JP2746048B2 - Conveyor conveyance type induction heating device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a conveyer-conveying induction heating apparatus in which a material to be heated is placed on a conveyor, conveyed continuously, and heated by electromagnetic induction while passing through a heating coil.

[0002]

2. Description of the Related Art FIG. 2 is a side view showing, for example, a conventional conveyor-carrying induction heating apparatus disclosed in Japanese Patent Laid-Open Publication No. Sho 57-38586. In FIG. The material to be heated, 2 is an infinite belt-like conveyor that continuously carries the material to be heated 1 placed thereon, 3 is a heating coil that heats the material to be heated 1 passing through the inside by electromagnetic induction,
Reference numerals 4 and 5 denote outgoing and incoming wheels respectively supporting the conveyor 2, 6 a sprocket wheel directly connected to the outgoing wheel, 7 a drive motor for driving the conveyor 2, 8
Is a sprocket wheel directly connected to the drive motor 7, and 9 is a roller chain engaged with the sprocket wheels 6, 8.

Next, the operation will be described. Drive motor 7
Rotation force of sprocket wheel 8 and roller chain 9
To the sprocket wheel 6 to rotate the output side wheel 4. The conveyor 2 supported by the outgoing wheel 4 and the incoming wheel 5 is thereby moved 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. During that time, it is heated to a predetermined temperature by electromagnetic induction and sent to the next step. The metal part of the conveyor 2 is made of non-magnetic austenitic stainless steel, and is hardly susceptible to electromagnetic induction. When it is heated to ℃, the temperature of the heating coil 3 reaches about 650 ° C. mainly due to conduction and radiation of heat from the material 1 to be heated. When the heated metal part reaches the inlet of the heating coil 3 due to natural heat radiation, it drops to about 500 ° C., but is again heated to about 850 ° C. by the heating coil 3 under the influence of the heat from the material 1 to be heated. When the heating and the natural heat radiation are repeated and a saturated state is reached, the temperature of the metal part of the conveyor 2 is increased by the heating coil 3.
At about 800 ° C at the inlet and about 1100 ° C at the outlet, the temperature exceeds the oxidation temperature of stainless steel, so the oxidation of the metal part progresses and the oxidation consumption becomes severe. FIG. 4 is a graph showing a temperature history of the temperature of the metal portion of the conveyor 2 measured at the inlet and the outlet of the heating coil 3.

[0004]

Since the conventional conveyor-carrying induction heating apparatus is constructed as described above, when the conveyor 2 places the material 1 to be heated and passes through the heating coil 3, the material to be heated is heated. In addition to being heated by electromagnetic induction, the metal part that forms the conveyor 2 together with 1 becomes high temperature mainly due to the influence of the heat from the material 1 to be heated, reacts with oxygen in the atmosphere to generate scale, and There was a technical problem to be solved that the life was shortened due to wear.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a conveyor-conveying induction heating apparatus having a long service life by preventing oxidative consumption of a metal portion of a conveyor.

[0006]

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

[0007] Further, a cooling means is provided for cooling a metal portion constituting the conveyor to an oxidation temperature or lower.

[0008]

The antioxidant means in the present invention treats the surface of the metal part constituting the conveyor with an antioxidant solution,
Even if the metal part passes through the heating coil and is heated, it prevents oxidation of the surface.

The cooling means cools the heated metal part of the conveyor to an oxidation temperature or lower, thereby preventing oxidation consumption.

[0010]

【Example】

Embodiment 1 FIG. 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. Numeral 11 denotes a tank containing an aqueous solution of graphite as an antioxidant solution, numeral 12 denotes a pump for pumping the antioxidant solution, and numeral 13 denotes a remover 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 side wheel 4 is rotationally driven, the output side wheel 4 is rotated. And the conveyor 2 supported by the entry 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, passes through the heating coil 3, and is heated by electromagnetic induction. At the same time, the metal part constituting the conveyor 2 is also heated. Pump the graphite aqueous solution in the tank 11 to the heated metal part, remove it from the remover 13 and apply graphite on the surface of the metal part, and the hot metal part reacts with oxygen in the air. Prevents oxidation and consumption as a scale. The metal portion of the conveyor 2 is made of non-magnetic austenitic stainless steel and is hardly susceptible to electromagnetic induction. However, when the material 1 to be heated is heated to, for example, about 1250 ° C., the metal portion mainly conducts heat from the material 1 to be heated. Up to about 1000 ° C due to radiation. Thus, when the graphite aqueous solution was removed from the metal part of the conveyor 2 and the material 1 to be heated placed on the metal part was heated to about 1250 ° C., the graphite layer attached to the surface of the metal part showed that the surface layer of the graphite layer had oxygen in the air. , And was dissipated as carbon dioxide gas, but the other portions remained attached, preventing oxidation. Since the graphite aqueous solution is withdrawn every time the conveyor 2 moves and makes a round, the metal portion does not always oxidize.

Embodiment 2 FIG. In the first embodiment, an aqueous graphite solution was withdrawn as an antioxidant solution on the metal portion of the conveyor 2 and a graphite coating was formed on the surface 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 a round as in the first embodiment.

Further, the method of applying the antioxidant solution to the metal portion of the conveyor 2 has been described in Example 1 by removing and in Example 2 by dropping, but other methods such as coating and dipping may be used. Further, depending on the characteristics of the antioxidant solution, it is also possible to spray in a mist state.

Embodiment 3 FIG. In this embodiment, unlike the above, a tank 11 is filled with water for cooling, pumped up by a pump 12, removed from a remover 13, and cooled to a temperature below the oxidation temperature of the heated metal part of the conveyor 2. The cooling means comprises a tank 11, a pump 12, a stripper 13, and cooling water. When the material to be heated 1 is heated from room temperature to about 1250 ° C, the conveyor 2 is heated.
The temperature of the metal portion becomes approximately 650 ° C. at the outlet of the heating coil 3 mainly due to conduction and radiation of heat from the material 1 to be heated. When water is removed from the remover 13 to the metal part and cooled, the temperature falls to about 100 ° C. When the metal portion passes through the heating coil 3 again, it is heated to about 650 ° C., and thereafter, this process is not repeated, and the oxidation temperature of the metal portion does not exceed 800 ° C., and almost no oxidation consumption occurs. FIG. 2 is a graph showing a temperature history of the metal portion of the conveyor 2 measured at the inlet and the outlet of the heating coil 3.

Instead of cooling the metal part of the heated conveyor 2 by removing water, the metal part may be cooled by dropping water, applying water, dipping in water or spraying mist. The purpose of the period can be achieved.

Embodiment 4 FIG. In the third embodiment, the heated metal part of the conveyor 2 is cooled by removing water, dripping water, applying water, immersing in water, or spraying a mist. It is also more effective in preventing oxidative consumption.

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

[0018]

As described above, according to the present invention,
Since the surface of the metal part constituting the conveyor is treated with an antioxidant solution to provide an antioxidant means for preventing oxidation, the metal part of the conveyor is prevented from being oxidized and consumed, and has an effect of extending the life.

Further, since the cooling means for cooling the metal part constituting the conveyor to an oxidation temperature or lower is provided, the metal part can be similarly prevented from being oxidized and consumed, and the life can be prolonged.

[Brief description of the drawings]

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

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

FIG. 3 is a side view showing a conventional conveyor-carrying induction heating apparatus.

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

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Material to be heated 2 Conveyor 3 Heating coil 4 Outlet wheel 5 Inlet wheel 6 Sprocket wheel 7 Drive motor 8 Sprocket wheel 9 Roller chain 11 Tank 12 Pump 13 Removal machine

Claims (6)

(57) [Claims] 1. A method for heating a material to be heated to a predetermined temperature by electromagnetic induction while passing the material to be heated placed on an infinite belt-shaped conveyor and passing through a heating coil, wherein a surface of a metal part constituting the conveyor is provided. A conveyor-conveying induction heating apparatus, characterized in that the apparatus is provided with an antioxidant means for treating the same with an antioxidant solution to prevent oxidation. 2. An antioxidant solution comprising an aqueous graphite solution,
2. The conveyor-carrying induction heating apparatus according to claim 1, wherein the apparatus is one of an aqueous solution of primary aluminum phosphate and an aqueous solution of sodium silicate. 3. A method in which a material to be heated is placed on an infinite belt-shaped conveyor, conveyed continuously, and heated to a predetermined temperature by electromagnetic induction while passing through a heating coil. A conveyor-conveying induction heating device, comprising cooling means for cooling the temperature to a temperature or lower. 4. The conveyor-carrying induction heating apparatus according to claim 3, wherein the cooling means uses water removal, dropping of water, application of water, immersion in water, or spraying of mist. 5. The conveyor-carrying induction heating apparatus 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 the cooling means uses oil removal, oil dropping, oil application, or immersion in oil.