JP2000329476A - Channel type induction furnace - Google Patents

Abstract

PROBLEM TO BE SOLVED: To give an intentional thrust to molten metal in a channel and thereby to make the molten metal in the channel circulate with that in a molten metal chamber, in order to lessen a temperature difference between the molten metal in the channel and that in the molten metal chamber by making the molten metal in a channel part circulate with that in the chamber. SOLUTION: This channel type induction furnace has a constitution wherein an induction coil 3 is fitted on one side of a core 2 formed by laminating ferromagnetic steel sheets so that they form a quadrilateral and wherein a U-shaped channel 4 is formed of refractory outside the induction coil 3 and an opening part of the channel 4 is made to communicate with a molten metal chamber 6 formed of the refractory. In this case, an electromagnetic thrust for making the molten metal in the channel move in a prescribed direction along the channel is given to the metal by a shifting magnetic field so that the molten metal in the channel may circulate into the molten metal chamber.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a groove-type induction furnace in which a molten metal in a groove is circulated with a molten metal in a bath room to reduce a temperature difference between the molten metal in the groove and the molten metal in the bath room.

[0002]

2. Description of the Related Art FIG. 3 is a sectional view of a conventional example. In FIG. 3, reference numeral 1 denotes an induction coil (primary coil) 3 on one side of an iron core 2 in which ferromagnetic steel sheets are laminated so as to form a quadrilateral.
So that a substantially U-shaped groove 4 is formed on the outer peripheral side of the induction coil 3 with a refractory, and the opening of the groove 4 is connected to a hot water chamber 6 formed of a refractory with a connecting portion called a throat 5. 3 shows an inductor. Although not shown, the hot water chamber 6 has a passage extending from the vicinity of the bottom thereof to the tap hole obliquely upward through the refractory forming the hot water chamber 6 and another passage having the same configuration and passing through the refractory material to the hot water outlet. , And the upper part is sealed with a refractory lid. With the above configuration, the molten metal in the hot water chamber 6 of this grooved induction furnace is a so-called molten metal so that the opening of the passage to the hot water outlet and the hot water outlet in the hot water chamber 6 is always below the upper surface of the molten metal. And the hot water from the hot water outlet is added on top of the hot water. The induction coil 3 is always energized while the molten metal is present in the remaining hot water or in the hot water chamber 6 in a state of receiving the hot water, and the groove 4 on the outer peripheral side of the induction coil 3 forms one turn with the throat 5. As a result, an induced current flows, and the molten metal in the groove is heated by Joule heat. This Joule heat is transmitted to the molten metal in the hot water chamber 6 by convection and heat conduction, and the temperature of the molten metal in the hot water chamber 6 is raised.

[0003] As described above, this grooved induction furnace receives molten metal melted in another melting furnace and raises the temperature to a desired temperature, or receives the molten metal in the grooved induction furnace while focusing on melting. The molten metal is dispensed into a tribe at an appropriate time, and serves as a buffer for preventing the molten metal poured into the mold from being cut until the molten metal is discharged from the next melting furnace.

[0004]

By the way, in the conventional configuration, the heat source for keeping the temperature of the molten metal in the bath room or increasing the temperature is the Joule heat of the molten metal in the inductor 1, and the transfer of the Joule heat is caused by convection and heat conduction. I rely on inductor 1
The temperature of the molten metal inside is 100-150 ° C compared to that of the bath room
There is a problem of getting higher. (If the temperature of the molten metal in this groove rises, the life of the refractory forming the groove is shortened.) In order to prevent overheating in this groove, the current of the induction coil is concentrated at substantially the center in the longitudinal direction of the induction coil. If the current flowing in the groove is not made to flow concentrically with the current of the induction coil, and the current flows in the symmetrical groove when an asymmetrical groove is formed, for example, half of the groove deviates from the concentric circle. It is known that the electromagnetic force is received in the direction in which the groove contents are discharged from the groove due to the electromagnetic force in the direction in which the groove contents are asymmetrically removed, and as a result, the groove contents and the like and the molten metal in the bath room circulate. Have been.

[0005] However, the stirring in this case is based on the electromagnetic thrust generated secondarily at the time of heating, and it is impossible to control only the thrust of the molten metal. The present invention has been made to solve the above-mentioned problem, and an object of the present invention is to give intentional thrust to the molten metal in the groove and circulate the molten metal in the hot water chamber so that the temperature of the molten metal in the inductor groove is reduced. It is an object of the present invention to provide a groove induction furnace in which the molten metal in the gutter and the molten metal in the gutter are transmitted quickly to the molten metal in the gutter so that the molten metal in the gutter becomes uniform.

[0006]

According to a first aspect of the present invention, a primary coil is mounted on one side of an iron core in which ferromagnetic steel sheets are laminated so as to form a quadrilateral. In a groove induction furnace which is formed by forming a U-shaped groove on the outside with a refractory and connecting the opening of the groove to a hot water chamber formed of the refractory, the moving magnetic field causes the molten metal in the groove to extend along the groove. It is characterized in that an electromagnetic thrust moving in a certain direction is applied so that the molten metal in the groove circulates in the chamber.

With the above structure, when a moving magnetic field B is applied to the molten metal in the groove from the outside, a current I is induced in the groove by the moving magnetic field, and Fleming's right-hand rule is generated between the current I and the moving magnetic field B. (See FIG. 2). Since this force becomes a thrust for moving the molten metal in the groove, it is possible for the operator to apply a thrust to the molten metal in the groove and circulate the molten metal in the gutter and the molten metal in the gutter and the molten metal in the chamber. And soaking.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a configuration diagram of a main part of an embodiment of the present invention. In FIG. 1, members denoted by the same reference numerals as those of the conventional example have approximately the same functions, and therefore description thereof will be omitted. 1, an induction coil (primary coil) 3 is mounted on one side of an iron core 2 in which ferromagnetic steel sheets are stacked so as to form a quadrilateral, and a substantially U-shaped groove 4 is formed on the outer peripheral side of the induction coil 3. An inductor formed of refractory material and having an opening of the groove 4 connected to a hot water chamber 6 formed of a refractory material at a connection part called a throat 5, and the inductor 7 moves from the outer peripheral side of the groove 4 to the molten metal in the groove 4. An electromagnetic stirrer 8 that generates a thrust in the molten metal in the groove 4 by applying a magnetic field, and 8 denotes a passage leading from the vicinity of the bottom of the hot water chamber 6 to the obliquely upper tap hole through the refractory forming the hot water chamber 6. Although not shown, the hot water chamber 6 has the same configuration as the passage 8 to the tap hole, and has another passage that passes through the refractory and leads to the receiving port, and the upper portion is sealed with a refractory lid. With the above configuration, the molten metal in the hot water chamber 6 of this grooved induction furnace is configured such that the openings in the hot water chamber 6 of the passage 8 to the tap hole and the passage to the receiving port are always molten metal and lower than the upper surface of the molten metal. Molten so-called hot water is left, and the hot water from the hot water outlet is added on top of the hot water. The induction coil 3 is always energized while the molten metal exists in the remaining hot water or in the hot water chamber 6 in a state of receiving the hot water, and the groove 4 on the outer peripheral side of the induction coil 3
Forms a one-turn with the throat 5, an induced current flows, and the molten metal in the groove is heated by Joule heat.
This Joule heat is transmitted to the molten metal in the hot water chamber 6 by convection and heat conduction, and the temperature of the molten metal in the hot water chamber 6 is raised. An electromagnetic stirrer 7 for applying a moving magnetic field to the molten metal in the groove 4 is mounted outside the groove 4. By operating the electromagnetic stirrer 7, a thrust is applied to the molten metal in the groove 4 to mount the electromagnetic stirrer 7. The molten metal in the groove 4 on the drained side is discharged out of the groove 4, and the molten metal that supplements the molten metal in the discharged groove is sucked into the groove from the opening of the other groove. As a result, the molten metal in the groove circulates with the molten metal in the bath room 6.

[0009]

According to the present invention, the molten metal in the groove and the throat portion is prevented from being overheated by forcibly discharging the molten metal in the groove so that the molten metal in the groove does not stay. . In addition, utilizing the momentum of the molten metal discharged from the groove portion, the molten metal in the bath room is also agitated, so that the molten metal is uniformly heated and homogenized. In addition, in the conventional stirring method, it is impossible to control only the stirring because electromagnetic thrust is generated according to the electric current that generates Joule heat in the groove, but it is necessary to raise the temperature as in the homogenization of the additive. However, there is an effect that it can easily cope with a case where only stirring is required or a case where an electromagnetic thrust which does not correspond to heating in the groove is required. Furthermore, the electromagnetic stirrer can be installed in a non-contact manner with the inductor, so it can be easily moved at the time of furnace construction (replacement of the refractory of the furnace), such as removal of the inductor, and it is relatively easy to install in the existing furnace. Additional equipment can be provided.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a main part of an embodiment of the present invention.

FIG. 2 is a principle diagram of an electromagnetic stirrer.

FIG. 3 is a configuration diagram of a conventional example.

[Explanation of symbols]

 7 Electromagnetic stirrer

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4K046 AA01 AA07 BA01 CA01 CD02 CD20 4K063 AA04 AA12 BA02 CA03 FA35 FA38

Claims (1)

[Claims] 1. A primary coil is mounted on one side of an iron core in which ferromagnetic steel sheets are laminated so as to form a quadrilateral, and a U-shaped groove is formed outside the primary coil with a refractory material, and an opening of the groove is formed. In a grooved induction furnace configured to communicate with a hot water chamber made of refractory material, a moving magnetic field gives an electromagnetic thrust to move the molten metal in the groove in a certain direction along the groove, and the molten metal in the groove enters the hot water chamber. A channel induction furnace characterized by being circulated.