阅读说明：本技术 一种熔铸高纯氧化铝耐火制品的保温成型的方法及保温箱及得到的耐火制品 (Heat insulation molding method and heat insulation box of fusion-cast high-purity alumina refractory product and refractory product obtained by heat insulation molding method ) 是由 张红哲 谢永刚 李龙刚 张艺锋 于 2021-06-23 设计创作，主要内容包括：本发明提供一种熔铸高纯氧化铝耐火制品的保温成型的方法及保温箱及得到的耐火制品,一种熔铸高纯氧化铝耐火制品的保温成型的方法,在模型的外部设有保温层,模型底部设有的保温层为保温层Ⅰ,模型上部设有的保温层为保温层Ⅲ,保温层Ⅲ的厚度大于保温层Ⅰ的厚度,模型四周设有的保温层为保温层Ⅱ,从下到上,保温层Ⅱ的上部厚度大于保温层Ⅱ的下部厚度；先对模型内部进行通风,排除模型内的水和水汽,然后从模型的浇口浇入熔融液,自然冷却保温；按重量百分比计,熔融液中氧化铝含量为90%以上,氧化钠含量为0.5%-8%、氧化硅+氧化钙+氧化铁+氧化钛含量之和≤2%。减少或者避免产品表面气孔的产生,减少温度梯度产品内部形成的缩孔和裂纹。(The invention provides a heat preservation forming method of a fusion cast high-purity alumina refractory product, a heat preservation box and an obtained refractory product, wherein the heat preservation forming method of the fusion cast high-purity alumina refractory product is characterized in that a heat preservation layer is arranged outside a model, the heat preservation layer arranged at the bottom of the model is a heat preservation layer I, the heat preservation layer arranged at the upper part of the model is a heat preservation layer III, the thickness of the heat preservation layer III is larger than that of the heat preservation layer I, the heat preservation layer arranged at the periphery of the model is a heat preservation layer II, and the thickness of the upper part of the heat preservation layer II is larger than that of the lower part of the heat preservation layer II from bottom to top; ventilating the interior of the model, removing water and water vapor in the model, pouring molten liquid from a pouring gate of the model, and naturally cooling and preserving heat; the content of alumina in the melting liquid is more than 90 percent, the content of sodium oxide is 0.5 to 8 percent, and the sum of the contents of silicon oxide, calcium oxide, ferric oxide and titanium oxide is less than or equal to 2 percent. The generation of pores on the surface of the product is reduced or avoided, and shrinkage cavities and cracks formed in the temperature gradient product are reduced.)

1. A heat preservation forming method of a fusion-cast high-purity alumina refractory product is characterized by comprising the following steps: the heat preservation layer is arranged outside the model, the heat preservation layer arranged at the bottom of the model is a heat preservation layer I, the heat preservation layer arranged at the upper part of the model is a heat preservation layer III, the thickness of the heat preservation layer III is larger than that of the heat preservation layer I, the heat preservation layer arranged at the periphery of the model is a heat preservation layer II, and from bottom to top, the thickness of the upper part of the heat preservation layer II is larger than that of the lower part of the heat preservation layer II; ventilating the interior of the model, removing water and water vapor in the model, pouring molten liquid from a pouring gate of the model, and naturally cooling and preserving heat; the content of alumina in the melting liquid is more than 90 percent, the content of sodium oxide is 0.5 to 8 percent, and the sum of the contents of silicon oxide, calcium oxide, ferric oxide and titanium oxide is less than or equal to 2 percent.

2. The method for the warm forming of a fused-cast high-purity alumina refractory product according to claim 1, characterized in that: and the heat preservation layer II is in an inverted isosceles trapezoid shape when viewed from the side.

3. The method for the warm forming of a fused-cast high-purity alumina refractory product according to claim 1, characterized in that: ventilating the interior of the model, wherein the ventilation temperature is more than or equal to 100 ℃, and preferably 100-150 ℃.

4. The method for the warm forming of a fused-cast high-purity alumina refractory product according to claim 1, characterized in that: before the molten liquid is poured into the model, a fused alumina block is placed in the middle of the lower portion of the bottom of the model to serve as a bottom supporting block, a fused alumina block is arranged above the fused alumina bottom supporting block to serve as a center block, and the center block is located in the middle of the interior of the model.

5. The method for the warm forming of the fused-cast high-purity alumina refractory product according to claim 4, characterized in that: the central block has the same shape as the interior of the model.

6. The method for the shaping at elevated temperature of a fused-cast high-purity alumina refractory product according to claim 4 or 5, characterized in that: when at least two center blocks are uniformly arranged in the middle of the model, side supporting blocks are uniformly arranged around the side part of each center block, the outer wall of the side part of each center block is close to the outer wall of the side part in the model, one end of each side supporting block is tightly attached to the inner wall of the model, and the other end of each side supporting block is tightly attached to the outer wall of the side part of each center block; and one end of the side supporting block is tightly attached to the side outer wall of one central block of the model, and the other end of the side supporting block is tightly attached to the side outer wall of the other central block.

7. The method for the shaping at elevated temperature of a fused-cast high-purity alumina refractory product according to claim 4 or 5, characterized in that: the middle part of the model is only provided with a center block, the periphery of the side part of the center block is uniformly provided with side supporting blocks, one section of each side supporting block is tightly attached to the inner wall of the model, and one end of each side supporting block is tightly attached to the outer wall of the side part of the center block.

8. The utility model provides a set up at outside insulation can of model heat preservation which characterized in that: the incubator is adapted to the exterior of the incubator of claim 1.

9. The insulation can of claim 8 disposed outside the insulation layer of the mold, wherein: the insulation can is provided with an upper cover which is rotatably connected with the insulation can, the side part of the insulation can is higher than the model, and a space for arranging an insulation layer III is formed between the upper cover and the upper end of the model and between the upper cover and the part of the side part of the insulation can which is higher than the model.

10. The fused and cast high purity alumina refractory product obtained by the method for the shaping at elevated temperature of the fused and cast high purity alumina refractory product according to any one of claims 1 to 7.

Technical Field

The application relates to a fusion-cast high-purity alumina refractory product, in particular to a heat-preservation forming method and a heat-preservation box of the fusion-cast high-purity alumina refractory product and the obtained refractory product.

Background

In the preparation of the fusion-cast high-purity alumina refractory product, pores are easily formed on the surface of the fusion-cast high-purity alumina refractory product, and shrinkage cavities and cracks are easily formed inside the fusion-cast high-purity alumina refractory product, so that the overall quality of the fusion-cast high-purity alumina refractory product is influenced. The reason for analyzing the formation of pores on the surface is that pores are formed in the process that the surface of the fused and cast high-purity alumina refractory product absorbs moisture in the molding process of the fused and cast high-purity alumina refractory product in the model; in addition, shrinkage is not uniform due to non-uniform temperature, so that shrinkage cavities and cracks are easily formed in the fused and cast high-purity alumina refractory product.

Disclosure of Invention

In order to solve the problems, the invention provides a heat preservation forming method of a fusion-cast high-purity alumina refractory product, a heat preservation box and the obtained refractory product, which can reduce or avoid the generation of pores on the surface of the product and reduce shrinkage cavities and cracks formed in the temperature gradient product.

The object of the invention is achieved in the following way: a heat preservation forming method of a fusion cast high-purity alumina refractory product is characterized in that a heat preservation layer is arranged outside a model, the heat preservation layer arranged at the bottom of the model is a heat preservation layer I, the heat preservation layer arranged at the upper part of the model is a heat preservation layer III, the thickness of the heat preservation layer III is larger than that of the heat preservation layer I, the heat preservation layer arranged at the periphery of the model is a heat preservation layer II, and the thickness of the upper part of the heat preservation layer II is larger than that of the lower part of the heat preservation layer II from bottom to top; ventilating the interior of the model, removing water and water vapor in the model, pouring molten liquid from a pouring gate of the model, and naturally cooling and preserving heat; the content of alumina in the melting liquid is more than 90 percent, the content of sodium oxide is 0.5 to 8 percent, and the sum of the contents of silicon oxide, calcium oxide, ferric oxide and titanium oxide is less than or equal to 2 percent.

And the heat preservation layer II is in an inverted isosceles trapezoid shape when viewed from the side.

Ventilating the interior of the model, wherein the ventilation temperature is more than or equal to 100 ℃, and preferably 100-150 ℃.

Before the molten liquid is poured into the model, a fused alumina block is placed in the middle of the lower portion of the bottom of the model to serve as a bottom supporting block, a central block is arranged above the fused alumina bottom supporting block and serves as a central block, and the central block is located in the middle of the interior of the model.

The central block has the same shape as the interior of the model.

When at least two center blocks are uniformly arranged in the middle of the model, side supporting blocks are uniformly arranged around the side part of each center block, the outer wall of the side part of each center block is close to the outer wall of the side part in the model, one end of each side supporting block is tightly attached to the inner wall of the model, and the other end of each side supporting block is tightly attached to the outer wall of the side part of each center block; and one end of the side supporting block is tightly attached to the side outer wall of one central block of the model, and the other end of the side supporting block is tightly attached to the side outer wall of the other central block.

The middle part of the model is only provided with a center block, the periphery of the side part of the center block is uniformly provided with side supporting blocks, one section of each side supporting block is tightly attached to the inner wall of the model, and one end of each side supporting block is tightly attached to the outer wall of the side part of the center block.

An insulation can arranged outside a model insulation layer is adapted to the insulation layer.

The insulation can is provided with an upper cover which is rotatably connected with the insulation can, the side part of the insulation can is higher than the model, and a space for arranging an insulation layer III is formed between the upper cover and the upper end of the model and between the upper cover and the part of the side part of the insulation can which is higher than the model.

The fused and cast high-purity alumina refractory product is obtained according to the heat-preservation forming method of the fused and cast high-purity alumina refractory product.

Compared with the prior art, the invention provides a heat-insulating molding method of a fusion-cast high-purity alumina refractory product, which comprises the steps of ventilating the interior of a model, and removing water and water vapor in the model, so that the surface of molten liquid cannot absorb water, and pores on the surface of a product are avoided; according to the arrangement of the heat-insulating layer, in the process of shrinkage molding of the molten liquid in the model, the temperature of each layer in height is as consistent as possible, and in the process of gradual solidification of the temperature from bottom to top, the shrinkage can be fully supplemented, so that the temperature of each layer is prevented from being uneven, and shrinkage cavities and cracks formed by temperature gradients are reduced; in addition, the phenomenon that shrinkage cavities and cracks are easily caused due to slowest cooling and latest shrinkage of the central part is avoided, and therefore the cast alumina block is placed in the middle of the model.

Drawings

FIG. 1 is a schematic structural view of an insulation layer according to embodiment 1.

Fig. 2 is a schematic structural diagram of the insulating layer and the central block, the bottom supporting block and the side supporting block in the insulating process in embodiments 2 to 4.

Detailed Description

The production process flow of the fusion casting high-purity alumina refractory product comprises the steps of designing, modeling, burdening, melting, forming, casting, preserving heat, taking out and processing.

(1) Designing: designing a model of a fusion-cast high-purity alumina refractory product. The model is a grinding tool and is used for holding molten liquid formed by high-purity alumina fused refractory product raw materials and solidifying the molten liquid into blocks.

(2) Model: and (3) manufacturing a casting high-purity alumina refractory product model.

(3) Preparing materials: weighing the required raw materials such as high-temperature calcined alumina, silicon oxide, sodium oxide and the like according to the weight part ratio requirement, accurately weighing, and uniformly stirring;

the raw material sources can be as follows:

the production area of the high-temperature calcined alumina: japanese Zhao He electrician

Production area of silicon oxide: hainan province

③ alkali powder: hubei bicyclic, a feedstock that provides sodium oxide.

(4) Melting: fully stirring and mixing the raw materials, putting the mixture into a three-phase electric furnace, heating the mixture to 2100-2200 ℃, and melting the mixture;

(5) and (3) grouping: and putting the manufactured casting high-purity alumina refractory product model into a heat preservation box, and filling heat preservation materials around the casting high-purity alumina refractory product model to form the heat preservation layers I and II, wherein the heat preservation materials can be heat preservation alumina or other heat preservation materials.

(6) Casting: and casting the molten feed liquid into a combined casting high-purity alumina refractory product model, and covering a heat-insulating material on the upper part of the casting high-purity alumina refractory product model to form the heat-insulating layer III, wherein the heat-insulating material can be heat-insulating alumina or other heat-insulating materials.

(7) And (3) heat preservation: the heat preservation boxes are placed in a centralized manner and cooled naturally;

(8) taking out: after keeping the temperature for a certain number of days, taking the cast fusion-cast high-purity alumina refractory product out of the heat preservation box to obtain a semi-finished product, and preparing for subsequent processing;

(9) processing: and (3) carrying out cold processing treatment such as cutting, grinding, drilling and the like on the fused and cast high-purity alumina semi-finished product cooled to room temperature to finally obtain the fused and cast high-purity alumina finished product.

The application mainly provides a heat-preservation forming method of a fusion-cast high-purity alumina refractory product, namely a casting step and a heat-preservation step in the process flow. The other steps are the same as the process flow steps described above.

As shown in figure 2, a heat preservation shaping method of founding high-purity alumina refractory product is equipped with the heat preservation in the outside of model 1, and the heat preservation that the model bottom was equipped with is heat preservation I3, and the heat preservation that the model upper portion was equipped with is heat preservation III 4, and the thickness of heat preservation III 4 is greater than the thickness of heat preservation I3, and the thickness direction of heat preservation III 4 here, the thickness direction of heat preservation I3 are from the top down direction or from the bottom up direction. The heat preservation that the model was equipped with all around or the lateral part is heat preservation II 5, to heat preservation II 5: from bottom to top, the thickness of the upper part of the heat preservation layer II 5 is larger than that of the lower part of the heat preservation layer II 5, the thickness of the heat preservation layer II is the distance from the side part of the model, the close contact position of the heat preservation layer II and the outer wall of the model to the close contact position of the heat preservation layer II and the inner wall of the heat preservation box; ventilating the interior of a model 1, removing water and water vapor in the model, pouring molten liquid from a pouring gate 2 of the model 1, and naturally cooling and preserving heat; the content of alumina in the melting liquid is more than 90 percent, the content of sodium oxide is 0.5 to 8 percent, and the sum of the contents of silicon oxide, calcium oxide, ferric oxide and titanium oxide is less than or equal to 2 percent.

Ventilating the interior of the model 1, and removing water and water vapor in the model to ensure that the surface of the molten liquid cannot absorb water, thereby generating pores on the surface of the product; according to the arrangement of the heat-insulating layer, in the process of shrinkage molding of the molten liquid in the model, the temperature of each layer in height is as consistent as possible, and in the process of gradual solidification of the temperature from bottom to top, the shrinkage can be fully supplemented, so that the temperature of each layer is prevented from being uneven, and shrinkage cavities and cracks formed by temperature gradients are reduced;

viewed from the side, the heat preservation layer II 5 is in an inverted isosceles trapezoid shape.

For convenience and attractiveness, the heat-insulating layer I3 is arranged at the bottom of the model, the periphery of the side part is connected with the heat-insulating layer II 5, the periphery of the bottommost part is on the same curved surface or plane, and the periphery of the side part of the heat-insulating layer III 4 arranged at the upper part of the model and the periphery of the uppermost part of the heat-insulating layer II 5 are on the same curved surface or plane.

Ventilating the interior of the model, wherein the ventilation temperature is more than or equal to 100 ℃, and preferably 100-150 ℃.

Before the molten liquid is poured into the model, a fused alumina block is placed in the middle of the lower portion of the bottom of the model 1 to serve as a bottom supporting block 8, a central block 9 which serves as a fused alumina block is arranged above the fused alumina bottom supporting block 8, and the central block 9 is located in the middle of the interior of the model. And the phenomenon that the central part is cooled slowest and contracts latest to cause shrinkage cavities and cracks most easily is avoided, so that the cast alumina block is placed in the middle of the model. Because the model is provided with the upper die and the lower die, the upper die can be taken away, and the center block, the bottom supporting block and the like are arranged in the lower die.

The central block 9 is the same shape as the interior of the mould.

When the middle part of the model is uniformly provided with at least two central blocks 9, the periphery of the side part of each central block is uniformly provided with a side supporting block 10, the outer wall of the side part of each central block is close to the outer wall of the side part in the model, one end of each side supporting block is tightly attached to the inner wall of the model, and the other end of each side supporting block is tightly attached to the outer wall of the side part of each central block; and one end of the side supporting block is tightly attached to the side outer wall of one central block of the model, and the other end of the side supporting block is tightly attached to the side outer wall of the other central block.

The middle part of the model is only provided with a central block 9, the periphery of the side part of the central block is evenly provided with side supporting blocks 10, one end of each side supporting block 10 is tightly attached to the inner wall of the model 1, and the other end of each side supporting block 10 is tightly attached to the outer wall of the side part of the central block 9.

An insulation can arranged outside a model insulation layer is adapted to the insulation layer. The heat preservation box which is matched with the heat preservation layer is arranged outside the heat preservation layer, the model is arranged in the heat preservation box, and the heat preservation layer with the shape is filled in the model and the heat preservation box. The heat preservation box is a device for bearing and fixing the external structure of the heat preservation layer, and the heat preservation layer can be conveniently fixed when the heat preservation layer is powder or liquid.

For convenience, the insulation can is provided with an upper cover 7, the upper cover 7 is rotatably connected with the side part 6 of the insulation can, the side part 6 of the insulation can is higher than the model, and a space for arranging an insulation layer III 4 is formed between the upper cover 7 and the upper end of the model 1 and between the upper cover and the part of the side part of the insulation can, which is higher than the model. Namely, a certain distance is left between the upper cover and the model, and the side part of the heat preservation box is higher than the model, so that the heat preservation layer III can be conveniently arranged.

The fused and cast high-purity alumina refractory product is obtained according to the heat-preservation forming method of the fused and cast high-purity alumina refractory product.

The present invention is described in detail below with reference to specific embodiments, it should be noted that the embodiments are only used for further illustration of the present invention, and should not be construed as limiting the scope of the present invention, and those skilled in the art can make modifications and adaptations of the present invention based on the above-mentioned disclosure.

According to different compositions, the alumina molten liquid obtained by the treatment according to the process flow is divided into three batches: the first batch comprises, by weight, 94% of alumina, 4% of sodium oxide and less than or equal to 2% of the sum of the contents of silicon oxide, calcium oxide, iron oxide and titanium oxide; the second batch comprises, by weight, 92% of alumina, 6.5% of sodium oxide and less than or equal to 1.5% of the sum of silicon oxide, calcium oxide, iron oxide and titanium oxide; in the third batch, the content of alumina in the molten liquid is 98 percent, the content of sodium oxide is 1 percent, and the sum of the contents of silicon oxide, calcium oxide, iron oxide and titanium oxide is less than or equal to 1 percent. The same batch of alumina melts were separately molded by holding the temperature according to the following examples.

Example 1

As shown in fig. 1, a heat insulation layer is arranged outside a model 1, the heat insulation layer arranged at the bottom of the model 1 is a heat insulation layer i 3, the heat insulation layer arranged at the upper part of the model is a heat insulation layer iii 4, the thickness of the heat insulation layer iii 4 is larger than that of the heat insulation layer i 3, the heat insulation layer arranged around the model is a heat insulation layer ii 5, from bottom to top, the thickness of the heat insulation layer ii is the same, the heat insulation layer arranged at the bottom of the model is that the periphery of the side part of the heat insulation layer i and the periphery of the bottommost part of the heat insulation layer ii are on the same curved surface or plane, and the heat insulation layer arranged at the upper part of the model is that the periphery of the side part of the heat insulation layer iii and the periphery of the uppermost part of the heat insulation layer ii are on the same curved surface or plane; because the heat preservation box which is matched with the heat preservation layer is arranged outside the heat preservation layer, the model is arranged in the heat preservation box, and the heat preservation layer with the shape is filled in the model and the heat preservation box. For convenience, the insulation can is provided with an upper cover 7, the upper cover 7 is rotatably connected with the insulation can side part 6, a certain distance is reserved between the upper cover and the model, and the insulation can side part 6 is higher than the model 1, so that the insulation can side part can be conveniently provided with an insulation layer III 4.

Therefore, the heat-preservation forming method of the fusion-cast high-purity alumina refractory product comprises the following steps: (1) arranging a heat preservation layer I3 at the bottom of the heat preservation box, then placing the model in the center of the upper part of the heat preservation layer I3 of the heat preservation box, then filling a heat preservation layer II 5 in the center of the outer part of the model in the heat preservation box, and finally, from bottom to top, ensuring that the thickness of the heat preservation layer II is the same; (2) and then pouring the molten liquid from a pouring gate 2 of the model, covering the upper end of the pouring gate of the model after the molten liquid is poured, covering the upper part of the model with a heat-insulating layer III 4, covering an upper cover 7 of the heat-insulating box, and then naturally cooling and insulating.

Example 2

As shown in fig. 2, be equipped with the heat preservation in the outside of model 1, the heat preservation that the model bottom was equipped with is heat preservation I3, and the heat preservation that model upper portion was equipped with is heat preservation III 4, and the thickness of heat preservation III 4 is greater than the thickness of heat preservation I3, and the heat preservation that the model was equipped with all around is heat preservation II 5, to heat preservation II 5: from bottom to top, the upper thickness of the temperature layer II 5 is larger than the lower thickness of the heat preservation layer II 5, the heat preservation layer II 5 is in an inverted isosceles trapezoid shape when viewed from the side, the periphery of the side part of the heat preservation layer I and the periphery of the bottommost part of the heat preservation layer II are on the same curved surface or plane, and the periphery of the side part of the heat preservation layer III and the periphery of the uppermost part of the heat preservation layer II are on the same curved surface or plane; because the heat preservation box which is matched with the heat preservation layer is arranged outside the heat preservation layer, the model is arranged in the heat preservation box, and the heat preservation layer with the shape is filled in the model and the heat preservation box. For convenience, the heat preservation box is provided with an upper cover 7 which is rotatably connected with the heat preservation box side part 6, a certain distance is reserved between the upper cover 7 and the model 1, and the heat preservation box side part 6 is higher than the model 1, so that the heat preservation layer III 4 can be conveniently arranged.

Therefore, the heat-preservation forming method of the fusion-cast high-purity alumina refractory product comprises the following steps: (1) arranging a heat preservation layer I3 at the bottom of the heat preservation box, then placing the model in the center of the upper part of the heat preservation layer I3 of the heat preservation box, then filling a heat preservation layer II 5 in the center of the outer part of the model in the heat preservation box, and finally, viewing from the side, the heat preservation layer II 5 is in an inverted isosceles trapezoid shape; (2) ventilating the interior of the model at the ventilation temperature of 100 ℃ and 150 ℃, and removing water and water vapor in the model; (3) and then pouring molten liquid from a pouring gate 2 of the model, covering the upper end of the pouring gate of the model after the molten liquid is poured, covering the upper part of the model with a heat-insulating layer III 4, covering the upper cover of the heat-insulating box, and then naturally cooling and insulating.

Example 3

Be equipped with the heat preservation in the outside of model 1, the heat preservation that the model bottom was equipped with is heat preservation I3, and the heat preservation that model upper portion was equipped with is heat preservation III 4, and the thickness of heat preservation III 4 is greater than the thickness of heat preservation I3, and the heat preservation that the model was equipped with all around is heat preservation II 5, to heat preservation II 5: from bottom to top, the upper thickness of the heat preservation layer II 5 is larger than the lower thickness of the heat preservation layer II 5, the heat preservation layer II is in an inverted isosceles trapezoid shape when viewed from the side, the periphery of the side part of the heat preservation layer I and the periphery of the bottommost part of the heat preservation layer II are on the same curved surface or plane, and the periphery of the side part of the heat preservation layer III and the periphery of the uppermost part of the heat preservation layer II are on the same curved surface or plane; because the heat preservation box which is matched with the heat preservation layer is arranged outside the heat preservation layer, the model is arranged in the heat preservation box, and the heat preservation layer with the shape is filled in the model and the heat preservation box. For convenience, the insulation can is provided with an upper cover 7, the upper cover 7 is rotatably connected with the side part of the insulation can, a certain distance is reserved between the upper cover and the model, and the side part 6 of the insulation can is higher than the model, so that the insulation can be conveniently provided with an insulation layer III.

Therefore, the heat-preservation forming method of the fusion-cast high-purity alumina refractory product comprises the following steps: (1) arranging a heat preservation layer I3 at the bottom of the heat preservation box, and then placing the model 1 in the center of the upper part of the heat preservation layer I3 of the heat preservation box; (2) the upper die 11 of the model 1 is taken away, and a central block, a bottom supporting block and the like are arranged in the lower die 12 of the model, and the method specifically comprises the following steps: firstly, a fused cast alumina block is placed in the middle of the bottom of a lower die 12 of a model to serve as a bottom supporting block 8, a fused cast alumina block with the same shape as the interior of the model is arranged above the fused cast alumina bottom supporting block to serve as a central block 9, the central block is positioned in the middle of the interior of the model, side supporting blocks 10 are uniformly arranged on the periphery of the side part of the central block, one section of each side supporting block is tightly attached to the inner wall of the model 1, and one end of each side supporting block is tightly attached to the outer wall of the side part of the central block 9; (3) placing an upper die 11 above a lower die 12, closing the dies, filling a heat-insulating layer II in the heat-insulating box at the center of the outer part of the die, and finally, viewing from the side, wherein the heat-insulating layer II is in an inverted isosceles trapezoid shape; (4) ventilating the interior of the model at the ventilation temperature of 100 ℃ and 150 ℃, and removing water and water vapor in the model; (5) and then pouring molten liquid from a pouring gate 2 of the model, covering the upper end of the pouring gate 2 of the model after the molten liquid is poured, covering the upper part of the model with a heat insulation layer III, covering the upper cover of the heat insulation box, and then naturally cooling and insulating.

Or the heat-preservation forming method of the fusion-cast high-purity alumina refractory product comprises the following steps:

(1) the upper die 11 of the model 1 is taken away, and a central block, a bottom supporting block and the like are arranged in the lower die 12 of the model, and the method specifically comprises the following steps: firstly, a fused cast alumina block is placed in the middle of the lower part of the bottom of a lower die 12 of a model to be used as a bottom supporting block 8, a fused cast alumina block with the same shape as the interior of the model is arranged above the fused cast alumina bottom supporting block to be used as a central block 9, the central block 9 is positioned in the middle of the interior of the model, side supporting blocks 10 are uniformly arranged on the periphery of the side part of the central block, one section of each side supporting block is tightly attached to the inner wall of the model, and the other end of each side supporting block is tightly attached to the outer wall of the side part of the central block; (2) placing the upper die above the lower die, and closing the dies; (3) arranging a heat preservation layer I3 at the bottom of the heat preservation box, then placing the model in the center of the upper part of the heat preservation layer I3 of the heat preservation box, then filling a heat preservation layer II 5 in the center of the outer part of the model in the heat preservation box, and finally, viewing from the side, the heat preservation layer II is in an inverted isosceles trapezoid shape; (4) ventilating the interior of the model at the ventilation temperature of 100 ℃ and 150 ℃, and removing water and water vapor in the model; (5) and then pouring molten liquid from a pouring gate 2 of the model, covering the upper end of the pouring gate 2 of the model after the molten liquid is poured, covering the upper part of the model with a heat-insulating layer III 4, covering an upper cover 7 of the heat-insulating box, and then naturally cooling and insulating.

Example 4

As shown in fig. 2, be equipped with the heat preservation in the outside of model, the heat preservation that the model bottom was equipped with is heat preservation I, and the heat preservation that model upper portion was equipped with is heat preservation III, and the thickness of heat preservation III 4 is greater than the thickness of heat preservation I3, and the heat preservation that the model was equipped with all around is heat preservation II, to heat preservation II 5: from bottom to top, the upper thickness of the heat preservation layer II 5 is larger than the lower thickness of the heat preservation layer II 5, the heat preservation layer II is in an inverted isosceles trapezoid shape when viewed from the side, the periphery of the side part of the heat preservation layer I and the periphery of the bottommost part of the heat preservation layer II are on the same curved surface or plane, and the periphery of the side part of the heat preservation layer III and the periphery of the uppermost part of the heat preservation layer II are on the same curved surface or plane; because the heat preservation box which is matched with the heat preservation layer is arranged outside the heat preservation layer, the model is arranged in the heat preservation box, and the heat preservation layer with the shape is filled in the model and the heat preservation box. In order to facilitate the operation, the heat preservation box is provided with an upper cover which is rotatably connected with the heat preservation box, a certain distance is reserved between the upper cover and the model, and the side part of the heat preservation box is higher than the model, so that the heat preservation layer III can be conveniently arranged.

Three center blocks are uniformly arranged in the middle of the model, a side supporting block 10 is uniformly arranged on the periphery of the side part of each center block 9, the outer wall of the side part of each center block 9 is close to the outer wall of the side part in the model, one end of each side supporting block is tightly attached to the inner wall of the model, and the other end of each side supporting block is tightly attached to the outer wall of the side part of each center block; and one end of the side supporting block is tightly attached to the side outer wall of one central block of the model, and the other end of the side supporting block is tightly attached to the side outer wall of the other central block.

Therefore, the heat-preservation forming method of the fusion-cast high-purity alumina refractory product comprises the following steps: (1) arranging a heat preservation layer I at the bottom of the heat preservation box, and then placing the model in the center of the upper part of the heat preservation layer I of the heat preservation box; (2) the upper die of the model is taken away, and the center block, the bottom supporting block and the like are arranged in the lower die of the model, and the method specifically comprises the following steps: the method comprises the following steps of firstly, placing a fused cast alumina block as a bottom supporting block for supporting a center block in the middle of the bottom of a lower die of a model, then placing a fused cast alumina block with the same shape as the interior of the model as a center block above the bottom supporting block, wherein three center blocks are uniformly arranged in the middle of the model, side supporting blocks are uniformly arranged around the side part of each center block, the outer wall of the side part of each center block is close to the outer wall of the side part in the model, one end of each side supporting block is tightly attached to the inner wall of the model, and the other end of each side supporting block is tightly attached to the outer wall of the side part of the center block; one end of the side supporting block is tightly attached to the side outer wall of one center block of the model, and the other end of the side supporting block is tightly attached to the side outer wall of the other center block; (3) placing the upper die above the lower die, closing the die, filling a heat insulation layer II in the heat insulation box at the center of the outer part of the die, and finally, viewing from the side, wherein the heat insulation layer II is in an inverted isosceles trapezoid shape; (4) ventilating the interior of the model at the ventilation temperature of 100 ℃ and 150 ℃, and removing water and water vapor in the model; (5) and then pouring molten liquid from a pouring gate of the model, covering the upper end of the pouring gate of the model after the molten liquid is poured, covering the upper part of the model with a heat-insulating layer III, covering the upper cover of the heat-insulating box, and then naturally cooling and insulating.

Or the heat-preservation forming method of the fusion-cast high-purity alumina refractory product comprises the following steps:

(1) the upper die of the model is taken away, and the center block, the bottom supporting block and the like are arranged in the lower die of the model, and the method specifically comprises the following steps: the method comprises the following steps of firstly, placing a fused cast alumina block as a bottom supporting block for supporting a center block in the middle of the bottom of a lower die of a model, then placing a fused cast alumina block with the same shape as the interior of the model as a center block above the bottom supporting block, wherein three center blocks are uniformly arranged in the middle of the model, side supporting blocks are uniformly arranged around the side part of each center block, the outer wall of the side part of each center block is close to the outer wall of the side part in the model, one end of each side supporting block is tightly attached to the inner wall of the model, and the other end of each side supporting block is tightly attached to the outer wall of the side part of the center block; one end of the side supporting block is tightly attached to the side outer wall of one center block of the model, and the other end of the side supporting block is tightly attached to the side outer wall of the other center block; (2) placing the upper die above the lower die, and closing the dies; (3) arranging a heat preservation layer I at the bottom of the heat preservation box, then placing the model in the center of the upper part of the heat preservation layer I of the heat preservation box, then filling a heat preservation layer II in the heat preservation box at the center of the outer part of the model, and finally, viewing from the side, the heat preservation layer II is in an inverted isosceles trapezoid shape; (4) ventilating the interior of the model at the ventilation temperature of 100 ℃ and 150 ℃, and removing water and water vapor in the model; (5) and then pouring molten liquid from a pouring gate of the model, covering the upper end of the pouring gate of the model after the molten liquid is poured, covering the upper part of the model with a heat-insulating layer III, covering the upper cover of the heat-insulating box, and then naturally cooling and insulating.

For three different batches of melts, the heat-insulating layer I and the heat-insulating layer III in the above examples 1 to 4 are respectively the same, the thickness of the heat-insulating layer I is 250mm, the thickness of the heat-insulating layer III is 300mm, and the space in the model is the same. Examples 2-4 the insulating layer II is the same, and the thickness of the lowermost end of the insulating layer II in example 1 is the same as that of the insulating layer II in example 2, and the thickness is 200 mm. In example 2, the thickness of the uppermost layer II was 300 mm.

The starting time of the experiment is the same, the experimental environment is the same, finally the fused and cast high-purity alumina refractory product is obtained by natural cooling, heat preservation and molding, and then appearance detection and physical and chemical index detection are carried out.

The final product results for the three different melts were as follows:

in the embodiment 1, the surface of the sample is provided with air holes, and the interior of the sample is provided with more shrinkage cavities and cracks;

in the embodiment 2, the surface of the sample has no air holes, and the middle part of the upper part in the interior of the sample is provided with a shrinkage cavity and a crack;

in example 3, the surface of the sample has no pores, and the interior of the sample has no shrinkage cavity or crack;

in example 4, the surface of the sample has no pores, and the interior of the sample has no shrinkage cavity or crack.

While the preferred embodiments of the present invention have been described, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention.