US2932349A - Flame retention gas burner nozzles - Google Patents

Description

Aprl 12, 1960 w. FERGUSON 2, 2,

FLAME RETENTION GAS BURNER NOZZLES Filed Jan. 25, 1957 VENTOR %2294272 F'erywn ATTORNEY z,932,349 i FLAME RETENTION GAS BURNER NOZZLES William Ferguson, Philadelphia, Pa., assignor to National Airoil Bumer Company, Incorporated, Philadelphia, Pa., a corporation of Delaware Application January 25, 1957, Serial No; 636,'346 6 Claims. (c. 158-116 This invention relates to gas burner nozzles and more particularly to such nozzles which will retain the flame without flash back.

Nozzles have heretofore been proposed which are suitable for burning natural gas, the principal constituent of which is methane, as well as butane, propane and other combustible gases. These nozzles have not, however, been suitable, because of the tendency for the flame to flash back into the inspirator, for burning gas which contains large quantities of free hydrogen.

It is the principal object of the present invention to provide a nozzle whichis particularly suted for the burning of gas containing large quantities of free hydrogen.

It is a further object of the present invention to provide a nozzle of the character aforesaid which is relatively 'simple in Construction but which will have a long life.

It is a further object of the present invention to provide a nozzle having a separate main port which is retained in a relatively cool condition, and which can be readily changed, renewed or altered as desired.

It is a further object of the present invention to provide a nozzle having a separate main port and a plurality of supplemental ports with the areas thereof in predetermined interreIatiOn. i

It is a further object of the present invention to pro vide a nozzle having provisions for increased flame surface.

It is a further object of the present invention to provide a nozzle of the character aforesaid having auxiliary provisions for introducing additional fuel for starting up with a cold furnace or the like.

Other objects and advantageous features of the invention will be apparent from the description and claims.

The nature and characteristic features of the invention will be more readily understood from the following description, taken in connection with the accompanying drawings forming part thereof, in which:

Figure 1 s a view partly in elevation and partly in section showing the mounting, in a fumace wall, of the bumer nozzle in accordance with the present invention;

Fig. 2 is an end elevational view, enlarged, of the nozzle shown in Fig. 1, and as seen from the discharge side thereof; and

Fig. 3 is a longtudinal sectional view taken approximately on line 3-3 of Fig. 2.

It should, of course, be understood that the description and drawings herein are illustrative merely, and that various modifications and changes can be made in the structure disclosed without departing from the spirit of the invention.

Like numerals refer to like parts throughout the several vews.

Referring now more particularly to the drawings, the burner nozzle of the present invention, shown generally at 10, is preferably connected to an inspirator 11 of well known type which includes a venturi tube 12 through which from about ,80 to 100% of the theoretical total air required for combustion isinspirated by the pressure of the incoming combustible gas. The combustible gas supplied through a fuel pipe 13, controlled -by a gas 24 and with a rear end wall' 26 into which a connecter pipe 27 from the venturi tube 12 is threaded and has a flat front end wall 28 with a central threaded opening 29 for the reception of an insert 30 to be described.

The wall 28 is provided with a plurality of ports 31, eight being shown, preferably of predetermined area as hereinafter described and the wall thickness of the metal of the front wall 28 is preferably such that the length of these ports 31 is approximately of the diameter of each of the ports 31. The longtudinal axes of the ports 31 can be parallel to the longtudinal axis ofthe opening 29 although for some purposes these aXes are inclined outwardly with a cone angle up to about 40, so as to provide a divergent delivery through the ports 31.

If desired, although itis not essential, a plurality of igniter ports or pilot holes 32 can also be provided in the front wall 28 for stabilzing ignition to the main stream of gas and air, the quantity of fluid passing therethrough being of the order of one percent of the total gas-air stream.

The insert 30 preferably consists of a front portion33 on which the threads 34 are provided for engagement in the threaded opening 29 in the wall 28 and with a central opening 35 longitudinally axally aligned with the body portion 25 of the nozzle 10 and a rear frustoconical or flaring portion 36 with a rear rim portion 37 in spaced relation to the interier of the wall of the body portion 25 to provide an annular space 38 for gas delivery to the ports 31. The respective areas of the ports 31 and the port 35 are preferably such that the port 35 represents about 50% of the total area for gas-air delivery and the remaining 50% of the area for gas-air delivery is divided among the ports 31. The ports 31 also provide collective circumferences of at least twice that of a single area of the same magnitude and thus provide an increase in flame surface so that a shorter and hotter flame will be obtained for the same gas rate and mixture Volume.

It is intended that the gas supplied to the burner nozzle 10 through the pipe 13 will be rich in hydrogen and can be a by-product gas from gasoline refining Operations in petroleum refineries and containing about to percent hydrogen. This gas has a maximum rate of flame propagation when it is mixed with about 50 to 60 percent primary air, and the ignition velocity is in excess of 9 feet per second, but the ignition velocity will be reduced by increasing the amount of air delivered with' the combustible gas to about 80 to 100 percent of that theoretically required for combustion.

With the relatively long ports and with the distribution of port areas between the main port 35 and the Supplemental ports 31, and with the main port 35 having the extension 36 thereof irnmersed in and surrounded by advancing relatively cool gas and air, flash back is virtually eliminated and satisfactory burning eifected.

If desired, an auxiliary fluid connection 40 can be provided, between the valve 14 and the nozzle 10, and having a shut-off valve 41 therein and a restriction 42 for the delivery of additional raw gas through a fluid connection 43 in the body portion 25. With this con- Patented Apr. -12, 1960 necton the uel rate can be increased by 'an amount up to 50% for short periods. It will be noted that 'the connection is downstream of the valve 14 so that operation cannot be effected on raw gas without the main burner also being in operation. A 'safe arrangernent is thus provided."

I claim:

1. A burner nozzle for burning combustible gas-air mixtures comprising a hollow cylindrical body portion adapted to be connected to a source of combustible gasair mixture and having a front wall and a rear end spaced therefrom, said front'wall having a central opening and aplurality of additional opening therearound, said front wall at said central opening having a hollow flow dividing member extend ig intriorly therefrom within said body portion and rearwardly outwardly flared in spaced relation to said body portion, said flow dividing member having a central longitudinal axally disposeddischarge opening with an area c orresponding to about one half of the total gas-air mixture discharge area, the collective area of the additional openings c'orresponding to about one `half of the total gas-air mixture discharge area, said hollow member being open at its inner end, and the inner end thereof terminating intermediate said front wall and said rear end, said hollow member dividing the flow to, said central discharge opening and said plurality of openings with the space therearound in unrestricted communication with said plurality of openings and the space therein in communication with said central discharge opening.

2. A burner nozzle as defined in claim 1 in which the lengths of said additional openings are approximately three quarters of the diameters of said openings.

3. A burner nozzle as defined in claim 1 in which the longitudinal axes of said additional openings are in the range from about to 20 with respect to 'an upstream extension of the longitudinal axis of said discharge opening.

4. A burner nozzle for burning combustible gas-air mixtures comprising a hollow cylindrical body portion adapted to be connected to a source of combustible gasair rnixture and having a front wall and a rear end spaced therefrom, said front wall having a central opening and a plurality of additional openings therearound, an inserted flow dividing member in said body portion in engagement with and carried`by said front wall at said central opening, said flow dividing member having a central longitudinally'axially disposed discharge opening with an area corresponding to about one half of the total gas-air mixture discharge area, the collective area of said additional openings corresponding to about one half of the total gas-air mixture discharge area, said inserted member having a hollow frusto-conical wall extending interiorly from the front wall and within said body portion and terminating forwardly of said rear end of said body portion, the rearmost part of said frusto-conical wall being of largest diameter and in spaced relation to the interier of said body portion and dividing the flow to said central discharge opening and said plurality of openings with the space around said inserted member in unrestricted communication with said plurality of openings and the space within said inserted member being in communication with said central discharge opening.

5. A burner nozzle as defined in claim 4 in which the lengths of said additional openings are approximately three quarters of the diameters of said openings.

6. A burner nozzle as defined in claim 4 in which the longitudinal axes of said additional openings are in the range from about O to' 20 with respect to an Upstream extension of the longitudinal axis of said discharge openng.

References Cited in the file of this patent UNITED STATES PATENTS %2,472 Schneider June 28, 1910 1,096,943 Peake May 19, 1914 1,514,595 Ossel Nov. 11, 1924 1,938,852 McKee Dec. 12, 1933 1,948,737 Stettner Feb. 27, 1934 2,134,169 Wright Oct. 25, 1938 2,365',945 Ferguson Dec. 26, 1944 2,513,523 Schafer July 4, 1950 2,675,068 Gollus et al. Apr. 13, 1954

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