Holding furnace for die casting alloy

Abstract

The present invention relates to a holding furnace capable of producing reduced carbon emissions and having improved energy efficiency compared to the prior art by supplying molten metal of a die casting alloy for injection into a die casting apparatus. A holding furnace for a die casting alloy according to the present invention comprises: a first heat-retaining part made of a material comprising a refractory material and having a first space formed therein for accommodating, in a manner isolated from the outside, molten metal of an alloy that is to be die cast; and a second heat-retaining part formed on one side of the first heat-retaining part, made of a material comprising a refractory material, in communication with the first space, and having a second space formed therein that is isolated from the outside, wherein a first heating means for heating the molten metal using fossil fuel is disposed in the first heat-retaining part, a second heating means for heating the molten metal using electrical resistance heat is disposed in the second heat-retaining part, and a discharge port for discharging the molten metal to the outside is formed on the other side of the first heat-retaining part.

Description

Holding furnace for die-casting alloys

[0001] This invention was supported by the following national research and development project.

[0002] [Project ID] 2410002626

[0003] [Assignment No.] 00442070

[0004] [Ministry Name] Ministry of Trade, Industry and Energy

[0005] [Project Management Agency] Korea Institute for Industrial Technology Promotion

[0006] [Research Project Title] Development of LCA-based Carbon Emission Evaluation Method for Eco-friendly Automotive Materials and Components and Manufacturing Technology for Aluminum Die-casting Parts Achieving Over 25% Carbon Emission Reduction through the Use of Low-Carbon Materials and Processes

[0007] [Project ID] 2410004326

[0008] [Assignment No.] 20015347

[0009] [Ministry Name] Ministry of Trade, Industry and Energy

[0010] [Project Management (Specialized) Agency Name] Korea Institute of Industrial Technology Planning and Evaluation

[0011] [Research Project Title] Development of Die-casting Alloys and Parts for Forming Electric Vehicle Bodies and Chassis Using High-Manganese Steel Scrap

[0012] [Project ID] 1415190004

[0013] [Assignment No.] P0025666

[0014] [Ministry Name] Ministry of Trade, Industry and Energy

[0015] [Name of Project Management (Specialized) Agency] Korea Institute for Industrial Technology Promotion

[0016] [Research Project Title] Development of Die-casting Parts Applying Zero-Leak Tubes with High Heat Dissipation and High Airtightness for Optimized Thermal Management in Eco-friendly Electric Vehicles

[0017]

[0018] The present invention relates to a holding furnace for supplying molten die-casting alloy to be injected into a die-casting device, and more specifically, to a holding furnace capable of reducing carbon emissions and increasing energy efficiency compared to conventional furnaces.

[0019]

[0020] In the die-casting process, typically, the die-casting alloy is melted in a central melting furnace to produce a molten metal, which is then transported to a holding furnace located next to the die-casting device and injected into the die-casting device for forming.

[0021] A holding furnace for such die-casting alloys generally comprises an outer casing containing an insulating material and a heat-resistant material to prevent heat loss, an inner crucible containing high-temperature molten metal, a heating system that uses electricity or fossil fuels to maintain the molten die-casting alloy at a predetermined temperature, and a temperature control system that monitors the temperature of the molten metal and controls the heating element according to a set value.

[0022] The heating systems used in these furnaces utilize either fossil fuels, such as gas or diesel, or electricity as a heat source; however, using fossil fuels results in high carbon emissions, while using electricity leads to high energy costs.

[0023]

[0024] The objective of the present invention is to provide a holding furnace for die-casting alloys that can increase energy efficiency while reducing carbon emissions.

[0025]

[0026] As a means to solve the above problem, the present invention provides a holding furnace for die-casting alloys of (1) to (5) below.

[0027] (1) A first heat-retaining section formed with a first space that is enclosed from the outside and contains a molten alloy to be die-cast, made of a material containing a refractory material, and a second heat-retaining section formed on one side of the first heat-retaining section, made of a material containing a refractory material, connected to the first space, and has a second space enclosed from the outside, wherein a first heating means is disposed in the first heat-retaining section to heat the molten alloy using fossil fuel, and a second heating means is disposed in the second heat-retaining section to heat the molten alloy using electric resistance heat, and an outlet is formed on the other side of the first heat-retaining section to discharge the molten alloy to the outside.

[0028] (2) In (1), the first heating means is a burner arranged at a predetermined interval on the upper part of the first heat retention section, a heat retention furnace for die-casting alloys.

[0029] (3) In (1) or (2), the second heating means is used by being immersed in the molten metal and is a heating furnace for die-casting alloys, having a structure comprising a high-temperature metal heating element that is linear and generates resistance heat by applying an electric current, a heat conductor that is arranged in a manner that embeds the high-temperature metal heating element, and a ceramic coating that covers the outer side of the heat conductor.

[0030] (4) In (3), the high-temperature metal heating element comprises tungsten, the heat conductor comprises one or more selected from magnesium oxide (MgO), alumina (Al2O3), boron nitride (BN), and aluminum nitride (AlN), and the ceramic coating comprises Si3N4, a holding furnace for die-casting alloys.

[0031] (5) In (3), the above electric heaters are arranged in 2 or more places, forming a holding furnace for die-casting alloy.

[0032]

[0033] A holding furnace for die-casting alloys according to the present invention can reduce carbon emissions compared to a holding furnace using only fossil fuels by having a first holding section equipped with a first heating means using fossil fuels and a second holding section equipped with a second heating means using electric energy.

[0034] In addition, according to one embodiment of the present invention, improved energy efficiency can be obtained through an electric heater having improved efficiency compared to conventional ones.

[0035] The effects of the present invention are not limited to those mentioned above, and other unmentioned effects will be clearly understood by a person skilled in the art from the description below.

[0036]

[0037] FIG. 1 is a side cross-sectional view of a holding furnace for die-casting alloys according to one embodiment of the present invention.

[0038] FIG. 2 is a planar cross-sectional view of a holding furnace for die-casting alloys according to one embodiment of the present invention.

[0039] FIG. 3 schematically shows the structure of an electric heater provided in a holding furnace for die-casting alloys according to one embodiment of the present invention.

[0040]

[0041] Embodiments of the present invention are described below with reference to the attached drawings so that those skilled in the art can easily implement them. However, the present invention may be embodied in various different forms and is not limited to the embodiments described herein.

[0042] In addition, to clearly explain the present invention in the drawings, parts unrelated to the explanation have been omitted, and similar parts throughout the specification have been given similar reference numerals.

[0043] Throughout this specification, when a part is described as "comprising" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components.

[0044] Terms of degree used in this specification, such as “about,” “substantially,” etc., are used to mean at or near the stated value when inherent manufacturing and material tolerances are presented in the stated meaning, and are used to prevent unscrupulous infringers from unfairly exploiting the disclosure in which precise or absolute values ​​are mentioned to aid in understanding the invention.

[0045] Throughout this specification, the term “combination thereof” included in a Markush-style expression means one or more mixtures or combinations selected from the group consisting of components described in the Markush-style expression, and means including one or more selected from the group consisting of said components. Throughout this specification, the description “A and / or B” means “A or B, or A and B”.

[0046]

[0047] [Example]

[0048] FIG. 1 is a side cross-sectional view of a holding furnace for a die-casting alloy according to one embodiment of the present invention, FIG. 2 is a plan cross-sectional view of a holding furnace for a die-casting alloy according to one embodiment of the present invention, and FIG. 3 schematically shows the structure of an electric heater provided in a holding furnace for a die-casting alloy according to one embodiment of the present invention.

[0049] Referring to FIGS. 1 to 3, a heat retention furnace (100) for die-casting alloy according to the present invention comprises a first heat retention section (110), a second heat retention section (120) formed in communication with one side of the first heat retention section (110), and a molten metal discharge port (130) formed on the other side of the first heat retention section.

[0050] As shown in FIGS. 1 and 2, the first insulation section (110) is formed by stacking refractory bricks in a roughly rectangular shape, and on one side thereis a protrusion formed that protrudes in a shape narrower than the rectangle, and the upper part is covered with a ceiling (111) in the shape of an arch, so that the first space (112) in which the die-casting alloy molten metal is contained forms a sealed structure that is isolated from the outside. This sealed structure is effective in reducing energy loss due to the exposure of the die-casting alloy molten metal to the outside, and at the same time, reducing the generation of impurities such as oxides. On the outer side of the refractory bricks, a housing (113) covering the refractory bricks may be formed of a material such as metal or ceramic.

[0051] In the arch-shaped ceiling (111) covering the upper part of the first insulation section (110), a plurality of burners (114) using gas or diesel fuel are arranged at predetermined intervals.

[0052] As shown in FIGS. 1 and 2, the second insulation section (120) is formed by stacking refractory bricks on one side of the first insulation section (110) in a roughly square shape and the upper part is covered by an electric heating device (121) to form a sealed structure in which the second space (122) in which the die-casting alloy molten metal is contained is isolated from the outside.

[0053] The above electric heating device (121) includes a plurality of electric heaters (122) arranged in a row at predetermined intervals, and the plurality of electric heaters (122) are immersed in molten metal flowing in a second space (121) that is in communication with a first space (112) to heat the molten metal.

[0054] The above electric heater (122) has a structure comprising, as shown in FIG. 3, a high-temperature metal heating element (122a) formed in a U-shape, a heat conductor (122b) arranged in a manner that embeds the high-temperature metal heating element (122a), and a ceramic covering (122c) covering the heat conductor (122b).

[0055] The above high-temperature metal heating element (122a) is made of a metal that has stability even at high temperatures and converts electrical energy into thermal energy. It is desirable that it has a high melting point, operates stably in a high-temperature environment, and has high electrical resistance. For example, it may be made of tungsten or a tungsten alloy, but high-temperature metal heating elements such as molybdenum, tantalum, and nichrome may also be used, and it is not necessarily limited to tungsten.

[0056] The above-mentioned heat conductor (122b) is intended to stably support the high-temperature metal heating element (122a), which is formed in the shape of a U-shaped filament, and to provide electrical insulation, while efficiently transferring heat from the high-temperature metal heating element (122a) to the ceramic coating (122c). For example, magnesium oxide (MgO), alumina (Al2O3), boron nitride (BN), aluminum nitride (AlN), etc., may be used.

[0057] The ceramic coating (122c) prevents the high-temperature metal heating element (122a) from oxidizing at high temperatures and provides electrical stability by imparting electrical insulation. A material that maintains casting stability in a high-temperature environment and has low chemical reactivity with the die-casting molten metal may be used. For example, silicon nitride (Si3N4), which possesses excellent thermal shock resistance and mechanical strength in addition to the above characteristics, may be preferably used. Other materials such as alumina, zirconia, and silicon carbide may also be used. Various methods such as plasma spraying, chemical vapor deposition (CVD), and dip coating may be used as coating methods for the ceramic coating (122c).

[0058] An electric heater (122) having such a structure can provide improved energy efficiency compared to conventional heaters.

[0059] As shown in FIGS. 1 and 2, the molten metal discharge port (130) is formed on one side of the first insulation part (110), and a ladle (200) for receiving a predetermined amount of molten metal is arranged on the outside of the molten metal discharge port (130). In order to prevent the molten metal from overflowing from the ladle when discharging the molten metal, the ladle (200) may be equipped with a means (not shown) for measuring weight.

[0060] A holding furnace (100) for die-casting alloys having the above structure can be used for holding the temperature of already melted molten metal, and can also be used for melting and holding the temperature of die-casting alloys.

[0061] The operation of the holding furnace (100) for die-casting alloy according to the present invention is such that, while the molten metal of the die-casting alloy is contained within the holding furnace (100), the burner (114) and / or electric heater (122) are controlled according to a predetermined set value by a system that monitors the temperature of the molten metal. At this time, since the set value is set considering carbon emissions and energy efficiency, the carbon emissions may be lower or energy efficiency may be increased compared to conventional holding furnaces.

Claims

1. A first thermal insulation part formed with a first space that is sealed off from the outside and is made of a material including a refractory material and accommodates the molten alloy to be die-cast, and It includes a second thermal insulation member formed on one side of the first thermal insulation member, made of a material including a refractory material, communicating with the first space, and having a second space formed therein that is isolated from the outside. In the first insulation section above, a first heating means is provided to heat the molten metal using fossil fuel, and A second heating means for heating the molten metal using electric resistance heat is disposed in the second insulation section above, and A holding furnace for die-casting alloys, wherein a discharge port for discharging the molten metal to the outside is formed on the other side of the first holding portion.

2. In Paragraph 1, The first heating means is a plurality of burners arranged at a predetermined interval on the upper part of the first heat retention section, for a die-casting alloy holding furnace.

3. In Paragraph 1, The above second heating means is used by being immersed in the molten metal, A holding furnace for die-casting alloys, comprising a structure including a high-temperature metal heating element that is linear and generates resistance heat by the application of current, a heat conductor arranged in a manner that embeds the high-temperature metal heating element, and a ceramic coating covering the outer side of the heat conductor.

4. In Paragraph 3, A holding furnace for die-casting alloys, wherein the high-temperature metal heating element comprises tungsten, the heat conductor comprises one or more selected from magnesium oxide (MgO), alumina (Al2O3), boron nitride (BN), and aluminum nitride (AlN), and the ceramic coating comprises Si3N4.

5. In Paragraph 3, The above electric heater is arranged in two or more places in a holding furnace for die-casting alloys.

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