JPH04200958A - Method for automatically controlling magnetic foating type continuous casting system - Google Patents

Abstract

PURPOSE:To automatically control the position of surface of the molten metal and the wire diameter of the casting wire by generating the electric short-circuit signal by bringing the tip of the metallic original wire applied with potential in contact with the surface of the molten metal. CONSTITUTION:The metallic original wire 7 having a sharp tip is applied with the potential preliminarily, and set at the prescribed position in the casting vessel 4. Next, the surface adjusting body 3 arranged in the molten metal holding furnace 1 is pushed down in the arrow mark direction, and the surface of the molten metal 2 is elevated, the surface is brought in contact with the metallic original wire 7, and the short-circuit is generated electrically. When the short-circuit signal is generated, the cooling is began with the cooling device set in the casting vessel 4, the metallic original wire 7 is pulled up with the pulling up roller 8 after a specific delay time, and the cooled and cast metallic wire in contact with the metallic original wire 7 is pulled up and wound. In this time, because the molten metal 2 is consumed following to pulling up the metallic wire, the surface is lowered, so the surface is always measured, and the control is executed so as to supply the molten metal 2 if the difference of the measured position and the initial position attains the prescribed size.

Description

[Detailed Description of the Invention] "Objective of the Invention" (Industrial Application Field) The present invention relates to a casting method for manufacturing long metal products, and more specifically, in a magnetically levitating continuous casting method, the present invention relates to a casting method for manufacturing long metal products, and more specifically, a method for starting a system in a magnetic levitation continuous casting method. This invention relates to a method for automatically controlling a process.

(Prior Art) It has been known to manufacture wire rods or rods made of metals such as aluminum and copper by continuous casting means (Japanese Patent Laid-Open No. 59-1.33958, etc.). . One such method is magnetic levitation continuous casting. This creates an elongated, upwardly traveling alternating magnetic field inside the casting vessel, and introduces molten metal into the alternating magnetic field and into the lower part of the casting vessel to form a column of molten metal that moves upward through the casting vessel. This is a method in which the molten metal column is exposed to an alternating magnetic field and sequentially cooled and solidified as it moves through the casting container, and the cast/formed body is taken out from the top of the casting container, and is an industrially effective method. It is put into practical use.

According to this magnetic levitation continuous casting method, the molten metal column that is cast or formed exhibits a weightless state within an alternating magnetic field. This eliminates the frictional force and adhesive force with the casting container (mold), which not only reduces the need for removal operations, but also ensures that the molten metal column is internally stirred and exhibits a high degree of homogeneity when passing through the alternating magnetic field. This will have the advantage of

(Problems to be Solved by the Invention) However, this conventional magnetic levitation continuous casting method has the following disadvantages, and improvement thereof is desired. In other words, when starting up the system, in order to take the molten metal column upwards from the alternating magnetic field that is the forming area, the tip of the metal wire is brought into contact with the liquid surface of the molten metal, solidified, and then moved at a constant speed. This metal wire is drawn out in a cubic manner to sequentially solidify it. Conventionally, replenishment of the molten metal that decreases with the raising and lowering of the metal base line and casting is performed manually. Therefore, there is a problem in that it is very difficult to maintain the wire diameter of the obtained cast metal wire within a predetermined size range.

Therefore, the present invention has been made to solve these conventional difficulties, and it is necessary to cast long metal pieces using the magnetic levitation continuous casting method. We propose an automated system control method that allows castings of a certain standard to be obtained without any problems.
That purpose.

[Structure of the Invention] (Means for Solving the Problems) The automatic control method of the magnetically levitating continuous casting system of the present invention is as follows.
a short-circuit signal generation step of generating a short-circuit signal by electrically short-circuiting the molten metal lf1 when the generation of the short-circuit signal is detected;
a molten metal liquid level initial position storing step of storing the initial position of the surface in a storage means; and when the occurrence of the short circuit f5 is detected, pulling up the metal base wire after a preset certain delay time has elapsed. A molten metal lfk surface measuring step for constantly measuring the molten metal liquid level position by a measuring means; The molten metal liquid level measurement position and the molten metal liquid level initial position memorized by the molten metal liquid level measurement position recording step are successively compared by the automatic determination means 1 to determine whether or not molten metal replenishment is necessary. A metal liquid level position comparison determination step, a wire diameter i1+11 constant step of measuring the wire diameter of the cast metal wire by a wire diameter measuring means, and a wire diameter measured by this wire diameter measuring step and the wire memorized by a thousand marks. A wire diameter comparison and determination step in which the automatic wire diameter determination means sequentially compares the wire diameter pattern to determine whether the original wire pulling roller is driven or stopped, and the molten metal liquid level position comparison and determination step determines the molten metal liquid level measurement position. and the initial position of the molten metal liquid level is determined to be less than or equal to a predetermined value, and the wire diameter comparison determination step determines that the wire diameter 7ill constant value is within the range of the preset wire diameter pattern. When it is determined that the liquid level difference is less than a predetermined value by the metal wire casting step of casting the metal wire and the molten metal liquid level position comparison and determination step of driving the light beam drawing roller as it is. and a base line pulling roller stopping step for stopping the base line pulling roller when the wire diameter comparison determination step determines that the wire diameter measurement value is out of the range of the preset wire diameter pattern; and the molten metal liquid level position comparison. When it is determined in the determination step that the liquid level position difference exceeds a predetermined value, the calculation means sequentially calculates the amount of molten metal consumed during the casting process from the preset wire diameter and wire speed of the cast metal wire. a molten metal replenishment amount calculation step, and a molten metal replenishment step of replenishing molten metal by an automatic molten metal replenishing means according to the calculation result of this molten metal replenishment amount calculation step, and maintaining the initial position of the molten metal liquid level, It is characterized by having

(Function) In the automatic control method of the magnetic levitation continuous casting method of the present invention configured as described above, molten metal? The tk plane is raised by 2, and the liquid level of the molten metal comes into contact with the tip of the base wire, which has been given a potential of 17, to electrically short-circuit the base wire and the molten metal. By converting human operations such as raising and lowering the molten metal liquid level into electrical signals, automatic control of the process becomes possible.

This short-circuit signal triggers the operation of the cooling means for the casting container, and after a certain delay time has elapsed and the temperature of the casting container reaches the predetermined operating conditions, the pulling of the raw material is started. Material loss can be reduced as much as possible.

In addition, the position of the molten metal liquid level when this short circuit signal is issued is stored in the storage means, and the wire diameter of the metal wire or rod to be cast and the drawing speed of the metal beam are set in advance. From this, the amount of molten metal to be supplemented during the process can be calculated by a calculation device. Therefore, by continuously and automatically monitoring the molten metal level and replenishing the required amount of molten metal as needed, the molten metal level can be maintained at the previously memorized initial position and products of a certain standard can be stably produced. This makes it possible to manufacture

-〇- Furthermore, by sequentially monitoring the wire diameter of the cast metal wire in the same way as the position of the molten metal liquid level, it is possible to automatically detect when the wire pulling roller should be stopped. Therefore, automatic control of the process becomes possible.

(Example) The system automatic control method for the magnetically levitated continuous casting method of the present invention will now be described using the example shown in the drawings.

FIG. 2 is a partial cross-sectional view of the main structure of the casting device used in the magnetic continuous casting method of the present invention.
Reference numeral 1 denotes a molten metal holding furnace that accommodates and holds molten metal 2;
3 is disposed in the molten metal holding furnace 1 so as to be movable downward and adjusts the liquid level of the molten metal 2. A surface adjusting body receives the molten metal 2 from below in the form of a molten metal column. It is a cast container. Reference numeral 5 designates an alternating magnetic field generating means which is integrally disposed around the outer periphery of the casting container 4 and generates an alternating magnetic field that electromagnetically moves the molten metal column received in the casting container 4 upward. Reference numeral 6 designates a cooling means that cools and solidifies the molten metal column moving upward in an alternating magnetic field, and cools the wall of the casting container 4 by supplying cooling water or the like. When the continuous casting system is on standby before starting up, a small amount of cooling water is flowed to protect the machine, and after the system starts up, the cooling water increases in accordance with the preset temperature.

The first No. 7 rains a metal beam, and the tip of the metal beam 7 comes into contact with a molten metal column, which is cooled and solidified one after another, and a metal wire is cast. The metal wire solidified in succession with the metal beam 7 is pulled up and wound up by a beam drawing roller 8, thereby performing continuous casting.

When starting up the continuous casting system, the tip of the metal beam 7 is sharpened in advance, as shown in FIG. 3 or 4, for example. Then, the light beam 7 is set at a predetermined position within the casting container 4 so as not to come into contact with the surrounding structural parts made of electrical conductors.

Alternatively, the vicinity of the tip of the light beam 7 other than the actual part may be insulated in advance by applying heat-resistant enamel (product name: Show Excel, manufactured by Showa Denshin Co., Ltd.) (1i) or by attaching an N sleeve. It is also possible to set the casting container 4 at a predetermined position within the casting container 4.

A pulling roller 8 system for pulling the metal beam 7 is also insulated from the structural part shrine.

Hereinafter, the present invention implemented using the casting apparatus configured as described above will be explained in detail according to flowchart 1 shown in FIG.

In the short circuit signal generation step in the figure, first, the metal beam 7
A potential is applied to the mold while electrically insulating it from surrounding structures, and the mold is set at a predetermined position within the casting container as described above.

To raise the molten metal liquid level by 1", the liquid level adjusting body 3 disposed in the molten metal holding furnace 1 is pushed down in the direction of the arrow to raise the liquid level of the molten metal 2, and the liquid level is raised by the metal beam. By contacting the tip of 7, it is electrically short-circuited and a short-circuit signal is generated. Although the liquid level regulator 3 is moved up and down manually, the steps after generation of this short circuit signal are automatically controlled as described below.

First, the position of the molten metal liquid level in the short circuit (the molten metal holding furnace when No. 8 occurrence is detected) is stored in the storage means as the reference liquid level Ho.
A cooling step (description in flowchart 1. is omitted) for maintaining the temperature at a preset cooling temperature is also started. Then, the pulling roller 8 for pulling up the metal beam 7 is driven after a preset constant delay time.

The pulling roller 8 is driven, and as the metal wire that has been cooled and cast in contact with the metal beam 7 is pulled up and wound up, the molten metal 2 is consumed and the liquid level is lowered. The position of this molten metal liquid level is constantly measured by a measuring means, and this molten metal liquid level measurement position H is compared with the molten metal liquid level initial position H6 stored in the previous molten metal liquid level storage step.

Preferably, the measuring means is one that can perform accurate measurements, such as an ultrasonic measuring method.

At this time, if the difference between the measured position H of the molten metal liquid level and the initial position H1 is less than a predetermined value, the wire diameter D of the metal wire to be cast in succession with the metal beam 7 is measured, Wire diameter pattern D stored in advance. Compare with. The wire diameter pattern D in which the wire diameter measurement value at this time is stored in advance. When it is within the range, the base line pulling roller 8 is driven to continue casting.

On the other hand, wire diameter pattern D has a fixed value of wire diameter flllll. When the base line pull-up roller 8 is stopped, the cooling process is also stopped.

In the molten metal liquid level position comparison determination step, when it is determined that the difference between the al11 fixed position and the initial position of the molten metal liquid level exceeds a predetermined size, the preset wire diameter and wire speed of the cast metal wire are determined. The amount of molten metal consumed during the casting process may be calculated from the above, and molten metal may be replenished accordingly. Note that not only the wire diameter and wire speed in a steady state of operation, but also the head loss immediately after the drive of the wire pulling roller 8 is started is calculated and stored in advance.

In this way, by bringing the tip of the metal beam 7 into contact with the surface of the molten metal 2 and generating an electrical short circuit signal, it is possible to start up the magnetic levitation continuous casting system and automatically control it. Become.

(Effects of the Invention) As explained above, according to the present invention, by using an electrical short circuit signal as a starting point for the system, automatic control of the position of the molten metal liquid level and the wire diameter of the cast metal wire can be performed. become. Therefore, it becomes possible to efficiently and stably continuously cast metal casting wires or rods of a certain standard while minimizing the loss of raw materials.

[Brief explanation of the drawing]

FIG. 1 is a flowchart illustrating the flow of the magnetic levitation continuous casting system automatic control method of the present invention, and FIG. 3 and 4 are schematic diagrams showing examples of the shape of the metal beam tip that can be used in the embodiment of the present invention. ]...... Molten metal holding furnace 2... Molten metal 3... Liquid level adjuster 4... Casting container 5. ......Alternating magnetic field generating means 6...Cooling means 7...Metal beam 8...Round wire pulling roller Applicant
Showa Electric Wire and Cable Co., Ltd. Representative Patent Attorney Sasa Suyama
- (1 other person) = 16-

Claims (1)

[Claims] (1) In the magnetic levitation continuous casting method, a short-circuit signal generation step in which the molten metal liquid level is raised and brought into contact with the tip of the metal wire to which a potential has been applied in advance, causing an electrical short-circuit and generating a short-circuit signal. and a molten metal liquid level initial position storing step of storing in a storage means an initial position of the molten metal liquid level when the generation of the short circuit signal is detected; After a certain delay time has elapsed, a step of starting to drive a pull-up roller for pulling up the metal base wire, and a step of measuring the molten metal liquid level position by constantly measuring the molten metal liquid level position using a measuring means. and successively comparing the molten metal liquid level measurement position measured in this molten metal liquid level position measuring step and the molten metal liquid level initial position stored in the molten metal liquid level initial position storing step by an automatic determination means, A molten metal liquid level position comparison determination step for determining whether molten metal replenishment is necessary; a wire diameter measurement step for measuring the wire diameter of the cast metal wire using a wire diameter measuring means; A wire diameter comparison and determination step in which the wire diameter and a pre-stored wire diameter pattern are successively compared by an automatic wire diameter determination means to determine whether to drive or stop the wire pulling roller; and the molten metal liquid level position comparison and determination step. It is determined that the difference between the molten metal liquid level measurement position and the molten metal liquid level initial position is less than or equal to a predetermined size, and the wire diameter measurement value is within a preset range of a wire diameter pattern in the wire diameter comparison determination step. When it is determined that the difference in liquid level is within a predetermined value or less, a metal wire casting step in which the wire pulling roller is driven as it is to cast a metal wire, and a molten metal liquid level position comparison and determination step are performed so that the liquid level position difference is equal to or less than a predetermined size. and when it is determined in the wire diameter comparison determination step that the wire diameter measurement value is out of the range of the preset wire diameter pattern, a base wire pulling roller stopping step of stopping the base wire pulling roller; When it is determined in the metal liquid level position comparison determination step that the liquid level position difference exceeds a predetermined value, the amount of molten metal consumed during the casting process is determined based on the preset wire diameter and wire speed of the cast metal wire. A molten metal replenishment amount calculation step in which the molten metal replenishment amount calculation step is sequentially calculated by a calculation means; and a molten metal replenishment amount calculation step in which molten metal is replenished by the molten metal automatic replenishment means according to the calculation result of the molten metal replenishment amount calculation step to maintain the initial position of the molten metal liquid level. An automatic control method for a magnetically levitating continuous casting system, comprising: a replenishment step.