Die for die casting process

Abstract

The utility model relates to a mold for a mold casting process. The mold comprises a mold body and a riser assembly. An inner cavity is formed in the mold body. The riser assembly comprises a shell, a heat insulation plate and a heat insulation filling body. The lower end of the shell is fixedly connected with the upper side of the mold body. A step is formed around the inner wall of the inner cavity at the joint of the shell and the inner cavity. The heat insulation plate is of an integrally-formed cylindrical structure. The lower side edge of the heat insulation plate abuts against the step. And a riser is enclosed in the heat insulation plate. And the risers are vertically through. The lower end opening of the riser communicates with the inner cavity, and the upper end opening communicates with the outside. The heat insulation filling body is filled between the inner wall of the shell and the outer wall of the heat insulation plate and is of a block-shaped structure formed by curing phenolic resin sand. The heat insulation plate is integrally placed on the step, the space between the outer wall of the heat insulation plate and the inner wall of the riser is filled with the heat insulation filling body formed by ramming and solidifying the knotting material, the structure is simple, and installation is easy and convenient. And due to the support of the heat insulation filling body, the heat insulation plate is not easy to deform in the use process.

Description

Technical Field

[0001] The utility model relates to the technical field of heat preservation of mold casting risers, in particular to a mold for mold casting process. Background Technique

[0002] During the solidification process of an ingot, due to the shrinkage characteristics of the alloy, the volume of the ingot will decrease, resulting in problems such as dimensional deviation, irregular shape, and internal defects, such as shrinkage cavities and shrinkage porosity. These problems will seriously affect the profile accuracy and performance stability of the ingot. Therefore, the main purpose of feeding is to offset this shrinkage deformation and ensure the quality of the ingot.

[0003] A riser is an additional part specifically provided on the ingot for feeding. It can continuously provide liquid metal for the ingot during the solidification process of the ingot, thereby filling the cavities generated due to shrinkage. The design of the riser needs to consider factors such as the shrinkage characteristics of the alloy, the structure and size of the ingot, etc.

[0004] In metallurgical enterprises, the mold casting process is an important part of metal solidification forming, and most of its products are high-value-added products. As the feeding function of the heat preservation riser, which directly affects the effective utilization rate and quality of molten steel, is crucial.

[0005] In order to extend the solidification time of liquid metal and improve the feeding efficiency of the ingot, it is necessary to heat-preserve the riser. In the prior art, the riser generally consists of a cap shell and a heat-insulating board. The heat-insulating board generally consists of multiple hanging boards and inserting boards. The heat-insulating board is inserted into the upper opening of the cap shell (or ingot mold) and assembled on the side wall of the cap shell (or ingot mold). During the pouring process, the heat-insulating board and the head of the ingot form a heat preservation area. However, due to manufacturing errors of the heat-insulating board and the easy deformation of the cap shell during use, the heat-insulating board is likely to loosen and generate ingot gaps during the pouring process, resulting in "floating board" or "drilling into steel", which seriously damages the heat preservation conditions of the head of the ingot. Content of the Utility Model

[0006] In order to improve the heat preservation conditions of the head of the ingot, this application provides a mold for mold casting process.

[0007] The mold for mold casting process provided by the utility model adopts the following technical solutions:

[0008] A mold for die casting process, comprising a mold body and a riser assembly; wherein, a cavity is formed inside the mold body; the riser assembly includes a housing, a heat insulation board and a heat insulation filler; the housing is of a hollow structure, the lower end is fixedly connected to the upper side of the mold body, and the upper end is open; at the connection between the housing and the cavity, a step is formed around the inner wall of the cavity; the step surface of the step faces upward; the heat insulation board is an integrally formed cylindrical structure; the lower side edge of the heat insulation board abuts against the step; a riser is formed inside the heat insulation board; the riser is vertically through; the lower end opening of the riser is communicated with the cavity, and the upper end opening is communicated with the outside, and the molten steel for feeding flows into the cavity through the riser; the heat insulation filler is filled between the inner wall of the housing and the outer wall of the heat insulation board, and is a block structure formed by curing phenolic resin sand.

[0009] Optionally, the fineness of the phenolic resin sand is 50 mesh - 100 mesh.

[0010] Optionally, the curing time of the phenolic resin sand is 1 min - 60 min.

[0011] Optionally, the cavity gradually narrows along the direction from the outside to the cavity.

[0012] Optionally, the width of the gap between the outer wall of the heat insulation board and the inner wall of the riser is between 10 mm and 15 mm.

[0013] Optionally, the side of the heat insulation board away from the step is flush with the edge of the opening of the riser away from the cavity.

[0014] Optionally, the width of the step is between 15 mm and 30 mm.

[0015] Optionally, the wall thickness of the heat insulation board is 30 mm - 100 mm.

[0016] As described above, the mold for die casting process of the present utility model has at least the following beneficial effects:

[0017] 1. Compared with the existing riser heat preservation technology, in the mold for die casting process of the present application, the heat insulation board is integrally placed on the step, and a heat insulation filler formed by ramming and curing phenolic resin sand is filled between the outer wall of the heat insulation board and the inner wall of the housing. The structure is simple and the installation is convenient. And due to the support of the heat insulation filler, the heat insulation board is not easily deformed during use, and thus is not easily loosened to generate ingot gaps during pouring, will not cause floating plates and drilling steel, has a good heat preservation effect, and effectively ensures the heat preservation conditions at the head of the ingot.

[0018] 2. Since the mold for the die casting process of this application is easy to install, the safety risks caused by high altitude and high temperature that the staff need to bear are less. This can not only improve production efficiency, but also be beneficial to personal safety, and can also reduce the damage of the insulation board during installation. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a cross-sectional view of an embodiment of the present utility model for showing the overall structure of the mold for the die casting process.

[0020] Figure 2 is a cross-sectional view of an embodiment of the present utility model for showing the stepped structure.

[0021] Figure 3 is a schematic diagram of an embodiment of the present utility model for showing the structure of the insulation board.

[0022] Reference numerals: 1, mold body; 2, inner cavity; 3, riser; 4, step; 5, insulation board; 6, heat insulation filler; 7, outer shell. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] The following specific examples illustrate the embodiments of the present utility model. Those skilled in the art can easily understand other advantages and effects of the present utility model from the content disclosed in this specification. The present utility model can also be implemented or applied through other different specific embodiments. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present utility model. It should be noted that, without conflict, the following embodiments and the features in the embodiments can be combined with each other. It should also be understood that the terms used in the embodiments of the present utility model are for describing specific implementation schemes, rather than for limiting the protection scope of the present utility model. The test methods without specific conditions noted in the following embodiments are usually in accordance with conventional conditions or in accordance with the conditions recommended by each manufacturer.

[0024] It should be noted that the structures, ratios, sizes, etc. shown in the drawings of this specification are only used to cooperate with the content disclosed in the specification for those skilled in this technology to understand and read, and are not used to limit the limited conditions under which the present utility model can be implemented. Therefore, they do not have technical essence. Any modification of the structure, change of the proportional relationship, or adjustment of the size, without affecting the effects that the present utility model can produce and the purposes that can be achieved, should still fall within the scope covered by the technical content disclosed in the present utility model. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" used in this specification are only for the convenience of clear narration, rather than for limiting the scope under which the present utility model can be implemented. The change or adjustment of their relative relationships, without substantial change of the technical content, should also be regarded as the scope under which the present utility model can be implemented.

[0025] Please refer to Figures 1-3 , this application discloses a mold for die-casting process, which includes a mold body 1 and a riser assembly.

[0026] There is an inner cavity 2 in the mold body 1. The inner cavity 2 is located within the mold body 1 and is used to hold molten steel so that the molten steel cools and solidifies therein.

[0027] The riser assembly includes a housing 7, a heat-insulating plate 5 and a heat-insulating filler 6. The housing 7 is fixedly connected (by welding, integral molding, etc.) to the upper side of the mold body 1, that is, the mold for the die-casting process of the present utility model is an integral mold.

[0028] The heat-insulating plate 5 is a tubular structure formed integrally. An inner riser 3 is formed inside the heat-insulating plate 5. The riser 3 penetrates through from top to bottom. The lower opening of the riser 3 communicates with the inner cavity 2, and the upper opening communicates with the outside. The molten steel for feeding flows into the inner cavity 2 through the riser, which is used to supplement the molten steel in the inner cavity 2 to prevent shrinkage cavities, shrinkage porosity, exhaust gas and slag collection in the ingot.

[0029] Please refer to Figure 1 、 Figure 2 , at the connection between the housing 7 and the inner cavity 2, a step 4 is formed around the inner wall of the inner cavity 2. The step 4 faces away from the opening of the inner cavity 2 of the riser 3 (i.e., upward). In Figure 1 、 Figure 2 , the size of the lower opening of the riser 3 is larger than the size of the opening where the inner cavity 2 communicates with the riser 3, forming the step 4.

[0030] Specifically, the opening shapes of both the riser 3 and the inner cavity 2 can be circular, or other suitable shapes, such as rectangular. In this embodiment, the opening shapes of both the riser 3 and the inner cavity 2 are rectangular, and the step 4 is in the shape of a square ring.

[0031] The riser assembly includes a heat-insulating plate 5 and a heat-insulating filler 6. Specifically, the heat-insulating plate 5 is integrally formed and has a shape adapted to the shape of the housing 7 so that the heat-insulating plate 5 can be placed into the housing 7. Therefore, the heat-insulating plate 5 is tubular. That is, the heat-insulating plate 5 is hollow in the middle and its shape varies according to the opening shape of the riser 3. In this embodiment, the heat-insulating plate 5 is a hollow cylinder with a square-ring cross-section. The lower edge of the heat-insulating plate 5 abuts against the step 4.

[0032] The thickness of the heat-insulating plate 5 is 30 mm - 100 mm. For example, it can be 30 mm, 50 mm, 70 mm, 100 mm. The specific thickness of the heat-insulating plate 5 needs to be selected according to the size of the ingot produced by the mold body 1.

[0033] Supported by the step 4, the integral heat insulation plate 5 can be installed in place quickly and efficiently. Compared with the existing spliced heat insulation materials, it is not only easy to install, but also has better heat insulation effect. In order to firmly support the heat insulation plate 5 and not prevent the molten steel from entering the inner cavity 2, the width of the step 4 is between 15 mm and 30 mm. For example, it can be 15 mm, 20 mm, 25 mm, 30 mm. Preferably, in this embodiment, the width of the step 4 is 25 mm.

[0034] More specifically, please refer to Figure 1 , 2 , the inner edge of the lower side of the heat insulation plate 5 is chamfered, and the chamfering angle can be 45°, so that a groove is formed on the lower side of the heat insulation plate 5, thereby preventing the protective slag from accumulating at the joint of the heat insulation plate 5 and the step 4 during the pouring process.

[0035] The heat insulation filler 6 is filled in the gap between the outer wall of the heat insulation plate 5 and the inner wall of the outer shell 7. The heat insulation filler 6 can support the heat insulation plate 5, make the heat insulation plate 5 loose and not easily deformed, and can also play a role in further improving the heat insulation effect of the riser 3.

[0036] Specifically, the whole of the heat insulation plate 5 can be in the shape of a cuboid or a frustum of a cone. When the heat insulation plate 5 is in the shape of a frustum of a cone, the size of the upper opening of the heat insulation plate 5 is smaller than that of the lower opening. At the same pouring height, the riser ratio of the frustum-shaped heat insulation plate 5 is 1% - 3% lower than that of the cuboid-shaped heat insulation plate 5. In this embodiment, the heat insulation plate 5 is selected to be in the shape of a frustum of a cone.

[0037] If the upper side of the heat insulation plate 5 is lower than the upper opening of the riser 3, it may cause the molten steel to directly contact the heat insulation filler 6, resulting in damage to the heat insulation filler 6. If the upper side of the heat insulation plate 5 is higher than the upper opening of the riser 3, it will increase the riser ratio and cause waste of molten steel. Therefore, please refer to Figure 1 , 2 , the side of the heat insulation plate 5 away from the step 4 (i.e., the upper side) is flush with the edge of the opening of the riser 3 away from the inner cavity 2 (i.e., the upper opening).

[0038] It should be noted that the riser ratio refers to the percentage of the volume of the heat insulation riser part at the head of the ingot in the volume of the whole ingot. A larger riser ratio is beneficial for sufficient feeding, while a smaller riser ratio is beneficial for improving the material utilization rate. In actual production, it needs to be selected according to the production conditions and quality requirements.

[0039] The heat-insulating filler 6 can be a block structure formed by curing ramming material. The ramming material is granular material, which can be cured into a block structure after ramming. It can be phenolic resin sand, urea-formaldehyde resin sand or epoxy resin sand. However, since formaldehyde is released during the use of urea-formaldehyde resin sand, which is not environmentally friendly, and since epoxy resin sand is flammable and sensitizing, phenolic resin sand is selected as the ramming material in the mold for the die-casting process of the present utility model. The phenolic resin sand is made by mixing phenolic resin, curing agent and sand in proportion.

[0040] Specifically, the fineness of the phenolic resin sand has a great influence on both the performance and cost of the heat-insulating filler 6. When the fineness of the phenolic resin sand is too large, the phenolic resin sand is not easy to ram, and there may be gaps inside the heat-insulating filler 6 formed after curing, resulting in poor heat-insulating performance of the heat-insulating filler 6. And the cost of the ramming material gradually increases with the decrease of its fineness. Considering the cost of the heat-insulating filler 6, the fineness of the ramming material should not be too fine. Therefore, the fineness of the ramming material is 50 mesh - 100 mesh. For example, it can be 50 mesh, 60 mesh, 70 mesh, 80 mesh, 90 mesh, 100 mesh. In this embodiment, 50 mesh is preferably selected.

[0041] The curing time of the phenolic resin sand has a great influence on the performance of the heat-insulating filler 6 and the production efficiency of the riser assembly. When the curing time of the phenolic resin sand is too short, the phenolic resin sand is not completely cured, and the mechanical properties and thermal stability of the finally formed heat-insulating filler 6 are both poor. When the curing time of the phenolic resin sand is too short, a longer waiting time is required, reducing the production efficiency of the riser assembly. Therefore, the curing time of the phenolic resin sand is 1 min - 60 min. For example, it can be 1 min, 15 min, 30 min, 45 min, 60 min. In this embodiment, 30 min is preferably selected.

[0042] In order to enable an appropriate amount of phenolic resin sand to be accommodated between the outer wall of the heat-insulating plate 5 and the inner wall of the riser 3, neither wasting the phenolic resin sand nor the heat-insulating filler 6 formed by the phenolic resin sand having a good heat-insulating effect, the width of the gap between the outer wall of the heat-insulating plate 5 and the inner wall of the riser 3 is between 10 mm - 15 mm. For example, it can be 10 mm, 12.5 mm, 15 mm. In this embodiment, since the heat-insulating plate 5 is frustum-shaped, the width of the gap between the outer wall of the heat-insulating plate 5 and the inner wall of the riser 3 gradually increases from bottom to top, but the width at each place should be within the range of 10 mm - 15 mm.

[0043] In addition, as Figure 1 、 2 shown, in order to reduce the riser volume ratio, the inner cavity 2 gradually narrows along the direction from the outside to the inner cavity 2. Thereby, it is beneficial to improve the utilization rate of molten steel.

[0044] The implementation principle of the mold for the die-casting process of this application is as follows: First, place the insulation board 5 on the step 4 so that the upper side of the insulation board 5 is aligned with the upper side opening of the riser 3. Then fill the gap between the outer wall of the insulation board 5 and the inner wall of the outer shell 7 with phenolic resin sand and ram it to form a ramming material. Let it stand still until the ramming material cures to form a heat-insulating filling body 6. Finally, blow the inner cavity 2 with an air duct to clean the inner cavity 2 so that there is no phenolic resin sand attached.

[0045] Compared with the existing heat preservation technology of the riser 3, for the mold for the die-casting process of this application, the insulation board 5 is integrally placed on the step 4, and a heat-insulating filling body 6 formed by ramming and curing phenolic resin sand is filled between the outer wall of the insulation board 5 and the inner wall of the outer shell 7. The structure is simple and the installation is convenient. Moreover, due to the support of the heat-insulating filling body 6, the insulation board 5 is not easily deformed during use, and thus is not easily loosened to generate ingot gaps during the casting process, will not cause floating plates and drilling steel, has a good heat preservation effect, and effectively ensures the heat preservation conditions at the head of the ingot.

[0046] On the other hand, since the mold for the die-casting process of this application is simple to install, the safety risks caused by high altitude and high temperature that the staff need to bear are less. It can not only improve production efficiency, but also be beneficial to personal safety, and can also reduce the damage of the insulation board 5 during installation.

[0047] The above embodiments only illustratively explain the principles and effects of the present invention, rather than limiting the present invention. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes completed by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A mold for a die casting process, characterized in that: It comprises a mold body (1) and a riser assembly; wherein: An inner cavity (2) is formed inside the mold body (1); The riser assembly comprises a shell (7), a heat insulating plate (5) and a heat insulating filling body (6); The shell (7) is a hollow structure, the lower end of which is fixedly connected to the upper side of the mold body (1), and the upper end of which is open; At the connection between the outer shell (7) and the inner cavity (2), a step (4) is formed around the inner wall of the inner cavity (2); the step surface of the step (4) faces upward; The insulation plate (5) is an integrally formed cylindrical structure; the lower edge of the insulation plate (5) is in contact with the step (4); the insulation plate (5) is surrounded by a riser (3); the riser (3) is connected from top to bottom; the lower opening of the riser (3) is connected to the inner cavity (2), and the upper opening is connected to the outside, so that the molten steel for shrinkage compensation flows into the inner cavity (2) through the riser (3); The heat-insulating filler (6) is filled between the inner wall of the outer shell (7) and the outer wall of the heat-insulating board (5), and is a block structure formed by solidifying phenolic resin sand.

2. The mold for die casting process according to claim 1, characterized in that: The fineness of the phenolic resin sand is 50 meshes to 100 meshes.

3. The mold for die casting process according to claim 1, characterized in that: The curing time of the phenolic resin sand is 1 min-60 min.

4. The mold for die casting process according to claim 1, characterized in that: The inner cavity (2) gradually narrows along the direction from the outside to the inner cavity (2).

5. The mold for die casting process according to claim 1, characterized in that: The width of the gap between the outer wall of the insulation board (5) and the inner wall of the outer shell (7) is between 10 mm and 15 mm.

6. The mold for die casting process according to claim 1, characterized in that: The side of the heat insulation plate (5) away from the step (4) is flush with the edge of the opening of the outer shell (7) away from the inner cavity (2).

7. The mold for die casting process according to claim 1, characterized in that: The width of the step (4) is between 15 mm and 30 mm.

8. The mold for die casting process according to claim 1, characterized in that: The wall thickness of the thermal insulation board (5) is 30 mm-100 mm.

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