flaring recess portion 56 in the illustrated embodiment.

The discharge of the stream moving toward the front of burner 59 around the outside of tubular member 75 takes place through the discharge outlets 80 extending around the periphery of cap 61. The axes of the outlets 80 are generally along adjoining surface of recess 56. The other stream passing to the front of burner 59 through the inside of tubular member 75 is discharge through the outlets 81 around the periphery of cap 61, the axes of the outlets 81 being somewhat convergent, if desired, rather than parallel relative to the axes of the outlets 80. In the illustrated embodiment of FIGURE 7, combustion air passes through manifold 66 into the passage between the inside of shell 60 and the outside of inner tubular member 75 and discharges through outlets 80, whereas diately adjacent the combustion source.

fuel gas passes through a valve 82 and an elbow 83 into the inside of inner tubular member 75. That fuel gas is discharged through the outlets 81 and mixes with the requisite combustion air outside cap 61 for the combustion of that fuel gas, in the same manner that occurs when my embodiment of FiGURE 4 is on gas cycle and sleeve 40 is positioned so as to separate the respective front and rear openings 25 and 26.

A continuous Weld bead 79 may be provided, where end '76 and the interior shoulder 61a in cap 61 adjoin, to lfasten member 75 to cap 61 in view of my replaceable provision for such a cap 61. Hence', in putting a burner 59 together, the rear end 84 of inner tubular member 75 may be passed through opening 70 before cap 61 is welded to the remainder of shell 60. Thereupon, packing 74 can be put in place and cover 69 attached. The threads at the rear end 84 of member 7S may then be engaged by the front tapped opening in elbow S3, either before or after valve 82 is attached thereto as shown, there being a iianged coupling (not shown) on the other side of valve 82 for connection and disconnection purposes relative to piping supplying fuel gas to valve 82 and to the interior of elbow 83 when valve 82 is opened for the operation of burner 59 on gas. VA threaded and tapped rear opening 85 is provided at the back of elbow 83 in alignrnent with the axis of inner tubular member 75, opening $5 being normally closed by a plug 86.

If it should be desired to place the burner of FIGURE 7 on oil cycle, the gas valve 82 may be shut off and the plug 86 removed so that an oil atomizer nozzle, suitably externally threaded, may be engaged by the threads of the opening 85 in which case atomized oil will be discharged into the interior of elbow 83 and pass through the leaving the burner through outlets 8,1. For purposes hereof, such atomized oil may be termed a fuel in gaseous form. Normally if a burner is on one fuel, the other fuel is not utilized, such particularly being the case Where oil is used as a standby fuel in seasons and at times when fuelgas may not be available. When burner 59 is going to be on gas cycle for a foreseeable period, then the oil atomizer normally would be withdrawn and the burner used as shown in FIGURE 7.

The burner shown in FIGURE 8 corresponds substantially in structure and functioning to the modification shown in FIGURE 7 and corresponding parts in FIG- URE 8 are given the same reference numerals with the addition of a prime factor thereto. However, as shown in FIGURE 8, the recess 5ft in port block 52 is wholly cylindrical and has a fiat surface 8'7' adjoining cap 61'. The axes of the outlets S0 lie in a plane parallel to the plane of surface S7 whereas the axes of the outlets 81 define a surface convergent upon theplane of the axes of outlets 80 as one moves farther away from the axle of burner 59'. The Wall 88 at the end of the recess 5d will assist in providing forward velocity to the streams leaving the

respective outlets

80 and 81 for combustion in the operation of burner 59.

A still further burner modification is shown in FIG- URE 9 which generally corresponds in structure and functioning to the burner shown in FiGURE 7 and such FiG- URE 9 burner is provided with corresponding reference numerals with the addition of a double prime factor thereto. Howeven'in the FIGURE 9 modification mounting, port block 52" has no recess. Instead, the face 39 of port block 52" is convex and annularly continuous around the opening 58" which is filled by the burner 59". Thereby, provision is made for diffusion of radiant energy imme- And, burner cap 62 has a machine finish cylindrical surface 90 in its shouldered portion 91 for engagement by a machine finish surface 92 on member 75 to form a substantially tight joint at the end 76" of that inner tubular member 75". The rear end of inner tube member '75" may be threaded and rmly held by the rear plate 93 which has a rearward extension 94:- and a tapped central opening at the back thereof which is closed by a plug 95. The length of threading at the rear of member 75 and the co-engaging threading in plate 93 is long enough to provideV for any desired axial adjustment of member 75 relative to shell 60" and thereby of cap 61, even to the extent, if desired, of providing some separation between the front end 76 of member 7.5 and shoulder 91 for limited intermingling of the respective streams through burner 59 prior to discharge thereof through the outlets. Plate 93 and extension 9d are structurally and functionally similar to plate 31 and extension 31a (FIGURE l) respectively, while plug 95 fills the opening corresponding to the opening in the rear of extension 31a through which, in the FIG- URE 1 embodiment, an oil atomizer is inserted and held for use if and when the burner is to be put on oil cycle.

In the FIGURE 9 modification as shown, the oil atomizer has been removed and the burner 59 is prepared only for operation on fuel gas admitted through a pipe 96 into the interior of extension 94 and thereby into the interior of inner tubular member 7S". With member 75 positioned as illustrated and held by a loclrnut 93a, the fuel gas stream through member 75 and the combustion air stream through the annular space in shell 60 around member 75 are kept separate until admixture thereof outside of cap 62'. following the discharge of such streams respectively through the outlets 81" and 80". In some cases, it may be desirable to reduce the temperature gradient and rate of heat transference through the end of a burner cap like end 62". In the FIGURE 9 embodiment, short lengths 97 of high heat-resistant alloy rod may be welded to the front side of end 62 and a castable refractory tip 98 cast in place over the studs 97 before the burner is inserted into the port block and furnace where it is to operate.

In my modied burner 100 shown in FIGURE 10, a shell 101 is provided as an outer tubular member which is uniformly cylindrical substantially throughout the length thereof passing through a straight central opening 102 in a burner port block 103 having a aring recess 104 therein on the furnace interior surface side thereof. Outer tubular member `101 includes a burner cap 105 at its inner end, the cap 105 being secured at the parting surface 106 to the remainder of member 101 as by welding 107 as described in connection with cap 61 in the FIGURE 7 embodiment. The front or furnace end 108 of member 101 and cap 105 is closed as shown. A shoulder in the form of an internally extending annular flange 109 is provided in cap 10S (as by undercutting) and has a machine finish cylindrical surface 110 for engagement by the outside machine finish surface 111 at the inner end of an inner tubular member 112. Flange 109 is positioned between the inner row or set of discharge openings 113 and the outer row or set of discharge openings 114, such discharge openings preferably being provided around the whole periphery of tubular cap 105. Preferably, too, the axes of discharge outlets 114, which outlets may be radial or offset from radial position toward tangential position, lie in a surface of revolution which is generally parallel to the flaring face of recess 104 immediately ad- .joining burner 100. The discharge outlet set 113 may have the axes thereof somewhat convergent, or parallel, relative to such surface of revolution containing the axes of outlets 114. Y

The shell of burner 100 may be provided with an annular flange 115 for attachment by bolts 117 to the port block backing plate 116. Annular shims 118 may be used betweeniiange 115 and plate 116 for any axial adjustment of burner 100 relative to opening 102. Thereby,

l Q the axial spacing of cap 105 relative Ito recess 104 is made adjustable should it be desired to have the streams issuing from the

outlets

113 and 114 moved `somewhat closer to r farther away from the back of recess 104, direct impingement of a fuel stream on such flaring portion preferably being avoided.

As shown, burner 100 is illustrated as a straight fuel gas burner, rather than a combination oil-and-gas burner or a straight oil burner. The inner tubular member 112 extends rearwardly, that is outwardly, in the burner and passes through an opening 119 in a rear extension 120 of shell 101, the rear end 121 of member 112 being threaded to engage threads in a boss 122 on a cover plate 123. Cover plate 123 may be provided with a cylindrical flange 124 to cooperate with packing recess 125 on the rear side of opening 119 whereby packing 126 may be pressed around member 112 when in place in the manner of a packing gland to seal that end of the burner.

Combustion air may be admitted directly to the interior of member 112 through a pipe 127 which is also secured to the boss 122 as shown in chain-like outline. Member 112 is readily positioned because the contact between the surface 111 at the inner end thereof and surface 110 is a sliding fit which is preferably precise enough to form a joint which keeps separate the respective streams discharging through the axially spaced sets of

outlets

113 and 114. Spacers may also be placed between the front side of plate 123 and the rear of extension 120 to enable an adjustment to be made in the position of member 112 relative to the burner shell body 101, in the event, for example, that the amount of overlap in the joint between the surfaces 110 and 111 is to be changed.

Fuel gas may be admitted through a pipe 128 to the interior of shell 101 and cap 102, externally of tube 112. Normally the volume of combustion air is greater than the volume of fuel gas used whether the burners in question are operating at maximum capacity or at a turndown level of operation. Hence, the FIGURE embodiment provides for greater cooling to the inside of exposed end 108 whether the air admitted through pipe 127 is at ambient temperature or preheated, than would be provided if the fuel gas stream passed through the interior of member 112. Such combustion air is separately discharged through the outlets 113 whereas the fuel gas is discharged separately through the outlets 114, a combustible mixture taking place outside of the interior of the burner 100.

In some cases, it may be desirable to provide a pilot for lighting purposes with each burner. Thus, if applied to the burner shown in FIGURE l0, port block 103 and backing plate 116 may have a pilot light opening 129 extending therethrough. The discharge end of a conventional pilot burner 130 may be positioned so as to discharge into opening 129 in the manner shown, such discharge generally comprising a relatively small quantity of a combustible mixture of fuel gas and air so that when the pilot 130 is lighted, a thin flame 131 is produced which shows on the furnace side of port block 103 adjacent burner cap 105. Hence, whenever burner 100 is turned on, the flame 131 will light the fuel and air discharged by the burner 100.V

While I have illustrated and described present preferred embodiments of the invention and methods of practicing the same, it will be recognized that the invention may be otherwise variously embodied and practiced within the scope of the following claims.

I claim:

l. A high thermal release furnace burner, comprising in combination, a body adapted to project at one end into a furnace, said body having a chamber in its projecting end with a plurality of discharge outlets to the outside of said burner extending radially from the chamber, a movable cylindrical sleeve extending into the chamber with the end of the sleeve in the chamber belled outwardly to a position adjacent the inner ends of said outlets, means to move said sleeve in said chamber relative to said inner ends of said outlets, and respective means to conduct a stream of fuel and a stream of combustion air in the direction of said sleeve, one along the inside and the other along the outside of the sleeve, toward said outlets, said body and outlets having sufficient cross sectional area to pass the whole fuel and combustion air requirements of said burner, whereby the proportion of air and fuel passing through said outlets is variably controllable by the position of the belled end of the sleeve relative to the inner ends of said outlets.

2. A high thermal release furnace burner, comprising in combination, a body adapted to project at one end into a furnace, said body having a `chamber in its projecting end with a plurality of axially spaced rows of discharge outlets to the outside of said burner extending radially from the chamber and having their inner ends separated by a wall portion of said chamber, and a. tubular sleeve extending into said chamber and having a front end in juxtaposition to said wall portion and the inner ends of said outlets, means to position said sleeve longitudinally and means to supply fuel and combustion air along the sleeve, one along the inside and the other along the outside of the sleeve, toward said outlets, said body and outlets having suihcient cross sectional area to pass the whole fuel and combustion air requirements of said burner,

whereby said air and fuel and entirely separated until after discharge from said outlets when the front end of said sleeve is positioned between said rows.

3. A high thermal release furnace burner, comprising in combination, a tubular body adapted to project at one end into a furnace, said body having a cap at its projecting end and a plurality of outlets to the outside of said burner extending laterally through said projecting end of the body adjacent the cap, a peripherally continuous portion of the inner surface of said body separating the in- `ner ends of certain of said outlets from the inner ends of others of said outlets, respective means to conduct a stream of fuel and a stream of air for substantially complete combustion of said fuel separately through said body toward said cap, and means to keep the respective streams separated before reaching the inner ends of said outlets comprising a tubular sleeve extending through the body with its end adjacent the cap positioned close to said surface portion and inner ends of said outlets to connect at least said certain inner ends to the space in said body outside of the sleeve and others of said inner ends to the space inside the sleeve, one of said streams being directed through the inside of the sleeve and the other outside of the sleeve, said body and outlets having sufficient cross sectional area to pass the whole fuel and combustion air requirements of said burner.

4. A high thermal release furnace burner, comprising in combination, a body adapted to project at one end into a furnace, said end of the body being formed as a burner nozzle with a cap on its projecting end, a chamber in the nozzle extending to the cap, a plurality of substantially radially extending burner outlets from the chamber adjacent the cap, a sleeve movably mounted within the body to shift one end of the sleeve close to and away from the cap, said sleeve having a portion movable into relatively close proximity to the. inner ends of said outlets, conduits connected to said body for supplying fuel and air, one along the inside and the other along the outside of said sleeve, toward the radial outlets, said conduits being adapated to supply both gaseous and liquid fuels, and means operable to shift said portion of `said sleeve rearwardly of` said radial outlets to change the distance between said sleeve and said radial outlets and thus adjust the place Within said body where the fuel and air are initially brought together, whereby the burner is capable of using fuels of Widely differing combustion characteristics.

5. A high thermal release furnace burner, comprising in combination, a tubular body adapted to project at one end into a furnace, said end of the body being formed as a generally cylindrical burner nozzle with a cap: on 1ts projecting end, a chamber in the body extending into the nozzle up to the cap, the chamber having a relatively small diameter cylindrical portion in the nozzle and a larger diameter portion to the rear of the nozzle, a plurality of substantially radially extending burner outlets from the chamber through the nozzle adjacent the cap, a sleeve movably mounted within the body with a projecting forward end of less diameter than the smaller portion of the chamber and movable through the larger and smaller portions of the chamber close to and remote from the cap to adjust the distance between said forward end of said sleeve and said burner outlets, an oil atomizer mounted inside the sleeve in the larger portion of the chamber, means to supply gaseous fuel through the sleeve past said oil atomizer, and means to supply combustion air around the outside of the sleeve into the chamber, whereby `the projectingend of the sleeve may be drawn back adjacent the atomizer when oil or relatively slowburning gas is burned and may be advanced adjacent the inner ends of the burner outlets when a relatively fastburning fuel is burned.

6. A high thermal release furnace burner, comprising in combination, atubular body adapted to project at one end into a furnace, said end of the body being formed as a burner nozzle with a cap on its projecting end, a chamber in the body extending into the nozzle up to the cap, the chamber having arelatively small diameter cylindrical portion in the nozzle and a larger' diameter portion to the rear of the nozzle, the two portions being separated by a connecting conical shoulder sloping inwardly toward the projecting end of the body, a plurality of rows Vof substantially radial outlets from the chamber through the nozzle adjacent the cap, a sleeve movably mounted within the body with a projecting forward end of less diameter than the smaller portion of the chamber and shiftable through the larger and smaller portions of the chamber close to and remote from the cap, the said end of the sleeve being belled outwardly to slide against the smaller portion of the chamber across the inner ends of the radial openings, an oil atomizer mounted inside the sleeve in the larger portion of the chamber, means to supply gaseous fuel through' the sleeve past said oil atomizer, and means to supply combustion air around the outside of the Vsleeve into the chamber, whereby the projecting end of the sleeve may be drawn back adjacent the atomizer when oil or relatively slow-burning gas is burned and complete premixing is desired, and may be advanced across the inner ends of a forward row of radial outlets when a faster burning fuel is burned and little premixing is desired, and may be positioned between the inner ends of different rows of said outlets when a very fast-burning fuel is burned and no premixing is desired.

7. A burner for a furnace having awall and a burner opening therethrough, comprising, in combination, a body adapted to close an opening in a wall of said furnace, saidbody having a front end adapted to be adjacent the inside of said wall of said furnace, said body being tubular and having said front end substantially closed, a plurality of rows of axially spaced outlets into said furnace extending generally radially through said front end between the inside and outside of said body, a positionable inner tubular member extending within said bodytoward said front end a distance sufficient to substantially separate said rows of said outlets, respective means for passingcombustion air and fluid fuel through Vsaid body in separated relation on opposite `sides of said member for selective discharge through said rows of said outlets,` said body and outlets having sufficient cross sectional area to pass the whole fuel and combustion air requirements of said burner, and means to hold said member so positioned in said body.

8. A burner for a furnace having a wall and burner opening therethrough, comprising, in combination, an axially extending tubular body adapted to pass through said opening in said wall to the inside of said furnace, said body having a size and configuration adapted to provide a generally close fitting relation to said opening to close it and having a substantially enclosed front end, a plurality of axially spaced outlets extending through said front end at an angle to the axis of said body to discharge into said furnace, an inner tubular member extending axially within said body to a position adjacent the inner ends of said outlets to substantially separate respective ones of said outlets, respective means for passing combustion air and fuel in gaseous form and separated relation through said body on opposite sides of said member, said body and outlets having sufficient cross sectional area to pass the whole fuel and combustion air requirements of said burner, and means to hold said member in selected position in said body with the inner endV of said tubular member generally separating said respective axially spaced outlets.

9. A burner for a furnace having a wall and a burner block in said wall with a burner opening therethrough, comprising, in combination, an axially extending tubular shell body adapted'to pass through said opening in said wall to the inside of said furnace, said body having a size and configuration adapted to provide a generally close fitting relation to said opening and having a substantially enclosed burner cap front end, a plurality of generally radially extending discharge outlets through the side of said front end to discharge into said furnace adjacent said wall, an inner tubular member positioned in generally concentric relation yto the axis of said body and extending axially within said body to a forward position adjacent and between respective inner ends of respective ones of said outlets, means for passing a gaseous fuel through the interior of said body on one side of said member, means for passing combustion air for combustion of said fuel through the interior of said body on the other side of said member, said body and outlets having sufficient cross sectional area to pass the whole fuel and combustion air requirements of said burner, and means in said burner to hold said member in said position.

l0. In a burner for an industrial furnace or the like, in combination, a tubular body having an inner end adapted tofproject through a wall of said furnace into the interior thereof with the furnace end of said burner adjacent to said wall, said projecting end being closed and having two sets of outlets for discharge to the outside of said burner generally in the direction of the adjoining surface of said wall, a tubular member within said body extending substantially to said projecting end to form two passages therewith adjacent the inner ends of said sets of outlets respectively, one of said passages extending through said tubular member and one of said sets of said outlets, said tubular member being spaced laterally inwardly from the inside of the sides of said projecting end to define a second passage around the outside of said tubular member extending through said tubular body and `another set of said outlets, said body and sets of outlets having sufficient cross sectional area to pass the whole fuel and combustion air requirements of rsaid burner, whereby when a stream of fuel in gaseous form is admitted to one of said passages and a stream of combustion air is admitted to the other of said passages, said gaseous streams will be respectfully discharged through said sets of outlets substantially to come together substantially immediately outside of said projecting end of said burner in combustible mixture proportions.

Vll. In a burner for an industrial furnace or the like, in combination, an outer tubular member having a burner cap of the same diameter at the furnace end of said burner projecting inwardly of the interior surface of said furnace, said burner cap` being closed at the front end thereof, a plurality of sets of axially spaced outwardly extending outlets through the periphery of said burner cap` to the outside of said burner, an internal shoulder in, said cap between the respective inner ends of said respective sets of Outlets, an inner tubular member extending coaxially through said outer tubular member and having its front end in engagement with said shoulder to form a passage through the inside of said inner tubular member and the axially foremost set of said outlets and a further passage between the inside of said outer tubular member and the outside of the inner tubular member extending through said axially rearmost set of said outlets, said body and sets of outlets having sufiicient cross sectional area to pass the whole fuel and combustion air requirements of said burner, means for passing a fuel in substantially gaseous form through one of -said passages, and means for passing combustion air through the other of said passages.

12. In a gas burner for an industrial furnace or the like, in combination, a refractory port block adapted to form a part of an interior surface of a furnace, said port block having a central opening therethrough, a tubular burner shell fitting into and closing said opening, a nozzle burner cap closing the inner end of said shell and projecting into said opening, said burner cap having a plurality of generally laterally directed discharge outlets to the outside of said burner around the periphery thereof adjacent said surface, certain of said outlets being axially displaced from others of said outlets, a gas tube extending coaxially through said shell into said burner capi, the inner end of said tube extending substantially into engagement with the interior of said burner cap` adjacent the inner ends of the axially innermost ones of said outlets, the innermost ones of said outlets being in communication with the space inside said tube, the outermost ones of said outlets being in communication with the space in said burner outside said tube, means for passing a fuel gas through said burner on one side of said tube and combustion air through said burner on the other side of said tube, said shell, tube and outlets having sufficient cross sectional area to pass the whole fuel and combustion air requirements of said burner, whereby said gas and air are segregated until the discharge thereof from said displaced outlets repsectively.

13. In a burner for an industrial furnace or the like having an opening through the wall thereof to be substantially filled by such a burner, in combination, a tubular body terminating in a burner tip projecting inwardly of the adjoining interior surface of said furnace, said burner tip being closed across the furnace end thereof and having a multiplicity of outlets from the interior of said tip directed generally outwardly from the axis of said burner and substantially along said adjoining interior surface around the axis `of said burner, said outlets being to the outside of said burner and adapted to be adjacent said adjoining interior surface when said burner is in place in said furnace, certain ones of said outlets in said tip being in front of other ones of said outlets, an inner tubular sleeve member positioned coaxially in said body, said member being spaced from the inside of said body, said member having its front edge periphery adjoining the interior of said tip to partition the interior of said tip into a central space communicating with the inner ends of said certain ones of said outlets and an annular space communicating with said other ones of said outlets, means for holding said member in position in said body, means for admitting combustion air to one of said spaces along one side of said member for discharge through the outlets communicating with said one of said spaces, and means for admitting a fuel in gaseous form to the other of said spaces along the other side of said member for discharge through the outlets communicating with said other of said spaces, whereby the respective streams from the respective outlets in communication with the respective spaces mix in said furnace upon discharge from said burner.

14. A burner for an industrial furnace or the like having a refractory wall with a burner opening therethrough, comprising, in combination, a burner body adapted to fit into said opening and thereby close it, an axial nozzle at the inner end of said body having a cross-sectional area smaller than the cross-sectional area of said body outwardly of said nozzle, said nozzle projecting into said furnace or the like, said nozzle having a plurality of rows of discharge outlets to the outside of said burner extending generally laterally through said nozzle around the axis thereof and in the direction `of the adjoining inner surface of said wall, said body having respective passages theretbrough for separated flow of uid fuel and combustion air therethrough, an annular member in said nozzle between respective adjoining rows of said discharge outlets to generally separate said rows, one side of said member being in communication with one of said respective passages and the other side being in communication with another of said respective passages, and means to selectively position said member axially for mixing of fuel and air inside or outside of said nozzle.

References Cited in the le of this patent UNITED STATES PATENTS 1,122,740 Gwynn Dec. 29, 1914 1,165,835 Birkholz Dec. 28, 1915 1,337,328 Said Apr. 20, 1920 1,686,833 Moore Oct. 9, 1928 1,702,298 Hetsch Feb. 19, 1929 2,368,178 Turpin Jan. 30, 1945 2,375,625 Conway May 8, 1945 2,385,153 Morton Sept. 18, 1945 2,458,541 Urquhart Jan. 11, 1949 2,465,155 Higley Mar. 22, 1949 2,561,795 Hess July 24, 1951 2,613,737 Schwietert Oct. 14, 1952 2,631,656 Siemon Mar. 17, 1953 2,672,402 Stokes Mar. 16, 1954 FOREIGN PATENTS 265,041 Great Britain Feb. 3, 1927 UNITED STATES PATENT oEEICE CERTIFICATE 0E CORRECTION Patent Noo 3 139q 138 June 3()S1 1964 Frederick 5 Bloom It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as Corrected belowa Column 3, line 57n strike out ""in"; Column 5 line 44hz for "form" read mforms Column 12 line ll7 for "flange" read m flange line 8 for discharge read M discharged column 71T line 6C)Q for "axle" read axis wg Column 9I line 2lY for @'ohandke" Tead chain-line g Column lOE line 27, or "and' second occurrence, Feed are column I3Y line 40q for "'Tepseotvelyr head respectively Signed and sealed this 10th day of November 1964.,

Attest:

ERNEST Wc, SWIDER EDWARD J. BRENNER nesng @fioer Commissioner of Patents

Claims

1. A HIGH THERMAL RELEASE FURNACE BURNER, COMPRISING IN COMBINATION, A BODY ADAPTED TO PROJECT AT ONE END INTO A FURNACE, SAID BODY HAVING A CHAMBER IN ITS PROJECTING END WITH A PLURALITY OF DISCHARGE OUTLETS TO THE OUTSIDE OF SAID BURNER EXTENDING RADIALLY FROM THE CHAMBER, A MOVABLE CYLINDRICAL SLEEVE EXTENDING INTO THE CHAMBER WITH THE END OF THE SLEEVE IN THE CHAMBER BELLED OUTWARDLY TO A POSITION ADJACENT THE INNER ENDS OF SAID OUTLETS, MEANS TO MOVE SAID SLEEVE IN SAID CHAMBER RELATIVE TO SAID INNER ENDS OF SAID OUTLETS, AND RESPECTIVE MEANS TO CONDUCT A STREAM OF FUEL AND A STREAM OF COMBUSTION AIR IN THE DIRECTION OF SAID SLEEVE, ONE ALONG THE INSIDE AND THE OTHER ALONG THE OUTSIDE OF THE SLEEVE, TOWARD SAID OUTLETS, SAID BODY AND OUTLETS HAVING SUFFICIENT CROSS SECTIONAL AREA TO PASS THE WHOLE FUEL AND COMBUSTION AIR REQUIREMENTS OF SAID BURNER, WHEREBY THE PROPORTION OF AIR AND FUEL PASSING THROUGH SAID OUTLETS IS VARIABLY CONTROLLABLE BY THE POSITION OF THE BELLED END OF THE SLEEVE RELATIVE TO THE INNER ENDS OF SAID OUTLETS.