US 3503557 A
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Description (OCR text may contain errors)
H. T. HUTTON, JR
March 31, 1970 MEANS FOR INTRODUCING GAS TO OXYGEN STREAM Filed May 11, 1966 FIG. 5
INVENTOR HARRY T HUTTON. JR.
A T TORNE V United States Patent US. Cl. 239-433 1 Claim ABSTRACT OF THE DISCLOSURE This invention relates broadly to a new apparatus and method for improved intermixing of fluids.
More particularly, this invention relates to an improved method and apparatus whereby fuel gas is added to an oxidizing stream through a porous surface. The invention is particularly applicable to oXy-fuel gas scarfing burners but is not limited thereto.
For removing metal from wide areas it is usual to employ a number of approximately parallel jets which preferably touch one another and merge into a wide stream where they strike the workpiece. The jets may be discharged from separate tips located close to one another transversely across the metal workpiece, or from spaced jet orifices in the face of a block tip, with the jets close enough together to form what is in effect a blanket of oxygen directed against the metal surface. In previous designs fuel metering ports were located adjacent the jet orifices to introduce fuel to the scarfing oxygen stream. The ports were generally locatedin the block tip and were transversely located so as to introduce fuel to the oxygen blanket at spaced locations across the width of the oxygen blanket. The ports comprised a series of discrete openings which were connected to a supply of fuel gas. One of the difiiculties with the prior art form of scarfing burner is that spatter from the work enters the fuel metering ports of the scarfing burner. These ports are generally within perfect line of sight of the work and therefore spatter is free to land in the ends of the ports and clog them. The clogging of the ports results in an uneven mixture of the fuel gas with the oxygen blanket and this in turn causes irregular metal removal.
Scarfing machines are specifically designed to remove surface irregularities and thus it is of paramount importance to provide an even mixture of fuel gas and oxygen across the. surface of the treated metal so that the metal removal is uniform. Clogged fuel ports cannot, therefore, be tolerated and whenever the ports are clogged up the machine must be shut down and cleaned. The cleaning is bothersome and expensive in that each port must be individually treated by re-drilling, etc.
It is accordingly an object of my invention to provide a more eflicient method and apparatus for scarfing metal surfaces. A further object is to alleviate the expense and delay caused by the clogging of the fuel ports in the conventional scarfing burner. Another object of my invention is to provide a new medium thru which fuel gas is uniformly distributed to an oxygen stream.
-While the inventive concepts herein set out were developed while seeking to solve the gas mixing problems of a certain industry, namely, the steel industry, I do not feel that my inventive concepts are restricted to applications in that field. It is accordingly a further object of my invention to provide a more accurate and dependable way to mix fluids which may be utilized in any commercial or private activity.
3,503,557 Patented Mar. 31, 1970 Other features, objects and advantages will appear from the following more detailed description of illustrative embodiments of the invention, which will now be given in conjunction with the accompanying drawings.
In the drawings:
FIGURE 1 is a view of a conventional scarfing burner nozzle, cutting into the surface of a material;
FIGURE 2 is a view, partly in section, of a portion of a conventional nozzle, illustrating the oxygen and fuel gas ports;
FIGURE 3 is a view, partly in section, of an illustrative embodiment of this invention; and
FIGURES 4 and 5 illustrate variousdevices for securing the porous element in place.
A metal workpiece, shown in FIGURE 1 as a billet 10, travels along a mill table or conveyor in the direction indicated by the arrow in the drawing. Scarfing torch 11 is connected to a suitable torch holder, not shown and is arranged to scarf the top surface of the workpiece. It is generally easier to manipulate the workpiece relative to the tool rather than vice versa. As shown in FIGURE 2 the torch has a large transverse dimension d so that the total transverse area of the workpiece may be scarfed in one pass. The scarfing torch is arranged at an angle to the surface of the workpiece as shown in FIGURE 1. The highly oxidizing stream of gas, consumes and removes the defective surfaces of the billet and thereby puts the surface of the billet in condition for rolling, etc.
The inlet ports for the oxygen and fuel gas in the conventional burner are. shown schematically in FIGURE 1 and more clearly in the sectional representation, FIG- URE 2. The burner nose 13 is made of copper and has a forward face 14 with a slotted portion 12 therein. The slotted portion has a rectangular cross section as shown in FIGURE 2. The inlet ports 16 for the oxygen are located in the rear face 15 of the slotted portion and comprise discrete openings transversely spaced across the nozzle. The. inlet ports are in communication, via conduits 17, with an oxygen manifold 18 which is supplied with oxygen under pressure from any conventional source. The inlet ports are spaced close enough together to form what is in effect a blanket of oxygen directed against the metal surface of the workpiece. The fuel gas inlets 19 are located along the lines of intersection of faces 20 and 21 with rear face 15 and comprise discrete openings transversely spaced across the said lines. The openings are in communication with a fuel gas manifold via conduits 23. The fuel gas manifold may also be located in the rearward portion of the nozzle and may be supplied from any suitable source of fuel gas. The manifold system has not been extensively described in that it forms no real part of the step forward in the art which this application is attempting to cover. A suitable manifold system is described in the United States Letters Patent No. 2,346,718 to I. L. Anderson issued on April 18, 1944.
The system of fuel gas inlet ports illustrated in FIG- URE 2 is defective in at least two respects. Firstly the openings or inlets 19 are discrete, relatively small and are located close to the scarfing action. As a result, spatter from the scarfing action often enters the inlets, hardens and clogs them. The fuel gas is therefore unable to enter the oxygen stream and uneven scarfing results. The second major defect is that the spaced fuel gas inlet ports do not provide for an evenly distributed flow of fuel gas into the oxygen stream.
The embodiment shown in FIGURE 3 was devised in an attempt to alleviate the deficiencies noted above in the conventional scarfing nozzle. The oxygen inlet port system 16, 17 and associated manifold 18 have not been changed. The fuel gas inlet port system has been replaced with an improved system which will now be described.
Channels have been machined in the upper 20 and lower 21 surfaces of the slotted portion. The channels are indi cated generally by reference numerals 26 27 and extend transversely across the scarfing nozzle. Only the structure of the upper fuel gas inlet supply system will now be described in detail, it being understood that the lower system is structurally comparable. The upper portion of the channel 26 is utilized as a fuel gas gallery 28 which is connected to the supply manifold by means of conduits 30. The lower portion of the upper gallery is closed by means of a porous ceramic or metal plate 29. This plate extends the full width of the channel and separates the fuel gas gallery from the slotted portion 12. The plate 29 may be made of a suitable porous ceramic material, mesh screen or compressed mesh. It has been found that a compressed mesh of stainless steel wire is a highly suitable material. The porous material accomplishes two purposes. Firstly it provides a continuous area of openings all the way across the nozzle and is thus less subject to clogging with slag and other foreign matter. Secondly it provides for a more even distribution of fuel gas flow into the transverse length of a more or less continuous sheet of oxygen so as to avoid regions of extreme thermal conditioning in the oxygen stream. The porous material and the pressure in the fuel gas supply system must be selected so that an adequate supply of the fuel gas enters the oxygen blanket.
For best results the porous surface should be of an elongated rectangular configuration although a series of square or circular porous openings might be used. It is, of course, obvious that when the porous surface is interrupted the continuous transverse blending feature is affected.
In operation, oxygen gas is supplied to the oxygen manifold 18 and is transmitted to the slotted portion 12 by conduits 17. At the same time a supply of fuel gas is forced through the conduits 30 into the galleries 28. The fuel gas then completely fills the galleries and proceeds to pass through the porous plate 29 and combine with the oxygen blanket. By utilizing a pair of plates one on either side of the oxygen stream a greater supply of fuel gas may combine therewith in a more uniform manner.
FIGURES 4 and illustrate various means for securing the porous material to the nozzle. In FIGURE 4 metal clips are used to lock the material in place. FIGURE 5 illustrates that the nozzle may be recessed 36 to accept the porous material. In both of the aforementioned views the material may be readily removed and replaced. In FIGURE 3 the material is bonded by suitable means to the nozzle and replacement is relatively more difiicult.
Herctofore, when the gas emitting ports clogged up they had to be redrilled or the nozzle replaced. Now the porous material may be removed and replaced quite easily and as a result the equipment is subject to much less down time.
Any suitable fuel gas may be used in combination with the oxygen blanket. Natural gas is often used due to its abundance, cost and properties.
As mentioned previously the inventive concepts involved in this disclosure may be applied in any instance where fluids are intermixed and it is desired that a complete and uniform intermixing be obtained. The concepts can be applied to other flame cutting tips, commercial heating equipment, various chemical processes etc. The fluids mixed may be either liquids or gases or combinations thereof.
While illustrative forms of apparatus and methods in accordance with the invention have been described and shown herein, it will be understood that numerous changes may be made without departing from the general principles and scope of the invention.
1. A scarfing burner comprising a nozzle having a transversally slotted opening therein for discharging a scarfing gas stream, said slotted opening having rear and side walls, discrete oxygen inlet ports through said rear wall, means to supply oxygen to said inlet ports, fuel gas supply means extending over substantially the entire length of each of said side walls, said side walls comprised in part over substantially their entire length of porous metal means forming a gas passage between said fuel gas supply means and said slot.
References Cited UNITED STATES PATENTS 1,401,404 12/1921 Hoffman 431328 2,346,718 2/1942 Anderson 148-95 2,363,089 11/1944 Scherl 148-95 2,838,431 6/1958 Allmang et a1. l489.5 2,841,213 7/1958 Piolenc et al 431l58 3,084,736 4/1963 Mentel et a1 431329 3,185,461 5/1965 Fugossi 431329 FOREIGN PATENTS 764,446 3/1934 France.
EVERETT W. KIRBY, Primary Examiner US. Cl. X.R.