An ultrahigh pressure vessel and internal heat conducting oil temperature control method

Abstract

The application relates to the field of isostatic pressing equipment, in particular to an ultrahigh-pressure container and an internal heat-conducting oil temperature control method and equipment. In the application, the medium oil tank in the ultrahigh-pressure container is respectively connected with an oil inlet pipeline and an oil return pipeline; the oil inlet pipeline is connected with a lower cover; heat-conducting oil in the medium oil tank is pumped into a cavity through the oil inlet pipeline; an electromagnetic induction coil is arranged on the outer side of a cylinder body; the electromagnetic induction coil is used for heating the heat-conducting oil in the cavity; an upper temperature sensor is arranged in the upper cover and is used for detecting the temperature of the heat-conducting oil close to the upper cover in the cavity; a lower temperature sensor is arranged in the lower cover and is used for detecting the temperature of the heat-conducting oil close to the lower cover in the cavity; the electromagnetic induction coil is arranged on the outer side of the cylinder body; an alternating magnetic field generated by the electromagnetic induction coil can uniformly penetrate the cylinder body, the heat-conducting oil in the cavity is heated as a whole, and the heating efficiency and the uniformity of the temperature are effectively improved.

Description

Technical Field

[0001] This invention relates to the field of isostatic pressure equipment, specifically to an ultra-high pressure vessel and a method for controlling the temperature of its internal heat transfer oil. Background Technology

[0002] A warm isostatic press is a device used to densify materials or products under high temperature and high pressure. It is primarily used to improve the performance of materials or products, such as eliminating porosity, increasing strength, and improving microstructure. The working principle of a warm isostatic press is based on the principle of isostatic pressing. At high temperature, a medium of oil at a specific temperature is injected into a high-pressure vessel, and high pressure is applied uniformly, thus applying the same pressure in all directions to the powder or product. This uniform pressure induces plastic deformation within the powder or product, reducing porosity and achieving densification.

[0003] Considering that the gaps between the liquid molecules of the heat transfer oil will change during the pressurization / depressurization process of the aforementioned high-pressure vessel, which manifests as an increase / decrease in Brownian motion at the microscopic level and as a change in temperature at the macroscopic level, this will affect the temperature uniformity of the medium inside the vessel, and thus affect the product quality.

[0004] Therefore, it is urgent to improve the high-pressure vessel and temperature isostatic pressing device in the existing temperature isostatic press in order to solve the technical defects in the existing technical solution. Summary of the Invention

[0005] One of the objectives of this application is to design an ultra-high pressure vessel to solve the problem of uneven temperature of the heat transfer oil in the cavity during the pressurization / depressurization process of existing high pressure vessels, in response to the existing technical solutions.

[0006] To achieve the above objectives, the present invention provides the following technical solution: An ultra-high pressure vessel includes a cylindrical body and an upper cover and a lower cover disposed on both sides of the cavity in the height direction of the cylindrical body. The cavity is used to assemble the powder or product to be pressurized. The upper cover and the lower cover are respectively connected to a medium oil tank. The medium oil tank is respectively connected to an oil inlet pipe and an oil return pipe. The oil inlet pipe is connected to the lower cover, and the heat transfer oil in the medium oil tank is pumped into the cavity through the oil inlet pipe; the heat transfer oil flows back from the cavity to the medium oil tank through the oil return pipe. An electromagnetic induction coil is installed on the outside of the cylinder, which is used to heat the heat transfer oil inside the cavity; An upper temperature sensor is installed in the upper cover to detect the temperature of the heat transfer oil near the upper cover inside the cavity; a lower temperature sensor is installed in the lower cover to detect the temperature of the heat transfer oil near the lower cover inside the cavity.

[0007] The above technical solution produces the following technical effects: This application utilizes an electromagnetic induction coil installed on the outside of the cylinder. The alternating magnetic field generated by the coil penetrates the cylinder uniformly, causing the heat transfer oil within the cavity to heat up uniformly, effectively improving heating efficiency and temperature uniformity. Specifically, during the pressurization or depressurization phase, when the upper and lower temperature sensors detect changes in the temperature of the heat transfer oil within the cavity, leading to changes in the intermolecular spacing of the heat transfer oil, the electromagnetic induction coil is driven to uniformly heat the heat transfer oil within the cavity. This alleviates the aforementioned changes in the intermolecular spacing of the heat transfer oil, improving the quality of the powder or product to be pressed.

[0008] As a further improvement to the ultra-high pressure vessel of this application, a hot oil tank is provided inside the medium oil tank. The hot oil tank is equipped with a heating component, which is used to heat the heat transfer oil in the hot oil tank or the heat transfer oil flowing into the hot oil tank from the return oil pipe to the preset process temperature. A circulation system is connected between the hot oil tank and the oil inlet pipe. The circulation system pumps the heat transfer oil into the cavity through an oil pump.

[0009] As a further improvement to the ultra-high pressure vessel of this application, a cold oil tank is provided inside the medium oil tank to store the cooled heat transfer oil. A pressurization system and a heater are connected between the cold oil tank and the oil inlet pipe. The pressurization system pumps the heat transfer oil into the cavity through an oil pump, and the heater heats the heat transfer oil pumped by the pressurization system.

[0010] As a further improvement to the ultra-high pressure vessel of this application, a pressure relief pipe is connected between the cold oil tank and the oil inlet pipe, and a first pressure relief valve is provided in the pressure relief pipe.

[0011] As a further improvement to the ultra-high pressure vessel of this application, a heating rod is provided inside the lower cover, which is used to heat the heat transfer oil in the oil inlet pipe.

[0012] As a further improvement to the ultra-high pressure vessel of this application, a steel strip winding layer and a heat insulation layer are provided in the electromagnetic induction coil and the cylinder. The steel strip winding layer is located on the outside of the cylinder, and the heat insulation layer is located on the outside of the steel strip winding layer.

[0013] As a further improvement to the ultra-high pressure vessel of this application, a protective layer is provided on the outside of the electromagnetic induction coil.

[0014] As a further improvement to the ultra-high pressure vessel of this application, a second pressure relief valve is provided in the oil return pipeline.

[0015] The second objective of this application is to design a method for controlling the temperature of heat transfer oil inside an ultra-high pressure vessel, in order to solve the problem of uneven temperature of the heat transfer oil inside the cavity during the pressurization, depressurization and pressure holding processes of existing high pressure vessels.

[0016] To achieve the above-mentioned objectives, this application implements the following technical solution: A method for controlling the temperature of heat transfer oil inside an ultra-high pressure vessel, as described above, includes the following steps: Step S1: Put the powder or product to be pressed into the cavity of the cylinder and set the set value T; Step S2: Preheat the heat transfer oil in the medium oil tank, pump the heat transfer oil into the cavity through the oil inlet pipe, and turn on the electromagnetic induction coil to heat the heat transfer oil in the cavity; Step S3: When the temperature of the heat transfer oil in the cavity reaches T3 as detected by the upper temperature sensor and / or lower temperature sensor, the return oil pipe is closed, and the heat transfer oil is pumped into the cavity through the inlet oil pipe to achieve pressurization. Step S4: Keep the electromagnetic induction coil working so that the temperature of the heat transfer oil in the cavity reaches the set value T. At the same time, adjust the power of the electromagnetic induction coil and close the oil inlet pipe so that the heat transfer oil in the cavity enters the pressure holding stage. Step S5: After the pressure holding stage, turn off the electromagnetic induction coil to allow the heat transfer oil in the cavity to enter the pressure relief stage. After the pressure relief stage, remove the powder or product from the cavity.

[0017] Through the above technical solution, this application achieves the following technical effects: In addition to utilizing electromagnetic induction coils to uniformly control the temperature of the heat transfer oil within the container during the pressurization and depressurization stages, this application also considers that during the pressure holding stage of existing high-pressure containers, convection is difficult to form in the heat transfer oil. The lower heat flux density rises, while the relatively higher cold flux sinks. Therefore, the temperature of the heat transfer oil within the high-pressure sealed container remains unevenly distributed, affecting product quality. Thus, in the method described in this application, while keeping the electromagnetic induction coil active during the pressure holding stage, its power is adjusted to continuously maintain the temperature of the heat transfer oil within the cavity at a set value T.

[0018] As a further improvement to the method for controlling the temperature of heat transfer oil inside an ultra-high pressure vessel according to this application, in step S3, when the difference between the upper temperature T1 detected by the upper temperature sensor and the lower temperature T2 detected by the lower temperature sensor satisfies: T1-T2≤2℃, the heating rod in the lower cover is driven to heat the heat transfer oil in the oil inlet pipe. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the ultra-high pressure vessel of the present invention; Figure 2 This is a flowchart illustrating the process of the heat transfer oil temperature control method inside the ultra-high pressure vessel of the present invention. Tag name: 1-Cylinder body; 11-Cavity; 12 - Electromagnetic induction coil; 13-Steel strip winding layer; 14 - Insulation layer; 15 - Protective layer; 2-Top cover; 21-Upper temperature sensor; 3- Bottom cover; 31-Lower temperature sensor; 32-Heating rod; 4-Medium oil tank; 41-Hot oil tank; 411 - Circulation system; 42 - Cold oil tank; 421 - Boost system; 4212 - Heater; 422 - Pressure relief pipe; 4221 - First pressure relief valve; 43 - Return oil pipeline; 431 - Second pressure relief valve; 5- Oil inlet pipe; T - Setting value; T1 - Upper layer temperature; T2 - Lower layer temperature. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] Specifically, this application understands that in the existing isostatic pressing process, heat transfer oil participates in the three steps of pressurization, pressure holding, and pressure release as a heat transfer and force transfer medium. First, the heat transfer oil is heated to the required temperature by a heating device, and then transported by an oil pump to a high-temperature and high-pressure sealed container through a pipeline. After the sealed high-pressure container is filled with atmospheric pressure, the same type of heat transfer oil at the same temperature is continuously injected into the high-pressure sealed container by a reciprocating circulation booster cylinder. The heat transfer oil in the high-pressure sealed container is in the pressurization stage.

[0022] Furthermore, when the pressure of the heat transfer oil in the high-pressure sealed container reaches the process requirement pressure, the booster cylinder stops pumping oil. At this time, the heat transfer oil is in the high-pressure holding stage. The pressure holding time is set according to the process requirements to continuously press the material. After the material is formed, the pressure of the heat transfer oil in the high-pressure sealed container is depressurized, and the material is taken out to complete the processing.

[0023] However, the above-mentioned technical solutions currently have the following shortcomings in the warm isostatic pressing equipment: 1. During the pressurization / depressurization process, the changes in the gaps between liquid molecules of the heat transfer oil result in the intensification / weakening of Brownian motion at the microscopic level, which manifests as temperature changes at the macroscopic level. This affects the temperature uniformity of the medium inside the container, and consequently, the product quality.

[0024] 2. During the pressure holding process, convection is difficult to form within the container. The heat flux, being less dense, rises, while the cold flux, being denser, sinks. Therefore, the temperature of the heat transfer oil within the high-pressure sealed container will be unevenly distributed, affecting product quality.

[0025] 3. During product processing, heat exchange between the medium and the environment will cause the temperature of the heat transfer oil to drop. Currently, most equipment uses the method of setting up an insulation layer 14 to reduce the temperature drop, but the effect is not ideal and the temperature accuracy is poor (±5℃). There are no other temperature control facilities.

[0026] 4. The heating / cooling process of the medium relies on the circulating heating / cooling of the mold temperature controller, which is inefficient and slow, affecting production capacity.

[0027] Therefore, this application generates the inventive motivation to improve the existing technical solution.

[0028] The following detailed description is exemplary and intended to provide further detailed explanation of the invention. Unless otherwise specified, all technical terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used in this invention is for describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention.

[0029] Example 1

[0030] like Figure 1 As shown, to address the problem of uneven temperature of the heat transfer oil medium inside the cavity 11 during the pressurization and depressurization stages in existing high-pressure vessels, this application specifically designs an ultra-high-pressure vessel to solve the aforementioned technical defects. The ultra-high-pressure vessel of this application includes a cylindrical body 1 and an upper cover 2 and a lower cover 3 disposed on both sides of the cavity 11 in the height direction within the cylindrical body 1. The cavity 11 is used to assemble the powder or product to be pressurized. The upper cover 2 and the lower cover 3 are respectively connected to a medium oil tank 4, and the medium oil tank 4 is respectively connected to an oil inlet pipe 5 and an oil return pipe 43. The main body of the cavity 11 is a cylindrical body 1 structure, and the upper cover 2 and the lower cover 3 serve as end cover assemblies, connected to the cylindrical body 1 via flanges to form a sealed cavity.

[0031] Furthermore, the oil inlet pipe 5 is connected to the lower cover 3, and the heat transfer oil in the medium oil tank 4 is pumped into the cavity 11 through the oil inlet pipe 5; the heat transfer oil flows back from the cavity 11 to the medium oil tank 4 through the return oil pipe 43; an electromagnetic induction coil 12 is provided on the outside of the cylinder 1, which is used to heat the heat transfer oil in the cavity 11. An upper temperature sensor 21 is provided in the upper cover 2, which is used to detect the temperature of the heat transfer oil near the upper cover 2 in the cavity 11; a lower temperature sensor 31 is provided in the lower cover 3, which is used to detect the temperature of the heat transfer oil near the lower cover 3 in the cavity 11. In the specific implementation process, the operator puts the powder or product to be pressed into the cavity 11 of the ultra-high pressure container, and the heat transfer oil medium, which has been heated by the circulation system 411 inside the medium oil tank 4, is pumped into the container cavity 11 through the oil inlet pipe 5 by the pressurization system 421. If the upper temperature sensor 21 and the lower temperature sensor 31 detect that the temperature of the medium inside the cavity 11 is lower than the set value T, the temperature can be raised by circulating through the inlet and outlet oil pipelines. At the same time, the electromagnetic induction coil 12 wound around the outside of the cylinder 1 will heat the medium inside the cavity 11, causing the temperature to rise rapidly.

[0032] In the aforementioned process, the existing technical solution only involves heating the circulating heat transfer oil through the circulation system 411. This process inevitably leads to the uneven heating of the heat transfer oil mentioned in this application. During the pressurization stage, the increased pressure reduces the molecular gaps and intensifies Brownian motion, macroscopically manifesting as a temperature rise; during the depressurization stage, the decreased pressure increases the molecular gaps and weakens Brownian motion, macroscopically manifesting as a temperature drop. Both processes cause fluctuations in the temperature of the medium within the container, disrupting the original temperature uniformity. In specific implementation, uneven temperature leads to local density and viscosity changes in the heat transfer oil, forming stratification of cold and hot flows (higher cold flow density sinks, lower hot flow density rises), similar to the pressure holding stage, disrupting the uniform force transmission of the medium to the product. Simultaneously, during the depressurization process, if different parts of the product experience inconsistent shrinkage rates due to temperature differences, internal stress is easily generated, potentially causing defects such as cracking and deformation. This invention solves the aforementioned technical defects by using an electromagnetic induction coil 12 to heat the heat transfer oil within the cavity 11 sufficiently and uniformly.

[0033] In this design, the upper temperature sensor 21 and the lower temperature sensor 31 detect temperatures separately. It is worth noting that due to the spatial size of the cavity 11, there is a high possibility of a temperature difference between the upper layer of the heat transfer oil near the upper cover 2 and the lower layer near the lower cover 3. Specifically, when the upper temperature sensor 21 and the lower temperature sensor 31 detect that the temperatures of the upper and lower layers of heat transfer oil exceed a certain value, the heating rod 32 installed in the lower cover 3 is controlled to heat the oil to make the lower layer temperature T2 consistent with the upper layer temperature T1. (Specifically, since the lower layer medium temperature is usually lower than the upper layer (due to the sinking characteristic of high cold flow density), the heating rod 32 in the lower cover 3 is activated first.) In the specific implementation process, due to this technical solution, the upper temperature sensor 21 and the lower temperature sensor 31 can be made to have a small error between them, and then the actual temperature of the heat transfer oil is calculated, and this calculated temperature is compared with the set value T. If the calculated actual temperature is lower than the set value T, the system will automatically adjust the power of the electromagnetic induction coil 12 to enhance the heating of the heat transfer oil, gradually raising the temperature of the heat transfer oil to the set value T range. If the actual temperature is higher than the set value T, the power of the electromagnetic induction coil 12 will decrease accordingly, slowing down the heating rate and allowing the temperature of the heat transfer oil to fall back to a suitable range. Preferably, the above temperature value can be calculated by taking the average value of the values ​​detected by the upper temperature sensor 21 and the lower temperature sensor 31. This calculation can more accurately reflect the overall temperature of the heat transfer oil in the cavity 11, avoiding large deviations in the judgment of the actual temperature due to the difference between the upper and lower temperatures T2. At the same time, in order to further improve the accuracy of temperature control, the average value calculation result can be appropriately corrected according to the specific dimensions of the cavity 11, the characteristics of the heat transfer oil, and the temperature fluctuations during actual use. For example, when the cavity 11 is high and the heat transfer oil has poor fluidity, the weight of the lower temperature T2 detection value in the calculation can be appropriately increased.

[0034] Furthermore, such as Figure 1 As shown, a hot oil tank 41 is installed inside the medium oil tank 4. The hot oil tank 41 is equipped with a heating component, which heats the heat transfer oil in the hot oil tank 41 or the heat transfer oil flowing into the hot oil tank 41 from the return oil pipe 43 to the preset process temperature. A circulation system 411 is connected between the hot oil tank 41 and the oil inlet pipe 5. The circulation system 411 pumps the heat transfer oil into the cavity 11 via an oil pump. In specific implementation, the heat transfer oil in the hot oil tank 41 is preheated by the heating component. Once the temperature reaches the preset range, the oil pump is started to send the heat transfer oil into the cavity 11. This prevents heat transfer oil that has not reached the required temperature from entering the cavity 11 and disrupting the internal temperature balance, reducing the adjustment range of subsequent temperature control, and improving the overall temperature control stability. During circulation, the medium oil tank 4 can store the heat transfer oil overflowing from the hot oil tank 41 and simultaneously help balance the pressure of the entire oil circuit system, ensuring smooth and stable oil circulation.

[0035] For details, please refer to [link / reference]. Figure 1 As shown, a cold oil tank 42 is installed inside the medium oil tank 4. The cold oil tank 42 is used to store the cooled heat transfer oil. A pressurization system 421 and a heater 4212 are connected between the cold oil tank 42 and the oil inlet pipe 5. The pressurization system 421 pumps the heat transfer oil into the cavity 11 via an oil pump, and the heater 4212 heats the heat transfer oil pumped by the pressurization system 421. In specific implementation, The cold oil tank 42 receives cooled heat transfer oil from external sources or circulated from the aforementioned hot oil tank 41. The cold oil tank 42 mainly operates during the pressurization stage. During pressurization, the heat transfer oil in the cold oil tank 42 is pumped into the cavity 11 via the pressurization system 421, which can quickly adjust the pressure inside the cavity 11 to meet process requirements. At the same time, the heater 4212 can compensate for the temperature of the heat transfer oil entering the cavity 11 based on the real-time temperature, avoiding large fluctuations in the internal temperature of the cavity 11 after the addition of cold oil. This balances the rhythm of temperature and pressure changes during the pressurization process, ensuring that the pressure increase meets the requirements of the ultra-high pressure process and that the temperature of the cavity 11 is stably controlled within a preset range, further improving the accuracy and stability of temperature control under ultra-high pressure conditions.

[0036] Furthermore, a pressure relief pipe 422 is connected between the cold oil tank 42 and the oil inlet pipe 5. The pressure relief pipe 422 is equipped with a first pressure relief valve 4221. When the ultra-high pressure process is completed and pressure reduction is required, the first pressure relief valve 4221 is opened, and the heat transfer oil that has completed heat exchange in the cavity 11 can be directly discharged into the cold oil tank 42 through the pressure relief pipe 422 to achieve rapid pressure reduction without having to go through the hot oil tank 41 for transfer. This shortens the time consumed in the pressure reduction process. In addition, the heat transfer oil discharged during the pressure reduction process directly enters the cold oil tank 42 for storage, which also avoids the high-temperature heat transfer oil occupying additional circulation space. This optimizes the space utilization rate of the entire heat transfer oil circulation system 411. At the same time, in conjunction with the existing pressure boosting and temperature compensation logic, the pressure and temperature preparation for the next process can be completed quickly, improving the overall efficiency of ultra-high pressure processing.

[0037] Furthermore, a second pressure relief valve 431 is installed inside the return oil pipe 43. After the pressure holding stage, the second pressure relief valve 431 opens, allowing the high-pressure heat transfer oil in the cavity 11 to flow back to the oil storage tank through the return oil pipe 43, thereby achieving pressure relief and cooling. The opening speed of the second pressure relief valve 431 can be precisely adjusted according to actual needs. If the pressure inside the cavity 11 is too high, the second pressure relief valve 431 can be opened slowly to prevent damage to the equipment from a sudden pressure drop; if the pressure is relatively low, the opening speed can be appropriately increased to improve the return oil efficiency. In addition, the heating rod 32 allows for rapid heating of the heat transfer oil during the pressurization stage, quickly raising the temperature of the heat transfer oil to meet the temperature requirements of the pressurization stage. The heating rod 32 can directly contact the heat transfer oil, efficiently converting electrical energy into heat energy, accelerating the heating rate of the heat transfer oil, and shortening the entire pressurization process time. Moreover, the power of the heating rod 32 can be flexibly adjusted according to actual needs.

[0038] Furthermore, this application understands that the existing technical solutions still suffer from uneven temperature of the heat transfer oil medium during the pressure holding stage. Therefore, when the high-pressure vessel is under pressure (the medium in the cavity 11 is in a closed state with no flow), if the temperature of the heat transfer oil medium drops, the heat is transferred to the heat transfer oil medium in the cavity 11 by heating with an electromagnetic heating coil to maintain the set temperature. The accuracy of the medium temperature is greatly improved, further ensuring the quality of the product.

[0039] Furthermore, it's important to understand that the electromagnetic induction coil 12 works by utilizing the principle of electromagnetic induction. Alternating current generates an alternating magnetic field within the coil. This magnetic field interacts with the metal material, inducing eddy currents within the metal. These eddy currents then generate heat through friction within the metal, thus heating the material. Figure 1 As shown, the high-pressure vessel cylinder 1 is heated by the electromagnetic induction coil 12, and the heat of the cylinder 1 is transferred to the medium, causing the medium to heat up rapidly. Electromagnetic induction heating has the following characteristics: 1. High efficiency and energy saving: Because it heats directly by generating eddies inside the object being heated, the heat is generated inside the object, reducing heat loss during the heat transfer process.

[0040] 2. Fast heating speed: Heat is generated inside the object, unlike traditional heating methods that require waiting for heat to gradually transfer from the outside to the inside.

[0041] 3. High control precision: Electromagnetic induction heating equipment can achieve precise control by adjusting multiple parameters such as the output power, frequency, and heating time of the high-frequency power supply, and can flexibly adjust the heating process according to different heating needs.

[0042] In summary, the temperature uniformity of the heat transfer oil medium inside the container of this application has been improved from ±5℃ to ±2℃, which significantly improves the quality of the product; the heating time of the medium inside the container has been shortened, increasing production capacity; and it has the advantages of high efficiency, energy saving, and environmental protection.

[0043] Furthermore, a steel strip winding layer 13 and a thermal insulation layer 14 are provided within the electromagnetic induction coil 12 and the cylinder 1. The steel strip winding layer 13 is located on the outside of the cylinder 1, and the thermal insulation layer 14 is located on the outside of the steel strip winding layer 13. The steel strip winding layer 13, wound using prestressed steel wire winding technology, provides circumferential prestress to the cylinder 1, counteracting the tensile stress generated by internal pressure, enabling the container to withstand ultra-high pressure conditions of ≥600MPa, thus solving the problem of weak load-bearing capacity and fatigue resistance in traditional non-steel wire wound high-pressure containers (point contact). The thermal insulation layer 14 blocks heat exchange between the internal medium and the external environment, reducing the temperature drop of the heat transfer oil and solving the problem of poor temperature control (temperature accuracy ±5℃) when relying solely on the thermal insulation layer 14. The protective layer 15 located on the outside of the electromagnetic induction coil 12 further addresses this technical issue.

[0044] Example 2

[0045] Unlike Example 1, in order to further address the issue of uneven heating of the heat transfer oil medium at different stages in the implementation of existing high-pressure vessels, this application designs a method for controlling the internal temperature of the heat transfer oil in any of the above-mentioned ultra-high-pressure vessels, such as... Figure 2 As shown, it includes the following steps: Step S1: The powder or product to be pressed is put into the cavity 11 of the cylinder 1, and a set value T is set. Specifically, the temperature sensor, electromagnetic coil, and heating rod 32 in the high-pressure container of this application are all managed by the control system (specifically, the PLC system). At the beginning stage of the device of this application, a set value T is set in the system to provide a control threshold for the next step.

[0046] Step S2: Preheat the heat transfer oil in the medium oil tank 4. Specifically, the heat transfer oil in the hot oil tank 41 is heated to the preset process temperature by a heating component. Then, the circulation system 411, which is connected to the outlet of the hot oil tank 41, pumps the heat transfer oil into the cavity 11 via an oil pump. Then, the electromagnetic induction coil 12 is activated to heat the heat transfer oil in the cavity 11. After the cavity 11 is filled with heat transfer oil, the heated oil in the cavity 11 is further forced out of the cavity 11 by newly pumped-in heat transfer oil and enters the return oil pipe 43, which connects to the upper cover 2. Subsequently, the heat transfer oil in the return oil pipe 43 flows back to the hot oil tank 41, thus forming a cyclic heating process. In this cycle, the circulation system 411 operates continuously, ensuring that the heat transfer oil can continuously flow in the medium oil tank 4 and the cavity 11. The oil pump operates stably, ensuring that the heat transfer oil has sufficient pressure to smoothly enter the cavity 11 through the oil inlet pipe 5. Meanwhile, the electromagnetic induction coil 12 continuously heats the heat-conducting oil in the cavity 11, so that the circulating heat-conducting oil can maintain a high temperature.

[0047] Step S3: When the temperature of the heat transfer oil in the cavity 11 reaches T3 temperature as detected by the upper temperature sensor 21 and / or the lower temperature sensor 31, the return oil pipe 43 and the circulation system 411 are closed, and the cooled heat transfer oil in the cold oil tank 42 is pumped into the cavity 11 through the oil inlet pipe 5 to achieve pressurization; specifically, the cooled heat transfer oil in the cold oil tank 42 is pressurized and injected into the cavity 11 by the oil pump. At this time, the pressure of the heat transfer oil in the cavity 11 reaches the preset ultra-high pressure, and the temperature in the cavity 11 will gradually decrease as the cold heat transfer oil is injected. By fine-tuning the output power of the electromagnetic induction coil 12, and with the real-time monitoring of the temperature sensor, the temperature of the heat transfer oil in the cavity 11 is stably controlled within the target range required by the process.

[0048] Furthermore, when the difference between the upper temperature T1 detected by the upper temperature sensor 21 and the lower temperature T2 detected by the lower temperature sensor 31 satisfies: T1-T2≤2℃; then the heating rod 32 in the lower cover 3 is driven to heat the heat transfer oil in the oil inlet pipe 5 of the cold oil tank 42 pump. During this stage, the temperature of the heat transfer oil will change over time and with external environmental factors. To ensure the stable operation of the entire ultra-high pressure isostatic pressing device, it is necessary to continuously monitor and fine-tune the temperature of the heat transfer oil in chamber 11. The working state of the heating rod 32 can be dynamically adjusted based on the real-time temperature data fed back by the upper temperature sensor 21 and the lower temperature sensor 31. If the difference between the upper temperature T1 and the lower temperature T2 is detected to exceed 2°C again, the heating rod 32 in the lower cover 3 is restarted to heat the heat transfer oil in the oil inlet pipe 5, so that the temperature difference between the upper and lower layers T2 is kept within a reasonable range.

[0049] Step S4: Maintain the electromagnetic induction coil 12 so that the temperature of the heat transfer oil in the cavity 11 reaches the set value T. At the same time, adjust the power of the electromagnetic induction coil 12 and turn off the oil pump of the booster system 421 so that the heat transfer oil in the cavity 11 enters the pressure holding stage. Step S5: After the pressure holding stage, turn off the electromagnetic induction coil 12 and allow the heat transfer oil in the cavity 11 to enter the pressure relief stage. After the pressure relief stage, remove the powder or product from the cavity 11.

[0050] Other aspects that are the same as in Example 1 will not be repeated in this example.

[0051] It is noteworthy that those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0052] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, as well as combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0053] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0054] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0055] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

[0056] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus.

[0057] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An ultra-high pressure vessel, comprising a cylindrical body (1) and an upper cover (2) and a lower cover (3) disposed on both sides of a cavity (11) in the height direction of the cylindrical body (1), wherein the cavity (11) is used to assemble powder or product to be pressurized, and the upper cover (2) and the lower cover (3) are respectively connected to a medium oil tank (4), characterized in that, The medium oil tank (4) is connected to an oil inlet pipe (5) and an oil return pipe (43). The oil inlet pipe (5) is connected to the lower cover (3), and the heat transfer oil in the medium oil tank (4) is pumped into the cavity (11) through the oil inlet pipe (5); the heat transfer oil flows back from the cavity (11) to the medium oil tank (4) through the oil return pipe (43). An electromagnetic induction coil (12) is provided on the outside of the cylinder (1), and the electromagnetic induction coil (12) is used to heat the heat-conducting oil in the cavity (11); An upper temperature sensor (21) is provided in the upper cover (2), and the upper temperature sensor (21) is used to detect the temperature of the heat-conducting oil in the cavity (11) near the upper cover (2); a lower temperature sensor (31) is provided in the lower cover (3), and the lower temperature sensor (31) is used to detect the temperature of the heat-conducting oil in the cavity (11) near the lower cover (3).

2. The ultra-high pressure vessel according to claim 1, characterized in that, The medium oil tank (4) is equipped with a hot oil tank (41), and the hot oil tank (41) is equipped with a heating component. The heating component is used to heat the heat transfer oil in the hot oil tank (41) or the heat transfer oil flowing into the hot oil tank (41) from the return oil pipe (43) to the preset process temperature. A circulation system (411) is connected between the hot oil tank (41) and the oil inlet pipe (5). The circulation system pumps the heat transfer oil into the cavity (11) through an oil pump.

3. The ultra-high pressure vessel according to claim 1, characterized in that, A cold oil tank (42) is provided inside the medium oil tank (4). The cold oil tank (42) is used to store the cooled heat transfer oil. A booster system (421) and a heater (4212) are connected between the cold oil tank (42) and the oil inlet pipe (5). The booster system (421) pumps the heat transfer oil into the cavity (11) through an oil pump. The heater (4212) heats the heat transfer oil pumped by the booster system (421).

4. The ultra-high pressure vessel according to claim 3, characterized in that, The cold oil tank (42) is connected to the oil inlet pipe (5) by a pressure relief pipe (422), and a first pressure relief valve (4221) is provided in the pressure relief pipe (422).

5. An ultra-high pressure vessel according to claim 1, characterized in that, The lower cover (3) is provided with a heating rod (32), which is used to heat the heat-conducting oil in the oil inlet pipe (5).

6. The ultra-high pressure vessel according to claim 1, characterized in that, The electromagnetic induction coil (12) and the cylinder (1) are provided with a steel strip winding layer (13) and a heat insulation layer (14). The steel strip winding layer (13) is located on the outside of the cylinder (1), and the heat insulation layer (14) is located on the outside of the steel strip winding layer (13).

7. An ultra-high pressure vessel according to claim 6, characterized in that, The electromagnetic induction coil (12) is provided with a protective layer (15) on its outer side.

8. The ultra-high pressure vessel according to claim 1, characterized in that, A second pressure relief valve (431) is installed inside the oil return pipeline (43).

9. A method for controlling the temperature of heat transfer oil inside an ultra-high pressure vessel as described in any one of claims 1-8, characterized in that, Includes the following steps: Step S1: Place the powder or product to be pressed into the cavity (11) of the cylinder (1) and set the set value T; Step S2: Preheat the heat transfer oil in the medium oil tank (4), pump the heat transfer oil into the cavity (11) through the oil inlet pipe (5), and turn on the electromagnetic induction coil (12) to heat the heat transfer oil in the cavity (11); Step S3: When the temperature of the heat transfer oil in the cavity (11) reaches T3 as detected by the upper temperature sensor (21) and / or the lower temperature sensor (31), the return oil pipe (43) is closed, and the heat transfer oil is pumped into the cavity (11) through the inlet oil pipe (5) to achieve pressurization; Step S4: Keep the electromagnetic induction coil (12) energized so that the temperature of the heat transfer oil in the cavity (11) reaches the set value T. At the same time, adjust the power of the electromagnetic induction coil (12) and close the oil inlet pipe (5) so that the heat transfer oil in the cavity (11) enters the pressure holding stage. Step S5: After the pressure holding stage, turn off the electromagnetic induction coil (12) to allow the heat transfer oil in the cavity (11) to enter the pressure relief stage. After the pressure relief stage, remove the powder or product from the cavity (11).

10. The method for controlling the temperature of heat transfer oil inside an ultra-high pressure vessel according to claim 9, characterized in that, In step S3, when the difference between the upper temperature T1 detected by the upper temperature sensor (21) and the lower temperature T2 detected by the lower temperature sensor (31) satisfies: T1-T2≤2℃, the heating rod (32) in the lower cover (3) is driven to heat the heat-conducting oil in the oil inlet pipe (5).

Images