JPH06267643A - Conveyer carrying type induction heating device - Google Patents

Abstract

PURPOSE:To prevent the oxidizing abrasion of a metallic part and to extend the service life of a conveyer, by providing a means to process the surface of the metallic part to compose the conveyer, with a graphite water solution to be an oxidization preventive agent. CONSTITUTION:Materials to be heated 1 are loaded on a conveyer 2, passed through a heating coil 3, and heated by the electromagnetic induction. In this case, the metallic part to compose the conveyer 2 is also heated. To the heated metallic part, a graphite water solution to be an oxidization preventive agent solution in a tank 11 is pumped up and spread from a spreader 13 so as to coat the graphite on the surface of the metallic part. The metallic part of the conveyer 2 consists of an austenitic stainless steel, and receives hardly the electromagnetic induction, but it reaches to a high temperature by the conduction from the heated materials 1 and the radiant heat. In this case, the graphite covering the surface of the metallic part prevents the oxidization, because the graphite remains at the major part on the surface layer in the coating condition even though it varnishs partially. Consequently, the oxidizing abrasion of the metallic part is prevented, and the service life of the conveyer is extended.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a conveyor-conveying induction heating apparatus which heats a material to be heated on a conveyor for continuous transfer and heating by electromagnetic induction while passing through a heating coil.

[0002]

2. Description of the Related Art FIG. 2 is a side view showing a conventional conveyor-conveying induction heating apparatus disclosed in, for example, Japanese Patent Laid-Open No. 57-38586, in which 1 is a billet or the like for heating by electromagnetic induction. A material to be heated, 2 is an infinite belt-shaped conveyor for continuously carrying the material to be heated 1 and 3 is a heating coil for heating the material to be heated 1 passing therethrough by electromagnetic induction,
Numerals 4 and 5 respectively support an output side wheel and an input side wheel which support the conveyor 2, 6 a sprocket wheel directly connected to the output side wheel, 7 a drive motor for driving the conveyor 2
Is a sprocket wheel directly connected to the drive motor 7, and 9 is a roller chain engaged with the sprocket wheels 6 and 8.

Next, the operation will be described. Drive motor 7
Rotating force of sprocket wheel 8 and roller chain 9
And is transmitted to the sprocket wheel 6 to drive the delivery wheel 4 to rotate. The conveyor 2 supported by the outlet wheel 4 and the inlet wheel 5 moves in the direction shown by the arrow in the figure, and the material 1 to be heated placed on the conveyor 2 is conveyed and passes through the heating coil 3. Meanwhile, it is heated to a predetermined temperature by electromagnetic induction and sent to the next step. By the way, the metal part of the conveyor 2 is made of non-magnetic austenitic stainless steel and is hard to receive electromagnetic induction, but the heated material 1 is placed on it and passes through the heating coil 3 to heat the heated material 1 from room temperature to about 1250. When it is heated to ℃, the temperature becomes about 650 ℃ at the outlet of the heating coil 3 mainly due to conduction and radiation of heat from the material to be heated 1. This heated metal part is lowered to about 500 ° C. when it comes to the inlet of the heating coil 3 due to natural heat radiation, but is heated to about 850 ° C. again by the heating coil 3 under the influence of heat from the material to be heated 1. When the heating and the natural heat dissipation are repeated and the saturated state is reached, the temperature of the metal portion of the conveyor 2 is increased by the heating coil 3.
The temperature is about 800 ℃ at the inlet and about 1100 ℃ at the outlet, and since it exceeds the oxidation temperature of stainless steel, the oxidation of the metal part progresses and the oxidative consumption becomes severe. FIG. 4 is a graph showing the temperature history of the temperature of the metal portion of the conveyor 2 measured at the inlet and outlet of the heating coil 3.

[0004]

Since the conventional conveyor-conveying type induction heating apparatus is constructed as described above, when the conveyor 2 carries the material to be heated 1 and passes through the heating coil 3, the material to be heated is heated. In addition to being heated by electromagnetic induction, the metal portion that constitutes the conveyor 2 together with 1 is heated to a high temperature mainly due to the heat from the material to be heated 1, reacts with oxygen in the atmosphere to generate scale, and is oxidized. There was a technical problem to be solved that it was consumed and the life was remarkably shortened.

The present invention has been made to solve the above problems, and an object of the present invention is to obtain a conveyor-conveying induction heating apparatus having a long life by preventing the metal portion of the conveyor from being oxidized and consumed.

[0006]

A conveyor-conveying type induction heating apparatus according to the present invention places a material to be heated on an infinite belt-shaped conveyor and continuously conveys the material to be heated to a predetermined temperature by electromagnetic induction while passing through a heating coil. In the case of heating to above, the surface of the metal part constituting the conveyor is treated with an antioxidant solution to provide an antioxidation means for preventing the oxidation.

Further, cooling means is provided for cooling the metal portion constituting the conveyor to an oxidation temperature or lower.

[0008]

The antioxidant means in this invention treats the surface of the metal portion constituting the conveyor with an antioxidant solution,
Even if the metal part is heated by passing through the heating coil, the surface is prevented from being oxidized.

Further, the cooling means cools the metal portion of the heated conveyor to a temperature not higher than the oxidation temperature to prevent oxidation consumption.

[0010]

【Example】

Example 1. FIG. 1 is a side view showing an embodiment of the present invention, and 1 to 9 are the same as those described in the prior art. Reference numeral 11 is a tank containing a graphite aqueous solution of an antioxidant solution, 12 is a pump for pumping the antioxidant solution, and 13 is a dismantler for removing the antioxidant solution. In this embodiment, the antioxidant means comprises a tank 11, a pump 12, a stripper 13 and an antioxidant solution.

This embodiment is constructed as described above. When the rotational force of the drive motor 7 is transmitted to the sprocket wheel 6 via the sprocket wheel 8 and the roller chain 9 and the output wheel 4 is rotationally driven, the output wheel 4 is rotated. The conveyor 2 supported by the inlet wheel 5 moves in the direction of the arrow in the figure, and the material 1 to be heated placed on the conveyor 2 is conveyed and passes through the heating coil 3 and is heated by electromagnetic induction. At the same time, the metal portion forming the conveyor 2 is also heated. The graphite aqueous solution in the tank 11 is pumped up by the pump 12 to the heated metal part, and is removed from the removing device 13 to adhere graphite to the surface of the metal part, and the hot metal part reacts with oxygen in the air. Prevents the scale from being consumed by oxidation. The metal part of the conveyor 2 is made of non-magnetic austenitic stainless steel and is not susceptible to electromagnetic induction. However, when the heated material 1 is heated to, for example, about 1250 ° C., the metal part mainly conducts heat from the heated material 1. And reaches a maximum of about 1000 ℃. Therefore, when the aqueous graphite solution was removed from the metal part of the conveyor 2 and the heated material 1 placed on it was heated to about 1250 ° C., the surface layer of the graphite adhered to the surface of the metal part was oxygen in the air. Although it reacted to react with and became carbon dioxide gas and was dissipated, the other part remained in the state of being adhered, and the oxidation could be prevented. Since the graphite aqueous solution is removed every time the conveyor 2 moves and completes one cycle, the metal portion is not always oxidized.

Example 2. In Example 1, the aqueous graphite solution was removed as an antioxidant solution on the metal portion of the conveyor 2 to form a graphite film on the surface thereof to prevent oxidation. Aluminum phosphate (Al ₂ O ₃ / 3P ₂ O ₅ / 6H ₂ O) aqueous solution,
Or with sodium silicate _{(Na 2 O · nSiO 2 ·} mH 2 O) aqueous solution, it is possible to obtain the same effect by forming a coating film on the surface of the metal part dropwise. Since these coatings are thin, it is necessary to drop these aqueous solutions every time the conveyor 2 makes one cycle, as in the first embodiment.

Further, the method of applying the antioxidant solution to the metal portion of the conveyor 2 was the removal in Example 1 and the dropping in Example 2, but in addition to this, coating or dipping may be used. Further, depending on the characteristics of the antioxidant solution, it is possible to spray it in a mist state.

Example 3. This embodiment is different from the above in that the tank 11 is filled with cooling water, pumped by the pump 12 and removed from the remover 13, and the metal part of the heated conveyor 2 is cooled below its oxidation temperature. Therefore, the cooling means is composed of the tank 11, the pump 12, the remover 13, and the cooling water. When the heated material 1 is heated from room temperature to about 1250 ° C, the conveyor 2
The temperature of the metal portion of the above becomes approximately 650 ° C. at the outlet of the heating coil 3 mainly due to conduction and radiation of heat from the material to be heated 1. When water is removed from the extractor 13 to this metal part and it is cooled, the temperature drops to about 100 ° C. When this metal portion passes through the heating coil 3 again, it is heated to about 650 ° C., and thereafter, the oxidation temperature of the metal portion does not exceed 800 ° C. and oxidation consumption is hardly caused. FIG. 2 is a graph showing the temperature history of the temperature of the metal portion of the conveyor 2 measured at the inlet and outlet of the heating coil 3.

Instead of removing water from the heated metal portion of the conveyor 2 to cool it, the metal portion may be cooled by dropping water, applying water, immersing in water, or spraying mist. The purpose of the period can be achieved.

Example 4. In the third embodiment, the heated metal portion of the conveyor 2 is cooled by removing water, dropping water, applying water, dipping in water, or spraying mist. However, forced air cooling is applied. Also, it is more effective in preventing oxidative consumption.

Embodiment 5. In addition, when oil removal, oil dripping, oil application, or oil immersion is used for cooling the heated metal portion of the conveyor 2, it is similarly effective in preventing oxidative consumption.

[0018]

As described above, according to the present invention,
Since the surface of the metal portion constituting the conveyor is treated with the antioxidant solution and the oxidation preventing means for preventing the oxidation is provided, it is effective in preventing the metal portion of the conveyor from being oxidized and consumed and prolonging its life.

Further, since the cooling means for cooling the metal portion constituting the conveyer to the oxidation temperature or lower is provided, it is possible to prevent the metal portion from being oxidized and consumed and prolong the life.

[Brief description of drawings]

FIG. 1 is a side view showing an embodiment of the present invention.

FIG. 2 is a graph showing a temperature history of a metal portion of a conveyor when there is cooling.

FIG. 3 is a side view showing a conventional conveyor type induction heating device.

FIG. 4 is a graph showing the temperature history of the metal portion of the conveyor when there is no cooling.

[Explanation of symbols]

 1 Heated Material 2 Conveyor 3 Heating Coil 4 Outgoing Wheel 5 Incoming Wheel 6 Sprocket Wheel 7 Drive Motor 8 Sprocket Wheel 9 Roller Chain 11 Tank 12 Pump 13 Remover

Claims (6)

[Claims] 1. A surface of a metal part constituting the conveyor, wherein a material to be heated is placed on an infinite belt-like conveyor and continuously conveyed, and is heated to a predetermined temperature by electromagnetic induction while passing through a heating coil. A conveyor-conveying induction heating device, characterized in that it is treated with an antioxidant solution to provide an oxidation preventing means for preventing oxidation. 2. An antioxidant solution is used as a graphite aqueous solution,
The conveyor-conveying induction heating apparatus according to claim 1, wherein the induction heating apparatus is one of a monoaluminum phosphate aqueous solution and a sodium silicate aqueous solution. 3. A material in which a material to be heated is placed on an infinite belt-shaped conveyor and continuously conveyed, and is heated to a predetermined temperature by electromagnetic induction while passing through a heating coil, and a metal portion constituting the conveyor is oxidized. A conveyor-conveying induction heating apparatus, characterized in that a cooling means for cooling the temperature below the temperature is provided. 4. The conveyor-conveying induction heating apparatus according to claim 3, wherein water removal, water dropping, water application, water immersion or mist spraying is used as the cooling means. 5. The conveyor-conveying induction heating device according to claim 3, wherein forced air cooling is used as the cooling means. 6. The conveyor-conveying induction heating apparatus according to claim 3, wherein oil removal, oil dropping, oil application, or oil immersion is used as the cooling means.