JPH07280460A - Oxygen blowing apparatus for electric furnace - Google Patents

Abstract

PURPOSE:To prevent damage of a lance body due to reaction, impact force effected at an end of a lance, deformation of a tilting arm by providing a tiling unit having a hydraulic cylinder for moving an oxygen lance at an arbitrary position in an operating port and a buffer at a tilting rod of the oxygen lance. CONSTITUTION:An end of a lance body 3 can be oscillated from a left end to a right end of an operating port 2 substantially horizontally to an angle theta1 by a tilting hydraulic cylinder 6 so provided as to increase an arriving range of oxygen jet injected from an end nozzle of the body 3 at a scrap 12 and to reduce unmelted residue of the scrap 12. A force of the cylinder 6 at a pulling side is transmitted to an end ring 20 via a buffer spring 7-1 disposed between an end fitting 14 and the ring 20, and a force transmitted to the ring 20 is further transmitted to the fitting 14 through a ring 17.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oxygen or oxygen-containing gas blowing device for an electric furnace used for melting metal materials such as scrap and refining molten metal.

[0002]

2. Description of the Related Art As an electric furnace used for melting metal materials, refining molten metal, etc., it is attached to electrodes placed above the metal materials charged in the furnace and furnace walls such as the bottom and side walls of the furnace. A direct current electric furnace that melts metal materials and smelts molten metal by passing an electric current between the electrodes, and an electric current that flows between three electrodes placed above the metallic materials charged in the furnace. An alternating current electric furnace for melting materials and refining molten metal is known.
In this type of electric furnace, in order to promote the melting of metal materials and the refining of molten metal, it is common practice to blow oxygen into the molten metal in the furnace using a consumable pipe.

Conventionally, the oxygen has been blown into the furnace by a worker holding a consumable pipe or setting it on a holding machine, but in recent years, it has been changed from a consumable pipe blowing system. , For example, JP-A 1-21
The method of using a non-consumable water-cooled lance in which the upper blowing lance of the converter shown in Japanese Patent No. 9116 is applied to an electric furnace does not require a worker to connect a new pipe due to exhaustion of the pipe in front of the electric furnace. Therefore, it is adopted as a method that relieves the worker from the work of heavy muscles and high temperature environment.

FIG. 6 is an overall view of a water-cooling lance type oxygen blowing apparatus installed in front of an electric furnace, which was filed previously by the applicants as Japanese Patent Application No. 5-249724 in order to solve the above problems. FIG. 3 is a plan view showing an operating range of the lance body 3 in this device. The lance body 3 is provided at the tip of the arm 4. When the oxygen is blown into the electric furnace, the arm 4 is swung from the retracted position to the blowing position by the swivel device 5 so that the tip of the lance body 3 is at the electric furnace working port. Move to the center of 2.

Further, the arm 4 is provided so that the reach of the oxygen jet flow ejected from the tip nozzle of the lance body 3 to the scrap can be expanded and the unmelted residue of the scrap can be reduced.
By the swinging hydraulic cylinder 6 beside the
The tip of the lance body 3 can be swung in a substantially horizontal direction from the left end to the right end of the working port 2 by an angle (θ1). The positional relationship of the lance body 3 at that time is as shown in 3-2 and 3-3, respectively. become.

[0006]

The above oxygen blowing device has the following problems. 1) a) Since oxygen is blown at a high speed, the molten metal or slag on the front surface of the oxygen jet is scattered inside the electric furnace and the work mouth side, and the scattered molten metal and slag are the tip of the lance inserted into the furnace and the work. If it adheres to the mouth end, continues to grow, and is left untouched, the gap with the end of the work mouth cannot be secured, and the tip of the lance may interfere with the work mouth. b) During scrap cutting, at the time of shifting from the time of cutting to the refining period, there is a possibility that rebound scraps from the furnace and scraps that remain unmelted will collide with the lance tip from the side surface inside the electric furnace. The lance body is likely to be damaged by the lateral reaction force received in the item a) and the impact load in the item b), and the swing arm may be deformed depending on the impact force.

2) In order to secure a clearance for preventing the above item a) c) The state of adhesion of the molten metal and slag adhering to the tip of the lance is visually confirmed after the operation, and depending on the situation, the adhering molten metal and slag Need to be removed manually. d) Since the lance cannot be shaken to both ends of the work port, the reach of the oxygen jet stream to the scrap on the side face of the work port is narrowed, and the cutting and melting time of the scrap becomes long,
This will lead to deterioration of power consumption and oxygen consumption.

An object of the present invention is to prevent the reaction of the tip of the lance, the damage of the lance itself due to the impact force, and the deformation of the swing arm. Another object of the present invention is to provide an oxygen blowing device capable of reducing the work of removing the molten metal and slag adhering to the tip of the lance and expanding the reach of the oxygen jet stream to the scrap.

[0009]

According to the present invention, there is provided an oxygen or oxygen-containing gas comprising an arm for holding an oxygen lance and a swivel device for swiveling the oxygen lance from a retracted position to an oxygen blowing position of an electric furnace working port. In the blowing oxygen blowing device, a swinging device having a hydraulic cylinder for moving the oxygen lance to an arbitrary position in the working opening is provided, and a shock absorber is provided at a swinging rod of the oxygen lance. , Solved the problem.

[0010]

According to the present invention, in a water-cooled lance type oxygen blowing device, an arm for holding the oxygen lance and a turning device for turning the oxygen lance from the retracted position to the oxygen blowing position of the electric furnace, and the oxygen lance as a working port. By providing a swinging device that can be moved from the left end to the right end,
It is possible to relieve the operator from the heavy muscles in front of the electric furnace and the work of high temperature environment, and further it is possible to reduce the unreached range of the oxygen jet in the electric furnace.

By providing a shock absorber on the swing rod of the oxygen lance, 1) lateral reaction force when the lance tip interferes with the working port during swing of the lance, and rebound scrap from inside the furnace, melting The impact force generated when the remaining scrap collides with the tip of the lance can be absorbed by the expansion / contraction mechanism provided in the lance swing device, and the lance body, the lance holder, and the swing arm can be protected. Become.

2) The impact can be absorbed by the expansion / contraction mechanism in the lance swinging device, and it is not necessary to secure a gap between the tip of the lance and the end of the working port. As a result, a) the frequency of manually confirming the molten metal adhering to the tip of the lance and the slag adhering state and manually removing the adhering molten metal and slag is reduced. b) Since the lance body can be shaken to both ends of the work opening, the reach of the oxygen jet to the scrap on the side surface of the work opening can be expanded, and the reach of the oxygen jet to the scrap can be expanded. It is possible to reduce unmelted scrap.

[0013]

Embodiments of the present invention will now be described in detail with reference to the accompanying drawings. FIG. 1 is an overall view of an oxygen blowing apparatus for an electric furnace of the present invention installed in front of an electric furnace, and a plan view showing an operating range of a lance body 3 in this apparatus.

The lance body 3 is provided at the tip of the arm 4, and the arm 4 is blown from the standby position 15 to the blowing position 1 by the turning mechanism 5 when oxygen is blown into the electric furnace.
6 and moves so that the tip of the lance body 3 comes to the center of the electric furnace working port 2. Further, by using the swing hydraulic cylinder 6 provided beside the arm 4, the range of the oxygen jet ejected from the tip nozzle of the lance body 3 to the scrap 12 can be expanded and the unmelted residue of the scrap 12 can be reduced. The tip portion of the lance body 3 can be swung in a substantially horizontal direction from the left end to the right end of the working port 2 by an angle (θ1). The positional relationship of the lance body 3 at that time is as indicated by 3-2 and 3-3, respectively.

FIG. 2 shows a shock absorbing spring 7 attached to the lance swing rod.
It is a block diagram of the impact device provided with -1, 7-2. The lance swinging device includes cushioning springs 7-1 and 7-2 at the tip of the swinging hydraulic cylinder 6 attached to the fixed bracket 10.
And is connected to the swing arm 8 at the rear of the lance body 3 via the swing rod 11. By moving the swinging hydraulic cylinder 6 in and out, the lance body 3 can be swung from the left end to the right end of the working port 2.

FIG. 3 is a partially enlarged view of the lance body 3 shaken to the left end of the working opening 2 in a normal state. The end of the working opening 2 and the lance body 3 are attached with molten metal, slag 9 or the like. There is a gap L (about 200 mm) for preventing interference due to.

FIG. 5 is a partially enlarged view of the shock absorber provided on the swing rod. In normal swinging, the pushing and pulling force of the swinging hydraulic cylinder 6 is performed as follows via the shock absorber. The pulling force of the swing hydraulic cylinder 6 is transmitted to the tip ring 20 via the buffer spring 7-1 between the tip fitting 14 and the tip ring 20, and the force transmitted to the tip ring 20 is applied to the tension rod 13. Further, it is transmitted to the tip fitting 14 via the ring 17.

The force on the push side of the swing hydraulic cylinder 6 is
It is transmitted to the tip fitting 14 via a buffer spring 7-2 between the tip fitting 14 and the ring 17. The buffer spring 7-1 is the normal pulling side force of the swing hydraulic cylinder 6 (the operating force for swinging the lance body 3), and the buffer spring 7-2 is the normal pushing side force of the swing hydraulic cylinder 6. It is composed of a spring constant that does not cause a displacement with respect to the (operating force for swinging the lance body 3). [Balance of Force of Normal Lance Swing Device] Tensile strength of swing rod 11> Force of buffer spring 7-1 ≧
Force of the swinging hydraulic cylinder 6 on the pulling side (operating force for swinging the lance body 3) Compressive strength of the swinging rod 11> Force of the buffer spring 7-2 ≧ Pushing side force of the swinging hydraulic cylinder 6 ( Actuation force for swinging the lance body 3)

FIG. 4 is a state diagram when molten metal, slag 9 and the like adhere to the periphery of the lance body 3 and the working port 2 and the tip of the lance body 3 interferes with the working port 2. The tip of the lance body 3 is in such a state that the gap L1 disappears,
Molten metal around work mouth 2, slag 9 and scrap 12
Interfere with. Further, in some cases, the scrap 12 may fall into the lance body 3. In this case, the reaction force and impact force in the horizontal direction are transmitted through the swing arm 8 and the swing rod 11 at the rear portion of the lance body 3, and the buffer springs 7-1 and 7-2 attached to the tip of the swing hydraulic cylinder 6. Will join.

In order to absorb the horizontal force and impact generated on the pulling side of the swing hydraulic cylinder 6, the swing rod 1
1. A tension rod 13 is provided on the circumference of a ring 17 fixed to the tip, and a pulling force is transmitted to the tip ring 20 via the tension rod 13.

The pulling force is the tip ring 20 and the tip fitting 1.
4, the buffer spring 7-1 is acted on the compression side, and the buffer spring 7-1 is displaced. When absorbing the horizontal force and impact generated on the compression side of the swing hydraulic cylinder 6, the buffer spring 7-2 between the ring 17 and the tip fitting 14 is displaced on the compression side. [Balance of horizontal force and force of lance swinging device when shocked] Tensile strength of swinging rod 11> Force of buffer spring 7-1 <
Force of the swinging hydraulic cylinder 6 on the pulling side (relief pressure of the swinging hydraulic cylinder 6) Compressive strength of the swinging rod 11> Force of the buffer spring 7-2 <Force on the pushing side of the swinging hydraulic cylinder 6 (Swinging hydraulic pressure Cylinder 6 relief pressure)

A buffer spring 7 when a horizontal force or shock is applied
In order to absorb the axial displacement of 1 and 7-2, a guide hole 18 is provided on the side of the swing rod 11 so that the tip of the swing rod 11 and the end fitting 14 can move in the axial direction. The guide shaft 19 of the tip fitting 14 is inserted into the hole 18 so as to be slidable.

[0023]

As described above, the oxygen blowing apparatus for an electric furnace according to the present invention makes it possible for a worker to be freed from the work of heavy muscles and high temperature environment in front of the electric furnace. It is possible to reduce the unreached range of the oxygen jet flow. Also, it is possible to absorb the impact force received on the tip of the lance, the lance holder, the swing holder, and the swinging device during operation. 1) It is possible to suppress damage to the tip of the lance and extend the life of the lance. It is also possible to prevent damage to itself, operate safely and automate work. 2) The frequency of manually removing the adhered molten metal and slag is reduced, and the effect of eliminating complicated work, which is one of the merits of the non-consumable lance, can be sufficiently exerted. 3) It is possible to reduce the unmelted residue of the scrap by expanding the oxygen jet reach range to the scrap on the side surface of the work mouth, prevent the risk of bumping due to the collapse of the scrap, and extend the processing time by re-adjusting the components. It is possible to extend the power consumption and prevent the deterioration of power consumption. As described above, it greatly contributes to the stability of operation and productivity, and the reduction of energy consumption rate, and its effect is extremely large.

[Brief description of drawings]

FIG. 1 is an overall view of an oxygen blowing device of the present invention and a plan view showing an operating range of a lance body.

FIG. 2 is a configuration diagram showing an impact device provided with a lance swing rod.

FIG. 3 is a partially enlarged view of a work port at a normal time.

FIG. 4 is a partially enlarged view of a work port showing a case where molten metal, slag, and the like adhere to the lance body.

FIG. 5 is a partially enlarged view showing a shock absorber used in the present invention.

FIG. 6 is an overall view of a conventional oxygen blowing device and a plan view showing an operating range of a lance body.

[Explanation of symbols]

 1 Electric Furnace Body 2 Working Port 3 Lance Body 4 Arm 5 Swing Mechanism 6 Swing Hydraulic Cylinder 7-1 Buffer Spring 7-2 Buffer Spring 8 Swing Arm 9 Molten Metal, Slag 10 Fixed Bracket 11 Swing Rod 12 Scrap 13 Tension rod 14 Tip fitting 15 Standby position 16 Blow-in position 17 Ring 18 Guide hole 19 Guide shaft 20 Tip ring

Claims (1)

[Claims] 1. An oxygen blowing device for blowing oxygen or an oxygen-containing gas, comprising an arm for holding an oxygen lance and a turning device for turning the oxygen lance from an evacuation position to an oxygen blowing position of an electric furnace working port. An oxygen blowing device for an electric furnace, comprising a swinging device having a hydraulic cylinder for moving the lance to an arbitrary position in a work mouth, and a swinging device provided on a swinging rod of the oxygen lance. .