Abstract:
A forged copper burner enclosure capable of being mounted within the side wall of a steel melting furnace for the purpose of providing an improved cooling characteristic to a burner lance. The burner enclosure is provided with a central passage adapted to receive a burner lance for injecting oxygen into the batch of molten metal of an electric arc furnace. The forged burner enclosure is positioned such that only a solid forged copper face is on the furnace side when installed. The burner enclosure has an optional through hole which can be used for the purpose of treating the metal melt with particulate supply ranging from slag forming materials to metallurgical materials. The burner enclosure further has a number of coolant holes and tubes which provide a unique bidirectional flow of cooling fluid through each hole and increases cooling fluid velocity while reducing stalling and hot spots of the cooling fluid thereby providing better heat transfer and physical characteristics over cast or weld-assembled burner enclosures.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     Not applicable. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention generally relates to an improved liquid cooled forged burner enclosure for holding a burner or lance to inject oxygen into an electric arc furnace during the steel making process and more particularly to a cooling arrangement for a burner enclosure surrounding a central duct for the supply of oxygen which is blown into the bath of molten steel. 
     2. Description of the Prior Art 
     In an effort to increase efficiency of the steel producing process and reduce the overall manufacturing costs, steel producers have, for the past few years, evolved to using oxidizing gases, preferably oxygen in the melting, refining, and processing steps of making steel in an electric arc furnace. Oxygen is used at different points in the melting and refining process in an electric arc furnace. Initially, it may be used to add heat during the pre-heating phase of a melt or to assist in the formation of a foamy slag during or at the end of the melting phase, and to de-carbonize the molten bath during refining. This practice has resulted in the creation of a relatively significant industry relating to the practice of injecting gases as well as solids into an electric arc steel making furnace during the steel manufacturing process. 
     The practice of injecting gases into a steel making furnace has progressed from mechanically controlled injectors to injectors mounted in the sidewall of a furnace to the current emerging technology of fixed position burners, that is, injectors that protrude out into the furnace in a copper “tile box”, “burner enclosure”, “nose panel”, or various other terms. 
     Metz et al., U.S. Pat. No. 4,369,060, discloses a plurality of agitating injectors incorporated in its refractory lining, for blowing the agitated gas, located in the bottom of the crucible, along a circle in the immediate vicinity of the sidewall of the furnace lining. Chang, U.S. Pat. No. 4,047,936, discloses imbedded concentric double-tube injectors for introducing oxygen enveloped by a shielding gas into the interior of the steel bath to oxidize impurities. Also, an overhead water cooled lance may be used to enter the vessel in the vertical position through the mouth opening. The overhead lance is attached to a rotary arm which in turn is supported by a sliding column with the lance entering the converter through a hole in the hood by rotating the arm clockwise and leaving the converter by rotating the arm counter-clockwise. Obviously, the life time of such mechanically controlled injectors or injectors built in the sidewall of the furnace itself is equal to that of the crucible and thereafter, the furnace lining needs to be rebuilt. Further, overhead water cooled lances such as disclosed by Metz, et al., while being able to be submerged directly into the molten bath to efficiently place gases and materials in a reaction zone are cumbersome and must be lowered vertically through the top of a steel making vessel. Because of their weight and size, they are not very useful to reach or be positioned for effective injection in an electric arc furnace. 
     These early problems evolved into the introduction of fixed position burners/injectors that protrude out into the furnace. When injecting gas into a liquid pool, it is desirable to have as much gas as possible flow into the liquid to carry out the intent/objective of the gas injection. When a nozzle of a burner lance is spaced too high above the liquid surface, then the gas impinging on the surface of the liquid will be deflected at the surface of the liquid and will not enter the liquid pool. Further, such action causes splashing of the liquid which can result in heat damage to the burner. One conventional method for reducing heat damage to a burner is to circulate a coolant such as water through the burner. Since most burners are made from copper castings or fabricated copper/steel weldments, the burner design itself is considerably more complicated to accommodate the coolant passages. Further, the cooling channels of the burner enclosure associated with the burner, due to the nature of the casting process, develop isolated “hot spots” which is an inherent design characteristic. Also, such mold design issues can cause stalling of the coolant flow in reduced service life due to wear of the casting. Also, as stated above, such burners are prone to damage as a result of the hot melt splashing on the burner tip in the harsh environment. 
     To avoid severe damage to the equipment, attempts have been made to recess the burner from the furnace or combustion zone. Generally, in such cases, the burner is recessed within a cavity in the furnace wall. In such arrangement, less heat or energy from the combustion zone is radiated to the burner surface and thus a coolant may not be needed by relying on the coolant passing through the furnace wall, surrounding the cavity in which the burner is recessed. Heat transfer by the radiation from the furnace decreases as the burner is withdrawn into the furnace wall cavity. However, with a burner recessed within a cavity, combustion may, and usually does occur within the cavity thus generating heat close to the burner surface and again increasing heat to the burner which may cause corrosion of the castings and reduce its efficiency. Further, if the burner is a weldment, such are prone to weld failures, which may cause water to leak into the furnace in the case of a water cooled burner. Also, recessing the burner in the furnace wall increases the distance to the molten metal, reducing its efficiency 
     Shver, U.S. Pat. No. 6,289,035 discloses such mounting arrangement. In Shver, the mounting block is fluid cooled to survive the hostile environment of the electric arc furnace. During the refining or decarburizing phase, the metal continues to be heated by the arc until slag forming materials combine with impurities in the iron carbon melt and rise to the surface as slag. When the iron carbon melt reaches a boiling temperature, the charged carbon in the melt combines with any oxygen present in the bath to form carbon monoxide bubbles which rise to the surface of the bath. At this point, supersonic flows of oxygen are blown at the bath with the fixed burner lance to provide a de-carbonization of the bath by oxidation of the carbon contained in the bath. By injecting the bath with oxygen, the carbon content of the bath is reduced to under two percent (2%) whereby the iron carbon melt becomes steel. The mounting block protects the burner apparatus from the harsh environment. 
     What is needed is a burner enclosure having an outer configuration which can be modified to fit an existing opening in the wall of an electric arc furnace. The burner enclosure provides a central passage adapted to receive a lance or burner injecting oxygen into the bath of molten metal of an electric arc furnace. The burner enclosure should not have welds on the furnace side to minimize the chance of coolant water leaking into the furnace. The coolant flow in the burner enclosure must be efficient and uniform to avoid stalling and hot spots so as to provide better heat transfer and physical characteristics over cast burner enclosures. 
     SUMMARY OF THE INVENTION 
     The invention provides a forged burner enclosure for a burner, lance, or similarly named apparatus and an improved configuration for mounting such apparatus in an existing opening of the wall of an electric arc welding furnace for steel making. 
     In the preferred embodiment, the burner enclosure is fabricated from a copper forging which is machined with a centrally disposed through hole along the longitudinal axis of the burner enclosure and is adapted to receive a lance or burner for providing oxygen to an electric arc furnace. Surrounding this central opening or hole is a machined arcuate counterbore. Within the arcuate counterbore, are machined a plurality of equal sized kidney-shaped arcuate compartments which are circumferentially equally spaced around the central opening or hole. Within each arcuate compartment is an even number of evenly spaced deep drilled blind holes. (If the enclosure has 10 deep drilled blind holes, there will be 5 kidney-shaped arcuate compartments, each having 2 deep drilled blind holes; if 12 deep drilled blind holes are machined in the enclosure, there can be either 3 or 6 kidney-shaped arcuate compartments, and each compartment will have four or two deep drilled blind holes respectively; while if six deep drilled blind holes are present, there will be three arcuate compartments, each having 2 deep drilled blind holes.) The preferred embodiment shown has three kidney-shaped arcuate compartments and 12 deep drilled blind holes, therefore each of the equally spaced arcuate compartments will have four evenly spaced deep drilled blind holes. 
     In each arcuate compartment is sealably mounted a header plate which is shaped to conform to the arcuate compartment periphery. Further, each header plate has four evenly spaced apertures that communicate with four tubes that are sealably mounted and aligned with respective blind holes. The tubes extend outwardly from the bottom of the header plate. The tubes are shorter in length than the depth of each of the deep drilled blind holes machined into the burner enclosure. Therefore, each hole has a chamber between the end of the tube and the bottom wall of the blind hole so that water flowing down each tube can flow through the chamber and back up towards the header plate between the outside diameter of the tube and the insider diameter of the wall of the deep drilled blind hole in the burner enclosure. Since the deep drilled blind holes are considerably larger than the outside diameter of the tube mounted in each hole a continuous flow path of coolant is established for each tube and deep drilled blind hole combination. The flow path allows cooling water to flow down inside the tube into the chamber at the bottom of each hole where the coolant is further directed to flow upward between the outer wall of the tube and the inner wall of the hole. 
     In order to establish a continuous flow through the entire burner enclosure each header plate is provided with a divider plate which separates the first two of the four tubes from the adjacent two tubes of the four tubes mounted to each header plate. With the divider plates sealably secured in place, the space above the header plate is divided into four separate chambers once a cover plate is sealably mounted to the burner enclosure. Also, since the header plate is mounted into the arcuate compartment at a location above the bottom surface of the arcuate compartment a chamber is created underneath the header plate which permits communication between the four holes common to each kidney-shaped arcuate compartment. 
     Therefore, it is an object of the invention to provide a burner enclosure for an oxygen lance or burner which is durable and not prone to erosion and cracking or weld failures. 
     It is yet a further object of the invention to provide a burner enclosure for an oxygen lance or burner which provides better strength and heat transfer. 
     It is still a further object of the invention to provide a burner enclosure for an oxygen lance or burner for an electric arc furnace for steel making which can be modified to fit existing furnace sidewalls. 
     It is yet a further object of the invention to provide a burner enclosure for an oxygen lance or burner which incorporates machined water channels for uniform coolant to flow through the burner enclosure thereby eliminating stalling and hot spots and increasing the life of the burner enclosure. 
     It is still a further object of the invention to maintain a uniform cooling water flow through the burner enclosure in order to eliminate stalling and turbulence in critical areas. 
     It is still a further object of the invention to maintain coolant flow at a high velocity to prevent any solid deposits from clogging cooling passages. 
     There are other objects, aspects, and features of the invention that will be more clearly understood and better described when the following detailed description is read in conjunction with the attached drawings. 
    
    
     
       BRIEF DESCRIPTIONS OF THE DRAWINGS 
         FIG. 1  is a perspective view of the forged burner housing, header and tube assemblies, and end cover with inlet and outlet ports and fittings for the coolant fluid; 
         FIG. 2  is a partial sectional side view of the mounting arrangement of the invention in the furnace wall of an electric arc furnace; 
         FIG. 3  is an end view of the forged burner housing illustrating the machined cooling passages and upper arc segment chambers for mounting the header plates; 
         FIG. 4  is a cross-section side view of the forged burner housing taken along section  4 - 4  of  FIG. 3 ; 
         FIG. 5  is a perspective exploded view of the three divider plates, header and tube assemblies, cover, inlet and outlet fittings that are mounted into the burner housing to establish the various chambers through which flow a continuous stream of coolant; 
         FIG. 6  is an end view of the forged burner housing with the three header and tube assemblies installed in the burner housing and the end cover removed; 
         FIG. 7  is a planar layout of the hole pattern of the burner enclosure to illustrate the flow pattern of the coolant water through the burner enclosure; 
         FIG. 8A  is an end view of the second embodiment of a forged burner housing illustrating the machined cooling passages and peripherally spaced recessed compartments for mounting header and tube assemblies; 
         FIG. 8B  is an end view of the forged burner housing with the three header and tube assemblies installed in the burner housing and the end cover removed of the second embodiment; and 
         FIG. 8C  is a perspective exploded view of the three divider plates, header and tube assemblies, cover, inlet and outlet fittings that are mounted into the burner housing to establish the various chambers through which flow a continuous stream of coolant within the second embodiment. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     In  FIG. 1  (as assembled) and  FIG. 5  (exploded view), there is shown a forged burner enclosure  20  in perspective consisting of a burner housing  21  with three concentrically spaced header and tube assemblies  40  which mount into deep drilled blind holes  28  at the top of arcuate compartments  26   a ,  26   b , and  26   c  in the burner housing  21 ; and a cover plate  70  for covering the header and tube assemblies  40  containing the coolant inlet port  72  and coolant outlet port  74  with their respective inlet  76  and outlet  78  coolant fittings welded concentrically to their respective ports. The complete assembly is accomplished by welding each of the three header and tube assemblies  40  in place after they are inserted into the burner housing  21  and further welding the cover plate  70  at the top of the arcuate counterbore  25  provided in the burner housing  21  as will be described hereinafter. After assembly, the forged burner enclosure  20  is mounted in the sidewall of the shell of an electric arc furnace (EAF) as shown in  FIG. 2 , with a burner lance  23  mounted in the central passageway of the forged burner enclosure  20 . Depending on the configuration of the furnace  10 , the forged burner enclosure  20  may be mounted anywhere in the sidewall  22  of the furnace. Further, the furnace  10  may have more than one forged burner enclosure  20  mounted around its periphery, depending upon its size, configuration, and melting power. Generally, such forged burner enclosure(s)  20  are located at the cold spots in the furnace  10  to assist with the melting of the charge. These cold spots are different for DC (direct current) furnaces usually having one electrode and AC (alternating current) furnaces having three electrodes, and may be different even between these furnaces depending on the size, manufacturer, and operating procedure of the furnace. 
     The forged burner enclosure  20  is adapted to operate in several different modes to provide auxiliary heating, metal refining, and other processing capabilities in electric arc furnaces (EAF), or similar metal melting, refining, or processing furnaces. In  FIG. 2 , which illustrates a partial side view, the EAF  10  melts ferrous scrap  11  by means of an electric arc  12  produced from one or more electrodes  13  to collect as a molten metal melt  14  at its lowest point or hearth  15 . The hearth  15  is made of refractory material to withstand the intense heat of the molten metal  14 . The hearth  15  is surrounded by an upper wall housing which consists of a series of arcuate fluid cooled panels  16 . These fluid cooled panels  16  can be of several different conventional arrangements such as illustrated in the preferred embodiment with an outer shell member  17  and a plurality of cooling coils  18 . The charge or molten metal melt  14  is generally covered with variable amounts of slag  19  as a result of chemical reactions between the molten metal melt  14  and slag  19  forming materials added to the furnace during the melting process of the metal. 
     The forged burner enclosure  20  is normally mounted through an opening in the fluid cooling coils  18  of the outer shell member  17  of the furnace  10 . The forged burner enclosure  20  is fluid cooled and generally is bolted into some form of mounting plate or rectangular shaped mounting block usually retrofitted to an existing furnace or integrated into the wall of a newly designed furnace. The forged burner enclosure  20  is received into a mounting aperture of the mounting plate so that the discharge opening of the burner lance  23  mounted within the central disposed through-passage or opening  24  of the burner housing  21  is extended beyond the edge of the refractory hearth  15 . This permits the flow of materials from the discharge opening of the burner lance  23  to not interfere with the refractory material so that degradation of the refractory material is avoided. Since the forged burner enclosure  20  is fluid cooled, it can withstand the high temperatures of the internal areas of the furnace  10 . This allows the burner enclosure  20  to be brought closer to the molten metal melt  14  and so that it can be more efficient in its operation. The forged burner enclosure  20  is slanted downward at an angle, preferably between 20-50 degrees, to direct the flange of the burner lance  23  towards the molten metal melt  14  in the hearth  15  of the furnace  10 . In addition to its downward inclination, the forged burner enclosure  20  may also be directed from a radial position, preferably 0-20 degrees tangentially. 
     The forged burner enclosure  20  is designed to receive a burner lance  23 , shown in  FIG. 2 , centrally mounted in central opening  24  of the burner housing  21  as shown in  FIG. 4 . The burner housing  21  can accommodate a variety of burner lances  23  from various manufacturers. The central opening  24  is customized to receive various sizes and configurations of burner lances  23 . In the preferred embodiment shown in cross-section in  FIG. 4 , the central opening  24  has a tapered area complementary with a tapered area on a specific burner lance  23  used to locate the burner lance (not shown) within the burner housing  21  which in turn is mounted in the sidewall  22  of the electric arc furnace  10  as shown in  FIG. 2 . 
     Some burner lances  23  are designed with water cooling passages surrounding the gas and fuel supply passages. Other types of burner lances  23  used in conjunction with the forged burner enclosure  20  of the invention have no coolant passages and rely entirely on the water cooling arrangement of the forged burner enclosure  20 . 
     The burner lance  23  is supplied with two utilities from an oxidizing gas supply and a fuel supply (not shown). The oxidizing gas supply provides commercially pure oxygen, although a mixture of oxygen with air or another gas is not uncommon. The fuel supply is generally natural gas but here again, a combination of fuel fluids or gases maybe used. The burner housing  21  may optionally have a longitudinal through-hole  30  as shown in  FIG. 4  which serves to provide the particular supply, ranging from slag forming materials to metallurgical materials. The operation and timing of these various utilities is generally controlled by a programmed logic controller as is well known in the prior art. 
     With specific reference to  FIGS. 3 and 4 , the forged burner housing  21  illustrates one arcuate counterbore  25  and three machined arcuate compartments  26   a ,  26   b , and  26   c  which are concentric to the arcuate counterbore  25  and located in the upper end of the forged burner housing  21 . The arcuate counterbore  25  and the three machined arcuate compartments  26   a ,  26   b ,  26   c  are designed to direct water flow within the burner enclosure  20  which will hereinafter be illustrated. Each arcuate compartment  26   a ,  26   b ,  26   c  contains four deep drilled blind holes  28 . The deep drilled blind holes  28  are each drilled to within approximately 2½ inches from the bottom end  29  of the burner housing  21  so as to present a solid forged copper face as a buffer zone between the intense heat in the furnace  10  and the coolant flowing through these blind holes  28 . Monitoring of the gradual wearing away of the copper face allows time to identify potential problems and initiate repair before water leaks occur. The deep drilled blind holes  28  are evenly spaced circumferentially to provide maximum thickness of material between the blind holes  28  and uniform cooling circumferentially around the forged burner enclosure  20 . Further, the deep drilled blind holes  28  are spaced from the outside diameter  35  of the burner housing  21  to provide sufficient structural rigidity to the burner housing  21  so that falling scrap within the furnace  10  that may hit the burner housing  21  will not damage the forged burner enclosure  20 . As disclosed above, the burner enclosure  20  has an optional longitudinal through hole  30  to serve as a particulate supply, ranging from slag forming materials to metallurgical materials, as needed during the steelmaking process. 
     With reference to  FIGS. 3-6 , each of the three arcuate compartments  26   a ,  26   b ,  26   c  in the burner housing  21  are adapted to receive a header and tube assembly  40  as shown in  FIG. 5 . The header and tube assembly  40  is manufactured from stainless steel to prevent clogging of the water passages due to oxidation buildup. Each header and tube assembly  40  is made with the respective number of tubes  52 , a header plate  42 , and a divider plate  48  as shown in  FIG. 5 . The header plate  42  has a corresponding number of apertures  43  which are aligned with each deep drilled blind hole  28  of the burner housing  21 . The tubes  52  are aligned to each header plate aperture  43  and sealably welded to the header plate  42 . The divider plate  48  is welded to the top surface  50  of the header plate  42 . When each of the header and tube assemblies  40  are mounted in the respective arcuate compartments  26   a ,  26   b ,  26   c  of the burner housing  21 , the header plate  42  comes to rest on a counterbored shoulder  33  machined at the top of each arcuate compartment  26   a ,  26   b ,  26   c  as shown in  FIG. 4 . After each header and tube assembly  40  is welded into a respective arcuate compartment  26   a ,  26   b ,  26   c , three watertight separated chambers  46   a ,  46   b ,  46   c , are created along the lower level, below the welded header plate  42  and above the bottom surface of each arcuate compartment  26   a ,  26   b ,  26   c . Each chamber  46   a ,  46   b ,  46   c  having the form of each arcuate compartment  26   a ,  26   b ,  26   c.    
     The divider plates  48 , as welded to each of the header plates  42  result in the formation of four upper arcuate compartments A, B, C, D as shown in  FIG. 6   a . These four upper compartments A, B, C, D combine with the three lower chambers and tubes  52  mounted in the deep drilled blind holes  28  of the burner housing  21  to provide continuous flow of coolant through the forged burner enclosure  20 . This can only be accomplished by the use of a cover plate or cap  70  which is welded in place to the top of the arcuate counterbore  25  and each divider plate  48  of each header and tube assembly  40  to secure a watertight forged burner enclosure  20 . Each of the header and tube assemblies  40  welded in their respective arcuate compartments  26   a ,  26   b ,  26   c  with the cover plate  70  securely welded at the top of the arcuate counterbore  25  creates four upper chambers  44   a ,  44   b ,  44   c ,  44   d . The cover plate  70  has a coolant inlet port  72  and a coolant outlet port  74 . The coolant inlet fitting  76  is welded to the cover plate  70  aligned to the coolant inlet port  72 . The coolant outlet fitting  78  is welded to the cover plate  70  aligned to the coolant outlet port  74 . The coolant inlet port  72  communicates with the two coolant tubes in the upper chamber  44   a.    
     Each tube  52  is suspended from its header plate  42  into a respective deep drilled blind hole  28  and centered using a spacer  37  located near the end of each tube  52  and welded to the outside diameter of each tube  52  equally spaced at 120° increments around the circumference of the tube as shown in  FIG. 7 . The bottom end of each tube  52  is uniformly spaced from the bottom of its respective deep drilled blind hole  28 . This spacing forces cooling water to the lowest point of the forged burner enclosure  20  without restricting water flow. The preferred embodiment illustrates the use of twelve holes with tubes inserted therein. Larger burner enclosures may require more cooling and additional holes may need to be added. The flow pattern as hereinafter described would be similar. 
       FIG. 7  is a representation of the burner enclosure illustrating, in a flat plane, the various holes, chambers, and coolant flow paths established within the burner enclosure  20 . The three lower chambers  46   a ,  46   b , 46   c  are located between the bottom surface  32  of the header plate  42  mounted against the counterbored shoulder  33  at the top of each arcuate compartment  26   a ,  26   b ,  26   c  and the bottom surface  27  of each of the arcuate compartments  26   a ,  26   b ,  26   c . The cover plate  70  is welded to the burner housing  21  as well as each of the divider plates  48  to create the watertight upper chambers  44   a ,  44   b ,  44   c ,  44   d . For purposes of clarity the spacers  37  attached to the bottom end of each tube  52 , to maintain centering of the tube  52  within each deep drilled blind hole  28  are only shown on one of the tubes  52  of  FIG. 7 . 
     As coolant enters the inlet port  72  of the cover plate  70 , it is forced to flow into chamber  44   a  downward into the two tubes  52  that communicate with the upper chamber  44   a . As the coolant reaches the bottom end of each of the two tubes  52 , it impinges against the bottom end  36  of the deep drilled blind holes  28  and continues to flow upwards in the space between the outside diameter  31  of each of the two tubes  52  and the inside diameter  34  of each of the first two deep drilled blind holes  28  located in lower chamber  46   a . When the upward flowing coolant reaches the lower chamber  46   a , it can no longer rise further upward since the welded header plate  42  made the lower chamber  46   a  watertight, the coolant must now flow along the lower chamber  46   a  until it encounters the next two deep drilled blind holes  28  in the lower chamber  46   a . Again, since the coolant cannot flow upward it will begin to flow downward between the outside diameter  31  of the tubes  52  and the inside diameter  34  of the next two deep drilled blind holes  28  in lower chamber  46   a . As the coolant flows to the bottom of the deep drilled blind holes  28 , it encounters the bottom end  36  of the deep drilled blind holes  28  and impinges there against causing the coolant to flow upward inside the last two tubes  52  located in the arcuate compartment  26   a  and rise upwards towards the upper chamber  44   b . The upper chamber  44   b  is in fluid communication with the last two tubes  52  of the header and tube assembly  40  that is mounted in arcuate compartment  26   a  as well as the first two tubes  52  of the header and tube assembly  40  that is mounted in arcuate compartment  26   b . Therefore, the coolant rising in the last two tubes  52  in arcuate compartment  26   a  flows into the upper chamber  44   b  and spills over into the first two tubes  52  of the header and tube assembly  40  mounted in arcuate compartment  26   b . As discussed above relative to the first two tubes  52  in upper chamber  44   a , the cycle now repeats itself, that is, the incoming coolant flows downward in the first two tubes  52  of arcuate compartment  26   b  until at the bottom of the tubes  52 , the coolant encounters the bottom end  36  to impinge there against. The coolant then begins to flow upwards between the outside diameter  31  of the two tubes and the inside diameter  34  of the deep drilled blind holes  28  until it rises to the lower chamber  46   b . As in the lower chamber  46   a , the flow within the lower chamber  46   b  is in fluid communication with the next two blind holes  28  which are located in arcuate compartment  26   b . Coolant flow continues downward between the outside diameter of the last two tubes  52  in lower chamber  46   b  and the inside diameter  34  of the deep drilled blind holes  28  and returns upward within the last two tubes  52  of arcuate compartment  26   b  into the upper chamber  44   c . Upper chamber  44   c  is in fluid communication with the last two tubes  52  of the header and tube assembly  40  mounted in arcuate compartment  26   b  as well as the first two tubes of the header and tube assembly  40  mounted in arcuate compartment  26   c . Therefore, the coolant rising in the last two tubes  52  mounted in arcuate compartment  26   b  flow into upper chamber  44   c  and continues to flow downwards in the first two tubes  52  of the header and tube assembly  40  which is mounted in arcuate compartment  26   c . The coolant continues along this flow pattern through the remainder of the tubes and chambers until it flows into upper chamber  44   d  and exits the burner housing  21  through the coolant outlet port  74 . 
     In order to obtain uniform coolant velocity, avoid turbulence, or prevent solid deposits from clogging along any of the cooling passages of the burner enclosure, there are certain cross-sectional area relationships that must be established. For example, the effective cross-sectional area of the two stainless tubes  52  in parallel is approximately equal to or less than the effective cross-sectional area of the coolant inlet port  72 . Also, the cross-section of the area between each outside diameter  31  of each tube  52  and each inside diameter  34  of each deep drilled blind hole  28  is approximately equal to the cross-section of the inside diameter of each stainless tube  52  to assure uniform coolant flow. Uniform flow helps avoid stalling and turbulence in the most critical areas of the forged burner enclosure  20 , which can cause premature failure in copper castings that do not utilize an internal cooling coil. Uniform flow within the forged burner enclosure  20  also allows for higher velocity flow of the coolant so that solid deposits are prevented from clogging cooling passages. In each of the lower chambers  26   a ,  26   b ,  26   c , the coolant flows around the tubes  52  before it is advanced to the next upper chamber. Therefore, the cross-sectional area of the chambers  46   a ,  46   b ,  46   c  on each side of each tube  52  passing through it is approximately equal to the total cross-sectional area of the inside area of two parallel tubes  52 , again to prevent turbulence and maintain a uniform flow of the coolant. 
       FIGS. 8A ,  8 B, and  8 C, illustrate another embodiment of the invention wherein the burner housing has a square or rectangular configuration. With reference to  FIGS. 8A ,  8 B, and  8 C, there is shown a forged burner enclosure partial assembly  120  consisting of a burner housing  121  with three peripherally spaced header and tube assemblies  140  which mount into the recessed compartments  126   a ,  126   b , and  126   c  in the burner housing  121 . The tubes  152  extend into respective blind holes  128  drilled into the burner housing  121 . A cover plate for covering the header and tube assemblies containing a coolant inlet port and coolant outlet port with their respective inlet and outlet coolant fittings is welded in place over the open end of the burner housing similar to the preferred embodiment. (not shown) The complete assembly is accomplished by welding each of the three header and tube assemblies  140  in place after they are inserted into their respective recessed compartments of the burner housing  121  and further welding the cover plate at the top of the step down cavity  125  provided in the burner housing  121  as will be described hereinafter. 
     Like the preferred embodiment, the burner housing  121  may optionally have a longitudinal through-hole  130  which serves to provide the particulate supply, ranging from slag forming materials to metallurgical materials. The operation and timing of these various utilities is generally controlled by a programmed logic controller as is well known in the prior art. 
     This alternate embodiment of the forged burner housing  121  illustrates a step down cavity  125 , having a bottom surface  125   a  in its open end as well as a centrally-disposed through hole  124 . Three machined recessed compartments  126   a ,  126   b , and  126   c  are machined in the bottom surface  125   a  of the step down cavity  125  located in the forged burner housing  121 . The step down cavity  125  and the three machined recessed compartments  126   a ,  126   b ,  126   c  with the use of the header and tube assemblies  140  are designed to direct water flow within the forged burner enclosure  120  which will hereinafter be illustrated. Each recessed compartment  126   a ,  126   b ,  126   c  contains four deep drilled blind holes  128 . The deep drilled blind holes  128  are each drilled to within approximately 2½ inches from the bottom end  129  of the burner housing  121  so as to present a solid forged copper face as a buffer zone between the intense heat in the furnace and the coolant flowing through these blind holes  128 . The deep drilled blind holes  128  are evenly spaced peripherally to provide maximum thickness of material between the blind holes  128  and uniform cooling peripherally about the burner enclosure  120 . Further, the deep drilled blind holes  128  are spaced from the outside surfaces of the burner housing  121  to provide sufficient structural rigidity to the burner housing  121  so that falling scrap within the furnace that may hit the burner housing  121  will not damage the burner enclosure  120 . 
     With reference to  FIG. 8   b , each of the three recessed compartments  126   a ,  126   b ,  126   c  in the burner housing  121  are adapted to receive a header and tube assembly  140 . The header and tube assembly  140  is manufactured from stainless steel to prevent clogging of the water passages due to oxidation buildup. Each header and tube assembly  140  is made with the respective number of tubes  152 , a header plate  142 , and a divider plate  148 . The header plate  142  has a corresponding number of apertures  143  which are aligned with each deep drilled blind hole  128  of the burner housing  121 . The tubes  152  are aligned to each header plate aperture  143  and sealably welded to the header plate  142 . The divider plate  148  is welded to the top surface  150  of the header plate  142 . As in the preferred embodiment, when each of the header and tube assemblies  140  are mounted in their respective recessed compartments  126   a ,  126   b ,  126   c  of the burner housing  121 , the header plate  142  comes to rest on a counterbored shoulder (not shown) machined at the top of each recessed compartment  126   a ,  126   b ,  126   c . After each header and tube assembly  140  is sealably welded into its respective recessed compartment  126   a ,  126   b ,  126   c , three watertight separated chambers  146   a ,  146   b ,  146   c , are created along the lower level, below the level of the header plate  142 . Each chamber  146   a ,  146   b ,  146   c  having the form of each recessed compartment  126   a ,  126   b ,  126   c.    
     The divider plates  148  are welded to each of the header plates  142  which results in the formation of four upper compartments AA, BB, CC, DD as shown in  FIG. 8   b . These four upper compartments AA, BB, CC, DD combine with the three lower chambers  146   a ,  146   b ,  146   c , and tubes  152  mounted in the deep drilled blind holes  128  of the burner housing  121  to provide continuous flow of coolant through the burner enclosure  120 . This can only be accomplished by the use of a cover plate or cap  170  which is welded in place at the top of the step down cavity  125  and each divider plate  148  of each header and tube assembly  140  to secure a watertight burner enclosure  120 . 
     Each tube  152  is suspended from its header plate  142  into a respective deep drilled blind hole  128  and centered using a spacer  137  located near the bottom end of each tube  152  and welded to the outside diameter  131  of each tube equally spaced at 120° increments around the circumference of the tube  152 . The bottom end of each tube  152  is uniformly spaced from the bottom of its respective deep drilled blind hole  128 . This spacing forces cooling water to the lowest point of the forged burner housing  121  without restricting water flow. This embodiment illustrates the use of twelve holes with tubes inserted therein. Larger burner enclosure may require more cooling and additional holes may need to be added. The flow pattern would be similar to the preferred embodiment wherein the inlet port  172  is in communication with the first tube(s) located in the upper chamber AA. The flow would continue as previously described in the preferred embodiment until the last tube(s)  152  flowing to upper chamber DD and in communication with the outlet port  174  of the cover  170 . 
     While the invention has been described in connection with a preferred embodiment, the specification is not intended to limit the scope of the invention to the particular embodiment disclosed. On the contrary, it is intended to cover any alternatives, modifications and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims. For example, the preferred embodiment discloses the coolant outlet to communicate with the upper chamber  44   d . It is entirely foreseeable that as a result of reducing or increasing the number of cooling tubes/holes, the inlet or outlet can communicate directly with the lower chamber as required to reduce stalling or hot spots.