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Induction melting furnace technical information is all here, all you want to know is here!

Time: 2021-08-14

Induction melting furnace technical information is all here, all you want to know is here!

A. How to increase the melting speed of the induction melting furnace?

1.   Increase the power of the intermediate frequency power supply of the induction melting furnace .

2.   Choose a reasonable charge size and correct feeding method.

3.   Appropriate molten iron tapping temperature.

B. What is the price of induction melting furnace ?

Calculated according to the power of the power supply of the induction melting furnace and the volume of the electric furnace. Different configurations have different prices.

C , induction melting furnace lining material, how to choose?

1. induction melting furnace lining materials are divided into acid lining materials, alkaline lining materials, neutral lining materials, coil mortar, root melting material, induction melting furnace tonnage, and product molding temperature. It is important to choose suitable lining materials. work.

2. The induction melting furnace is a steel melting furnace that uses alkaline lining materials, mainly fused magnesia. The induction melting furnace is an iron melting furnace that uses acidic lining materials, which are refractory materials for quartz coreless induction furnaces, and the material is acidic.

D , quickly and correctly select the " induction melting furnace ," a good way of

1. Selection of Transformer Capacity for Induction Melting Furnace

The value of the transformer capacity = the value of the power supply of the induction melting furnace x 1.2

The transformer is a rectifier transformer. In order to reduce the interference of harmonics, try to use a dedicated machine as much as possible, that is, an induction melting furnace is equipped with a rectifier transformer.

2. Selection of the incoming line voltage of the induction melting furnace

For induction melting furnaces below 1000KW , the intermediate frequency power supply generally adopts three-phase five-wire 380V , 50HZ industrial power. For induction melting furnaces above 1000KW , it focuses on the use of 660V incoming line voltage .

3 . The capacity requirements determine how much tonnage selected induction melting furnace.

According to the weight of a single piece and the weight of the molten iron required for each working day, the capacity of the induction melting furnace can be determined .

The standard tonnage is as follows:

1T induction melting furnace

500kg induction melting furnace

2T induction melting furnace

3T induction melting furnace

5T induction melting furnace

4 . Furnace selected structure

The aluminum alloy structure supply melting furnace with the reducer as the tilting furnace is commonly known as the aluminum shell furnace. A steel structure induction melting furnace with a hydraulic cylinder as a tilting furnace is commonly known as a steel shell furnace. The steel shell furnace is a steel structure , and the aluminum shell furnace shell is made of aluminum alloy .

E , induction melting furnace induction loop overhaul Notes

There are holes in the induction coil, generally the size of a soybean or a longer one, can be brazed and welded directly, and a larger piece of copper should be patched, and a copper electrode can be used to weld it with gas welding. After that, test the water pressure and there is no leakage point !

F. Operating procedures of induction melting furnace

1 . Before starting the induction melting furnace, inform the operator of the intermediate frequency unit to start the unit. At the same time, check whether the furnace body, cooling water system, intermediate frequency power switch, furnace tilting machinery and running track of the lifting bag are normal, and whether the trench cover is defective and covered. If there is any problem, it should be eliminated before starting the furnace.

2 . When opening the furnace, you need to put the charge into the furnace first, and then turn on the intermediate frequency power switch after opening the cooling water. When the furnace is shut down, the intermediate frequency unit can be notified to stop only after the intermediate frequency power supply is disconnected. The cooling water should continue to be maintained for 15 minutes.

3 . The charge shall not be mixed with airtight containers, pipes or other explosive materials. The charge must be dry, without water, ice or snow. When loading the furnace material, do not hit it with a hammer, and should be gently placed and tapped to avoid damage to the furnace. When the furnace burning loss and thinning exceed the regulations, the furnace should be shut down for repairs.

4 . Tools should be placed in the designated place, and should be baked and dried before use.

5 . When adding alloy material to alloy steel, it should be clamped with pliers after preheating, and added slowly and in batches. When adding, the face of the operator should avoid the furnace mouth.

G. The only good way to increase the power of the induction melting furnace

In the case of the same supply voltage, the power can be increased by reducing the impedance of the load, or increasing the inverter angle can also increase the power, but it must be considered that increasing the inverter angle will reduce the power factor of the induction melting furnace . The only good way to increase the power of an induction melting furnace is to reduce the impedance is to increase the number of resonant capacitors, but the reduction of the resonant frequency of the furnace must be considered. In short, these two methods are used. Experiment and tune, and give consideration to as much as possible.

H. Which metal materials are more suitable for smelting in an induction melting furnace?

The induction melting furnace uses an intermediate frequency power supply to establish an intermediate frequency magnetic field, which generates induced eddy currents inside the ferromagnetic material and generates heat, so as to achieve the purpose of heating the material. The intermediate frequency heating furnace adopts 200-2500Hz intermediate frequency power supply for induction heating, smelting and heat preservation. The induction melting furnace is mainly used for smelting carbon steel, alloy steel, special steel, and can also be used for smelting and heating of non-ferrous metals such as copper and aluminum . The equipment is small in size . , Light weight, high efficiency, low power consumption, fast melting and heating, easy control of furnace temperature, and high production efficiency.

The induction melting furnace mainly adopts the principle of induction heating, which is suitable for heating metal materials with high resistivity. ( The resistivity of commonly used metal materials at 20 degrees is : silver (1.6 density ), copper (1.7), gold (2.4), aluminum (2.7), zinc (5.2), tungsten (5.7), iron (9.7), platinum (10.6), tin (11), lead (21), etc.). Generally, our common bearing thermal disassembly equipment is mainly used for heating steel, alloy, non-ferrous metals and other materials.

The I , aluminum 250KG induction melting furnace of the " 0.25 " What does it mean? 

It is the specification of the furnace body, namely the tonnage. Induction melting furnaces generally have 0.25T , 0.35T , 0.5T , 0.75T , 1T , 2T , 3T , 5T , 10T, etc.

The aluminum shell 250KG induction melting furnace is an intermediate frequency coreless induction melting furnace ( non-vacuum ) that uses a controllable silicon static intermediate frequency power supply for induction heating. It is used for smelting and heat preservation of non-ferrous metals such as copper, aluminum, and stainless steel . It is generally classified according to the furnace body capacity There are two types of aluminum shell structure and steel shell structure. The aluminum shell structure generally adopts a reducer as the power of the tilting furnace ( there are a few hydraulic tilting furnaces ) , and the steel shell structure generally adopts the hydraulic pressure as the power of the tilting furnace.

The main technical parameters

Power supply voltage three-phase 380V

Power frequency 50HZ

IF voltage 1000V

IF frequency 1500HZ

Working temperature 1600 ℃

Cooling water inlet pressure 0.15~0.2Mpa

J , 250KG induction melting furnace needs with little transformer ?

The power of the intermediate frequency power supply used in the 250KG induction melting furnace determines the power, the ordinary melting power is 160kW , and the fast melting 250kW . If you need it faster, you can increase the power to 360kW. Generally, foundries require fast melting, which is 250kW ( 1kW per kilogram of molten iron ), so you can consider 160-250 KVA transformers.

How to translate induction melting furnace in Japanese?


Reading: Intermediate Frequency Induction Furnace

Induction melting furnace English how translation?

Medium frequency induction furnace how to write in English

K. What parts are included in the complete set of induction melting furnace equipment ?

Including: intermediate frequency power supply and induction melting furnace body part, furnace body part including steel shell and aluminum shell furnace body , furnace tilting device including reducer tilting furnace or hydraulic tilting furnace mechanism and water cooling system such as closed-loop cooling tower .

Induction melting furnace is particularly suitable for steel, cast iron, and copper, and other nonferrous metals and alloys for aluminum melting and holding liquid metal, adaptability to strong charge, for intermittent operation, the furnace structure and usage frequency similar centerless Induction furnace.

Composition of induction melting furnace : Induction furnace is usually composed of four parts: power supply, furnace body (mainly induction coil and crucible made of refractory material in induction coil ), capacitor bank (used to improve power factor ), control and operating system.

1 . Induction melting furnace body part

(1) The induction coil of the induction furnace: the induction coil is the heart of the induction furnace. The electromagnetic energy is converted into heat energy through the induction coil, and the metal charge in the crucible is melted. A rectangular copper tube is wound into a multi-turn coil with spiral shape. High-strength insulating paint is sprayed and wrapped with insulating tape, refractory mortar is also applied between the turns of the induction melting furnace , and a water-cooled ring is arranged above and below the induction loop.

(2) The magnetic yoke of the induction furnace: The magnetic yoke is made of high-quality silicon steel sheets, distributed around the periphery of the induction coil, and acts as a support frame. At the same time, it also restrains the external flux leakage of the induction coil to prevent the metal components from heating up.

(3) Water-cooled cable for induction furnace: due to frequent furnace tilting, the flexible wire of the water-cooled cable may break, and the connection bolts at the terminal end may be loosened, which may cause current imbalance. Generally, the life of the water-cooled cable is three years according to the number of tilts. It needs to be replaced after three years. If the bolts change color, they need to be updated and tightened in time.

(4) Induction furnace lining: The induction furnace has high temperature during production, and the furnace temperature changes greatly, and it is also subjected to slag erosion and electromagnetic stirring. High temperature molten iron directly washes the crucible lining. The furnace lining is easily damaged, and the cost of building the furnace is high, and the induction is prolonged. The service life of furnace lining and reducing the frequency of furnace construction are very important to reduce costs.

(5) Crucible leakage alarm device of induction furnace: In order to ensure safe production, prevent the occurrence and expansion of furnace leakage accidents, help to judge the use of furnace lining and prolong furnace age, it is necessary to set up a crucible leakage alarm system. Generally, a direct current alarm device is used to install the stainless steel wire bottom electrode (first electrode) in contact with the molten iron and the stainless steel plate (mesh) side electrode (second electrode) between the induction loop of the furnace lining.

2 . Hydraulic system of induction melting furnace

It is composed of hydraulic device, console, tilting furnace hydraulic cylinder, furnace cover hydraulic cylinder, etc. The hydraulic system should be checked regularly for leakage. If it is found that the sealing ring should be replaced, all rotating parts should be regularly lubricated with lubricating oil. Until the oil overflows), otherwise it is very easy to cause damage.

3 . Water cooling system of induction melting furnace

Ensure the quality of the cooling water and regularly check for scale. If there is scale, it should be cleaned up immediately to ensure the cooling effect. Cooling water quality is generally required frequency furnace: the pH value of 6 ~ 9 , the hardness of <10mg equivalent / L , the total solids of not more than 250 mg of / L , the coolant temperature rise <25 deg.] C ; cooling water for a water supply IF : PH value is 7 ~ 8 , hardness <1.5mg equivalent /L , suspended solids: 50mg/L , resistivity >4000Ω·cm . The circulating water in the circulating pool should be tested regularly. When the hardness of the circulating water exceeds 2mg equivalent /L , the circulating water in the system should be emptied and replaced. The cooling water tower should be discharged regularly in exchange for new soft water to prevent clogging of pipes and nozzles, which will affect the cooling effect and the service life of the furnace lining.

4 . Electric control system of induction melting furnace

The main circuit and induction coil should be regularly cleaned of dust on the surface. Conductive metal dust in the foundry, iron beans splashed during tapping, etc. fall on the surface of the main copper bar or induction coil, which will cause its insulation capacity to decrease, resulting in discharge and ignition. Cause damage to electrical components. Can be blown off by compressed air without water. The connecting screws of the main circuit copper busbars also need to be checked and tightened regularly, otherwise, due to the increase in contact resistance, a large amount of heat will be generated at the connection and the insulation material will be carbonized and cause current leakage.

The choice of structure Generally speaking, according to the weight of a single piece and the weight of molten iron required for each working day, the capacity of the induction melting furnace can be determined , and then the power and frequency of the intermediate frequency power supply can be determined . Induction heating equipment is a non-standard product, and there is no standard. The general configuration in the industry is shown in the table below.


Steel shell furnace

Aluminum shell furnace

shell material

Steel structure

Aluminum structure

Tilting mechanism

Hydraulic cylinder


Hydraulic power station






Stove cover



Oven leak alarm



Energy consumption




10 years

4-5 years




L , induction melting furnace advantages :

Compared with power frequency centerless induction furnace, induction melting furnace has the following advantages.

(1) Under the same capacity, the input power of the induction melting furnace is high, which can be 2 to 3 times that of the industrial frequency furnace , which greatly improves the melting rate of the furnace and reduces the power consumption.

(2) There is no need for residual melt and large frit, which can be melted at any time, reducing power consumption.

(3) All or part of the melt can be poured each time it is out of the furnace, so the operation flexibility is greater.

(4) Convenient power reduction, which can adapt to different requirements for power during melting, heat preservation and baking.

(5) The operating frequency changes with the resonant frequency of the load circuit during operation, and the load circuit automatically maintains a higher power factor, without the need to increase or decrease the load capacitance like a power frequency furnace.

(6) The three-phase balance of the power frequency input terminal does not need to be equipped with an LC three-phase balance device like a power frequency furnace .

(7) Under the same output, the induction melting furnace has a small capacity, which greatly reduces the floor space, reduces infrastructure investment, and improves space utilization.

M , induction melting furnace maintenance :

The maintenance of the induction melting furnace is very important. It can discover all kinds of hidden dangers in time, avoid major accidents, extend the service life, ensure safe production, improve the quality of castings, and reduce costs. Regularly record the relevant electrical parameters, cooling water temperature and the temperature of the key parts of the furnace body (furnace bottom, furnace side, induction coil housing, copper bar, etc.), and the use of the electric furnace can be monitored at any time. Start the diesel generator regularly to ensure reliable operation.

1) Carry out regular maintenance, lubrication and tightening of the electric furnace according to the stipulated time (such as: use anhydrous compressed air to systematically remove dust from the induction coil, copper bar, electric control cabinet, etc.; lubricate the lubrication parts; tighten the bolts).

2) Observe the water pressure gauge, water temperature gauge and check the aging degree of the water delivery hose every day; regularly check the flow of each cooling water branch to ensure that the pipeline is not blocked and the pipe joints do not leak, especially the cooling water joints in the solid power cabinet. Water leakage is absolutely not allowed. If you find water leakage, you can tighten the clamp of the pipe joint or replace the clamp; regularly check the water storage in the water tower spray pool, expansion tank, power supply cabinet, and water tank, and replenish the water in time; Check the condition of the standby pump and use the standby pump every 3 to 5 days to ensure that the standby pump is absolutely reliable.

3) Check if the capacitor is leaking oil. If oil leaks at the capacitor terminal, use a wrench to tighten the nut at the bottom of the terminal.

4) Mid-term maintenance. Grind the AC inlet side porcelain insulators, brackets, rectifier diodes, brackets, capacitor porcelain insulators, IGBT (silicon controlled) main contact parts, inverter and intermediate frequency AC copper bars, etc. with ethanol ; replace the aging output of the electrical cabinet Water pipes, dredge the bottleneck of the water nozzle, IGBT (silicon controlled silicon) water cooling block, replace the AC copper bus insulation board, individual capacitors, etc.

N , the same type of induction melting furnaces why the price difference so much ? How to choose ?

The price of the induction melting furnace of the same model is very different, which is related to many factors such as the structure of the furnace, the selection of components, the technical content, after-sales service, and the quality.

1. The difference in material selection

Furnace shell and the yoke: some manufacturers often furnace shell weight . And insufficient thickness; the most important is to choose the furnace steel yoke, choose different types of furnace steel yoke, a large gap between the price (with Manufacturers use scrap, non-oriented, or even silicon steel sheets disassembled from scrap transformers to make yokes) 

Copper tubes and copper bars: The core of the melting furnace is the induction coil cold extruded copper tube and the cast copper tube. The effect and price are far different. T2 cold-extruded copper pipes with huge cross-section should be used . The surface insulation treatment of the copper pipes is electrostatic sprayed to achieve H -class insulation . Some manufacturers use cast copper or T3 copper pipes, which are poor in conductivity and easy to break and leak. Special attention should be paid 

Thyristor: The quality of the thyristor used by various manufacturers is generally uneven. The good quality thyristor has good temperature sensitivity, fast response and low failure rate. I choose with Xiangfan LMH SCR-known manufacturers, reliable quality and stable. 

Power cabinet: regular manufacturers use standard plastic-sprayed cabinet shells. Rather than the tin-painted cabinet shell. And the size specifications of the power cabinet are all standard. Irregular manufacturers supply cabinet has shrunk height . Width and thickness enough, and even some of the rest of the reactor outside the power cabinet. The regular manufacturer's intermediate frequency power supply is equipped with low-voltage switches inside, and there is no need for users to configure additional voltage switch cabinets. However, some irregular manufacturers do not have low-voltage switches installed inside their power supplies. Intangible increase in user costs.

Capacitor: reactive power compensation capacitance is the number of the main cabinet must be equipped with a sufficient amount, generally an amount of the compensation capacitor is the power value of the power of 18 is ---- 20 is fold namely: capacitive compensation amount ( Kvar ) = ( 20 is - 18 ) x power supply. And use capacitors from regular manufacturers.

Reactor: The main material of the reactor is silicon steel sheet. New products produced by regular manufacturers should be used instead of recycled second-hand silicon steel sheets.

 Water pipe clamps: There are a large number of water pipe connections in the complete equipment of the intermediate frequency melting furnace. Strictly speaking, stainless steel clamps should be used, and it is better to use copper slip knots, which are easy to install and disassemble, and do not require maintenance. It is especially suitable for water-cooled cables, which is conducive to current transmission and will not cause water leakage, and is safe and reliable. 

In addition to the above points, the selection of other components is also very important, such as inverter non-inductive capacitors, non-inductive resistors, water-cooled cables, connecting copper bars, water pipes, etc., which will affect the quality and price of the equipment. When choosing to buy, pay attention to, try to request the melting furnace manufacturer to provide the details of the main components and the manufacturer, not just compare the price and ignore the internal structure and quality of the equipment. Since the induction melting furnace is a non-standard product, first order and then manufacture, the quality of the furnace is closely related to the price.

O. What are the benefits of using induction melting furnaces for steelmaking ?

( 1 ) Although the induction melting furnace is also a high-power power-consuming device, its interference to the power grid is much smaller than that of an electric arc furnace;

( 2 ) In terms of environmental impact, the noise during the smelting process is low, and the emission of smoke, gas, dust and waste slag is relatively small;

( 3 ) In terms of resource utilization, furnace loading materials (including various alloying elements added) have less burning loss and higher yield. The amount of slag-making materials is much smaller, and no electrodes are used;

( 4 ) Due to the electromagnetic stirring effect in the metallurgical function, the composition of the molten steel is relatively uniform, the temperature of the molten steel is also relatively uniform, and the temperature control is relatively convenient, and there is no problem of carbon increase due to electrodes. Since there is no high temperature effect of the arc, there is no problem that nitrogen dissociates at high temperature and is easily absorbed by molten steel;

( 5 ) The investment in equipment is less, and the area occupied by the site is also relatively small;

( 6 ) It is easier to automate the operation

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