JPH03199322A - Method and device for rapid melting and tapping by cold supply of aluminum ingot - Google Patents

Abstract

PURPOSE:To make induction coils to a single coil and to reduce the overall height of the device by using an upright hollow pipe-shape furnace which integrally connects a melting chamber and a heating up chamber via a duckboard- like flow regulating plate and using the annular gap between inside and outside furnaces as the tapping path for a molten metal. CONSTITUTION:The ingot of an Al metal is inserted into the melting chamber 14 as a coolant from the upper open end 12 of the inside furnace 2 for inserting and melting and is melted by a melting/heating up coil 18. The generated molten drops are dropped through the lower flow regulating plate 15 into the heating up chamber 17 and are put into the annular gap 4 between the inside furnace 2 and the outside furnace 3 disposed coaxially on the inside furnace 2 through the passage 11 of a block 6 which shuts off the inside of the inside furnace from the aperture at the bottom end of the outside furnace. A molten metal pool is formed and held in the gap 4 and is heated by the coil 18 during this time. The molten metal is risen up to the height exceeding a flange 9 and is tapped by an electromagnetic pump 19. The unnecessary remaining and slag, etc., are discharged from a discharge port 5.

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a method and device for rapidly melting and tapping aluminum or aluminum alloy (hereinafter abbreviated as aluminum-based metal) ingots, and more specifically, the present invention relates to a method and device for rapidly melting and tapping aluminum or aluminum alloy (hereinafter abbreviated as aluminum-based metal) ingots. When casting and forming parts for electrical equipment, etc., aluminum-based metal ingots (aluminum ingots) are placed immediately before the pouring slot of the die of a die-casting machine or the pouring hole of other casting equipment.
directly melting one or two of them by induction heating, so-called
Relates to a rapid melting method and device for melting by a cold material insertion melting method, flowing down into a temperature rising region to form °C molten metal, and transporting the heated molten metal upwards by an electromagnetic pump to pour it into the die of a die casting machine, etc. It is something. [Prior Art] Aluminum has the characteristics of low specific gravity and low melting point when used as structural members for general machinery, special machinery, vehicles, electrical equipment, etc. However, when made into an alloy, it has considerable strength. It is also widely used as wrought material and cast products. In addition to ordinary molds and sand castings, die castings, shell castings, centrifugal castings, etc. are also used for casting products. Among these, the die casting method uses a die casting machine (also called a die casting machine5) to melt the The metal is placed under high pressure in a tie mold called a die. Moreover, it is possible to make precision castings by repeating injection at high speed, which meets the requirements for dimensional accuracy and productivity, so it is being used more and more often. However, in general, in order to supply molten metal to a die-casting machine, as shown in Fig. 3, a large amount of molten metal is heated to 570 to 600°C by intensive melting in a melting furnace 31 using gas or heavy oil as a heat source. Holding furnace 3 that uses heavy oil as a heat source
2 and held for a long time, and then transferred to a hand furnace 34 by means of transportation such as a trolley 33, and is suitable for pouring.
Raise the temperature to 20℃ by one person or robot 351
'J: This follows the method of feeding into the die slot 37 of the die casting machine 36. [Problems to be Solved by the Invention] However, such a method involves a large-scale work process that uses multiple furnaces, so it requires a large factory space and requires long hours of work using multiple furnaces. Since the material is kept in a molten state and transported between multiple furnaces, the material yield is low due to losses such as combustion, oxidation, and scattering, and there is also a large amount of energy loss due to waste heat and heat radiation. It was uneconomical in terms of In addition, there were many steps involved in transporting, storing, and pumping out molten metal, resulting in low work efficiency, as well as concerns about safety and poor working conditions. Furthermore, since it takes a long time to heat up a large-capacity furnace to a predetermined temperature, there was a need for a solution to problems related to working conditions, such as the need for melting workers to be dispatched early. In order to solve the problems with the above-mentioned molten metal supply apparatus that uses a large-capacity melting furnace, intermediate holding furnace, hand furnace, etc., the inventor of the present invention has made an effort to transfer aluminum ingots to a die of a die-casting machine or other casting machine. The idea was to adopt a cold material rapid melting method in which the molten metal is melted directly just before the pouring port, heated to a predetermined pouring temperature, and then poured into the die, but in order to do so, the following points needed to be resolved. Ta. ■Structure of the heating energy heat source and melting chamber for cold material insertion and melting of aluminum ingots. ■Structure of a cold material supply device for inserting aluminum ingots into the melting chamber. ■Heating means and heating chamber structure for storing molten aluminum and raising the temperature to the specified pouring temperature. ■How to pour molten metal from the melting chamber to the heating chamber, and from the heating chamber to the pouring slot of the die. ■Ancillary equipment related to the above.

[Means to solve the problem]

In the present invention, in order to solve the above-mentioned problems regarding cold material insertion, melting, pouring, etc., the most important goal is to minimize the number of furnace bodies, induction heating coils, MM1 pumps, etc., and the following: We adopted a rapid melting and tapping method and equipment for aluminum ingots. First, I will explain the rapid melting tap device in detail.
This device consists of the following parts: (A) Melting of cold material in aluminum ingots, with an opening at the upper end that serves as an insertion port for the aluminum-based metal ingot, and an opening at the lower end that serves as the base of the outlet through which the heated molten metal flows outward in the radial direction. , an inner furnace body for melting and temperature raising as a metallurgical container for heating, and inserting the inner furnace at a position near the lower end of the inner furnace body, dividing the interior into a melting chamber and a heating chamber, and inserting the inner furnace. - An upright hollow cylindrical inner furnace with a drainboard-like baffle plate that allows the molten metal melted in the melting chamber to flow down. (B) an outer moat disposed coaxially outside the inner furnace and having an inner diameter sufficient to form an annular gap sufficient for the molten metal to pass through and flow between the inner furnace and the upper end thereof and the outer moat; An upright hollow cylindrical outer moat with a molten metal outlet communicating with the defined annular gap divided into two parts between the upper end of the inner furnace and an opening for discharging excess residual metal, slag, etc. at the lower end. (C) A part is inserted into the opening at the lower end of the inner furnace, and the remaining part protrudes toward the opening at the lower end of the outer furnace to close the opening at the lower end of the outer furnace, and normally the inside of the inner furnace and the lower end of the outer furnace The block has at least one molten metal passage for communicating between the inside of the inner furnace and the annular gap, while blocking the opening of the inner furnace. (D) An induction heating coil disposed around the outer moat to melt the cold material of the aluminum ingot in the insertion/melting chamber and to raise the temperature of the molten metal in the heating chamber to a predetermined pouring temperature. (E) is arranged below the induction heating coil on the outer periphery of the outer moat, and applies a thrust to the molten metal stored in the warming chamber and the annular gap communicating therewith and heated to a predetermined pouring temperature; and an electromagnetic pump for causing the metal to flow upward in the annular gap and pouring the metal out of the furnace from the tap. The inner furnace and the outer moat have flanges extending radially outward at their upper ends, the flange of the inner furnace is disposed at a higher position than the flange of the bamboo, and the upper and lower flanges are It is preferable that an annular tap passageway communicating with the annular gap and leading to the tap opening is formed between the two. Note that it is convenient if the inner furnace consists of two parts, an upper and a lower part, and these parts are connected together by a spigot joint. Further, it is preferable that the block is connected to the lower end of the inner furnace via a ring made of metal such as cast iron. Next, the rapid melting and tapping method of the present invention will be explained below. (a) Insert an aluminum ingot as a cold material into the melting chamber of the inner furnace for insertion and melting, and proceed with melting while forming droplets from the surface to the inside. (b) The formed droplets are allowed to flow down into the heating chamber and further into an annular gap defined between the inner furnace and the bamboos and communicating with the lower end of the inner furnace to form a molten metal pool. (c) The aluminum ingot being melted is heated by induction heating using a melting/heating coil, and if the length of the aluminum ingot being melted decreases to less than a predetermined length due to melting, the next aluminum ingot is inserted to replenish the aluminum ingot. (d) When the molten metal in the molten metal pool reaches a predetermined temperature, the electromagnetic pump is energized to transport the molten metal in the heating chamber and the annular gap upwardly through the tap opening. It is convenient to insert two aluminum ingots into the melting chamber with their flat bottoms in contact with each other and placed back to back. [Function] It has a double tube structure between the inner furnace and bamboo, and the two are communicated through a molten metal passage opened at the bottom of the block, but there is an opening that allows the molten metal to naturally flow outside due to gravity. Therefore, the molten metal can be held in the furnace without operating the electromagnetic pump during temperature rise. While the molten metal is stored in the heating chamber of the inner furnace and the annular gap between the inner furnace and the outer furnace in a communicating state, it is heated by magnetic flux from an induction coil for melting and heating linked to the molten metal. The temperature is raised to the hot water temperature. The hollow straight pipe-shaped inner furnace for melting and heating can be set in advance in the outer furnace as a cassette-type inner furnace, or can be removed. The chamber is made in two parts and joined by a dowel joint, allowing each part to be replaced separately in case of damage. The thus joined inner furnace body has an outer flange,
The interior consists of two parts: an insertion/melting chamber from the top, which serves as an insertion port for aluminum ingots, to an intermediate rectifier plate, and a warming chamber, which extends from the rectifier plate to the bottom end, which serves as an outlet for the molten metal. Embodiment 1 FIG. 1 is a side sectional view showing a preferred embodiment of the rapid melting and tapping device of the present invention. In Fig. 1, 1 indicates the entire rapid melting tap device, and 2
3 is the melting/heating/pouring furnace (inner furnace) body, and 3 is the annular gap 4 into which the inner furnace body 2 is inserted and set for heating/pouring.
The device is made of bamboo for controlling images, and the device as a whole has a hollow, right cylindrical double-tube structure. The bamboo 3 is arranged as an upright cylindrical tube with a bottom that can accommodate the inner furnace 2 while maintaining a sufficient annular space 4. The bamboo 3 has a flange 9 projecting outward at the upper opening surface and a flange 9 at the center of the bottom surface. A discharge hole 5 is provided. When setting in a so-called cassette type, a right cylindrical block 6 made of a refractory material is attached to the lower end of the outer furnace 2 through a ring 7 made of metal such as cast iron attached to the lower end of the inner furnace 2 for reinforcement. If it is inserted into the opening so that it is seated, it will be centered and connected. A molten metal passage 11 communicating with the annular gap 4 is provided in this right circular cylinder block 6 from its upper surface toward the side surface obliquely downward. When the inner furnace 2 is set on the bamboos 3, the annular gap 4 formed between the outer wall of the inner furnace 2 and the inner wall of the bamboos 3 is used as a tap passage when the molten metal is reversely spouted upward. . The inner furnace 2 serves as an insertion point for aluminum ingots as a cold material, and has a relatively long hollow right cylindrical shape extending from an upper open end 12 having a flange 8 extending outward in the radial direction to a straightening plate 15 for insertion and melting. A heating chamber 17 extending from the current plate 15 to a lower end 16 that serves as a discharge outlet for residual hot water and slag, and a sealing stopper portion consisting of a metal ring 7 and a cylindrical block 6. Consists of parts. On the outer periphery of the outer moat 3, a melting/heating coil 18 is installed at a portion corresponding to the range from the insertion/melting chamber 14 of the inner furnace 2 to the upper part of the warming chamber 17, and below that, to the lower end of the outer moat 3. Electromagnetic pumps 19 for injecting molten metal are respectively arranged on the outer periphery of the outer moat 3 corresponding to the molten metal. The heating chamber 17 of the inner furnace 2 and the annular gap 4 that communicates with it become a molten metal pool, and the heating and pouring area with a pouring port at 6 and the insertion and melting chamber 14 serve as a molten metal pool for inserting and melting aluminum ingots. This becomes the insertion/dissolution zone that also serves as temperature rise. The temperature raising/molten metal pouring area and the insertion/melting area are separated by a drainboard-shaped rectifier plate 15 located between the two and having a large number of slots. This rectifying plate 15 prevents the aluminum ingot inserted from the upper open end 12 from falling to the heating chamber 17 due to gravity, and restrains the aluminum ingot in the insertion/melting chamber 14, and also uses induction heating to prevent the aluminum ingot from falling into the warming chamber 17 due to gravity. Aluminum droplets that melt and drip from the surface of the aluminum ingot while being heated pass through slots and flow into the heating chamber 17 to form and hold a molten metal pool. Next, the operating method of the above embodiment will be described. In addition, the normal operation process of heating up and pouring molten metal involves two processes: an outer moat and an inner furnace.
It is repeated with two hollow straight pipe sections arranged together upright. (1) Aluminum ingots are not standardized and their shape and dimensions are not specified, but usually the bottom surface 21 is almost flat and the top surface 22 has a V- or U-shaped groove 2.
Two to three trapezoidal convex portions 24 partitioned by 3 are formed. Then, as shown in Fig. 2 CB), the flat bottom surfaces 21 of the two aluminum ingots 20 are placed back to back to form a pair, and the U-shape on the surfaces 22 on both left and right sides is used as a unit of l during transportation and melting. Using the groove 23 that engages the claw of a gripping member of a cold material supply device (not shown), the cold material is conveyed by the cold material conveying device to the upper open end 12 shown in FIG. 1, and inserted and melted from the upper open end 12. Insert into chamber 14. (2) Electrify the melting/heating coil 18 and insert/melting chamber 1
The aluminum ingot No. 4 is melted as droplets from its surface by induction heating. The thus generated droplets pass through the lower baffle plate 15, drop into the heating chamber 17, pass through the molten metal passage 11, flow into the annular gap 4, form a molten metal pool, and are held there. The temperature is raised to a predetermined pouring temperature by induction heating by the heating coil 18. (3) When the predetermined temperature of the hot water is reached, the electromagnetic pump 19 is energized to pump the molten metal from the bottom of the annular gap 4 to the flange 9 of the outer moat 3.
to rise against gravity to a height exceeding . Thus,
The molten metal in the heating chamber 17 passes through the molten metal passage 11 and is injected outward in the radial direction, hits the inner bottom of the furnace wall of the outer moat 3, and the flow direction is changed upward, and the molten metal in the annular gap 4 and the outer moat 3 are injected. The molten metal rises to a height exceeding the flange 9 and is poured into the die-casting machine's goose slot. (4) When discharging unnecessary residual metal or slag, or when discharging unnecessary residual metal or slag, etc. When repairing the inner wall of the outer moat 3, etc., take out the cassette-type inner furnace 2 from the outer moat 3, remove the block 6 made of refractory material that closes the discharge port 5, and remove it from the slag storage area or repair yard. Drop it onto a surface and eject it. (5) When replacing the entire inner furnace 2, the damaged inner furnace 2 is taken out from the outer moat 3, repaired or discarded, and another inner furnace is inserted into the outer furnace 3. Note that if the inner furnace 2 is composed of two parts, an upper and a lower part, which are connected by a spigot joint, it is also possible to separate and replace them individually. [Effect 1] As understood from the above explanation, the aluminum ingot is inserted just before the die-casting machine's die slot and melted.
In carrying out so-called cold insertion melting, the apparatus of the present invention achieves many advantages in terms of construction and operation. (b) As a furnace for melting and raising the temperature of aluminum ingots, an upright hollow tubular inner furnace is adopted in which the melting chamber and heating chamber are connected to each other with a drainboard-like rectifying plate interposed therebetween, and the furnace is cooled from the upper opening. An aluminum ingot is inserted as a material, and in the melting zone, the aluminum ingot is melted sequentially from the surface and flows down to the temperature raising zone as a large number of droplets, and the temperature is raised until it reaches the pouring temperature. Uses a single induction coil. Since melting and temperature raising can be performed using a single inner furnace and a single induction heating coil in this way, the structure is simple and manufacturing costs are low. (b) The annular gap between the outer moat and the inner furnace is used as a path for tapping the heated molten metal, and the flow of the molten metal is reversed upward by an electromagnetic pump, so the height of the annular gap is equivalent to the height of the entire device. The height can be reduced and it can be installed in a relatively low factory building. (c) If the inner furnace for melting and temperature raising can be attached and detached from the outer moat in a cassette style, and if the inner furnace itself can be separated into upper and lower parts and connected to each other by inlay, each can be manufactured and stored separately. death,
It can also be repaired or replaced. C2) When raising the temperature of the molten metal, there is no need to use an electromagnetic pump to hold the molten metal in a temperature rising region against gravity, so there is no fear of the molten metal spouting out during a power outage.

[Brief explanation of drawings]

Figure 1 is a side sectional view showing an embodiment of the present invention, Figure 2 (A
) is a perspective view showing a typical shape of an aluminum ingot, Figure 2 (B) is a side view showing a pair of two aluminum ingots, and Figure 3 is a schematic diagram showing the conventional melting and pouring method. Figure 1. Code l in the drawing: rapid melting tap device, 2: inner furnace, 3: outer moat, 4: annular gap, 5: discharge port,
6: Block, 7: Metal ring, 8
．． 9: Flange, ll: Molten metal passage, 12: Upper open end, 14: Insertion/melting chamber 15: Current plate, 16:
Lower end of inner furnace 17: Warming chamber, 18: Melting/heating coil, 19: Electromagnetic pump, 20 Ni aluminum ingot, 21:
flat bottom. Chapter Il! !

Claims (1)

[Claims] 1. When pouring molten aluminum-based metal containing aluminum and its alloys into a casting machine such as a die-casting machine,
This rapid melting and tapping device supplies an aluminum ingot with a composition corresponding to the molten metal as a cold material at a position close to the casting machine, rapidly melts the aluminum ingot to form the molten metal, raises the temperature, and pours the aluminum ingot as a cold material. It has an opening at the upper end that serves as an insertion port for the aluminum-based metal ingot, and an opening at the lower end that serves as the base of the outlet through which the heated molten metal flows outward in the radial direction, and melts the cold material of the aluminum ingot. An inner furnace body is used for melting and temperature raising as a metallurgical container for heating, and the inner furnace is inserted near the lower end of the inner furnace body.The interior of the inner furnace is divided into a melting chamber and a heating chamber, and an upright hollow cylindrical inner furnace having a drainboard-like baffle plate that allows the molten metal melted in the melting chamber to pass and flow; an outer furnace having an inner diameter sufficient to form an annular gap sufficient for the molten metal to pass through and flow between the outer furnace and the upper end of the inner furnace, the molten metal communicating with the defined annular gap between the upper end of the outer furnace and the upper end of the inner furnace; an upright hollow cylindrical outer furnace with a defined outlet and an opening at the lower end for discharging excess residual metal, slag, etc., a part of which is inserted into the opening at the lower end of the inner furnace, and the rest of the furnace The opening at the lower end of the outer furnace protrudes toward the opening at the lower end of the outer furnace to close the opening at the lower end of the outer furnace and normally blocks the inside of the inner furnace and the opening at the lower end of the outer furnace. a block having at least one molten metal passage for communicating with the outer furnace; and a block disposed around the outer periphery of the outer furnace to melt the cold material of the aluminum ingot in the insertion/melting chamber, and to pour the molten metal in the heating chamber into a predetermined amount. an induction heating coil that raises the temperature of the hot water to a predetermined pouring temperature; An electromagnetic pump for applying a thrust to the heated molten metal to cause it to flow upward in the annular gap and pouring the molten metal out of the furnace from the tap outlet. Rapid melting tap device by supply. 2. The inner furnace and the outer furnace each have a flange extending radially outward at their upper ends, and the flange of the inner furnace is located at a higher position than the flange of the outer furnace, and there is a space between the upper and lower flanges. 2. The rapid melting and tapping device for aluminum ingots as claimed in claim 1, wherein an annular tapping path communicating with the annular gap and leading to the tapping port is formed. 3. The rapid melting and tapping apparatus for aluminum ingots by supplying cold material according to claim 1 or 2, wherein the inner furnace consists of two parts, upper and lower, which are integrally connected by a spigot joint. 4. Rapid melting of an aluminum ingot by supplying cold material according to any one of claims 1 to 3, wherein the block is connected to the lower end of the inner furnace via a ring made of metal such as cast iron. Hot water supply device. 5. A rapid melting and tapping method by supplying a cold material from an aluminum ingot, which rapidly melts the aluminum ingot into molten metal, raises the temperature, and then pours the aluminum ingot, which is an inner furnace for inserting and melting the aluminum ingot as a cold material The melting chamber is inserted into the melting chamber, and the melting proceeds while forming droplets from the surface to the inside, and the formed droplets flow down into the heating chamber. The molten metal also flows into the annular gap communicating with the lower end of the inner furnace to form a pool, and is heated by induction heating by the melting and heating coil to raise the temperature. During this time, the aluminum ingot being melted is melted to a specified length or less. If the amount decreases, the next aluminum ingot is inserted to replenish the pool, and when the molten metal in the molten metal pool reaches a predetermined temperature, the electromagnetic pump is energized to move the molten metal in the heating chamber and the annular gap through the annular gap. A method for rapidly melting and tapping an aluminum ingot by supplying cold material, which is characterized by transporting the aluminum ingot upward and tapping it from a tap opening. 6. The aluminum ingot according to claim 5, wherein the aluminum ingots are inserted into the melting chamber in a set of two, with their flat bottoms in contact with each other and back to back. Rapid melting and tapping method using cold material supply.