A modular heating and sealing mold cavity with multi-zone temperature control and temperature field uniformity

Abstract

This invention provides a modular heating and sealing mold cavity with multi-zone temperature control and temperature field homogenization. By employing multi-zone independent heaters on the outer periphery of the molding cylinder and combining them with multi-point temperature acquisition elements for closed-loop control, the temperature difference between the upper and lower parts of the cylinder can be effectively eliminated, achieving temperature field homogenization and precise control, significantly improving the consistency of the density and carbonization degree of the molded body. The replaceable liner allows for rapid adaptation of the cavity structure to the sample. For different sample sizes, materials, and surface requirements, only a lower-cost liner needs to be replaced without replacing the entire expensive molding cylinder, greatly reducing the modification and maintenance costs for switching test conditions. Furthermore, the external heat insulation and reflective layers effectively reduce heat loss, lower energy consumption and heating time, and improve test efficiency. This structure is also compatible with existing piston dynamic sealing and pressure monitoring sealing structures, forming a complete, high-performance test mold cavity.

Description

Technical Field

[0001] This invention relates to the field of material carbonization molding technology, and in particular to a modular heating and sealing mold cavity with multi-zone temperature control and temperature field uniformity. Background Technology

[0002] Material carbonization or pyrolysis processes typically require high-temperature, sealed environments to promote the thermal decomposition of organic matter, generating target char products and small-molecule gases. The heated, sealed mold cavity, as the core component providing this high-temperature, sealed environment, directly determines the quality of the carbonization molding and the reliability of the test results. In existing technologies, common heated, sealed mold cavities often employ a single cylindrical structure, combined with a top cover and pressure head to form the molding space. For example, a typical cylinder is machined from 2316 mold steel, with the molding space designed to have fixed dimensions (e.g., 50mm diameter, 150mm height). To ensure dynamic sealing in the high-temperature environment, existing technologies also employ sealing structures such as a piston dynamic seal with a rotating plug and graphite ring, and a pressure monitoring sealing structure including a force-transmitting sealing ring and a heat insulation plate, to address the issue of piston movement and the inability of load sensors to directly contact the high-temperature environment.

[0003] However, in practical applications, the existing heated sealing mold cavity structure still has the following technical problems: First, due to the relatively simple heating method (such as setting a single-stage heater only on the outer periphery of the cylinder), a significant temperature gradient is easily generated along the height of the cylinder, resulting in a large temperature difference between the top and bottom of the cylinder. This uneven temperature field directly causes uneven density distribution and inconsistent carbonization degree of the molded body, seriously affecting the performance of the final product. Second, existing devices mostly adopt a single-point temperature control method, that is, controlling the temperature of the entire cavity through only one temperature measuring point. This method is difficult to accurately reflect the actual temperature inside the sample and at different locations within the cavity, resulting in a large control error and failing to meet the requirements of precision tests with high temperature field uniformity. Furthermore, the inner diameter and height of the existing cavity are usually fixed. When it is necessary to process samples of different sizes and materials or to change the liner with different surface conditions, it is often necessary to replace the entire molding cylinder. The structural replacement cost is high and the operation is cumbersome, making it impossible to achieve rapid and low-cost switching of test conditions. Therefore, how to achieve uniformity and controllability of the cavity temperature field while maintaining a high-temperature sealed and molded spatial structure, and how to reduce the modification and maintenance costs under different test conditions through structural improvements, are technical problems that urgently need to be solved by those skilled in the art. Summary of the Invention

[0004] The purpose of this invention is to provide a modular heating and sealing mold cavity with multi-zone temperature control and temperature field uniformity to solve the problems existing in the prior art.

[0005] To achieve the above objectives, the present invention provides the following solution: This invention provides a modular heating and sealing mold cavity with multi-zone temperature control and temperature field uniformity, including a molding cylinder, a replaceable liner, a multi-zone heater, a multi-point temperature acquisition element, a controller, a heat insulation layer, and a reflective layer. The replaceable liner is detachably disposed inside the molding cylinder. The multi-zone heater is disposed on the outer periphery of the molding cylinder. The multi-point temperature acquisition element is disposed at different height positions of the molding cylinder and close to the inner wall of the molding cylinder. The controller is electrically connected to the multi-zone heater and the multi-point temperature acquisition element respectively. The heat insulation layer wraps around the outside of the multi-zone heater, and the reflective layer is disposed outside the heat insulation layer. The multi-zone heater includes independently controlled heating zones, which are upper and lower heating zones arranged along the axial direction of the formed cylinder, or upper, middle and lower heating zones. Each heating zone is independently selected from resistance heating coils, heating strips or embedded heating rods. Each heating zone corresponds to at least one multi-point temperature acquisition element, which is a thermocouple or an embedded temperature sensing element. The controller is equipped with a solid-state relay and a multi-functional operation module for real-time monitoring and programmable setting of heating temperature and time parameters. The controller implements closed-loop control of each heating zone based on the actual temperature acquired by the multi-point temperature acquisition element.

[0006] Preferably, the molded cylinder is made of 2316 mold steel or equivalent heat-resistant mold steel, the replaceable liner is made of wear-resistant and heat-resistant material, and a micro gap is formed between the replaceable liner and the inner wall of the molded cylinder or a heat-conducting medium layer is filled therein.

[0007] Preferably, the heated sealing mold cavity further includes a dynamic sealing structure, which includes a hollow plug and a graphite ring. The hollow plug is threadedly connected to the molding cylinder, and the graphite ring is disposed in the space in front of the hollow plug. By rotating the hollow plug, the graphite ring is made to fit tightly against the piston rod to achieve dynamic sealing under high temperature conditions.

[0008] Preferably, the heated sealing mold cavity further includes a pressure monitoring and sealing structure, which includes a force-transmitting sealing ring, a force-transmitting sealing plug, a heat insulation plate, and a fixing plate. The force-transmitting sealing ring is sealed to the molding cylinder by a graphite gasket. The force-transmitting sealing plug passes through the force-transmitting sealing ring and is movable relative to it. The force-transmitting sealing plug and the force-transmitting sealing ring are sealed by a multi-layer U-shaped fluororubber sealing ring. The heat insulation plate is disposed between the force-transmitting sealing plug and the load sensor. The fixing plate is used to fix the load sensor.

[0009] Preferably, the heated and sealed mold cavity further includes a top cover and a pressure head, and the top cover, pressure head and the molding cylinder are sealed together to form a material molding space.

[0010] Preferably, the heat insulation layer is a heat insulation material layer, and the reflective layer is a metal reflective layer.

[0011] The present invention achieves the following beneficial technical effects compared to the prior art: This invention provides a modular heating and sealing mold cavity with multi-zone temperature control and temperature field homogenization. By employing multi-zone independent heaters on the outer periphery of the molded cylinder and combining them with multi-point temperature acquisition elements for closed-loop control, it can effectively eliminate the temperature difference between the upper and lower parts of the cylinder, achieving temperature field homogenization and precise control, and significantly improving the consistency of the density and carbonization degree of the molded body. At the same time, by setting a replaceable liner, it can achieve rapid adaptation of the cavity structure to the sample. For different sample sizes, materials and surface requirements, only the lower-cost liner needs to be replaced without replacing the entire expensive molded cylinder, which greatly reduces the modification and maintenance costs of switching test conditions. In addition, with the external heat insulation layer and reflective layer, heat loss is effectively reduced, energy consumption and heating time are reduced, and test efficiency is improved. Moreover, this structure can be compatible with existing piston dynamic sealing and pressure monitoring sealing structures to form a complete, high-performance test mold cavity. Attached Figure Description

[0012] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0013] Figure 1 A schematic diagram of the modular heating and sealing mold cavity structure for multi-zone temperature control and temperature field uniformity provided by the present invention. Detailed Implementation

[0014] Unless otherwise specified, the terms "connection" and "linkage" used in this application include both direct and indirect connections (linkages). In the description of this invention, it should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention.

[0015] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0016] 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.

[0017] The purpose of this invention is to provide a modular heating and sealing mold cavity with multi-zone temperature control and temperature field uniformity, which aims to solve the technical problems of uneven temperature field, low temperature control accuracy and high operating condition switching cost in the prior art.

[0018] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0019] Example 1: like Figure 1 As shown, the present invention provides a modular heating and sealing mold cavity with multi-zone temperature control and temperature field homogenization, including a molding cylinder 1 serving as the overall support and molding body. The molding cylinder 1 is preferably made of 2316 mold steel or equivalent heat-resistant mold steel to withstand the harsh working environment of high temperature and high pressure. To flexibly adapt to samples of different sizes and materials and reduce replacement costs, a replaceable liner is detachably installed inside the molding cylinder. This replaceable liner is made of wear-resistant and heat-resistant material (such as heat-resistant stainless steel or special ceramics), and in actual operation, liners with different inner diameters or surface conditions can be quickly replaced according to test requirements. To ensure efficient heat transfer, a micro-gap can be formed between the replaceable liner and the inner wall of the molding cylinder for easy disassembly and assembly, or a thermally conductive medium layer (such as thermally conductive graphite foil) can be filled to reduce contact thermal resistance.

[0020] To address the issue of large temperature gradients along the height of the cylinder in existing technologies, this invention incorporates a multi-zone heater 2 on the outer periphery of the forming cylinder. This multi-zone heater 2 includes at least two independently controlled heating zones. In a preferred embodiment, the heating zones can be an upper heating zone and a lower heating zone arranged axially along the forming cylinder. For applications requiring higher temperature uniformity, it can be further subdivided into upper, middle, and lower heating zones. Each heating zone can be independently selected from resistance heating coils, heating strips, or embedded heating rods to achieve flexible heat supply. Correspondingly, this invention provides multi-point temperature acquisition elements at different height positions of the forming cylinder, near the inner wall. Each heating zone corresponds to at least one temperature acquisition point; these temperature acquisition elements can be thermocouples or embedded temperature sensing elements. By electrically connecting the controller to both the multi-zone heater and the multi-point temperature acquisition elements, the controller can implement independent closed-loop control of the output power of each heating zone based on the actual temperature feedback from the multi-point temperature acquisition elements. For example, when the temperature detected by the upper temperature acquisition point is lower than the set value, the controller will increase the heating power of the upper heating zone, and vice versa, thereby accurately eliminating the temperature difference between the upper and lower parts and achieving uniformity of the temperature field.

[0021] To reduce heat loss to the environment, lower energy consumption, and shorten heating time, the multi-zone heater of this invention is further wrapped with a heat insulation layer made of a low thermal conductivity insulation material (such as ceramic fiber or aerogel felt). Outside the heat insulation layer, a reflective layer is further provided, preferably a metal reflective layer (such as polished aluminum foil or stainless steel sheet), which can reflect some of the radiant heat back into the cavity, further improving thermal efficiency.

[0022] In a further preferred embodiment of the present invention, to solve the dynamic sealing problem caused by frequent piston rod movement under high temperature conditions, the heated sealing mold cavity also integrates a dynamic sealing structure 3. Specifically, this dynamic sealing structure includes a hollow plug 31 and a graphite ring 32. The hollow plug 31 is threadedly connected to the molding cylinder, and the graphite ring 32 is disposed in the space reserved in front of the hollow plug. During operation, by rotating the hollow plug 31, it moves axially and compresses the graphite ring 32, thereby making the graphite ring 32 tightly fit against the outer wall of the piston rod. Graphite has excellent high temperature resistance and self-lubricating properties, which can form a reliable dynamic seal at high temperatures, and wear can be compensated by further tightening the hollow plug.

[0023] On the other hand, in order to accurately measure the pressure applied to the sample under high temperature conditions and avoid damage to the load sensor due to high temperature, the present invention also integrates a pressure monitoring sealing structure 4. This structure includes a force-transmitting sealing ring 41, a force-transmitting sealing plug 42, a heat insulation plate 43, and a fixing plate 44. The force-transmitting sealing ring 41 and the molding cylinder 1 are statically sealed by a graphite gasket 45. The force-transmitting sealing plug 42 passes through the force-transmitting sealing ring 41, and the two can move relative to each other. In order to achieve the sealing of this dynamic contact surface, a multi-layer U-shaped fluororubber sealing ring 46 is provided between the force-transmitting sealing plug 42 and the force-transmitting sealing ring 41. During the test, the pressure on the sample is transmitted upward through the force-transmitting sealing plug 42. In order to block the upward transmission of heat to the load sensor, a heat insulation plate 43 is provided between the force-transmitting sealing plug 42 and the load sensor. The heat insulation plate 43 is made of a material with extremely low thermal conductivity and high compressive strength (such as a composite material of glass fiber and resin). Finally, to avoid stress concentration and ensure structural stability, the load sensor is fixed by the fixing plate 44, so that the force measuring structure in the middle of the load sensor makes smooth contact with the heat insulation pad, thereby realizing accurate measurement of the pressure on the material under high temperature vibration load.

[0024] In terms of overall structural assembly, this heated and sealed mold cavity also includes a top cover and a pressure head. The top cover, pressure head, and molding cylinder are connected by a sealing assembly (such as a graphite sealing ring) to form a closed and precisely dimensional material molding space. In a specific application example, considering the compressibility of the material (such as pulverized coal), the molding space inside the molding cylinder is preferably 50mm in diameter and 150mm in height. Furthermore, to achieve precise automated control of the testing process, the controller is equipped with a solid-state relay and integrates a multi-functional operation module. This module, through a digital display interface, enables real-time monitoring and programmable setting of parameters such as multi-zone heating temperature, holding time, and heating / cooling rates. Operators can conveniently set and monitor the entire hot-pressing molding process.

[0025] The invention will be further described below with reference to a complete operating procedure. First, a suitable replaceable liner is selected according to the size of the sample required for the test and installed inside the molding cylinder. Then, the biomass raw material or coal powder to be processed is filled into the molding space defined by the liner, top cover, and pressure head. Next, the controller is started, and the target temperature and heating curve of the upper and lower heating zones are set according to the process requirements. The multi-zone heater starts working, and at the same time, the multi-point temperature acquisition element feeds back the temperature of each zone to the controller in real time. The controller precisely adjusts the power of each heating zone through solid-state relays, so that the internal temperature of the cavity rises rapidly and uniformly to the set value. During the heating process, a dynamic sealing structure ensures that gas does not leak out when the piston rod reciprocates, and a pressure monitoring sealing structure accurately transmits the applied pressure to the external load sensor. If the test is to be conducted in a protective atmosphere, nitrogen or argon can be introduced through the gas interface (not shown in the figure) connected to the cavity, and the generated exhaust gas is discharged to the external treatment system through the outlet. After the test, the cooling program is initiated via the controller (an external cooling device can be used). Once the temperature drops to a safe range, the top cover, pressure head, and related seals are disassembled in sequence, and finally the molded sample is removed. If tests of different sizes are required, only the replaceable liner of different specifications needs to be replaced, without replacing the entire molded cylinder, which significantly reduces testing costs and preparation time.

[0026] In summary, the specific embodiments provided by this invention, through modular cavity design, multi-zone independent heating and multi-point closed-loop temperature control technology, as well as integrated dynamic sealing and pressure monitoring sealing structures, effectively solve the problems of uneven temperature field, large temperature control error and high operating condition switching cost mentioned in the background technology, and achieve the effects of uniform temperature field, accurate temperature control, flexible operation and reliable sealing.

[0027] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0028] It should be noted that the components mentioned in the above embodiments are all general standard parts or components known to those skilled in the art. Their structures and principles can be learned by those skilled in the art through technical manuals or conventional experimental methods.

[0029] This invention has illustrated its principles and implementation methods using specific examples. The descriptions of these embodiments are merely illustrative of the method and its core ideas; furthermore, those skilled in the art will recognize that modifications may be made to the specific implementation methods and application scope based on the principles of this invention. Therefore, the content of this specification should not be construed as limiting the invention.

Claims

1. A modular heating and sealing mold cavity with multi-zone temperature control and temperature field uniformity, characterized in that, The device includes a molded cylinder, a replaceable liner, a multi-zone heater, a multi-point temperature acquisition element, a controller, a heat insulation layer, and a reflective layer. The replaceable liner is detachably disposed inside the molded cylinder. The multi-zone heater is disposed on the outer periphery of the molded cylinder. The multi-point temperature acquisition element is disposed at different height positions of the molded cylinder and close to the inner wall of the molded cylinder. The controller is electrically connected to the multi-zone heater and the multi-point temperature acquisition element respectively. The heat insulation layer wraps around the outside of the multi-zone heater, and the reflective layer is disposed outside the heat insulation layer. The multi-zone heater includes independently controlled heating zones, which are upper and lower heating zones arranged along the axial direction of the formed cylinder, or upper, middle and lower heating zones. Each heating zone is independently selected from resistance heating coils, heating strips or embedded heating rods. Each heating zone corresponds to at least one multi-point temperature acquisition element, which is a thermocouple or an embedded temperature sensing element. The controller is equipped with a solid-state relay and a multi-functional operation module for real-time monitoring and programmable setting of heating temperature and time parameters. The controller implements closed-loop control of each heating zone based on the actual temperature acquired by the multi-point temperature acquisition element.

2. The modular heating and sealing mold cavity with multi-zone temperature control and temperature field homogenization according to claim 1, characterized in that, The molded cylinder is made of 2316 mold steel or equivalent heat-resistant mold steel, and the replaceable liner is made of wear-resistant and heat-resistant material. The replaceable liner forms a micro gap with the inner wall of the molded cylinder or is filled with a heat-conducting medium layer.

3. The modular heating and sealing mold cavity with multi-zone temperature control and temperature field homogenization according to claim 1, characterized in that, The heated sealing mold cavity also includes a dynamic sealing structure, which includes a hollow plug and a graphite ring. The hollow plug is threadedly connected to the molding cylinder. The graphite ring is disposed in the space in front of the hollow plug. By rotating the hollow plug, the graphite ring is made to fit tightly against the piston rod to achieve dynamic sealing under high temperature conditions.

4. The modular heating and sealing mold cavity with multi-zone temperature control and temperature field homogenization according to claim 1, characterized in that, The heated and sealed mold cavity also includes a pressure monitoring and sealing structure, which includes a force-transmitting sealing ring, a force-transmitting sealing plug, a heat insulation plate, and a fixing plate. The force-transmitting sealing ring is sealed to the molding cylinder by a graphite gasket. The force-transmitting sealing plug passes through the force-transmitting sealing ring and can move relative to it. The force-transmitting sealing plug and the force-transmitting sealing ring are sealed by a multi-layer U-shaped fluororubber sealing ring. The heat insulation plate is disposed between the force-transmitting sealing plug and the load sensor. The fixing plate is used to fix the load sensor.

5. The modular heating and sealing mold cavity with multi-zone temperature control and temperature field homogenization according to claim 1, characterized in that, The heated and sealed mold cavity also includes a top cover and a pressure head, which are sealed together with the molding cylinder to form a material molding space.

6. The modular heating and sealing mold cavity with multi-zone temperature control and temperature field homogenization according to claim 1, characterized in that, The heat insulation layer is a heat insulation material layer, and the reflective layer is a metal reflective layer.

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