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(11) | EP 4 212 263 A1 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | CARBON-FREE ENVIRONMENT-FRIENDLY SAND CASTING PROCESS |
FIELD
[0001] The invention relates to the technical field of casting, and more specifically, to a carbon-free environment-friendly wet sand casting process.
BACKGROUND
[0002] In today's industrial production, some products will be used in the form of casting, so that it is necessary to make the casting mold for operation.
[0003] However, in the existing casting process, a large amount of pollution gas will be generated in the process flow, which is not beneficial to environmental protection, and with the current state advocated dual-carbon mode, it is required that the casting process be improved. At the same time, in the existing process flow, the raw materials and treatment methods used are not conducive to control, and the precision and effect of casting production would be affected, so a new environment-friendly process needs to be proposed.
SUMMARY
[0004] The purpose of the present invention is to provide a carbon-free and environmentally friendly wet sand casting method in order to solve the disadvantages of the prior art.
[0006] A carbon-free environment-friendly wet sand casting method is provided. The method includes the steps as follows.
[0007] S1: selecting raw materials: selecting water-washed sand as basic raw material, and selecting clay as auxiliary raw material;
[0008] S2. raw material treatment: filtering the washed sand, crushing and screening the clay to form a treated raw material;
[0009] S3, mixing: the treated raw materials are put into the mixer in proportion, uniformly stirred for 60 seconds to 80 seconds, then water is added, and further stirred for 30 seconds to 45 seconds to form mixed raw materials;
[0010] S4. modeling: taking out the mixed raw materials from the mixer and putting them into a mold for molding to form a casting sand mold.
[0011] S5, molten iron smelting: putting iron raw materials into a smelting furnace, heating and smelting to form molten iron;
[0012] S6. molten iron heat preservation: the molten iron is continuously heated to 30 °C to 50 °C for 10 minutes to 15 minutes to obtain heat-insulating molten iron;
[0013] S7. casting: pouring the heat-insulating molten iron out of the furnace into the casting sand mold, controlling the casting time and pressure to form the casting mold;
[0015] S9. demoulding: separate the sand mold, separate the product, conduct cleaning, and complete demoulding.
[0016] Preferably, the silica content of the washed sand in S1 is 92% -95%, and the sand is of the same kind.
[0017] Preferably, the clay in S2 is filtered and screened using a 200 mesh screen, and mechanically vibrated and screened at a screening rate of 20 kg / min to 25 kg / min.
[0018] Preferably, the proportion in said S3 comprises water washed sand 92% -96%, clay 2% -4% and water 3% -5%.
[0019] Preferably, taking out the mixed raw materials from the mixer in the S4 further comprises hermetically storing the mixed raw materials at a room temperature and a humidity of 60% -75%.
[0020] Preferably, the molten iron smelting in S5 comprises the following steps:
A1, pig iron, carburizing agent, steel scrap and return material are sequentially added into the smelting furnace, the electric heating power is 2000KW to 2300KW, and the melting temperature is 1400 °C to 1450 °C;
A2, after smelting, de-energize the slag, sample and detect the carbon and alloy composition;
A3. heat the auxiliary material to 1500 °C to 1530 °C, and leave it to stand for 30 minutes to 35 minutes;
A4. weigh the inoculant, key it into the ladle, deslagging the inoculant, and then the molten iron melting can be finished.
[0021] Preferably, the insulation temperature in S6 is 1560 °C to 1580 °C, and the exit temperature in S7 is the insulation temperature.
[0022] Preferably, the pouring time in the S7 is 15 seconds to 20 seconds, the pouring pressure is 1.2 MPa to 1.35 MP, and the temperature and pressure are kept for 5 seconds to 8 seconds.
[0023] Preferably, the cooling setting in the S8 is air-cooled, and the air is continuously blown for 30 minutes to 60 minutes.
[0024] In the carbon-free environment-friendly wet sand casting process provided by the invention, the washed sand with high silica content is used as the raw material, the cost is low, the carbon emission of the production raw material is greatly reduced, the energy is saved and the environment is protected, In combination with the specially treated clay as the mixed raw material, the mixture can be mixed after adding water, the sand mold can be made conveniently after operation, the use of casting can be facilitated, and the temperature of molten iron can be controlled through smelting and heat preservation. To ensure the efficiency and quality of pouring and forming, facilitate the control operation, facilitate the shaping and demoulding, greatly improve the convenience and fineness of the process flow, ensure the effect of energy saving and environmental protection, and facilitate the popularization and use.
DETAILED DESCRIPTION
[0025] In order to make the objects, technical schemes and advantages of the present invention more clearly understood, the present invention will be described in further detail with reference to specific embodiments. It should be understood that the specific embodiments described herein are only for explaining the present invention and are not intended to limit the present invention.
[0026] A carbon-free environment-friendly wet sand casting process comprises the following steps:
S1: selecting raw materials: the water-washed sand is selected as a basic raw material, and the clay is selected as an auxiliary raw material;
S2. treating raw material treatment: the washed sand is filtered, and the clay is crushed and screened to form a treated raw material;
S3, mixing: the treated raw materials are put into the mixer in proportion, uniformly stirred for 60 seconds to 80 seconds, then water is added, and further stirred for 30 seconds to 45 seconds to form mixed raw materials;
S4. modeling: taking out the mixed raw materials from the mixer and putting them into a mold for molding to form a casting sand mold.
S5, molten iron smelting: putting iron raw materials into a smelting furnace, heating and smelting to form molten iron;
S6. molten iron heat preservation: the molten iron is continuously heated to 30 °C to 50 °C for 10 minutes to 15 minutes to obtain heat-insulating molten iron;
S7. casting: pouring the heat-insulating molten iron out of the furnace into the casting sand mold, controlling the casting time and pressure to form the casting mold;
S8. shaping: Cooling and shaping the casting mold to form the shaping mold;
S9. demoulding: separateing the sand mold with the product, conduct cleaning, and complete demoulding.
[0027] Preferably, the silica content of the washed sand in S1 is 92% -95%, and the sand is of the same kind.
[0028] Preferably, the clay in S2 is filtered and screened using a 200 mesh screen, and mechanically vibrated and screened at a screening rate of 20 kg/ min to 25 kg/ min.
[0029] Preferably, the proportion in said S3 comprises water washed sand 92% -96%, clay 2% -4% and water 3% -5%.
[0030] Preferably, taking out the mixed raw materials from the mixer in the S4 further includes hermetically storing the mixed raw materials at a room temperature and a humidity of 60% -75%.
[0031] Preferably, the molten iron smelting in S5 includes the following steps:
A1, pig iron, carburizing agent, steel scrap and return material are sequentially added into the smelting furnace, the electric heating power is 2000KW to 2300KW, and the melting temperature is 1400 °C to 1450 °C;
A2, after smelting, de-energizing the slag, sampling and detecting the carbon and alloy composition;
A3. heating the auxiliary material to 1500 °C to 1530 °C, and leave it to stand for 30 minutes to 35 minutes;
A4. weighing the inoculant, keying it into the ladle, deslagging the inoculant, and then the molten iron melting can be finished.
[0032] Preferably, the insulation temperature in S6 is 1560 °C to 1580 °C, and the exit temperature in S7 is the insulation temperature.
[0033] Preferably, the pouring time in the S7 is 15 seconds to 20 seconds, the pouring pressure is 1.2 MPa to 1.35 MP, and the temperature and pressure are kept for 5 seconds to 8 seconds.
[0034] Preferably, the cooling setting in the S8 is air-cooled, and the air is continuously blown for 30 minutes to 60 minutes.
[0035] In the carbon-free environment-friendly wet sand casing method. The water-washed sand with a high silica content is used as a raw material, the cost is low and easy to obtain, the carbon emission of the production raw material is greatly reduced. In combination with that specially treat pottery clay as a mixed raw material, the mixture material is formed by mix after adding water, the sand mold is made conveniently aft operation, and the casting is used, the efficiency and quality of pouring and molding is ensured, effectively control and operation, facilitate molding and demoulding, greatly improve the convenience and fineness of the process flow, ensure the energy-saving and environmental protection effect, and facilitate popularization and use.
S1: selecting raw materials: water-washed sand is selected as a basic raw material, and a clay is selected as an auxiliary raw material;
S2. raw material treating: filtering the water-washed sand, crushing and screening the clay to form a treated raw material;
S3, mixing: the treated raw materials are put into the mixer in proportion, uniformly stirred for 60 seconds to 80 seconds, adding water, and further stirring for 30 seconds to 45 seconds to form mixed raw materials;
S4. modeling: taking out the mixed raw materials from the mixer and putting them into a mold for molding to form a casting sand mold;
S5, molten iron smelting: putting iron raw materials into a smelting furnace, heating and smelting to form molten iron;
S6. molten iron heat preservation: the molten iron is continuously heated to 30 °C to 50 °C for 10 minutes to 15 minutes to obtain heat-insulating molten iron;
S7. casting: pouring the heat-insulating molten iron out of the furnace into the casting sand mold, controlling the casting time and pressure to form the casting mold;
S8. shaping: cooling and shaping the casting mold to form the shaping mold; and
S9. demoulding: separating the sand mold and the product, cleaning, and completing demoulding.
water-washed sand 92% -96%,
clay 2% -4%; and
water 3% -5%.
A1, adding pig iron, carburizing agent, steel scrap and return material into the smelting furnace, the electric heating power is 2000KW to 2300KW, and the melting temperature is 1400 °C to 1450 °C;
A2, after smelting, de-energize the slag, sample and detect the carbon and alloy composition;
A3. heating the auxiliary material to 1500 °C to 1530 °C, and leave it to stand for 30 minutes to 35 minutes;
A4. weighing the inoculant, keying it into the ladle, deslagging the inoculant, and then the molten iron melting can be finished.