High-temperature synchronous micro hammer forging assisted large water turbine runner chamber inner wall additive repairing and remanufacturing system and method

Abstract

The invention provides a high-temperature synchronous micro-hammer forging assisted large water turbine runner chamber inner wall additive repairing and remanufacturing system and a high-temperature synchronous micro-hammer forging assisted large water turbine runner chamber inner wall additive repairing and remanufacturing method. A penetrant flaw detection module, a pretreatment milling and polishing back gouging module, a pretreatment area induction preheating and temperature control module, an additive deposition module, a micro hammer forging module, an annular rail carrying module, a post-treatment milling and polishing shaping module and other modularization are arranged, and various machining and control assemblies are arranged. A large water turbine runner chamber inner wall additive repairing and remanufacturing system and a high-temperature intermittent hammering deformation auxiliary additive repairing and remanufacturing characteristic process method are established, and high-temperature synchronous micro-hammer forging is introduced to assist large water turbine runner chamber inner wall additive repairing and remanufacturing. The structure state and the residual stress state of the runner chamber inner wall repair layer are regulated, the mechanical property of the repair layer is improved, and the service performance and the service life of large turbine runner chamber inner wall steel plates are prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of additive manufacturing, and in particular to a system and method for additively repairing and remanufacturing a runner chamber wall of a large-scale water turbine assisted by high-temperature synchronous micro-hammer forging. Background Art

[0002] The turbine runner chamber is the annular space where the turbine is in service, which is used to ensure the safe operation and working efficiency of large turbines. Because the turbine is in service for a long time under harsh environments such as high pressure, heavy load, vibration, and corrosion, the steel plates of the inner wall of the large turbine runner chamber are very likely to fail in different forms due to cavitation and abrasion. After the steel plates of the inner wall of the large turbine runner chamber fail, it is usually necessary to shut down for maintenance. During the entire life cycle of the inner wall of the turbine runner chamber, the total length of time the hydropower unit is shut down for maintenance will ultimately determine its economic losses. Therefore, it is of great significance to develop high-quality large turbine runner chamber wall repair and remanufacturing methods to improve the service performance and life of the inner wall of the runner chamber to be repaired.

[0003] In engineering, the failure defects of the inner wall of the runner chamber of large turbines are usually repaired by surfacing or additive manufacturing. Due to the violent metallurgical reactions and special thermal boundary conditions in the additive repair process, large-sized columnar crystals and high levels of residual tensile stress are usually present in the repair layer of the inner wall of the runner chamber. At the same time, the repair of the inner wall of the runner chamber of large turbines has the following engineering reality, that is, it cannot be disassembled for offline repair, and can only be repaired by on-site construction. However, the on-site construction method has the problem of not being able to perform good heat treatment, resulting in the general problem of insufficient mechanical properties of the additive repair layer of the inner wall of the turbine runner chamber, which seriously affects its final service performance and life. Therefore, solving the problems of coarse structure and high level of residual stress of the repair layer during on-site additive repair and remanufacturing is the key to achieving high-quality repair of the inner wall of the runner chamber of large turbines. Summary of the invention

[0004] The technical problem to be solved by the present invention is to address the deficiencies of the above-mentioned prior art and to provide a high-temperature synchronous micro-hammer forging assisted additive repair and remanufacturing system and process method for the inner wall of a turbine runner chamber. Based on the proposed repair and remanufacturing system, during the additive repair and remanufacturing process of the inner wall of a turbine runner chamber, a micro-forging hammer is used to perform synchronous high-temperature hammering on the additive deposited weld. In the absence of good post-weld heat treatment conditions, the principle of intermittent thermoplastic deformation by high-temperature hammering is used to solve the problem of coarse columnar crystals and high levels of residual tensile stress in the repair layer, thereby solving the problem of insufficient mechanical properties of the repair layer and improving the service performance of the inner wall of the runner chamber.

[0005] In order to realize the above-mentioned technical features, the purpose of the present invention is achieved as follows: On the one hand, the present invention provides a high-temperature synchronous micro-hammer forging assisted large-scale turbine runner chamber inner wall additive repair and remanufacturing system, the repair and remanufacturing system includes a penetration flaw detection module, a pre-processing milling grinding and root cleaning module, a pre-processing area induction preheating and temperature control module, a pre- / post-processing carrying and processing trajectory control robot, an additive deposition module, a synchronous micro-hammer forging module, an integrated clamping and temperature control module, an additive and micro-hammer forging carrying and trajectory control robot, a post-processing milling grinding and shaping module and a circular track carrying module; The pre-processing milling and grinding root cleaning module, the pre-processing area induction preheating and temperature control module and the post-processing milling and grinding shaping module are respectively connected to the pre-processing / post-processing carrying and processing trajectory control robot at different stages of the repair pre-processing / post-processing, and the pre-processing / post-processing carrying and processing trajectory control robot controls their movement and processing trajectory; The additive deposition module and the synchronous micro-hammer forging module are integrated into the additive and micro-hammer forging transport and trajectory control robot through an integrated clamping and temperature control module, and the additive and micro-hammer forging transport and trajectory control robot controls their motion trajectories and executes the additive and micro-hammer forging processing trajectories.

[0006] The relative distance between the end additive actuator of the additive deposition module and the end micro forging hammer of the synchronous micro hammer forging module is adjusted through the integrated clamping and temperature control module, thereby adjusting the deformation temperature of the repair weld on the inner wall of the runner chamber for synchronous micro hammer forging.

[0007] On the other hand, the present invention provides a high-temperature synchronous micro-hammer forging assisted large-scale turbine runner chamber inner wall additive repair and remanufacturing method, comprising the following steps: Step 1: Remove the attachments, oil stains and rust dirt on the inner wall of the runner chamber to be repaired, and then determine the location, type and size of the defects on the inner wall of the runner chamber to be repaired through manual identification and combined with the penetration testing module; Step 2: Use the pre-processing / post-processing transport and processing trajectory to control the robot to carry the pre-processing milling and grinding root cleaning module to pre-process the local defects to be repaired on the inner wall of the wheel chamber. According to the position, type and size of the defects to be repaired determined in step 1, determine the position, area and depth of the area to be milled or polished. For superficial defects, grinding and root cleaning are performed, and for large-area deep pit defects, milling processing is performed to form a cavity to be repaired; Step 3: Use the pre- / post-processing transport and processing trajectory to control the robot to transport the pre-processing area induction preheating and temperature control module to perform high-frequency induction preheating on the inner wall of the runner chamber formed in step 2 and the nearby area, and control the preheating temperature to 250-300°C; Step 4: Use the additive deposition module and the synchronous micro-hammer forging module carried by the additive and micro-hammer forging carrier and trajectory control robot to perform additive filling on the preheated runner chamber inner wall cavity to be repaired, and simultaneously perform synchronous high-temperature micro-hammer forging with each repair weld as a basic unit, gradually forming each layer of repair weld layer, and accumulating layer by layer until each cavity to be repaired on the inner wall of the runner chamber is completely filled with repair metal, wherein the additive filling adopts a horizontal welding method to avoid serious flow of the molten pool; in addition, it is required that the outer surface of the repair layer finally filled is 1mm~2mm higher than the substrate surface near the cavity to be repaired; Step 5: Use the pre- / post-processing transport and processing trajectory to control the robot to transport the post-processing milling and grinding shaping module to mill or grind the metal of the inner wall defect repair area of ​​the runner chamber that exceeds the inner wall substrate surface until the inner wall repair area completely restores the original surface features; Step 6: Use the penetrant flaw detection module to perform PT penetrant flaw detection on the repaired inner wall area of ​​the runner chamber. If no defects are found, the inner wall repair is completed. If defects are found, repeat the above steps 1 to 5 until all defects on the inner wall are completely eliminated.

[0008] Preferably, the pre-processing milling and grinding root cleaning module and the post-processing milling and grinding shaping module share a processing operation component, and the processing operation component includes two types: a milling tool component and a grinding tool component. The milling tool component includes a diamond milling cutter, a drive motor, a force control, a coolant supply device, and a flange integrated mounting frame I; the grinding tool component includes a grinding wheel, a drive motor, a force control, and a flange integrated mounting frame II.

[0009] Preferably, the pre-treatment area induction preheating and temperature control module includes a high-frequency induction heating component, a temperature measurement and control component and a flange integrated mounting frame III, the high-frequency induction heating component group includes a high-frequency induction power supply, an induction coil and a coolant supply device, and the temperature measurement and control component includes a thermal imager and a display terminal.

[0010] Preferably, the pre- / post-processing transport and processing trajectory control robot is a six-degree-of-freedom heavy-duty industrial robot arm I, and the additive and micro-hammer forging transport and trajectory control robot is a six-degree-of-freedom heavy-duty industrial robot arm II.

[0011] Preferably, the additive deposition module comprises an additive deposition energy source, a feeding mechanism, a terminal additive actuator and a protective atmosphere, the additive deposition energy source is an arc welder, a plasma arc welder or a laser, and the terminal additive actuator is a welding gun or a laser head; Preferably, the synchronous micro-hammer forging module is composed of a micro-hammer forging motion excitation device and a terminal micro-forging hammer; The integrated clamping and temperature control module includes a flange integrated mounting frame IV, a pneumatic vibration isolation fixed end and a slidable clamp connecting end. The end additive actuator of the additive deposition module and the synchronous micro-hammer forging module are integrated into an integrated structure through the flange integrated mounting frame IV of the integrated clamping and temperature control module, and the end additive actuator of the additive deposition module is movably connected to the flange integrated mounting frame IV through the slidable clamp connecting end, and the flange mounting end of the flange integrated mounting frame IV is fixedly connected to the additive and micro-hammer forging carrier and trajectory control robot through the pneumatic vibration isolation fixed end.

[0012] Preferably, the annular track transport module comprises two parts, a robot transport and mobile control trolley and an annular track; the robot transport and mobile control trolley comprises a robot transport pallet, a vertical wheeled rolling and limiting assembly, a lateral stabilizing support wheel, and a driving motor and a driving wheel; the annular track comprises an inner ring guide rail and an outer ring guide rail; the inner ring guide rail and the outer ring guide rail are respectively fixedly connected to the inner wall of the wheel chamber through a supporting frame and are installed on the same plane; the robot transport and mobile control trolley is movably connected to the annular track through the vertical wheeled rolling and limiting assembly and the lateral supporting wheels, and under the limiting constraint, can move freely and safely and stably along the annular track without derailing; the driving motor is fixedly connected to the driving wheel, and the driving wheel is movably connected to the outer ring guide rail.

[0013] Preferably, the material used for repairing the inner wall of the runner chamber is a corrosion-resistant, wear-resistant, high-strength plastic material; The corresponding welding material grades are 0Cr13Ni5Mo, ER410NiMo, ER308L, ER309L or Stellite welding materials, and the welding material form is wire or powder; The temperature for micro-hammer forging of the repair weld is achieved by adjusting the physical position of the sliding clamp connection end relative to the flange integrated mounting frame IV, and then adjusting the physical distance between the additive actuator at the end of the additive deposition module and the micro-forging hammer at the end of the synchronous micro-hammer forging module. The minimum temperature for micro-hammer forging of the repair weld needs to be higher than the recrystallization temperature of the corresponding metal material, and the maximum temperature is based on not generating a brittle phase and not causing severe coarsening of recrystallized grains due to overheating.

[0014] The present invention has the following beneficial effects: 1. The present invention establishes a system and characteristic process method for additive repair and remanufacturing of the inner wall of a turbine runner chamber by arranging modular operating tools and motion control components such as a penetration testing module, a pre-treatment milling and grinding root cleaning module, a pre-treatment area induction preheating and temperature control module, an additive deposition module, a synchronous micro-hammer forging module, an integrated clamping and temperature control module, a post-treatment milling and grinding shaping module, and a circular track transport module. The system and process method can improve the repair efficiency and quality of the inner wall of the runner chamber, extend its service life, and significantly reduce economic losses. At the same time, it is also convenient to realize the fully automated repair and remanufacturing of the inner wall of the turbine runner chamber.

[0015] 2. The present invention proposes to repair and remanufacture the inner wall of the turbine runner chamber by using an additive method, and introduces high-temperature micro-hammer forging to synchronously process the repair weld, thereby forming a high-temperature synchronous micro-hammer forging assisted large-scale turbine runner chamber inner wall repair and remanufacturing process method. This process method can regulate the microstructure state and residual stress state of the repair layer in an environment lacking good heat treatment, improve the mechanical properties of the repair layer, extend the service life of the turbine runner chamber inner wall steel plate, and significantly reduce the economic losses caused by the failure of the turbine runner chamber inner wall. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0017] Figure 1 This is a schematic diagram of the main process scheme for the arc additive repair and remanufacturing of the inner wall of the runner chamber of a large turbine assisted by temperature-synchronous micro-hammer forging according to the present invention.

[0018] Figure 2 The present invention provides a process flow chart corresponding to the process scheme for repairing and remanufacturing the inner wall of a large turbine runner chamber.

[0019] Figure 3 This is a process principle diagram of the main scheme of arc additive repair and remanufacturing of the inner wall of the runner chamber of a large turbine assisted by temperature synchronous micro-hammer forging according to the present invention.

[0020] Figure 4 It is a schematic structural diagram of the circular track transport module proposed in the present invention.

[0021] In the figure: pre-processing milling, grinding and root cleaning module 1, pre-processing area induction preheating and temperature control module 2, pre- / post-processing carrying and processing trajectory control robot 3, arc additive deposition module 4, welding gun 4-1, synchronous micro-hammer forging module 5, terminal micro-forging hammer 5-1, integrated clamping and temperature control module 6, additive and micro-hammer forging carrying and trajectory control robot 7, post-processing milling, grinding and shaping module 8, circular track carrying module 9, robot carrying and mobile control trolley 9-1, robot carrying pallet 9-1-1, driving wheel 9-1-5, vertical wheel rolling and limit assembly 9-1-2, lateral stabilizing support wheel 9-1-3, driving motor 9-1-4, circular track 9-2, inner ring guide rail 9-2-1, outer ring guide rail 9-2-2, large wheel chamber inner wall 10, cavity to be repaired 10-1, repair weld 10-2, repair weld layer 10-3. DETAILED DESCRIPTION

[0022] The high-temperature synchronous micro-hammer forging assisted large-scale turbine runner room wall additive repair and remanufacturing system and process method of the present invention are selected to repair and remanufacture the large-scale turbine runner room wall, and the additive deposition module is selected as an arc additive as a specific embodiment, that is, the high-temperature synchronous micro-hammer forging assisted turbine runner room wall arc additive remanufacturing is used as a specific embodiment. The described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] like Figure 1 , Figure 2 , Figure 3 , Figure 4 As shown, a high-temperature synchronous micro-hammer forging assisted large-scale turbine runner chamber inner wall arc additive repair and remanufacturing system, the repair and remanufacturing system includes the following modules: Penetrant flaw detection module: Use PT penetrant flaw detection technology to non-destructively detect 10 failure defects on the inner wall of the turbine runner chamber to determine the defect location, type and size; Pre-treatment milling and grinding root cleaning module 1: Use a milling or grinding tool assembly to perform milling or grinding pre-treatment on the defect on the inner wall and the surrounding area before repairing the failure defect of the inner wall of the runner chamber to expose the metallic luster and form a cavity 10-1 to be repaired.

[0024] Pre-treatment area induction preheating and temperature control module 2: uses high-frequency induction heating components to preheat the cavity 10-1 to be repaired and the surrounding area formed by milling or grinding the inner wall defects of the runner chamber, and monitors the regional temperature in real time; post-treatment milling and grinding shaping module 8, after the additive filling of the cavity 10-1 to be repaired with inner wall defects of the runner chamber is completed, is used to mill or grind the metal on the inner wall of the cavity 10-1 to be repaired that exceeds the surface of the inner wall matrix, so that the repair area can restore the original inner wall surface characteristics.

[0025] Pre- / post-processing transport and processing trajectory control robot 3: used to carry the above-mentioned pre-processing milling, grinding and root cleaning module 1, the pre-processing area induction preheating and temperature control module 2, and the post-processing milling, grinding and shaping module 8 at different stages of pre- / post-processing of the turbine runner chamber inner wall repair and remanufacturing, and control the above-mentioned modules to move along the predetermined trajectory to complete the corresponding processing operations.

[0026] Arc additive deposition module 4: responsible for filling the cavity 10-1 to be repaired formed after the pre-treatment of the inner wall 10 of the turbine runner chamber by using arc additive method.

[0027] Synchronous micro-hammer forging module 5: When the arc additive deposition module 4 is used to fill the cavity 10-1 to be repaired, the additive repair weld 10-2 is simultaneously subjected to high-temperature intermittent hammer deformation, and the intermittent thermoplastic deformation is used to improve the structure and stress state of the repair weld 10-2 and enhance the mechanical properties.

[0028] Integrated clamping and temperature control module 6: used to integrate the additive deposition module 4 and the synchronous micro-hammer forging module 5 into the same carrier equipment to avoid motion interference between the related components of the additive deposition module 4 and the synchronous micro-hammer forging module 5. In addition, it is also used to adjust the intervention temperature of the additive repair weld 10-2 for synchronous micro-hammer forging, that is, the welding gun 4-1 of the arc additive deposition module 4 and the end micro-forging hammer 5-1 of the synchronous micro-hammer forging module 5 are adjusted by the integrated clamping and temperature control module 6. The relative distance between the two is adjusted, and then the deformation temperature of the additive repair weld 10-2 for synchronous micro-hammer forging is adjusted.

[0029] Additive and micro-hammer forging transport and trajectory control robot 7: the main equipment that integrates and carries the arc additive deposition module 4 and the synchronous micro-hammer forging module 5, and is responsible for controlling the walking path and posture of the welding gun 4-1 and the end micro-forging hammer 5-1 on the inner wall of the rotary chamber, that is, the arc additive deposition module 4 and the synchronous micro-hammer forging module 5 are integrated into the additive and micro-hammer forging transport and trajectory control robot 7 through the integrated clamping and temperature control module 6, and the additive and micro-hammer forging transport and trajectory control robot 7 controls its motion trajectory and the processing trajectory of the arc additive and micro-hammer forging operations.

[0030] Furthermore, the pre-processing milling and grinding root cleaning module 1 and the post-processing milling and grinding shaping module 8 share a processing operation component, and the processing operation component includes two types of milling tool components and grinding tool components. The milling tool component mainly includes a diamond milling cutter, a drive motor, a force control, a coolant supply device, a flange integrated mounting frame Ⅰ, etc. The diamond milling cutter, the drive motor, the force control and the coolant supply device can be integrated into one through the flange integrated mounting frame Ⅰ to form a modular milling tool assembly. At the same time, the flange mounting end of the flange integrated mounting frame Ⅰ can be quickly connected to the pre- / post-processing transportation and processing trajectory control The robot 3 is connected to facilitate the component to perform milling processing on the defects to be repaired on the inner wall 10 of the turbine runner chamber according to the established trajectory; the grinding tool component mainly includes a grinding wheel, a drive motor, a force control, a flange integrated mounting frame II, etc., and the grinding wheel, the drive motor, the force control, etc. can be integrated into one through the flange integrated mounting frame II to form a modular grinding tool component. At the same time, the flange mounting end of the flange integrated mounting frame II can be quickly connected to the front / post-processing transportation and processing trajectory control robot 3, so that the component can perform grinding processing on the defects to be repaired on the inner wall 10 of the turbine runner chamber according to the established trajectory.

[0031] Furthermore, the pre-processing area induction preheating and temperature control module 2 includes a high-frequency induction heating component, a temperature measurement and control component and a flange integrated mounting frame III. The high-frequency induction heating component mainly includes a high-frequency induction power supply, an induction coil, a coolant supply device, etc., and the temperature measurement and control component mainly includes a thermal imager and a display terminal. The high-frequency induction power supply, the induction coil, the coolant supply device, the thermal imager, etc. can be integrated into one through the flange integrated mounting frame III to form a modular induction preheating and temperature control component. At the same time, the flange mounting end of the flange integrated mounting frame III can be quickly connected to the pre- / post-processing transport and processing trajectory control robot 3, so that the component can perform induction preheating and temperature control treatment on the formed turbine runner chamber inner wall 10 to be repaired cavity 10-1 and the surrounding area according to the established trajectory.

[0032] Furthermore, the pre- / post-processing transport and processing trajectory control robot 3 is a six-degree-of-freedom heavy-duty industrial robot arm I, and the additive and micro-hammer forging transport and trajectory control robot 7 is a six-degree-of-freedom heavy-duty industrial robot arm II.

[0033] Furthermore, the arc additive deposition module 4 mainly includes an arc welder, a wire feeding mechanism, a welding gun 4-1 and a protective atmosphere, etc. The synchronous micro-hammer forging module 5 mainly includes an electric micro-hammer forging motion excitation device and a terminal micro-forging hammer 5-1, wherein the terminal micro-forging hammer 5-1 is a flat hammer, and the cross-sectional diameter of the forging hammer is slightly larger than the weld width obtained under the optimized additive deposition process.

[0034] Furthermore, the integrated clamping and temperature control module 6 mainly includes a flange integrated mounting frame IV, a pneumatic vibration elimination fixed end, a slidable clamp connection end, etc. The welding gun 4-1 of the arc additive deposition module 4 and the synchronous micro-hammer forging module 5 can be integrated into an integrated structure through the integrated clamping and temperature control module 6 flange integrated mounting frame IV, and the welding gun 4-1 of the arc additive deposition module 4 is movably connected to the flange integrated mounting frame IV through the slidable clamp connection end, so that the welding gun 4-1 can slide on the flange integrated mounting frame IV with the slidable clamp connection end, adjust the distance between the welding gun 4-1 and the micro-forging hammer 5-1 at the end of the synchronous micro-hammer forging module 5, and then adjust the temperature of the additive repair weld 10-2 for micro-hammer forging. The flange mounting end of the flange integrated mounting frame IV is fixedly connected to the additive and micro-hammer forging carrying and trajectory control robot 7 through a pneumatic vibration-absorbing fixed end. In this way, when the additive and micro-hammer forging carrying and trajectory control robot 7 carries the arc additive deposition module 4 and the synchronous micro-hammer forging module 5 to repair the cavity 10-1 to be repaired on the inner wall of the runner chamber, the influence of the synchronous micro-hammer forging vibration on the arc additive deposition module 4 can be reduced to ensure the forming accuracy.

[0035] Furthermore, the annular track transport module 9 is used to carry and control the industrial robot and related repair and remanufacturing components required for repair and remanufacturing, so that they can move freely along the annular track of the annular wall to repair defects at any position on the inner wall of the wheel chamber. The annular track transport module 9 mainly includes two parts: a robot transport and mobile control trolley 9-1 and an annular track 9-2. The robot transport and mobile control trolley 9-1 is used to carry robots and repair and remanufacturing components, and mainly includes a robot transport pallet 9-1-1, which is the position of the industrial robot fixed on the trolley, a vertical wheeled rolling and limiting component 9-1-2 and a lateral stabilizing support wheel 9-1-3, which is a trolley rolling component and plays a limiting role. The trolley carrying robot and repaired and remanufactured components can move freely on the circular track without slipping off the track. The driving motor 9-1-4 and the driving wheel 9-1-5 are the driving and control devices of the trolley. The driving motor 9-1-4 is fixedly connected to the driving wheel 9-1-5, and the driving wheel 9-1-5 is movably connected to the outer ring guide rail 9-2-2. The driving wheel 9-1-5 drives the trolley to move through the friction between the outer ring guide rail 9-2-2. The circular track 9-2 includes an inner ring guide rail 9-2-1 and an outer ring guide rail 9-2-2. The inner ring guide rail 9-2-1 and the outer ring guide rail 9-2-2 are fixedly connected to the inner wall 10 of the wheel chamber through a support frame, and are installed on the same plane.

[0036] Furthermore, the material used for repairing the inner wall of the runner chamber of the large turbine is a welding wire with a grade of 0Cr13Ni5Mo, which is an ultra-low carbon martensitic stainless steel welding wire. The temperature for micro-hammer forging of the additive repair weld 10-2 is achieved by adjusting the physical position of the sliding clamp connection end relative to the flange integrated mounting frame IV, and then adjusting the physical distance between the arc additive deposition module 4 welding gun 4-1 and the micro-forging hammer 5-1 at the end of the synchronous micro-hammer forging module 5. The temperature for micro-hammer forging of the additive repair weld 10-2 is preferably slightly higher than the austenite recrystallization temperature of martensitic stainless steel (about 950°C). At this time, incomplete recrystallization of austenite occurs at a higher temperature, and after cooling to room temperature, a martensitic structure with a relatively high degree of refinement can be obtained.

[0037] Embodiment 2: This embodiment provides a high-temperature synchronous micro-hammer forging assisted arc additive repair and remanufacturing process for the inner wall of a large turbine runner chamber, which specifically includes the following steps: Step 1: Remove the dirt, such as attachments, oil stains, rust, etc. on the inner wall 10 of the runner chamber to be repaired, and determine the position, type and size of the defects to be repaired on the inner wall 10 of the runner chamber by naked eyes and in combination with the penetration flaw detection module; Step 2: Use the pre-processing / post-processing transport and processing trajectory to control the robot 3 to carry the pre-processing milling and grinding cleaning module 1 to pre-process the local defects to be repaired on the inner wall 10 of the wheel chamber, remove the metal in the failure area, and form the cavity 10-1 to be repaired. According to the position, type and size of the defect to be repaired determined in the previous step, determine the position, area and depth of the area to be milled or polished, wherein the superficial defects are ground and cleaned, and the large-area deep pit defects are milled; Step 3: Use the pre- / post-processing transport and processing trajectory to control the robot 3 to transport the pre-processing area induction preheating and temperature control module 2 to perform high-frequency induction preheating on the inner wall of the runner chamber to be repaired cavity 10-1 and the surrounding area formed in the previous step, and control the preheating temperature to 250-300°C to reduce the high level of residual tensile stress and deformation caused by the extremely cold and hot characteristics during the additive deposition in the local area; Step 4: Use the additive and micro-hammer forging carrier and trajectory control robot 7 to carry the arc additive deposition module 4 and the synchronous micro-hammer forging module 5 to perform additive filling on the preheated runner chamber inner wall to-be-repaired cavity 10-1, and at the same time use each additive repair weld bead 10-2 as a basic unit to perform synchronous high-temperature micro-hammer forging, gradually forming each layer of repair weld layer 10-3, and stacking them layer by layer until each runner chamber inner wall to-be-repaired cavity 10-1 is completely filled with repair metal, wherein the additive filling adopts a horizontal welding method to avoid serious flow of the molten pool. In addition, it is required that the outer surface of the repair layer finally filled is about 1 mm higher than the substrate surface near the cavity to be repaired 10-1, so that it is convenient for post-processing to shape the runner chamber inner wall repair area, so that the runner chamber inner wall repair area can quickly restore the original surface features. In addition, the additive deposition process parameters adopted by the arc additive deposition module 4 are the optimal process parameters obtained by experimental optimization, and the micro-hammer forging process parameters adopted by the synchronous micro-hammer forging module 5, including micro-hammer forging temperature, micro-hammer forging deformation and micro-forging hammer shape, are the optimal micro-hammer forging process parameters determined under the above-mentioned optimal additive deposition process parameters. The additive deposition process parameter optimization experiment and the process of determining the optimal micro-hammer forging process parameters are both carried out under the condition of a preheating temperature of 250-300°C; Step 5: Use the pre- / post-processing transport and processing trajectory to control the robot 3 to carry the post-processing milling and grinding shaping module 8 to mill or grind the metal of the inner wall defect repair area of ​​the runner chamber that exceeds the inner wall substrate surface until the inner wall repair area completely restores the original surface features; Step 6: Use the penetrant flaw detection module to perform PT penetrant flaw detection on the repaired inner wall area of ​​the runner chamber. If no defects are found, the inner wall repair is completed. If defects are found, repeat the above steps until all defects on the inner wall are completely eliminated.

Claims

1. A high-temperature synchronous micro-hammer forging assisted large-scale turbine runner chamber inner wall additive repair and remanufacturing system, characterized in that: The repair and remanufacturing system comprises a penetrant flaw detection module, a pre-processing milling, grinding and root cleaning module (1), a pre-processing area induction preheating and temperature control module (2), a pre- / post-processing transport and processing trajectory control robot (3), an additive deposition module (4), a synchronous micro-hammer forging module (5), an integrated clamping and temperature control module (6), an additive and micro-hammer forging transport and trajectory control robot (7), a post-processing milling, grinding and shaping module (8) and a circular track transport module (9); The pre-processing milling and grinding root cleaning module (1), the pre-processing area induction preheating and temperature control module (2), and the post-processing milling and grinding shaping module (8) are respectively connected to the pre-processing / post-processing transport and processing trajectory control robot (3) at different stages of the repair pre-processing / post-processing, and their movement and processing trajectory are controlled by the pre-processing / post-processing transport and processing trajectory control robot (3); The additive deposition module (4) and the synchronous micro-hammer forging module (5) are integrated into an additive and micro-hammer forging transport and trajectory control robot (7) via an integrated clamping and temperature control module (6), and the additive and micro-hammer forging transport and trajectory control robot (7) controls their motion trajectories and executes the additive and micro-hammer forging processing trajectories.

2. According to claim 1, a high-temperature synchronous micro-hammer forging assisted large-scale turbine runner chamber inner wall additive repair and remanufacturing system, characterized in that: The relative distance between the end additive actuator (4-1) of the additive deposition module (4) and the end micro-forging hammer (5-1) of the synchronous micro-hammer forging module (5) is adjusted through the integrated clamping and temperature control module (6), thereby adjusting the deformation temperature of the repair weld (10-2) on the inner wall (10) of the wheel chamber for synchronous micro-hammer forging.

3. A high-temperature synchronous micro-hammer forging assisted additive repair and remanufacturing method for the inner wall of a large turbine runner chamber, the method is implemented by the repair and remanufacturing system according to any one of claims 1-2, characterized in that: The following steps are involved: Step 1: remove the surface attachments, oil stains and rust stains on the inner wall (10) of the runner chamber to be repaired, and then determine the location, type and size of the defect to be repaired on the inner wall (10) of the runner chamber by manual identification combined with a penetrant flaw detection module; Step 2: Using the pre-processing / post-processing transport and processing trajectory control robot (3) to carry the pre-processing milling grinding and root cleaning module (1) to pre-process the local defect to be repaired generated on the inner wall (10) of the wheel chamber, and determine the position, area and depth of the area to be milled or polished according to the position, type and size of the defect to be repaired determined in step 1, wherein the grinding and root cleaning treatment is performed for superficial defects, and the milling processing is performed for large-area deep pit defects, so as to form a cavity to be repaired (10-1); Step 3: Using the pre-processing / post-processing transport and processing trajectory control robot (3) to transport the pre-processing area induction preheating and temperature control module (2) to perform high-frequency induction preheating on the inner wall of the runner chamber to be repaired cavity (10-1) and the surrounding area formed in step 2, and control the preheating temperature to be 250-300°C; Step 4: using an additive and micro-hammer forging transport and trajectory control robot (7) to carry an additive deposition module (4) and a synchronous micro-hammer forging module (5) to perform additive filling on the preheated runner chamber inner wall cavity to be repaired (10-1), and simultaneously performing synchronous high-temperature micro-hammer forging with each repair weld bead (10-2) as a basic unit, gradually forming each layer of repair weld layer (10-3), and stacking them layer by layer until each cavity to be repaired (10-1) on the inner wall of the runner chamber is completely filled with repair metal, wherein the additive filling adopts a horizontal welding method to avoid serious flow of the molten pool; in addition, it is required that the outer surface of the repair layer finally filled is 1 mm to 2 mm higher than the substrate mold surface near the cavity to be repaired (10-1); Step 5: Using the pre- / post-processing transport and processing trajectory control robot (3) to transport the post-processing milling and grinding shaping module (8), the metal of the defect repair area of ​​the inner wall of the runner chamber that exceeds the surface of the inner wall substrate is milled or polished until the inner wall repair area completely restores the original surface features; Step 6: Use the penetrant flaw detection module to perform PT penetrant flaw detection on the repaired inner wall area of ​​the runner chamber. If no defects are found, the inner wall repair is completed. If defects are found, repeat the above steps 1 to 5 until all defects on the inner wall are completely eliminated.

4. According to claim 2, a high-temperature synchronous micro-hammer forging assisted large-scale turbine runner chamber inner wall additive repair and remanufacturing method is characterized in that: The pre-processing milling grinding and root cleaning module (1) and the post-processing milling grinding and shaping module (8) share a processing operation component, and the processing operation component includes two types: a milling tool component and a grinding tool component. The milling tool component includes a diamond milling cutter, a drive motor, a force control, a coolant supply device, and a flange integrated mounting frame I, and the grinding tool component includes a grinding wheel, a drive motor, a force control, and a flange integrated mounting frame II.

5. According to claim 2, a high-temperature synchronous micro-hammer forging assisted large-scale turbine runner chamber inner wall additive repair and remanufacturing method is characterized in that: The pre-treatment area induction preheating and temperature control module (2) comprises a high-frequency induction heating component, a temperature measurement and control component and a flange integrated mounting frame III, the high-frequency induction heating component group comprises a high-frequency induction power supply, an induction coil and a coolant supply device, and the temperature measurement and control component comprises a thermal imager and a display terminal.

6. According to claim 2, a high-temperature synchronous micro-hammer forging assisted large-scale turbine runner chamber inner wall additive repair and remanufacturing method is characterized in that: The pre- / post-processing transport and processing trajectory control robot (3) is a six-degree-of-freedom heavy-duty industrial robot arm I, and the additive and micro-hammer forging transport and trajectory control robot (7) is a six-degree-of-freedom heavy-duty industrial robot arm II.

7. According to claim 2, a high-temperature synchronous micro-hammer forging assisted large-scale turbine runner chamber inner wall additive repair and remanufacturing method is characterized in that: The additive deposition module (4) comprises an additive deposition energy source, a feeding mechanism, a terminal additive actuator (4-1) and a protective atmosphere; the additive deposition energy source is an arc welder, a plasma arc welder or a laser; and the terminal additive actuator (4-1) is a welding gun or a laser head.

8. According to claim 2, a high-temperature synchronous micro-hammer forging assisted large-scale turbine runner chamber inner wall additive repair and remanufacturing method is characterized in that: The synchronous micro-hammer forging module (5) is composed of a micro-hammer forging motion excitation device and a terminal micro-forging hammer (5-1); The integrated clamping and temperature control module (6) comprises a flange integrated mounting frame IV, a pneumatic vibration-absorbing fixed end and a slidable clamp connection end. The end additive actuator (4-1) of the additive deposition module (4) and the synchronous micro-hammer forging module (5) are integrated into an integrated structure through the flange integrated mounting frame IV of the integrated clamping and temperature control module (6). The end additive actuator (4-1) of the additive deposition module (4) is movably connected to the flange integrated mounting frame IV through the slidable clamp connection end. The flange mounting end of the flange integrated mounting frame IV is fixedly connected to the additive and micro-hammer forging carrier and trajectory control robot (7) through the pneumatic vibration-absorbing fixed end.

9. According to claim 8, a high-temperature synchronous micro-hammer forging assisted large-scale turbine runner chamber inner wall additive repair and remanufacturing method is characterized in that: The annular track transport module (9) comprises two parts: a robot transport and mobile control trolley (9-1) and an annular track (9-2). The robot transport and mobile control trolley (9-1) comprises a robot transport pallet (9-1-1), a vertical wheeled rolling and limiting assembly (9-1-2), a lateral stabilizing support wheel (9-1-3), a driving motor (9-1-4) and a driving wheel (9-1-5). The annular track (9-2) comprises two parts: an inner ring guide rail (9-2-1) and an outer ring guide rail (9-2-2). The rails (9-2-2) are fixedly connected to the inner wall (10) of the wheel chamber through support frames and are installed on the same plane. The robot carrying and mobile control trolley (9-1) is movably connected to the circular rail (9-2) through a vertical wheel rolling and limit assembly (9-1-2) and a lateral support wheel (9-1-3), and can move freely and safely and stably along the circular rail (9-2) without derailment under limit constraints. The drive motor (9-1-4) is fixedly connected to the drive wheel (9-1-5), and the drive wheel (9-1-5) is movably connected to the outer ring guide rail (9-2-2).

10. The high temperature synchronous micro-hammer forging assisted large turbine runner chamber inner wall additive repair and remanufacturing method according to claim 9, characterized in that: The material used for repairing the inner wall of the runner chamber is a corrosion-resistant, wear-resistant, high-strength plastic material; The corresponding welding material grades are 0Cr13Ni5Mo, ER410NiMo, ER308L, ER309L or Stellite welding materials, and the welding material form is wire or powder; The temperature of the micro-hammer forging of the repair weld (10-2) is achieved by adjusting the physical position of the slidable clamp connection end relative to the flange integrated mounting frame IV, thereby adjusting the physical distance between the additive actuator (4-1) at the end of the additive deposition module (4) and the micro-forging hammer (5-1) at the end of the synchronous micro-hammer forging module (5). The minimum temperature of the micro-hammer forging of the repair weld (10-2) needs to be higher than the recrystallization temperature of the corresponding metal material, and the maximum temperature is based on not generating a brittle phase and not causing severe coarsening of recrystallized grains due to overheating.

Images