For many years, people have been smelting metal. Each material has its own melting point, which can be reached only with the use of special equipment. The first furnaces for melting metal were quite large and were installed exclusively in the workshops of large organizations. Today, a modern induction furnace can be installed in small workshops when setting up the production of jewelry. It is small, easy to handle and highly efficient.
Operating principle
melting knot induction furnace It is used for heating a wide variety of metals and alloys. The classic design consists of the following elements:
- Drain pump.
- Water cooled inductor.
- Frame in stainless steel or aluminium.
- Contact area.
- Hearth made of heat-resistant concrete.
- Support with hydraulic cylinder and bearing assembly.
The principle of operation is based on the creation of eddy induced Foucault currents. As a rule, during the operation of household appliances, such currents cause failures, but in this case they are used to heat the charge to the required temperature. Almost all electronics start to heat up during operation. This negative factor in the use of electricity is used to its full potential.
Device advantages
The induction melting furnace has been used relatively recently. Famous open-hearth furnaces are installed on production sites, blast furnaces and other types of equipment. Such a metal melting furnace has the following advantages:
It is the latter advantage that determines the spread of the induction furnace in jewelry, since even a small concentration of foreign matter can adversely affect the result.
Depending on the design features, floor and desktop induction furnaces are distinguished. Regardless of which option was chosen, there are several basic rules for installation:
The device may become very hot during operation. That is why there should not be any flammable or explosive substances nearby. In addition, technical fire safety near must be installed fire shield.
Only two types of furnaces are widely used: crucible and channel. They have similar advantages and disadvantages, the differences are only in the method of work used:
The crucible variety of induction furnaces is more popular. This is due to their high performance and ease of operation. In addition, a similar design, if necessary, can be made independently.
Homemade versions are quite common.. To create them you need:
- Generator.
- Crucible.
- Inductor.
An experienced electrician, if necessary, can make an inductor with his own hands. This structural element is represented by a winding of copper wire. The crucible can be purchased at the store, but a lamp circuit, a do-it-yourself battery of their transistors or a welding inverter is used as a generator.
Using a welding inverter
Do-it-yourself induction furnace for melting metal can be created using welding inverter as a generator. This variant is the most widely used since the efforts made concern only the manufacture of the inductor:
- Thin-walled copper tube is used as the main material. The recommended diameter is 8-10 cm.
- The tube is bent according to the desired pattern, which depends on the features of the body used.
- Between the turns there should be a distance of no more than 8 mm.
- The inductor is placed in a textolite or graphite case.
After the creation of the inductor and its placement in the housing, it remains only to install the purchased crucible in its place.
Such a circuit is rather complicated in execution, it involves the use of resistors, several diodes, transistors of various capacities, a film capacitor, copper wire with two various diameters and rings from chokes. Assembly recommendations are as follows:
The created circuit is placed in a textolite or graphite case, which are dielectrics. Scheme, involving the use of transistors, is quite difficult to implement. Therefore, it is necessary to undertake the manufacture of such a furnace only if there are certain work skills.
Furnace with lamps
V Lately lamp stoves are being created less and less, as they require care when handling. The applied circuit is simpler in comparison with the case of using transistors. Assembly can be carried out in several stages:
The lamps used must be protected from mechanical impact.
Equipment cooling
When creating an induction furnace with your own hands, the most problems arise with cooling. This is due to the following points:
- During operation, not only the molten metal is heated, but also some elements of the equipment. That is why effective cooling is required for long-term operation.
- The method based on the use of air flow is characterized by low efficiency. In addition, it is not recommended to install fans near the oven. This is due to the fact that metal elements can affect the generated eddy currents.
As a rule, cooling is carried out with water supply. Creating a water cooling circuit at home is not only difficult, but also uneconomical. Industrial versions of the furnace have an already built-in circuit, to which it is enough to connect cold water.
Safety
When using an induction furnace, certain safety precautions must be observed. Key recommendations:
When installing the equipment, consideration should be given to how the charge will be loaded and the molten metal will be extracted. It is recommended to allocate a separate prepared room for the installation of an induction furnace.
The induction furnace is no longer a novelty - this invention has existed since the 19th century, but only in our time, with the development of technology and the element base, it finally begins to enter everyday life everywhere. Previously, there were many questions in the intricacies of the operation of induction furnaces, not all physical processes were fully understood, and the units themselves had a lot of shortcomings and were used only in industry, mainly for melting metals.
Now, with the advent of powerful high-frequency transistors and cheap microcontrollers that have made a breakthrough in all areas of science and technology, truly efficient induction furnaces have appeared that can be freely used for domestic needs (cooking, heating water, heating) and even assemble hands.
Physical basis and principle of operation of the furnace
Fig.1. Scheme of the induction furnace
Before choosing or making an inductor heater, you should understand what it is. Recently, there has been an outbreak of interest in this topic, but few people have a complete understanding of the physics of magnetic waves. This gave rise to many misconceptions, myths and a lot of inefficient or unsafe homemade products. You can make an induction furnace with your own hands, but before that you should get at least basic knowledge.
The induction stove is based on the principle of electromagnetic induction. The key element here is the inductor, which is a high quality inductor. Induction furnaces are widely used for heating or melting electrically conductive materials, most often metals, due to the thermal effect of inducing an eddy electric current in them. The above diagram illustrates the design of this furnace (Fig. 1).
Generator G produces a variable frequency voltage. Under the action of its electromotive force, an alternating current I 1 flows in the inductor coil L. The inductor L together with the capacitor C is an oscillatory circuit tuned to resonance with the frequency of the source G, due to which the efficiency of the furnace is significantly increased.
In accordance with physical laws, an alternating magnetic field H arises in the space around the inductor L. This field can also exist in the air, but special ferromagnetic cores are sometimes used to improve performance, which have better magnetic conductivity compared to air.
The lines of force of the magnetic field pass through an object W placed inside the inductor and induce a magnetic flux F in it. If the material from which the workpiece W is made is electrically conductive, an induced current I 2 appears in it, closing inside and forming eddy induction flows. In accordance with the law of the thermal effect of electricity, eddy currents heat up the object W.
Making an inductive heater
An induction furnace consists of two main functional blocks: an inductor (a heating induction coil) and a generator (an alternating voltage source). The inductor is a bare copper tube coiled into a spiral (Fig. 2).
To make a do-it-yourself furnace with a power of not more than 3 kW, the inductor must be made with the following parameters:
- tube diameter - 10 mm;
- spiral diameter - 8-15 cm;
- the number of turns of the coil - 8-10;
- the distance between the turns is 5-7 mm;
- the minimum gap in the screen is 5 cm.
Adjacent turns of the coil must not be allowed to touch, keep the specified distance. The inductor must not come into contact with the protective screen of the furnace in any way, the gap between them must not be less than the specified one.
Generator manufacturing
Fig.3. Scheme on lamps
It is worth noting that an induction furnace for its manufacture requires at least average radio engineering skills and abilities. It is especially important to have them to create the second key element - a high-frequency current generator. Neither assembling nor using a do-it-yourself oven will work without this knowledge. Moreover, it can be life-threatening.
For those who undertake this business with knowledge and understanding of the process, there are various ways and schemes by which an induction furnace can be assembled. When choosing a suitable generator circuit, it is recommended to abandon options with a hard emission spectrum. These include the widespread scheme using a thyristor key. High-frequency radiation from such a generator is capable of creating powerful interference for all surrounding radio devices.
Since the middle of the 20th century, an induction furnace assembled on 4 lamps has enjoyed great success among radio amateurs. Its quality and efficiency are far from the best, and radio tubes are difficult to access nowadays, however, many continue to assemble generators according to this scheme, since it has a great advantage: a soft, narrow-band spectrum of the generated current, due to which such a furnace emits a minimum of interference and as safe as possible (Fig. 3).
The operating mode of this generator is set using a variable capacitor C. The capacitor must be with an air dielectric, the gap between its plates must be at least 3 mm. The diagram also contains a neon lamp L, which serves as an indicator.
Scheme of a universal generator
Modern induction furnaces operate on more advanced elements - microcircuits and transistors. The universal scheme of a push-pull generator, which develops power up to 1 kW, is enjoying great success. The principle of operation is based on an independent excitation generator, while the inductor is switched on in the bridge mode (Fig. 4).
Advantages of a push-pull generator assembled according to this scheme:
- The ability to work on the 2nd and 3rd mode in addition to the main one.
- There is a surface heating mode.
- Control range 10-10000 kHz.
- Soft spectrum of radiation in the entire range.
- Does not need additional protection.
Frequency tuning is carried out using a variable resistor R 2 . The operating frequency range is set by capacitors C 1 and C 2 . The interstage matching transformer must be with a ring ferrite core with a cross section of at least 2 sq.cm. The winding of the transformer is made of enameled wire with a cross section of 0.8-1.2 mm. Transistors must be seated on a common radiator with an area of \u200b\u200b400 sq. Cm.
Conclusion on the topic
The electromagnetic field (EMF) emitted by the induction furnace affects all the conductors around. It also affects the human body. The internal organs under the action of EMF are evenly warmed up, the overall body temperature rises throughout the entire volume.
Therefore, when working with the oven, it is important to observe certain precautions in order to avoid negative consequences.
First of all, the generator housing must be shielded with a casing made of galvanized iron sheets or mesh with small cells. This will reduce the radiation intensity by 30-50 times.
It should also be borne in mind that in the immediate vicinity of the inductor, the energy flux density will be higher, especially along the winding axis. Therefore, the induction coil must be placed vertically, and it is better to observe the heating from afar.
Induction melting is a process widely used in ferrous and non-ferrous metallurgy. Melting in induction heating devices is often superior to fuel-fired melting in terms of energy efficiency, product quality and production flexibility. These pre-
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properties are due to the specific physical characteristics of induction furnaces.
During induction melting, there is a translation solid material into the liquid phase under the influence of an electromagnetic field. As in the case of induction heating, heat is generated in the melted material due to the Joule effect from the induced eddy currents. The primary current passing through the inductor creates an electromagnetic field. Regardless of whether the electromagnetic field is concentrated by magnetic circuits or not, the coupled inductor-load system can be represented as a transformer with a magnetic circuit or as an air transformer. The electrical efficiency of the system is highly dependent on the field-influencing characteristics of the ferromagnetic structural elements.
Along with electromagnetic and thermal phenomena, electrodynamic forces play an important role in the process of induction melting. These forces must be taken into account, especially in the case of melting in powerful induction furnaces. The interaction of induced electric currents in the melt with the resulting magnetic field causes a mechanical force (Lorentz force)
Pressure Melt flows
Rice. 7.21. The action of electromagnetic forces
For example, the force-induced turbulent motion of the melt is of great importance both for good heat transfer and for the mixing and adhesion of non-conductive particles in the melt.
There are two main types of induction furnaces: induction crucible furnaces (ITF) and induction channel furnaces (IKP). In ITP, the melted material is usually loaded in pieces into the crucible (Fig. 7.22). The inductor covers the crucible and the melted material. Due to the absence of a concentrating field of the magnetic circuit, the electromagnetic connection between
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inductor and loading strongly depends on the wall thickness of the ceramic crucible. To ensure high electrical efficiency, the insulation should be as thin as possible. On the other hand, the lining must be thick enough to withstand thermal stresses and
metal movement. Therefore, a compromise should be sought between the electrical and strength criteria.
Important characteristics of induction melting in IHF are the movement of the melt and the meniscus as a result of the action of electromagnetic forces. The movement of the melt ensures both uniform temperature distribution and homogeneous chemical composition. The mixing effect at the melt surface reduces material losses during reloading of small batches and additives. Despite the use of cheap material, the reproduction of a melt of constant composition ensures high casting quality.
Depending on the size, the type of material to be melted and the field of application, ITPs operate at an industrial frequency (50 Hz) or medium
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them at frequencies up to 1000 Hz. The latter are becoming increasingly important due to their high efficiency in the smelting of cast iron and aluminium. Since the movement of the melt at constant power is attenuated with increasing frequency, higher specific powers become available at higher frequencies and, as a result, greater productivity. Due to the higher power, the melting time is shortened, which leads to efficiency increase process (compared to furnaces operating at industrial frequency). Taking into account other technological advantages, such as flexibility in changing the materials being smelted, medium frequency IHFs are designed as the powerful melting units that currently dominate the iron foundry. Modern high-power medium-frequency ITPs for iron smelting have a capacity of up to 12 tons and a power of up to 10 MW. Industrial frequency ITPs are designed for larger capacities than medium-frequency ones, up to 150 tons for iron smelting. Intensive mixing of the bath is of particular importance in the smelting of homogeneous alloys, such as brass, so industrial frequency ITPs are widely used in this area. Along with the use of crucible furnaces for melting, they are also currently used for holding liquid metal before pouring.
In accordance with the energy balance of ITP (Fig. 7.23), the level of electrical efficiency for almost all types of furnaces is about 0.8. Approximately 20% of the original energy is lost in the inductor in the form of Joe - heat. The ratio of heat losses through the walls of the crucible to that induced in the melt electrical energy reaches 10%, so the total efficiency of the furnace is about 0.7.
The second widespread type of induction furnaces are ICP. They are used for casting, holding and, especially, melting in ferrous and non-ferrous metallurgy. The ICP generally consists of a ceramic bath and one or more induction units (Fig. 7.24). V
principle, the induction unit can be represented as a transform-
The operating principle of the ICP requires a permanently closed secondary loop, so these furnaces operate with the liquid residue of the melt. Useful heat is generated mainly in the channel having a small cross section. The circulation of the melt under the action of electromagnetic and thermal forces ensures sufficient heat transfer to the bulk of the melt in the bath. Until now, ICPs have been designed for industrial frequency, but research work carried out for higher frequencies. Thanks to compact design furnace and very good electromagnetic coupling, its electrical efficiency reaches 95%, and the overall efficiency - 80% and even 90%, depending on the material being melted.
In accordance with the technological conditions in different areas of application, ICPs are required various designs induction channels. Single-channel furnaces are mainly used for holding and casting,
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rarer steel melting at installed capacities up to 3 MW. For melting and soaking non-ferrous metals, two-channel designs are preferred for better energy utilization. In aluminum smelters, the channels are straight for easy cleaning.
The production of aluminium, copper, brass and their alloys is the main field of application of the ICP. Today, the most powerful ICPs with a capacity of
up to 70 tons and power up to 3 MW are used for aluminum smelting. Along with high electrical efficiency in aluminum production, low melt losses are very important, which predetermines the choice of ICP.
Promising applications of induction melting technology are the production of high purity metals such as titanium and its alloys in cold crucible induction furnaces and the melting of ceramics such as zirconium silicate and zirconium oxide.
When melting in induction furnaces, the advantages of induction heating are clearly manifested, such as high energy density and productivity, homogenization of the melt due to stirring, accurate
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energy and temperature control, as well as ease of automatic process control, ease of manual control and great flexibility. High electrical and thermal efficiencies, combined with low melt losses and therefore savings in raw materials, result in low specific energy consumption and environmental competitiveness.
The superiority of induction melting devices over fuel ones is constantly increasing due to practical research, supported by numerical methods for solving electromagnetic and hydrodynamic problems. As an example, we can note the internal coating with copper strips of the steel casing of the ICP for copper melting. The reduction of losses from eddy currents increased the efficiency of the furnace by 8%, and it reached 92%.
Further improvement in the economic performance of induction melting is possible through the use of modern technologies controls such as tandem or dual power control. Two tandem ITPs have one power source, and while melting is in progress in one, the molten metal is held in the other for pouring. Switching the power source from one oven to another increases its utilization. A further development of this principle is dual feed control (Fig. 7.25), which ensures continuous simultaneous operation of furnaces without switching using special process control automation. It should also be noted that an integral part of the smelting economics is the compensation of the total reactive power.
In conclusion, to demonstrate the advantages of energy- and material-saving induction technology, fuel and electrothermal methods of aluminum smelting can be compared. Rice. 7.26 shows a significant reduction in energy consumption per ton of aluminum when smelting in
Chapter 7
□ loss of metal; Shch melting
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induction channel furnace with a capacity of 50 tons. The final energy consumed is reduced by about 60%, and the primary energy by 20%. At the same time, CO2 emissions are significantly reduced. (All calculations are based on typical German energy conversion and CO2 emissions from mixed power plants). The results obtained emphasize the special effect of metal losses during melting associated with its oxidation. Their compensation requires a large additional expenditure of energy. It is noteworthy that in the production of copper, metal losses during melting are also large and should be taken into account when choosing one or another melting technology.
A household induction stove can easily heat a home. In industry, these devices are involved in the smelting of various metals. Additionally, they can participate in the heat treatment of parts, as well as their hardening. The main advantage of an induction type oven is its ease of use. In addition, they are easy to maintain and do not require periodic inspections, which is very important.
There is absolutely no need to allocate a separate room for the installation of this device. The performance of these devices is very good. This is largely due to the fact that there are no parts in the design that are subject to mechanical wear. In general, induction-type furnaces are safe for human health and do not pose a danger during operation.
How it works?
The operation of the induction furnace begins with the supply of alternating current to the generator. At the same time, it passes through a special inductor, which is located inside the structure. Next, a capacitor is used in the device. Its main task is to form an oscillatory circuit. In this case, the entire system is configured for operating frequency. The inductor in the furnace creates an alternating magnetic field. At this time, the voltage in the device rises to 200 V.
To complete the circuit, the system has a ferromagnetic core, however, it is not installed on all models. Subsequently, the magnetic field interacts with the workpiece and creates a powerful flux. Next, the electrically conductive element is induced and a secondary voltage occurs. This creates an eddy current in the capacitor. According to the Joule-Lenz law, he gives his energy to the inductor. As a result, the workpiece in the furnace heats up.
Homemade induction type ovens
Do-it-yourself induction furnace is made strictly according to the drawings in compliance with safety rules. The body of the device should be selected from aluminum alloy. A large platform should be provided at the top of the structure. Its thickness must be at least 10 mm. Most often, a steel template is used to stuff the crucible. To drain the molten metal, a lining cavity in the form of a spout is required. In this case, the structure must have a pad for stuffing.
For sections, an insulating stand is installed above the template. Directly below it will be a hinged support. In order to cool the inductor, the furnace must have a fitting. Voltage is supplied to the device through the bridge, which is located at the bottom of the device. To tilt the container, a do-it-yourself induction furnace must have a separate gearbox. In this case, it is best to make a handle so that it is possible to merge the metal manually.
Furnaces of the company "Termolit"
Induction furnaces for melting metal of this brand have an acceptable converter power. At the same time, the capacity of the cameras in the models can vary greatly. The average metal melting rate is 0.4 t/h. At the same time, the nominal voltage of the supply network fluctuates around 0.3 V. The water consumption in an induction type furnace depends on the cooling system. Usually this parameter is 10 cubic meters / h. At the same time, the specific power consumption is quite high.
Characteristics of the furnace "Termolit TM1"
This melting furnace (induction) has a total capacity of 0.03 tons. At the same time, the converter power is only 50 kW, and the average melting speed is 0.04 tons per hour. The voltage of the supply medium must be at least 0.38 V. The water consumption for cooling in this model is negligible. This is largely due to the low power of the device.
Of the shortcomings, a high power consumption should be highlighted. On average, approximately 650 kW are consumed per hour of operation of the furnace. The frequency converter in this model has a class "TPCh-50". In general, "Termolit TM1" is an economical equipment, but with poor performance.
Induction furnace "TG-2"
Induction melting furnaces of the TG series are produced with a chamber capacity of 0.6 tons. The rated power of the device is 100 kW. At the same time, it is possible to melt 0.16 tons of non-ferrous metals per hour of continuous operation. This model is powered by a network with a voltage of 0.3 V.
The water consumption of the TG-2 furnace of the induction type is quite significant and, on average, up to 10 cubic meters liquids. All this is due to the need for intensive cooling of the gearbox. The positive side is moderate power consumption. Typically, up to 530 kW of electricity is consumed per hour of operation. The frequency converter in the "TG-2" model is installed in the "TPCh-100" class.
Furnaces "Thermo Pro"
The main modifications of the equipment from this company are induction melting furnaces SAT 05, SAK-1, and SOT 05. Their average nominal melting point is 900 degrees. At the same time, the power of the devices fluctuates around 150 kW. In addition, it should be noted their good performance. For an hour of work of non-ferrous metals, 80 kg can be melted. At the same time, many Thermo Pro models are made for narrowly targeted use. Some of them are designed exclusively for working with aluminum, while other modifications are used to melt lead or tin.
Modification "SAT 05"
This induction furnace is designed for aluminum melt. The power of this device is exactly 20 kW. At the same time, up to 20 kg of metal can be passed per hour of work. The capacity of the chamber in the "SAT 05" model is 50 kg, and the frequency converter is of the "TFC" class.
Batteries in the device are installed capacitor type. In the lower part of the structure, the manufacturer installed a special water-cooled cable. The control panel in this model is available. Among other things, it should be noted a large set of furnace "SAT 05". It includes all mounting accessories, as well as operating documents.
Parameters of the furnace "SAK-1"
This induction furnace is most commonly used for melting lead as well as tin. In some cases, it is allowed to lay copper, but the performance drops significantly. The average melting temperature fluctuates around 1000 degrees, this device has a power of 250 kW. For an hour of continuous operation, it is possible to skip up to 400 kg of non-ferrous metals. At the same time, the capacity of the equipment allows loading up to 1000 kg of material. The supply voltage is 0.3 kV.
Water consumption for cooling the SAK-1 model is insignificant. The oven consumes approximately 10 cubic meters of liquid per hour. The specific power consumption is also small and amounts to 530 kW. The frequency converter in this design is provided for the brand "TPC-400". In general, the SAK-1 model turned out to be economical and easy to use.
Overview of the "SAK 05" model
Induction furnaces for melting metal "SAK 05" have a large capacity - 0.5 tons. At the same time, the power of the supply converter is 400 kW. The working speed of melting in this furnace is quite high. The rated voltage of the device is 0.3 kV. For an hour of water operation, approximately 11 cubic meters are consumed to cool the system. It should also be noted that the power consumption is considerable and amounts to 530 kW. The frequency converter in the device has a class "TPCh-400". At the same time, it is able to pump the maximum temperature up to 800 degrees. The induction furnace "SAK 05" is designed exclusively for melting aluminum and bronze. The heat exchange cabinet is installed by the manufacturer brand "IM". It should also be noted convenient remote control. There is an alarm system and a hydraulic station in the system.
Among other things, a set of turbo tires and mounting accessories are included as standard. In general, the SAK 05 model turned out to be quite secure, and you can use it without risk to health. This was largely achieved through rods that are mounted on hydraulic cylinders. At the same time, the metal practically does not splash. Direct frequency adjustment during operation occurs in automatic mode. Capacitors are used in this medium voltage model.
The heating of bodies with the help of an electromagnetic field arising from exposure to an induced current is called induction heating. Electrothermal equipment, or induction furnace, has different models designed to perform tasks for various purposes.
Design and principle of operation
By technical specifications the device is part of a plant used in the metallurgical industry. The principle of operation of an induction furnace depends on alternating current , the power of the installation is formed by the purpose of the device, the design of which includes:
- inductor;
- frame;
- melting chamber;
- vacuum system;
- mechanisms for moving the object of heating and other devices.
The modern consumer market has a large number of models of devices operating according to the eddy current generation scheme. The principle of operation and design features of an industrial induction furnace allows you to perform a number of specific operations related to the melting of non-ferrous metal, heat treatment of metal products, sintering of synthetic materials, cleaning of precious and semi-precious stones. Appliances are used for disinfection of household items and space heating.
The work of the IP (induction furnace) is to heat the objects placed in the chamber with eddy currents emitted by an inductor, which is an inductor made in the form of a spiral, figure eight or trefoil with a winding wire of large cross-section. An inductor powered by alternating current creates a pulsed magnetic field, the power of which varies in accordance with the frequency of the current. An object placed in a magnetic field heats up to the boiling point (liquid) or melting point (metal).
Installations operating with the help of a magnetic field are produced in two types: with a magnetic conductor and without a magnetic circuit. The first type of devices has an inductor in the design, enclosed in a metal case, which ensures a rapid increase in temperature inside the object being processed. In furnaces of the second type, the magnetotron is located outside the installation.
Features of induction appliances
The master also requires skills in the design and installation of electrical appliances. The safety of the device of individual assembly lies in a number of features:
- equipment capacities;
- operating pulse frequency;
- generator power;
- eddy losses;
- hysteresis losses;
- heat transfer intensity;
- lining method.
Channel furnaces got their name for the presence in the space of the unit of two holes with a channel forming a closed loop. By structural features the device cannot work without a circuit, thanks to which liquid aluminum is in continuous motion. If the manufacturer's recommendations are not followed, the equipment switches off spontaneously, interrupting the melting process.
According to the location of the channels, induction melting units are vertical and horizontal with a drum or cylindrical chamber. The drum furnace, in which cast iron can be smelted, is made of sheet steel. Swivel mechanism Equipped with driven rollers, two speed motor and chain drive.
Liquid bronze is poured through a siphon located on the end wall, additives and slags are loaded and removed through special openings. The output of finished products is carried out through a V-shaped drain channel made in the lining according to a template, which is melted in the working process. The winding and core are cooled by air mass, the body temperature is regulated by water.
