Wind generating set shell with high heat dissipation effect and casting method thereof

Abstract

The invention discloses a casting method of a wind generating set shell with a high heat dissipation effect, and relates to the technical field of wind power generation. The method comprises the steps of material preparation and pretreatment; 2, manufacturing and processing a mold; 3, smelting and pouring; 4, forming and cooling; 5, subsequent heat treatment; the smelting and pouring process comprises the following steps: 1, metal smelting; 2, purification treatment; 3, preheating the mold; 4, vacuumizing and mold filling; and 5, boosting and maintaining the pressure. Molten aluminum alloy liquid is pressed into a mold cavity for casting through the pressure difference, the solidification process of a casting is more uniform and stable by controlling the low pressure, the cooling rate is greatly reduced, refining of the internal microstructure of the material is achieved, and then the high-performance shell material is obtained. The fine grain structure formed by rapid solidification is beneficial to improving the heat conduction performance and the mechanical performance of the material, so that the heat dissipation capability of the shell is improved, and the shell of the wind generating set can dissipate heat more effectively in the using process.

Description

Technical Field

[0001] The invention relates to the technical field of wind power generation, in particular to a wind power generator housing with high heat dissipation effect and a casting method thereof. Background Art

[0002] The wind turbine casing, also known as the wind turbine nacelle or wind turbine nacelle, is an important component of a large wind turbine. It covers and protects the equipment and electrical components inside the wind turbine. It is installed on the top of the tower at high altitude. Its main function is to protect the internal equipment from external environmental factors to ensure the smooth operation of the wind turbine. The wind turbine nacelle has the characteristics of high specific strength, aging resistance, beautiful appearance and light weight.

[0003] The defects of the generator housing in the prior art are: 1. Patent document US20200161931A1 discloses a low-noise generator casing. The grain structure of the generator casing is not refined enough during the casting process, and the uneven solidification process of the casting can easily lead to segregation and shrinkage defects. The wind turbine casing cannot effectively dissipate heat during use.

[0004] 2. Patent document CN211089282U discloses a wind turbine casing. The grain structure of the casing is not refined enough during the casting process, and the solidification process of the casting is uneven, which easily leads to segregation and shrinkage defects. The wind turbine casing cannot effectively dissipate heat during use.

[0005] 3. Patent document CN102857009B discloses a generator casing for a wind turbine. The generator casing is not subjected to high-frequency quenching heat treatment during the casting process, resulting in a shallow hardening layer. The thermal stress and structural stress of the material during the heating process will increase the risk of deformation and cracking of the casing after molding, resulting in poor thermal conductivity and thermal stability of the casing.

[0006] 4. Patent document CN116950859B discloses a unit casing with intelligent heat dissipation based on wind power generation. The generator casing is not subjected to high-frequency quenching heat treatment during the casting process, resulting in a shallow hardening layer. The thermal stress and structural stress of the material during the heating process will increase the risk of deformation and cracking of the casing after molding, resulting in poor thermal conductivity and thermal stability of the casing. Summary of the invention

[0007] The object of the present invention is to provide a wind turbine generator housing with high heat dissipation effect and a casting method thereof, so as to solve the problems raised in the above background technology.

[0008] To achieve the above object, the present invention provides the following technical solution: a casting method for a wind turbine housing with high heat dissipation effect, characterized in that it comprises the following steps: 1. material preparation and pretreatment; 2. mold manufacturing and processing; 3. smelting and pouring; 4. molding and cooling; 5. subsequent heat treatment; The smelting and pouring process includes the following steps: 1. metal smelting; 2. purification treatment; 3. mold preheating; 4. vacuuming and filling; 5. pressure increasing and pressure maintaining; Preferably, the material preparation and pretreatment steps are as follows: soaking the aluminum alloy block in 36% hydrochloric acid, the hydrochloric acid softens the rust on the aluminum alloy plate and causes it to fall off, and after the rust removal treatment, spraying an aluminum alloy cleaning agent on the surface of the aluminum alloy and wiping it with a soft cloth to remove various oil stains, oxide layers, metal powders and stains on the surface of the aluminum alloy.

[0009] Preferably, the mold manufacturing and processing steps are as follows: according to the shape and specification drawings of the wind turbine casing, a reasonable mold structure is designed to ensure that the mold is easy to disassemble and clean, the mold shrinkage rate is controlled at 1% to 3%, and the mold is cleaned and lubricated with graphite lubricant.

[0010] Preferably, the smelting and pouring steps are as follows: Step 1 Metal smelting: Place the aluminum alloy block in a vacuum smelting furnace, close the furnace door and seal it, use a vacuum pump to draw out the gas inside the vacuum smelting furnace, and evacuate for 30 seconds. Turn on the vacuum smelting furnace, raise the temperature in the furnace to the hot melting temperature of the aluminum alloy, control the temperature at 700°C to 740°C, and smelting for 10min to 20min to avoid excessive oxidation of the molten metal or the generation of other impurities; Step 2 Purification: During the vacuum smelting process, introduce an appropriate amount of argon gas to prevent oxidation of the molten metal surface and remove dissolved gases in the molten metal; Step 3 Mold preheating: Place the mold in a preheating furnace, heat the mold through the high temperature environment in the furnace, and maintain the heating temperature at 100°C to 250°C to ensure that the mold is heated to the required temperature and remains stable. After heating, take the mold out of the preheating furnace. And quickly install it to the pouring position; Step 4: Vacuuming and filling: After ensuring that the metal is completely melted, adjust the heat source power of the vacuum melting furnace to adjust the pouring temperature. The pouring temperature is maintained at 680℃~750℃. Use a vacuum pump to vacuum the casting mold to remove air and impurities therein. After reaching the required vacuum degree, enter the filling stage, control the pressure difference between the upper and lower pressure tanks so that the molten metal flows smoothly into the mold cavity under the action of the pressure difference, keep the pressure of the upper tank unchanged, and increase the pressure of the lower tank steadily to form a sufficient pressure difference so that the molten aluminum alloy metal liquid fills the cavity; Step 5: Boosting and maintaining pressure: After the metal filling is completed, pressurize the upper and lower pressure tanks at the same time to quickly raise the pressure to 350kPa to ensure that the metal completely fills every corner of the mold. After boosting, keep it at 400kPa for 15~20s so that the metal is fully solidified in the mold.

[0011] Preferably, the molding and cooling steps are as follows: Step 1 Cooling and molding: After pouring is completed, the molten metal begins to stand in the mold and initially solidify, and liquid nitrogen is used to quickly cool the wind turbine casing casting so that the molten metal reaches a solidified state in a very short time; Step 2 Demolding and trimming: After the casting is completely solidified and cooled to room temperature, the casting is removed from the mold, and a grinder is used to remove the casting gate, riser and burrs, and the sand, coating and oxides on the surface of the casting are cleaned by mechanical cleaning.

[0012] Preferably, the subsequent heat treatment steps are as follows: Step 1: high-frequency quenching: placing the wind turbine housing casting in a hollow copper tube of the inductor, high-frequency alternating current generates an alternating magnetic field in the inductor, the input high-frequency alternating current frequency is 80,000 Hz, and an induced current of the same frequency is generated in the casting. The induced current is unevenly distributed in the casting, so that its surface current density is high and the internal current density is small. The skin effect causes the surface of the casting to be rapidly heated to 450-600°C, and high-frequency quenching is performed for 15-20s; Step 2: cooling after quenching: quickly placing the wind turbine housing casting in a salt bath quenching coolant and cooling it for 10-18s; Step 3: tempering and cooling: tempering the quenched wind turbine housing casting at 200-300°C for 120-180min to eliminate the internal stress generated during the quenching process. After the insulation is completed, the casting is taken out of the tempering furnace and naturally cooled to room temperature.

[0013] A wind turbine generator housing with high heat dissipation effect comprises a housing body, a wheel shell, a bearing mounting hole and a supporting base, wherein the wheel shell is mounted on the outside of the housing body, the bearing mounting hole is penetrated and opened on the outside of the wheel shell, and the supporting base is mounted on the bottom of the housing body.

[0014] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention utilizes pressure difference to hydraulically press molten aluminum alloy into the mold cavity for casting, controls low pressure to make the solidification process of the casting more uniform and stable, greatly reduces the cooling rate, realizes the refinement of the internal microstructure of the material, and thus obtains high-performance shell materials. The diffusion rate of solute atoms or molecules in the liquid material is much lower than the cooling rate, resulting in the formation of a non-equilibrium microstructure when the material solidifies. The rapid solidification technology can refine the grain structure of the casting. The fine-grained structure formed by rapid solidification helps to improve the thermal conductivity and mechanical properties of the material, thereby improving the heat dissipation capacity of the shell, reducing defects such as segregation and shrinkage, and enabling the wind turbine shell to dissipate heat more effectively during use.

[0015] 2. The present invention rapidly heats the surface of the aluminum alloy through high-frequency quenching, and rapidly increases the internal temperature through heat conduction, thereby ensuring a deeper hardened layer. High-frequency quenching has a fast heating speed and a short time, which can reduce the thermal stress and structural stress of the aluminum alloy during the heating process, thereby reducing the risk of deformation and cracking, ensuring the uniformity of the internal structure of the material, and significantly improving the hardness, wear resistance, fatigue resistance and other mechanical properties of the aluminum alloy, thereby enhancing the durability and safety of the wind turbine casing. Through heat treatment processes such as annealing, normalizing, and quenching, the internal structure of the casting can be improved, its thermal conductivity and thermal stability can be improved, and the heat dissipation effect of the generator casing can be further enhanced. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 The present invention is a process flow chart of the casting process of the wind turbine generator housing; Figure 2 It is a schematic diagram of the three-dimensional structure of the shell of the wind turbine generator set of the present invention.

[0017] In the figure: 1. Shell body; 2. Wheel housing; 3. Bearing mounting hole; 4. Supporting base. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", "front end", "rear end", "two ends", "one end", "the other end" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0020] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "provided with", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection or a movable connection, or a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0021] Embodiment 1, an embodiment provided by the present invention: a wind turbine generator housing with high heat dissipation effect and a casting method thereof, the wind turbine generator housing comprising a housing body 1, a wheel housing 2, a bearing mounting hole 3 and a supporting base 4, the wheel housing 2 is mounted on the outside of the housing body 1, the bearing mounting hole 3 is penetrated and opened on the outside of the wheel housing 2, and the supporting base 4 is mounted on the bottom of the housing body 1 The casting method of the wind turbine generator housing with high heat dissipation effect comprises the following steps: 1. material preparation and pretreatment; 2. mold manufacturing and processing; 3. smelting and pouring; 4. molding and cooling; 5. subsequent heat treatment; The material preparation and pretreatment steps are as follows: soak the aluminum alloy block in 36% hydrochloric acid, which softens the rust on the aluminum alloy plate and makes it fall off. After the rust removal treatment, spray the aluminum alloy cleaning agent on the aluminum alloy surface and wipe it with a soft cloth to remove various oil stains, oxide layers, metal powders and stains on the aluminum alloy surface; The mold manufacturing and processing steps are as follows: according to the shape and specification drawings of the wind turbine shell, design a reasonable mold structure to ensure that the mold is easy to disassemble and clean, and the mold shrinkage rate is controlled at 1% to 3%. After cleaning the mold, use graphite lubricant for lubrication; The smelting and pouring steps are as follows: 1. Metal smelting: Place the aluminum alloy block in a vacuum melting furnace, close the furnace door and seal it. The vacuum pump draws out the gas inside the vacuum melting furnace. The vacuum time is 30 seconds. Turn on the vacuum melting furnace and raise the temperature in the furnace to the hot melting temperature of the aluminum alloy. The temperature is controlled at 740°C and the smelting time is 10 minutes to avoid excessive oxidation of the molten metal or the generation of other impurities. 2. Purification: During the vacuum melting process, an appropriate amount of argon is introduced to prevent oxidation of the molten metal surface and remove dissolved gases in the molten metal. 3. Mold preheating: Place the mold in the preheating furnace and heat the mold through the high temperature environment in the furnace. The heating temperature is maintained at 30°C to ensure that the mold is heated to the required temperature and remains stable. After the heating is completed, take the mold out of the preheating furnace and quickly install it in the pouring Position; 4. Vacuuming and filling: After ensuring that the metal is completely melted, adjust the heat source power of the vacuum melting furnace to adjust the pouring temperature. The pouring temperature is maintained at 750℃. Use a vacuum pump to evacuate the casting mold to remove air and impurities. After reaching the required vacuum degree, enter the filling stage. Control the pressure difference between the upper and lower pressure tanks so that the molten metal flows smoothly into the mold cavity under the action of the pressure difference. The pressure of the upper tank remains unchanged, and the pressure of the lower tank increases steadily to form a sufficient pressure difference so that the molten aluminum alloy metal liquid fills the cavity; 5. Boosting and maintaining pressure: After the metal filling is completed, pressurize the upper and lower pressure tanks at the same time to quickly raise the pressure to 350kPa to ensure that the metal completely fills every corner of the mold. After boosting, keep it at 400kPa for 15s so that the metal is fully solidified in the mold; The molding and cooling steps are as follows: 1. Cooling molding: After pouring, the molten metal begins to stand still in the mold and initially solidify. Liquid nitrogen is used to quickly cool the wind turbine shell casting, so that the molten metal reaches a solidified state in a very short time; 2. Demolding and finishing: After the casting is completely solidified and cooled to room temperature, the casting is taken out of the mold, and the casting gate, riser and burrs are removed by a grinder, and the sand, coating and oxide on the surface of the casting are cleaned by mechanical cleaning; The subsequent heat treatment steps are as follows: 1. High-frequency quenching: Place the wind turbine shell casting in the hollow copper tube of the inductor. High-frequency alternating current generates an alternating magnetic field in the inductor. The input high-frequency alternating current frequency is 80,000 Hz, and an induced current of the same frequency is generated in the casting. The induced current is unevenly distributed in the casting, so that its surface current density is high and the internal current density is small. The skin effect causes the casting surface to be rapidly heated to 450-600°C, and high-frequency quenching is performed for 20 seconds; 2. Cooling after quenching: The wind turbine shell casting is quickly placed in a salt bath quenching coolant and cooled for 18 seconds; 3. Tempering and cooling: The quenched wind turbine shell casting is tempered at 300°C for 120 minutes to eliminate the internal stress generated during the quenching process. After the insulation is completed, the casting is taken out of the tempering furnace and naturally cooled to room temperature.

[0022] Embodiment 2, an embodiment provided by the present invention: a wind turbine generator housing with high heat dissipation effect and a casting method thereof, the wind turbine generator housing comprising a housing body 1, a wheel housing 2, a bearing mounting hole 3 and a supporting base 4, the wheel housing 2 is mounted on the outside of the housing body 1, the bearing mounting hole 3 is penetrated and opened on the outside of the wheel housing 2, and the supporting base 4 is mounted on the bottom of the housing body 1 The casting method of the wind turbine generator housing with high heat dissipation effect comprises the following steps: 1. material preparation and pretreatment; 2. mold manufacturing and processing; 3. smelting and pouring; 4. molding and cooling; 5. subsequent heat treatment; The material preparation and pretreatment steps are as follows: soak the aluminum alloy block in 36% hydrochloric acid, which softens the rust on the aluminum alloy plate and makes it fall off. After the rust removal treatment, spray the aluminum alloy cleaning agent on the aluminum alloy surface and wipe it with a soft cloth to remove various oil stains, oxide layers, metal powders and stains on the aluminum alloy surface; The mold manufacturing and processing steps are as follows: according to the shape and specification drawings of the wind turbine shell, design a reasonable mold structure to ensure that the mold is easy to disassemble and clean, and the mold shrinkage rate is controlled at 1% to 3%. After cleaning the mold, use graphite lubricant for lubrication; The smelting and pouring steps are as follows: 1. Metal smelting: Place the aluminum alloy block in a vacuum melting furnace, close the furnace door and seal it. The vacuum pump draws out the gas inside the vacuum melting furnace. The vacuum time is 30 seconds. Turn on the vacuum melting furnace and raise the temperature in the furnace to the hot melting temperature of the aluminum alloy. The temperature is controlled at 740°C and the smelting time is 10 minutes to avoid excessive oxidation of the molten metal or the generation of other impurities. 2. Purification: During the vacuum melting process, an appropriate amount of argon is introduced to prevent oxidation of the surface of the molten metal and remove dissolved gases in the molten metal. 3. Mold preheating: Place the mold in the preheating furnace and heat the mold through the high temperature environment in the furnace. The heating temperature is maintained at 250°C to ensure that the mold is heated to the required temperature and remains stable. After heating, take the mold out of the preheating furnace and quickly install it in the pouring Injection position; 4. Vacuuming and filling: After ensuring that the metal is completely melted, adjust the heat source power of the vacuum melting furnace to adjust the pouring temperature. The pouring temperature is maintained at 750℃. Use a vacuum pump to evacuate the casting mold to remove air and impurities. After reaching the required vacuum degree, enter the filling stage. Control the pressure difference between the upper and lower pressure tanks so that the molten metal flows smoothly into the mold cavity under the action of the pressure difference. The pressure of the upper tank remains unchanged, and the pressure of the lower tank increases steadily to form a sufficient pressure difference so that the molten aluminum alloy metal liquid fills the cavity; 5. Boosting and maintaining pressure: After the metal filling is completed, pressurize the upper and lower pressure tanks at the same time to quickly raise the pressure to 350kPa to ensure that the metal completely fills every corner of the mold. After boosting, keep it at 400kPa for 15s so that the metal is fully solidified in the mold; The molding and cooling steps are as follows: 1. Cooling molding: After pouring, the molten metal begins to stand still in the mold and initially solidify. Liquid nitrogen is used to quickly cool the wind turbine shell casting, so that the molten metal reaches a solidified state in a very short time; 2. Demolding and finishing: After the casting is completely solidified and cooled to room temperature, the casting is taken out of the mold, and the casting gate, riser and burrs are removed by a grinder, and the sand, coating and oxide on the surface of the casting are cleaned by mechanical cleaning; The subsequent heat treatment steps are as follows: 1. High-frequency quenching: Place the wind turbine shell casting in the hollow copper tube of the inductor. High-frequency alternating current generates an alternating magnetic field in the inductor. The input high-frequency alternating current frequency is 80,000 Hz, and an induced current of the same frequency is generated in the casting. The induced current is unevenly distributed in the casting, so that its surface current density is high and the internal current density is small. The skin effect causes the casting surface to be rapidly heated to 450-600°C, and high-frequency quenching is performed for 20 seconds; 2. Cooling after quenching: The wind turbine shell casting is quickly placed in a salt bath quenching coolant and cooled for 18 seconds; 3. Tempering and cooling: The quenched wind turbine shell casting is tempered at 300°C for 120 minutes to eliminate the internal stress generated during the quenching process. After the insulation is completed, the casting is taken out of the tempering furnace and naturally cooled to room temperature.

[0023] Embodiment 3, an embodiment provided by the present invention: a wind turbine generator housing with high heat dissipation effect and a casting method thereof, the wind turbine generator housing comprising a housing body 1, a wheel housing 2, a bearing mounting hole 3 and a supporting base 4, the wheel housing 2 is mounted on the outside of the housing body 1, the bearing mounting hole 3 is penetrated and opened on the outside of the wheel housing 2, and the supporting base 4 is mounted on the bottom of the housing body 1 The casting method of the wind turbine generator housing with high heat dissipation effect comprises the following steps: 1. material preparation and pretreatment; 2. mold manufacturing and processing; 3. smelting and pouring; 4. molding and cooling; 5. subsequent heat treatment; The material preparation and pretreatment steps are as follows: soak the aluminum alloy block in 36% hydrochloric acid, which softens the rust on the aluminum alloy plate and makes it fall off. After the rust removal treatment, spray the aluminum alloy cleaning agent on the aluminum alloy surface and wipe it with a soft cloth to remove various oil stains, oxide layers, metal powders and stains on the aluminum alloy surface; The mold manufacturing and processing steps are as follows: according to the shape and specification drawings of the wind turbine shell, design a reasonable mold structure to ensure that the mold is easy to disassemble and clean, and the mold shrinkage rate is controlled at 1% to 3%. After cleaning the mold, use graphite lubricant for lubrication; The smelting and pouring steps are as follows: 1. Metal smelting: Place the aluminum alloy block in a vacuum melting furnace, close the furnace door and seal it. The vacuum pump draws out the gas inside the vacuum melting furnace. The vacuum time is 30 seconds. Turn on the vacuum melting furnace and raise the temperature in the furnace to the hot melting temperature of the aluminum alloy. The temperature is controlled at 740°C and the smelting time is 10 minutes to avoid excessive oxidation of the molten metal or the generation of other impurities. 2. Purification: During the vacuum melting process, an appropriate amount of argon is introduced to prevent oxidation of the surface of the molten metal and remove dissolved gases in the molten metal. 3. Mold preheating: Place the mold in the preheating furnace and heat the mold through the high temperature environment in the furnace. The heating temperature is maintained at 300°C to ensure that the mold is heated to the required temperature and remains stable. After heating, take the mold out of the preheating furnace and quickly install it in the pouring Injection position; 4. Vacuuming and filling: After ensuring that the metal is completely melted, adjust the heat source power of the vacuum melting furnace to adjust the pouring temperature. The pouring temperature is maintained at 750℃. Use a vacuum pump to evacuate the casting mold to remove air and impurities. After reaching the required vacuum degree, enter the filling stage. Control the pressure difference between the upper and lower pressure tanks so that the molten metal flows smoothly into the mold cavity under the action of the pressure difference. The pressure of the upper tank remains unchanged, and the pressure of the lower tank increases steadily to form a sufficient pressure difference so that the molten aluminum alloy metal liquid fills the cavity; 5. Boosting and maintaining pressure: After the metal filling is completed, pressurize the upper and lower pressure tanks at the same time to quickly raise the pressure to 350kPa to ensure that the metal completely fills every corner of the mold. After boosting, keep it at 400kPa for 15s so that the metal is fully solidified in the mold; The molding and cooling steps are as follows: 1. Cooling molding: After pouring, the molten metal begins to stand still in the mold and initially solidify. Liquid nitrogen is used to quickly cool the wind turbine shell casting, so that the molten metal reaches a solidified state in a very short time; 2. Demolding and finishing: After the casting is completely solidified and cooled to room temperature, the casting is taken out of the mold, and the casting gate, riser and burrs are removed by a grinder, and the sand, coating and oxide on the surface of the casting are cleaned by mechanical cleaning; The subsequent heat treatment steps are as follows: 1. High-frequency quenching: Place the wind turbine shell casting in the hollow copper tube of the inductor. High-frequency alternating current generates an alternating magnetic field in the inductor. The input high-frequency alternating current frequency is 80,000 Hz, and an induced current of the same frequency is generated in the casting. The induced current is unevenly distributed in the casting, so that its surface current density is high and the internal current density is small. The skin effect causes the casting surface to be rapidly heated to 450-600°C, and high-frequency quenching is performed for 20 seconds; 2. Cooling after quenching: The wind turbine shell casting is quickly placed in a salt bath quenching coolant and cooled for 18 seconds; 3. Tempering and cooling: The quenched wind turbine shell casting is tempered at 300°C for 120 minutes to eliminate the internal stress generated during the quenching process. After the insulation is completed, the casting is taken out of the tempering furnace and naturally cooled to room temperature.

[0024] Embodiment 4, an embodiment provided by the present invention: a wind turbine generator housing with high heat dissipation effect and a casting method thereof, the wind turbine generator housing comprising a housing body 1, a wheel housing 2, a bearing mounting hole 3 and a supporting base 4, the wheel housing 2 is mounted on the outside of the housing body 1, the bearing mounting hole 3 is penetrated and opened on the outside of the wheel housing 2, and the supporting base 4 is mounted on the bottom of the housing body 1 The casting method of the wind turbine generator housing with high heat dissipation effect comprises the following steps: 1. material preparation and pretreatment; 2. mold manufacturing and processing; 3. smelting and pouring; 4. molding and cooling; 5. subsequent heat treatment; The material preparation and pretreatment steps are as follows: soak the aluminum alloy block in 36% hydrochloric acid, which softens the rust on the aluminum alloy plate and makes it fall off. After the rust removal treatment, spray the aluminum alloy cleaning agent on the aluminum alloy surface and wipe it with a soft cloth to remove various oil stains, oxide layers, metal powders and stains on the aluminum alloy surface; The mold manufacturing and processing steps are as follows: according to the shape and specification drawings of the wind turbine shell, design a reasonable mold structure to ensure that the mold is easy to disassemble and clean, and the mold shrinkage rate is controlled at 1% to 3%. After cleaning the mold, use graphite lubricant for lubrication; The smelting and pouring steps are as follows: 1. Metal smelting: put the aluminum alloy block into the vacuum melting furnace, close the furnace door and seal it, the vacuum pump draws out the gas inside the vacuum melting furnace, the vacuum time is 30s, turn on the vacuum melting furnace, raise the temperature in the furnace to the hot melting temperature of the aluminum alloy, the temperature is controlled at 740℃, the smelting time is 10min, avoid excessive oxidation of the molten metal or the generation of other impurities; 2. Purification: introduce an appropriate amount of argon gas during the vacuum melting process to prevent oxidation of the molten metal surface and remove dissolved gases in the molten metal; 3. Mold Preheating: Place the mold in the preheating furnace and heat the mold through the high temperature environment in the furnace. The heating temperature is maintained at 250°C to ensure that the mold is heated to the required temperature and remains stable. After heating, take the mold out of the preheating furnace and quickly install it in the pouring position; Fourth, pouring: The pouring temperature is maintained at 750°C, pour the molten aluminum alloy metal into the preheated mold and fill the cavity. The bottom pouring method is used to facilitate the metal liquid to enter the cavity smoothly, reduce turbulence and splashing, and the pouring speed is controlled at 150mm~400mm / min; The molding and cooling steps are as follows: 1. Cooling molding: After pouring, the molten metal begins to stand still in the mold and initially solidify. Liquid nitrogen is used to quickly cool the wind turbine shell casting, so that the molten metal reaches a solidified state in a very short time; 2. Demolding and finishing: After the casting is completely solidified and cooled to room temperature, the casting is taken out of the mold, and the casting gate, riser and burrs are removed by a grinder, and the sand, coating and oxide on the surface of the casting are cleaned by mechanical cleaning; The subsequent heat treatment steps are as follows: 1. High-frequency quenching: Place the wind turbine shell casting in the hollow copper tube of the inductor. High-frequency alternating current generates an alternating magnetic field in the inductor. The input high-frequency alternating current frequency is 80,000 Hz, and an induced current of the same frequency is generated in the casting. The induced current is unevenly distributed in the casting, so that its surface current density is high and the internal current density is small. The skin effect causes the casting surface to be rapidly heated to 450-600°C, and high-frequency quenching is performed for 20 seconds; 2. Cooling after quenching: The wind turbine shell casting is quickly placed in a salt bath quenching coolant and cooled for 18 seconds; 3. Tempering and cooling: The quenched wind turbine shell casting is tempered at 300°C for 120 minutes to eliminate the internal stress generated during the quenching process. After the insulation is completed, the casting is taken out of the tempering furnace and naturally cooled to room temperature.

[0025] Embodiment 5, an embodiment provided by the present invention: a wind turbine generator housing with high heat dissipation effect and a casting method thereof, the wind turbine generator housing comprising a housing body 1, a wheel housing 2, a bearing mounting hole 3 and a supporting base 4, the wheel housing 2 is mounted on the outside of the housing body 1, the bearing mounting hole 3 is penetrated and opened on the outside of the wheel housing 2, and the supporting base 4 is mounted on the bottom of the housing body 1 The casting method of the wind turbine generator housing with high heat dissipation effect comprises the following steps: 1. material preparation and pretreatment; 2. mold manufacturing and processing; 3. smelting and pouring; 4. molding and cooling; 5. subsequent heat treatment; The material preparation and pretreatment steps are as follows: soak the aluminum alloy block in 36% hydrochloric acid, which softens the rust on the aluminum alloy plate and makes it fall off. After the rust removal treatment, spray the aluminum alloy cleaning agent on the aluminum alloy surface and wipe it with a soft cloth to remove various oil stains, oxide layers, metal powders and stains on the aluminum alloy surface; The mold manufacturing and processing steps are as follows: according to the shape and specification drawings of the wind turbine shell, design a reasonable mold structure to ensure that the mold is easy to disassemble and clean, and the mold shrinkage rate is controlled at 1% to 3%. After cleaning the mold, use graphite lubricant for lubrication; The smelting and pouring steps are as follows: 1. Metal smelting: Place the aluminum alloy block in a vacuum melting furnace, close the furnace door and seal it. The vacuum pump draws out the gas inside the vacuum melting furnace. The vacuum time is 30 seconds. Turn on the vacuum melting furnace and raise the temperature in the furnace to the hot melting temperature of the aluminum alloy. The temperature is controlled at 740°C and the smelting time is 10 minutes to avoid excessive oxidation of the molten metal or the generation of other impurities. 2. Purification: During the vacuum melting process, an appropriate amount of argon is introduced to prevent oxidation of the surface of the molten metal and remove dissolved gases in the molten metal. 3. Mold preheating: Place the mold in the preheating furnace and heat the mold through the high temperature environment in the furnace. The heating temperature is maintained at 250°C to ensure that the mold is heated to the required temperature and remains stable. After heating, take the mold out of the preheating furnace and quickly install it in the pouring Injection position; 4. Vacuuming and filling: After ensuring that the metal is completely melted, adjust the heat source power of the vacuum melting furnace to adjust the pouring temperature. The pouring temperature is maintained at 750℃. Use a vacuum pump to evacuate the casting mold to remove air and impurities. After reaching the required vacuum degree, enter the filling stage. Control the pressure difference between the upper and lower pressure tanks so that the molten metal flows smoothly into the mold cavity under the action of the pressure difference. The pressure of the upper tank remains unchanged, and the pressure of the lower tank increases steadily to form a sufficient pressure difference so that the molten aluminum alloy metal liquid fills the cavity; 5. Boosting and maintaining pressure: After the metal filling is completed, pressurize the upper and lower pressure tanks at the same time to quickly raise the pressure to 350kPa to ensure that the metal completely fills every corner of the mold. After boosting, keep it at 400kPa for 15s so that the metal is fully solidified in the mold; The molding and cooling steps are as follows: 1. Cooling molding: After pouring, the molten metal begins to stand still in the mold and initially solidify. Liquid nitrogen is used to quickly cool the wind turbine shell casting, so that the molten metal reaches a solidified state in a very short time; 2. Demolding and finishing: After the casting is completely solidified and cooled to room temperature, the casting is taken out of the mold, and the casting gate, riser and burrs are removed by a grinder, and the sand, coating and oxide on the surface of the casting are cleaned by mechanical cleaning; The subsequent heat treatment steps are as follows: 1. Ordinary quenching: Place the wind turbine shell casting in a quenching furnace and quench the casting at 450-600°C for 8 minutes; 2. Cooling after quenching: Quickly place the wind turbine shell casting in a salt bath quenching coolant and cool it for 18 seconds; 3. Tempering and cooling: Temper the quenched wind turbine shell casting at 300°C for 120 minutes to eliminate the internal stress generated during the quenching process. After the insulation is completed, take the casting out of the tempering furnace and cool it naturally to room temperature.

[0026] Performance Test: 1. Heat dissipation capacity: Temperature monitoring points are arranged at key locations of the wind turbine shell, and wireless temperature measuring equipment is used to monitor temperature changes in real time. Computational fluid dynamics methods are used to simulate and analyze the airflow organization in the wind turbine nacelle to evaluate the impact of the shell structure on the heat dissipation performance. Through modeling and simulation, the flow of air in the nacelle and how heat is dissipated to the external environment can be intuitively seen, thereby evaluating the heat dissipation capacity. 2. Fatigue strength: Use a universal testing machine to conduct tensile, compression, bending and other mechanical property tests on the wind turbine casing to obtain key parameters such as the material's yield strength, tensile strength, and elastic modulus, simulate the alternating loads in actual operation, observe and record the process of fatigue crack initiation, expansion, and fracture of the sample, and evaluate the material's fatigue life and fatigue strength.

[0027] The test data of each embodiment under the same test conditions are shown in Table 1

[0028] Table 1 It can be seen from the experimental data in Table 1 that when the mold preheating temperature is controlled at 250℃, the pressure difference is used to hydraulically press the molten aluminum alloy into the mold cavity for casting, which greatly reduces the cooling rate and realizes the refinement of the internal microstructure of the material. The fine-grained structure formed by rapid solidification improves the heat dissipation capacity of the shell, so that the wind turbine shell can dissipate heat more effectively during use. Rapid heating of the aluminum alloy surface by high-frequency quenching can reduce the thermal stress and structural stress of the aluminum alloy during the heating process, thereby reducing the risk of deformation and cracking. The fatigue resistance of the aluminum alloy is enhanced, and the thermal conductivity and thermal stability of the wind turbine shell are improved.

[0029] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

Claims

1. A method for casting a wind turbine housing with high heat dissipation effect, characterized in that: The process includes the following steps:

1. Material preparation and pretreatment; 2. Mold manufacturing and processing; 3. Melting and pouring; 4. Molding and cooling; 5. Subsequent heat treatment; The smelting and pouring process includes the following steps:

1. metal smelting; 2. purification treatment; 3. mold preheating; 4. vacuuming and filling; 5. pressure increasing and pressure maintaining.

2. A method for casting a wind turbine generator housing with high heat dissipation effect according to claim 1, characterized in that: The material preparation and pretreatment steps are as follows: the aluminum alloy block is immersed in 36% hydrochloric acid, the hydrochloric acid softens the rust on the aluminum alloy plate and causes it to fall off, and after the rust removal treatment, the aluminum alloy cleaning agent is sprayed on the surface of the aluminum alloy and wiped with a soft cloth to remove various oil stains, oxide layers, metal powders and stains on the surface of the aluminum alloy.

3. The method for casting a wind turbine generator housing with high heat dissipation effect according to claim 1, characterized in that: The mold manufacturing and processing steps are as follows: according to the shape and specification drawings of the wind turbine shell, a reasonable mold structure is designed to ensure that the mold is easy to disassemble and clean, and the mold shrinkage rate is controlled at 1% to 3%. After cleaning the mold, it is lubricated with graphite lubricant.

4. The method for casting a wind turbine generator housing with high heat dissipation effect according to claim 1, characterized in that: The smelting and pouring steps are as follows: Step (1) Metal smelting: Place the aluminum alloy block in a vacuum smelting furnace, close the furnace door and seal it, use a vacuum pump to draw out the gas inside the vacuum smelting furnace, and evacuate for 30 seconds. Then, start the vacuum smelting furnace, raise the temperature in the furnace to the hot melting temperature of the aluminum alloy, control the temperature at 700°C to 740°C, and smelt for 10 minutes to 20 minutes to avoid excessive oxidation of the molten metal or the generation of other impurities. Step (2) Purification: During the vacuum smelting process, introduce an appropriate amount of argon gas to prevent oxidation of the surface of the molten metal and remove dissolved gas in the molten metal. Step (3) Mold preheating: Place the mold in a preheating furnace, heat the mold through the high temperature environment in the furnace, and maintain the heating temperature at 100°C to 250°C to ensure that the mold is heated to the required temperature and remains stable. After heating, take the mold out of the preheating furnace and Rapidly install it to the pouring position; step (4) vacuuming and filling: after ensuring that the metal is completely melted, adjust the heat source power of the vacuum melting furnace to adjust the pouring temperature, and maintain the pouring temperature at 680°C to 750°C. Use a vacuum pump to vacuum the casting mold to remove air and impurities therein. After reaching the required vacuum degree, enter the filling stage, and control the pressure difference between the upper and lower pressure tanks so that the molten metal flows smoothly into the mold cavity under the action of the pressure difference. The pressure of the upper tank remains unchanged, and the pressure of the lower tank increases steadily to form a sufficient pressure difference so that the molten aluminum alloy metal liquid fills the cavity; step (5) pressure increase and pressure maintenance: after the metal filling is completed, pressurize the upper and lower pressure tanks at the same time, so that the pressure quickly rises to 350 kPa to ensure that the metal completely fills every corner of the mold. After the pressure is increased, it is maintained at 400 kPa for 15 to 20 seconds so that the metal is fully solidified in the mold.

5. The method for casting a wind turbine generator housing with high heat dissipation effect according to claim 1, characterized in that: The molding and cooling steps are as follows: step (1) cooling molding: after the pouring is completed, the molten metal begins to stand in the mold and initially solidify, and liquid nitrogen is used to quickly cool the wind turbine generator housing casting so that the molten metal reaches a solidified state in a very short time; step (2) demoulding and trimming: after the casting is completely solidified and cooled to room temperature, the casting is taken out of the mold, and the casting gate, riser and burrs are removed by a grinder, and the sand, coating and oxide on the surface of the casting are cleaned by mechanical cleaning.

6. The method for casting a wind turbine generator housing with high heat dissipation effect according to claim 1, characterized in that: The subsequent heat treatment steps are as follows: Step (1) high-frequency quenching: placing the wind turbine shell casting in a hollow copper tube of an inductor, high-frequency alternating current generates an alternating magnetic field in the inductor, the input high-frequency alternating current frequency is 80,000 Hz, and an induced current of the same frequency is generated in the casting. The induced current is unevenly distributed in the casting, so that its surface current density is high and the internal current density is small. The skin effect causes the surface of the casting to be rapidly heated to 450-600°C, and high-frequency quenching is performed for 15-20 seconds; Step (2) cooling after quenching: quickly placing the wind turbine shell casting in a salt bath quenching coolant and cooling it for 10-18 seconds; Step (3) tempering and cooling: tempering the quenched wind turbine shell casting at 200-300°C for 120-180 minutes to eliminate the internal stress generated during the quenching process. After the insulation is completed, the casting is taken out of the tempering furnace and naturally cooled to room temperature.

7. A wind turbine generator housing with high heat dissipation effect cast by the casting method according to any one of claims 1 to 6, characterized in that: The invention comprises a housing body (1), a wheel housing (2), a bearing mounting hole (3) and a supporting base (4), wherein the wheel housing (2) is mounted on the outside of the housing body (1), the bearing mounting hole (3) is penetrated and opened on the outside of the wheel housing (2), and the supporting base (4) is mounted on the bottom of the housing body (1).

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