Cooling device and method for large foamed aluminum preparation

Abstract

According to the cooling device and method for large foamed aluminum preparation, a traditional water spraying cooling mode is changed into an air blowing cooling mode, meanwhile, traditional overall water spraying cooling is changed into local air blowing cooling, the cooling structure of a tank car mold shell is further optimized, a heat preservation measure is additionally arranged in the cooling process, and the cooling efficiency is improved. The temperature distribution uniformity of the foamed aluminum melt is effectively improved, and the foamed aluminum melt is gradually solidified layer by layer from the upper side and the lower side to the middle part, so that the defects of holes and cracks are effectively reduced, meanwhile, the gravity drainage phenomenon is effectively weakened, the thickness of a solid aluminum layer of a foamed aluminum finished product is further reduced, and the production efficiency is improved. The method reduces the difficulty of subsequent processing and remelting, can also ensure that the top of a foamed aluminum finished product is flat and free of collapse, effectively improves the yield of the foamed aluminum finished product, reduces the quenching effect of the tank car die in an air blowing cooling mode, avoids large deformation of a tank car die shell, and further prolongs the service life of the tank car die.

Description

Technical Field

[0001] The invention belongs to the technical field of foam aluminum preparation, and in particular relates to a cooling device and method for preparing large foam aluminum. Background Art

[0002] Foamed aluminum is made by adding additives to pure aluminum or aluminum alloy and then undergoing a foaming process. It has the characteristics of both metal and bubbles. Foamed aluminum contains a large number of pores and has the characteristics of low density and large specific surface area. Since the pores of foamed aluminum are evenly distributed, it has the characteristics of light weight and high specific strength.

[0003] As a functional material, foam aluminum also has excellent properties such as vibration reduction, damping, sound absorption, fire prevention, energy absorption, and electromagnetic shielding. These properties make foam aluminum have broad application prospects in many fields such as aerospace, transportation, ship engineering, and construction. It is an engineering material with significant development prospects.

[0004] The melt foaming method is one of the mainstream methods for preparing foamed aluminum. It mixes and stirs the aluminum-based alloy and the foaming agent in a front crucible to form a melt, and then pours the formed melt into a tank truck mold for foaming and cooling until a foamed aluminum product is formed. Finally, the foamed aluminum product is taken out of the tank truck mold and cut into smaller foamed aluminum products.

[0005] During the preparation of foam aluminum, due to the presence of a large number of bubbles in the foam aluminum melt, it has a large specific surface area, and the bubbles tend to merge and rupture to reduce the system energy. Under the action of gravity, the aluminum liquid will continue to concentrate to the bottom. Therefore, in order to obtain a more uniform pore structure, the foam aluminum melt needs to be cooled quickly.

[0006] However, due to the presence of a large number of bubbles in the foamed aluminum melt and when the size of the foamed aluminum is large, it takes a long time for the foamed aluminum melt to be completely cooled.

[0007] However, the cooling structure and cooling method used in the existing tank car mold have obvious shortcomings. Specifically, the existing tank car mold usually uses water spray cooling to cool the entire tank car mold, which will cause the foam aluminum melt adjacent to the tank car mold shell to have a faster cooling rate, while the cooling rate of the center of the foam aluminum melt is slower, which will cause the temperature distribution of the foam aluminum melt to be uneven, resulting in inconsistent cooling and solidification time in different areas, which ultimately affects the shrinkage process, which is also the main reason for the existence of holes and cracks inside.

[0008] Furthermore, due to the uneven cooling and solidification of the foam aluminum melt, the gravity drainage phenomenon will be aggravated, which will eventually increase the thickness of the solid aluminum layer of the foam aluminum product, making subsequent processing and remelting difficult, and will also cause the top middle part of the foam aluminum product to collapse, thereby reducing the yield rate of the foam aluminum product. In addition, the tank car mold is prone to large deformation of the tank car mold shell under the rapid cooling effect of the water spray cooling method, which will further reduce the service life of the tank car mold. Summary of the invention

[0009] In view of the problems existing in the prior art, the present invention provides a cooling device and method for preparing large-scale foam aluminum, which changes the traditional water spray cooling method into a blowing cooling method, and at the same time changes the traditional overall water spray cooling into local blowing cooling, and further optimizes the cooling structure of the tank truck mold shell, and also adds insulation measures during the cooling process, effectively improving the temperature distribution uniformity of the foam aluminum melt, so that the foam aluminum melt is gradually solidified layer by layer from the upper and lower sides to the middle part, thereby effectively reducing the generation of holes and crack defects, and at the same time effectively weakening the gravity drainage phenomenon, further reducing the thickness of the solid aluminum layer of the foam aluminum product, reducing the difficulty of subsequent processing and remelting, and can also ensure that the top of the foam aluminum product is flat and without collapse, effectively improving the yield rate of the foam aluminum product, and reducing the rapid cooling effect of the tank truck mold under the blowing cooling method, avoiding large deformation of the tank truck mold shell, thereby further improving the service life of the tank truck mold.

[0010] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a cooling device for preparing large-scale foamed aluminum, comprising a slot truck mold, a first cooling air unit and a second cooling air unit; the slot truck mold is located on a roller conveyor belt, one end of the roller conveyor belt extends into an insulation chamber, and the other end of the roller conveyor belt passes through a cold zone operating station and a product processing station in sequence; the first cooling air unit and the second cooling air unit are both located at the cold zone operating station, the first cooling air unit is arranged below the roller conveyor belt, and the second cooling air unit is arranged above the roller conveyor belt; the inner cavity of the slot truck mold serves as a molding cavity for the foamed aluminum finished product.

[0011] The tank car mold includes a shell and a cover plate, which is snap-fitted and installed at the open part above the shell. A cover plate gate is opened at the edge of the cover plate, and a splash guard is fixedly arranged on the upper surface of the cover plate around the cover plate gate; an outward-inclined shell gate is arranged at the top of the shell side wall opposite to the cover plate gate; thermal insulation cotton positioning slots are fixedly arranged on the outer facades of the four side walls of the shell, and the thermal insulation cotton positioning slots are used to install thermal insulation cotton.

[0012] A grid partition plate is fixedly arranged on the upper surface of the bottom plate of the shell, the plate body thickness of the grid partition plate is 3mm-5mm, and the plate body height of the grid partition plate is 20mm-50mm.

[0013] A heat sink group is fixedly arranged on the lower surface of the shell, and the heat sink group contains a total of nine heat sinks. The nine heat sinks are distributed in parallel with equal intervals along the length direction of the shell, and the nine heat sinks have the same length; in the length direction of the shell, the nine heat sinks are sequentially recorded as heat sink No. 1, heat sink No. 2, heat sink No. 3, heat sink No. 4, heat sink No. 5, heat sink No. 6, heat sink No. 7, heat sink No. 8 and heat sink No. 9; the height and thickness of heat sink No. 1, heat sink No. 5 and heat sink No. 9 are the same, and the height is 25mm-30mm, and the thickness is 8mm-10mm; the height and thickness of heat sink No. 3 and heat sink No. 7 are the same, and the height is 47mm-50mm, and the thickness is 18mm-22mm; the height and thickness of heat sink No. 2, heat sink No. 4, heat sink No. 6 and heat sink No. 8 are the same, and the height is 38mm-42mm, and the thickness is 14mm-16mm.

[0014] A protective baffle is fixedly arranged on the edge of the lower surface of the shell, the heat sink group is located on the inner side of the protective baffle, and a gap of 50mm to 70mm is left between the surrounding of the heat sink group and the protective baffle.

[0015] The blowing direction of the first cooling air unit forms an angle of 30° to 45° with the plane where the heat sink group is located, and the distance between the first cooling air unit and the lower edge surface of the protective baffle is 0.3m to 0.5m; the blowing direction of the second cooling air unit forms an angle of 75° to 90° with the plane where the cover plate is located, and the distance between the second cooling air unit and the upper surface of the cover plate is 0.8m to 1.2m.

[0016] A robotic arm is arranged at the cold zone operating station, and the thermal insulation cotton is installed into the thermal insulation cotton positioning slot through the robotic arm.

[0017] The shell adopts a rectangular box structure, the length of the shell is 180cm~210cm, the width of the shell is 120cm~140cm, the height of the shell is 25cm~28cm, and the wall thickness of the shell is 10mm~15mm; the cover plate adopts a rectangular plate structure, the length of the cover plate is 180cm~210cm, the width of the shell is 120cm~140cm, and the thickness of the cover plate is 5mm~10mm.

[0018] The thermal insulation cotton adopts a rectangular plate structure. The length and width of the thermal insulation cotton are determined according to the size of the outer facade of the shell side wall where it is located. The thickness of the thermal insulation cotton is 20mm to 30mm.

[0019] A method for preparing large-scale foamed aluminum, using the cooling device for preparing large-scale foamed aluminum, comprises the following steps:

[0020] Step 1: Insulation foaming

[0021] The tank car mold is parked in the middle of the insulation chamber, so that the foamed aluminum melt in the tank car mold is foamed in the insulation chamber environment. During the foaming process, the ambient temperature of the insulation chamber is controlled at 660℃~700℃ and maintained stable. The foaming duration is 16min~30min, so that the foaming height of the foamed aluminum melt is between 200mm~350mm. In addition, the insulation chamber can be adjusted by normal pressure, 5MPa~7MPa nitrogen pressure adjustment or vacuum negative pressure adjustment according to actual production needs;

[0022] Step 2: Workstation transfer

[0023] When the heat preservation and foaming process of the foamed aluminum melt is completed, the hatch of the heat preservation chamber is first opened, and then the roller conveyor is started, and the tank car mold is moved to the cold zone operating station at a speed of 2m / min to 8m / min;

[0024] Step 3: Keep warm before cooling

[0025] When the tank car mold reaches the cold zone operation station, the robotic arm is started, and the pre-prepared insulation cotton is placed one by one into the insulation cotton positioning slot through the robotic arm, so that the insulation cotton forms an insulation layer around the shell, and the installation of the insulation cotton needs to be completed within 10s to 15s;

[0026] Step 4: Blow air to cool

[0027] Within 5s to 10s after the installation of the thermal insulation cotton, the first cooling air unit and the second cooling air unit are started synchronously. The bottom of the tank car mold is cooled by the first cooling air unit, and the top of the tank car mold is cooled by the second cooling air unit. The cooling process lasts for 20min to 40min. After the cooling process, the tank car mold is cooled naturally.

[0028] Step 5: Cooling and temperature measurement

[0029] Within 5s to 10s after the air cooling is started, the top, bottom and central areas of the tank car mold are measured in real time using thermocouples. When the temperature of the insulation cotton in the central area around the tank car mold is lower than 100°C, the temperature measurement ends.

[0030] Step 6: Product processing

[0031] When the temperature measurement is completed, the roller conveyor is started again, and the tank car mold is moved to the product processing station at a speed of 4m / min to 6m / min. The foam aluminum product is then taken out from the inner cavity of the tank car mold, and then the foam aluminum product is inspected and cut according to actual production needs.

[0032] Beneficial effects of the present invention:

[0033] The cooling device and method for preparing large-scale foam aluminum of the present invention change the traditional water spray cooling method into a blowing cooling method, and change the traditional overall water spray cooling into local blowing cooling, and further optimize the cooling structure of the tank truck mold shell, and also add insulation measures in the cooling process, effectively improving the temperature distribution uniformity of the foam aluminum melt, so that the foam aluminum melt can be gradually solidified layer by layer from the upper and lower sides to the middle part, thereby effectively reducing the generation of holes and crack defects, and effectively weakening the gravity drainage phenomenon, further reducing the thickness of the solid aluminum layer of the foam aluminum product, reducing the difficulty of subsequent processing and remelting, and can also ensure that the top of the foam aluminum product is flat and without collapse, effectively improving the yield rate of the foam aluminum product, and reducing the rapid cooling effect of the tank truck mold under the blowing cooling method, avoiding large deformation of the tank truck mold shell, thereby further improving the service life of the tank truck mold. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 A schematic diagram of the structure of a tank car mold of a cooling device for preparing large-scale foamed aluminum according to the present invention (viewing angle 1);

[0035] Figure 2 A schematic diagram of a tank car mold structure of a cooling device (cover plate not shown) for preparing large-scale foamed aluminum according to the present invention (viewing angle 2);

[0036] Figure 3 A schematic diagram of the structure of a tank car mold of a cooling device for preparing large-scale foamed aluminum according to the present invention (viewing angle 3);

[0037] In the figure, 1 is a shell, 2 is a cover plate, 3 is a cover plate gate, 4 is a splash guard, 5 is a shell gate, 6 is a thermal insulation cotton positioning slot, 7 is a thermal insulation cotton, 8 is a grid partition plate, 9 is a heat sink group, and 10 is a protective baffle. DETAILED DESCRIPTION

[0038] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0039] A cooling device for preparing large foamed aluminum comprises a tank truck mold, a first cooling air unit and a second cooling air unit; the tank truck mold is located on a roller conveyor, one end of the roller conveyor extends into an insulation chamber, and the other end of the roller conveyor passes through a cold zone operating station and a product processing station in sequence; the first cooling air unit and the second cooling air unit are both located at the cold zone operating station, the first cooling air unit is arranged below the roller conveyor, and the second cooling air unit is arranged above the roller conveyor; the inner cavity of the tank truck mold serves as a molding cavity for a foamed aluminum finished product.

[0040] Specifically, the selection criteria for the tank car mold are materials that are resistant to high temperatures and have thermal conductivity, preferably SKD61 cast steel; the number of cooling fans in the first cooling air unit and the second cooling air unit are preferably 2 to 4.

[0041] like Figures 1 to 3 As shown, the tank truck mold includes a shell 1 and a cover plate 2, the cover plate 2 is snap-fitted and installed at the open part above the shell 1, a cover plate gate 3 is opened at the edge of the cover plate 2, and a splash guard 4 is fixedly arranged on the upper surface of the cover plate 2 in the circumferential direction of the cover plate gate 3; an outward-inclined shell gate 5 is arranged at the top of the shell 1 side wall opposite to the cover plate gate 3; thermal insulation cotton positioning slots 6 are fixedly arranged on the outer facades of the four side walls of the shell 1, and the thermal insulation cotton positioning slots 6 are used to install thermal insulation cotton 7.

[0042] Specifically, there are eight thermal insulation cotton positioning slots 6, two of which are arranged on each side wall facade of the shell 1. The two thermal insulation cotton positioning slots 6 are in a right angle shape and are distributed opposite each other. The thermal insulation cotton 7 is positioned by the two opposite thermal insulation cotton positioning slots 6, and the thermal insulation cotton 7 can be tightly attached to the side wall facade of the shell 1.

[0043] A grid partition plate 8 is fixedly arranged on the upper surface of the bottom plate of the shell 1 . The thickness of the grid partition plate 8 is 3 mm to 5 mm, and the height of the grid partition plate 8 is 20 mm to 50 mm.

[0044] Specifically, the grid partition plate 8 has twelve grids, the twelve grids have exactly the same size, and are composed of three long boards and eight short boards.

[0045] A heat sink group 9 is fixedly arranged on the lower surface of the shell 1, and the heat sink group 9 contains a total of nine heat sinks, which are distributed in parallel with equal intervals along the length direction of the shell 1, and the nine heat sinks have the same length; in the length direction of the shell 1, the nine heat sinks are sequentially recorded as heat sink No. 1, heat sink No. 2, heat sink No. 3, heat sink No. 4, heat sink No. 5, heat sink No. 6, heat sink No. 7, heat sink No. 8 and heat sink No. 9; the height and thickness of the heat sink No. 1, heat sink No. 5 and heat sink No. 9 are the same, and the height is 25mm-30mm, and the thickness is 8mm-10mm; the height and thickness of the heat sink No. 3 and heat sink No. 7 are the same, and the height is 47mm-50mm, and the thickness is 18mm-22mm; the height and thickness of the heat sink No. 2, heat sink No. 4, heat sink No. 6 and heat sink No. 8 are the same, and the height is 38mm-42mm, and the thickness is 14mm-16mm.

[0046] A protective baffle 10 is fixedly provided on the lower surface edge of the housing 1 , the heat sink group 9 is located inside the protective baffle 10 , and a gap of 50 mm to 70 mm is left around the heat sink group 9 and the protective baffle 10 .

[0047] The blowing direction of the first cooling air unit forms an angle of 30° to 45° with the plane where the heat sink group 9 is located, and the distance between the first cooling air unit and the lower edge surface of the protective baffle 10 is 0.3m to 0.5m; the blowing direction of the second cooling air unit forms an angle of 75° to 90° with the plane where the cover plate 2 is located, and the distance between the second cooling air unit and the upper surface of the cover plate 2 is 0.8m to 1.2m.

[0048] Specifically, after the first cooling air unit starts blowing, the cooling air can be blown from obliquely below to the heat sink group 9, so that the cooling air can flow quickly between the heat sinks of the heat sink group 9, thereby achieving efficient heat exchange between the cooling air and the heat sink group 9, while avoiding the rapid cooling effect, and by controlling the direction of the fan, the cooling air can flexibly circulate from all directions and act on the entire bottom area of ​​the bottom of the shell 1, which can not only ensure the uniformity of cooling, but also accelerate the heat conduction efficiency of the bottom of the shell 1, and finally effectively improve the overall cooling of the bottom of the foamed aluminum melt in the inner cavity of the shell 1. After the second cooling air unit starts blowing, the cooling air is directly blown to the cover plate 2, so that the cooling air and the cover plate 2 can achieve efficient heat exchange, thereby achieving overall cooling of the top of the foamed aluminum melt in the inner cavity of the shell 1, and finally achieving the layer-by-layer solidification of the foamed aluminum melt from the upper and lower sides to the middle part.

[0049] A robotic arm is arranged at the cold zone operating station, and the thermal insulation cotton 7 is installed into the thermal insulation cotton positioning slot 6 through the robotic arm.

[0050] The shell 1 adopts a rectangular box structure, the length of the shell 1 is 180cm~210cm, the width of the shell 1 is 120cm~140cm, the height of the shell 1 is 25cm~28cm, and the wall thickness of the shell 1 is 10mm~15mm; the cover plate 2 adopts a rectangular plate structure, the length of the cover plate 2 is 180cm~210cm, the width of the shell 1 is 120cm~140cm, and the plate thickness of the cover plate 2 is 5mm~10mm.

[0051] The thermal insulation cotton 7 adopts a rectangular plate structure. The length and width of the thermal insulation cotton 7 are determined according to the size of the outer facade of the side wall of the shell 1 where it is located. The thickness of the thermal insulation cotton 7 is 20mm to 30mm.

[0052] Specifically, the selection criteria for the thermal insulation cotton 7 are materials with high-efficiency thermal insulation properties, preferably rock wool; and the sizes of the thermal insulation cotton 7 are two large and two small. The two large-sized thermal insulation cottons 7 have the same size specifications, and the two small-sized thermal insulation cottons 7 differ only in width. The width of the small-sized thermal insulation cotton 7 located below the shell gate 5 is slightly smaller.

[0053] A method for preparing large-scale foamed aluminum, using the cooling device for preparing large-scale foamed aluminum, comprises the following steps:

[0054] Step 1: Insulation foaming

[0055] The tank car mold is parked in the middle of the insulation chamber, so that the foamed aluminum melt in the tank car mold is foamed in the insulation chamber environment. During the foaming process, the ambient temperature of the insulation chamber is controlled at 660℃~700℃ and maintained stable. The foaming duration is 16min~30min, so that the foaming height of the foamed aluminum melt is between 200mm~350mm. In addition, the insulation chamber can be adjusted by normal pressure, 5MPa~7MPa nitrogen pressure adjustment or vacuum negative pressure adjustment according to actual production needs;

[0056] Step 2: Workstation transfer

[0057] When the heat preservation and foaming process of the foamed aluminum melt is completed, the hatch of the heat preservation chamber is first opened, and then the roller conveyor is started, and the tank car mold is moved to the cold zone operating station at a speed of 2m / min to 8m / min;

[0058] Step 3: Keep warm before cooling

[0059] When the tank car mold reaches the cold zone operation station, the mechanical arm is started, and the pre-prepared insulation cotton 7 is placed one by one into the insulation cotton positioning slot 6 by the mechanical arm, so that the insulation cotton 7 forms an insulation layer around the shell 1, and the installation of the insulation cotton 7 needs to be completed within 10s to 15s;

[0060] Step 4: Blow air to cool

[0061] Within 5s to 10s after the installation of the thermal insulation cotton 7 is completed, the first cooling air unit and the second cooling air unit are started synchronously, the bottom of the tank car mold is cooled by the first cooling air unit, and the top of the tank car mold is cooled by the second cooling air unit. The cooling process lasts for 20min to 40min. After the cooling process is completed, the tank car mold is cooled naturally.

[0062] Step 5: Cooling and temperature measurement

[0063] Within 5s to 10s after the air cooling is started, the top, bottom and central areas of the tank car mold are measured in real time using thermocouples. When the temperature of the insulation cotton 7 in the central area around the tank car mold is lower than 100°C, the temperature measurement ends;

[0064] Step 6: Product processing

[0065] When the temperature measurement is completed, the roller conveyor is started again, and the tank car mold is moved to the product processing station at a speed of 4m / min to 6m / min. The foam aluminum product is then taken out from the inner cavity of the tank car mold, and then the foam aluminum product is inspected and cut according to actual production needs.

[0066] The solutions in the embodiments are not intended to limit the protection scope of the present invention. All equivalent implementations or changes that do not deviate from the present invention are included in the protection scope of the present invention.

Claims

1. A cooling device for preparing large-scale foamed aluminum, characterized in that: It includes a tank truck mold, a first cooling air unit and a second cooling air unit; the tank truck mold is located on a roller conveyor, one end of the roller conveyor extends into the insulation chamber, and the other end of the roller conveyor passes through a cold zone operating station and a product processing station in sequence; the first cooling air unit and the second cooling air unit are both located in the cold zone operating station, the first cooling air unit is arranged below the roller conveyor, and the second cooling air unit is arranged above the roller conveyor; the inner cavity of the tank truck mold serves as a molding cavity for a foamed aluminum product.

2. A cooling device for preparing large-scale foamed aluminum according to claim 1, characterized in that: The tank car mold includes a shell and a cover plate, which is snap-fitted and installed at the open part above the shell. A cover plate gate is opened at the edge of the cover plate, and a splash guard is fixedly arranged on the upper surface of the cover plate around the cover plate gate; an outward-inclined shell gate is arranged at the top of the shell side wall opposite to the cover plate gate; thermal insulation cotton positioning slots are fixedly arranged on the outer facades of the four side walls of the shell, and the thermal insulation cotton positioning slots are used to install thermal insulation cotton.

3. A cooling device for preparing large-scale foamed aluminum according to claim 2, characterized in that: A grid partition plate is fixedly arranged on the upper surface of the bottom plate of the shell, the plate body thickness of the grid partition plate is 3mm-5mm, and the plate body height of the grid partition plate is 20mm-50mm.

4. A cooling device for preparing large-scale foamed aluminum according to claim 2, characterized in that: A heat sink group is fixedly arranged on the lower surface of the shell, and the heat sink group contains a total of nine heat sinks. The nine heat sinks are distributed in parallel with equal intervals along the length direction of the shell, and the nine heat sinks have the same length; in the length direction of the shell, the nine heat sinks are sequentially recorded as heat sink No. 1, heat sink No. 2, heat sink No. 3, heat sink No. 4, heat sink No. 5, heat sink No. 6, heat sink No. 7, heat sink No. 8 and heat sink No. 9; the height and thickness of heat sink No. 1, heat sink No. 5 and heat sink No. 9 are the same, and the height is 25mm-30mm, and the thickness is 8mm-10mm; the height and thickness of heat sink No. 3 and heat sink No. 7 are the same, and the height is 47mm-50mm, and the thickness is 18mm-22mm; the height and thickness of heat sink No. 2, heat sink No. 4, heat sink No. 6 and heat sink No. 8 are the same, and the height is 38mm-42mm, and the thickness is 14mm-16mm.

5. A cooling device for preparing large-scale foamed aluminum according to claim 4, characterized in that: A protective baffle is fixedly arranged on the edge of the lower surface of the shell, the heat sink group is located on the inner side of the protective baffle, and a gap of 50mm to 70mm is left between the surrounding of the heat sink group and the protective baffle.

6. A cooling device for preparing large-scale foamed aluminum according to claim 5, characterized in that: The blowing direction of the first cooling air unit forms an angle of 30° to 45° with the plane where the heat sink group is located, and the distance between the first cooling air unit and the lower edge surface of the protective baffle is 0.3m to 0.5m; the blowing direction of the second cooling air unit forms an angle of 75° to 90° with the plane where the cover plate is located, and the distance between the second cooling air unit and the upper surface of the cover plate is 0.8m to 1.2m.

7. A cooling device for preparing large-scale foamed aluminum according to claim 2, characterized in that: A robotic arm is arranged at the cold zone operating station, and the thermal insulation cotton is installed into the thermal insulation cotton positioning slot through the robotic arm.

8. The cooling device for preparing large-scale foamed aluminum according to claim 2, characterized in that: The shell adopts a rectangular box structure, the length of the shell is 180cm~210cm, the width of the shell is 120cm~140cm, the height of the shell is 25cm~28cm, and the wall thickness of the shell is 10mm~15mm; the cover plate adopts a rectangular plate structure, the length of the cover plate is 180cm~210cm, the width of the shell is 120cm~140cm, and the thickness of the cover plate is 5mm~10mm.

9. A cooling device for preparing large-scale foamed aluminum according to claim 2, characterized in that: The thermal insulation cotton adopts a rectangular plate structure. The length and width of the thermal insulation cotton are determined according to the size of the outer facade of the shell side wall where it is located. The thickness of the thermal insulation cotton is 20mm to 30mm.

10. A method for preparing large-scale foamed aluminum, using the cooling device for preparing large-scale foamed aluminum according to claim 1, characterized in that: The steps include: Step 1: Insulation foaming The tank car mold is parked in the middle of the insulation chamber, so that the foamed aluminum melt in the tank car mold is foamed in the insulation chamber environment. During the foaming process, the ambient temperature of the insulation chamber is controlled at 660℃~700℃ and maintained stable. The foaming duration is 16min~30min, so that the foaming height of the foamed aluminum melt is between 200mm~350mm. In addition, the insulation chamber can be adjusted by normal pressure, 5MPa~7MPa nitrogen pressure adjustment or vacuum negative pressure adjustment according to actual production needs; Step 2: Workstation transfer When the heat preservation and foaming process of the foamed aluminum melt is completed, the hatch of the heat preservation chamber is first opened, and then the roller conveyor is started, and the tank car mold is moved to the cold zone operating station at a speed of 2m / min to 8m / min; Step 3: Keep warm before cooling When the tank car mold reaches the cold zone operation station, the robotic arm is started, and the pre-prepared insulation cotton is placed one by one into the insulation cotton positioning slot through the robotic arm, so that the insulation cotton forms an insulation layer around the shell, and the installation of the insulation cotton needs to be completed within 10s to 15s; Step 4: Blow air to cool Within 5s to 10s after the installation of the thermal insulation cotton, the first cooling air unit and the second cooling air unit are started synchronously. The bottom of the tank car mold is cooled by the first cooling air unit, and the top of the tank car mold is cooled by the second cooling air unit. The cooling process lasts for 20min to 40min. After the cooling process, the tank car mold is cooled naturally. Step 5: Cooling and temperature measurement Within 5s to 10s after the air cooling is started, the top, bottom and central areas of the tank car mold are measured in real time using thermocouples. When the temperature of the insulation cotton in the central area around the tank car mold is lower than 100°C, the temperature measurement ends. Step 6: Product processing When the temperature measurement is completed, the roller conveyor is started again, and the tank car mold is moved to the product processing station at a speed of 4m / min to 6m / min. The foam aluminum product is then taken out from the inner cavity of the tank car mold, and then the foam aluminum product is inspected and cut according to actual production needs.

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