JPH01271055A - Running method of electromagnetic pump for pouring molten metal or stopping pouring - Google Patents

Abstract

PURPOSE:To facilitate the works of melting and pouring a molten metal by preheating the passage of a molten metal by heating the core arranging at the molten metal passage by inducing it by the frequency fit for induction heating and pouring or stopping the molten metal by operating as an electromagnetic pump after completion of the preheating. CONSTITUTION:A core 3 is heated by electrifying prior to inputting a molten metal 2 and setting the frequency capable of the induction heating reaching to the specified preheating temp. for the diameter of the core 3 by a frequency convertor. The protection layer 9 made of a refractory material is coated on the outer periphery of the core 3 and a cylindrical linear coil 4 is composed of a core 7 and coil 8. The most effective place for the thrust generation of the electromagnetic pump part easy to be solidified most of a molten metal passage 6 is concentrically preheated by the heating of the core 3 itself. The optimum frequency for giving thrust to the molten metal is reset at the time when preheating is completed, the molten metal is input and the pouring and stoppage of the molten metal are executed according to the work plan by the electromagnetic pump action. The manufacturing cost of the device is thus reduced and the melting and molten metal pouring works can be facilitated.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a method for installing a multiphase cylindrical electromagnetic coil around the outer periphery of a molten metal passage that is continuously provided in a furnace body such as a melting furnace that accommodates molten metal. Melting of a structure in which an electromagnetic pump is installed to generate a moving magnetic field in the molten metal and give thrust to the molten metal,
Concerning a method of operating a pouring device. More specifically, in this type of electromagnetic pump, the strength of the magnetic field that moves from the outer periphery of the metallurgical vessel or molten metal passage toward the center decreases, causing the molten metal in the center to fall due to gravity. In order to prevent such phenomena, a magnetic material in the form of a rod-like core is further placed in the center of the molten metal passage to prevent the phenomenon of stopping the molten metal pouring or making it difficult to pour molten metal uniformly inside and outside the molten metal passage. A metallurgical vessel of this type has been used, and it relates to an operating system that makes it possible to preheat the annular refractory material of the molten metal channel at the beginning of the introduction of the molten metal when using this type of metallurgical vessel.

[Prior art] A cylindrical electromagnetic coil is placed around the outer periphery of a metallurgical container such as a melting furnace, and a moving magnetic field is applied to the molten metal to provide thrust to pour the metal, or a moving magnetic field is applied in the opposite direction to the gravity acting on the molten metal. There are metallurgical vessels with electromagnetic pumps that can be activated and stopped pouring against gravity.

In this type of metallurgical container, the strength of the magnetic field that moves from the outer periphery toward the center decreases, allowing the molten metal in the center to fall under gravity, making it easy to pour the molten metal in the desired state. , it is difficult to stop the pouring of the molten metal. Therefore, a metallurgical vessel has been proposed in which a rod-shaped core-shaped magnetic body is further placed in the center of the molten metal passage to compensate for the drop in thrust at the center. ing.

[Problems to be Solved by the Invention] As mentioned above, when performing operations such as stopping and starting pouring of molten metal by further arranging a rod-shaped core-shaped magnetic body in the center of the molten metal passage, the molten metal is metallurgically controlled. Immediately before pouring into the container, thoroughly preheat the pipe made of refractory material that will serve as the passage for the molten metal.
It is necessary to prevent the injected molten metal from solidifying and sticking.

However, in order to divide and pour small volumes of molten metal, it is necessary to downsize the equipment, and to heat with gas or other means as an external heat source, the molten metal passage that accommodates the heating means must be Since the internal volume, particularly the internal diameter, may be so small that installation is impossible or difficult, an effective solution has been desired.

[Means for Solving the Problems] In order to solve this problem, the present invention uses a device in which a rod-shaped core-shaped magnetic material is arranged in the center of the molten metal passage as it is, and installs another preheating device in the molten metal passage. The objective is to establish an operating method that allows the addition of a preheating step without adding any heating means.

As a specific measure, when manufacturing such a melting and pouring device, the diameter and other specifications of the rod-shaped core protected by a refractory material are adjusted to the required preheating temperature according to the metal material to be melted. It is only necessary to install a frequency converter between the power supply and the load.

The operating method is to turn on electricity before pouring molten metal into the melting and pouring equipment, and use a frequency converter to set the appropriate frequency to achieve a pre-heated temperature according to the diameter of the core, and heat the core by induction. Preheat.

Once preheating is completed, the power supplied to the outer cylindrical linear coil and the core is energized by using a frequency converter to set the frequency most suitable for giving the desired thrust to the molten metal. After that, molten metal is added and the electromagnetic pump action is switched to that of the cylindrical linear coil on the outer periphery and the core.

[Example] FIG. 1 is a side view of a melting and pouring apparatus for implementing the method of the present invention, and FIG. 2 is an enlarged view of the inner and outer core portions of FIG. 1.

Before charging the molten metal 2 into the device 1, electricity is applied.

In this case, a frequency converter (not shown) converts the core 3
The core is induction heated by setting a frequency that allows induction heating to reach a predetermined preheating temperature for the diameter of the core. The outer periphery of the core 3 is covered with a protective layer 9 made of a refractory material, and the cylindrical linear coil is composed of a core 7 and a coil 8.

In this case, the principle of heating for preheating is similar to that of a general induction heating device. The heat generated by the core itself intensively preheats the molten metal passage 6, the electromagnetic pump section that is most likely to solidify, and the location that is most effective for generating thrust.

When preheating is completed, the frequency is reset to the most suitable for applying thrust to the molten metal, then the molten metal is introduced, and the molten metal is poured and stopped according to the work plan using the electromagnetic pump action. .

In this method, preheating is performed by induction heating.

After preheating is completed, the frequency is set to be appropriate for the molten metal thrust, and this method satisfies the functions of pouring and stopping the pouring.

For example, in the case of molten aluminum, preheating may be performed at a temperature of approximately 600°C or higher, which is the temperature of the molten aluminum in the molten metal passage section 6. In this case, the temperature of the core does not exceed the Curie point, which is the transition temperature of the magnetic material, and the It can maintain its function as

The necessary and suitable frequency to generate the thrust to be applied to molten aluminum and the frequency necessary for induction heating do not necessarily match, and the electric power required to generate the thrust for boat fishing is
It may be smaller than the electric power required for induction heating.

Therefore, the core after preheating is mostly heated by heat transfer from the molten aluminum, and the core functions as an electromagnetic pump.

[Effect 1.

You can use the melting and pouring equipment that has a rod-shaped core-shaped magnetic material in the center of the molten metal passage as is, and do not install additional heating means for preheating in the molten metal passage. By simply changing the frequency of the current applied to the rod-shaped core, a preheating process can be added to the rod-shaped core before the molten metal is introduced, and after the preheating process is completed, the frequency of the rod-shaped magnetic material can be changed. Since the original function as an electromagnetic pump can be restored by just doing this, the manufacturing cost of the device can be significantly reduced, and melting and pouring operations can also be made easier.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view of a melting and pouring apparatus for carrying out the method of the present invention, and FIG. 2 is an enlarged side sectional view of the inner and outer core portions of FIG. 1. Reference numeral 1 in the drawing: melting and pouring device, 2: molten metal, 3: core core, 4: cylindrical linear core, 5: sump crucible, 6: molten metal passage, 6°
: Side wall of molten metal passage, 7: Core, 8: Coil, 9: Refractory material protective layer.

Claims (1)

[Claims] The molten metal passage is preheated by induction heating the core placed in the molten metal passage at a frequency suitable for induction heating, and after the preheating is completed, it is operated as an electromagnetic pump at a frequency suitable for the electromagnetic pump function of the molten metal to pump the molten metal. A method of operating an electromagnetic pump characterized by pouring hot water or stopping pouring hot water.