A partitioned thermal field regulating device and method for directional solidification of turbine blades

Abstract

This application relates to the field of turbine blade casting technology, specifically to a zoned thermal field control device and method for directional solidification of turbine blades. By setting an insulated chassis between the hot and cold chambers of the directional solidification furnace, and arranging independently expandable and contractile heat-conducting cores in a honeycomb array in the insulated chassis, the control system performs thermal field adjustment of different sections of the blade according to the characteristics of different parts of the turbine blade based on the target expansion and contraction position curve and the heating power curve, thereby realizing zoned dynamic thermal field control and improving the yield of turbine blades.

Description

Technical Field

[0001] This application relates to the field of turbine blade casting technology, specifically to a zoned thermal field control device and method for directional solidification of turbine blades. Background Technology

[0002] Directional solidification is a key process in the manufacture of single-crystal / column-crystal hollow turbine blades. In a directional solidification furnace, the molten metal solidifies sequentially from bottom to top through the temperature gradient between the heating chamber (approximately 1500~1600℃) and the cooling chamber, achieving ideal grain orientation. Turbine blades have a complex variable cross-section structure: the blade body has thin walls (1-2mm), while the rim and tenon sections are thick (up to 10mm or more). During directional solidification, the thin-walled sections dissipate heat quickly and have a large temperature gradient, while the thick sections dissipate heat slowly and have insufficient supercooling, making them highly susceptible to metallurgical defects such as impurities and freckles.

[0003] In existing technologies, CN103192063A only uses a simple fixed heat insulation plate between the hot and cold chambers. Temperature field control is limited, and the baffles are uniform, making it unable to adapt to changes in the outer contour of the casting. When large cross-sections such as the rim plate pass through, the gap is too large, reducing heat exchange efficiency; when slender cross-sections such as the blade body pass through, the gap is too small, potentially causing interference. Rapid localized heat dissipation at abrupt changes in cross-section, such as the rim plate and blade crown, leads to disordered temperature gradients and easily forms impurity crystal defects.

[0004] Therefore, this application is submitted. Summary of the Invention

[0005] This invention provides a zoned thermal field control device and method for directional solidification of turbine blades. By setting an insulated chassis between the hot and cold chambers of the directional solidification furnace, and arranging independently expandable and contractile heat-conducting cores in a honeycomb array in the insulated chassis, the control system, based on the target expansion and contraction position curve and heating power curve, and according to the characteristics of different parts of the turbine blade, executes thermal field adjustment for different sections of the blade, realizing zoned dynamic thermal field control, improving the yield of turbine blades, and solving the problems existing in the prior art.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following solution: A zoned thermal field control device for directional solidification of turbine blades, comprising: A heat-insulating base is horizontally positioned between the hot chamber and the cold chamber of a directional solidification furnace. The heat-insulating base has multiple through-holes arranged in a honeycomb pattern. The heat-insulating base has independent cooling channels that are isolated from the through-holes. Cooling medium is introduced into the independent cooling channels. Each mounting hole contains a heat-conducting core that can extend and retract independently in the vertical direction; Multiple hydraulic cylinders are installed under the heat-insulating chassis. Each hydraulic cylinder drives a heat-conducting core, and the bottom end of the heat-conducting core is connected to the output end of the hydraulic cylinder. The control system is electrically connected to the control valves of multiple hydraulic cylinders to control the extension and retraction position of each heat-conducting core.

[0007] Furthermore, the heat-conducting core is made of graphite material, and its axial height is less than the thickness of the heat-insulating chassis; the upper end face and outer peripheral sidewall of the heat-conducting core are coated with radiation-absorbing coatings, and its lower end face is coated with a heat-insulating protective layer.

[0008] Furthermore, the upper surface of the heat-conducting core faces the heat chamber and is provided with an insulating sleeve on its outer periphery.

[0009] Furthermore, the interior of the heat-conducting core is equipped with a graphite heating rod that is electrically connected to the control system.

[0010] Furthermore, the heat-insulating chassis is made of heat-resistant steel or nickel-based high-temperature alloy, and its surface is provided with a heat-protective coating.

[0011] Furthermore, the independent cooling channel has a serpentine coil structure, and the cooling medium is either argon or nitrogen.

[0012] Furthermore, a displacement sensor is installed inside the hydraulic cylinder to provide real-time feedback on the extension and retraction position of the heat-conducting core.

[0013] Furthermore, a non-contact temperature sensor is installed on the upper side of the heat-conducting core to monitor the gap temperature field between the heat-conducting core and the casting shell in real time.

[0014] A method for controlling the zoned thermal field in the directional solidification of turbine blades, employing the aforementioned device for controlling the zoned thermal field in the directional solidification of turbine blades, includes the following steps: S1: Construct a casting digital model, slice the three-dimensional digital model of the turbine blade casting along the pulling direction, extract the outer contour data of each slice, and generate the target expansion and contraction position curve and heating power curve of each heat-conducting core throughout the pulling process. S2: Install the heat-insulating chassis between the hot and cold chambers of the directional solidification furnace, align the center of the heat-insulating chassis with the center of the casting, pre-adjust each heat-conducting core to its initial position, inject cooling medium into the independent cooling channels of the heat-insulating chassis and start the circulation. S3: Start the pull-out process. The control system reads the pull-out position of the shell in real time at the horizontal plane where the upper surface of the heat insulation chassis is located. According to the target extension and retraction position curve, the control system drives the corresponding heat-conducting core to extend and retract, so that the outer wall of each heat-conducting core and the outer wall of the shell of the turbine blade casting maintain a preset lateral gap. S4: Based on the characteristics of different parts of the turbine blades, the control system performs zoned adjustment, controlling the extension and retraction position of the heat-conducting core in the corresponding area and the power of the built-in graphite heating rod.

[0015] Furthermore, the partition adjustment in step S4 includes: When the blade section of the casting passes through, the corresponding heat-conducting core is controlled to be in cooling mode, so that its outer wall and the shell maintain a lateral gap L1, the graphite heating rod is turned off, and the heat-conducting core is used to guide the heat of the shell to the cold chamber. When the thick edge plate or tenon of the casting passes through, the heat-conducting core in the corresponding area is controlled to be in heating mode, so that its outer wall and the shell maintain a lateral gap L2. The graphite heating rod is turned on and the power is adjusted to radiate heat to the shell to suppress the nucleation of impurity crystals. When the transition section of the casting passes through, the corresponding area of ​​the heat-conducting core is controlled to be in the heat insulation buffer mode, so that the lower end face of the heat-conducting core retracts into the heat insulation chassis and the heat insulation protection layer of the lower end face blocks the heat conduction.

[0016] The beneficial effects of this invention are as follows: This invention achieves zoned thermal field control of different regions of turbine blades, including the blade body, rim plate, and transition zone, by arranging independently telescopic heat-conducting cores in a honeycomb array within a heat-insulated chassis and based on the three working modes of the heat-conducting cores. This improves the heat dissipation efficiency of thinner parts of the blade, suppresses impurity crystal defects in thicker parts of the blade, and increases the yield of single-crystal blades.

[0017] The heat-conducting core is equipped with a heatable graphite heating rod, which not only guides heat to the cold chamber through the high thermal conductivity of graphite, but also actively radiates heat to the shell, thus realizing bidirectional regulation of the local thermal field.

[0018] The axial height of the heat-conducting core is less than the thickness of the heat-insulating chassis. When in the heat insulation buffer mode, the heat-conducting core can be completely retracted into the chassis. The heat insulation protection layer on the lower end face effectively blocks the heat flow in the transition section, effectively reduces thermal stress, and prevents thermal cracks from occurring at the R-corner. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the partitioned thermal field control device of the present invention; Figure 2 This is a schematic diagram of the structure of the heat-conducting core of the present invention; Figure 3 This is a top-section structural diagram of the heat-insulating chassis of the present invention; Figure 4 This is a schematic diagram of the workflow of the partitioned thermal field control method of the present invention.

[0020] Reference numerals: 1-Hot chamber, 2-Cold chamber, 3-Insulated chassis, 30-Mounting through hole, 31-Independent cooling channel, 4-Heat-conducting core, 40-Radiation absorbing coating, 41-Insulation protective layer, 42-Insulation sleeve, 43-Graphite heating rod, 5-Hydraulic cylinder, 6-Shell. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0022] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of the invention.

[0023] At the same time, it should be understood that, for ease of description, the dimensions of the various parts shown in the accompanying drawings are not drawn according to actual scale.

[0024] Furthermore, for clarity and brevity, descriptions of well-known structures, functions, and configurations may have been omitted. Those skilled in the art will recognize that various changes and modifications can be made to the examples described herein without departing from the spirit and scope of this disclosure.

[0025] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0026] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0027] Example 1 A zoned thermal field control device for directional solidification of turbine blades, comprising: A heat-insulating base 3 is horizontally set between the hot chamber 1 and the cold chamber 2 of the directional solidification furnace. The heat-insulating base 3 has multiple through-holes 30 arranged in a honeycomb pattern. The heat-insulating base 3 has an independent cooling channel 31 that is isolated from the installation through-holes 30. A cooling medium is introduced into the independent cooling channel 31. Each mounting through hole 30 contains a heat-conducting core 4 that can extend and retract independently in the vertical direction; Multiple hydraulic cylinders 5 are installed below the heat-insulating chassis 3. Each hydraulic cylinder 5 drives a heat-conducting core 4. The bottom end of the heat-conducting core 4 is connected to the output end of the hydraulic cylinder 5. The control system is electrically connected to the control valves of multiple hydraulic cylinders 5 to control the extension and retraction position of each heat-conducting core 4.

[0028] Reference Figure 1 The technical concept of this invention is to set up an insulated chassis 3 between the cold chamber 2 and the hot chamber 1 of a directional solidification furnace, and an independently telescopic heat-conducting core 4 located within the mounting through-hole 30 of the insulated chassis 3. The heat-conducting core 4 cooperates with the cooling medium in the independent cooling channel 31 within the insulated chassis 3. The telescopic state of the hydraulic cylinder 5 changes the correspondence between the heat-conducting core 4 and each blade section within the casting, thereby regulating the thermal field requirements of each blade section. Specifically, for the blade body section, heat needs to be discharged to establish the maximum axial gradient, accelerate directional growth, and avoid grain coarsening and orientation deviation. For the rim plate section, heat needs to be compensated to reduce the local cooling rate, suppress non-uniform nucleation, and avoid impurities and freckles. For the transition section between the two, heat flow needs to be blocked to establish a smooth temperature field gradient and release thermal stress. This solves the problem of the prior art not performing thermal field zoning for each blade section.

[0029] In addition, the honeycomb arrangement refers to the arrangement of each mounting through hole 30 in a regular hexagonal pattern to maximize space utilization and thermal field control resolution. The specific specifications and quantity of the heat-conducting core 4 can be set according to the actual thermal field and the requirements of the casting shell 6.

[0030] It should be noted that the control system and hydraulic cylinder 5 are conventional technologies in this field and are existing technologies. Their specific specifications and principles in the directional solidification furnace will not be elaborated here.

[0031] In some preferred embodiments, reference is made to Figure 2 The heat-conducting core 4 is made of graphite material, and its axial height is less than the thickness of the heat-insulating chassis 3. For example, the chassis thickness is 80 mm and the core height is 60 mm. The upper end face and outer peripheral sidewall of the heat-conducting core 4 are coated with a radiation-absorbing coating 40, such as a silicon carbide coating, to enhance the absorption capacity of the radiant heat of the shell 6. Its lower end face is coated with a heat-insulating protective layer 41, such as a zirconium oxide thermal barrier coating, to block heat conduction in the insulation mode and improve the insulation effect of the transition section.

[0032] In some preferred embodiments, the upper end face of the heat-conducting core 4 faces the heat chamber 1 and is provided with an insulating sleeve 42 on its outer periphery. The insulating sleeve is made of ceramic fiber material, and its inner diameter is clearance-fitted with the heat-conducting core 4, and its outer diameter is clearance-fitted with the mounting through hole 30, which effectively reduces radial heat conduction between the heat-conducting core 4 and the heat-insulating chassis 3.

[0033] In some preferred embodiments, a graphite heating rod 43 electrically connected to the control system is provided inside the heat-conducting core 4. The graphite heating rod 43 is a heating element embedded inside the heat-conducting core 4. The lead wire of the graphite heating rod 43 is led out through the piston rod of the hydraulic cylinder 5 and electrically connected to the control system. The maximum operating temperature of the graphite heating rod 43 can reach 1800℃, which can meet the requirements for radiant heating of the shell 6.

[0034] In some preferred embodiments, reference is made to Figure 3 The heat-insulating chassis 3 is made of heat-resistant steel or nickel-based high-temperature alloy, and its surface is coated with a heat-protective coating. This ensures that the heat-insulating chassis 3 maintains rigidity, precision, and fatigue resistance at high temperatures, and guarantees a precise fit between the honeycomb mounting holes 30 and the heat-conducting core 4. The heat-protective coating includes a ceramic layer with low thermal conductivity that blocks heat flow; the two work together to resist high-temperature oxidation and thermal radiation during directional solidification.

[0035] In some preferred embodiments, the independent cooling channels 31 have a serpentine coil structure, and the cooling medium is either argon or nitrogen. The independent cooling channels 31 are evenly distributed within the heat-insulating chassis 3 in a serpentine coil structure, surrounding each mounting through-hole 30. Simultaneously, high-purity argon or nitrogen is introduced and forced to flow through an external circulation system, controlling the temperature of the heat-insulating chassis 3 within the range of 200~400℃. This is used to adjust the thermal field of different blade sections according to changes in the extension / retraction position and operating state of the heat-conducting core 4, ensuring its structural stability.

[0036] In some preferred embodiments, a displacement sensor is installed inside the hydraulic cylinder 5 to provide real-time feedback on the extension and retraction position of the heat-conducting core 4. A non-contact temperature sensor is installed on the upper side of the heat-conducting core 4 to monitor the temperature field of the gap between the heat-conducting core 4 and the cast shell 6 in real time. The measurement signals from the temperature sensor and the displacement sensor are fed back to the control system to control the heating power and extension / retraction position. The control system is electrically connected to the control valves, displacement sensors, temperature sensors, and power modules of the graphite heating rod 43 of the multiple hydraulic cylinders 5 to control the extension / retraction position and heating power of each heat-conducting core 4. This is prior art and will not be described in detail here.

[0037] Example 2 A method for controlling the zoned thermal field in the directional solidification of turbine blades, employing a zoned thermal field control device for the directional solidification of turbine blades as described in Example 1, includes the following steps: S1: Construct a casting digital model. Slice the three-dimensional digital model of the turbine blade casting along the pulling direction (Z-axis) at intervals of 0.1mm. Extract the outer contour data of each slice and calculate the wall thickness distribution and cross-sectional area change rate at each slice position. Simulate the directional solidification process under optimal thermal field control conditions using casting simulation software. Simulate and output the target expansion and contraction position curve Zi(t) and heating power curve Pi(t) of each heat-conducting core 4 throughout the pulling process, where i represents the number of the heat-conducting core 4 and t is the pulling time.

[0038] S2: Install the heat-insulating chassis 3 between the hot chamber 1 and the cold chamber 2 of the directional solidification furnace, and align the center of the heat-insulating chassis 3 with the center of the casting using positioning pins. Pre-adjust each heat-conducting core 4 to its initial position using the control system (usually the heat-conducting core 4 is retracted into the heat-insulating chassis 3). Inject cold high-purity argon gas into the independent cooling channel 31 of the heat-insulating chassis 3 and start the circulation to stabilize the temperature of the heat-insulating chassis 3 within the set range, such as 280~320℃.

[0039] S3: Initiate the pulling action. The casting (along with the shell 6) moves downwards at a set pulling speed (e.g., 3~6 mm / min). The control system reads in real time the pulling position S(t) of the shell 6 at the horizontal plane where the upper surface of the heat-insulating chassis 3 is located (feedback from the displacement encoder in the pulling mechanism). Based on the pulling position S(t), the control system finds the target extension / retraction position curve Zi(t) generated in step S1, and uses a PID algorithm to control the servo valve of each hydraulic cylinder 5, driving the corresponding heat-conducting core 4 to extend and retract, so that the outer wall of each heat-conducting core 4 maintains a preset lateral gap with the outer wall of the shell 6 of the turbine blade casting. At the same time, the temperature sensor monitors the gap temperature field in real time to correct the gap set value.

[0040] S4: Based on the characteristics of different parts of the turbine blades, the control system performs zoned adjustment, controlling the extension and retraction position of the corresponding heat-conducting core 4 and the power of the built-in graphite heating rod 43, as referenced. Figure 4 .

[0041] (1) Cooling mode (blade section) When the pull-out position enters the blade section, the control system determines that this section has thin walls and high heat dissipation requirements. It then controls the corresponding area's heat-conducting core 4 to enter cooling mode: maintaining a lateral gap L1 between the outer wall of the heat-conducting core 4 and the shell 6 (without generating mechanical pressure), and shutting off the built-in graphite heating rod 43. At this time, the heat from the shell 6 is absorbed by the outer wall of the heat-conducting core 4 through radiation, conducted downwards via the highly thermally conductive graphite heating rod 43, and directed by the heat-conducting core 4 to the cold chamber 2. Finally, the heat is carried away by argon gas in the independent cooling channel 31 of the insulated chassis 3, achieving forced cooling.

[0042] The heat-conducting core 4 efficiently directs the heat from the hot chamber 1 to the cold chamber 2, establishing a steep axial temperature gradient in the blade region, which is beneficial for the preferential growth of oriented grains.

[0043] (2) Heating mode (edge ​​plate / tenon section) When the pull-out position enters the thick part of the edge plate or tenon, the control system judges that the cross-section of this section changes abruptly and the heat dissipation is too fast, which may lead to the nucleation of impurity crystals. The corresponding heat-conducting core 4 is controlled to be in heating mode: its outer wall is kept at a lateral gap L2 with the shell 6, the built-in graphite heating rod 43 is turned on, and the power is adjusted according to the feedback of the temperature sensor to radiate heat to the shell 6.

[0044] The heat-conducting core 4 actively replenishes heat to the thick parts, counteracts the local overcooling caused by geometric abrupt changes, inhibits the nucleation and growth of impurity crystals, and ensures that the single crystal structure can pass smoothly through the edge plate area.

[0045] It should be noted that in the shell 6, the thick part of the flange or tenon is located on the convex part of the outer wall of the shell 6, and the blade section is located on the concave part of the outer wall of the shell 6. The heat insulation base 3 has a fixed inner diameter, which is slightly larger than the most convex part of the outer wall of the shell 6. Therefore, during the entire process of pulling the shell 6 downward, the concave part of the outer wall of the shell 6 always maintains a large lateral distance with the heat insulation base 3, so the lateral gap L1 is greater than the lateral gap L2.

[0046] (3) Thermal buffer mode (transition section) When the pull-out position enters the transition area (R-angle region) between the blade and the ferrule, the control system determines that this section is a stress concentration area, requiring avoidance of drastic changes in the thermal field. The corresponding area's heat-conducting core 4 is then placed in an adiabatic buffer mode: the heat-conducting core 4 retracts, its lower end face retracting into the heat-insulating chassis 3, utilizing the heat-insulating protective layer 41 on the lower end face to block heat conduction. Simultaneously, the outer periphery heat-insulating sleeve 42 of the heat-conducting core 4 further reduces radial heat flow.

[0047] The heat-conducting core 4 is no longer in contact with the shell 6, and the conduction path with the cold chamber 2 is cut off. This area is slowly cooled only by the natural heat insulation effect of the heat-insulating chassis 3, thus smoothing the transition from the high gradient cooling of the blade to the heat replenishment mode of the blade plate, effectively reducing thermal stress and preventing thermal cracks from forming at the R-corner.

[0048] Throughout the entire pulling process, the control system receives feedback signals in real time from a non-contact temperature sensor located on the upper end of the heat-conducting core 4. When the temperature difference between two adjacent heat-conducting cores 4 exceeds a preset threshold (e.g., 50°C), the control system dynamically adjusts the extension / retraction position or heating power of the corresponding core using a PID algorithm to eliminate sudden changes in lateral heat flow and ensure the uniformity of the heat field distribution.

[0049] In this invention, the PID algorithm and casting simulation software are used to simulate the expansion and contraction position curve Zi(t) and the heating power curve Pi(t), which are existing technologies and will not be described in detail here.

[0050] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A zoned thermal field control device for directional solidification of turbine blades, characterized in that, include: A heat-insulating base (3) is horizontally set between the hot chamber (1) and the cold chamber (2) of the directional solidification furnace. The heat-insulating base (3) has multiple through-holes (30) arranged in a honeycomb pattern. The heat-insulating base (3) has an independent cooling channel (31) isolated from the installation through-holes (30) inside. Cooling medium is introduced into the independent cooling channel (31). Each mounting through hole (30) contains a heat-conducting core (4) that can extend and retract independently in the vertical direction. Multiple hydraulic cylinders (5) are set below the heat-insulating chassis (3), and each hydraulic cylinder (5) drives a heat-conducting core (4). The bottom end of the heat-conducting core (4) is connected to the output end of the hydraulic cylinder (5). The control system is electrically connected to the control valves of multiple hydraulic cylinders (5) to control the extension and retraction position of each heat-conducting core (4).

2. The partitioned thermal field control device for directional solidification of turbine blades according to claim 1, characterized in that, The heat-conducting core (4) is made of graphite material and its axial height is less than the thickness of the heat-insulating chassis (3). The upper end face and outer peripheral sidewall of the heat-conducting core (4) are coated with radiation absorption coating (40) respectively, and its lower end face is coated with heat-insulating protective layer (41).

3. The zoned thermal field control device for directional solidification of turbine blades according to claim 1, characterized in that, The upper end face of the heat-conducting core (4) faces the heat chamber (1) and the outer periphery is provided with an insulating sleeve (42).

4. The zoned thermal field control device for directional solidification of turbine blades according to claim 2, characterized in that, The interior of the heat-conducting core (4) is provided with a graphite heating rod (43) that is electrically connected to the control system.

5. A zoned thermal field control device for directional solidification of turbine blades according to claim 2, characterized in that, The heat-insulated chassis (3) is made of heat-resistant steel or nickel-based high-temperature alloy, and its surface is provided with a heat-protective coating.

6. A zoned thermal field control device for directional solidification of turbine blades according to claim 2, characterized in that, The independent cooling channel (31) has a serpentine coil structure, and the cooling medium is either argon or nitrogen.

7. A zoned thermal field control device for directional solidification of turbine blades according to claim 2, characterized in that, A displacement sensor is installed inside the hydraulic cylinder (5) to provide real-time feedback on the extension and retraction position of the heat-conducting core (4).

8. A zoned thermal field control device for directional solidification of turbine blades according to claim 2, characterized in that, A non-contact temperature sensor is installed on the upper side of the heat-conducting core (4) to monitor the gap temperature field between the heat-conducting core (4) and the cast shell (6) in real time.

9. A method for controlling the zoned thermal field in the directional solidification of turbine blades, characterized in that, The turbine blade directional solidification zoned thermal field control device according to any one of claims 1 to 8 includes the following steps: S1: Construct a casting digital model, slice the three-dimensional digital model of the turbine blade casting along the pulling direction, extract the outer contour data of each slice, and generate the target extension and retraction position curve and heating power curve of each heat-conducting core (4) throughout the pulling process. S2: Install the heat insulation chassis (3) between the hot chamber (1) and the cold chamber (2) of the directional solidification furnace, and align the center of the heat insulation chassis (3) with the center of the casting. Pre-adjust each heat-conducting core (4) to the initial position, inject cooling medium into the independent cooling channel (31) of the heat insulation chassis (3) and start the circulation. S3: Start the pull-out, and the control system reads the pull-out position of the shell (6) in real time at the horizontal plane where the upper surface of the heat insulation chassis (3) is located. According to the target extension and retraction position curve, control each hydraulic cylinder (5) to drive the corresponding heat-conducting core (4) to extend and retract, so that the outer wall of each heat-conducting core (4) and the outer wall of the shell (6) of the turbine blade casting maintain a preset lateral gap. S4: Based on the characteristics of different parts of the turbine blade, the control system performs zoned adjustment to control the extension and retraction position of the corresponding heat-conducting core (4) and the power of the built-in graphite heating rod (43).

10. The method for controlling the zoned thermal field in the directional solidification of turbine blades according to claim 9, characterized in that, The partition adjustment in step S4 includes: When the blade section of the casting passes through, the heat-conducting core (4) in the corresponding area is controlled to be in cooling mode, so that its outer wall and the shell (6) maintain a lateral gap L1, the graphite heating rod (43) is turned off, and the heat of the shell (6) is directed to the cold chamber (2) by the heat-conducting core (4). When the thick edge plate or tenon of the casting passes through, the heat-conducting core (4) in the corresponding area is controlled to be in heating mode, so that its outer wall and the shell (6) maintain a lateral gap L2, the graphite heating rod (43) is turned on and the power is adjusted to radiate heat to the shell (6) to suppress the nucleation of impurity crystals. When the transition section of the casting passes through, the heat-conducting core (4) in the corresponding area is controlled to be in the heat insulation buffer mode, so that the lower end face of the heat-conducting core (4) retracts into the heat insulation chassis (3) and the heat conduction is blocked by the heat insulation protection layer (41) on the lower end face.

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