US3645520A

US3645520A - Consumable lance

Info

Publication number: US3645520A
Application number: US59267A
Authority: US
Inventors: Thomas R Acre; Frederick M Gimbel; Sundaresan Ramachandran; Thomas F Beck
Original assignee: Allegheny Ludlum Industries Inc
Current assignee: Allegheny Ludlum Corp; Pittsburgh National Bank
Priority date: 1970-07-29
Filing date: 1970-07-29
Publication date: 1972-02-29
Anticipated expiration: 1989-02-28
Also published as: JPS5511879B1; FR2099664A1; NL7110431A; FR2099664B1; CA953106A; GB1318486A; NO131137B; AU465187B2; AU3153471A; BE770687A; AT324380B; DE2136743B2; SE375325B; NO131137C; DE2136743A1

Abstract

Described herein is a consumable lance for introducing fluid into a liquid at a controlled angle of introduction as the lance is consumed.

Description

United States Patent Acre et al.

[ 3 Feb.29,i972

CONSUMABLE LANCE inventors: Thomas R. Acre, Lower Burrell; Frederick M. Gimbel, Delmont; Sundaresan Rarnachandran, Natrona Heights; Thomas F. Beck, Bethel Park, all of Pa.

Assignee: Allegheny Ludlum Industries, Inc., Pittsburgh, Pa.

Filed: July 29, 1970 Appl. No.: 59,267

us. Cl ..266/34 L, 239/602 Int. Cl ncz i /pg [58] Field of Search ..239/l32.3, 132.5, 265.15, 602; 266/34 L, 34 LM, 34 T [56] References Cited UNITED STATES PATENTS 2,506,598 5/!950 Johnson ..266/34 T Primary Examiner-Gerald A. Dost Attorney-Richard A. Speer and Vincent G. Gioia [5 7] ABSTRACT Described herein is a consumable lance for introducing fluid into a liquid at a controlled angle of introduction as the lance is consumed.

15 Claims, 3 Drawing Figures Patented Feb. 29, 1972 FIG. 3.

$ 645 FLOW INVENTORS.

SU/VD/JRESA/V RAMA CHANDRA/V and THO/HA5 R. ACRE, FREDERICK M. GIMBEL THOMAS F. BECK 1 AHorney CONSUMABLE LANGE There are many situations in which it is necessary or desira' ble to introduce a fluid into a volume of liquid. In some cases the fluid may be introduced for stirring purposes and, in others, for reaction with the liquid. Within the latter embodiments are those in which a gas, such as oxygen, is introduced into a volume of molten metal, such as iron or iron alloys. Various oxygen steelmaking practices require oxygen or mixtures of gases containing oxygen to be projected onto the surface or within the melt of molten metal. For the most part, lances are utilized which are either refractory protected, water cooled, or both but which basically are merely pipes vertically extended into a furnace containing the molten metal.

A variety of problems may result from the introduction of a fluid into a volume of liquid, particularly at high pressures. One such problem may be splashing of the liquid. Where the liquid is hot, corrosive, or otherwise hazardous to personnel, splashing of the liquid may be a particularly difficult problem. It has been discovered that by controlling the angle of the introduction of the fluid into the liquid, splashing may be minimized and, furthermore, distribution and dispersion of the fluid into the liquid may be enhanced. For the introduction of fluid'into molten metal, such as iron and iron alloys, this angle must be critically controlled within to 90 of the longitudinal axis of the lance for maximum efficiency and minimum splashing. Preferably the angle should be between 25 and 75.

A relatively simple device may be constructed to introduce fluid into a volume of liquid at an angle by simply bending the fluid discharge ends of conduits to the required angle. However, such lances cannot be used effectively in environments in which the lance is consumed since erosion of the lance beyond the angled portion of the conduits will materially reduce the effectiveness of the lance. Although it is possible to employ refractory or other protective coverings which will substantially preclude consumption of the lance as described, another approach is to utilize consumable lances. It is obvious, however, that a problem arises in the use of a consumable lance to maintain the angle of fluid ejection in a controlled fashion throughout the length of the lance as it is consumed. The present invention provides a consumable lance for introducing fluid into a volume of liquid at a controlled angle of introduction as the lance is consumed.

In accordance with the invention there is provided a consumable lance which comprises an exterior housing, at least one continuous conduit through which fluid may be passed disposed within the housing, with the continuous conduit being at a controlled angle, inclined to the longitudinal axis of the lance, substantially throughout the consumable portion of the conduits length. In this manner, as the lance and conduit are consumed, the angle of fluid emergence therefrom is controlled. In lance designs for use in introducing fluid to molten metal such as iron and iron alloys, the angle of fluid emergence of the conduit supplying same, is controlled to 15-90 from the longitudinal axis of the lance throughout the consumable portion of the conduits length.

Lances, in accordance with the invention, may be effectively used in oxygen steel refining, and in particular, in the vacuum decarburization of alloy steels.

The following discussion in combination with the accompanying drawings describe several embodiments of the invention.

In the drawings, FIG. 1 is an elevation view schematically illustrating one embodiment of a consumable fluid injection lance which maintains inclined fluid jets while being consumed, and

FIG. 2 is an illustration of a second embodiment of a consumable fluid injection lance with also maintains controlled angle during consumption of the lance, and

FIG. 3 is an illustration of a third embodiment of lance design but one composed of multiple sections.

As can be seen by the illustrations in FIGS. Ito 3, the con sumable lance comprises an exterior housing 10, NA, and 10B and

various conduits

12, 12A, and 12B, through which fluid may be passed, disposed within the housing. The conduits are continuous, at least through that portion of the lance which is intended to be consumed. The conduits are connected at the fluids entry end thereof to a source of fluid supply, such as a feeder pipe 8, which may be connected to the source by a pipe connector, as shown. Although the exterior housing may be constructed of any suitable material, depending upon the use to which the lance will be subjected, a common housing material for construction would be a protective refractory in lances to be used for injecting fluids into molten metal. Indeed, the entire lance may be constructed of refractory material. The term housing" is used herein in its broadest sense and refers to any covering, or the like, for the conduits through which the fluid may be passed. The conduits, themselves, terminate in

orifice

14, 14A, and 148. When the lance is emersed into a volume of liquid, fluid will be discharged through the conduits into the liquid at an angle inclined tothe longitudinal axis of the lance. In the case of lances for use in injecting fluids into molten metal, this angle should be between 15 and preferably between 25 and 75.

In the embodiment illustrated in FIG. 1, the continuous conduits are spiral. The angle of the spiral is controlled so that as the lance is consumed, fluid will be discharged into the liquid at a predetermined, selected angle. It can also be seen that for optimum results a plurality of conduits are used. This assures effective dispersion and distribution of the fluid within the volume of liquid. Although the spiral form is presently preferred, the conduit configuration shown in FIGS. 2 and 3 may be equally satisfactory. As can be seen in FIG. 2, the conduits zigzag throughout at least the consumable portion of its length in the lance. Together, the zigzagging conduits form a crisscrossing pattern. In the illustration shown in FIG. 3, the conduits zigzag into an X-shaped pattern.

The illustration in FIG. 3 also shows an embodiment in which a plurality of sections may be joined to produce a lance of any desired length. Such a construction may be feasible for mass production of the lance segments with the interchangeability of the segments being an added advantage of this embodiment. The segments together form what is in effect a plurality of continuous conduits throughout the length of at least the consumable portion of the lance.

Extensive testing of various lances has demonstrated that the angle of introduction of the fluid into the liquid has an extremely important effect of dispersion into the liquid and splashing thereof. An inclined gas jet of 15 to 90, from the vertical, provides the requirements of adequate bubble dispersion and minimal splashing effect. Both of these factors are of particular importance in metal refining such as decarburization of iron and iron alloys.

Within the purview of the invention, the lance construction may be adapted to particular applications to optimize operation. Thus, for example, the number and arrangement of orifices, the size of the orifices and conduits, and the flow rates may be selected in accordance with specific requirements. However, once an angle of fluid ejection has been chosen or predetermined, the lance design in accordance with the invention may be effectively utilized to assure a controlled fluid ejection angle throughout the consumable portion of the lance.

We claim:

1. A consumable lance for introducing fluid into a liquid at a controlled angle of introduction as the lance is consumed which comprises an exterior housing, at least one continuous conduit through which fluid may be passed disposed within said housing, said continuous conduit being at a controlled acute angle to the longitudinal axis of said lance substantially throughout the consumable portion of the conduits length such that as the lance and conduit are consumed, the angle of fluid emergence therefrom is controlled.

2. A lance according to claim 1 including a plurality of conduits each at said controlled angle throughout the consumable portion of its length.

3. A lanceaccording to claim I wherein said housing comprises a refractory sheath.

4. A lance according to claim 1 including a spiral having a controlled spiral angle to provide a controlled fluid emergence angle as it is consumed.

5. A lance according to claim 1 including a zigzagging conduit of controlled angles.

6. A lance according to claim 1 including a plurality of spiral conduits of controlled angles.

7. A lance according to claim 1 including a plurality of zigzagging conduits.

8. A lance according to claim 7 wherein said conduits are in a crisscrossing pattern.

9. A lance according to claim 1 including a plurality of conduits in an X-shaped pattern.

10. A lanceaccording to claim 9 wherein said conduits are in a multiple of X-shaped patterns.

11. A consumable lance for introducing fluid into a volume of molten metal at a controlled angle as the lance is consumed to minimize splashing of said metal, which comprises at least one continuous conduit through which fluid may be passed and a protective housing therefor, said continuous conduit ing a fluid from the group consisting of oxygen and oxygencontaining gas into molten iron and iron alloys which includes a plurality of continuous conduits, each at a controlled angle of between to 90 substantially throughout the consumable portion of its length.

13. A consumable lance, according to claim 12 wherein said continuous conduits are spiral.

14. A consumable lance according to claim 12 wherein said conduits zigzag substantially throughout the consumable portion of their lengths and form a crisscrossing pattern.

15. A consumable lance according to claim 12 including X'- shaped conduits.

A UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3, 645, 52.0 Dated February 29, 1972 Thomas R. Acre, Frederick M. Gimbel, lnventofls) Sundaresan Ramachandran and Thomas F. Beck It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

In claim 11, column 4, line 3, delete the word "circuit" which appears before conduit 5 length".

Signed and sealed this 16th day of July 197A.

(SEAL) Attest:

McCOY M. GIBSON, JR. 0. MARSHALL DANN Attesting Officer Commissioner of Patents FORM po'wso uscoMM-oc 60376-P59 U.S. GOVERNMENT PRINTING lDFFICE I969 o-ass-au.

Claims

1. A consumable lance for introducing fluid into a liquid at a controlled angle of introduction as the lance is consumed which comprises an exterior housing, at least one continuous conduit through which fluid may be passed disposed within said housing, said continuous conduit being at a controlled acute angle to the longitudinal axis of said lance substantially throughout the consumable portion of the conduit''s length such that as the lance and conduit are consumed, the angle of fluid emergence therefrom is controlled.

3. A lance according to claim 1 wherein said housing comprises a refractory sheath.

7. A lance according to claim 1 including a plurality of zigzagging conduits.

10. A lance according to claim 9 wherein said conduits are in a multiple of X-shaped patterns.

11. A consumable lance for introducing fluid into a volume of molten metal at a controlled angle as the lance is consumed to minimize splashing of said metal, which comprises at least one continuous conduit through which fluid may be passed and a protective housing therefor, said continuous conduit being at a controlled angle of between 15* and 90* to the longitudinal axis of said lance substantially throughout the consumable portion of the circuit conduit''s length such that as the lance and conduit are consumed, the angle of fluid emergence therefrom is controlled.

12. A consumable lance according to claim 11 for introducing a fluid from the group consisting of oxygen and oxygen-containing gas into molten iron and iron alloys which includes a plurality of continuous conduits, each at a controlled angle of between 15* to 90* substantially throughout the consumable portion of its length.

15. A consumable lance according to claim 12 including X-shaped conduits.