Burner Tips

Abstract

A burner tip, and method of manufacture, has a support layer with an external surface exposed to combustion reactions and an unexposed internal surface defining at least one a passage therethrough to deliver fuel and combustion gasses, and a thermal protective layer disposed on at least part of the unexposed surface of the burner tip support layer. The thermal protective layer 22 has from about 5% to about 40% of an inorganic adhesive, from about 45% to about 92% of a filler, and from about 1% to about 20% of one or more emissivity agents.

What is claimed is: 
     
         1 . A burner tip, comprising:
 a burner tip support layer, comprising a metallic substrate, with an external surface directly exposed to the combustion reactions and an unexposed internal surface defining at least one opening therethrough; and   a thermal protective layer disposed on the unexposed internal surface of said burner tip support layer, wherein said thermal protective layer has   from about 5% to about 40% of an inorganic adhesive taken from the group consisting of an alkali/alkaline earth metal silicate taken from the group consisting of sodium silicate, potassium silicate, calcium silicate, and magnesium silicate, from about 45% to about 92% of a filler, and from about 1% to about 20% of one or more emissivity agents.   
     
     
         2 . The burner tip according to  claim 1 , further comprising:
 a thermal protective layer is disposed on said external surface of said burner tip support layer.   
     
     
         3 . The burner tip according to  claim 1 , wherein:
 said metallic substrate is taken from the group consisting of iron, aluminum, alloys, steel, and cast iron.   
     
     
         4 . The burner tip according to  claim 1 , wherein:
 said thermal protective layer further comprises   from about 1.0% to about 5.0% of a stabilizer;   from about 1.0% to about 5.0% of a stabilizer taken from the group consisting of bentonite, kaolin, magnesium alumina silica clay, tabular alumina, and stabilized zirconium oxide;   up to about 0.25% of a surfactant;   a colorant; or   combinations thereof.   
     
     
         5 . The burner tip according to  claim 1 , wherein:
 said inorganic adhesive is taken from the group consisting of an alkali/alkaline earth metal silicate taken from the group consisting of sodium silicate, potassium silicate, calcium silicate, and magnesium silicate;   said filler is taken from the group consisting of silicon dioxide, aluminum oxide, titanium dioxide, magnesium oxide, calcium oxide, and boron oxide;   said one or more emissivity agents are taken from the group consisting of silicon hexaboride, boron carbide, silicon tetraboride, silicon carbide, molybdenum disilicide, tungsten disilicide, zirconium diboride, cupric chromite, and metallic oxides;   said emissivity agents are a metal oxide taken from the group consisting of iron oxide, magnesium oxide, manganese oxide, chromium oxide, and derivatives thereof; or   combinations thereof.   
     
     
         6 . The burner tip according to  claim 1 , wherein:
 said thermal protective layer contains   a. from about 5% to about 40% of an inorganic adhesive, the inorganic adhesive is taken from the group consisting of an alkali/alkaline earth metal silicate taken from the group consisting of sodium silicate, potassium silicate, calcium silicate, and magnesium silicate; from about 45% to about 92% of a filler, the filler taken from the group consisting of silicon dioxide, aluminum oxide, titanium dioxide, magnesium oxide, calcium oxide, and boron oxide; and from about 1% to about 20% of one or more emissivity agents taken from the group consisting of silicon hexaboride, boron carbide, silicon tetraboride, silicon carbide, molybdenum disilicide, tungsten disilicide, zirconium diboride, cupric chromite, and metallic oxides; or   b. from about 5% to about 40% of an inorganic adhesive, the inorganic adhesive taken from the group consisting of an alkali/alkaline earth metal silicate taken from the group consisting of sodium silicate, potassium silicate, calcium silicate, and magnesium silicate; from about 45% to about 92% of a filler, the filler taken from the group consisting of silicon dioxide, aluminum oxide, titanium dioxide, magnesium oxide, calcium oxide, and boron oxide; and from about 1% to about 20% of one or more emissivity agents taken from the group consisting of silicon hexaboride, boron carbide, silicon tetraboride, silicon carbide, molybdenum disilicide, tungsten disilicide, zirconium diboride, cupric chromite, and metallic oxides; and from about 1% to about 5% of a stabilizer taken from the group consisting of bentonite, kaolin, magnesium alumina silica clay, tabular alumina, and stabilized zirconium oxide.   
     
     
         7 . The burner tip according to  claim 1 , wherein:
 from about 2% to about 20% of a first emissivity agent taken from the group consisting of, boron carbide, silicon carbide powder, silicon tetraboride, molybdenum disilicide, tungsten disilicide, zirconium diboride, cupric chromite, and metal oxides; and   from about 0.5% to about 3.5% of a second emissivity agent consisting of silicon hexaboride.   
     
     
         8 . The burner tip according to  claim 1 , further comprises:
 a plenum comprising a metallic substrate extending from the burner tip, having an external exposed surface, and an internal unexposed surface, wherein said plenum further has a thermal protective layer disposed on the internal unexposed surface.   
     
     
         9 . The burner tip according to  claim 1 , further comprising:
 multiple openings defined therethrough having passages extending therefrom, each passage in communication with fuel or combustion gas sources; or   multiple passage defined therethrough, forming a mix zone within the burner tip adjacent said opening, each passage in communication with fuel or combustion gas sources.   
     
     
         10 . The burner tip according to  claim 1 , wherein:
 said thermal protective layer comprises   from about 5% to about 40% of an alkali/alkaline earth metal silicate taken from the group consisting of sodium silicate, potassium silicate, calcium silicate, and magnesium silicate;   from about 45% to about 92% of a filler taken from the group consisting of silicon dioxide, aluminum oxide, titanium dioxide, magnesium oxide, calcium oxide, and boron oxide: and   from about 1% to about 20% of a first emissivity agent taken from the group consisting of, boron carbide, silicon carbide powder, silicon tetraboride, molybdenum disilicide, tungsten disilicide, zirconium diboride, cupric chromite, and metal oxides, and from about 0.5% to about 3.5% of a second emissivity agent consisting of boron silicide (silicon hexaboride), or   from about 1% to about 20% of one or more emissivity agents taken from the group consisting of silicon hexaboride, boron carbide, silicon hexaboride, silicon tetraboride, silicon carbide powder, molybdenum disilicide, tungsten disilicide, zirconium diboride, cupric chromite, and metal oxides.   
     
     
         11 . The burner tip according to  claim 10 , wherein:
 said thermal protective layer further comprises from about 1% to about 5% of a stabilizer taken from the group consisting of bentonite, kaolin, magnesium alumina silica clay, tabular alumina, and stabilized zirconium oxide;   said emissivity agents are a metal oxide taken from the group consisting of iron oxide, magnesium oxide, manganese oxide, chromium oxide, and derivatives thereof; or   combinations thereof.   
     
     
         12 . The burner tip according to  claim 1 , further comprising:
 a means for mixing fluids having   fins incorporated into the opening;   fins incorporated into the passage extending from the opening; and   combinations thereof.   
     
     
         13 . A method of manufacturing a burner tip having a thermal protective layer, comprising:
 providing a burner tip having a metallic support layer with an external surface which will be exposed directly to the combustion reaction, and an internal surface which will be unexposed to the combustion reactions defining at least one opening therethrough;   mixing a thermal protective coating containing
 a. from about 6% to about 40% of an inorganic adhesive, from about 23% to about 46% of a filler, from about 1% to about 10% of one or more emissivity agents, and from about 18% to about 50% water; and 
   applying the mixed thermal protective coating to the unexposed surface using a spray gun to form a thermal protective layer from about 2 mils (5 microns) to about 10 mils (254 microns) thick.   
     
     
         14 . The method of  claim 13 , further comprising:
 the thermal protective layer further comprises   from about 0.5 percent to about 2.4 percent of a stabilizer;   up to about 0.25% of a surfactant;   from about 0.5 percent to about 2.4 percent of a stabilizer taken from the group consisting of bentonite, kaolin, magnesium alumina silica clay, tabular alumina, and stabilized zirconium oxide;   a colorant; or   combinations thereof.   
     
     
         15 . The method of  claim 13 , wherein:
 the inorganic adhesive is taken from the group consisting of an alkali/alkaline earth metal silicate taken from the group consisting of sodium silicate, potassium silicate, calcium silicate, and magnesium silicate;   the filler is taken from the group consisting of silicon dioxide, aluminum oxide, titanium dioxide, magnesium oxide, calcium oxide, and boron oxide;   the one or more emissivity agents are taken from the group consisting of silicon hexaboride, boron carbide, silicon tetraboride, silicon carbide, molybdenum disilicide, tungsten disilicide, zirconium diboride, cupric chromite, and metallic oxides;   the emissivity agents are a metal oxide taken from the group consisting of iron oxide, magnesium oxide, manganese oxide, chromium oxide, and derivatives thereof; or   combinations thereof.   
     
     
         16 . The method of  claim 13 , wherein:
 the spray gun is taken from the group consisting of an high volume low pressure spray gun or an airless spray gun.   
     
     
         17 . The method of  claim 13 , further comprising:
 agitating the solution of thermal protective coating prior to applying.   
     
     
         18 . The method of  claim 13 , further comprising:
 rotating the direction of spray to facilitate an even thickness.   
     
     
         19 . The method of  claim 13 , further comprising:
 allowing the thermal protective layer to air dry from about two to about four hours.   
     
     
         20 . The method of  claim 13 , further comprising:
 preparing the exposed surface first by   cleaning, grit blasting, or combinations thereof.