Compound die ingot casting die for producing die casting steel ingot and casting method

Abstract

The invention discloses a compound die ingot casting die for producing a die casting steel ingot and a casting method, and belongs to the technical field of design and manufacturing of die casting production process equipment. According to the compound die ingot casting die for producing the die casting steel ingot and the casting method, the internal quality of a casting blank can be effectively improved, and the quality defects such as internal segregation, looseness and shrinkage cavities are reduced or even eradicated. The composite die ingot mold comprises a die ingot mold body and a steel ingot cooling system, and molten steel poured into the die ingot mold body is condensed and cooled to a specified temperature range according to a specified cooling gradient, a specified cooling speed and a specified cooling strength sequence under the control of the steel ingot cooling system. According to the casting method, the water flow temperature and flow rate of each layer of pipeline are set firstly, then molten steel is injected into a cast ingot mold body, a cooling system is started, and the molten steel is cooled into a cast ingot according to the specified cooling gradient, the specified cooling speed and the specified cooling strength in the process of forming a casting blank along with solidification of the molten steel.

Description

Technical Field

[0001] The present invention relates to a composite ingot mold, in particular to a composite ingot mold for producing cast steel ingots, belonging to the technical field of design and manufacture of casting production process equipment. The present invention also relates to a casting method for producing cast steel ingots using the composite ingot mold for producing cast steel ingots. Background Art

[0002] The iron and steel industry is an important pillar industry of the national economy. As a key intermediate product in iron and steel production, the quality of steel ingots directly affects the performance of subsequent processes such as rolling and forging. With the development of high-end manufacturing, the requirements for the internal structure uniformity, density, and defect control of steel ingots are getting higher and higher.

[0003] In the traditional production process of cast steel ingots, after the molten steel is poured into the ingot mold and cools with the mold, due to uneven cooling, defects such as segregation, porosity, and shrinkage cavities are likely to occur inside the steel ingot. These defects will seriously affect the quality and subsequent processing performance of the steel ingot. When the size of the steel ingot increases, the defects caused by this process are more serious. The existing cooling methods usually adopt a single cooling method, such as cooling with the mold or direct water spraying cooling, etc., and cannot effectively control the temperature gradient inside the steel ingot, making it difficult to achieve sequential solidification. Summary of the Invention

[0004] The technical problem to be solved by the present invention is: to provide a composite ingot mold for producing cast steel ingots that can effectively improve the internal quality of the cast billet and reduce or even eliminate quality defects such as internal segregation, porosity, and shrinkage cavities. The present application also provides a casting method for producing cast steel ingots using the composite ingot mold for producing cast steel ingots.

[0005] The technical solution adopted to solve the above technical problem is: a composite ingot mold for producing cast steel ingots, including a cast ingot mold body. The composite ingot mold further includes a steel ingot cooling and temperature reduction system. The molten steel poured into the cast ingot mold body is sequentially cooled and reduced in temperature to a specified temperature range under the control of the steel ingot cooling and temperature reduction system according to a specified temperature reduction gradient, a specified temperature reduction speed, and a specified temperature reduction intensity.

[0006] Furthermore, the cast ingot mold body is made of steel material, and the cooling ends of the steel ingot cooling and temperature reduction system are sequentially coated on the outer side wall of the cast ingot mold body made of steel material according to a specified position.

[0007] The preferred embodiment of the above solution is that the steel ingot cooling and temperature reduction system consists of a set of water-cooling and temperature reduction systems, and the water-cooling and temperature reduction ends of the water-cooling and temperature reduction systems are sequentially coated on the outer side wall of the cast ingot mold body according to a specified position.

[0008] Furthermore, the water-cooling cooling end includes at least three groups of water-cooling cooling sub-ends with gradually decreasing cooling speed and cooling intensity. Each group of water-cooling cooling sub-ends is arranged on the outer side wall of the ingot casting mold body in the order of gradually decreasing cooling intensity and gradually decreasing cooling speed from bottom to top along the ingot casting mold.

[0009] The preferred way of the above solution is that each group of water-cooling cooling sub-ends is composed of water-cooling coils coated on the corresponding outer side wall of the ingot casting mold body. The cooling intensity and decreasing speed of each group of water-cooling coils are determined by controlling the temperature and flow rate of the cooling water input into the corresponding water-cooling coils.

[0010] Furthermore, there are eight water-cooling coils arranged in sequence from the molten steel injection end to the output end of the cast steel ingot. The flow rates of the cooling water flowing in each group of water-cooling coils from far to near are 8L / min, 7L / min, 6L / min, 5L / min, 4L / min, 3L / min, 2L / min, and 1L / min respectively; the water temperatures of the cooling water flowing in each group of water-cooling coils from far to near are 20°C, 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, and 90°C respectively.

[0011] The preferred way of the above solution is that the water-cooling cooling system further includes at least a water tank, a water pump, a temperature controller, and a flow controller. Each group of water-cooling coils is connected to the corresponding water tank through the corresponding water pump. The water temperature and flow rate of the cooling water flowing in each group of water-cooling coils are controlled by a set of temperature controller and a set of flow controller respectively.

[0012] Furthermore, there is at least a coil spacing between each group of water-cooling coils.

[0013] Using the above composite ingot casting mold for producing cast steel ingots to produce cast steel ingots, the casting method first sets the water flow temperature and flow rate of each layer of pipeline according to the size and material of the steel ingot, and then injects the qualified molten steel from the opening at the top of the ingot casting mold body into the ingot casting mold body and starts to input cooling water into each layer of pipeline for cooling. As the molten steel solidifies to form a billet and along the moving direction of the billet, the billet is cooled and condensed to a specified temperature at a specified cooling gradient, a specified cooling speed, and a specified cooling intensity to complete the production of the cast steel ingot.

[0014] The beneficial effects of the present invention are as follows: The technical solution provided by this application is based on the existing die-casting ingot mold body. By adding a steel ingot cooling and temperature reduction system, a composite die-casting ingot mold of this application is formed. Then, the molten steel poured into the die-casting ingot mold body is cooled and reduced in temperature in sequence according to the specified temperature reduction gradient, specified temperature reduction speed, and specified temperature reduction intensity under the control of the steel ingot cooling and temperature reduction system to the specified temperature range. In this way, since the entire cooling process of the die-cast steel ingot can be well controlled from the time when the molten steel enters the mold to the time when the ingot is taken out of the mold, the internal quality problems that occur during the free cooling or spray cooling of the die-cast steel ingot in the prior art due to the inability to control its cooling process are solved. After adopting the above technical solution of this application, since the cooling process of the die-cast steel ingot can be better controlled, the internal quality of the cast billet can be effectively improved, and the purpose of reducing or even eliminating quality defects such as segregation, porosity, and shrinkage cavities inside it can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a simplified structural sectional view of the composite die-casting ingot mold for producing die-cast steel ingots of the present invention.

[0016] The marks in the figure are: die-casting ingot mold body 1, water-cooled temperature reduction sub-end 2, die-cast steel ingot 3. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0017] As Figure 1Shown is a composite ingot mold for producing ingot steel by mold casting, which can effectively improve the internal quality of the cast billet and reduce or even eliminate quality defects such as internal segregation, porosity, and shrinkage cavity. The composite ingot mold includes an ingot mold body 1, and the composite ingot mold also includes an ingot cooling and temperature reduction system. The molten steel poured into the ingot mold body 1 is cooled and reduced in temperature in sequence according to a specified temperature reduction gradient, a specified temperature reduction speed, and a specified temperature reduction intensity under the control of the ingot cooling and temperature reduction system to a specified temperature range. The technical solution provided in this application is based on the existing ingot mold body, and the composite ingot mold of this application is formed by adding an ingot cooling and temperature reduction system. Then, the molten steel poured into the ingot mold body is cooled and reduced in temperature in sequence according to a specified temperature reduction gradient, a specified temperature reduction speed, and a specified temperature reduction intensity under the control of the ingot cooling and temperature reduction system to a specified temperature range. In this way, since the entire cooling process of the ingot steel can be well controlled from the time when the molten steel enters the mold to the time when the ingot is taken out of the mold, the internal quality problems that occur during the free cooling or spray cooling of the ingot steel in the prior art due to the inability to control its cooling process are solved. After adopting the above technical solution of this application, since the cooling process of the ingot steel can be better controlled, the internal quality of the cast billet can be effectively improved, and the purpose of reducing or even eliminating quality defects such as segregation, porosity, and shrinkage cavity in its interior can be achieved. Combining with the situation of the prior art, in order to improve the temperature reduction control effect of the ingot steel by mold casting, the ingot mold body 1 of this application is made of steel material, and the cooling ends of the ingot cooling and temperature reduction system are covered on the outer side wall of the ingot mold body 1 made of steel material in a specified position sequence.

[0018] Correspondingly, as a key component of the improvement of this application, in order to simplify its structure, facilitate the adoption of general equipment in the prior art, reduce the use of special parts, reduce costs and facilitate manufacturing, while maximizing the control of the cooling of the ingot casting 3, the ingot cooling and temperature reduction system of this application is composed of a set of water-cooling temperature reduction systems. The water-cooling temperature reduction ends of the water-cooling temperature reduction system are coated on the outer side wall of the ingot casting mold body in the specified position sequence. At this time, the water-cooling temperature reduction end includes at least three groups of water-cooling temperature reduction sub-ends 2 with gradually decreasing cooling speed and cooling intensity. Each group of water-cooling temperature reduction sub-ends 2 is arranged on the outer side wall of the ingot casting mold body 1 in the order of gradually weakening cooling intensity and gradually decreasing cooling speed from bottom to top along the ingot casting mold and from far to near along the output direction of the ingot casting 3. A more specific structure is that each group of water-cooling temperature reduction sub-ends 2 is composed of water-cooling coils coated on the corresponding outer side wall of the ingot casting mold body 1. The cooling intensity and reduction speed of each group of water-cooling coils are determined by controlling the temperature and flow rate of the cooling water input into the corresponding water-cooling coils. The preferred method is that there are eight water-cooling coils arranged in sequence from the molten steel injection end to the output end of the ingot casting 3. When specifically arranged, there is at least a distance of one coil between each group of water-cooling coils; when controlling the cooling temperature of the ingot casting 3, the flow rates of the cooling water flowing in each group of water-cooling coils from far to near are 8L / min, 7L / min, 6L / min, 5L / min, 4L / min, 3L / min, 2L / min and 1L / min respectively; the water temperatures of the cooling water flowing in each group of water-cooling coils from far to near are 20°C, 30°C, 40°C, 50°C, 60°C, 70°C, 80°C and 90°C respectively.

[0019] At the same time, in order to facilitate the control of the water temperature of each water-cooling coil, the water-cooling temperature reduction system of this application also includes at least a water tank, a water pump, a temperature controller and a flow controller. Each group of water-cooling coils is connected to the corresponding water tank through the corresponding water pump. The water temperature and flow rate of the cooling and temperature reduction water flowing in each group of water-cooling coils are respectively controlled by a set of temperature controller and a set of flow controller.

[0020] So far, a casting method for producing an ingot casting using the composite ingot casting mold for producing an ingot casting provided in this application can be controlled according to the following steps: first, set the water flow temperature and flow rate of each layer of pipeline according to the size and material of the ingot, and then inject the qualified molten steel into the ingot casting mold body from the opening at the top of the ingot casting mold body and start to input cooling water into each layer of pipeline for cooling. As the molten steel solidifies to form a billet, the billet is cooled and the temperature is reduced to the specified temperature according to the specified cooling gradient, specified cooling speed and specified cooling intensity along the moving direction of the billet to complete the production of the ingot casting.

[0021] In summary, the technical solution provided in this application also has the following advantages

[0022] 1. By controlling the cooling intensity of the ingot from bottom to top, sequential solidification is achieved, significantly reducing defects such as segregation, porosity, and shrinkage cavities, and improving the internal quality of the ingot. Reducing defects means lowering the scrap rate and subsequent processing costs. At the same time, optimizing the cooling process can shorten the production cycle and improve production efficiency.

[0023] 2. The technical solution of this application is applicable to the production of ingots of different sizes and materials, with strong versatility and scalability. By precisely controlling the cooling water flow rate and temperature, waste of water resources and energy is reduced, which conforms to the concept of sustainable development.

[0024] 3. By optimizing the cooling process, the quality of the ingot can be significantly improved to meet the market demand for high-end steel. In addition to the steel industry, for large castings in the foundry industry (such as wind power castings, ship castings, etc.), there are also problems with defects caused by uneven cooling. The technology of this application can be extended to other metal casting fields and has broad application potential. With the improvement of environmental protection requirements, the steel and foundry industries need more energy-saving and efficient production technologies.

[0025] 4. In terms of uniform solidification structure, by controlling the cooling intensity of the ingot from bottom to top, sequential solidification is achieved to obtain a uniform solidification structure.

[0026] 5. In terms of defect reduction, defects such as segregation, porosity, and shrinkage cavities inside the ingot are effectively reduced, improving the quality of the ingot.

[0027] 6. In terms of improving production efficiency, by optimizing the cooling process, the solidification time of the ingot is shortened, improving production efficiency.

[0028] The technical solution of this application is further described below through specific embodiments:

[0029] The purpose of this application is to provide an external water-cooling pipeline system for die-cast ingots. By designing a water-cooling pipeline outside the ingot mold and introducing water flows with different flow rates and temperatures layer by layer from bottom to top, the cooling intensity of the ingot from bottom to top is controlled, sequential solidification is achieved, a uniform solidification structure is obtained, and defects such as segregation, porosity, and shrinkage cavities are reduced.

[0030] Technical solution:

[0031] 1. Design of the water-cooling pipeline system:

[0032] 1) Design multiple layers of water-cooling pipelines on the outer wall of the ingot mold. Each layer of the pipeline is independently controlled and can introduce water flows with different flow rates and temperatures.

[0033] 2) The water-cooling pipeline is divided into several layers from bottom to top, and the water flow rate and temperature of each layer of the pipeline can be adjusted according to needs.

[0034] 2. Control of cooling intensity:

[0035] 1) The lower pipeline admits water flow with a relatively low temperature and a relatively large flow rate to enhance the cooling intensity at the lower part.

[0036] 2) The upper pipeline admits water flow with a relatively high temperature and a relatively small flow rate to weaken the cooling intensity at the upper part.

[0037] 3) By adjusting the water flow rate and temperature of each layer of pipeline, the temperature gradient control of the ingot from bottom to top is achieved.

[0038] 3. Realization of progressive solidification:

[0039] 1) After the molten steel is poured into the ingot mold, the lower part is first rapidly cooled and starts to solidify.

[0040] 2) As the cooling intensity gradually weakens, the molten steel in the upper part gradually solidifies, thus realizing progressive solidification from bottom to top.

[0041] 3) By controlling the cooling intensity, a uniform temperature gradient is formed inside the ingot, reducing defects such as segregation, porosity, and shrinkage cavities.

[0042] Example 1

[0043] 1. Arrangement of water-cooling pipelines:

[0044] 1) Multiple layers of annular water-cooling pipelines are welded on the outer wall of the ingot mold, and each layer of pipeline is independent.

[0045] 2) Each layer of pipeline is provided with an independent water inlet and an independent water outlet, which is convenient for adjusting the water flow rate and temperature.

[0046] 2. Cooling water supply system:

[0047] 1) A cooling water supply system is set up, including a water pump, a water tank, a temperature controller, and a flow controller.

[0048] 2) Through the temperature controller and the flow controller, the water flow temperature and flow rate of each layer of pipeline are adjusted respectively.

[0049] 3. Operating steps:

[0050] 1) Before pouring the molten steel, set the water flow temperature and flow rate of each layer of pipeline according to the size and material of the ingot.

[0051] 2) After the molten steel is poured into the ingot mold, start the cooling water supply system to start cooling.

[0052] 3) According to the solidification situation of the ingot, adjust the water flow temperature and flow rate of each layer of pipeline in real time to ensure progressive solidification of the ingot from bottom to top.

Claims

1. A composite ingot mold for producing a die-cast steel ingot, comprising a die-cast ingot mold body (1), characterized in that: The composite ingot casting mold also includes an ingot cooling system. The molten steel poured into the ingot casting mold body (1) is condensed and cooled to a specified temperature range in a specified cooling gradient, a specified cooling speed and a specified cooling intensity sequence under the control of the ingot cooling system.

2. The composite mold for producing mold-cast steel ingots according to claim 1, characterized in that: The die casting ingot mold body (1) is made of steel material, and the cooling end of the steel ingot cooling system is coated on the outer side wall of the die casting ingot mold body (1) made of steel material in a prescribed position sequence.

3. The composite mold for producing mold-cast steel ingots according to claim 1 or 2, characterized in that: The steel ingot cooling system is composed of a water cooling system, and the water cooling end of the water cooling system is coated on the outer side wall of the mold casting ingot mold body according to a specified position sequence.

4. The composite mold for producing mold-cast steel ingots according to claim 3, characterized in that: The water-cooling cooling end comprises at least three groups of water-cooling cooling sub-ends (2) whose cooling speed and cooling strength decrease in sequence. Each group of water-cooling cooling sub-ends (2) is arranged on the outer wall of the mold casting mold body (1) from bottom to top along the output direction of the mold casting steel ingot (3) from far to near in the sequence of gradually weakening cooling strength and gradually reducing cooling speed.

5. The composite mold for producing mold-cast steel ingots according to claim 4, characterized in that: Each group of water-cooling sub-ends (2) is composed of water-cooling coils coated on the corresponding outer side walls of the mold casting ingot mold body (1), and the cooling intensity and cooling speed of each group of water-cooling coils are determined by controlling the temperature and flow rate of cooling water input into the corresponding water-cooling coils.

6. The composite mold for producing mold-cast steel ingots according to claim 5, characterized in that: There are eight water-cooling coils arranged in sequence from the molten steel injection end to the output end of the mold-cast steel ingot (3), and the flow rates of cooling water running in each group of water-cooling coils from far to near are 8L / min, 7L / min, 6L / min, 5L / min, 4L / min, 3L / min, 2L / min and 1L / min respectively; the temperatures of cooling water running in each group of water-cooling coils from far to near are 20°C, 30°C, 40°C, 50°C, 60°C, 70°C, 80°C and 90°C respectively.

7. The composite mold for producing mold-cast steel ingots according to claim 6, characterized in that: The water cooling system also includes at least a water tank, a water pump, a temperature controller and a flow controller. Each group of water cooling coils is connected to the corresponding water tank through a corresponding water pump. The water temperature and flow rate of the cooling water running in each group of water cooling coils are controlled by a set of temperature controllers and a set of flow controllers respectively.

8. The composite mold for producing mold-cast steel ingots according to claim 7, characterized in that: Each group of water cooling coils is spaced apart from each other by at least the spacing of one coil.

9. A casting method for producing a die-cast steel ingot using the composite ingot casting mold for producing a die-cast steel ingot as claimed in claim 8, characterized in that: The casting method first sets the water flow temperature and flow rate of each layer of pipeline according to the size and material of the steel ingot, then injects qualified molten steel into the mold casting mold from the opening at the top of the mold casting mold body and starts the cooling water input of each layer of pipeline for cooling. As the molten steel solidifies to form a cast billet and moves in the direction of the cast billet, the cast billet is condensed and cooled to a specified temperature according to a specified cooling gradient, a specified cooling speed and a specified cooling intensity to complete the production of the mold casting steel ingot.

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