Refractory Lining Material For Induction Furnace

By Author: yanghuimin
Total Articles: 132
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Refractory materials for induction furnaces need to be selected according to the furnace type, furnace structure, type of steel to be smelted, smelting process and operating conditions, etc. At the same time, the phase and physical properties of the refractory material from room temperature to working temperature should also be considered. Change process and change mechanism, and application conditions of refractory materials, etc.

Selection and application of Refractory lining material for induction furnace

(1) When smelting cast iron and non-ferrous metals in a coreless induction furnace, SiO2, ZrO2•SiO2 and their composite refractories are generally selected. Because ZrO2•SiO2 is thermally decomposed at high temperature to generate £ZrO2 and fSiO2, which are evenly distributed in the material, thus giving the material high temperature plasticity and corrosion resistance, indicating that ZrO2 can prolong the service life of SiO2 refractory materials.

(2) The coreless induction furnace can use either the acid steelmaking method or the alkaline steelmaking method. Acid steelmaking refractories are the ...
... same as smelting cast iron, and acid refractories are used; basic steelmaking uses neutral or alkaline refractories.

(3) When making steel in a small coreless induction furnace, magnesia refractory materials are usually used for lining, but this refractory material has poor thermal shock resistance, and is easily penetrated by slag, resulting in structural peeling and premature damage, so it is difficult to Adapt to the use environment of large capacity and intermittent operation.

(4) Refractory materials made of MgO-Al2O3 or MgO-Spinal mixtures are used in steelmaking of medium-sized coreless induction furnaces in normal operation, all of which belong to MgO-spind series refractories.

(5) The medium-sized coreless induction furnace that uses a variety of scrap steels as raw materials for steelmaking uses Al2O3-MgO (about 10% MgO) refractory materials to obtain high service life.

(6) Medium-sized induction furnaces with direct reduced iron balls as additives should use MgO-Al2O3-Cr2O3 (chromium ore added) refractories. Due to the reaction of MgO, Al2O3, Cr2O3, etc. to form composite spinel when heated at high temperature, it has high refractory performance and strong corrosion resistance. long.

(7) Large-scale coreless induction furnaces use spinel refractories made of pre-synthesized Spinel pellets, and can also use MgO (coarse particles, fine powder), Spinel (medium particles. Fine powder) and Al2O3 particles. Mixtures, and MgO-Spine based refractories made by carefully balancing the ratio of pre-synthesized Spinel and in-situ Spinel. Both types of refractories are compatible with the operating conditions of large coreless induction furnaces.

(8)The operating temperature of the cored induction furnace for smelting gray iron and cast iron is 1450~1550℃, which is not very high. Although the temperature at the melting ditch and the water jacket of the inductor is as high as 1600~1700°C, the selection of refractory materials is not very difficult due to the implementation of water cooling.