US3334885A - Oxygen lance with continuous wide angle conical oxygen jet - Google Patents

Description

C. R. TAYLOR Aug. 8, 1967 OXYGEN LANCE WITH CONTINUOUS WIDE ANGLE CONICAL OXYGEN JET Filed Nov. l2, 1964 mm f WDA.

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United States Patent C) 3,334,885 GXYGEN LANCE WITH CONTINUOUS WIDE ANGLE CONICAL OXYGEN JET Charles R. Taylor, Trenton, Ohio, assignor to Armco Steel Corporation, Middletown, Ohio, a corporation of Ohio Filed Nov. 12, 1964, Ser. No. 410,673 6 Claims. (Cl. 266-35) ABSTRACT F THE DISCLOSURE An oxygen lance comprising an elongated tubular nozzle terminating in a nose having a continuous annulardischarge orifice which is downwardly and outwardly inclined so as to discharge oxygen therefrom in a continuous concial stream, the lance embodying means for delivering oxygen to the nose thereof for discharge through the discharge orifice and conduit means in communication with a hollow chamber in the nose of the lance for circulating a coolant therethrough.

This invention relates to the provision of a lance by means of which oxygen may be injected into an open hearth furnace or a converter type vessel wherein a charge of molten iron is converted into steel by directing a stream of oxygen downwardly onto the charge. The invention has to do more particularly with an improved nozzle construction embodying a continuous wide angle oxygen jet.

Oxygen lances heretofore employed in the oxygen converter method of steel making have been found objectionable in that they have provided a localized highenergyimpingement of oxygen on the surface of the molten charge. Such high-energy impingement, whether it be from a single outlet orifice in the nose of the lance or from a plurality of spaced apart orifices, creates localized areas ofI turbulence on the surface of the charge resulting in undesirable splashing or washing of the molten metal. This not only reduces the efficiency of the operation but additionally causes the lance to become incrusted with splashes of metal which reduce the efficiency of the lance as well as materially reduce its useful life.

In accordance with the instant invention, it has been found that the oxygen can be more efficiently injected into the molten metal by `discharging it from a single annular jet or orifice disposed so as to direct the oxygen downwardly and outwardly at a relatively wide angle, thereby causing the oxygen to contact the surface of the charge over a wide contact area. Thus, instead of the oxygen being directed onto the surface of the bath in the form of one or more individual streams having limited .contact area, the oxygen contacts the surface of the molten charge in a continuous conical stream which provides a significantly larger reaction area than that obtained by the use of one or more individual streams. In effect, the bath is contacted by a ring of oxygen which may be of substantial diameter, the diameter of the stream depending upon the angle of inclination of the annular outlet orifice and the distance between the nose of the lance and the surface of the charge. The oxygen thus impinges on the surface of the charge in an annular area spaced radially outwardly from the nozzle of the lance where there is less likelihood of splashes of molten metal striking and sticking to the lance.

In accordance with the foregoing, it is a principal object of the instant invention to provide an oxygen lance having alcontinuous wide angle oxygen jet which permits high volume oxygen flow without excessive splashing or washing when used as a'n open hearth roof lance.

A further object of the invention is the provision of 3,334,885 Patented Aug. 8, 1967 ICC a lance structure having a single conical discharge orifice the angle of which may vary from the vertical up to nearly so as to discharge oxygen therefrom in a continuous wide range conical stream.

Still a further object -of the invention is the provision of an oxygen lance of the character described consisting of a plurality of concentric tubes arranged to provide a water-cooled barrel or nozzle and a water-cooled tip or nose, the latter being formed in two parts so shaped and spaced relative to each other as to provide an annular Space between them which serves as the oxygen orifice, the annular space comprising a section of a wide angle cone.

The foregoing objectives, together with others which will appear hereinafter or which will be apparent to the skilled worker in the art upon reading this specification, are accomplished by that construction and arrangement of parts of which an exemplary embodiment will now be described.

Reference is made to the accompanying drawing where- FIGURE l is a side elevational view of a lance constructed in accordance with the invention.

FIGURE 2 is an enlarged vertical sectional view illustrating the nose of the lance together with the lowermost ends of concentric tubes through which oxygen and water are caused to flow.

Referring first to FIGURE l of the drawings, the lance comprises a head or body 1 having an elongated tubular barrel or nozzle 2 having a lower portion 2a which terminates at its lowermost end in a tip or nose 3. The lance structure is adapted to lbe suspended within a furnace or converter by means of a removable eye ring 4 threaded into the upper end of the body.

In the embodiment illustrated the body or head of the lance is composed of a plurality of body sections 5, 6, 7, 8, and 9 each having a chamber communicating with one of the concentric tubes making up the lance nozzle. In the exemplary arrangement illustrated, the body sections 5 and 8 are adapted to introduce water into the lance through conduits 10 and 11, respectively; whereas the body sections 6 and 9 serve to discharge the water after it has been circulated through the lance, the water being discharged through conduits 12 and 13. In similar fashion, body section 7 receives oxygen through conduit 14 for delivery to the nose of the lance where it is discharged through annular orifice 15.

The annular orifice 15 discharges the oxygen in the form of a wide angle cone, indicated at 16, which is caused to impinge upon the surface 17 of the molten metal in the form of an annular ring 18 which is essentially radially disposed with respect to the nose of the lance.

Referring now to FIGURE 2, it will be seen that the elongated tubular nozzle 2 comprises the outermost tube of a series of concentric tubes 19, 20, 21 and 22 which define annular passageways 23, 24, 25 and 26, together with centrally disposed passageway 27.

At their lowermost ends the concentric tubes are received by the nose member 3 which, in the embodiment illustrated, is composed of a ring-like inner part 28 and a hollow bulb-like outer part 29 which, when joined to the inner part, lies in spaced relation to the undersurface of the inner part, the two parts defining the annular orifice 15 therebetween.

The ring-like inner part 28 has an annular channel 30 the outer wall 31 of which is secured to the lowermost end of the elongated tubular nozzle 2. Its inner wall 32 is secured to the lowermost end of concentric tube 20; and the intermediate concentric tube 19 terminates short of the bottom of the annular channel 30, thereby effectively connecting passageways 23 and 24 at their lowermost ends.

At its uppermost end the tube 19 communicates with the hollow interior of body section 8, whereas the uppermost end of passage 23 communicates with the interior of body section 9. Thus, a coolant, usually water, may be introduced into one of the aforementioned body sections, such as the section 8, and caused to ow downwardly through annular passageway 24 and thence upwardly through annular passageway 23 for discharge through body section 9 and conduit 13. The coolant thus serves to cool the lance structure, particularly the elongated tubular nozzle 2.

The bulb-like outer part 29 has an upwardly projecting neck 33 which is secured to the lowermost end of tube 21 and hence is suspended therefrom, the bulb-like outer part defining a nose chamber 34 in which an annular bafiie 35 is mounted, the bafiie having an upwardly projecting neck 36 secured to the lowermost end of the innermost tube 22. The baie has a centrally disposed opening 37 therein which lies in prolongation of passage 27. At its uppermost end the passageway 27 will be in communication with the hollow interior of body section 5, whereas passageway 26 will be in communication with body section 6 so that water or other coolant may be circulated through passageways 26 and 27, the coolant preferably flowing downwardly through passageway 27 and opening 37 into nose chamber 34 where it fiows outwardly around bafe 35 and is returned for discharge through passageway 26.

The remaining passageway in the lance, namely passageway 25, is in communication at its lowermost end with the annular orifice and at its upper end with the interior of body section 7. Oxygen may be introduced into the body section 7 through conduit 14 and will flow downwardly through passageway 25 for discharge through the annular orifice 15.

As will be evident, the spacing of the inner and outer parts of the nose relative to each other is such that the annular orifice 15 will be defined therebetween; and to this end, the angle of inclination of the conical stream of oxygen discharged through the nozzle will be determined by the angularity of the undersurface 38 of the inner part 28 and the coacting annular surface 39 of the outer part. Preferably, the surfaces 38 and 39 converge outwardly in the manner illustrated, with the flow-controlling constriction at the annular orifice 15. The centerline of the converging surfaces, which is indicated at A, defines the discharge path of the oxygen, as also illustrated at 16 in FIGURE l. Such arrangement assures the uniform discharge of oxygen around the periphery of the nozzle and provides a fiow pattern which will not divide into separate channels upon discharge from the orifice. In an exemplary embodiment, the centerline A is disposed at an angle of 221/2 from the horizontal. The angle of inclination may be varied depending upon how close to the surface of the molten charge the lance is to be used, its discharged diameter, and the desired configuration of the eii'luent oxygen. The angle thus may vary from but a few degrees from the horizontal to substantially in excess of the 221/2 figure of the exemplary embodiment.

It will be understood that suitable supporting webs or spider members, such as the members 40, 41 and 42 will be interposed between the concentric tubes and/or the parts making up the nose in order to maintain the various parts in proper spaced relationship. In order to assure a continuous and uniform conical stream, the members 41 should not project into the space defined by the surfaces 38 and 39. It is preferred that the portions of the lance structure which might be subject to attack by molten metal, such as the nose 3 and the lower portion 2a of barrel 2, be constructed from OFHC copper (oxygen-free high conductivity), or other similar high quality and high conductivity material to insure optimum heat transfer properties.

Modifications may be made in the invention without departing from its spirit and purpose. For example, a single water cooling system could be employed for the passageways 23, 24 and 26, 27, the passageways being interconnected so as to assure that the tip 3 and barrel 2 receive adequate quantities of coolant.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. An oxygen lance having an elongated tubular nozzle terminating at its free end in a nose, a single continuous annular discharge orifice at the nose end of said lance defined by opposing surfaces lying in spaced apart relation to define said continuous annular orifice therebetween, means within said nozzle structure for delivering oxygen to said nose for discharge through said discharge orifice, said discharge orifice being outwardly and downwardly inclined so as to discharge oxygen therefrom in a continuous conical stream, said nose in part at least lying beyond said annular orifice and being of hollow construction to define a chamber therein, and conduit means within said nozzle and in communication with the chamber in said nose for circulating a coolant therethrough.

2. An oxygen lance having an elongated tubular nozzle terminating at its free end in a nose, said nose having a single continuous discharge orifice therein, means within said nozzle for delivering oxygen to said nose through said discharge orifice, said nose comprising an inner part and an outer part, said parts having opposing surfaces lying in spaced apart relation to define said discharge orifice, said discharge orifice being outwardly and downwardly inclined so as to discharge oxygen therefrom in a continuous conical stream, the outer part of said nose being of hollow construction defining a chamber therein, and conduit means within said nozzle structure for delivering a coolant to said outer parts.

3. The lance structure claimed in claim 2, wherein said nose chamber has an annular bafiie therein the periphery of which is spaced inwardly from the wall surfaces of said chamber, wherein said bafiie has a centrally disposed opening therein in communication with said conduit means, whereby coolant introduced into said charnber through said conduit means will be caused to fiow outwardly around said baffle, and wherein an additional conduit means is provided to discharge coolant from said chamber upon passage around said bafiie.

4. The lance structure claimed in claim 3 including other conduit means within said elongated tubular body for circulating a coolant along the inside wall surfaces of said tubular nozzle.

5. An oxygen lance having a plurality of fiuid delivery chambers at one end and an elongated nozzle depending therefrom terminating at its lowermost free end in a nose member, said nose member having a single continuous discharge orifice formed therein extending completely around the periphery of said nose member, means within said nozzle structure for delivering oxygen to said nose member for discharge through said discharge orifice, said discharge orifice being outwardly and downwardly inclined so as to discharge oxygen therefrom in a continuous conical stream.

6. The lance structure claimed in claim 5 including a plurality of concentric tubes arranged within said elongated nozzle in spaced apart relation, one of said tubes having its lowermost end in communication with said discharge orifice and constituting the means for delivering oxygen thereto, the remainder of said concentric tubes being arranged to circulate coolant to said nose member and the wall surfaces of said elongated tubular nozzle.

References Cited UNITED STATES PATENTS 1,466,291 8/1923 Beeby 239-506 X 3,043,577 7/1962 Berry 266--34 3,170,016 2/1965 Grace 266-41 X I. SPENCER OVERHOLSER, Primary Examiner.

E. MAR, Assistant Examiner.

Claims (1)

1. AN OXYGEN LANCE HAVING AN ELONGATED TUBULAR NOZZLE TERMINATING AT ITS FREE END IN A NOSE, A SINGLE CONTINUOUS ANNULAR DISCHARGE ORFICE AT THE NOSE END OF SAID LANCE DEFINED BY OPPOSING SURFACES LYING IN SPACED APART RELATION TO DEFINE SAID CONTINUOUS ANNULAR ORIFICE THEREBETWEEN, MEANS WITHIN SAID NOZZLE STRUCTURE FOR DELIVERING OXYGEN TO SAID NOSE FOR DISCHARGE THROUGH SAID DISCHARGE ORIFICE, SAID DISCHARGE ORIFICE BEING OUTWARDLY AND DOWNWARDLY INCLINED SO AS TO DISCHARGE OXYGEN THEREFROM IN A CONTINUOUS CONICAL STRAM, SAID NOSE IN PART AT LEAST LYING BEYOND SAID ANNULAR ORIFICE AND BEING OF HOLLOW CONSTRUCTION TO DEFINE A CHAMBER THEREIN, AND CONDUIT MEANS WITHIN SAID NOZZLE AND IN COMMUNICATION WITH THE CHAMBER IN SAID NOSE FOR CIRCULATING A COOLANT THERETHROUGH.

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