Control method of cold isostatic pressing device

Abstract

The invention relates to the technical field of material processing, and particularly relates to a control method of a cold isostatic pressing device, which realizes stable control of dynamic adjustment of pressurization, pressure maintaining and pressure relief stages through multi-parameter cooperative monitoring so as to improve the control efficiency of the cold isostatic pressing device. According to the invention, through detection from surface inspection to internal characteristics, no leakage and correct placement of materials can be ensured, pressurization safety supervision is carried out from a pressurization angle, so that the pressure in the high-pressure bin is stably increased according to a standard pressure increasing rate and a standard real-time pressure value, and the pressure in the high-pressure bin is increased along with a segmented pressure maintaining treatment process. According to the method, the control precision and strategy are adjusted in stages, the full-period requirement of materials from rapid densification to stress release is matched, the problem of excessive densification or insufficient densification caused by traditional constant-pressure pressure maintaining is solved, meanwhile, pressure relief is managed in real time, the backflow rate of hydraulic oil is controlled, and the working efficiency is improved. Material damage caused by too high speed of the high-pressure section is avoided, and the overall pressure reduction time is shortened.

Description

Technical Field

[0001] The present invention relates to the technical field of material processing, and in particular to a control method for a cold isostatic pressing device. Background Art

[0002] Cold isostatic pressing (CIP) uses a liquid medium to apply isotropic pressure to the material in a closed mold to achieve densification and molding. It is widely used in the fields of ceramics, metal powders, composite materials, etc. During the CIP process, the control accuracy of pressure and temperature directly affects the quality of the product, such as density uniformity and mechanical properties. Currently, traditional cold isostatic pressing control methods mostly use fixed pressurization rates, holding times, and pressure relief rates, which are difficult to dynamically adjust based on actual pressure and temperature changes. When pressure or temperature within the device fluctuates, defects such as cracks and uneven density can easily appear on the product, reducing the product's pass rate. In view of the above technical defects, a solution is now proposed. Summary of the Invention

[0003] The purpose of the present invention is to provide a control method for a cold isostatic pressing device to solve the above-mentioned technical defects. The present invention realizes stable control and safe processing of the cold isostatic pressing device through segmented supervision.

[0004] The object of the present invention can be achieved by the following technical solution: A control method for a cold isostatic pressing device comprises the following steps: Step 1: Place the material to be processed into a sealed elastic mold and place it in the high-pressure chamber of the cold isostatic pressing device. Perform self-inspection feedback analysis on the sealing status and material placement of the high-pressure chamber to obtain a pressure increase instruction or a fault instruction; Step 2: Pressurization phase: The boosting system is started, and the servo motor controls the hydraulic pump to deliver hydraulic oil to the booster. After being pressurized by the booster, the high-pressure liquid is sent to the high-pressure chamber. At the same time, the pressure supervision, evaluation and analysis are carried out to obtain a boost stabilization instruction or verification instruction. Step 3: Pressure holding stage: Based on the boost stabilization instruction and after the pressure in the high-pressure chamber reaches the set target pressure value, the pressure is kept stable so that the material is subjected to isostatic pressing under stable high pressure, accompanied by a pressure holding segmented management and analysis process; Step 4: Pressure relief stage: After the pressure maintenance is completed, the pressure relief operation begins; Step 5: Material removal stage: When the pressure in the high-pressure chamber drops to normal pressure, the high-pressure chamber is opened and the material that has been treated with cold isostatic pressing is taken out, completing a cold isostatic pressing process.

[0005] Preferably, the sealing status and material placement self-inspection feedback analysis process is as follows: S1: Sealing status detection process; S2: Material placement self-inspection process; S3: Information summary feedback analysis process: If the airtight signal, the normal signal and the uniform signal are generated simultaneously, a boost instruction is obtained; if the airtight signal, the normal signal and the uniform signal are not generated simultaneously, a fault instruction is obtained.

[0006] Preferably, S1 further includes S11: detecting the pre-tightening torque of the locking bolt by a torque sensor installed on the door locking mechanism, and monitoring the fitting gap between the door and the warehouse body by a displacement sensor, and performing discrimination processing on the pre-tightening torque and the fitting gap to obtain a sealing signal or an unsealing signal; S12: Based on the sealing signal, hydraulic medium is injected into the pressure chamber to obtain the pressure change in the monitoring chamber within a preset time period of t, where t is a natural number greater than zero, and whether the pressure change exceeds the preset pressure change threshold is judged and processed. If so, a sealing failure signal is generated; if not, an airtight signal is generated.

[0007] Preferably, S2 further includes S21: recording the weight of the empty bin bottom before the mold is placed, and automatically calculating the total weight G of the mold and the material after the mold is placed; S22: Obtain the standard deadweight of the mold and the preset filling weight range of the corresponding material, and determine whether the value obtained by subtracting the standard deadweight from the total weight G falls within the preset filling weight range. If so, a normal signal is generated; otherwise, an abnormal signal is generated; S23: After the mold is placed in place, the electromagnetic vibrator on the side wall of the chamber applies low-frequency sinusoidal vibration, and the piezoelectric acceleration sensor attached to the surface of the mold collects the vibration acceleration signal in real time to generate a vibration spectrum diagram. The vibration spectrum diagram is compared and analyzed with the preset vibration spectrum diagram to obtain the similarity between the vibration spectrum diagram and the preset vibration spectrum diagram. At the same time, the ultrasonic attenuation is obtained by symmetrically installing ultrasonic sensors on the top and bottom of the high-pressure chamber, and the similarity and ultrasonic attenuation are discriminated and processed to obtain a non-uniform signal or a uniform signal.

[0008] Preferably, the pressurization supervision assessment and analysis process is as follows: obtaining health information of the supercharger during the supercharging process, the health information including operating current, unit energy consumption, etc., inputting the health information into a preset health assessment model, obtaining the supercharging health score output by the health assessment model, and determining whether the supercharging health score exceeds a preset supercharging health score threshold. If so, a progressive signal is generated; if not, a risk instruction is generated.

[0009] Preferably, when a progressive signal is generated, the boost rate and real-time pressure value in the high-pressure chamber during the boosting process are obtained, and a boost rate characteristic curve and a real-time pressure value characteristic curve are constructed based on the time series. The overlapping parts of the boost rate characteristic curve and the real-time pressure value characteristic curve with the preset standard boost rate characteristic curve and the standard real-time pressure value characteristic curve are set as the boost fit and pressure fit, respectively, and the boost fit and pressure fit are judged and processed to obtain a boost stabilization instruction or a verification instruction.

[0010] Preferably, the pressure-maintaining segmented management and analysis process is as follows: reading the real-time pressure value Pfinal and temperature value Tfinal at the end of the pressurization stage; performing discrimination processing on the real-time pressure value Pfinal and temperature value Tfinal to obtain a feedback signal or a fine-tuning signal; When the feedback signal is generated, the holding stage is divided into the initial holding stage, the middle holding stage and the final holding stage.

[0011] Preferably, in the initial stage of pressure holding: the real-time pressure Preal, the maximum temperature difference ΔTmax, and the radial deformation rate of the mold in the high-pressure chamber during the pressure holding stage are obtained, and the real-time pressure Preal, the maximum temperature difference ΔTmax, and the radial deformation rate of the mold are collectively referred to as key parameters. The key parameters are then identified and processed. If an alarm signal is obtained, the comparison process corresponding to the alarm signal is set as an abnormality comparison, and the alarm signal + abnormality comparison is set as an alarm report. A pre-stored solution is obtained based on the alarm report. Mid-pressure holding phase: Obtain pressure compensation information and material stress information in the high-pressure chamber during the pressure holding phase. The pressure compensation information represents the pressure value at the last acquisition time minus the pressure value at the current acquisition time. The material stress information represents the value calculated by the difference between the radial stress and axial stress inside the material collected by the embedded stress sensor. The pressure compensation information and material stress information are discriminated and processed to obtain a preset pressure compensation rate step curve or pressure regulation instruction; At the end of pressure holding: active pressure replenishment is stopped. When the real-time pressure P is lower than the preset standard value, the preset minimum rate pressure replenishment is started. At the same time, the current average shrinkage rate of the material is collected and the average shrinkage rate is judged and processed to obtain the delay instruction or process instruction pressure relief rate curve.

[0012] Preferably, the pressure relief operation process is as follows: obtaining the pressure value of the hydraulic oil in the high-pressure chamber, and performing discrimination processing on the pressure value to obtain the high-pressure section, the medium-pressure section and the low-pressure section, and then obtaining the set pressure relief rates corresponding to the high-pressure section, the medium-pressure section and the low-pressure section; Based on the current pressure value in the chamber, the current set pressure relief rate and the actual pressure relief rate are obtained. If the actual pressure relief rate is less than the set pressure relief rate, an opening increase signal is generated. If the actual pressure relief rate is greater than or equal to the set pressure relief rate, an opening decrease signal is generated.

[0013] The beneficial effects of the present invention are as follows: (1) The present invention conducts safety supervision and analysis on the sealing and material placement of the cold isostatic pressing device, that is, from "surface inspection" to "internal characteristics detection", which helps to ensure that there is no leakage and the material is placed correctly. At the same time, through means such as vibration response and ultrasonic penetration, the internal filling state of the material is indirectly reflected, so that the operator can be prompted to take action based on information feedback; (2) The present invention performs pressurization safety supervision from the perspective of pressurization, thereby controlling the discharge volume and discharge pressure of the hydraulic oil discharged by the hydraulic pump, so that the pressure in the high-pressure chamber rises steadily according to the standard pressure increase rate and the standard real-time pressure value, and is accompanied by a segmented pressure maintenance process, that is, by adjusting the control accuracy and strategy in stages, matching the full cycle requirements of the material from rapid densification to stress release, solving the "over-densification" or "insufficient densification" problems caused by traditional constant pressure maintenance, and at the same time performing real-time management of pressure relief, thereby achieving control of the reflux rate of the hydraulic oil, avoiding material damage caused by excessively fast high-pressure section rates, and shortening the overall pressure reduction time. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The present invention will be further described below with reference to the accompanying drawings; Figure 1 It is a reference diagram of the method of the present invention; Figure 2 This is a local analysis diagram of Example 1 of the present invention; Figure 3 It is a reference schematic diagram of the material placement self-inspection process of the present invention. DETAILED DESCRIPTION

[0015] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0016] References to "embodiments" herein mean that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the present invention. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute a separate or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments; Example 1: Please refer to Figures 1 to 3 As shown, the present invention is a control method for a cold isostatic pressing device, comprising the following steps: Step 1: Place the material to be processed into a sealed elastic mold and place it in the high-pressure chamber of the cold isostatic pressing device. Perform self-inspection feedback analysis on the sealing status and material placement of the high-pressure chamber to obtain a pressure increase instruction or a fault instruction; Step 2: Pressurization phase: The boosting system is started, and the servo motor controls the hydraulic pump to deliver hydraulic oil to the booster. After being pressurized by the booster, the high-pressure liquid is sent to the high-pressure chamber. At the same time, the pressure supervision, evaluation and analysis are carried out to obtain a boost stabilization instruction or verification instruction. Step 3: Pressure holding stage: Based on the boost stabilization instruction and after the pressure in the high-pressure chamber reaches the set target pressure value, the pressure is kept stable so that the material is subjected to isostatic pressing under stable high pressure, accompanied by a pressure holding segmented management and analysis process; Step 4: Pressure relief stage: After the pressure maintenance is completed, the pressure relief operation begins; Step 5: Material removal stage: When the pressure in the high-pressure chamber drops to normal pressure, the high-pressure chamber is opened and the material that has been treated with cold isostatic pressing is taken out, completing one cold isostatic pressing process; The material to be processed is loaded into a sealed elastic mold and placed in the high-pressure chamber of the cold isostatic pressing device. Sensors detect the sealing status of the high-pressure chamber and the placement of the material. This self-inspection feedback analysis of the sealing status and material placement generates a pressure increase command or a fault command, thereby helping to ensure no leakage and correct material placement. If a fault command is detected, the system issues an alarm and stops subsequent operations, prompting the operator to take corrective action. The sealing status and material placement self-inspection feedback analysis process is as follows: S1: Sealing status detection process: S11: Detecting the pre-tightening torque of the locking bolt by a torque sensor installed on the door locking mechanism, and monitoring the fitting gap between the door and the warehouse body by a displacement sensor, and performing discrimination processing on the pre-tightening torque and the fitting gap. If the pre-tightening torque reaches a preset threshold and the fitting gap is less than a preset fitting gap threshold, a sealing signal is generated. If the pre-tightening torque does not reach the preset threshold, or the fitting gap is greater than or equal to the preset fitting gap threshold, an unsealed signal is generated. In response to the unsealed signal, corresponding operations are performed to prompt the operator to handle the problem. S12: Based on the sealing signal, a hydraulic medium is injected into the pressure chamber to obtain the pressure change in the monitoring chamber within a preset time period t, where t is a natural number greater than zero, and a determination is made as to whether the pressure change exceeds a preset pressure change threshold. If so, a sealing failure signal is generated; otherwise, an airtight signal is generated; This process avoids high-pressure leakage hazards through low-pressure pre-detection; S2: Material placement self-inspection process: S21: Record the weight of the empty bin bottom before placing the mold, and automatically calculate the total weight G of the mold and material after placing the mold; S22: Obtain the standard deadweight of the mold and the preset filling weight range of the corresponding material, and determine whether the value obtained by subtracting the standard deadweight from the total weight G falls within the preset filling weight range. If so, a normal signal is generated; otherwise, an abnormal signal is generated; S23: After the mold is placed in place, the electromagnetic vibrator on the side wall of the chamber applies low-frequency sinusoidal vibration, and the piezoelectric acceleration sensor attached to the surface of the mold collects the vibration acceleration signal in real time to generate a vibration spectrum diagram. The vibration spectrum diagram is compared and analyzed with a preset vibration spectrum diagram to obtain the similarity between the vibration spectrum diagram and the preset vibration spectrum diagram. At the same time, ultrasonic attenuation is obtained by symmetrically installing ultrasonic sensors on the top and bottom of the high-pressure chamber, and the similarity and ultrasonic attenuation are discriminated. If the similarity is less than a preset similarity threshold, or the ultrasonic attenuation is greater than a preset ultrasonic attenuation threshold, a non-uniform signal is generated. If the similarity is greater than or equal to the preset similarity threshold, and the ultrasonic attenuation is less than or equal to the preset ultrasonic attenuation threshold, a uniform signal is generated. S3: Information summary feedback analysis process: If the airtight signal, normal signal and uniform signal are generated at the same time, a boost instruction is obtained. If the airtight signal, normal signal and uniform signal are not generated at the same time, a fault instruction is obtained. The fault instruction is responded to and the corresponding operation is performed to prompt the operator to handle it; In the embodiments of the present invention, from "surface inspection" to "internal characteristics" detection: the existing technology mostly relies on manual observation to see whether the mold is full, or only weighs to determine the filling amount, which is unable to identify internal voids, uneven density and other problems; this method indirectly reflects the internal filling status of the material through means such as vibration response and ultrasonic penetration.

[0017] Example 2: Step 2: Pressurization phase: When a boost command is generated, the boost system is started, and the servo motor controls the hydraulic pump to deliver hydraulic oil to the booster. After being pressurized by the booster, the high-pressure liquid is delivered to the high-pressure chamber. At the same time, a pressure supervision evaluation and analysis is performed to obtain a pressure stabilization command or a verification command. The specific pressure supervision evaluation and analysis process is as follows: Obtain health information of the supercharger during the boosting process, including operating current and specific energy consumption. This information is then fed into a pre-set health assessment model to obtain a boost health score. A determination is then made as to whether the boost health score exceeds a preset boost health score threshold. If so, a progressive signal is generated; if not, a risk instruction is generated, and a pre-set warning action corresponding to the risk instruction is immediately taken. This allows for targeted management of the supercharger based on the information feedback to ensure boosting stability and reliability. When a progressive signal is generated, the boost rate and real-time pressure value in the high-pressure chamber during the boosting process are obtained, and a boost rate characteristic curve and a real-time pressure value characteristic curve are constructed based on the time series. The boost rate characteristic curve and the real-time pressure value characteristic curve are overlapped and analyzed with the preset standard boost rate characteristic curve and the standard real-time pressure value characteristic curve, and the overlapping parts of the boost rate characteristic curve and the real-time pressure value characteristic curve with the preset standard boost rate characteristic curve and the standard real-time pressure value characteristic curve are set as the boost fit and the pressure fit, respectively, and the boost fit and the pressure fit are calculated. The force fit is judged and processed. If the boost fit is greater than or equal to the boost fit threshold, and the pressure fit is greater than or equal to the preset pressure fit threshold, a boost stabilization instruction is generated. If the boost fit is less than the boost fit threshold, or the pressure fit is less than the preset pressure fit threshold, a verification instruction is generated. The verification instruction is responded to immediately, and the speed and torque of the servo motor are accurately adjusted through the servo motor controller to control the discharge volume and discharge pressure of the hydraulic oil discharged by the hydraulic pump, so that the pressure in the high-pressure chamber rises steadily according to the standard boost rate and standard real-time pressure value.

[0018] Example 3: Pressure holding stage: Based on the boost stabilization instruction and after the pressure in the high-pressure chamber reaches the set target pressure value, the pressure is kept stable so that the material is subjected to isostatic pressing under stable high pressure, accompanied by a pressure holding segmented management and analysis process: Read the real-time pressure value Pfinal and temperature value Tfinal at the end of the pressurization stage; The real-time pressure value P final and the temperature value T final are judged and processed. If the real-time pressure value P final falls within the preset real-time pressure value range, and the temperature value T final falls within the preset temperature value range, a feedback signal is generated. If the real-time pressure value P final does not fall within the preset real-time pressure value range, or the temperature value T final does not fall within the preset temperature value range, a fine-tuning signal is generated. In response to the fine-tuning signal, a pressure replenishment / pressure relief operation is performed on the pressure, or a temperature heating / cooling operation is performed on the temperature; When the feedback signal is generated, the pressure holding stage is divided into the initial pressure holding stage, the middle pressure holding stage and the final pressure holding stage; Initial stage of pressure holding: The real-time pressure Preal, the maximum temperature difference ΔTmax, and the mold radial deformation rate in the high-pressure chamber during the pressure holding stage are obtained. The real-time pressure Preal, the maximum temperature difference ΔTmax, and the mold radial deformation rate are collectively referred to as key parameters, and the key parameters are judged and processed. If at least one of the following occurs: the real-time pressure Preal is less than the minimum value in the preset real-time pressure range, the real-time pressure Preal is greater than the maximum value in the preset real-time pressure range, the maximum temperature difference ΔTmax is greater than the preset maximum temperature difference threshold, or the mold radial deformation rate is greater than the preset mold radial deformation rate threshold, an alarm signal is generated, the comparison process corresponding to the alarm signal is set as an abnormal comparison, and the alarm signal + abnormal comparison is set as an alarm report. Based on the alarm report, a pre-stored solution is obtained, and then the pre-stored solution is executed to adjust the parameters in the key parameters. For example: Alarm report: Alarm signal + real-time pressure P is less than the minimum value in the preset real-time pressure range, then the pre-stored solution is to open the micro-pressure relief valve; Alarm report: Alarm signal + maximum temperature difference ΔTmax is greater than the preset maximum temperature difference threshold, then the pre-stored solution is to open the temperature-averaging stirring device to make the temperature in the high-pressure chamber uniform, and so on; Mid-pressure holding period: Obtain the pressure compensation information and material stress information in the high-pressure chamber during the pressure holding period; The pressure compensation information represents the pressure value at the last acquisition time minus the pressure value at the current acquisition time; Material stress information refers to the value calculated by the difference between the radial stress and axial stress inside the material collected by the embedded stress sensor; The pressure compensation information and material stress information are discriminated and processed. If the pressure compensation information is greater than the preset pressure compensation information, a preset pressure compensation rate step curve is obtained, and pressure compensation control is performed according to the preset pressure compensation rate step curve. If the material stress information is greater than the preset material stress information, a pressure adjustment instruction is generated and executed to make the material stress information less than the preset set value, thereby reducing the risk of cracking in the later stage; At the end of pressure holding: stop active pressure replenishment. When the real-time pressure P is lower than the preset standard value, start the preset minimum pressure replenishment rate to ensure that the material will not rebound due to low pressure. At the same time, the current average shrinkage rate of the material is collected, and the average shrinkage rate is judged and processed. If the average shrinkage rate is less than the minimum value in the preset target shrinkage rate range, a delay instruction is generated, and the pressure holding delay processing is performed in response to the delay instruction. If the average shrinkage rate falls within the preset target shrinkage rate range, a process instruction is generated, and the response process instruction is carried out according to the normal process. If the average shrinkage rate is greater than the maximum value in the preset target shrinkage rate range, the difference between the average shrinkage rate and the maximum value in the preset target shrinkage rate range is obtained, and the difference is set as the pressure relief matching value. The pressure relief matching value obtained belongs to the corresponding preset pressure relief matching value interval and is set as the pressure relief rate curve. The pressure relief rate curve is used for pressure relief in the pressure relief stage; It should be noted that each preset pressure relief matching value interval is set with a corresponding pressure relief rate curve, and the pressure relief rate curve is different depending on the pressure relief matching value.

[0019] Example 4: In this embodiment of the present invention, the core of the pressure relief stage is to control the return rate of the hydraulic oil by adjusting the opening of the high-pressure chamber drain valve, so that the pressure in the high-pressure chamber drops steadily at a preset pressure relief rate; Pressure relief stage: After the pressure maintenance is completed, the pressure relief operation begins. The specific pressure relief operation process is as follows: The internal pressure value of the hydraulic oil in the high-pressure chamber is obtained, and the internal pressure value is judged. If the internal pressure value is greater than the maximum value in the preset internal pressure value range, it is determined to be a high-pressure section. If the internal pressure value is within the preset internal pressure value range, it is determined to be a medium-pressure section. If the internal pressure value is less than the minimum value in the preset internal pressure value range, it is determined to be a low-pressure section. The set pressure relief rates corresponding to the high-pressure section, medium-pressure section, and low-pressure section are then obtained. Based on the current pressure value in the bin, the current set pressure relief rate and the actual pressure relief rate are obtained. If the actual pressure relief rate is less than the set pressure relief rate, an opening increase signal is generated to increase the opening of the discharge valve. If the actual pressure relief rate is greater than or equal to the set pressure relief rate, an opening decrease signal is generated to reduce the opening of the discharge valve, thereby controlling the return rate of the hydraulic oil, avoiding material damage caused by excessively fast speed in the high-pressure section, and shortening the overall pressure reduction time. Material removal stage: When the pressure in the high-pressure chamber drops to normal pressure, the high-pressure chamber is opened and the material that has been treated with cold isostatic pressing is taken out, completing one cold isostatic pressing process; In summary, the present invention conducts safety supervision and analysis on the sealing and material placement of the cold isostatic pressing device, that is, from "surface inspection" to "intrinsic characteristics" detection, which helps to ensure that there is no leakage and the material is placed correctly. At the same time, through vibration response, ultrasonic penetration and other means, it indirectly reflects the internal filling state of the material, so that the operator can be prompted to take action based on information feedback, and performs pressurization safety supervision from the pressurization perspective, thereby controlling the discharge volume and discharge pressure of the hydraulic oil discharged by the hydraulic pump, so that the pressure in the high-pressure chamber rises steadily according to the standard pressure increase rate and standard real-time pressure value, and is accompanied by a segmented pressure maintenance treatment process, that is, by adjusting the control accuracy and strategy in stages, matching the full cycle requirements of the material from rapid densification to stress release, solving the "over-densification" or "insufficient densification" problems caused by traditional constant pressure maintenance, and performing real-time management of pressure relief, thereby realizing the control of the reflux rate of the hydraulic oil, which not only avoids material damage caused by excessively fast high-pressure section rate, but also shortens the overall pressure reduction time.

[0020] The threshold is set for result comparison and analysis to determine whether it is good or bad. The value of the threshold is set based on a combination of large-scale model analysis of sample data and manual experience to enter and store data. It can also be appropriately adjusted based on seasonal or common sense influencing conditions. The size of the coefficient is to quantify each parameter to obtain a specific numerical value, which is convenient for subsequent comparison. The size of the coefficient depends on the amount of sample data and the preliminary setting of the corresponding operating coefficient for each set of sample data by technical personnel in this field; as long as it does not affect the proportional relationship between the parameter and the quantized value.

[0021] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A control method for a cold isostatic pressing device, characterized in that: The following steps are involved: Step 1: Place the material to be processed into a sealed elastic mold and place it in the high-pressure chamber of the cold isostatic pressing device. Perform self-inspection feedback analysis on the sealing status and material placement of the high-pressure chamber to obtain a pressure increase instruction or a fault instruction; Step 2: Pressurization phase: The boosting system is started, and the servo motor controls the hydraulic pump to deliver hydraulic oil to the booster. After being pressurized by the booster, the high-pressure liquid is sent to the high-pressure chamber. At the same time, the pressure supervision, evaluation and analysis are carried out to obtain a boost stabilization instruction or verification instruction. Step 3: Pressure holding stage: Based on the boost stabilization instruction and after the pressure in the high-pressure chamber reaches the set target pressure value, the pressure is kept stable so that the material is subjected to isostatic pressing under stable high pressure, accompanied by a pressure holding segmented management and analysis process; Step 4: Pressure relief stage: After the pressure maintenance is completed, the pressure relief operation begins; Step 5: Material removal stage: When the pressure in the high-pressure chamber drops to normal pressure, the high-pressure chamber is opened and the material that has been treated with cold isostatic pressing is taken out, completing a cold isostatic pressing process.

2. The control method of a cold isostatic pressing device according to claim 1, characterized in that: The sealing status and material placement self-inspection feedback analysis process is as follows: S1: Sealing status detection process; S2: Material placement self-inspection process; S3: Information summary feedback analysis process: If the airtight signal, the normal signal and the uniform signal are generated simultaneously, a boost instruction is obtained; if the airtight signal, the normal signal and the uniform signal are not generated simultaneously, a fault instruction is obtained.

3. The control method of a cold isostatic pressing device according to claim 2, characterized in that: S1 also includes S11: detecting the pre-tightening torque of the locking bolt by a torque sensor installed on the door locking mechanism, and monitoring the fitting gap between the door and the warehouse body by a displacement sensor, and performing discrimination processing on the pre-tightening torque and the fitting gap to obtain a sealing signal or an unsealing signal; S12: Based on the sealing signal, hydraulic medium is injected into the pressure chamber to obtain the pressure change in the monitoring chamber within a preset time period of t, where t is a natural number greater than zero, and whether the pressure change exceeds the preset pressure change threshold is judged and processed. If so, a sealing failure signal is generated; if not, an airtight signal is generated.

4. The control method of a cold isostatic pressing device according to claim 2, characterized in that: S2 also includes S21: recording the weight of the empty bin bottom before the mold is placed, and automatically calculating the total weight G of the mold and the material after the mold is placed; S22: Obtain the standard deadweight of the mold and the preset filling weight range of the corresponding material, and determine whether the value obtained by subtracting the standard deadweight from the total weight G falls within the preset filling weight range. If so, a normal signal is generated; otherwise, an abnormal signal is generated; S23: After the mold is placed in place, the electromagnetic vibrator on the side wall of the chamber applies low-frequency sinusoidal vibration, and the piezoelectric acceleration sensor attached to the surface of the mold collects the vibration acceleration signal in real time to generate a vibration spectrum diagram. The vibration spectrum diagram is compared and analyzed with the preset vibration spectrum diagram to obtain the similarity between the vibration spectrum diagram and the preset vibration spectrum diagram. At the same time, the ultrasonic attenuation is obtained by symmetrically installing ultrasonic sensors on the top and bottom of the high-pressure chamber, and the similarity and ultrasonic attenuation are discriminated and processed to obtain a non-uniform signal or a uniform signal.

5. The control method of a cold isostatic pressing device according to claim 1, characterized in that: The pressurization supervision assessment and analysis process is as follows: obtaining health information of the supercharger during the supercharging process, the health information including operating current, unit energy consumption, etc., inputting the health information into a pre-set health assessment model, obtaining the supercharging health score output by the health assessment model, and determining whether the supercharging health score exceeds a preset supercharging health score threshold. If so, a progressive signal is generated; if not, a risk instruction is generated.

6. The control method of a cold isostatic pressing device according to claim 1, characterized in that: When a progressive signal is generated, the boost rate and real-time pressure value in the high-pressure chamber during the boosting process are obtained, and a boost rate characteristic curve and a real-time pressure value characteristic curve are constructed based on the time series. The overlapping parts of the boost rate characteristic curve and the real-time pressure value characteristic curve with the preset standard boost rate characteristic curve and the standard real-time pressure value characteristic curve are set as the boost fit and pressure fit, respectively, and the boost fit and pressure fit are judged and processed to obtain a boost stabilization instruction or a verification instruction.

7. The control method of a cold isostatic pressing device according to claim 1, characterized in that: The pressure-maintaining segmented management and analysis process is as follows: reading the real-time pressure value Pfinal and temperature value Tfinal at the end of the pressurization stage; performing discrimination processing on the real-time pressure value Pfinal and temperature value Tfinal to obtain a feedback signal or a fine-tuning signal; When the feedback signal is generated, the holding stage is divided into the initial holding stage, the middle holding stage and the final holding stage.

8. The control method of a cold isostatic pressing device according to claim 7, characterized in that: Initial stage of pressure holding: The real-time pressure Preal, maximum temperature difference ΔTmax, and radial deformation rate of the mold in the high-pressure chamber during the pressure holding phase are acquired. These are collectively referred to as key parameters and are identified and processed. If an alarm signal is generated, the comparison process corresponding to the alarm signal is set as an abnormality comparison. The alarm signal + abnormality comparison is set as an alarm report. Based on the alarm report, a pre-stored solution is obtained. Mid-pressure packing phase: Obtain pressure compensation information and material stress information in the high-pressure chamber during the pressure packing phase. The pressure compensation information represents the pressure value at the last acquisition time minus the pressure value at the current acquisition time. Material stress information refers to the value calculated by the difference between the radial stress and axial stress inside the material collected by the embedded stress sensor; The pressure compensation information and material stress information are discriminated and processed to obtain a preset pressure compensation rate step curve or pressure regulation instruction; At the end of pressure holding: active pressure replenishment is stopped. When the real-time pressure P is lower than the preset standard value, the preset minimum rate pressure replenishment is started. At the same time, the current average shrinkage rate of the material is collected and the average shrinkage rate is judged and processed to obtain the delay instruction or process instruction pressure relief rate curve.

9. The control method of a cold isostatic pressing device according to claim 1, characterized in that: The pressure relief operation process is as follows: the pressure value of the hydraulic oil in the high-pressure chamber is obtained, and the pressure value in the chamber is distinguished and processed to obtain the high-pressure section, the medium-pressure section and the low-pressure section, and then the set pressure relief rates corresponding to the high-pressure section, the medium-pressure section and the low-pressure section are obtained; Based on the current pressure value in the chamber, the current set pressure relief rate and the actual pressure relief rate are obtained. If the actual pressure relief rate is less than the set pressure relief rate, an opening increase signal is generated. If the actual pressure relief rate is greater than or equal to the set pressure relief rate, an opening decrease signal is generated.

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