JPH03199326A - Method and device for rapid melting of aluminum ingot - Google Patents

Abstract

PURPOSE:To lessen a factory space and energy loss and to improve a material yield by receiving ingots, transporting the ingots to the insertion point of an insertion guide above a melting furnace, inserting the ingots into a melting furnace 0, melting the ingots, and allowing the molten metal to flow down into a heating up furnace proximate to the melting furnace. CONSTITUTION:One or more pieces of Al ingots are transported as cold bodies up to the cold body insertion guide 11 by a cold body supplying device 19 and are inserted into the guide 11, from which the ingots are inserted by gravity into the melting furnace 12. An induction coil disposed on the outer periphery of the melting furnace 12 is energized in an induction coil and the ingots inserted into the melting furnace 12 are inductively heated. The molten drops generated by this operation transfer on the surface of the ingots and flow into the heating up furnace 14 through the outflow port in the lower part of the melting furnace 12. The molten drops further pass the outflow port in the lower part thereof and flow into a tapping pipe. The purpose is achieved by this method and the exact temp. control is executed.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a rapid melting device for aluminum or aluminum alloy (hereinafter referred to as aluminum-based metal) ingot, and more specifically, to a device for rapidly melting aluminum or aluminum alloy (hereinafter referred to as aluminum-based metal) ingot. When molding by casting into parts for machines, electrical equipment, etc., aluminum-based metal ingots (hereinafter abbreviated as aluminum ingots) are formed immediately before the pouring slot of the die of each die-casting machine or the pouring port of other casting equipment. 0) Melt 1 to 2 pieces directly by induction heating, etc., using the so-called cold material insertion melting method,
While thinking about the technology for the rapid melting of aluminum ingots, in which the molten metal is made to flow down into a temperature rising region, heated to a predetermined temperature on the spot, and poured into the die of a die-casting machine, the basic concept was developed. This invention relates to a method and apparatus for rapid melting using a cold material supply as a basic prototype. [Prior Art] Aluminum has the characteristics of low specific gravity and low melting point, and can be used as a structural member for general machinery, special models, vehicles, electrical equipment, etc., and when made into an alloy, it can be made to have considerable strength. It is widely used as wrought material and cast products because of its ability to In addition to regular molds and sand castings, die castings, shell castings, centrifugal castings, etc. are used for casting products. Among these, the die casting method uses a die casting machine (referred to as a die casting machine6) to melt the It is possible to repeatedly inject metal into a mold called a die under high pressure and at high speed to create a precision cast product, which meets the requirements for 1-dimensional accuracy and productivity, so demand has been increasing in recent years. are doing. 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 there for a long time, and then transferred to a hand furnace 34 by means of transportation such as a trolley 33, heated to a temperature suitable for pouring, for example, 720°C, and die-cast by hand or by a robot 35. die slot 37 of machine 36
The method follows the method of supplying the product inside. [Problems to be solved by the invention] However, this method is large-scale and uses a work process that passes through many furnaces, so it requires a large factory space and requires long-term work using multiple furnaces. In order to keep it in a molten state for a long time and transport it between multiple furnaces,
In addition to the drawback of low material yield due to losses such as combustion, oxidation, and scattering of materials, there was also a large amount of energy loss due to exhaust heat, heat radiation, etc., making it uneconomical from a physical standpoint. In particular, melting furnaces and holding furnaces that supply molten metal used in a large number of casting machines in a foundry have to be maintained at high temperatures for long periods of time. In addition, there are many processes such as transporting, storing, and pumping out molten metal, which lowers work efficiency. In addition, there are many maintenance steps, safety concerns, and the need to raise the temperature of a large-capacity furnace to a predetermined temperature. Due to the long start-up time, it was necessary to bring out melting tools early or overtime, and other problems related to working conditions6, which were requested to be resolved. The inventor of the present invention aimed to solve many problems with the above-mentioned molten metal supply methods and devices that use large-capacity melting furnaces, intermediate holding furnaces, hand furnaces, etc. We developed the concept of using a cold material rapid melting method, in which the molten metal is melted directly just before the pouring port of a die loft or other casting machine, heated to a predetermined pouring temperature, and then poured into the die. To do so, it was necessary to solve the following issues. ■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 to house the aluminum melt and raise 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 tie pouring slot. [Means for Solving the Problems] In order to solve the above-mentioned problems related to cold material insertion, melting, temperature rise, tapping, etc., the present invention provides the following aluminum ingot rapid melting method and apparatus. Adopted. First, the rapid dissolution method of the present invention will be explained below. (b) Receive at least one aluminum ingot as a unit, transport it to the cold material insertion point of the cold material insertion guide located vertically above the insertion area of the melting furnace that has the insertion opening, and Insert into the melting furnace. (b) The inserted aluminum ingot is melted from its surface in the melting furnace and allowed to flow down as droplets. (c) Direct the falling droplets to the NU in the vertical F direction of the melting furnace.
When the molten metal is housed in a storage area that includes a furnace and a tapping pipe that communicates with the lower part of the furnace, the molten metal is heated and raised to a temperature suitable for tapping into the spout of casting equipment such as a die-casting machine. do. (d) Tapping a predetermined amount of molten metal heated to a predetermined temperature. The aluminum ingots are stacked in units of two pairs, with their flat bottoms facing inwards, their tops concave outwards, and their protrusions facing the opposite sides. It is convenient to transport one unit of the aluminum ingot from the outer ml of the aluminum ingot by using one of the pairs of grooves formed on both outside sides by the recesses described in 11ii. In addition, in principle, melting the aluminum ingot in the melting furnace and raising the temperature of the molten metal in the temperature raising furnace are performed by heating with induction coils placed around the outer periphery of each furnace, and the molten metal is tapped. Star adjustment is performed by the 'Iim pump. The rapid dissolution device of the present invention is composed of the following parts. (A) A container for storing at least 61 aluminum ingots to be supplied as a cold material and sequentially melting them into droplets from the outer periphery, with an opening at the top for inserting the aluminum ingots. An upright hollow cylindrical melting furnace having a heating device for melting the aluminum ingot on the outer periphery and an outlet at the bottom through which droplets generated by melting flow down. (B) Proximity to the lower part of the melting furnace, with an opening at the top through which the droplets generated in the melting furnace pass, and raising the temperature of the molten metal formed by the accumulation of the droplets to a predetermined temperature. This is an upright hollow cylindrical heating furnace that has a heating device on its outer periphery and an outlet at the bottom that allows the molten metal inside to flow further downward. (C) An outlet for tapping the heated molten metal, which surrounds the outlet of the temperature raising furnace, extends further downward in close contact with the bottom, and has an opening for communicating with the temperature raising furnace at the upper end. An upright hollow cylindrical tapping pipe with a sprue at the bottom of the side wall and a thrust applying device on the outer periphery that applies thrust to the molten metal in order to adjust the tapping position of the heated molten metal. The heating furnace and the tapping pipe constitute an integral molten metal storage container that communicates with each other. Note that it is preferable that the heating devices provided on the outer periphery of the melting furnace and the temperature rising furnace be induction coils, and the thrust applying device provided on the outer periphery of the tapping pipe be an electromagnetic pump. [Function] The aluminum ingot is melted from the surface in the melting furnace to form droplets, which flow down from the outlet of the melting furnace into the heating furnace to become molten metal, and further flow into the tap pipe. If a thrusting device such as an electromagnetic pump is not installed, when the level of the molten metal flowing into the tap pipe exceeds the tap near the bottom end of the tap, the molten metal will begin to flow out due to gravity.
In the present invention, since a thrust applying device is arranged on the outer periphery of the tapping pipe, this thrust applying device is operated to cause the molten metal to flow out from the tapping port due to gravity in the opposite direction to that in the case of tapping the molten metal. If you give enough thrust to stop the
The molten metal flows out from the tapping port 11 <The molten metal is retained as a molten boule in the heating furnace and tapping pipe, and in this state, the molten metal is heated to a predetermined temperature in the heating furnace. Then, once the temperature has been raised to a predetermined temperature, a downward thrust is applied to the molten metal by the thrust applying device. Alternatively, if the thrust applying device is stopped, a predetermined amount of molten metal can be tapped from the tap. [Example] Next, an example of the present invention will be described with reference to FIGS. 1(A) and 1(B). FIG. 1(A) is a side sectional view showing a rapid melting device of the present invention, and FIG. 1(B) is a side view showing the overall arrangement of the melting device. In these figures, reference numeral 10 indicates the entire rapid melting device, and reference numeral 11 indicates a cold material insertion guide serving as a guide for inserting the cold material, which guides and melts the cold material 20 of the aluminum ingot sent by the cold material supply device 19. While inserting into the furnace 12, the melting furnace 12
This prevents droplets of the aluminum ingot melted within the melting furnace 12 from scattering outside the melting furnace 12. Aluminum ingots are non-standard and have no defined shape or dimensions, but usually the bottom surface 21 is almost flat and the top surface 22 is partitioned with a ■ or U-shaped groove 23, as shown in Figure 2 (A). Two to three trapezoidal convex portions 24 are formed. As shown in FIG. 2(B), the flat bottom surfaces 21 of the two aluminum ingots 20 are placed back to back to form a pair, and are used as one unit during transportation and melting.
The U-shaped groove 23 of 2-H is used as a groove in which the claw of the gripping member of the cold material supply device 19 is engaged. The melting furnace 12 is a hollow cylindrical furnace made of refractory material and has an upright eave.The internal space houses a cold aluminum ingot, and an induction coil 13 installed on the outer periphery heats the aluminum ingot from its surface to form droplets. Dissolve to form. Further, an outlet 12a is formed in the bottom wall of the melting furnace 12 and extends downward in the axial direction, and the aluminum droplets flow downward from the outlet 12a. Reference numeral 14 denotes a heating furnace disposed coaxially below the melting furnace 12. It is an upright hollow cylinder with an eave made of refractory material and has almost the same shape as the melting furnace 12. Like the melting furnace 12, the bottom wall has a bottom wall. An outflow port 14a is opened, and the molten metal inside is heated by an induction coil 15 provided on the outer periphery to a temperature, for example, 720° C., for discharging the molten metal into a goo of a casting device such as a die-casting machine 18. Furthermore, a hollow tubular tapping pipe 16 is provided at the bottom of the heating furnace 14, surrounding the outlet 14a from the outside, extending downward, communicating with the heating furnace 14, and serving as an extension thereof. The hot water tapping pipe 16 is an elongated hollow tube with a bottom closed at the lower end, and a hot water tap 16a for tapping the hot water into the die-casting machine 18 or the like is located near the bottom of the side wall. An electromagnetic pump 17 for applying thrust to the molten metal is attached to the side wall of the tap pipe 16 above the tap port 16a. Next, the operating method of the present invention will be described. (1) Aluminum ingots are conveyed one pair at a time to above the lubricant insertion guide 11 by the cold material supply device 19. This cold material supply device N19 is inserted into the cold material insertion guide 11 using an air cylinder (not shown), etc., and is moved into the melting furnace 12 by gravity.
Insert inside. Note that when the already inserted aluminum ingots are in the melting furnace 12, the timing to insert the next pair of aluminum ingots is determined when the height of the already inserted aluminum ingots in the melting furnace 12 increases as the melting progresses. The induction coil 13 is successively lowered and when the next pair of aluminum ingots is inserted.
The magnetic flux from the quib is adjusted so that the linkage line becomes the optimal state for melting the aluminum ingot of that quib, that is, the optimum melting linkage point. (2) The induction coil 13 is energized and the aluminum ingot inserted into the melting furnace 12 is heated by induction.9 The droplets generated by this operation travel along the surface of the aluminum ingot and pass through the outlet 12a of the melting furnace 12. The molten metal flows into the furnace 14, passes through the outlet 14a, and flows into the outlet pipe 16. (3) At the same time as in (2) above, the electromagnetic pump 17 is given a thrust in the opposite direction to the tapping direction, that is, upward against the molten metal so that the molten metal does not flow out from the tap outlet 16a due to the action of gravity. (4) Electricity is supplied to the temperature raising 51 illumination 15 to raise the temperature of the molten metal in the temperature raising furnace 14 to a predetermined temperature. (5) Once the temperature has risen to a predetermined pouring temperature, either apply thrust to the magnetic pump 111 in the tapping direction, that is, the molten metal number, or stop the electromagnetic pump 17 to pour the molten metal in a predetermined amount at the tap outlet. Molten metal is poured into the die-casting machine 18's guide slot etc. from 16a. [Effect of the invention] As can be understood from the above explanation, an aluminum ingot is inserted and melted just before the die-casting machine's die slot.
When performing so-called cold material insertion melting, if the method and apparatus of the present invention is used, the temperature of the melting material can be raised using independent melting furnaces and temperature raising furnaces, which are arranged close to each other above and below. Accurate temperature control is possible because induction coils are placed in each location. In addition, the heating furnace and the tapping pipe communicate with each other through the outlet, and the molten metal inside them is heated to the optimum temperature by the heating coil as a whole, and is tapped out by the electromagnetic pump on the outer periphery of the tapping pipe. The amount and speed of hot water can be precisely controlled.

[Brief explanation of drawings]

FIG. 1(A) is a side sectional view showing a rapid melting apparatus for aluminum ingots according to the present invention, and FIG. 1(B) is a side view showing the arrangement relationship of the rapid melting apparatus shown in FIG. 1(A) and related devices. ,
FIG. 2(A) is a perspective view showing a typical aluminum ingot, FIG. 2(B) is a side view showing a state in which the two aluminum ingots shown in FIG. 2(A) are pressed together, FIG. 3 is a schematic diagram showing the conventional melting and pouring method. 16a: Tap spout, 17: Electromagnetic pump, 18: Die casting machine, 20mm aluminum ingot. 21: Bottom, 23: U”f$ full.

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,
In this rapid melting method, an aluminum ingot having a composition corresponding to the molten metal is supplied as a cold material at a position close to the casting machine, rapidly melted to form a molten metal, heated, and poured. Then, at least one of the aluminum ingots is received as a unit, and transported to a cold material insertion point of a cold material insertion guide arranged vertically above an insertion area having an insertion opening of the melting furnace, and this aluminum ingot is The aluminum ingot is inserted into the melting furnace, and the inserted aluminum ingot is melted from its surface in the melting furnace and flows down as droplets, and the flowing droplets are transferred to a heating furnace located vertically below the melting furnace. The molten metal is stored in the molten metal storage section that includes a tap pipe communicating with the lower part of the molten metal, and is heated to a temperature suitable for tapping into the pouring hole of casting equipment such as a die-casting machine. A method for rapidly melting aluminum ingots, which is characterized by tapping molten metal. 2. Aluminum ingots are made into a pair of two.
The flat bottoms of the flat bottoms are placed back to back on the inside, the tops are concave on the outside, and the convex portions are stacked in corresponding positions on the opposite side to form one unit, and the concave portions are formed on both outside sides by the concave portions. 2. The method for rapidly melting an aluminum ingot according to claim 1, wherein one of the pairs of grooves is gripped from the outside of the aluminum ingot and conveyed. 3. Melting the aluminum ingot in the melting furnace and raising the temperature of the molten metal in the heating furnace are performed by heating using induction coils placed around the outer periphery of each furnace, and the amount of molten metal coming out is controlled by electromagnetic heating. Claim 1 or 2 carried out by a pump
A method for rapidly melting aluminum ingots as described in . 4. Receive aluminum ingot cold material to make molten metal to be poured into casting machines such as die casting machines, rapidly melt it to make molten metal,
An apparatus for rapidly melting aluminum ingots by raising the temperature and pouring molten metal into the aluminum ingots, the apparatus comprising:
As a container for accommodating aluminum ingots and sequentially melting them from the outer periphery to form droplets, the opening for inserting the aluminum ingot is installed at the top, and the heating device for melting the aluminum ingot is installed at the outer periphery. an upright hollow cylindrical melting furnace having an outlet at the bottom through which the droplets generated by the melting furnace flow; An upright hollow cylindrical shape having a heating device on the top for raising the temperature of the molten metal formed by the accumulation of the droplets to a predetermined temperature on the outer periphery, and an outlet at the bottom for allowing the molten metal inside to flow further downward. A heating furnace,
an opening that surrounds the outlet of the heating furnace, extends further downward in close contact with the bottom, and has an opening at the upper end for communication with the heating furnace;
An upright hollow cylindrical tapping pipe having a tapping port for tapping the heated molten metal at the bottom of the side wall and a thrust applying device on the outer periphery for applying thrust to the molten metal to adjust the amount of heated molten metal coming out. An apparatus for rapidly melting aluminum ingots, characterized in that the heating furnace and the tapping pipe constitute an integral molten metal storage container that communicates with each other. 5. Rapid melting of an aluminum ingot according to claim 4, wherein the heating device provided on the outer periphery of the melting furnace and the outer periphery of the temperature raising furnace is an induction coil, and the thrust applying device provided on the outer periphery of the tapping pipe is an electromagnetic pump. Device.