JPH0728558Y2 - Non-ferrous metal melt holding furnace and its heater - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a holding furnace for molten metal of non-ferrous metals such as aluminum and zinc, and an immersion type heater suitable for use in this holding furnace.

[0002]

2. Description of the Related Art As a non-ferrous metal molten metal holding furnace, in order to heat and hold the molten metal contained in the molten metal container, an immersion heater equipped with a heating element in a protective tube made of refractory such as ceramic is installed on the sidewall of the molten metal container. It is constructed in the same manner as that of a system in which it is penetrated and provided horizontally near the bottom of the container (Japanese Utility Model Laid-Open No. 59-153059, Japanese Utility Model Laid-Open No. 60-21699, Japanese Patent Laid-Open No. 61-55576). Immersion heater that penetrates the lid of the molten metal container and is installed vertically inside the container
No. 7396, No. 60-21699, No. 61-7758
No. 8) is known.

[0003]

In the former type of non-ferrous metal molten metal holding furnace, since the heating part of the immersion heater is horizontally installed near the bottom of the molten metal container, heat is generated during operation of the holding furnace. The part is not exposed on the surface of the molten metal, and the holding furnace has good heat transfer efficiency to the molten metal and is preferable in terms of energy saving, but when replacing the immersion heater due to troubles etc.,
After pumping out the molten metal contained in the molten metal container until then, the container must be cooled to some extent and then replaced, which requires a long time for replacement and restoration, and when the protective tube is damaged. There is a problem that it is dangerous because hot water leaks.

On the other hand, in the latter type non-ferrous metal molten metal holding furnace, the immersion heater is provided vertically with the lid penetrating through it. Since it can be replaced outside the furnace by removing the lid without pumping out the molten metal, it is relatively easy to replace and restore it, but the surface of the immersion heater fluctuates during operation of the holding furnace. It is exposed above the level of the molten metal, and the temperature of the protective tube in that part becomes high, which causes the molten metal adhering to the outer peripheral surface to oxidize and solidify (for example, corundum), and the protective tube is damaged due to the difference in thermal expansion coefficient from this solidified layer There is a problem that the immersion heater shortens the life of the immersion heater, the quality of the molten metal is impaired by the generated oxide, and the heat transfer efficiency to the molten metal is inferior to that of the former method. .

The present invention has been made in view of the above-mentioned problems, and it is easy to replace the immersion heater, so that even if the immersion heater is damaged, there is no leakage of water and the transmission to the molten metal. It is an object of the present invention to provide a non-ferrous metal molten metal holding furnace with high thermal efficiency, and to provide a non-ferrous metal molten metal holding furnace heater suitable for constituting such a holding furnace.

[0006]

In order to achieve the above object, the non-ferrous metal molten metal holding furnace of the present invention has an immersion heater tube equipped with a heating element inside, which is located close to the inner bottom of the molten metal container. It hangs horizontally on the furnace lid.

In the holding furnace, it is preferable that the outer periphery of the furnace lid along the outer side of the molten metal container is provided with legs longer than the vertical length of the immersion heater tube.

Further, one of the heaters for holding a non-ferrous metal melt according to the present invention is a bottomed horizontal immersion heater tube having a heating element provided therein and a bottomless vertical immersion tube having a flange at the upper end. The L-shaped bent tube is formed, and a support rod having a flange at the upper end is attached to the outer side of the horizontal immersion heater tube on the bottom side in parallel with the bottomless vertical immersion tube.

[0009] One is to attach a bottomless vertical immersion pipe having a flange at the upper end to both ends of a horizontal immersion heater pipe equipped with a heating element through curved pipes so that the whole is U-shaped.
It is formed in a letter shape.

[0010]

In the non-ferrous metal molten metal holding furnace having the above-mentioned structure, the immersion heater tube having the heating element inside is placed vertically near the inner bottom of the molten metal container on the furnace lid. The heat transfer efficiency is good, the molten metal does not leak even if the immersion heater tube is damaged, and the immersion heater can be replaced by removing the lid, and replacement and restoration can be completed in a short time.

Further, by providing a leg longer than the vertical length of the immersion heater tube on the outer peripheral portion of the furnace lid along the outside of the molten metal container, when the lid is removed due to a trouble in the holding furnace or the like, the immersion heater is used. The tube can be placed on the working floor as it is without any damage, and the replacement work can be facilitated when replacing the immersion heater tube.

Further, in the heater for holding a non-ferrous metal molten metal having the above-mentioned structure, a bottomless vertical immersion pipe having a flange at the upper end is provided at least at one end of the horizontal immersion heater pipe as a heat generating portion so that it can be held by the lid. Since it is configured, it is possible to provide a lead wire to the heating element or a lead wire such as a thermocouple for temperature measurement through the vertical immersion pipe. Further, since the vertical immersion pipe is separated from the heat generating portion and is not heated more than necessary, no oxide is generated at the boundary with the molten metal surface. Further, at the other end of the horizontal immersion heater tube, a support rod having a flange at the upper end or a bottomless vertical immersion tube having the same shape as the bottomless vertical immersion tube is provided, so that the other end can be held by the lid. Since the horizontal immersion heater tube is configured to have both ends supported by the lids, the horizontal immersion heater tube has a structure capable of sufficiently withstanding the molten metal head pressure when used in the holding furnace.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional explanatory view of a non-ferrous metal molten metal holding furnace of the present invention. In the figure, reference numeral 1 is a molten metal container for containing a molten metal M, and a lid 2 is placed on the ceiling portion thereof.

Reference numeral 3 is an L-shaped immersion heater. The immersion heater 3 is provided while being held on the upper surface of the lid 2 by a flange 5 provided on the outer periphery of the upper end of the vertical immersion pipe 4, The other end of the horizontal dipping tube 7 containing the heating element 6 is held on the upper surface of the lid 2 by a flange 9 provided on the outer circumference of the upper end of a support rod 8 attached thereto.

Reference numeral 10 denotes a leg, which is longer than the vertical dip pipe 4 holding the horizontal dip pipe 7 and has a lid 2
Are provided on the front, rear, left and right outer peripheral surfaces of the immersion heater 3 so that when the lid 2 is removed from the molten metal container 1 and placed on the working floor, the immersion heater 3 does not touch and damage the working floor.

In the non-ferrous metal molten metal holding furnace of the present invention having the above-described structure, the horizontal dipping pipe 7 containing the heating element 6 is horizontally provided close to the inner bottom of the molten metal container 1 and is transferred to the molten metal M. The thermal efficiency is good, and the generation of oxides on the outer surface of the dip tube 7 is extremely small. Further, even if the horizontal immersion pipe 7 is damaged, the molten metal does not leak out of the furnace. Further, the immersion heater 3 can be replaced by removing the lid 2, and in this example, the lid 10 is provided with the legs 10, so that replacement and restoration can be performed in a short time.

Still further, the horizontal dipping pipe 7 serving as a heat generating portion.
Both ends of which are held by the lid 2 by the vertical dip pipe 4 and the support rods 8. The static pressure of the molten metal in the molten metal container 1 and the movement of the molten metal M when the lid 2 is removed from the molten metal container 1 Can withstand pressure sufficiently.

FIGS. 2 to 6 are explanatory views of the heater for holding a non-ferrous metal melt according to the present invention, showing the L-shaped immersion heater 3 and the support rod 8 in more detail. .

The vertical dip tube 4, the horizontal dip tube 7 and the connecting bending tube 11 for forming them into an L shape are each made of ceramic and are joined by adhesion. Inside the horizontal immersion pipe 7, a heating element 6 is loaded with a support 12 attached at its tip, and the lead wire of the heating element 6 is covered with an insulator 13 so that the inside of the connecting bending tube 11 and the vertical immersion tube 7 are covered. It is drawn out on the flange 5 at the upper end of the vertical immersion pipe 4 through the inside of the pipe 4. In addition, 14a is a detection rod for detecting molten metal leak, and 14b is a thermocouple for detecting temperature.

The support rod 8 is a ceramic hollow tube 16 in which a flange 9 is formed at the upper end and a heat insulating material 15 is filled inside.
And a donut-shaped ceramic disc body 17 joined to the lower end of the hollow pipe 16, and a projection 19 formed integrally with the tip of the horizontal immersion pipe 7 is loosely fitted in the hollow portion 18 of the disc body 17. The horizontal dipping pipe 7 is supported by the above.

Since the heater for holding a non-ferrous metal melt according to the present invention is constructed as described above, the flange 5 at the upper end of the vertical immersion pipe 4 and the flange 9 at the upper end of the support rod 8 are attached to the upper surface of the lid 2 of the holding furnace. The molten metal container 1 for holding the molten metal M is provided with the horizontal immersion pipe 7 having the heating element 6 built therein.
It can be installed horizontally, close to the inner bottom of the.

[0022]

As described above, according to the non-ferrous metal molten metal holding furnace according to the present invention, the heating part of the immersion heater is vertically provided on the furnace lid in the vicinity of the inner bottom of the molten metal container of the holding furnace. As a result, the immersion heater can be easily replaced, even if the immersion heater is damaged, there is no leakage of molten metal, the efficiency of heat transfer to the molten metal is improved, and there is little oxidation of the molten metal in the heat generating part, maintaining the quality of the molten metal, etc. Have the effect of.

Also, according to the heater for holding a non-ferrous metal melt according to the present invention, a horizontal immersion heater tube having a heating element inside is provided by providing a vertical immersion tube and a support rod on the lid of the holding furnace. , Can be horizontally provided close to the inner bottom of the molten metal container.

[Brief description of drawings]

FIG. 1 is a sectional view of a non-ferrous metal molten metal holding furnace according to the present invention.

FIG. 2 is a partial sectional front view of a non-ferrous metal melt holding furnace heater according to the present invention.

FIG. 3 is a right side view of FIG.

FIG. 4 is a left side view of FIG.

FIG. 5 is a top view of FIG.

FIG. 6 is a bottom view of FIG.

[Explanation of symbols]

1: Molten metal container 2: Lid
3: Immersion heater 4: Vertical immersion pipe 5: Flange
6: Heating element 7: Horizontal immersion tube 8: Support rod
9: Flange 10: Leg 11: Curved pipe for connection 1
2: Support 13: Insulator 14a: Detection rod 14
b: Thermocouple 15: Insulation 16: Hollow tube 1
7: Disc body 18: Hollow part M: Molten metal

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location F27D 11/02 A 7727-4K H05B 3/82 7715-3K

Claims (4)

[Scope of utility model registration request] 1. A non-ferrous metal molten metal holding furnace characterized in that an immersion heater tube having a heating element provided therein is provided horizontally near a bottom of a molten metal container so as to vertically hang on a furnace lid. 2. A non-ferrous metal molten metal holding furnace according to claim 1, wherein legs are provided along the outer side of the molten metal container on the outer peripheral portion of the furnace lid, the legs being longer than the vertical length of the immersion heater tube. 3. A horizontal immersion heater tube having a bottom, which is internally provided with a heating element, and a bottomless vertical immersion tube having a flange at its upper end, which are formed in an L shape by a curved tube, and the horizontal immersion heater. A heater for holding a molten non-ferrous metal, wherein a support rod having a flange at its upper end is attached to the outside of the bottomed side of the pipe in parallel with the bottomless vertical immersion pipe. 4. A bottomless vertical immersion pipe having flanges formed at the upper ends is attached to both ends of a horizontal immersion heater pipe having a heating element inside through curved pipes to form a U-shape as a whole. A heater for holding a molten non-ferrous metal, which is characterized in that