JPS644073Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a crucible-type induction furnace, and more particularly to an improvement in the cooling structure of the furnace top castable cement surrounding the upper part of the melting chamber.

A conventional crucible induction furnace has a structure as shown in FIG. In the figure, 1 is a molten metal, and a melting chamber 2 in which the molten metal 1 is placed is formed of a refractory material 3 in the shape of a crucible. Around the dissolution chamber 2,
A water-cooled induction coil 4 is wound in a spiral manner, and the outside thereof is further surrounded by a furnace frame 5 to support the entire furnace.

An upper frame 6 that presses and fixes the induction coil 4 is fitted inside the furnace frame 5, and a furnace top caster is provided on the outer periphery of the melting chamber 2 above the upper frame 6 so as to surround it. Cement 7 is poured and molded.

The crucible-shaped induction furnace configured in this way is
When the molten metal 1 is put into the melting chamber 2 and the induction coil 4 is energized from an AC power source (not shown), an alternating magnetic flux is generated, and when this interlinks with the molten metal 1, an induced current is induced. It is heated by Joule heat generated by resistance with the molten metal 1 itself.

In this induction heating, since the induction coil 4 is of a water-cooled type in which cooling water flows inside, the refractory material 3 in the melting chamber 2 that is in contact with the induction coil 4 is cooled. However, the refractory material 3 at the furnace top of the melting chamber 2 that is not in contact with the water-cooled induction coil 4 and the furnace top castable cement 7 surrounding it are not cooled and reach a high temperature, so the high-temperature parts are water-cooled. Its strength is lower than that of other parts, and cracks are more likely to occur, resulting in lower reliability.

Further, the upper frame 6 that fixes the induction coil 4 is easily deformed and damaged by the expansion of the melting chamber 2 due to the heat of the molten metal 1 and the radiant heat when the molten metal 1 is tapped, and has disadvantages such as having to be repaired in a short period of time. It was hot.

The present invention eliminates the above-mentioned conventional drawbacks, prevents the occurrence of cracks in the furnace top refractory material and furnace top castable cement, and minimizes thermal deformation and damage to the upper frame, thereby extending the life of the furnace body. The purpose is to obtain a crucible-shaped induction furnace.

An embodiment of the present invention will be described in detail below with reference to the drawings.

2 and 3 show an embodiment of the present invention, and the same parts as in FIG. 1 are designated by the same reference numerals.

A sprue 8 is provided at the top, and a water-cooled induction coil 4 is wound in a spiral manner through a coil cement 9 so as to surround the outer periphery of the melting chamber 2 formed of a refractory material 3, and further surround this outside. A furnace frame 5 is provided as shown in FIG. The melting chamber 2 and the induction coil 4 are placed on the bottom refractory 10, and on the top of the induction coil 4,
An upper frame 6 is provided to press and fix this.
A furnace top castable cement 7 is poured and molded onto the upper side of the upper frame 6 so as to surround the furnace top of the melting chamber 2.

A jacket 11 is buried in the furnace top castable cement 7 so as to surround the furnace top of the melting chamber 2. As shown in FIG.
It is formed almost in a ring shape to surround the top of the furnace. Furthermore, the inside is divided into upper and lower parts by a horizontally installed partition plate 12, and the partition plate 12 is cut out at both ends on the side of the sprue 8 so that the upper and lower channels communicate with each other, and a water supply pipe 13 and a drainage pipe are provided in the center. It is connected to a pipe 14 so that cooling water circulates inside.

To explain the operation of the crucible-type induction furnace described above, when the cooling water 15 is supplied from the water supply pipe 13 into the jacket 11 during operation of the induction furnace, the cooling water 15 circulates inside the jacket 11 and drains into the drain pipe 1.
The heated cooling water 15 is drained from the furnace 4 to cool the furnace top castable cement 7 in which the jacket 11 is embedded, as well as the refractory material 3 and the upper frame 6 at the furnace top that come into contact with the furnace top castable cement 7.

As a result, it is possible to reduce the decrease in strength of the furnace top castable cement 7 and the furnace top refractory material 3 to prevent the occurrence of cracks, and also to prevent the occurrence of cracks.
It is possible to prevent the upper frame 6 from being deformed or damaged due to radiant heat or the like when hot water is tapped.

Note that the jacket 11 is as shown in the above embodiment.
The sprue 8 side is not limited to a ring shape with a part cut out, but the sprue 8 side is also connected in a complete ring shape, and an internal partition plate is vertically provided on the side opposite to the sprue 8, and water supply pipes 13 are provided on the left and right sides of the partition plate. A structure in which the drain pipe 14 and the drain pipe 14 are connected may also be used.

As explained above, according to the present invention, it is possible to prevent the occurrence of cracks in the furnace top refractory material and furnace top castable cement, and to extend the life of the furnace body by minimizing thermal deformation and damage to the upper frame. A crucible induction furnace can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional front view showing a conventional crucible-shaped induction furnace, FIG. 2 is a longitudinal sectional front view of a crucible-shaped induction furnace according to an embodiment of the present invention, and FIG. 3 is a perspective view showing the jacket of FIG. 2. be. 1... Molten metal, 2... Melting chamber, 3... Refractory material, 4... Induction coil, 7... Furnace top castable cement, 8... Sprue, 11... Jacket, 1
2... Partition plate, 13... Water supply pipe, 14... Drain pipe, 15... Cooling water.

Claims (1)

[Scope of utility model registration request] A crucible consisting of a melting chamber made of refractory material, an induction coil wound around the melting chamber, and top castable cement installed on the upper periphery of the melting chamber via an upper frame that presses the induction coil. 1. A crucible-type induction furnace, characterized in that a jacket through which cooling water flows is buried in the top castable cement surrounding the furnace top of the melting chamber.