Aluminum melting furnace. How to assemble an induction furnace for melting metal at home with your own hands Melting furnace

The author who made this stove went one of the easiest ways. He made a prototype of a simple furnace for melting aluminum with his own hands from materials that are lying around in the yard of any rural house or in the country.

Working without protection is dangerous!

But look how many hot material rules he breaks. There is no longer any question that he does not have goggles and special outerwear. He simply belongs to the risk group, because he did not wear the most necessary things in the smelting business - well-protected shoes with thick leather and a high top! Do not forget about the dangers of aluminum fumes. Finished melting furnaces in this shop.

Important advantages of the smelter

But let's give credit to his ingenuity. After all, obviously not having the necessary amount of knowledge, he managed to create a working melting furnace for aluminum, which is heated to the desired temperature and produces molten aluminum at the exit. It can be obtained from beer cans. The design includes a hair dryer for blowing air and providing an increase in temperature due to the supply of air, an impromptu stove made of a tin can, a melting cup, or rather a mug, a protective barrier made of bricks. there is material about other options for furnaces and technologies for working with aluminum.

INDUCTION OVEN OWN HANDS: CHAIN, INSTALLATION

At present, induction furnaces are widely used for melting metals. The current generated in the region of the inductor contributes to the heating of the substance, and this characteristic of such devices is not only basic, but also the most important. Processing causes the substance to undergo several transformations. The first stage of transformation is the electromagnetic phase, then the electrical phase, and then the thermal phase. The temperature that the stove offers is practically unlimited, so this is the best solution for everyone else. Many people may be interested in a DIY induction oven. We will also talk about the possibilities for implementing such a solution.

Types of smelting furnaces

This type of equipment can be roughly divided into main categories. In the first case, the heart channel acts as a base, and the metal is placed in such furnaces in an annular manner around the inductor. The second category has no such element. This type is called a crucible and the metal is placed inside the inductor itself. In this case, it is technically impossible to use a closed kernel.

Basic principles

The melting furnace in this case works on the basis of the phenomenon of magnetic induction. And here are some of the ingredients. The inductor is the most important component of this device. This is a coil, conductors in which there are no ordinary wires, but copper pipes. This requirement is implemented in the design of melting furnaces. The current passing through the inductor generates a magnetic field that affects the crucible containing the metal. In this case, the material is assigned the role of the coil of the secondary transformer, i.e. a current flows through it, which has just heated it. And melting occurs even if the induction furnace is made by itself. How to build this type of furnace and improve its efficiency? This is an important question. The use of high-frequency currents can significantly increase the efficiency of the equipment.

Characteristics of induction furnaces

This type of equipment has some features that are advantages and disadvantages.

Since the distribution of the metal must be formed, the resulting material is characterized by a good homogeneous mass. This type of furnace works by transporting energy through the zones and introduces the function of energy focusing. Parameters such as power, operating frequency and cladding method, as well as temperature control in which the metal is melted, are available for use, which greatly facilitates the workflow. The existing technological potential of the furnace creates a high degree of melting, the devices are environmentally friendly, completely safe for people and ready to work at any time.

The most noticeable disadvantage of such equipment is the difficulty of cleaning. Since the heating of the slag is only due to the heat generated by the metal, this temperature is not enough to ensure full utilization. The high temperature difference between the metal and the slag does not make the waste disposal process as easy as possible. As another disadvantage, the distribution of the gap is common, so it is always necessary to reduce the thickness of the lining. Due to such actions, after a while it may not be correct.

The use of induction furnaces on an industrial scale

In industry - induction furnaces. At the first melting of metals in random quantities. Metal tanks in such variants can hold up to several tons of metal. Of course, do-it-yourself induction melting furnaces cannot be made in this case. Kitchen furnaces are designed for melting non-ferrous metals of various types, as well as cast iron.

This topic is often interested in ham radio design and radio engineering. It is now clear that DIY induction furnaces are quite realistic and a lot can be done. However, to create such equipment, it is necessary to perform the action of an electrical circuit that will contain the prescribed actions of the furnace itself. Such solutions require the inclusion of high-frequency generators capable of generating signals. A simple do-it-yourself induction furnace can be built using a four-pipe tube combined with a neon signal that the system is ready to work.

In this case, the variable capacitor is not inside the device. Therefore, an induction furnace can be created by hand. The device diagram describes the location of each individual element. Make sure the device is powerful enough, you can use a screwdriver which should get hot in just a few seconds.

services

If you create an induction furnace with your own sieve, the principle of operation and assembly of which is studied and produced in accordance with the appropriate scheme, you should be aware that in this case one or more of the following factors can influence the melting rate:

is the pulse frequency;

– loss of hysteresis;

– generator power;

– period of external heating;

– losses associated with the appearance of eddy currents.

If you are going to bake an induction cooker, then when using lamps, you must remember that their power must be distributed so that four are enough. Using a rectifier will result in a network of approximately 220V.

Home use of stoves

Household appliances are used, although such technologies can be found in heating systems. They can be seen in the form of microwave ovens, electric ovens, and induction hobs. In the midst of new technologies, this development has become a widespread application. For example, the use of eddy currents in induction heaters allows you to cook a huge variety of dishes. Since they take very little time to heat up, the stove cannot be turned on if there is nothing. However, special utensils must use such special and useful marks.

Create a process

The crucible induction furnace consists of an inductor which is formed by a coil of water-cooled copper from the crucible and can be made of ceramic materials and sometimes steel, graphite, etc. With such a device, you can melt cast iron, steel, precious metals, aluminum, copper, magnesium. Do-it-yourself induction furnaces are made with a crucible from several kilograms to several tons. They can be evacuated, gas filled, open and compressed. Furnaces are powered by high, medium and low frequencies.

So, if you are interested in an induction furnace, the scheme involves the use of such basic installations: a melting bath and an induction installation, which includes a stone, an inductor and a magnetic core. A channel other than a crucible furnace, so that electromagnetic energy is converted into heat in a thermal channel, which must be a continuously electrically conductive body. To obtain the beginning of the primary channel of the furnace, liquid molten metal or a model of material capable of cracking in the furnace is added. When the melting is completed, the metal is not completely drained, but in the future it remains a "swamp" to fill the heat channel for starting. If the induction furnace is assembled by hand, it is removed to facilitate the replacement of the hardware stone.

Furnace components

Therefore, if you are interested in a mini induction oven, your own hands are important to know that its main element is the heating coil. In self-service mode, it is sufficient to use a bare copper wire inductor with a diameter of 10 mm. For the inductor, the inner diameter is 80-150 mm, and the number of revolutions is 8-10. It is important that the coils do not touch, and the distance between them is 5-7 mm. Parts of the inductor must not touch its screen, the minimum clearance must be 50 mm.

If you are going to bake an induction oven, you should know that industrial scales are cooled with water or antifreeze. In case of low power and short operation of the device, you can do it without cooling. But when you work, the inductor is very hot, and the copper scale can not only drastically reduce the efficiency of the device, but also lead to a complete loss of efficiency. It is impossible to create a self-cooling inductor, so regular replacement is required. Do not use forced air cooling, because in the case of a fan located near the coil, it will "attract" EMF to itself, which will lead to overheating and reduce the efficiency of the furnace.

generator

When an induction furnace is built by hand, the circuit involves the use of such an important element as an alternator. Don't try to make an oven if you don't know the basics of radio electronics, at least to the level of an average radio amateur. The choice of oscillator circuit must be such that it does not give a continuous range of current.

Use of induction furnaces

This type of equipment is common in areas such as the foundry where the metal has already been cleaned and a specific mold needs to be placed. You can also get some alloys. They are also widely used in jewelry. The simple working principle and the ability to collect induction with your hands can improve the cost-effectiveness of its use. For this area, it can be used with crucible devices with a capacity of up to 5 kg. For small productions, this option will be optimal.

MELTING FURNACE is a foundry furnace with an inductor for melting metal. The advantage is that the melting mass is perfectly mixed to a homogeneous composition if an induction melting furnace is used. Induction technology speeds up the process of melting metal (melting time 45 minutes), such furnaces have good performance! ZAVODRR – melting furnaces for steel, aluminum, copper from professionals!

How are melting furnaces arranged?

Melting furnaces are a working chamber into which the feedstock (charge), materials and materials that intensify the formation of the melt are placed. The chamber is separated from the outer casing by means of a refractory lining, as well as a heat-insulating layer. Depending on the type of energy carrier used or the heating method (induction method, graphite electrodes, gas burners), the device of the chamber depends, as well as the time and quality of the output material. Let's look at the device of melting furnaces.

- IN arc melting furnaces a device for draining the melt and separating slag masses is located in the lower part of the furnace. Electrodes are placed on top of their number from 1 to 4 pieces. A transformer acts as a power source. The disadvantage of this method may be the sintering of the metal.

– induction melting furnace consists of an inductor, inside of which there is a crucible with a refractory lining. The equipment is equipped with charge loading mechanisms, systems that provide complete discharge of the finished melt, control and adjustment systems. In induction melting furnaces, the metal is poured from the top. Thyristor or transistor converters act as a power source. The quality of the remelted metal in this way is the best, because the induction method is a constant uniform mixing of the charge during melting; The device of melting furnaces depends on their type.

– Gas Melting Furnaces have the simplest and cheapest design. A gas burner is connected to the melting unit in the lower part, which runs on ordinary main gas (methane). Typically, these furnaces are used to remelt metals with a low specific calorific value, such as aluminum or copper.

Melting Furnaces - Benefits

When choosing a melting furnace, you need to know its disadvantages and advantages. The main advantage of gas melting furnaces is the minimum cost of melting metal, because gas is the cheapest energy carrier. Induction melting furnaces provide excellent melt quality at the outlet. Electric arc - to reach the maximum melting temperature, for refractory materials or alloys. All types of furnaces have good process automation and a small amount of harmful atmospheric emissions.

The advantages of using induction furnaces are obvious:

• production technology makes it possible to obtain high-quality melts with a uniform chemical composition,
• it is possible to introduce additional alloying elements,
• furnaces have a high efficiency of about 95%,
• comparatively small waste,
• production technology that is safe for the health of personnel,
• production efficiency achieved by generating a large amount of heat from the metal, which allows less power to be consumed.

The main characteristics of thermal installations are the capacity of the working chamber, which determines the productivity, the type of material for which it is intended to be smelted, and the rated power of the heating element, which sets the maximum operating temperature, as well as the energy intensity of the process.

Paying attention to the characteristics of the equipment when choosing induction furnaces, it is worth paying special attention to the quality of the crucible. On average, the crucible is designed for the number of heats from 20 to 60. The set of the induction furnace, in addition to the crucible, includes:

• frequency converter (transistor or thyristor),
• capacitor banks,
• melting knots,
• water cooled cables,
• cooling systems and control panels.

Management and control over the melting process must be carried out by specially trained personnel.

The heating element of such installations can operate both in industrial and medium frequencies. The advantages of this solution are complete control over oxidative processes, as well as complete draining of the melt. Both acidic and basic materials can be used as lining materials.

Melting furnaces for melting metal are the most demanded equipment for metallurgical enterprises. Induction melting furnaces make the melting process more economical and of higher quality. Depending on the type of metal and the volume of the charge, the process of melting metal in an induction furnace takes on average from 30 minutes to 1.5 hours. Induction furnaces allow for heat treatment of ferrous, non-ferrous and even precious metals.

Steel melting occurs at a temperature of 1500-1600 degrees Celsius. In the smelting process, it is necessary to reduce the content of substances that degrade the quality of steel, such as sulfur, phosphorus and oxygen. The choice of lining depends on the composition of the desired melt. Induction furnaces are ideal for the production of alloy steels. The melting time of steel takes on average about 1 hour.

These ovens operate mainly at industrial frequencies of 50 Hz and are equipped with high-precision automation that allows you to control both temperature and segregation intensity. The amount of waste in them barely reaches 2%, in addition, they are not demanding on the quality of preparation of charge materials.

The melting point of aluminum is 660 degrees Celsius, so it is important that the thyristor converter is not too powerful. An aluminum melting unit should not be used to melt other metals. The use of an induction furnace for melting aluminum and its alloys will make it possible to obtain a homogeneous melt of high quality.

A distinctive feature of such furnaces is the low heating temperature and. as a result, low power consumption. Graphite is common as the main material for the crucible, in addition, to intensify the process, a metal core can also be used, connected to the medium-frequency network through a step-down transformer. The maximum heating temperature, as a rule, does not exceed 750 ºС.

Melting furnaces for copper

Melting copper in an induction furnace takes no more than 40 minutes. The process of obtaining the melt occurs at a temperature of 1000-1300 degrees Celsius. Melting can be done in a vacuum, in a protective gas environment or in an open environment. Due to its high thermal and electrical conductivity and flexibility, copper is widely used in various industries.

In the production of copper melt, it is very important to ensure chemical purity, therefore, furnaces, in some cases, have a sealed working chamber, and induction heating is carried out in a soft mode. There are no significant structural differences from induction furnaces for non-ferrous metals, but the main requirement is the absence of a direct reaction between the crucible material and the melt.

Melting Furnaces - Transistor

Small foundries use transistorized furnaces to melt charge. These ovens use a medium frequency induction heater. Melting of metals is carried out in a graphite crucible. In transistorized furnaces, there is a dynamic circulation of the metal melt inside the crucible, due to which the temperature is equalized throughout the volume of the crucible, which contributes to obtaining a homogeneous chemical composition of the multicomponent alloy. In such furnaces, a quick transition from an alloy of one grade to another is possible.

Transistor induction furnaces are distinguished by versatility and extremely high efficiency, which can reach 99%, instead of the usual copper winding, they use an induction-type heater assembled on a system of interconnected transistors. An advantage is the electrodynamic circulation, which ensures uniform mixing of the melt.

Another type of induction furnaces are installations. In which, to stabilize the heating process and ensure the possibility of its regulation, thyristor frequency converters of current are used, which ensure the formation of an electromagnetic field.

The induction furnace is used for melting non-ferrous and ferrous metals. Units of this principle of operation are used in the following areas: from the finest jewelry to industrial smelting of metals in large sizes. This article will discuss the features of various induction furnaces.

Induction furnaces for metal melting

Principle of operation

Induction heating is the basis for the operation of the furnace. In other words, electric current generates an electromagnetic field and heat is obtained, which is used on an industrial scale. This law of physics is studied in the last grades of a comprehensive school. But the concept of an electrical unit and electromagnetic induction boilers should not be confused. Although the basis of the work here and there is electricity.

How does this happen

The generator is connected to an alternating current source, 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 rises to a limit of 200 V, the inductor creates an alternating magnetic field.

The closure of the circuit occurs, most often, by means of a core made of a ferromagnetic alloy. An alternating magnetic field begins to interact with the workpiece material and creates a powerful electron flow. After the entry into the inductive action of the electrically conductive element in the system, occurrence of residual stress, which in the capacitor contributes to the occurrence of eddy current. The energy of the eddy current is converted into the thermal energy of the inductor and is heated to high melting temperatures of the desired metal.

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 processing of already produced parts;
• household needs (heating and cooking).

Brief description of various furnaces

Varieties of devices

Induction crucible furnaces

It is the most common type of furnace induction heating. A distinctive feature, different from other types, is that in it an alternating magnetic field appears in the absence of a standard core. Cylindrical crucible placed inside the inductor cavity. The furnace, or crucible, is made of a material that resists fire perfectly and is connected to an alternating electric current.

Positive aspects

Crucible aggregates include to environmentally friendly heat sources, the environment is not polluted by the smelting of metals.

There are disadvantages in the operation of crucible furnaces:

• low-temperature slags are used during technological processing;
• the produced lining of crucible furnaces has a low resistance to destruction, most of all it is noticeable at sharp temperature fluctuations.

The existing disadvantages are not particularly difficult, 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 furnaces for induction melting

This type has found wide application in the smelting of non-ferrous metals. It is effectively used for copper and copper alloys based on brass, cupronickel, bronze. Aluminum, zinc and alloys in the composition of these metals are actively melted in channel units. Widespread use of furnaces of this type is limited due to the impossibility of making a fracture-resistant lining on the inner walls of the chamber.

Molten metal in induction type channel furnaces thermal and electrodynamic motion, which ensures constant uniformity of mixing of the 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, the presence of organic and synthetic impurities in the metal.

Induction channel furnaces work like a mixer and are designed to level the composition, maintain a constant process temperature, and select the pouring speed into molds or molds. For each alloy and casting composition, there are parameters of a special charge.

Advantages

• the heating of the alloy occurs 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 ongoing melting is ensured by a small consumption of electrical energy;
• the furnace has a high efficiency due to the use of a closed circuit of a magnetic wire;
• the constant circulation of molten metal in the furnace accelerates the smelting process and contributes to the homogeneity of the mixing of the alloy components.

Flaws

• the durability of the stone inner lining is reduced when using high temperatures;
• the lining is destroyed during the melting of chemically aggressive alloys of bronze, tin and lead.
• when melting a contaminated low-grade charge, clogging of the channels occurs;
• surface slag in the bath does not heat up to a high temperature, which does not allow operations to be carried out between the metal and the cover and to melt chips and scrap;
• channel units do not tolerate interruptions in operation, which makes it necessary to constantly store a significant amount of liquid alloy in the furnace mouth.

The 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 heats, called ballast.

Vacuum induction furnaces

This type is widely used for melting high quality steels and nickel, cobalt and iron alloys of heat-resistant quality. The unit successfully copes with the melting of non-ferrous metals. Glass is melted in vacuum units, parts are treated with high temperature, produce single crystals.

The furnace is referred to as a high-frequency generator located in an inductor isolated from the external environment, passing a high-frequency current. To create a vacuum, air masses are pumped out of it with pumps. All operations for the introduction of additives, charge loading, metal issuance are carried out by automatic mechanisms with electric or hydraulic control. From vacuum furnaces, alloys are obtained with small impurities of oxygen, hydrogen, nitrogen, and organic matter. 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 reactive and difficult to obtain in other types of furnaces. Vacuum furnaces perform pouring of metal by turning the crucible in the inner space of the casing or by rotating the chamber with a fixed furnace. Some models have an opening in the bottom to drain the metal into the installed container.

Crucible furnaces with transistor converter

Applied to a limited weight of non-ferrous metals. They are mobile, light in weight and easily moved from place to place. The oven is supplied with a high-voltage transistor universal action transducer. Allows you to select the power recommended for connection to the network, and, accordingly, the type of converter, which is necessary in this case with a change in the parameters of the weight of the alloy.

Transistor induction furnace widely used for metallurgical processing. With its help, parts in blacksmithing are heated, metal objects are hardened. Crucibles in transistorized furnaces are made of ceramic or graphite, the former being designed to melt ferromagnetic metals such as cast iron or steel. Graphite is set to melt brass, copper, silver, bronze and gold. Glass and silicon are melted on them. Aluminum melts well with cast iron or steel crucibles.

What is the lining of induction furnaces

Its purpose is to protect the furnace casing from the damaging effects of high temperatures. A side effect is the preservation of heat, therefore, increases the efficiency of the process.

The crucible in the design of the induction furnace is made in one of the following ways:

• extraction method in small furnaces;
• in a rammed way from refractory material in the form of masonry;
• combined, combining ceramics and a buffer layer lining between the masonry and the indicator.

The lining is made of quartzite, corundum, graphite, fireclay graphite, magnesite. All these materials are mixed with additives that improve lining characteristics, reduce volume changes, improve sintering, and increase the layer's resistance to aggressive materials.

To select one or another lining material take into account a number of related conditions, namely, the type of metal, the price and refractory properties of the crucible, the service life of the composition. Properly selected composition of the lining should provide the technical requirements for the process:

• obtaining high quality ingots;
• the largest number of full-fledged melting without repair work;
• safe work of specialists;
• stability and continuity of the melting process;
• obtaining high-quality material using an economical amount of resources;
• application for lining common materials at a low price;
• minimal impact on the environment.

The use of induction furnaces allows you to get alloys and metals of excellent quality with a minimum content of various impurities and oxygen, which increases their use in complex areas of production.

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Unlike industrial equipment, a homemade metal melting furnace is a compact fixture. On such portable equipment, it is possible to smelt, harden or melt non-ferrous metals.

The furnace for melting metal is a body made of fireclay bricks. The binding element is clay. The fire chamber is intended for burning of coal. A hole is provided at the bottom through which air is blown into the ashes. Below is a cast-iron grate, which is called a grate. Coke or coal is laid out on it. It can be removed from the old furnace. Sometimes a refractory brick, when forming the body, is laid on the edge. The finished structure is fastened outside with a metal belt.

The furnace for remelting metals must have a crucible. It can be an enameled or cast iron cauldron. The location of the crucible is next to the burning coke. In order to improve the blowing, a fan is installed nearby. The equipment is used for steel smelting, but can be used as an iron smelting furnace.

Electric furnaces for metal melting

The basis of such a furnace is asbestos, which can be replaced with tiles. Do-it-yourself electrodes installed in the melting furnace must have a voltage of 25 V.

They are made in the following order:

• They are machined from the brushes of an electric motor.
• The assembly drilled holes 6 mm.
• They pass a wire with a cross section of 5 mm.
• A nail is driven in to secure the wiring.
• In order to improve contact with graphite, a file, notches are made.

As a heat insulator, mica is laid out inside the furnace. When connecting to the network, a step-down transformer must be used. After manufacturing, the furnace turns on and runs for some time in idle mode.

Muffle furnace

Muffle furnaces are often used for heat treatment of parts. Such equipment is characterized by a large temperature range, from 20 to 1000 degrees.

The muffle furnace for metal hardening works on different types of energy. However, at home it is better to use a unit that runs on electricity. Hardening is carried out in the furnace muffle.

A do-it-yourself muffle furnace is made in several stages:

• The muffle is made from fireclay bricks. Due to the round shape of the furnace body, their corners are bevelled. Grooves are selected in each brick, where the spiral is being laid.
• If the muffle furnace for melting is made from an oven, then inside it is lined with fire-resistant bricks. Grooves for the spiral are cut in the masonry.
• The chamber, made of refractory bricks, is placed in a case made of steel. The bottom is insulated. The gap between the side walls of the chamber and the housing is 4 cm, where the insulation is inserted. The top consists of 2 layers of metal and insulation.
• Holes are drilled in the case, and through them the ends of the spiral are brought out, which are connected to the network cable.
• In the case of using an oven, a heater is not required. It's already included in it.

aluminum smelting

Making an aluminum melting furnace with your own hands is a real thing. In industrial production, units with the name - carousel type furnaces - are very expensive.

To understand how to make an aluminum melting furnace, you need to understand their principle of operation. There are several types where non-ferrous metal is melted.

mini oven

A car disk is taken and buried in the ground so that the upper cut does not protrude. A hole for the pipe is made in the middle. One end is passed into the hole, and the other is brought out. A cooler is put on it to pump air. The smelter is filled with coals and aluminum scrap. Air is supplied and the temperature rises.

metal tank

You can make an aluminum furnace from a metal tank. For example, top-loading washing machine bodies. The interior of the structure is lined with refractory bricks. An air supply pipe is mounted below. Thus, portable equipment is obtained.

From a bottle

One of the unusual ways in which aluminum is melted. Nichrome wire is wound around the bottle. Previously, the surface of the bottle is lubricated with oil. A mixture of liquid glass and clay is applied on top. Drying is carried out within a week. Then another layer of wire is wound and clay is applied. After 7 days, the bottle is removed and only the heat-resistant shell remains. Voltage is connected to the ends of the wire for incandescent nichrome, and raw materials are loaded into the hearth.

Lead smelting

The lead smelting electric furnace consists of the following elements:

• A round casing made of stainless steel, inside of which a heater is laid. It is attached to the wall with brackets.
• An industrial TEN is supplied from below.
• At the top is a rotary valve.
• The sensor, which is located at a distance of 3 cm from the bottom.
• The temperature controller is on the side.

By setting the regulator to a certain temperature, we warm up the device. The lead inside melts. At the end of the melt, a mold is brought under the bottom and the valve opens. Molten lead fills the interior of the mold.

Copper smelting

At home, foam concrete can be used to melt copper. 2 cylinders are cut from such material, with a diameter of 100 mm. The height of one is 100 mm, and the second is 15. Putting one on top of the other, a hole with a diameter of 15 mm is drilled in the middle. In the larger cylinder, in the middle, a hole is made in the form of a funnel to a depth of 85 mm. In the middle of the cylinder, on the outside, a groove is cut and a wire tie is carried out. It is needed so that the part does not fall apart from the temperature.

On the gas stove, an adapter is placed. A larger cylinder is placed on top so that the conical funnel is directed upwards. From above it is covered with a small cylinder with a hole. Lighting the burner, lower a piece of copper rod into a small hole until it stops against the wall of the funnel. After a minute, the rod will melt.

Smelting gold and silver

A gold melting furnace is easy to make at home. It is also applicable to the melting of silver.

The order of work is as follows:

• A fireclay brick is taken and cut into 2 parts. With a Pobedite drill with a diameter of 48 mm, a through hole is made in one half, in the middle. And in the second hole is drilled at half the height.
• A spiral is drawn through the hole and both halves are pulled together with bolts, holes for which are drilled from the sides.
• A graphite crucible is placed on top.
• A metal frame is made and both halves are inserted into it.
• All side gaps are covered with clay.
• A voltage is applied to the output ends of the spiral.
• Pieces of gold or silver are thrown into the crucible.
• During the heating process, non-ferrous metal is melted.

Making furnaces for melting metal with your own hands is a complex process, but doable. To do this, you need to study the characteristics of the types of equipment. Decide which of them is most preferable to given conditions. The production costs will quickly pay for themselves.

An induction furnace is often used in the field of metallurgy, so this concept is well known to people who are more or less connected with the process of smelting various metals. The device allows you to convert electricity generated by a magnetic field into heat.

Such devices are sold in stores at a fairly high price, but if you have minimal skills in using a soldering iron and can read electronic circuits, then you can try to make an induction furnace with your own hands.

A homemade device is unlikely to be suitable for complex tasks, but it will cope with basic functions. You can assemble the device on the basis of a working welding inverter from transistors, or on lamps. The most productive in this case is the device on the lamps due to the high efficiency.

The principle of operation of the induction furnace

The heating of the metal placed inside the device occurs by the transition of electromagnetic pulses into heat energy. Electromagnetic impulses are produced by a coil with turns of copper wire or pipe.

Scheme of the induction furnace and heating schemes

When the device is connected, an electric current begins to pass through the coil, and an electric field appears around it, changing its direction over time. For the first time, the performance of such an installation was described by James Maxwell.

The object to be heated must be placed inside the coil or close to it. The target object will be pierced by a flux of magnetic induction, and a vortex-type magnetic field will appear inside. Thus, inductive energy will turn into heat.

Varieties

Furnaces on an induction coil are usually divided into two types depending on the type of construction:

• Channel;
• Crucible.

In the first devices, the metal for melting is located in front of the induction coil, and in the furnaces of the second type it is placed inside it.

You can assemble the oven by following the steps below:

1. We bend the copper pipe in the form of a spiral. In total, it is necessary to make about 15 turns, the distance between which should be at least 5 mm. Inside the spiral, a crucible should be freely located, where the smelting process will take place;
2. We make a reliable case for the device, which should not conduct electric current, and must withstand high air temperatures;
3. Chokes and capacitors are assembled according to the scheme indicated above;
4. A neon lamp is connected to the circuit, which will signal that the device is ready for operation;
5. A capacitor is also soldered to adjust the capacitance.

Heating use

Induction furnaces of this type can also be used for space heating. Most often they are used together with a boiler, which additionally produces cold water heating. In fact, designs are used extremely rarely due to the fact that, as a result of electromagnetic energy losses, the efficiency of the device is minimal.

Another drawback is based on the consumption of large amounts of electricity by the device during operation, because the device is classified as economically unprofitable.

System cooling

A self-assembled device must be equipped with a cooling system, since during operation all components will be exposed to high temperatures, the structure may overheat and break. Store-bought ovens are cooled with water or antifreeze.

When choosing a cooler for the home, preference is given to options that are most beneficial for implementation from an economic point of view.

For home ovens, you can try using a conventional blade fan. Pay attention to the fact that the device should not be too close to the oven, as the metal parts of the fan negatively affect the performance of the device, and can also open the vortex flows and reduce the performance of the entire system.

Precautions for using the device

When working with the device, you must adhere to the following rules:

• Some elements of the installation, as well as the metal that melts, are exposed to strong heat, as a result of which there is a risk of getting burned;
• When using a lamp oven, be sure to place it in a closed case, otherwise there is a high probability of electric shock;
• Before working with the device, remove all metal elements and complex electronic devices from the working area of ​​the device. The device should not be used by people who have a pacemaker installed.

The induction type metal melting furnace can be used in tinning and forming metal parts.

A home-made installation is easy to adjust to work in specific conditions by changing some settings. If you follow the indicated schemes when assembling the structure, as well as follow the elementary safety rules, a home-made device will practically not be inferior to store household appliances.