Casting method of electric furnace water cooling cast steel furnace cover

Abstract

The invention relates to a casting method of electric furnace water cooling cast steel furnace cover, which adopts a cast steel material to cast a base body and a cooling water pipe. The casting method comprises the following steps: adding a slagging agent and a silicon iron alloy block in molten steel for casting steel; putting the cooling water pipe into a casting model and leading a liquid cold medium and a composite solid cooling medium to pass through the cooling water pipe; using molten steel for casting steel to cast the base body, casting the middle part of the cooling water pipe into the base body and leading the two ends thereof to extend from the base body; leading the casting model to be horizontal when in modeling, leading a feeder head to be modeled lopsidedly toward one side and heightening one side of the feeder head of the model after the model is boxed; adopting an upper layer of inner sprue and a lower layer of lower sprue to carry out stepped casting so as to form sequential solidification; and cooling and disassembling the model. The casting method can effectively avoid the cooling water pipe from being penetrated in a fusing manner during the casting process, avoids air gaps from being generated between the base body and the cooling water pipe, avoids refusion and recrystallization, accurately realizes the microfusion of the outer surface of the cooling water pipe, prolongs the service life of the electric furnace water cooling cast steel furnace cover, further prolongs the service life of a metallurgical high-temperature kiln, saves production cost and improves the mechanical performance of the electric furnace water cooling cast steel furnace cover.

Description

technical field [0001] The invention relates to a high-temperature metallurgical furnace, in particular to a casting method for a water-cooled cast steel cover of an electric furnace used in a high-temperature metallurgical furnace, and belongs to the technical field of steelmaking and metallurgy. Background technique [0002] The electric furnace water-cooled furnace cover is a cooling device for the metallurgical high-temperature furnace, which can protect the metallurgical high-temperature furnace from the erosion of the high-temperature fluid in the furnace body and mechanical wear, prolong the life of the metallurgical high-temperature furnace, and ensure its safe and stable production. Once there is a problem with the cooling equipment, the metallurgical high-temperature furnace must be completely shut down for maintenance, which will cause major economic losses. Therefore, the life and performance of the water-cooled furnace cover of the electric furnace determine the...

AI Technical Summary

Problems solved by technology

Taking the water-cooled furnace cover of the most widely used ductile iron electric furnace as an example, it has the following disadvantages: (1) The water-cooled furnace cover of the ductile iron electric furnace must be equipped with an anti-carburization coating outside the cooling channel to form an air gap between the channel and the substrate. The air gap significantly increases the heat transfer resistance of the water-cooled furnace cover of the electric furnace, deteriorates the heat transfer effect of the water-cooled furnace cover of the electric furnace, increases the temperature of the working surface of the water-cooled furnace cover of the electric furnace, and accelerates the damage of the water-cooled furnace cover of the electric furnace; (2) the ductile iron substrate is covered with Spherical graphite of different sizes (particle size 0.025 ~ 0.150mm), spherical graphite is equivalent to the formation of countless tiny holes after being oxidized, forming the birthplace of cracks and cracks, accelerating the expansion of cracks and cracks, resulting in electric furnace The service life of the water-cooled furnace cover is shortened, which increases resource consumption, which is not conducive to the longevity and energy saving of the water-cooled furnace cover of the electric furnace; (3) when casting large-scale ductile graphite castings, C, S, and P are easily pushed to the liquid state during the columnar crystallization process. The central equiaxed crystal region forms a segregation-enriched region, which causes a large difference in elongation between the surface and the center of the casting, and the surface elongation is more than twice that of the center, which promotes the generation and expansion of cracks or cracks in ductile iron, which is not conducive to The water-cooled furnace cover of the electric furnace has a long life; (4) The linear expansion coefficient of ductile iron changes steadily below 600°C, but above 600°C, it will experience rapid irreversible "growth" with the increase of temperature. When the temperature is greater than 709°C, the matrix The structure undergoes a phase transformation, the expansion coefficient and internal stress increase sharply, and the damage speed is accelerated; (5) The thermal conductivity and thermal shock resistance of ductile iron are poor, and its thermal conductivity is only 30w m -2 ·K -1 , which is not conducive to the efficient cooling of the water-cooled furnace cover of the electric furnace

Simply considering it from a certain angle cannot solve the problem very well, and it needs to conduct systematic research on the basic principles of interdisciplinary and multidisciplinary

Due to the above limitations, the current application of cast steel on the water-cooled cover of the electric furnace still cannot meet the requirements of industrial applications

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