US3433472A - Apparatus for controlling flow of liquid from a container - Google Patents

Description

3,433,472 APPARATUS FOR CONTROLLING FLOW 0F LIQUID FROM A CONTAINER Filed Oct. 22, 1965 March 18. 1969 Yl-CHUNG CHANG ETAL Sheet g ofz flab/e Ferro Stat/e Level Ind/color 1G: 3-

Amplifier INVENTORS. Yl- CHUNG CHANG and HENDR/K COL/JN By Attorney United States Patent 3,433,472 APPARATUS FOR CONTROLLING FLOW OF LIQUID FROM A CONTAINER Yi-Chung Chang, Franklin Township, Westmoreland County, and Hendrik Colijn, Monroeville Borough, Pa.,

assignors to United States Steel Corporation, a corporation of Delaware Filed Oct. 22, 1965, Ser. No. 501,346

US. Cl. 26638 Int. Cl. C21b 7 /14; F27d 3/00 5 Claims ABSTRACT OF THE DISCLOSURE This invention relates to apparatus for controlling flow of liquid from a container and more particularly for controlling molten pig iron from a blast furnace. At present the molten iron is withdrawn intermittently from the blast furnace at intervals of several hours. However, there are advantages of continuously discharging the pig iron. For example, it is possible to maintain the level of the molten iron within a relatively narrow range which permits better operation of the furnace. Since the smelting rate varies considerably this requires that the rate of metal discharge be varied.

It is therefore an object of the present invention to pro- -vide apparatus for controlling fiow of fluid from a container in which the rate of discharge must be varied.

Another object is to provide apparatus for continuously discharging molten metal from a blast furnace and for varying the rate of the discharge to maintain a predetermined iron level in the furnace.

These and other objects will be more apparent after referring to the following specification and attached drawings, in which:

FIGURE 1 is a sectional view of the apparatus of our invention installed on a blast furnace;

FIGURE 2 is an end view of the apparatus of FIGURE 1; and

FIGURE 3 is a schematic wiring diagram of a control which may be used with our invention.

Referring more particularly to the drawings, reference numeral 2 indicates the hearth portion of a blast furnace having a conventional 'bustle pipe 4, tuyere 6 and tapping hole 8. A collar 10, attached to the furnace, surrounds the tapping hole 8. The collar 10 has a lining 12 of refractory material, such as fireclay, with an axial opening 14 therethrough aligned with tapping hole 8. A member 16 having an inwardly extending radial flange 17 thereon is attached to the outer end of collar 10. A flow control member 18 is rotatably secured to the collar 10. The member 18 includes a swing nozzle 20 having an outwardly extending radial flange 22 at one end which is received within the member 16 so that a rotatable joint is provided between the swing nozzle 20 and collar 10. The swing nozzle 20 is of inverted generally S-shape with the end opposite the collar 10 joined to a similarly shaped receiver 24 through a flanged connecting section 26 which is provided with an air vent 28. As shown, nozzle 20 is formed of two ninety degree elbows 20A and 20B and 3,433,472 Patented Mar. 18, 1969 receiver 24 is formed of two ninety degree elbows 24A and 2413. The members 20, 24, and 26 are provided with refractory linings 30, 32, and 34 providing passageways 36, 38, and which are connected to opening 14. It will be seen that the combined passageways have a portion aligned with the opening 14 and a portion offset therefrom. The entry end of the nozzle 20 and the discharge end of the receiver 24 are preferably in the same horizontal plane. However, the receiver 24 merely serves to direct the molten iron to the desired discharge point so that it can be omitted in some installations. Electrical heating coils 42 are preferably provided in the casing of receiver 24 and connector 26. A shaft 44 rotatably mounted in bearings 46 has its ends secured to nozzle 20 and receiver 24. A gear 48 secured to shaft 44 is in mesh with a pinion 50 secured to a shaft 52 for rotation therewith. A reversible DC. motor 54 is connected to shaft 52. A counterweight 56 may be connected to connector 26 by means of wire rope 58. A level indicator 60 is provided in the furnace to provide an indication of the position of interface F between the molten iron M and the slag S. The level indicator may be of any standard type, but is preferably that described in Chang application, Ser. No. 489,914, filed Sept. 24, 1965, and entitled Method and Apparatus for Locating Interfaces Between Fluids. A level indicator as shown in Milness Patent No. 3,204,460, dated Sept. 7, 1965, may also be used. A level indicator 62, similar to indicator 60, may be provided to indicate the slag level.

-In operation, fluid head H provided in the nozzle 20 supplies pressure equal to or slightly less than the maximum outlet pressure at the tapping hole 8 when positioned vertically as shown in FIGURES 1 and 2. The molten iron is discharged from receiver 24 continuously. If the iron level, as indicated by indicator 60, rises above that desired the workman operates the motor 54 in a direction which will rotate the nozzle 20 toward a horizontal position so as to decrease the resistance to metal flow provided by the head H. As a result the rate of flow of the iron from the furnace will increase to reduce the iron level to that desired. If the iron level becomes lower than that desired, as indicated by the level indicator 60, the motor 54 will be operated in a direction to rotate the nozzle 20 toward a vertical position and thus lower the rate of flow of metal from the furnace. The air vent 28 insures that the pressure in the receiver 24 does not fall below atmospheric pressure to cause siphoning of the metal into the reciver. Thus, the effective head H is always the distance between the axis of opening 14 and the axis of passageway 40. If necessary, power may be applied to the heating coils 42 to keep the molten iron fluid to insure its flow through passageways 14, 36, 38, and 40.

It will be understood that an identical nozzle and receiver combination may be provided for discharging the slag from the furnace through the cinder notch. In this case the operating motor will be actuated in accordance with the reading of the level indicator 62.

By utilizing the apparatus of FIGURE 3, the rate of discharge of molten iron may be controlled automatically. As there shown, a bridge circuit consisting of a DC. power source and adjustable resistors 72, 74, and 76 are connected to an amplifier 78. Arm 72A is connected through coil to resistor 76, arm 76A and arm 74A to resistor 74. The output of amplifier 78, which is proportional to the current in coil 80, is connected to generator field 82F of a generator 82. The output of generator 82 is connected to DC motor 54 which has constant field excitation by means of field 54F. A motor 84, which is either part of the level indicator 60 or is movable in response to a signal from the indicator 60; is mechanically connected to arm 74A. A similar circuit may be used in conjunction with indicator 62 to control slag discharge.

In operation, arm 72A is set at the desired position so as to provide a set point for the desired level to be maintained in the molten iron. Arm 74A is actuated by motor 84 in response to a signal from the level indicator 60. If the level of the molten iron is within the desired range the system will be in balance and the motor 54 will remain stationary. When the molten iron level becomes lower than that desired, direct current will flow in a direction to cause the motor 54 to rotate in the direction which will move the nozzle 20 toward a vertical position. When the level of the molten iron rises above that desired, as determined by arm 72A, direct current will flow in the opposite direction so that the motor 54 will cause the nozzle 20 to rotate toward a horizontal position.

While two embodiments of our invention have been shown and described, it will be apparent that other adaptations and modifications may be made without departing from the scope of the following claims.

We claim:

1. Apparatus for maintaining and controlling the rate of continuous flow of liquid from a container, liquid being added to said container as it is withdrawn, said container having a discharge opening therein for said liquid; said apparatus comprising a flow control member having an entry end and a discharge end with an opening extending therethrough from entry end to discharge end; connecting means rotatably supporting said flow control member with the opening in its entry end aligned with said discharge opening; the opening in said flow control member having a portion offset with respect to and at a higher elevation than said discharge opening; a vent from the opening in said last named portion to the atmosphere to prevent siphoning of the liquid; means for rotating said flow control member about the axis of its entry end to change the elevation of said offset portion so as to provide a pressure head of liquid in said flow control member approximately equal to the pressure at the discharge opening; said rotating means including a rotatable shaft connected to said flow control member, a motor, and means connecting said motor to said shaft to rotate the same; an indicator for indicating the level of the liquid in said container, and means operable by said liquid level indicator for operating said motor to rotate said flow control member to a more upright position when the liquid level falls below a predetermined elevation and to rotate said flow control member to a less upright position when the liquid level is above a predetermined elevation.

2. Apparatus according to claim 1 in which said flow control member includes a ninety degree elbow at its entry end which faces upwardly when the flow control member is upright, a second ninety degree elbow connected to said first elbow with its remote end extending upwardly away from said entry end, a third ninety degree elbow connected to said second elbow with its remote end extending downwardly, and a fourth ninety degree elbow connected to said third elbow with its remote end extending downwardly and away from said discharge opening; and said connecting means includes a collar surrounding said discharge opening and having an axial hole therethrough; a member having an inwardly extending radial flange thereon attached to said collar, and an outwardly extending radial flange on said first elbow received between said collar and said radial flange of said member.

3. Apparatus for controlling flow of molten iron from a blast furnace having a discharge opening for tapping molten iron which comprises a flow control member having an entry end and a discharge end with an opening extending therethrough from entry end to discharge end, connecting means rotatably suporting said flow control member with the opening in its entry end aligned with said discharge opening, the opening in said flow control member having a portion offset with respect to said discharge opening, a vent from said last named portion to the atmosphere, and means for rotating said flow control member about the axis of its entry end to change the elevation of said offset portion.

4. Apparatus according to claim 3 in which said rotating means includes a rotatable shaft connected to said flow control member, a motor, and means connecting said motor to said shaft to rotate the same.

5. Apparatus according to claim 4 including an indicator for indicating the level of the iron in said furnace, and means operable by said level indicator for operating said motor to rotate said flow control member to a more upright position when the iron level falls below a predetermined elevation and to rotate said flow control member to a less upright position when the liquid level is above a predetermined elevation.

References Cited UNITED STATES PATENTS 578,708 3/1897 Baldwin l37579 X 2,549,790 4/1951 Finkeldey et al 26638 2,568,578 9/1951 Bennett 26638 X 2,652,854 9/1953 Stoddard l37577 2,656,925 10/ 1953 Johnson 137-579 X 3,204,460 9/ 1965 Milnes 73295 J. SPENCER OVERHOLSER, Primary Examiner.

E. MAR, Assistant Examiner.

US. Cl. X.R. 137579

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