Oil burner nozzle

Abstract

A burner assembly for a furnace includes: a burner block having a flame cavity with a flame cavity length, and an oil nozzle insert having a tip that extends into the flame cavity by a distance of greater than one tenth of the flame cavity length.

Description

This application claims the benefit of U.S. Provisional Patent Application No. 60/620,460, filed Oct. 19, 2004.

FIELD OF THE INVENTION

The present invention relates to glass melting furnaces, and more particularly to improved burners for glass melting furnaces.

BACKGROUND OF THE INVENTION

Furnaces used in heating thermal loads, such as glass and metal melts, typically incorporate one or more burners set within burner blocks along the sides of the furnace. The burner produces the required heat by burning a liquid fuel, such as fuel oil or a gaseous fuel such as natural gas in an oxidant such as oxygen or oxygen-enriched air. The resultant flame extends over the melt, and heat is transferred from the flame to the melt by radiation and conduction.

FIG. 1 shows a prior art burner 10 of the type employed in glass melting furnaces. Burner 10 includes a block and frame assembly 12, a combustion oxygen inlet 16, an insert nut 18, a thermocouple 20, an atomizing oxygen inlet 22, a fuel check valve 24, a fuel oil inlet 26, an oil nozzle insert 28, an oil nozzle insert enclosure 30 and O-rings 14. Oil enters through the fuel oil inlet 26, and then is atomized and combines with combustion oxygen as it exits the burner block through the oil nozzle insert 28. As shown in FIG. 1, the tip 32 of the oil insert enclosure 30 terminates proximate to the rear of the frame assembly 12. The location of this tip 32 and the resultant location of the flame emanating from the tip often allows for an undesirable amount of heat exchange in the exterior wall of the furnace. This can cause damage to both the burner block and frame assembly 12 and also the thick stones in the exterior walls of the furnace.

An improved burner, which reduces heat damage to the burner and furnace is desired.

SUMMARY OF THE INVENTION

In some embodiments, a burner assembly for a furnace includes: a burner block having a flame cavity with a flame cavity length, and an oil nozzle insert having a tip that extends into the flame cavity by a distance of greater than one tenth of the flame cavity length.

In some embodiments, a burner assembly for a furnace includes: a burner block having a front face and a flame cavity with a flame cavity length, and an oil nozzle insert having a tip that terminates less than 90% of the flame cavity length from the front face of the burner block.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings illustrate preferred embodiments of the invention, as well as other information pertinent to the disclosure, in which:

FIG. 1 is a side cross-sectional view of a prior art burner assembly; and

FIG. 2 is a side cross-sectional view of an exemplary burner assembly of the present invention.

DETAILED DESCRIPTION

U.S. Provisional Patent Application No. 60/620,460, filed Oct. 19, 2004, is incorporated by reference herein as though set forth in its entirety below.

This description of the exemplary embodiments is intended to be read in connection with the accompanying drawings, which are to be considered part of the entire written description. In the description, relative terms such as “lower,” “upper,” “horizontal,” “vertical,”, “above,” “below,” “up,” “down,” “top” and “bottom” as well as derivative thereof (e.g., “horizontally,” “downwardly,” “upwardly,” etc.) should be construed to refer to the orientation as then described or as shown in the drawing under discussion. These relative terms are for convenience of description and do not require that the apparatus be constructed or operated in a particular orientation. Terms concerning attachments, coupling and the like, such as “connected” and “interconnected,” refer to a relationship wherein structures are secured or attached to one another either directly or indirectly through intervening structures, as well as both movable or rigid attachments or relationships, unless expressly described otherwise.

Referring to FIG. 2, an exemplary burner 100 for a glass melting furnace includes a burner block 102, a frame assembly 104, an oil nozzle insert 106, an oil nozzle insert enclosure 108, a combustion oxygen inlet 110, an atomizing oxygen inlet 112, a fuel oil inlet 114, a thermocouple 116, O-rings 118, and an insert nut 120. The burner block 102 includes a front face 122, back end 124, and a flame cavity 125.

The oil nozzle insert 106 includes a forward portion 126 and a rear portion 128. The forward portion 126 includes a nozzle tip 130 that extends into the cavity 125. In some embodiments, the forward portion 126 is preferably greater than 5 inches in length, or greater than one half of the cavity length. More preferably, the forward portion 126 is approximately nine inches in length L for a nozzle having a flame cavity of 10″ length, or approximately nine tenths of the cavity length.

The length of forward portion 126 is based on the size of the burner cavity 125. In some embodiments, the length of forward portion 126 is selected to be about 2.5 centimeters (1″) shorter than the cavity length. A forward portion 126 length of 5″ would be preferred for a 6″ cavity 125; a forward portion 126 length of 6″ would be preferred for a 7″ cavity, etc. The length of the forward portion for typical oil nozzle inserts in the prior art were generally about three to four inches in length. At the preferred length of approximately 9 inches, the tip 130 of the forward portion 126 extends into the flame cavity 125 such that the tip 130 will be about three to four inches from the front face 122 of the burner block 102, or approximately 30% to 40% of the cavity length from the front face 122. For the typical burner block having a flame cavity 125 with a length of about 10 inches, the tip 130 of a nine inch long forward portion 126 will terminate approximately 5 inches (or one half of the length of flame cavity 125) into the flame cavity 125. A typical prior art oil nozzle insert had a tip that terminates at the back end of the burner block, which is between about nine to ten inches from the front face of the burner block. The extension of the oil nozzle 106 insert such that the tip 130 is distanced from the back end 124 of the burner block 102 causes the flame emanating from the tip 130 of the burner block to be a further distance from the back end 124 of the burner block. In preferred embodiments, the tip is in the front 50% of the burner cavity 125. So if the cavity 125 is 8″ long, the forward portion 126 would be at least 5 inches long for the tip to extend into the front 50% of the cavity. This reduces the heat exchange through the back of the burner block and through the exterior walls of the furnace. Consequently, there is less likelihood of damage, such as erosion damage, to the burner block and the furnace walls due to the high heat exchange.

A preferred materials for the nozzle is stainless steel.

The prior art nozzle caused wear of the burner cavity so that the burner block 102 needed to be replaced after 2 days, whereas during a one-week test, a longer nozzle of FIG. 2 did not cause any appreciable wear during the week until the longer nozzle was removed from service.

Although the invention has been described in terms of exemplary embodiments, it is not limited thereto. Rather, the appended claims should be construed broadly, to include other variants and embodiments of the invention which may be made by those skilled in the art without departing from the scope and range of equivalents of the invention.

Claims

1. A burner assembly for a furnace comprising:

a burner block having a flame cavity with a flame cavity length; and

an oil nozzle insert having a tip that extends into the flame cavity by a distance of greater than one tenth of the flame cavity length.

2. The burner assembly of claim 1, wherein the tip extends approximately one half of the flame cavity length into the flame cavity.

3. The burner assembly of claim 1, wherein the flame cavity of the burner block has a length of between about nine to ten inches, and the oil nozzle insert has a tip that terminates a distance of greater than one inch into the flame cavity.

4. The burner assembly of claim 3, wherein the tip terminates a distance of greater than one inch into the flame cavity.

5. The burner assembly of claim 3, wherein the tip terminates approximately five inches into the flame cavity.

6. A burner assembly for a furnace comprising:

a burner block having a front face and a flame cavity with a flame cavity length; and

an oil nozzle insert having a tip that terminates less than 90% of the flame cavity length from the front face of the burner block.

7. The burner assembly of claim 6, wherein the oil nozzle insert has a tip that terminates at a distance from the front face of the burner block of between about 30% to 40% of the flame cavity length.

8. The burner assembly of claim 6, wherein the oil nozzle insert has a tip that terminates between about three to four inches from the front face of the burner block.

9. The burner assembly of claim 6, wherein the tip terminates less than nine inches from the front face of the burner block.

10. A burner assembly for a furnace comprising:

a burner block having a front face and a flame cavity with a flame cavity length of about five inches or longer; and

an oil nozzle insert having a tip that extends into the cavity and terminates at a distance from the front face of the burner block of between about 30% to 40% of the flame cavity length.

11. The burner assembly of claim 10, wherein the oil nozzle insert has a forward portion with a length about one inch less than the flame cavity length.

12. The burner assembly of claim 10, wherein the oil nozzle insert has a tip that terminates between about three to four inches from the front face of the burner block.