A composite roll casting porosity and shrinkage heating device and method

Abstract

The application discloses a kind of composite roller casting shrinkage hole heating device and method, according to the order of composite roller casting solidification gradually reaches solidus from bottom to top direction in sequence Arranging multiple groups of temperature measuring heating devices, and parallel distribution.Each group of temperature measuring heating device includes an infrared camera temperature measuring device, a heating device, a power device.Using infrared camera temperature measuring device to collect the temperature value of the outer surface of composite roller casting tool;Establish the temperature relationship between the temperature value of the outer surface of composite roller casting tool and the pouring center temperature value, center console real-time calculates the temperature difference between each temperature measuring point on the outer surface of composite roller casting tool, the temperature difference between the temperature value of the outer surface of tool when casting liquid pouring solidification reaches solidus and the temperature value of the outer surface of tool actually collected by infrared camera temperature measuring device, and control heating device to heat.The application can effectively solve the shrinkage hole invisible defect caused by unable sequential solidification during casting process.

Description

Technical Field

[0001] This invention relates to the field of heat treatment technology, and in particular to a heating device and method for heating shrinkage cavities in composite roll casting. Background Technology

[0002] The common method for manufacturing composite rolls is centrifugal composite casting. This method typically involves centrifugal casting to produce the outer layer or a combination of the outer and middle layers, followed by gravity casting to fill and produce the core. However, during the core filling process in composite roll casting, solidification cannot proceed sequentially from bottom to top. This results in the early solidification areas cutting off the feeding channels and creating shrinkage cavities. Consequently, the composite roll casting process becomes less than ideal, affecting the overall quality of the composite roll.

[0003] Currently, the composite roll casting process can be improved by temperature control, such as by using multiple temperature detection devices to monitor the temperature of the working layer in real time during the casting process, and adjusting the side heating device and the cylindrical heating device according to the temperature relationship. However, this can only reduce the overall temperature difference of the working layer during the casting process, and cannot directly maintain the sequential solidification of the composite roll from bottom to top. Therefore, it cannot directly eliminate the shrinkage porosity and shrinkage cavity problems that may occur during the composite roll casting process. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a heating device and method for shrinkage cavity in composite roll casting, thereby ensuring that the composite roll casting process is closer to an ideal casting and cooling process and improving the casting quality of composite rolls.

[0005] Therefore, the present invention provides the following technical solution:

[0006] This invention provides a heating device for shrinkage porosity in composite roll casting, comprising: a central control console, multiple sets of temperature measuring and heating devices, a lifting device, a balance ring, a fixed base, and a main power supply;

[0007] The fixed base is fixedly connected to the base of the composite roll casting fixture; the balance ring is located at the top of the composite roll casting fixture.

[0008] The lifting device includes a guide rail and a slider; the guide rail is vertically arranged between the fixed base and the balance ring; the slider is connected to the guide rail by a rolling element, and the slider can move up and down on the guide rail;

[0009] The temperature measuring and heating device includes an infrared camera temperature measuring device, a heating device, and a power device. Multiple infrared camera temperature measuring devices are arranged sequentially from bottom to top on the composite roll casting fixture, according to the order in which the composite roll casting gradually reaches the solidus line. The infrared camera temperature measuring devices are connected to the central control console for data communication. Multiple heating devices are connected sequentially from bottom to top via sliders to the guide rails, according to the order in which the composite roll casting gradually reaches the solidus line. The heating devices can move up and down along the guide rails. The power device is fixed together with the heating devices and has an electrical connection. The power device is connected to the main power supply via a wire. The main power supply is connected to the central control console via a wire.

[0010] Multiple heating devices and guide rails form a hollow frame structure, which is fitted onto the outside of the composite roll casting fixture.

[0011] Furthermore, the temperature measuring and heating device consists of five sets.

[0012] Furthermore, the first set of temperature measuring and heating devices is located in the upper middle part of the lower sand box, the second set of temperature measuring and heating devices is located in the middle of the groove on the lower side of the roller mold, the third set of temperature measuring and heating devices is located in the middle of the roller mold, the fourth set of temperature measuring and heating devices is located in the middle of the groove on the upper side of the roller mold, and the fifth set of temperature measuring and heating devices is located in the middle of the upper sand box.

[0013] Furthermore, the infrared camera temperature measurement device includes: an infrared camera thermometer and a mounting base for fixing the infrared camera thermometer, the mounting base being fixed on the composite roll casting fixture.

[0014] Furthermore, the heating device includes: a contour heating coil and a heating coil holder for fixing the contour heating coil; one end of the heating coil holder is fixedly connected to the guide rail slider, and the other end is fixedly connected to the power unit.

[0015] Furthermore, the power unit includes: a motor, a power unit housing, an upper power unit mounting bracket, a lower power unit mounting bracket, a left power unit mounting bracket, and a right power unit mounting bracket; the positive and negative poles of the contour heating coil are connected to the motor, and the motor is connected to the main power supply. The motor is fixed inside the power unit housing through the upper power unit mounting bracket, the lower power unit mounting bracket, the left power unit mounting bracket, and the right power unit mounting bracket. The power unit housing and the guide rail are connected by rolling elements, and the power unit can move up and down on the guide rail.

[0016] The present invention also provides a method for heating using the above-mentioned composite roll casting shrinkage cavity heating device, comprising:

[0017] Power on, multiple temperature measuring and heating devices reset and connect to the main power supply, ready for operation;

[0018] The infrared temperature measurement camera collects the temperature values ​​of each temperature measurement point on the outer surface of the composite roll casting fixture and sends them to the central control console in the form of mathematical signals. The central control console calculates the temperature value of the outer surface of the composite roll casting fixture at the instant when the casting liquid reaches the solidification line and obtains the theoretically calculated temperature value.

[0019] The casting and cooling process of composite rolls was simulated, and the temperature field cloud maps of each temperature measuring point of the rolls at each time stage were extracted to obtain the simulated temperature values.

[0020] A database is established, and the outer surface of the composite roll casting tool is radially divided into n segments for trimming. During the trimming of the i-th segment, the theoretically calculated temperature value is compared with the simulated temperature value to determine the error constant between the theoretically calculated temperature and the simulated temperature. The error constant obtained from each comparison is stored in the database; i is an integer from 0 to n.

[0021] The central control console determines the temperature difference between the theoretically calculated temperature value and the temperature value at each temperature measuring point, as well as the temperature difference between each temperature measuring point in the casting center. Based on the temperature difference between the theoretically calculated temperature value and the temperature value at each temperature measuring point, as well as the temperature difference between each temperature measuring point in the casting center, the operating mode of each heating device is determined.

[0022] Determine the output power of each heating device;

[0023] The central control console feeds back the output power of each heating device to each heating device to control heating, and each heating device moves and heats within its movable range.

[0024] Furthermore, the central control console calculates the surface temperature of the outer layer of the composite roll casting fixture at the instant the molten casting solidifies to the solidus line, obtaining the theoretically calculated temperature value, including:

[0025] Composite roll casting is divided into three parts: upper, middle, and lower. For each part:

[0026] The casting consists of three layers from the inside out. The inner layer has a radius of r1, the middle layer has a thickness of x1 and a thermal conductivity of λ1. The inner and middle layers are metal and sand, with a convective heat transfer coefficient of α1. The outer layer has a thickness of x2 and a thermal conductivity of λ2. The outer layer is metal and air, with a convective heat transfer coefficient of α0. The room temperature in the casting workshop is set to t0. The instantaneous temperature at which the molten casting reaches the solidification line is t1. The interface temperature between the inner and middle layers is t2, the interface temperature between the middle and outer layers is t3, and the surface temperature of the tooling's outer layer is t4. The heat flux density between the inner and middle layers is q1 = α1(t1-t2), and the heat flux density between the middle and outer layers is... The heat flux density between the air and the outer layer is q3 = α0(t4 - t0), where q1 = q2 = q3. We can obtain the following: The value of the outer surface temperature of the tooling at the instant when the casting liquid solidifies to reach the solidus line is t4.

[0027] Furthermore, according to the temperature differences between the temperature values calculated theoretically and the temperature values at each temperature measurement point, as well as the temperature differences between the temperature measurement points at the casting center, determine the working modes of each heating device, including:

[0028] When T1≥t + f °C, let ΔT i ,

[0029] , i , 2i , 45 , 24 ,

[0031] , 3i ,

[0030] , i , 35 , , 34 , 45 , 2i , i , i , i , 25 , 3i , 23 , , = T2 - T1; ΔT 13 = T3 - T1; ΔT 14 = T4 - T1; ΔT 15 = T5 - T1. If ΔT 1i <0 °C, the i-th group of heating devices at the T j point works to heat the T i point. If ΔT 1i ≥0 °C, the i-th group of heating devices at the T i point does not work; when T1 < t + f °C, the first group of heating devices finishes working and its corresponding power device is turned off; t is the temperature value calculated theoretically; T i is the temperature value at each temperature measurement point; f is the error constant between the temperature calculated theoretically and the simulated temperature;

[0029] When T2≥t + f °C, let ΔT 23 = T3 - T2; ΔT <00000​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​When the temperature is <0℃, the fifth heating device at point T5 operates to heat point T5. If ΔT 4i ≥0℃, the fifth heating device at point T5 does not operate; when T4 < t + f℃, the operation of the fourth heating device ends, and its corresponding power device is turned off;

[0032] when T5 < t + f℃, the operation of the fifth heating device ends, and its corresponding power device is turned off; when the heating of the entire device ends, the main power supply is turned off.

[0033] Further, the output power of each heating device is determined, including: the output power of the heating device is where s is the heating time, and Q c is the heat released by the heating device.

[0034] Due to the adoption of the above technical solution, the technical progress achieved by the present invention is:

[0035] 1. The device of the present invention has multiple heating devices, which can be moved for heating within a movable range, and can quickly reach the set temperature value of the heated part of the workpiece to be heated, ensuring the sequential condensation of each part during the roll casting process. The device of the present invention has an infrared camera temperature measurement device, which can monitor the temperature value of the outer surface of the tooling in real time and send it to the central control console, so as to realize the adjustment and control of the temperature and ensure the accuracy of temperature control during the roll casting process.

[0036] 2. The method of the present invention establishes the temperature value relationship between the outer surface temperature value of the composite roll casting tooling and the temperature value at the casting center, obtains the outer surface temperature value of the composite roll casting tooling at the instantaneous moment when the casting liquid solidifies to reach the solidus line, calculates in real time the temperature difference between the temperature measurement points on the outer surface of the composite roll casting tooling and the temperature difference between the outer surface temperature value of the tooling at the instantaneous moment when the casting liquid solidifies to reach the solidus line and the outer surface temperature value actually collected by the infrared camera temperature measurement device, and controls the heating device to heat, so as to adjust the temperature of each part of the roll in real time and realize the sequential solidification during the composite roll casting process. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0038] Figure 1 is a schematic diagram of the device structure in an embodiment of the present invention;

[0039] Figure 2 is a sectional view of the device structure in an embodiment of the present invention;

[0040] Figure 3 This is a top half-sectional view of the device structure in an embodiment of the present invention;

[0041] Figure 4 This is a schematic diagram of the heating device structure in an embodiment of the present invention;

[0042] Figure 5 This is a schematic diagram of the power unit structure in an embodiment of the present invention;

[0043] Figure 6 This is a schematic diagram of the composite roll casting 1 / 2 structure in an embodiment of the present invention;

[0044] Figure 7 This is a cloud diagram of the cooling temperature field of the rolls in an embodiment of the present invention;

[0045] Figure 8 This is flowchart I of the heating method in an embodiment of the present invention;

[0046] Figure 9 This is flowchart II of the heating method in an embodiment of the present invention;

[0047] In the diagram, 1. Casting riser; 2. Upper sand box; 3. Roller mold; 4. Power unit; 5. Lower sand box; 6. Guide rail; 7. Fixed base; 8. First infrared camera temperature measuring device; 9. First heating device; 10. Second infrared camera temperature measuring device; 11. Second heating device; 12. Sliding block; 13. Third heating device; 14. Third infrared camera temperature measuring device; 15. Fourth heating device; 16. Fourth infrared camera temperature measuring device; 17. Fifth heating device; 18. Fifth infrared camera temperature measuring device; 19. Main power supply; 20. Balance ring; 41. Power unit housing; 42. Upper fixing frame of power unit; 43. Left fixing frame of power unit; 44. Motor; 45. Right fixing frame of power unit; 46. Lower fixing frame of power unit. Detailed Implementation

[0048] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0049] like Figure 1-3 As shown, this embodiment of the invention provides a heating device for shrinkage cavity in composite roll casting, including a central control console, five sets of temperature measuring and heating devices, a lifting device, a balance ring 20, a fixed base 7, and a main power supply 19. Wherein:

[0050] The fixed base 7 is fixedly connected to the base of the composite roll casting fixture.

[0051] The balance ring 20 is located at the top of the composite roll casting fixture, at the location of the casting riser 1.

[0052] The lifting device includes a guide rail 6 and a slider 12; the guide rail 6 is vertically arranged between the fixed base 7 and the balance ring 20; the slider 12 is connected to the guide rail 6 by a rolling element, and the slider 12 can move up and down on the guide rail 6.

[0053] The temperature measuring and heating device includes an infrared camera temperature measuring device, a heating device, and a power device; multiple infrared camera temperature measuring devices are arranged and fixed on the composite roll casting fixture from bottom to top in the order of gradually reaching the solidification line in the composite roll casting process; the infrared camera temperature measuring devices are connected to the central control console for data communication; in specific implementation, data communication can be achieved through wire connection or wireless connection.

[0054] Multiple heating devices are connected to the guide rail 6 sequentially from bottom to top through sliders 12, following the order in which the composite roll casting gradually reaches the solidus line. The number of sliders 12 is the same as the number of heating devices, and each heating device is connected to the guide rail 6 through one slider 12. The heating devices can move up and down along the guide rail 6. The power unit 4 is fixed together with the heating devices and has an electrical connection. The power unit 4 is connected to the main power supply 19 through a wire. The main power supply 19 is connected to the central control console through a wire.

[0055] The temperature measuring and heating device and the guide rail 6 form a hollow frame structure, which is fitted onto the outside of the composite roll casting fixture.

[0056] In specific implementation, two guide rails 6 can be used, with the slider 12 arranged on the first guide rail 6 and the power device 4 arranged on the second guide rail 6. One end of the contour heating coil is fixedly connected to the slider 12 by bolts, and the other end is fixedly connected to the power device 4 by bolts, forming a hollow frame structure. This structure is fitted onto the outside of the composite roll casting fixture. Multiple temperature measuring and heating devices arranged from bottom to top in the order of the composite roll casting gradually reaching the solidus line can be moved to adjust the temperature at each position.

[0057] In one specific embodiment, five sets of temperature measuring and heating devices can be used. These five sets are arranged sequentially from bottom to top according to the order in which the composite roll casting gradually reaches the solidification line: the first set of temperature measuring and heating devices, the second set of temperature measuring and heating devices, the third set of temperature measuring and heating devices, the fourth set of temperature measuring and heating devices, and the fifth set of temperature measuring and heating devices, and are distributed in parallel. The first set of temperature measuring and heating devices is connected to the guide rail 6. The first set of temperature measuring and heating devices is connected to the upper part of the lower sand box 5, the second set of temperature measuring and heating devices is connected to the middle of the groove on the lower side of the roll mold 3, the third set of temperature measuring and heating devices is connected to the middle of the roll mold 3, the fourth set of temperature measuring and heating devices is connected to the middle of the groove on the upper side of the middle of the roll mold 3, and the fifth set of temperature measuring and heating devices is connected to the middle of the upper sand box 2.

[0058] like Figure 4 As shown, the first set of temperature measuring and heating devices includes: a first infrared camera temperature measuring device 8, a first heating device 9, and a first power device 4. The first infrared camera temperature measuring device 8 includes: an infrared camera thermometer and a mounting base. The infrared camera thermometer is fixedly connected to the composite roll casting fixture via the mounting base.

[0059] The first heating device 9 includes: a contour heating coil and a heating coil mounting bracket; the heating coil is fixed on the heating coil mounting bracket, one end of the heating coil mounting bracket is fixedly connected to the slider 12 of the guide rail 6, and the other end is fixedly connected to the housing 41 of the power device. The positive and negative poles of the heating coil are connected to the motor 44, the output end of the motor 44 is fixed on the guide rail 6, and the terminal is connected to the main power supply 19.

[0060] like Figure 5 As shown, the first power unit 4 includes: an upper fixing frame 42, a lower fixing frame 46, a left fixing frame 43, and a right fixing frame 45, a motor 44, and a housing 41. The motor 44 is fixed inside the housing 41 via the upper fixing frame 42, the lower fixing frame 46, the left fixing frame 43, and the right fixing frame 45. The housing 41 is movably connected to the guide rail 6 via rolling elements such as balls. The power unit 4 can move up and down on the guide rail 6 simultaneously with the slider 12 at the corresponding position on the other guide rail 6.

[0061] The components and assembly relationships of the second, third, fourth, and fifth temperature measuring and heating devices are the same as those of the first group. Specifically, the second group includes: a second infrared camera temperature measuring device 10, a second heating device 11, and a second power device 4. The third group includes: a third infrared camera temperature measuring device 14, a third heating device 13, and a third power device 4. The fourth group includes: a fourth infrared camera temperature measuring device 16, a fourth heating device 15, and a fourth power device 4. The fifth group includes: a fifth infrared camera temperature measuring device 18, a fifth heating device 17, and a fifth power device 4.

[0062] The first, second, third, fourth, and fifth heating devices can move up and down on the guide rail 6 via slider 12, and each heating device has a movable range.

[0063] In the composite roll casting shrinkage cavity heating device described in the above embodiments, multiple sets of heating devices can move and heat within a movable range, controlling the heated part of the workpiece to quickly reach the set temperature value, ensuring the sequential condensation of each part during the roll casting process. An infrared camera temperature measurement device can monitor the temperature value of the outer surface of the tooling in real time and send it to the central control console, thereby achieving temperature regulation and control, ensuring the accuracy of temperature control during the roll casting process.

[0064] like Figure 8 As shown, the method for heating using the composite roll casting shrinkage cavity heating device in the above embodiment specifically includes the following steps:

[0065] S1. Power on, multiple heating devices reset and connected to the main power supply, ready for operation.

[0066] S2. The infrared temperature measurement camera device collects the temperature values ​​of each temperature measurement point on the outer surface of the composite roll casting fixture and sends them to the central control console in the form of mathematical signals.

[0067] The first infrared temperature measuring camera (T1) corresponds to the temperature measuring point of the first group of heating devices, the second infrared temperature measuring camera (T2) corresponds to the temperature measuring point of the second group of heating devices, the third infrared temperature measuring camera (T3) corresponds to the temperature measuring point of the third group of heating devices, the fourth infrared temperature measuring camera (T4) corresponds to the temperature measuring point of the fourth group of heating devices, and the fifth infrared temperature measuring camera (T5) corresponds to the temperature measuring point of the fifth group of heating devices.

[0068] S3, such as Figure 6As shown, the central control console calculates the surface temperature of the outer layer of the composite roll casting fixture at the instant the molten casting reaches the solidification line: Composite roll casting can be divided into three parts: upper, middle, and lower. The upper part is the upper sand box, which consists of three layers of material from the inside out. The inner layer ( Figure 6 -a), set the radius to r1, intermediate layer ( Figure 6 -b), with a thickness of x1, thermal conductivity of λ1, inner and middle layers being metal-sand, convective heat transfer coefficient of α1, and outer layer ( Figure 6 -c), with a thickness of x2, thermal conductivity of λ2, an outer layer and working environment of metal-air, convective heat transfer coefficient of α0, a foundry room temperature of t0, a casting liquid solidification temperature reaching the solidus line of t1, an interface temperature between the inner and middle layers of t2, an interface temperature between the middle and outer layers of t3, a tooling outer surface temperature of t4, a heat flux density between the inner and middle layers of q1 = α1(t1-t2), and a heat flux density between the middle and outer layers of q1 = α1(t1-t2). The heat flux density between the air and the outer layer is q3 = α0(t4 - t0), where q1 = q2 = q3. We can obtain the following: t4 is the temperature of the outer surface of the tooling at the instant when the molten casting reaches the solidification line. For ease of calculation, t4 will be denoted as t.

[0069] The calculation steps for the middle part are the same as those for the upper part, the difference being that the thickness parameters of the three layers of material are different, the inner layer ( Figure 6 -a'), sets the radius to r1', intermediate layer ( Figure 6 -b'), with a thickness of y1, thermal conductivity of η1, inner and middle layers made of metal-sand, convective heat transfer coefficient of α1, and outer layer ( Figure 6 -c'), with thickness set to y2, thermal conductivity to η2, outer layer and working environment as metal-air, convective heat transfer coefficient to α0, foundry room temperature to t0, instantaneous temperature at which the casting liquid solidifies to the solidus line to t1, interface temperature between inner and middle layers to t2, interface temperature between middle and outer layers to t3, outer surface temperature of tooling to t4, heat flux density between inner and middle layers to q1=α1(t1-t2), and heat flux density between middle and outer layers to q1=α1(t1-t2). The heat flux density between the air and the outer layer is q3 = α0(t4 - t0), where q1 = q2 = q3. We can obtain the following: t4 is the temperature of the outer surface of the tooling at the instant when the molten casting reaches the solidification line. For ease of calculation, t4 will be denoted as t.

[0070] The lower part is the sand box section, which has the same structure, calculation steps, and calculation parameters as the upper part.

[0071] S4, such as Figure 7As shown in the figure, simulate the casting and cooling process of the composite roll, and extract the temperature field nephograms of each temperature measurement point on the roll at each time stage.

[0072] S5. Establish a database, divide the outer surface of the composite roll casting tooling radially into n segments for trimming. When trimming the i-th segment, compare the temperature values calculated theoretically in S3 with the temperature values of the roll cooling and solidifying simulated in S4 to determine the error constant f between the theoretically calculated temperature and the actual simulated temperature. i is an integer from 0 to n, and store the comparison result f each time in the database to improve the accuracy of the corrected error constant f.

[0073] S6. As Figure 9 shown, the central console determines according to the actual temperature value T of the outer surface of the tooling at the acquisition moment i : (1) The temperature difference between t and T i ; (2) The temperature difference between each temperature measurement point at the casting center;

[0074] When T1≥t + f °C, let ΔT 12 = T2 - T1; ΔT 13 = T3 - T1; ΔT 14 = T4 - T1; ΔT 15 = T5 - T1. If ΔT 1i <0 °C, the i-th group of heating devices at the T i point works to heat the T i point. If ΔT 1i ≥0 °C, the i-th group of heating devices at the T i point does not work. When T1 < t + f °C, the first group of heating devices finishes working and its corresponding power device is turned off.

[0075] When T2≥t + f °C, let ΔT 23 = T3 - T2; ΔT 24 = T4 - T2; ΔT 25 = T5 - T2. If ΔT 2i <0 °C, the i-th group of heating devices at the T i point works to heat the T i point. If ΔT 2i ≥0 °C, the i-th group of heating devices at the T i point does not work. When T2 < t + f °C, the second group of heating devices finishes working and its corresponding power device is turned off.

[0076] When T3≥t + f °C, let ΔT 34 = T4 - T3; ΔT 35 = T5 - T3. If ΔT 3i <0 °C, the i-th group of heating devices at the T i point works to heat the T i point. If ΔT 3iWhen T≥0℃ i The i-th group of heating devices does not work. When T3 < t + f℃, the third group of heating devices finishes working, and its corresponding power device is turned off.

[0077] When T4≥t + f℃, let ΔT 45 = T5 - T4. If ΔT 45 <0℃, the fifth group of heating devices at the T5 point works to heat the T5 point. If ΔT 4i ≥0℃, the fifth group of heating devices at the T5 point does not work. When T4 < t + f℃, the fourth group of heating devices finishes working, and its corresponding power device is turned off.

[0078] When T5 < t + f℃, the fifth group of heating devices finishes working, and its corresponding power device is turned off. When the heating of the entire device is completed, the main power supply is turned off.

[0079] S7. Determine the output power of the heating devices. Denote the temperature measured by the i-th temperature measuring device as T i , the ideal temperature of the i-th as T i ', the temperature measured by the j-th temperature measuring device as T j , and always have T i '≥T j (i > j). Set the specific heat of the substance as C, the mass of the object as m, and the heat absorbed by the heated workpiece as Q = Cm(T i ' - T i ). The heat released by the heating device is Q c , Q c ≥Q. Set the heating time as s, and the output power of the heating device is

[0080] S8. After calculation by the central control console, it feeds back to the heating devices at each point to control the heating. The five groups of heating devices can move and heat within the movable range, with a moving angular velocity of 10 mm / s and an output power of P.

[0081] [[ID=4,2]]According to the composite roll casting shrinkage porosity heating method in the above embodiment, by establishing the temperature value relationship between the outer surface temperature value of the composite roll casting tooling and the pouring center temperature value, obtaining the outer surface temperature value of the composite roll casting tooling at the instantaneous moment when the casting liquid pouring and solidification reach the solidus line, calculating in real time the temperature difference between the temperature measuring points on the outer surface of the composite roll casting tooling and the temperature difference between the outer surface temperature value of the tooling at the instantaneous moment when the casting liquid pouring and solidification reach the solidus line and the outer surface temperature value of the tooling actually collected by the infrared camera temperature measuring device, and controlling the heating device to heat, it can adjust the temperature of each part of the roll in real time and achieve sequential solidification during the composite roll casting process.

[0082] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method of heating by means of a composite roll casting porosity and shrinkage heating device, characterized in that, The composite roller casting porosity and shrinkage heating device comprises a center console, multiple sets of temperature measuring and heating devices, a lifting device, a gimbal (20), a fixed base (7) and a total power supply (19); The fixed base (7) is fixedly connected to the base of the composite roller casting tooling; the gimbal (20) is located at the top of the composite roller casting tooling; The lifting device comprises a guide rail (6) and a sliding block (12); the guide rail (6) is vertically arranged between the fixed base (7) and the gimbal (20); the sliding block (12) is rollingly connected with the guide rail (6) through a rolling element, and the sliding block (12) can move up and down on the guide rail (6); The temperature measuring and heating device comprises an infrared camera temperature measuring device, a heating device and a power device (4); multiple infrared camera temperature measuring devices are sequentially arranged and fixed on the composite roller casting tooling from bottom to top according to the order of gradually reaching the solidification line during the composite roller casting, and the infrared camera temperature measuring device is in data communication connection with the center console; multiple heating devices are sequentially connected with the guide rail (6) through the sliding block (12) from bottom to top according to the order of gradually reaching the solidification line during the composite roller casting; the heating device can move up and down along the guide rail (6); the power device (4) is fixed with the heating device and has an electrical connection; the power device (4) is connected with the total power supply (19) through a wire; the total power supply (19) is connected with the center console through a wire; Multiple heating devices and the guide rail (6) form a hollow frame structure and are sleeved outside the composite roller casting tooling; The method comprises: Power on, multiple sets of temperature measuring and heating devices reset and turn on the total power supply, and preparation work is performed; The infrared temperature measuring camera device collects temperature values of each temperature measuring point on the outer surface of the composite roller casting tooling and sends the temperature values to the center console in the form of mathematical signals; the center console calculates the temperature value of the outer surface of the composite roller casting tooling at the moment when the casting liquid casting solidification reaches the solidification line to obtain a theoretically calculated temperature value; An analog composite roller casting and cooling process is simulated, a temperature field cloud picture of each temperature measuring point of the roller at each time stage is extracted, and a simulated temperature value is obtained; A database is established, and the outer surface of the composite roll casting tool is radially divided into n segments for finishing i When finishing the segments, the theoretically calculated temperature value is compared with the simulated temperature value to determine an error constant of the theoretically calculated temperature and the simulated temperature, and the error constant obtained from each comparison is stored in the database. i is an integer from 0 to n; The center console determines the temperature difference between the theoretically calculated temperature value and the temperature value of each temperature measuring point and the temperature difference between each temperature measuring point at the casting center, and determines the working mode of each heating device according to the temperature difference between the theoretically calculated temperature value and the temperature value of each temperature measuring point and the temperature difference between each temperature measuring point at the casting center; The output power of each heating device is determined; The center console feeds back the output power of each heating device to each heating device to control heating, and each heating device moves in the movable range to heat.

2. The method of claim 1, wherein, The temperature measuring and heating device is five sets.

3. The method of claim 2, wherein, The first set of temperature measuring and heating devices is located at the upper middle part of the lower sand box (5), the second set of temperature measuring and heating devices is located at the middle part of the lower side groove of the roller mold (3), the third set of temperature measuring and heating devices is located at the middle part of the roller mold (3), the fourth set of temperature measuring and heating devices is located at the middle part of the upper side groove of the roller mold (3), and the fifth set of temperature measuring and heating devices is located at the middle part of the upper sand box (2).

4. The method of claim 1, wherein, The infrared camera temperature measuring device comprises an infrared camera temperature measuring instrument and a fixing seat for fixing the infrared camera temperature measuring instrument.

5. The method of claim 1, wherein, The heating device comprises a profiled heating coil and a heating coil fixing frame for fixing the profiled heating coil; one end of the heating coil fixing frame is fixedly connected to the guide rail (6) sliding block (12), and the other end is fixedly connected to the power device (4).

6. The method of claim 5, wherein, The power device (4) comprises a motor (44), a power device shell (41), a power device upper fixing frame (42), a power device lower fixing frame (46), a power device left fixing frame (43) and a power device right fixing frame (45); the profiled heating coil positive and negative electrodes are connected to the motor (44), and the motor (44) is connected to the total power supply (19); the motor (44) is fixed in the power device shell (41) through the power device upper fixing frame (42), the power device lower fixing frame (46), the power device left fixing frame (43) and the power device right fixing frame (45); the power device shell (41) is rollingly connected to the guide rail (6) through rolling elements; and the power device (4) can move up and down on the guide rail (6).

7. The method of claim 6, wherein, The center console calculates the temperature value of the outer surface of the composite roller casting tool at the moment when the casting liquid casting solidification reaches the solidus, obtains a theoretically calculated temperature value, and comprises: The composite roller casting is divided into upper, middle and lower parts, and each part is: The three layers are from inside to outside, the inner layer has a radius of r 1, the middle layer has a thickness of x 1, and a thermal conductivity of According to the temperature difference between the theoretically calculated temperature value and the temperature value of each temperature measuring point and the temperature difference between each temperature measuring point at the casting center, the working mode of each heating device is determined, and comprises: 1, the inner layer and the middle layer are metal and sand, and a convective heat transfer coefficient of α 1, the outer layer has a thickness of x 2, a thermal conductivity of ​ 2, and the outer layer and the working environment are metal and air, and a convective heat transfer coefficient of α 0; the room temperature of the foundry workshop is set to t 0, the temperature of the casting liquid at the moment when the casting solidifies to the solidus is t 1, the interface temperature between the inner layer and the middle layer is t 2, the interface temperature between the middle layer and the outer layer is t 3, the surface temperature value of the outer layer of the tooling is t 4, the heat flux density between the inner layer and the middle layer is , the heat flux density between the middle layer and the outer layer is , and the heat flux density between the air and the outer layer is , wherein , and the following is obtained: , t 4 is the surface temperature value of the outer layer of the tooling at the moment when the casting liquid solidifies to the solidus.

8. The method of claim 6, wherein, ​ when T 1 ≥ t + f ℃, making ; ; ; ,like At < 0℃, T j Point 1 i The heating device is working, heating T i Point, if At ≥ 0℃, T i Point 1 i The heating unit is not working; when T 1< t + f At ℃, the first group of heating devices has finished working and its corresponding power device is turned off; t The temperature value calculated according to the theory; T i The temperature values ​​at each of the aforementioned temperature measurement points; f The error constant between the theoretically calculated temperature and the simulated temperature; when T 2≥ t + f ℃, making ; ; ,like At < 0℃, T i Point 1 i The heating device is working, heating T i Point, if At ≥ 0℃, T i Point 1 i The heating unit is not working; when T 2< t + f At ℃, the second group of heating devices has finished working and its corresponding power device is turned off; when T 3≥ t + f ℃, making ; ,like At < 0℃, T i Point 1 i The heating device is working, heating T i Point, if At ≥ 0℃, T i Point 1 i The heating unit is not working; when T 3 < t + f At ℃, the third heating device finishes its operation and its corresponding power device is turned off; When T 4≥ t + f ℃, let , if < 0℃, T 5 points the fifth group of heating device work, heating T 5 points, if ≥ 0℃, T 5 points the fifth group of heating device does not work; when T 4 < t + f ℃, the fourth group of heating device work is finished, and the corresponding power device is closed. When T 5 < t + f °C, the fifth group of heating devices stops working, and the corresponding power device is turned off; the whole device stops heating, and the total power supply is turned off.

9. The method of claim 6, wherein, Determining the output power of each heating device, including: the heating device output power is where s is the heating time, Q c Releasing heat for the heating device.

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