Casting equipment for ultra-large casting production
By using gradient insulation layer and flow field intervention components in the combined casting equipment, the temperature gradient and pore problems in traditional combined casting molds are solved, and high-quality super-large casting production is achieved.
Patent Information
- Application Number
- CN202510508462.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-22
- Publication Date
- 2025-08-01
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
The linear runner design of traditional combined casting molds results in a temperature gradient of the front edge of the metal liquid greater than 50℃/cm. When the temperature difference exceeds the critical value, cold space defects are formed, and the residual gas in the combined casting forms pores in the junction area of the cavity, affecting the shape and strength of the workpiece.
The gradient insulation layer and flow field intervention components are used, including nano-aerogels and multi-layer reflectors, and the insulation layer of the insulation layer is controlled by combining the pulsed magnetic field generator to eliminate the oxide film, a micro-Coriolis force flowmeter is used to adjust the flow rate, and a micro-exhaust tank and vacuum pump system are set for vacuuming to ensure that the temperature gradient and vacuum degree of the metal liquid are within the appropriate range.
The temperature gradient of the metal liquid is controlled within ±8°C, the cooling separation rate is less than 0.3%, and the porosity is less than 0.5%, which improves the tensile strength and appearance quality of the castings.
Smart Images
Figure CN120394820A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of casting equipment, and more specifically, it relates to a combined casting equipment for extra-large casting production. Background Art
[0002] In the field of casting large and complex components, the following phenomena occur in the multi-channel combined casting process. The linear gating design of traditional combined casting molds easily leads to a temperature gradient of the molten metal front > 50 °C / cm. When the melts from different paths converge, the temperature difference exceeds the critical value (for example, about 30 °C for aluminum alloy and 60 °C for titanium alloy), resulting in cold shut defects. At the same time, the residual gas in the combined casting forms pores with a diameter of Φ0.5 - 2 mm in the cavity intersection area, causing poor appearance and strength of the workpiece. Summary of the Invention
[0003] The present invention provides a combined casting equipment for extra-large casting production to solve the technical problems in the related art.
[0004] The present invention provides a combined casting equipment for extra-large casting production, including a frame, a storage tank, a melting furnace, a metering furnace, and a combined casting device. The storage tank, the melting furnace, and the metering furnace are distributed on the frame from high to low in sequence, and the output end of the metering furnace is connected to the combined casting mold of the combined casting device; The combined casting mold includes an upper mold, a lower mold, a feeding port group, and a flow field intervention component. The upper mold and the lower mold are arranged in parallel in the same vertical direction. At least two groups of symmetrically distributed feeding port groups are provided on the outer surface of the combined casting mold. Each group of feeding port groups contains 2 pouring ports arranged in an outer eight-character shape. The number of feeding port groups corresponds to the number of discharge ends of the combined storage layer, melting layer, and metering layer. A gradient heat preservation layer is arranged between the connection of the metering furnace and the feeding port group. The near-furnace end of the gradient heat preservation layer uses a heat preservation layer of nano-aerogel, and the near-mold end of the gradient heat preservation layer uses a heat preservation layer of a multi-layer reflection screen. When the flow path length between the metering furnace and the feeding port group is the same, the temperature fluctuation control is achieved by setting different heat preservation length ratios at the near-furnace end and the near-mold end; The flow field intervention component includes a pulsed magnetic field generator and a temperature sensor. The frequency of the pulsed magnetic field generator is between 10 - 50 kHz. The pulsed magnetic field generator is used to eliminate the oxide film on the surface of the molten metal and promote the molecular-level fusion of multiple strands of molten metal; The copper coil of the pulsed magnetic field generator and the temperature sensing end of the temperature sensor are both encapsulated in epoxy resin in the inner surface of the intersection area of the mold cavity in the combined casting mold at a position 2 mm - 5 mm below the surface.
[0005] Furthermore, a micro Coriolis flowmeter is provided at the entrance of the pouring port. When the flow velocity difference between adjacent pouring ports > 3%, the opening degree of the valve body on the corresponding pouring port is automatically adjusted.
[0006] Further, a sealing structure is also provided at the junction of the upper die and the lower die. The upper die is provided with a convex ring, and the lower die is correspondingly provided with a groove. A high-temperature-resistant graphite tape is filled in the connection gap between the convex ring and the groove.
[0007] Further, a mold cavity is provided between the upper die and the lower die. At the same time, except for the interface part of the mold cavity between the upper die and the lower die, it is a parting surface. The pouring gate is connected to the mold cavity. A micro-venting groove with a V-shaped cross-section is provided on the parting surface, and through holes are spacedly arranged at the bottom of the micro-venting groove. The through holes are evacuated by a vacuum control assembly.
[0008] Further, the vacuum control assembly includes a vacuum pump, a standby pump, a differential pressure sensor, and a stainless steel bellows. The micro-venting groove on the parting surface is connected to the vacuum pump through the stainless steel bellows by a quick-change clamp. The detection end of the differential pressure sensor is connected across the inlet and outlet of the vacuum pump. When the differential pressure of the differential pressure sensor exceeds the limit, the standby pump is started.
[0009] Further, the feeding end of the storage bin conveys raw materials by a conveyor belt. The conveyor belt is a 304 stainless steel mesh belt and is driven by a frequency conversion motor.
[0010] Further, SiC spiral electric heating wires are embedded in the furnace wall inside the melting furnace. An outlet nozzle is provided at the bottom end of the melting furnace. The three-way valve provided on the outlet nozzle is synchronously driven by a double servo motor. One of the outlet pipelines of the three-way valve is connected to the waste gas treatment port at an inclined angle.
[0011] Further, a dry pot is arranged vertically below the melting furnace. A solution basin is fixed to the bottom of the dry pot by bolts. A honeycomb-shaped flow dividing grid is provided inside the solution basin. At the same time, a weighing alarm is provided at the bottom of the dry pot. When the weighing alarm detects overweight, it triggers an audible and visual alarm and cuts off the power supply of the melting furnace.
[0012] Further, a float structure is built in the metering furnace. The float structure includes a float and an intelligent valve. The float is connected to the ceramic valve core of the intelligent valve through a connecting rod. The displacement of the float linearly corresponds to the valve opening of the intelligent valve.
[0013] Further, a linkage structure is provided at the top end of the storage bin. The linkage structure is an elastic flap and an air extraction pump. The elastic flap includes a silica gel sealing piece and a spring steel bracket. The silica gel sealing piece is arranged on the outer side wall of the spring steel bracket. When the elastic flap is opened, the air extraction pump starts to operate.
[0014] The beneficial effects of the present invention are as follows: By setting the pulsed magnetic field of the flow field intervention component in the present invention, the temperature gradient at the front of the molten metal is controlled within a certain range, and then the temperature difference in the confluence area is controlled within 60% of the critical value. A micro-venting groove is provided and cooperated with a vacuum pump to improve the vacuum degree of the cavity. Before combined casting, in cooperation with the flow dividing grid in the metering furnace and the PID speed control of the flow field intervention component, the tensile strength of the casting is improved. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Figure 1 This is a front view of a combined casting equipment for ultra-large casting production proposed by the present invention; Figure 2 The present invention Figure 1 A vertical section of the middle furnace; Figure 3 The present invention Figure 1 Schematic diagram of the internal structure of the medium gradient insulation layer; Figure 4 The present invention Figure 1 Schematic diagram of the structure of the Zhonghe casting mold; Figure 5 The present invention Figure 4 Enlarged view of section A.
[0016] In the figure: 100, frame; 200, storage box; 300, furnace; 310, overflow pipe; 320, dry pot; 330, solution basin; 340, three-way valve; 350, exhaust gas treatment port; 360, SiC spiral heating wire; 370, diverter grid; 400, quantitative furnace; 500, casting equipment; 600, casting mold; 610, upper mold; 620, lower mold; 630, parting surface; 640, micro exhaust groove; 650, high temperature resistant graphite tape; 660, mold cavity; 670, through hole; 680, pulse magnetic field generator; 700, gradient insulation layer; 710, near furnace end; 720, near mold end; 800, feed port group; 900, conveyor belt. DETAILED DESCRIPTION
[0017] The subject matter described herein will now be discussed with reference to exemplary embodiments. It should be understood that these embodiments are discussed solely to enable those skilled in the art to better understand and implement the subject matter described herein, and that the functions and arrangements of the elements discussed may be varied without departing from the scope of this specification. Various examples may omit, substitute, or add various processes or components as needed. In addition, features described with respect to some examples may also be combined in other examples.
[0018] like Figures 1-5 As shown, a combined casting equipment for ultra-large casting production includes a frame 100. The frame 100 is a four-layer steel structure frame. Different layers of the frame 100 are respectively arranged as a storage layer, a smelting layer, a quantitative layer, and a combined casting layer. The storage layer, the smelting layer, the quantitative layer, and the combined casting layer are respectively provided with a storage box 200, a melting furnace 300, a quantitative furnace 400, and a combined casting equipment 500. The middle part of the casting device 500 is provided with a casting mold 600 for forming the workpiece to be processed; Among them, the combined casting mold 600 includes an upper mold 610, a lower mold 620, a feeding port group 800, and a flow field intervention component; The upper mold 610 and the lower mold 620 are arranged in parallel in the same vertical direction. At least two groups of feeding port groups 800 symmetrically distributed on the outer surface are provided on the combined casting mold 600. Each group of feeding port groups 800 contains 2 pouring ports arranged in an outer eight-character shape. The distance between the pouring ports is greater than 5 times the diameter of the feeding port group 800, realizing the diversion and confluence filling of the molten metal; The number of the feeding port groups 800 corresponds to the number of the discharge ends of the combined storage layer, melting layer, and metering layer. That is, the output ends of the storage layer, melting layer, and metering layer are connected to the combined casting mold 600 through the feeding port groups 800. A gradient heat preservation layer 700 is arranged between the connecting metering furnace 400 and the feeding port groups 800. The near-furnace end 710 of the gradient heat preservation layer 700 adopts a heat preservation layer of nano-aerogel (thermal conductivity 0.018W / m·K), and the near-mold end 720 of the gradient heat preservation layer 700 adopts a heat preservation layer of a multi-layer reflection screen (thermal reflectivity > 95%), ensuring that the temperature fluctuation during the whole process of molten metal transmission is controlled within ±8°C; The gradient heat preservation layer 700 is set to maintain the optimal temperature for the molten state fusion between different metal materials. When the flow channel lengths between the metering furnace 400 and the feeding port groups 800 are the same, the temperature fluctuation control is realized through the set heat preservation length ratio of different near-furnace ends 710 and near-mold ends 720; Among them, the gradient heat preservation layer 700 adopts a parallel multi-channel structure, and the end of the gradient heat preservation layer 700 converges to the feeding end of the combined casting mold 600; It should be added that a micro-Coriolis flowmeter is arranged at the entrance of the pouring port. The sampling frequency of the micro-Coriolis flowmeter reaches 1000Hz, and a PID control model is established. When the flow velocity difference between adjacent pouring ports > 3%, the opening of the upper valve body of the pouring port is automatically adjusted. The pouring ports arranged in an outer eight-character shape are designed with an inclination angle of 30°, using gravity to compensate for the pressure difference between different pouring ports; A sealing structure is also provided at the joint of the upper mold 610 and the lower mold 620. The upper mold 610 is provided with a convex ring with a height of 8mm, and the lower mold 620 is correspondingly provided with a groove with a depth of 7.95mm. A high-temperature resistant graphite tape 650 is filled in the connection gap between the convex ring and the groove.
[0019] A mold cavity 660 is arranged between the upper mold 610 and the lower mold 620. At the same time, except for the interface part of the mold cavity 660 between the upper mold 610 and the lower mold 620, it is a parting surface 630. The pouring port communicates with the mold cavity 660. A micro-venting groove 640 with a V-shaped cross-section is arranged on the parting surface 630. Through holes 670 are opened every 2mm at the bottom of the micro-venting groove 640, and the through holes 670 are evacuated through a vacuum control component; The vacuum control assembly includes a vacuum pump, a standby pump, a differential pressure sensor, and a stainless-steel bellows. The micro-exhaust groove 640 of the parting surface 630 is connected to the vacuum pump through the stainless-steel bellows by a quick-change clamp. The detection end of the differential pressure sensor is bridged across the inlet and outlet of the vacuum pump. When the differential pressure of the differential pressure sensor exceeds the limit, the standby pump is started. The flow field intervention assembly includes a pulsed magnetic field generator 680 and a temperature sensor. The frequency of the pulsed magnetic field generator 680 is between 10 - 50 kHz. The pulsed magnetic field generator 680 is used to eliminate the oxide film on the surface of the molten metal and promote the molecular-level fusion of multiple strands of molten metal. The copper coil of the pulsed magnetic field generator 680 and the temperature-sensing end of the temperature sensor are both encapsulated with epoxy resin 2 - 5 mm below the inner surface of the intersection area of the mold cavity 660. It is powered by a high-frequency power supply (with adjustable power of 1 - 5 kW). The magnetic field strength is dynamically adjusted through the PID algorithm. The control signal of the pulsed magnetic field generator 680 is output through the AO terminal of the PLC module. The high-frequency power supply is connected to the copper coil through a shielded cable, and the outer layer of the shielded cable is coated with a high-temperature-resistant ceramic fiber sleeve. The top of the storage tank 200 is provided with a linkage structure between the elastic flap and the air extraction pump. The linkage structure is used to maintain the humidity < 5%RH. The elastic flap includes a silica gel sealing sheet and a spring steel bracket. The silica gel sealing sheet is arranged on the outer side wall of the spring steel bracket. When the elastic flap is opened, the air extraction pump is started (the air extraction rate ≥ 5L / s). The feeding end of the storage tank 200 uses a conveyor belt 900 to transport raw materials. The conveyor belt 900 uses a 304 stainless-steel mesh belt (mesh hole Φ3mm), which is driven by a variable-frequency motor, and the speed is fed back to the PLC module in real time.
[0020] The furnace wall inside the melting furnace 300 is embedded with SiC spiral heating wires 360 (spacing 10mm). There is a discharge nozzle at the bottom of the melting furnace 300. The three-way valve 340 installed on the discharge nozzle is driven synchronously by a double servo motor, and the opening and closing angle is fed back to the PLC module. One of the outlet pipelines of the three-way valve 340 is connected to the waste gas treatment port 350 at an angle of 15°. A dry pot 320 is arranged vertically below the melting furnace 300. The bottom of the dry pot 320 is fixed with a solution basin 330 by bolts. A honeycomb-shaped flow distribution grid 370 is arranged inside the solution basin 330. At the same time, a weighing alarm is arranged at the bottom of the dry pot 320. When the weighing alarm detects overweight, it triggers an audible and visual alarm and cuts off the power supply of the melting furnace 300. The overflow pipe 310 connected to the solution basin 330 extends to the workshop trench, and a spark-proof grille is arranged at the pipe orifice of the overflow pipe 310. [[ID= Among them, the metering furnace 400 is internally provided with a float structure, which includes a float and a smart valve. The float is connected to the ceramic valve core of the smart valve through a connecting rod. The displacement of the float of ±2 mm linearly corresponds to the valve opening of the smart valve of 0-100%. At the same time, the connecting rod of the smart valve and the float are connected through a universal joint to compensate for installation deviation; Among them, the DI terminal of the PLC module receives the dry contact signal of the weighing alarm, and the DO terminal of the PLC module controls the start and stop of the vacuum pump.
[0021] There is also a control cabinet, which is located on the outer wall of one side of the frame 100. The PLC module is built into the control box, and a human-machine interface and an emergency stop button are also provided on the control cabinet.
[0022] Its working principle is as follows: Stage 1: Raw material pretreatment When the elastic flap of the storage bin 200 is opened, the air extraction pump maintains the humidity <5%RH at a rate of ≥5L / s, and the 304 stainless steel mesh belt transports the raw materials to the melting furnace 300 at a speed matched by the PLC; The SiC spiral electric heating wire 360 is heated to the melting point of the metal +150°C, and the molten metal enters the dry pot 320 after being rectified by the honeycomb-shaped flow dividing grid 370.
[0023] Stage 2: Precise metering The float structure linearly controls the opening of the smart valve through displacement. At the outlet of the metering furnace 400, the double servo motors drive the valve body synchronously, and the opening angle error <0.1°; The nano-aerogel at the furnace-end 710 and the reflective screen at the mold-end 720 of the gradient insulation layer 700 work together to make the temperature fluctuation of the molten metal transmission ≤±8°C.
[0024] Stage 3: Composite casting and forming The outer bevel pouring port dynamically balances the flow rate difference through the micro Coriolis flowmeter, and the PID model automatically adjusts the valve body opening when the flow rate deviation >3%; The pulsed magnetic field generator 680 eliminates the oxide film at a high frequency of 10-50kHz. At the same time, the PID algorithm adjusts the magnetic field strength (1-5kW) according to the feedback of the temperature sensor to promote molecular-level fusion.
[0025] Stage 4: Exhaust guarantee The V-shaped micro exhaust groove 640 is connected to the vacuum pump through the through hole 670. When the pressure difference sensor detects that the vacuum degree deviates from the set value, the standby pump starts within <0.2s; The sealing structure of the parting surface 630 ensures that the leakage rate of the cavity 660 <0.05Pa·m³ / s.
[0026] Stage 5: Safety interlock When the weighing alarm exceeds the limit, the power supply of the furnace is cut off within 0.5 s, and the three-way valve 340 automatically switches to the waste gas treatment channel when the pressure in the solution basin 330 > 50 kPa; The PLC controls the whole process through DI / DO terminal networking. When the emergency stop button is triggered, vacuum maintenance and metal liquid interception are preferentially executed.
[0027] This process is controlled by a triple closed-loop of temperature - flow rate - pressure to achieve precision co-casting production with a cold shut rate < 0.3% and a porosity < 0.5%.
[0028] The above describes the embodiments of the present invention, but the present invention is not limited to the above specific embodiments. The above specific embodiments are merely illustrative and not restrictive. Under the inspiration of the present invention, those of ordinary skill in the art can also make many forms, all of which fall within the protection scope of the present invention.
Claims
1. A combined casting equipment for extra-large casting production, characterized in that It includes a frame (100), a storage bin (200), a melting furnace (300), a metering furnace (400) and a combined casting device (500). The storage bin (200), the melting furnace (300) and the metering furnace (400) are distributed on the frame (100) from high to low in sequence. The output end of the metering furnace (400) is connected to the combined casting die (600) of the combined casting device (500). The combined casting die (600) includes an upper die (610), a lower die (620), a charging port group (8) and a flow field intervention component. The upper die (610) and the lower die (620) are arranged in parallel on the same vertical line. At least two groups of charging port groups (800) symmetrically distributed on the outer facade are provided on the combined casting die (600). Each group of charging port groups (800) contains 2 pouring ports arranged in an outward V shape. The number of charging port groups (800) corresponds to the number of discharge ends of the combined storage layer, melting layer and metering layer. A gradient heat preservation layer (700) is arranged between the metering furnace (400) and the charging port group (800). The near-furnace end (710) of the gradient heat preservation layer (700) uses a heat preservation layer of nano-aerogel, and the near-die end (720) of the gradient heat preservation layer (700) uses a heat preservation layer of a multi-layer reflection screen. When the flow channel lengths between the metering furnace (400) and the charging port group (800) are the same, the temperature fluctuation control is realized by setting the heat preservation length ratios of different near-furnace ends (710) and near-die ends (720). The flow field intervention component includes a pulsed magnetic field generator (680) and a temperature sensor. The frequency of the pulsed magnetic field generator (680) is between 10 - 50 kHz. The pulsed magnetic field generator (680) is used to eliminate the oxide film on the surface of the molten metal and promote the molecular-level fusion of multiple strands of molten metal. The copper coil of the pulsed magnetic field generator (680) and the temperature sensing end of the temperature sensor are both encapsulated in epoxy resin at a position 2 - 5 mm below the inner surface of the intersection area of the die cavity (660) in the combined casting die (600).
2. The combined casting equipment for extra-large casting production according to claim 1, characterized in that, A micro Coriolis flowmeter is arranged at the entrance of the pouring port. When the flow velocity difference between adjacent pouring ports > 3%, the opening degree of the valve body on the corresponding pouring port is automatically adjusted.
3. The combined casting equipment for extra-large casting production according to claim 2, characterized in that, A sealing structure is also provided at the joint of the upper die (610) and the lower die (620). The upper die (610) is provided with a convex ring, and the lower die (620) is correspondingly provided with a groove. A high-temperature-resistant graphite tape (650) is filled in the connection gap between the convex ring and the groove.
4. A combined casting equipment for extra-large casting production according to claim 3, characterized in that, A die cavity (660) is arranged between the upper die (610) and the lower die (620). At the same time, except for the interface part of the die cavity (660) between the upper die (610) and the lower die (620), it is a parting surface (630). The pouring port communicates with the die cavity (660). A micro exhaust groove (640) with a V-shaped cross-section is arranged on the parting surface (630). Through holes (670) are arranged at intervals at the bottom of the micro exhaust groove (640). The through holes (670) are evacuated through a vacuum control component.
5. A combined casting equipment for super-large casting production according to claim 4, characterized in that, The vacuum control assembly includes a vacuum pump, a standby pump, a differential pressure sensor, and a stainless steel bellows. The stainless steel bellows is connected to the micro-exhaust groove (640) of the parting surface (630) and the vacuum pump through a quick-change clamp. The detection end of the differential pressure sensor is connected across the inlet and outlet of the vacuum pump. When the differential pressure of the differential pressure sensor exceeds the limit, the standby pump is started.
6. The combined casting equipment for extra-large casting production according to claim 5, characterized in that, The feeding end of the storage tank (200) uses a conveyor belt (900) to transport raw materials. The conveyor belt (900) is made of 304 stainless steel mesh belt and is driven by a variable-frequency motor.
7. A combined casting equipment for super-large casting production according to claim 6, characterized in that, SiC spiral electric heating wires (360) are embedded in the furnace wall inside the melting furnace (300). An outlet nozzle is provided at the bottom of the melting furnace (300). The three-way valve (340) provided on the outlet nozzle is driven synchronously by a double servo motor. One of the outlet pipelines of the three-way valve (340) is connected to the waste gas treatment port (350) at an inclined angle.
8. A combined casting equipment for extra-large casting production according to claim 7, characterized in that, A dry pot (320) is arranged vertically below the melting furnace (300). A solution basin (330) is fixed to the bottom of the dry pot (320) by bolts. A honeycomb-shaped flow dividing grid (370) is provided inside the solution basin (330). At the same time, a weighing alarm is provided at the bottom of the dry pot (320). When the weighing alarm detects overweight, it triggers an audible and visual alarm and cuts off the power supply of the melting furnace (300).
9. A combined casting equipment for extra-large casting production according to claim 8, characterized in that, Among them, a float structure is built in the metering furnace (400). The float structure includes a float and an intelligent valve. The float is connected to the ceramic valve core of the intelligent valve through a connecting rod. The displacement of the float linearly corresponds to the valve opening of the intelligent valve.
10. The combined casting equipment for extra-large casting production according to claim 9, characterized in that, Among them, a linkage structure is provided at the top of the storage tank (200). The linkage structure is an elastic flap and an air extraction pump. The elastic flap includes a silica gel sealing sheet and a spring steel bracket. The silica gel sealing sheet is arranged on the outer side wall of the spring steel bracket. When the elastic flap is opened, the air extraction pump starts to operate.