JPH11300466A - Supplying piping, casting device and casting method of molten metal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To keep molten metal temp. in a molten metal furnace to a comparatively low temp. and also, to raise the molten metal temp. in a supplying tube passage to an optimum temp. in casting. SOLUTION: The supplying tube passage 1 for supplying molten aluminum A into a mold from a molten metal furnace of a holding furnace or a melting and holding furnace, etc., is composed of a heat-insulating tube 2 formed as a molten metal flowing-inlet 25 at the one end side and a molten metal flowing outlet 27 at the other end side, an electric heating sheath-heater 3 arranged in the heat-insulating tube 2 and an electric power supplying device 31 to the heater. In this way, the durability of the molten metal furnace is improved and also, a casting can be executed in good efficiency with small amount of energy. Further, the oxidizing of the molten metal in the molten metal furnace can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molten metal supply line for transferring a high-temperature molten metal, a casting apparatus using the supply line, and a casting method.

[0002]

2. Description of the Related Art Casting is a method in which molten metal (metallic metal) melted in a centralized melting furnace is transferred to a holding furnace arranged near a mold such as a die casting machine by a transportation means such as a hot water distribution lift or a cart, or It is performed by a method of melting in a hand melting furnace arranged near a mold. In addition, in a molten metal furnace such as a holding furnace or a hand melting furnace, heating means such as a burner and an electric heater are additionally provided to maintain a high temperature suitable for pouring the molten metal into a mold.

[0003]

It is necessary to maintain the molten metal in a molten metal furnace such as a holding furnace or a hand melting furnace at a high temperature suitable for casting. Therefore, there is a problem that the durability of the molten metal furnace is low due to the deterioration of the furnace material due to the high temperature, and the energy efficiency is low because the high temperature is maintained. Further, since the higher the temperature of the molten metal in air, the more the oxidation is promoted, it is desirable to keep the temperature as low as possible and raise the temperature to a high temperature suitable for casting just before casting in the mold.

An object of the present invention is to maintain a molten metal in a molten metal furnace such as a holding furnace or a hand melting furnace at a relatively low temperature, and to supply a molten metal from the molten metal furnace to a mold. An object of the present invention is to provide a molten metal supply pipe capable of raising the temperature of a molten metal to a temperature optimum for casting in the passage.

[0005]

SUMMARY OF THE INVENTION The present invention relates to a supply pipe for supplying a molten metal from a molten metal furnace such as a holding furnace or a hand melting furnace to a mold, one end of which is provided with a molten metal inlet. It consists of an insulated pipe whose end is an outlet for molten metal, and a heater arranged in the insulated pipe. As the heater, an electric-heated sheathed heater is preferable, and an energizing device for the heater is additionally provided.

[0006]

When the molten metal supply line of the present invention is used, the temperature of the molten metal in the molten metal furnace is maintained at a relatively low temperature, and the optimal temperature for casting the molten metal by the heater in the adiabatic tube. Can be maintained. For this reason, the durability of the molten metal furnace is improved and casting can be performed efficiently with less energy. Further, since the molten metal in the molten metal furnace has a low temperature, oxidation can be reduced.

According to the second aspect of the present invention, a rod-shaped sheathed heater is arranged along the center of the heat insulating pipe as an electric heater. In this case, the heat generated by the heater can be efficiently transmitted to the molten metal in the supply pipe, and the energy cost can be reduced. According to the third aspect of the present invention, when a predetermined amount of molten metal is supplied from the inflow port to the molten metal in an amount reaching the outlet in the supply pipe, the predetermined amount of molten metal is cast into a mold. Can be included. In this case, since the amount of the molten metal in the supply pipe is always constant, the temperature can be easily controlled. According to the configuration of the fourth aspect, the contact area between the high-temperature molten metal and the air can be reduced, and oxidation can be prevented.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described with reference to the embodiments shown in FIGS. FIG. 1 shows a supply line 1 for molten metal, and FIG. 3 shows a mold C from a molten metal furnace B such as a holding furnace, a hand melting furnace or the like through a supply line 1.
1 shows a casting device for successively transferring and casting into a casting machine.

The supply line 1 has a flow path 20 of a molten metal inside.
And an electrothermal sheath heater 3 disposed in the flow path 20. The heat insulating tube 2 includes a metal sleeve 21 and a heat insulating layer 22 surrounded by the sleeve 21 and having the flow path 20 formed therein. The flow path 20 has a circular cross section in this embodiment, and has an intermediate stagnation portion 23 in which the molten metal stagnates in the middle and the electrothermal sheath heater 3 is attached along the center. A part or all of the cross section of the flow path 20 may be formed in a shape other than a circle such as a polygon, an ellipse, and an ellipse.

At one end (left end in the figure) of the intermediate stay portion 23,
Each of them has a circular cross section, and a throat 24 inclined upward and an inflow port 25 extends horizontally from an end of the throat 24. At the other end of the intermediate retaining portion 23, a ridge portion 26 having a circular cross section, inclined upward and set to the same level as the substantially middle position of the throat portion 24, And an outflow port 27 which is inclined. In this example,
In order to prevent the aluminum hot water A from being oxidized, the cross sections of the bank 26 and the throat 24 are reduced so as to minimize the area of the hot water surface.

The electric-heated sheathed heater 3 is a rod-shaped sheathed heater.
Is inserted along the center of the intermediate retaining portion 23 from the insertion port 32 attached to the inflow port 25 side. It should be noted that a plurality of rod-shaped sheathed heaters may be mounted according to the required heat generation amount, the cross-sectional area of the intermediate stagnation section 23, and the like, and the shape of the sheathed heater may be other than linear, such as planar.

The molten metal supply line 1 is provided with an aluminum bath A whose temperature is controlled at 650 ° C. in a molten metal furnace B,
A predetermined amount is supplied from the inlet 25. Intermediate stay part 23
750 of aluminum water A of 2 to 4 times the predetermined amount
Temperature is controlled at ℃ and stays. Therefore, the outlet 2
The aluminum melt A at a temperature of 7 to 750 ° C. is extruded by the predetermined amount and cast into a mold C.

The heat insulating pipe 2 may be curved in a substantially J-shape, and the inflow port 25 at one end may be directed upward. In this case, the inflow of the aluminum bath A can be carried out smoothly. Further, as the electric-heated sheathed heater 3, one that is curved in a substantially U-shape or the like along the shape of the flow path 20 may be used. Further, the intermediate retaining section 23
The temperature control of the aluminum hot water A in the inside is performed by attaching a temperature sensor to the intermediate stagnation section 23 and performing feedback control, or calculating or measuring a required amount of heat in advance and performing feedforward control. In addition, another heat source such as a burner can be used for the heater.

[Brief description of the drawings]

FIG. 1 is a front sectional view of a supply pipe for molten metal.

FIG. 2 is a side sectional view of a supply pipe for molten metal.

FIG. 3 is a schematic view of a casting apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Molten metal supply pipe 2 Heat insulation pipe 3 Electric heat type sheathed heater 21 Bush tube 22 Heat insulation layer 23 Intermediate stay part 24 Throat part 25 Inlet 26 Inlet 26 Drain part 27 Outlet 31 Electricity device B Molten metal furnace C Mold

Claims (6)

[Claims] 1. A supply line for supplying molten metal from a molten metal furnace such as a holding furnace or a hand melting furnace to a mold, wherein one end has an inlet for molten metal and the other end has an outlet for molten metal. A supply pipe for molten metal, comprising a heat insulating pipe having a shape and a heater disposed in the heat insulating pipe. 2. The molten metal supply pipe according to claim 1, wherein the heater is a rod-shaped electrothermal sheath heater, and is arranged along the center of the heat insulating pipe. Supply pipeline. 3. The molten metal supply pipe according to claim 1, wherein the heat insulating pipe is provided at a position where the heater is disposed and a horizontally-long intermediate portion where the molten metal stays, and is positioned higher than the intermediate portion. It is characterized by comprising the outflow port inclined downward through a levee having a small sectional area, and the inflow port inclined upward through a throat having a small sectional area set at the same position as the ridge. Molten metal supply line. 4. The molten metal supply pipe according to claim 3, wherein the bank and the throat have a smaller cross-sectional area than the intermediate part, the inlet and the outlet. Metal supply pipeline. 5. A molten metal furnace such as a holding furnace or a hand melting furnace, means for feeding molten metal in the molten metal furnace, and a molten metal supply line according to any one of claims 1 to 4, A casting device comprising: means for injecting into a mold connected to the outlet. 6. A molten metal held at a low temperature in a molten metal furnace such as a holding furnace or a hand melting furnace by the casting apparatus according to claim 5, wherein the molten metal is heated in a supply line of the molten metal. A casting method in which the temperature is controlled to a high temperature and molten metal is injected into the mold.