Analysis of the causes of coreless induction furnace penetration and lining peeling
The coreless induction furnace manufacturer tells you that in general, high-quality refractory materials have a good effect on the furnace and have a long life, but the use conditions cannot be ignored. Just like a refractory material used on the same thermal equipment, due to changes in the use conditions, The results are often very different. There are many reasons for the failure of the furnace lining, such as furnace wear and peeling of the furnace lining. The following mainly introduces the analysis of the cause of the coreless induction furnace and the lining peeling off.
The phenomenon of furnace penetration is as follows: a large amount of metal penetrates into the cracks of the refractory material.
Wearing the furnace will cause: Coreless induction furnace manufacturer tells you that the metal permeates around the furnace; the life of the furnace lining is significantly reduced; the early grounding alarm; the potential risk of molten metal drilling into the coil; the overall sintering of the dry vibrating material without loose layers ; Furnace lining is shown as continuous expansion from the furnace mouth; the oxidation of the part through the furnace will cause local refractory corrosion and so on.
The coreless induction furnace manufacturer tells you that the main reason for the formation of the furnace is the cracks formed by the cooling and heating cycles, including horizontal cracks, vertical cracks and cracks in any direction. The main reasons for the formation of horizontal cracks are:
①Lamination: The manufacturer of Coreless induction furnace tells you the incorrect method of building the furnace, causing the furnace lining to not form a dense knotted layer of furnace lining;
② Furnace lining attachment: It often appears at the junction of the liquid outlet and the working furnace lining, which can be solved by changing the construction method of the furnace nozzle. Vertical cracks are caused by thermal shock, mainly caused by incorrect cooling process and remelting process. Cracks in any direction are generally caused by mechanical collision or demoulding.
Flaking off the lining:
Flaking of the furnace lining is a phenomenon in which the refractory material falls off the sintered furnace wall in lumps or flakes.
The causes of lining spalling are:
(1) The manufacturer of Coreless induction furnace tells you that improper furnace building or sintering has caused the furnace lining to not form a good sintered layer and cause the furnace lining to peel off.
(2) Water vapor: When the furnace lining is sintered, the speed is too fast, and the water in the refractory material is too late to be discharged. At high temperature, H2O decomposes into H2 and O2. According to the ideal gas equation: PV=nRT, it can be seen that the temperature of the gas rises rapidly, the product of pressure and volume of the gas will rapidly expand, the volume expands rapidly, and the gas with a rapid increase in pressure will lead to unsintered A good lining is peeling off.
(3) Mechanical spalling: The repeated impact of the feed on the furnace lining, especially the furnace bottom, is the main cause of mechanical spalling.
(4) Expansion and peeling: The coreless induction furnace manufacturer tells you that after the molten metal corrodes the furnace lining, the thermal expansion rate of the part eroded by the metal is inconsistent with the thermal expansion rate of the non-eroded part, which makes it easy to produce irregular stress at the interface between the two. The lining falls off.
(5) Extrusion spalling: often occurs at the bottom of the furnace, caused by the impact of the feed on the bottom of the furnace and the long-term pressure of the molten metal on the bottom of the furnace.
(6) Hot spalling: The coreless induction furnace manufacturer tells you that the temperature changes rapidly, and the fluctuation is too fast in a short period of time, which will cause the internal stress of the refractory material to be large, cracking, peeling and damage.