MELTING FURNACE is a device designed for melting a charge of ferrous or non-ferrous metal. The advantages are that the melting mass is perfectly mixed if an induction melting furnace is used for melting metal, due to the action of eddy electric currents. You need a melting furnace with good characteristics? ZAVODRR- transistor, thyristor furnaces for copper, cast iron, aluminum, steel for 5 - 5000 kg.
How are melting furnaces constructed?
How do smelting furnaces work? MELTING FURNACES are good way melt both ferrous and non-ferrous metals, such as aluminum, steel, cast iron, stainless steel, copper. Induction melting furnaces have a simple design and operate under electrical power. magnetic field, are able to evenly mix the metal during melting. Induction furnaces have a lid and a device for draining metal into a casting ladle. The ROSINDUKTOR company offers melting furnaces of transistor or thyristor design with gearboxes and hydraulics.
The advantage of gearbox furnaces is the possibility of manual (emergency) draining of metal; hydraulics is the smooth tilt of the melting unit. Melting furnaces are supplied with one or two melting units, and an inductor is located inside each melting unit. The inductor is made in the form of a copper coil consisting of many turns; the tube can be either round or rectangular in cross-section.
The melting unit is cooled using a chiller or cooling tower. During metal melting, it is necessary to cool two circuits: the reactor (located inside the thyristor converter) and the inductor of the melting unit itself. The melting unit has two versions of the crucible: graphite and lined (made manually from a lined mixture). Graphite crucibles are used for melting non-ferrous metals; for ferrous metals, a lining is used.
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Melting furnaces - transistorized
The transistor induction melting furnace is designed for the charge of ferrous and non-ferrous metals. It is produced on the basis of a mid-frequency induction heater, which is assembled using MOSFET transistors and IGBT modules, which allows saving on electricity up to 35%, having a high efficiency of 95%.
Transistor-based induction melting furnaces are suitable for small industrial foundries that need to melt large number metal The advantages of melting furnaces include their mobility and ease of maintenance, since they use a graphite crucible, which saves time on making the lining and drying it.
The Rosinductor company offers to buy LEGNUM induction melting furnaces (Taiwan); these furnaces are the most popular among Russian buyers. Thyristor induction melting furnaces Legnum are supplied in two modifications: hydraulics and gearboxes, the main buyers are medium and large smelting plants with a capacity of 2000 tons/year.
The induction melting furnace is supplied with two melting units; they are installed on a pre-prepared foundation. The main advantages are efficiency, on average 20-30% more economical than any other analogues presented at Russian market, reliability, modern design And affordable price. Rosinductor supplies induction melting furnaces not only to all regions of RUSSIA, but also to the countries of the former CIS. By contacting our company, rest assured that the induction melting furnace you buy is guaranteed best price, quality, reliability and delivery conditions.
The advantage of melting metal in melting furnaces is cost-effectiveness. This is due to the release of a large amount of heat when heating the metal, so the furnaces consume relatively little power. If we make a comparison between transistor and thyristor furnaces, then the former are 25% more economical, but their cost for the same power is noticeably higher. The most common furnaces have a melting temperature of 1650 °C; at this temperature any non-refractory charge can be melted.
During metal melting, the furnace is controlled mechanically or remotely. In both cases, the process must be managed by trained personnel with appropriate permits and approvals. The Rosinductor company performs work on setting up converters, troubleshooting and maintaining smelting equipment in working order.
When choosing a melting furnace, you need to think about the choice of crucible. This determines what metal will melt and how many melts it can withstand. On average, the crucible can withstand from 20 to 60 heats. For long service crucible, you must use high-quality and reliable materials. The melting time of metal takes no more than 50 minutes in a heated melting furnace, so a furnace of small volume and power can have high performance.
The delivery set of melting furnaces includes the main elements: a thyristor or transistor frequency converter, melting units, capacitor banks, templates, water-cooled cables, control panels, cooling systems.
Induction melting furnace 5 - 5000 kg
Induction melting crucible furnace on 5 - 5000 kg swimming trunks, in a lightweight aluminum alloy body, with TFC and tilt gearbox. An induction crucible furnace with a thyristor converter is designed for melting ferrous and non-ferrous metals in foundries. The furnace is used to heat molten copper, steel and cast iron. Round-the-clock operation of the furnace is possible if necessary.
Melting furnaces for aluminum
Melting furnaces for aluminum have their own characteristics, because the melting point of aluminum is 660 °C (390 kJ/kg). When choosing a furnace for aluminum, you should know that the thyristor converter should not be powerful, and the melting unit itself differs in size from the unit for steel or copper by 2-3 times. Accordingly, it is not recommended to melt other metals in it.
Aluminum alloys can be melted in furnaces with oil, gas and electric heating, in flame reverberatory furnaces, but the highest quality metal and high speed are obtained when melting in induction melting furnaces, due to the homogeneous composition of the charge, which is perfectly mixed in the induction field.
Melting furnaces for steel
Melting furnaces are heated to their maximum temperature when melting steel, 1500 - 1600 ° C and are accompanied by complex physical and chemical processes. When remelting steel, it is necessary to reduce the content of oxygen, sulfur and phosphorus, which form oxide and sulfide elements, which reduce the quality of steel.
A feature of steel melting in melting furnaces is the use of lining mixtures, in contrast to copper melting, where a graphite crucible is used. Melting furnaces mix the metal well due to the induction field, which evens out the chemical composition of the steel.
The above advantages are excellent for smelting alloy steels, with minimal losses of alloying elements: tungsten - about 2%, manganese, chromium and vanadium - 5 - 10%, silicon - 10 - 15%, taking into account the scarcity and high cost of alloying elements.
Steel melting has the following features and advantages:
- The most important castings are melted using the oxidation method, because during the boiling of the metal, all non-metallic inclusions are removed and the phosphorus content is reduced. The composition of the charge is taken from scrap carbon steel or cast iron to obtain an average carbon content of 0.5%;
- If you are going to melt steel with a high content of manganese, aluminum, chromium, you need to choose an acid lining, because the durability of the crucible will be twice as high;
- Before starting melting, the crucible is filled with metal, but the top should not be filled tightly, this can lead to the formation of arches and, accordingly, waste of metal, since the charge will settle during melting of the lower pieces;
- The steel melting time ranges from 50-70 minutes, depending on the heating of the melting unit;
- Melting furnaces for steel have high productivity in the production of castings of small mass and size.
Copper, copper alloys, bronze, brass can be melted in all melting furnaces where the temperature is maintained at 1000 - 1300 °C. However, it is preferable to use induction melting furnaces, since one melt in them will not exceed 40 minutes. The copper used in Russia today is not particularly pure. Typically it contains the following impurities: iron, nickel, antimony, arsenic. Copper with an impurity content of 1% is considered pure metal.
Basics important quality metal has high electrical and thermal conductivity. This determines the low temperature for melting. Copper smelting temperature is 1084°C. Copper is a fairly flexible metal that is widely used in various technical industries, here are some of its features:
- Copper can be melted in an open environment, in a vacuum and in a protective gas environment;
- Copper is melted in a vacuum to obtain oxygen-free copper, with the ability to reduce O (Oxygenium) oxygen to almost zero 0.001%;
- The main charge when producing oxygen-free copper is 99.95% cathode sheets; before loading the sheets into the furnace, they must be cut, washed and dried from the electrolyte;
- The lining of the melting furnace above the metal level is made of magnesite;
- To avoid oxidation, smelting is carried out using charcoal, fluxes, glass and other components.
Induction furnace for metal melting
An induction furnace for melting metal heats the metal mixture with currents high frequency(High Frequency) in an induced electromagnetic field under the influence of eddy electric currents. Melting furnaces consume a large amount of electricity, so we offer furnaces not only with a thyristor converter, but also with an economical transistor converter. The furnace uses a lining or a graphite crucible, in both cases they are only enough for 20-40 melts. High melting point allows one metal melt to be performed in 50 minutes.
ZAVODRR- furnaces for melting metals from Russian, Asian and European manufacturers with a crucible capacity from 1 to 10,000 kg. Supply, installation, commissioning and inexpensive maintenance of furnaces.
Let's look at the features of furnaces for melting ferrous, non-ferrous and precious metals:
- Aluminum smelting furnace (aluminum smelting in furnaces is carried out at a temperature of 660 °C, boiling point 2400 °C, density 2698 kg/cm³);
- Furnace for smelting cast iron (cast iron smelting 1450 - 1520 °C, density 7900 kg/m³);
- Copper smelting furnace (copper smelting 1083°C, boiling point 2580°C, density 8920 kg/cm³);
- Furnace for gold smelting (gold smelting 1063°C, boiling point 2660°C, density 19320 kg/cm³);
- Silver smelting furnaces (silver smelting 960°C, boiling point 2180°C, density 10500 kg/cm³);
- Furnace for steel melting (steel melting in furnaces 1450 - 1520 °C, density 7900 kg/m³);
- Iron smelting furnace (iron smelting 1539°C, boiling point 2900°C, density 7850 kg/m3);
- Furnaces for melting titanium alloys (titanium melting 1680°C, boiling point 3300°C, density 4505 kg/m³);
- Furnace for lead smelting (lead smelting in furnaces 327°C, boiling point 1750°C, density 1134 kg/cm³);
- Brass smelting furnace (brass smelting in furnaces 880–950 °C. density 8500 kg/m³);
- Bronze smelting furnaces (bronze smelting in furnaces, 930–1140 °C 8700 kg/m³).
An induction furnace is used for melting non-ferrous and ferrous metals. Units of this operating principle are used in the following areas: from the finest jewelry making to large-scale industrial smelting of metals. This article will discuss the features of various induction furnaces.
Induction furnaces for metal melting
Operating principle
Induction heating is the basis for the operation of the furnace. In other words, electric current creates an electromagnetic field and heat is obtained, which is used on an industrial scale. This law of physics is studied in the last grades secondary school. But the concept of an electric unit and electromagnetic induction boilers should not be confused. Although the basis of work here and there is electricity.
How it happens
The generator is connected to the source AC, which enters it through an inductor located inside. The capacitor is used to create an oscillation circuit, which is based on a constant operating frequency to which the system is tuned. When the voltage in the generator increases to a limit of 200 V, the inductor creates an alternating magnetic field.
The circuit is closed most often through a ferromagnetic alloy core. The alternating magnetic field begins to interact with the workpiece material and creates a powerful flow of electrons. After the electrically conductive element enters into inductive action, occurrence of residual stress, which in the capacitor contributes to the occurrence of eddy current. Eddy current energy is converted into thermal energy inductor and the desired metal is heated to high melting temperatures.
The heat produced by the inductor is used:
- for melting soft and hard metals;
- for hardening the surface of metal parts (for example, tools);
- for thermal treatment of already produced parts;
- household needs (heating and cooking).
Brief characteristics of various furnaces
Types of devices
Induction crucible furnaces
It is the most common type of induction heating furnace. Distinctive feature, different from other types is that in it an alternating magnetic field appears in the absence of a standard core. Cylinder shaped crucible placed inside the inductor cavity. The furnace, or crucible, is made of a material that perfectly resists fire and is connected to alternating electric current.
Positive aspects
Crucible units include to environmentally friendly heat sources, environment not polluted by metal melting.
There are disadvantages in the operation of crucible furnaces:
- during technological processing, slags at low temperatures are used;
- The produced lining of crucible furnaces has low resistance to destruction, this is most noticeable during sudden temperature changes.
The existing disadvantages do not pose any particular difficulties; the advantages of a crucible induction unit for melting metal are obvious and have made this type of device popular and in demand among a wide range of consumers.
Channel induction melting furnaces
This type is widely used in the smelting of non-ferrous metals. Effectively used for copper and copper alloys based on brass, cupronickel, bronze. Aluminum, zinc and alloys containing these metals are actively melted in channel units. The widespread use of furnaces of this type is limited due to the inability to provide a fracture-resistant lining on the inner walls of the chamber.
Molten metal in channel induction furnaces undergoes thermal and electrodynamic movement, which ensures constant homogeneity of mixing of alloy components in the furnace bath. The use of channel furnaces of the induction principle is justified in cases where special requirements are imposed on the molten metal and manufactured ingots. The alloys are of high quality in terms of gas saturation coefficient and the presence of organic and synthetic impurities in the metal.
Channel induction furnaces operate like a mixer and are designed to level the composition, maintain a constant process temperature, and select the pouring speed into crystallizers or molds. For each alloy and casting composition, there are parameters for a special charge.
Advantages
- the alloy is heated in the lower part, to which there is no air access, which reduces evaporation from the upper surface, heated to a minimum temperature;
- channel furnaces are classified as economical induction furnaces, since the melting that occurs is ensured by a low consumption of electrical energy;
- the furnace has a high efficiency due to the use of a closed loop magnetic wire;
- Constant circulation of molten metal in the furnace accelerates the melting process and promotes uniform mixing of alloy components.
Flaws
- the durability of the stone internal lining decreases when high temperatures are used;
- the lining is destroyed when melting chemically aggressive alloys of bronze, tin and lead.
- when melting contaminated low-grade charge, the channels become clogged;
- the surface slag in the bath does not heat up to a high temperature, which does not allow operations to be carried out in the gap between the metal and the shelter and to melt chips and scrap;
- channel units do not tolerate interruptions in operation, which forces them to constantly store a significant amount of liquid alloy in the furnace mouth.
Complete removal of molten metal from the furnace leads to its rapid cracking. For the same reason, it is impossible to perform a quick conversion from one alloy to another, you have to make several intermediate melts, called ballast.
Vacuum induction furnaces
This type is widely used for melting high quality steels and heat-resistant nickel, cobalt and iron alloys. The unit successfully copes with the melting of non-ferrous metals. Glass is boiled in vacuum units, parts are treated with high temperature, produce single crystals.
The furnace is classified as a high-frequency generator located in an isolated external environment an inductor that passes high frequency current. To create a vacuum, air masses are pumped out of it. All operations for introducing additives, loading the charge, and dispensing metal are carried out automatic mechanisms with electric or hydraulic control. Alloys with small admixtures of oxygen, hydrogen, nitrogen, and organics are obtained from vacuum furnaces. The result is far superior to open induction ovens.
Heat-resistant steel from vacuum furnaces used in tool and weapons production. Some nickel alloys containing nickel and titanium are chemically active, and it is problematic to obtain them in other types of furnaces. Vacuum furnaces perform metal pouring by rotating the crucible in the internal space of the casing or by rotating the chamber with a fixed furnace. Some models have an opening hole in the bottom to drain metal into an installed container.
Crucible furnaces with transistor converter
Used for limited weight non-ferrous metals. They are mobile, light in weight and can be easily moved from place to place. The furnace package includes a high-voltage transistor universal converter. Allows you to select the power recommended for connecting to the network, and, accordingly, the type of converter that is needed in this case with changing the weight parameters of the alloy.
Transistor Induction Furnace Widely used for metallurgical processing. With its help, parts are heated in blacksmithing and metal objects are hardened. Crucibles in transistor furnaces are made of ceramics or graphite; the former are designed to melt ferromagnetic metals such as cast iron or steel. Graphite is installed to melt brass, copper, silver, bronze and gold. They melt glass and silicon. Aluminum melts well using cast iron or steel crucibles.
What is the lining of induction furnaces
Its purpose is to protect the furnace casing from the destructive effects of high temperatures. Side effects is heat conservation, therefore process efficiency increases.
The crucible in the design of an induction furnace is made in one of the following ways:
- by the method of excavation in small-volume ovens;
- by the printed method from refractory material in the form of masonry;
- combined, combining ceramics and a buffer layer between the masonry and the indicator.
The lining is made of quartzite, corundum, graphite, fireclay graphite, magnesite. Additives are added to all these materials to improve the characteristics of the lining, reduce volume changes, improve sintering, and increase the resistance of the layer to aggressive materials.
To select a particular material for lining take into account a number of accompanying conditions, namely, the type of metal, the price and refractory properties of the crucible, the service life of the composition. A properly selected lining composition should provide technical requirements to carry out the process:
- obtaining high quality ingots;
- the largest amount of full melting without repair work;
- safe work of specialists;
- stability and continuity of the smelting process;
- obtaining high-quality material using an economical amount of resources;
- use of common materials for lining at a low price;
- minimal impact on the surrounding space.
The use of induction furnaces allows you to obtain alloys and metals of excellent quality with a minimum content of various impurities and oxygen, which increases their use in complex areas of production.
Induction melting furnace has been used for melting metals and alloys for the past few decades. The device has become widespread in the metallurgical and mechanical engineering fields, as well as in jewelry. If you wish, you can make a simple version of this equipment yourself. Let's take a closer look at the operating principle and features of using an induction furnace.
Induction heating principle
In order for metal to move from one state of aggregation others require heating it to a fairly high temperature. Moreover, each metal and alloy has its own melting point, which depends on chemical composition and other points. An induction melting furnace heats the material from the inside by creating eddy currents that pass through the crystal lattice. The process under consideration is associated with the phenomenon of resonance, which causes an increase in the strength of eddy currents.
The operating principle of the device has the following features:
- The space that is formed inside the coil serves to accommodate the workpiece. Use this heating method in industrial conditions This is possible only if a large device is created into which batches of various sizes can be placed.
- The installed coil can have different shapes, for example, a figure of eight, but the most common is the spiral. It is worth considering that the shape of the coil is selected depending on the characteristics of the workpiece subjected to heating.
In order to create an alternating magnetic field, the device is connected to a household power supply network. To improve the quality of the resulting alloy with high fluidity, high-frequency generators are used.
Design and use of an induction furnace
If desired, you can create an induction furnace for melting metal from scrap materials. The classic design has three blocks:
- A generator that creates high frequency alternating current. It is this that creates an electric current, which is converted into a magnetic field passing through the material and accelerating the movement of particles. Due to this, the transition of metal or alloys from solid to liquid occurs.
- The inductor is responsible for creating a magnetic field, which heats the metal.
- The crucible is designed for melting material. It is placed in an inductor, and the winding is connected to current sources.
Conversion process electric current in a magnetic field is used today in a wide variety of industries.
The main advantages of the inductor include the following points:
- A modern device is capable of directing a magnetic field, thereby increasing efficiency. In other words, the charge is heated, not the device.
- Due to the uniform distribution of the magnetic field, the workpiece is heated evenly. In this case, from the moment the device is turned on until the charge is melted, a small amount of time takes place.
- The homogeneity of the resulting alloy, as well as its high quality.
- When the metal is heated and melted, no evaporation is formed.
- The installation itself is safe to use and does not cause the formation of toxic substances.
There is just a huge amount various options designs of homemade induction furnaces, each with its own specific features.
Types of induction furnaces
Considering the classification of devices, we note that the workpieces can be heated both inside and outside the coil. That is why there are two types of induction furnaces:
- Channel. This kind of device has small channels that are located around the inductor. To generate an alternating magnetic field, a core is located inside.
- Crucible. This design is characterized by the presence of a special container called a crucible. It is made of refractory metal with a high melting point.
It is important that channel induction furnaces have large overall dimensions and are intended for industrial metal melting. Due to the continuous melting process, a large volume of molten metal can be obtained. Channel induction furnaces are used for melting aluminum and cast iron, as well as other non-ferrous alloys.
Crucible induction furnaces are characterized by relatively small sizes. In most cases, this kind of device is used in jewelry, as well as when melting metal at home.
When creating a furnace with your own hands, you can adjust the power by changing the number of turns. It is worth considering that as the power of the device increases, a larger battery is required, as the energy consumption increases. In order to reduce the temperature of the main structural elements, a fan is installed. During long-term operation of the stove, its main elements can heat up significantly, which is worth taking into account.
Lamp-based induction furnaces have become even more widespread. You can make a similar design yourself. The assembly process has the following features:
- A copper tube is used to create an inductor, for which it is bent in a spiral. The ends must also be large, which is required to connect the device to a current source.
- The inductor should be placed in the housing. It is made of heat-resistant material that can reflect heat.
- The lamp cascades are connected according to a circuit with capacitors and chokes.
- The neon indicator lamp is connected. It is included in the circuit to indicate that the device is ready for operation.
- A variable capacitor is connected to the system.
An important point is how the system can be cooled. When operating almost all induction furnaces, the main structural elements can heat up to high temperatures. Industrial equipment has a forced cooling system that runs on water or antifreeze. In order to create a water cooling design with your own hands, quite a lot of money is required.
At home, an air cooling system is installed. For this purpose, fans are installed. They should be positioned so as to ensure a continuous flow of cold air to the main structural elements of the furnace.
For melting metal on a small scale, some kind of device is sometimes necessary. This is especially acute in a workshop or in small-scale production. The most efficient furnace at the moment is a metal melting furnace with an electric heater, namely an induction furnace. Due to the peculiarities of its structure, it can be effectively used in blacksmithing and become an indispensable tool in the forge.
Induction furnace structure
The oven consists of 3 elements:
- 1. Electronic and electrical part.
- 2. Inductor and crucible.
- 3. inductor cooling system.
In order to assemble a working furnace for melting metal, it is enough to assemble a working electrical diagram and an inductor cooling system. The simplest version of metal melting is shown in the video below. Melting is carried out in the counter electromagnetic field of the inductor, which interacts with induced electro-eddy currents in the metal, which holds a piece of aluminum in the space of the inductor.
In order to effectively melt metal, large currents and high frequencies of the order of 400-600 Hz are required. The voltage from a regular 220V home socket is sufficient to melt metals. It is only necessary to turn 50 Hz into 400-600 Hz.
Any circuit for creating a Tesla coil is suitable for this. I liked the following 2 circuits on the GU 80, GU 81(M) lamp the most. And the lamp is powered by an MOT transformer from a microwave oven.
These circuits are intended for a Tesla coil, but they make an excellent induction furnace; instead of the secondary coil L2, it is enough to place a piece of iron in the internal space of the primary winding L1.
The primary coil L1 or inductor consists of a copper tube rolled into 5-6 turns, the ends of which are threaded to connect the cooling system. For levitation melting, the last turn should be done in the opposite direction.
Capacitor C2 in the first circuit and an identical one in the second sets the frequency of the generator. At a value of 1000 picoFarads, the frequency is about 400 kHz. This capacitor must be high-frequency ceramic and designed for high voltage about 10 kV (KVI-2, KVI-3, K15U-1), other types are not suitable! It's better to use K15U. Capacitors can be connected in parallel. It is also worth taking into account the power for which the capacitors are designed (this is written on their case), take it with a reserve. the other two capacitors KVI-3 and KVI-2 heat up during prolonged operation. All other capacitors are also taken from the KVI-2, KVI-3, K15U-1 series; only the capacitance changes in the characteristics of the capacitors.
Here is a schematic diagram of what should happen. I circled 3 blocks in frames. 
The cooling system is made of a pump with a flow of 60 l/min, a radiator from any VAZ car, and I placed a regular home cooling fan opposite the radiator.
Aluminum alloys have low melting point and good workability details. And there is always a lot of aluminum scrap on the farm.
That's why aluminum is often melted at home to replace non-standard or small parts of mechanisms: a blank is cast, and then processed lathe. Sometimes souvenirs and small interior items are made from aluminum with their own hands.
Melting furnace structure
Homemade furnaces for melting aluminum consist of a body - metal cylinder (2), lined with refractory (clamotte with sand or concrete). Inside the mine is charcoal (8), serving as fuel. It is installed crucible (3)- a container in which the metal will melt. The crucible can be a thick tin can, a teapot or any stainless steel container.
At the bottom of the shaft (6) made air injection hole (7) through lattice base (4), which allows you to maintain combustion and regulate the temperature in the furnace.
A hair dryer or a vacuum cleaner pipe is used as a blower. Damper (5) necessary to remove excess air.
For ovens with a capacity of several tens of kilograms, you need cover (1) for quick and uniform heating of the metal. In small ovens you can do without it.
Furnace elements should not deform or melt when heated. Therefore, the use of aluminum bodies, tubes and crucibles is unacceptable. It is best to take steel or cast iron details.
Reference. It is also used as fuel for smelting aluminum. natural gas or electricity.
How to make a furnace for melting metal?
Creating a small unit that can melt several kilograms of scrap aluminum is not a difficult task. To lay out the oven on garden plot will be required following materials:
- red bricks - 20-25 pcs.;
- high tin can - 1 pc.;
- grill grate - 1 pc.;
- drying hair dryer - 1 pc.;
- piece of pipe, with a diameter suitable for the outlet of the hair dryer - 1 piece;
- roll of electrical tape;
- segment steel wire length 30-50 cm;
- coal for ignition (the quantity depends on how much aluminum needs to be melted).
The bricks will appear simultaneously and body and fireproof coating oven, a tin can will act as a crucible. At the top of the can are being done two holes opposite each other, and through them the wire is threaded. It will be possible to lift and remove the crucible with the melt from the furnace. The air will be supplied from the hairdryer turned on in cold air mode. Tape or tape to the outlet of the hair dryer attach a piece of pipe- this will be the air duct.
Such simple circuit The furnace is convenient because no tools are actually required to create it; everything is done by hand.
Important! Do not use oven elements with zinc coating, because when aluminum is melted, toxic zinc fumes will be released.
Brick well installation plan
- Gives his all one row bricks in the form of a rectangular well. The internal dimensions of the hole should be approximately length and width of one brick. On one side two bricks laid out so as to form a corridor for the air duct. The width of the corridor is tube diameter for air supply.
- On the laid out row grating is installed. Instead of a grill grate, you can use any metal cover or a plate with holes for air supply.
- Placed on the grill second row bricks, without any gap for the air duct.
Photo 1. Finished brick well for the melting furnace. The edges are reinforced with metal strips, the air duct opening is visible.
- Created air duct. Tape or tape to the hairdryer a piece of pipe is wound. To ensure structural strength, the connection point turns around thick paper , and then connects duct tape. Electrical tape is a more elastic material compared to adhesive tape, so it is more convenient to work with. The cold air supply button is also secured with tape on the hairdryer. Ready the mechanism is brought to the bottom row bricks.
- In the stove well on the grate coal is poured and melted for ignition. The hair dryer turns on, which activates the combustion process.
Advice. The air supply intensity can be adjusted by changing hair dryer operating mode, and also distance between pipe and window for the air duct.
- Tin is installed to the top row bricks for the wire threaded into it. Like a pot over a fire, it hangs over the grate.
- After lighting the furnace and installing the crucible third row are placed two more bricks so that from a rectangular hole you get a square one. This will fix the can inside the housing and heat up the oven space faster.
After heating the jar into it scrap can be loaded for remelting. A sign that the jar is warming up is its redness.
The principle of the design and operation of such a furnace is very simple and does not cause difficulties. However, it is always worth remembering safety precautions:
- work in fire-resistant gloves;
- avoid water getting into the melt;
- do not use materials containing toxic substances.
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Two-can design
Another variety homemade stove for melting aluminum is a design made of two large cans. One of them serves body, in which a hole is cut for air supply, and bottom of the second jars with holes serves as a divider.
A crucible is installed inside the jars.
Such a device very compact, and small volumes of metal can be melted even in a ventilated garage. However, the design is not resistant or fire resistant, and will only last a few cycles.
Possible problems and their solutions
Carelessly assembled device causes the oven to operate inefficiently and makes it dangerous to use. Here are a few points to pay attention to:
- Slots and gaps in a brick building. They can be caused by chips on bricks or loose fit of refractories to each other. Gaps reduce fuel efficiency and reduce combustion intensity and temperature. Aluminum in a crucible may simply not melt.
Therefore, after laying out each row, a visual check is carried out for the presence of holes. Holes covered with a sand-clay mixture or covered with fire-resistant material.
It is recommended to use concrete mortar only in the case of a stationary unit that is not planned to be disassembled. But Asbestos sheets and chips should not be used in places where the stove is heated, because this material is a carcinogen.
- Violation of the horizontal level buildings. Misalignment reduces the stability of the structure and creates conditions for uneven distribution of coal. The result is uneven heating of the crucible and the metal in it.
Laying out each, especially the bottom row of bricks controlled by level. You can also check horizontality placing a jar of water on the grill. On a flat surface, the top edge of the water will be parallel to the edge of the can.