Phase change cooling temperature control device of extruder

Abstract

The invention relates to the technical field of extruders, and discloses a phase change cooling temperature control device of an extruder, which comprises a heat pipe, and the heat pipe comprises a heat pipe condensation section, an evaporation section and a heat insulation section; the heat pipe evaporation section is located in the to-be-cooled structure and used for absorbing heat in the to-be-cooled structure so that an internal working medium can be converted into a gas state from a liquid state, and the gas state working medium flows into the heat pipe condensation section; and the cooling piece is arranged on the heat pipe condensation section and used for absorbing heat of a gaseous working medium in the heat pipe condensation section, converting the heat into a liquid state and enabling the liquid state to flow back to the heat pipe evaporation section. A phase change cooling temperature control device of an extruder is characterized in that a plurality of cooling ring sleeves are axially mounted on a barrel of the extruder, condensation sections of heat pipes are positioned in the cooling ring sleeves, evaporation sections of the heat pipes are positioned in the wall of the barrel of the extruder, and U-shaped heat pipes are of detachable structures and can be replaced with U-shaped heat pipes with different phase change temperatures according to different temperature control requirements. The heat conduction speed is high, efficiency is high, the temperature can be accurately controlled, and the product quality is improved.

Description

Technical Field

[0001] The invention relates to the technical field of extruders, in particular to a phase change cooling temperature control device of an extruder. Background Art

[0002] Extruder is the core equipment for mass production of plastic products with relatively simple structure. Temperature is one of the most important control factors in the extrusion process, which directly affects the melting state, fluidity, molding quality and final performance of the plastic. Therefore, according to the process requirements of the specific extrusion material, the barrel temperature is accurately controlled, usually set within 5-10℃ of the melting point of the material to ensure that the plastic can be evenly melted and smoothly injected into the mold, so as to produce high-quality, standard-compliant plastic products.

[0003] When the temperature of the extruder barrel is too high, it will cause problems such as material blockage, thermal decomposition, discoloration and even burning. At the same time, additives such as pigments and anti-washing modifiers may also undergo thermal decomposition during the melting process. These phenomena will lead to weakened mechanical properties of the product (due to shortened molecular chains), surface defects (caused by thermal decomposition) and may produce unpleasant odors. For the extruder itself, high temperature will also cause mechanical thermal deformation. Due to the different thermal expansion coefficients of various mechanical components, the matching clearance of moving parts may become smaller, and then stuck, affecting the transmission accuracy and reducing the work quality. In addition, excessively high temperatures will also deform plastic seals, accelerate their aging process, and eventually lead to leakage problems. At the same time, the increase in temperature will also affect the viscosity of the lubricating oil, reduce the volumetric efficiency of the pump and the efficiency of the entire hydraulic system, make the oil film of moving parts such as slide valves thinner, increase friction resistance, and thus aggravate wear.

[0004] If the extruder barrel temperature is too low, the product structure will be uneven and its impact resistance will be significantly weakened. At the same time, due to the low extruder temperature, the fluidity of the plastic melt will deteriorate, and it will not be able to fully fill the steam cavity in the mold. Defects may appear on the product surface, such as unevenness, uneven color, and even cracking. Due to insufficient plastic melt temperature, the product may not be cooled sufficiently or the molding time may be prolonged, thus affecting production efficiency and product quality. For the extruder itself, due to the poor fluidity of the plastic melt, it will cause blockage problems at the connection between the barrel and the screw. In addition, it may also cause abnormal mechanical properties of the extruded parts.

[0005] Therefore, precise temperature control of the barrel is very important. Most of the temperature control systems used in the prior art extruders are cooling systems (water cooling / air cooling) and heating systems (resistance heating / electromagnetic heating). The current temperature control strategy is relatively simple and direct, that is, when the temperature is detected to be lower than the set value, heating is started, and vice versa, cooling is started. This method has significant limitations in temperature control effect. Specifically, it faces problems such as obvious lag in control response, significant nonlinear characteristics of the system, and excessive adjustment (overshoot) that often occurs during temperature regulation.

[0006] Therefore, in actual production, the thermal coupling between the traditional cooling system and the heating system is not tight, making it difficult to maintain temperature uniformity, which may cause barrel temperature fluctuations and affect molding quality. At the same time, the heat absorbed by the cooling system eventually dissipates into the air and is not reasonably recycled, resulting in serious energy waste.

[0007] Among them, the blockage or scaling of the cooling water pipe in the water cooling system will reduce the heat transfer efficiency, and the failure of the cooling pump will cause uneven coolant flow. The air cooling system has high environmental requirements and relies on air circulation. The installation of fans and heat dissipation devices will take up a large space, affecting the spatial layout of the extruder.

[0008] Therefore, there is an urgent need for a phase change cooling temperature control device for an extruder to solve the above problems. Summary of the invention

[0009] The purpose of the present invention is to provide a phase change cooling temperature control device for an extruder to solve the problems existing in the above-mentioned prior art.

[0010] To achieve the above object, the present invention provides the following solution: The present invention provides a phase change cooling temperature control structure, comprising:

[0011] A heat pipe, the heat pipe comprising a heat pipe condensation section, a heat pipe evaporation section and a heat pipe insulation section;

[0012] The heat pipe evaporation section is located in the structure to be cooled, and is used to absorb the heat in the structure to be cooled so that the internal working medium is transformed from liquid to gas, and the gaseous working medium flows into the heat pipe condensation section;

[0013] The cooling element is arranged on the heat pipe condensation section, and is used to absorb the heat of the gaseous working medium in the heat pipe condensation section to convert the gaseous working medium into liquid and flow it back to the heat pipe evaporation section.

[0014] According to a phase change cooling temperature control structure provided by the present invention, the cooling component is a water-cooled component, and the water-cooled component includes a cooling water flow channel arranged in the cooling ring sleeve, and the two ends of the cooling water flow channel are respectively connected to one end of a water outlet pipe and a water inlet pipe, and the other ends of the water outlet pipe and the water inlet pipe are connected to a cooling tower.

[0015] According to a phase change cooling temperature control structure provided by the present invention, a steam chamber is provided in the heat pipe, and the pipe wall of the heat pipe is a porous capillary wick.

[0016] According to a phase change cooling temperature control structure provided by the present invention, a regulating valve is installed on the water inlet pipe.

[0017] According to a phase change cooling temperature control structure provided by the present invention, the heat pipe is a U-shaped pipe.

[0018] According to a phase change cooling temperature control structure provided by the present invention, the cooling component is an air cooling component, and the air cooling component includes a plurality of cooling fins, and the plurality of cooling fins are axially arranged in the condensation section. A cooling fan is installed on the cooling fins, and the cooling fan is driven by a servo motor.

[0019] A phase change cooling temperature control device for an extruder,

[0020] including an extruder barrel;

[0021] A plurality of cooling ring sleeves are axially mounted on the extruder barrel, the heat pipe condensation section is located in the cooling ring sleeve, and the heat pipe evaporation section is located in the barrel wall of the extruder barrel.

[0022] Compared with the prior art, the present invention has the following advantages and technical effects:

[0023] The present invention provides a phase change cooling and temperature control device for an extruder. The phase change cooling and temperature control device is used to cool and control the temperature of the extruder. The U-shaped heat pipe condensation section in the phase change cooling and temperature control device is cooled by a cooling member. The phase change cooling and temperature control device has fast heat conduction speed, high efficiency and significant energy saving effect. The working medium is composed of a liquid-gas-liquid closed loop. Heat is transferred by means of the phase change of the medium, which can achieve higher heat transfer efficiency and maximize the extraction of excess heat of the extruder. At the same time, the barrel temperature can be accurately controlled, the fluidity of the molten plastic and the filling effect of the injection can be optimized, the production cycle can be reduced, the production speed can be accelerated, and the overall production efficiency can be improved. At the same time, the high-precision temperature control of the phase change cooling of the extruder can avoid excessive heating or cooling, accurately adjust the temperature of the barrel, thereby reducing energy waste and cost investment, and also helps to improve the surface quality of the product and the uniformity of the internal structure, so that the quality of the product is more stable. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative labor:

[0025] Figure 1 This is a schematic diagram of the phase change cooling temperature control structure of the present invention;

[0026] Figure 2 It is a schematic diagram of the structure of the phase change cooling temperature control device of the present invention;

[0027] Figure 3 This is a structural diagram of Embodiment 2 of the present invention;

[0028] Figure 4 This is a structural diagram of Embodiment 3 of the present invention;

[0029] Figure 5 This is a schematic diagram of water cooling in Embodiment 3 of the present invention;

[0030] Figure 6 This is a schematic diagram of air cooling in Embodiment 3 of the present invention;

[0031] Among them, 1. cooling ring sleeve; 2. heat pipe condensation section; 3. heat pipe evaporation section; 4. heat pipe insulation section; 5. extruder barrel; 6. cooling tower; 7. water outlet pipe; 8. regulating valve; 9. water inlet pipe; 10. servo motor; 11. cooling fan; 12. cooling fins; 13. heat spreader; 14. fixed bracket. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. 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 creative work are within the scope of protection of the present invention.

[0033] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0034] Embodiment 1:

[0035] Reference Figure 1-Figure 2 The present invention provides a phase change cooling temperature control structure, comprising:

[0036] The heat pipe comprises a heat pipe condensation section 2, a heat pipe evaporation section 3 and a heat pipe insulation section 4;

[0037] The heat pipe evaporation section 3 is located in the structure to be cooled, and is used to absorb the heat in the structure to be cooled so that the internal working medium is transformed from liquid to gas, and the gaseous working medium flows into the heat pipe condensation section 2;

[0038] The cooling element is arranged on the heat pipe condensation section 2 and is used to absorb the heat of the gaseous working medium in the heat pipe condensation section 2 to convert it into liquid and flow it back to the heat pipe evaporation section 3.

[0039] As an optional embodiment, the cooling element is a water-cooled element, which includes a cooling water flow channel arranged in a cooling ring sleeve 1, and the two ends of the cooling water flow channel are respectively connected to one end of a water outlet pipe 7 and a water inlet pipe 9, and the other ends of the water outlet pipe 7 and the water inlet pipe 9 are connected to a cooling tower 6.

[0040] In one embodiment of the present invention, referring to Figure 2 The U-shaped heat pipe condensation section 2 in the phase change cooling temperature control device is connected to the cooling ring 1, and the heat is transferred from the U-shaped heat pipe condensation section 2 to the cooling ring 1 and then taken away by the cooling water in the cooling water flow channel.

[0041] As an optional implementation, the cooling water flow channel is a loop flow channel to ensure the heat dissipation effect.

[0042] As an optional implementation, a steam chamber is provided in the heat pipe, and the wall of the heat pipe is a porous capillary wick.

[0043] As an optional implementation, a regulating valve 8 is installed on the water inlet pipe 9 .

[0044] In one embodiment of the present invention, the cooling water flow rate is regulated by a regulating valve 8 .

[0045] As an optional implementation, the heat pipe is a U-shaped pipe.

[0046] As an optional embodiment, the cooling element is an air-cooled element, which includes a plurality of heat sink fins 12 , which are axially arranged in the heat pipe condensation section 2 , and a heat sink fan 11 is installed on the heat sink fins 12 , and the heat sink fan 11 is driven by a servo motor 10 .

[0047] A phase change cooling temperature control device for an extruder,

[0048] comprising an extruder barrel 5;

[0049] A plurality of cooling ring sleeves 1 are axially mounted on the extruder barrel 5 .

[0050] The U-shaped heat pipe evaporation section 3 in the phase change cooling temperature control structure is connected to the extruder barrel 5, the U-shaped heat pipe condensation section 2 is installed in the cooling ring sleeve 1, and the multiple water outlet pipes 7 and water inlet pipes 9 share the same cooling tower 6.

[0051] In one embodiment of the present invention, referring to Figure 2Based on the principle of the phase change cooling temperature control device, first, the heat transferred from the material to the extruder barrel 5 is absorbed by the U-shaped heat pipe in the phase change cooling temperature control device, and the working medium undergoes a phase change in the U-shaped heat pipe evaporation section 3. Since the working medium temperature remains unchanged during evaporation, stable temperature control can be achieved. Then, the vaporized working medium flows through the U-shaped heat pipe internal channel through the U-shaped heat pipe insulation section 4 and finally reaches the U-shaped heat pipe condensation section 2. The condensation section is connected to the cooling ring 1. The heat is transferred from the U-shaped heat pipe condensation section 2 to the cooling ring 1 and then taken away by the cooling water in the cooling water flow channel. After the working medium in the U-shaped heat pipe condensation section 2 is condensed into liquid, it returns to the U-shaped heat pipe evaporation section 3 to continue absorbing heat and perform the above-mentioned cycle process to achieve the purpose of heat dissipation.

[0052] Cooling water circulation: The cold water in the cooling tower 6 flows into the cooling water flow channel in the cooling ring 1 through the water inlet pipe 9, absorbs the heat in the cooling ring 1 through convection heat transfer, and then flows back into the cooling tower 6 through the water outlet pipe 7. The flow rate of the cooling water can be controlled by controlling the opening and closing degree of the regulating valve 8, thereby controlling the rate at which the working medium in the U-shaped heat pipe condensation section 2 in the phase change cooling temperature control device condenses and flows back to the U-shaped heat pipe evaporation section 3.

[0053] Embodiment 2:

[0054] Reference Figure 3 As an optional embodiment, the cooling element is an air-cooled element, which includes a plurality of heat sink fins 12, and the plurality of heat sink fins 12 are connected to the heat pipe condensation section 2 of the phase change cooling temperature control device. A heat sink fan 11 is installed on the heat sink fins 12, and the heat sink fan 11 is driven by a servo motor 10.

[0055] In one embodiment of the present invention, referring to Figure 3 , the heat dissipation method of the U-shaped heat pipe condensation section 2 of the phase change cooling temperature control device can be replaced by air cooling. That is, heat dissipation fins 12 are added to the U-shaped heat pipe condensation section 2 of the phase change cooling temperature control device, and the heat dissipation of the U-shaped heat pipe condensation section 2 is controlled by adjusting the power of the heat dissipation fan 11. Compared with air-cooled phase change cooling temperature control, the phase change temperature control that relies on water cooling has higher heat dissipation efficiency, but its manufacturing process is complex and the maintenance cost is high. Although air cooling has lower cost, its heat dissipation efficiency is also low. In a working environment where the heat dissipation efficiency requirement is not high, air cooling can be used instead of water cooling to achieve the purpose of cost saving.

[0056] Based on the working principle of the phase change cooling temperature control device, the heat transferred from the material to the extruder barrel 5 is absorbed by the phase change cooling temperature control device, and the working medium undergoes phase change in the U-shaped heat pipe evaporation section 3. Since the working medium temperature remains unchanged during evaporation, stable temperature control can be achieved. The vaporized working medium flows through the internal channel of the U-shaped heat pipe to the U-shaped heat pipe condensation section 2. The U-shaped heat pipe condensation section 2 is connected to the heat dissipation fins 12. The heat is transferred from the U-shaped heat pipe condensation section 2 to the heat dissipation fins 12, and the heat on the heat dissipation fins 12 is diffused to the outside through the heat dissipation fan 11. After the working medium in the U-shaped heat pipe is condensed into liquid, it returns to the U-shaped heat pipe evaporation section 3 to continue absorbing heat and perform the above cycle process to achieve the purpose of heat dissipation.

[0057] The U-shaped heat pipe condensing section 2 in the phase change cooling temperature control device of the present invention can adopt dry-wet combined cooling, first using a dry cooler (blowing cold air into the flow channel in the cooling ring sleeve) to reduce the temperature to a certain level, and then further cooling it through a wet cooler (cold water flows through the flow channel in the cooling ring sleeve).

[0058] The U-shaped heat pipe condensation section 2 in the phase change cooling temperature control device can also be directly air-cooled to transfer heat to the surrounding cold air through spontaneous heat dissipation.

[0059] Example 3: Reference Figure 4 , Figure 5 , Figure 6 As an optional implementation, the U-shaped heat pipe in the phase change cooling temperature control device can be replaced by a heat spreader 13. The heat spreader is installed on the outside of the barrel through a fixed bracket 14 (with a cooling water flow channel inside). The inner side close to the barrel is the evaporation zone, and the outer side away from the barrel is the condensation zone. The waste heat generated by the barrel is absorbed by the coolant in the evaporation zone, and then the coolant vaporizes. When the vaporized coolant touches the colder condensation zone, it will re-condense into liquid coolant, and the coolant will return to the evaporation zone with the help of the capillary channel in the heat spreader. This example can dissipate heat to the outside of the heat spreader in the way of Example 1 and Example 2, such as Figure 5 (Water Cooling), Figure 6 (Air cooling). This process is repeated over and over again to achieve the purpose of heat dissipation.

[0060] The phase change cooling temperature control device of the present invention has a fast heat transfer speed, high efficiency and significant energy saving effect. The heat transfer of the phase change cooling temperature control device increases with the increase of temperature difference. The working medium forms a closed loop of liquid-gas-liquid, so that heat can be transferred by means of the phase change of the medium, so that a higher heat transfer efficiency can be achieved, and the excess heat of the extruder can be exported to the greatest extent, which is convenient for recycling in the next step.

[0061] The extruder uses phase change cooling temperature control, which can accurately control the barrel temperature, optimize the fluidity of the molten plastic, and the filling effect of the injection, reduce the production cycle, speed up the production speed, and improve the overall production efficiency. At the same time, the high-precision temperature control of the extruder phase change cooling can avoid excessive heating or cooling, accurately adjust the temperature of the barrel, thereby reducing energy waste and cost investment. Accurate temperature control also helps to improve the surface quality of the product and the uniformity of the internal structure, making the product quality more stable.

[0062] The phase change cooling and temperature control device has a wide applicable temperature range and high flexibility. At present, the temperature range that the phase change cooling and temperature control device can adapt to can reach -200 to 2000℃. (The working fluid and the pipe wall material have different properties, and the use temperature is also different.) The application of the phase change cooling and temperature control device is not limited by the type of heat source. The evaporation section and condensation section of the U-shaped heat pipe can also be made into various shapes, and can also be made into a flexible phase change cooling and temperature control device. The structure is flexible and changeable, which can achieve close fit with the application equipment, occupies little space, and is suitable for various types of plastic processing equipment.

[0063] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0064] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A phase change cooling temperature control structure, characterized in that: include: A heat pipe, the heat pipe comprising a heat pipe condensation section (2), a heat pipe evaporation section (3) and a heat pipe insulation section (4); The heat pipe evaporation section (3) is located in the structure to be cooled, and is used to absorb heat in the structure to be cooled so that the internal working medium is transformed from liquid to gas, and the gaseous working medium flows into the heat pipe condensation section (2); A cooling element is arranged on the heat pipe condensation section (2), and is used to absorb the heat of the gaseous working medium in the heat pipe condensation section (2) to convert the gaseous working medium into liquid and flow it back to the heat pipe evaporation section (3).

2. A phase change cooling temperature control structure according to claim 1, characterized in that: The cooling element is a water-cooling element, and the water-cooling element includes a cooling water flow channel arranged in the cooling ring sleeve (1), and the two ends of the cooling water flow channel are respectively connected to an outlet pipe (7) and one end of a water inlet pipe (9), and the other ends of the outlet pipe (7) and the water inlet pipe (9) are connected to a cooling tower (6).

3. A phase change cooling temperature control structure according to claim 1, characterized in that: A steam chamber is arranged in the heat pipe, and the pipe wall of the heat pipe is a porous capillary wick.

4. A phase change cooling temperature control structure according to claim 2, characterized in that: A regulating valve (8) is installed on the water inlet pipe (9).

5. A phase change cooling temperature control structure according to claim 2, characterized in that: The heat pipe is a U-shaped pipe.

6. A phase change cooling temperature control structure according to claim 1, characterized in that: The cooling element is an air-cooling element, and the air-cooling element comprises a plurality of heat dissipation fins (12). The plurality of heat dissipation fins (12) are axially arranged in the condensation section (2). A heat dissipation fan (11) is installed on the heat dissipation fins (12), and the heat dissipation fan (11) is driven by a servo motor (10).

7. A phase change cooling temperature control device for an extruder, characterized in that: comprising an extruder barrel (5); A phase change cooling temperature control structure as described in any one of claims 1 to 6, wherein a plurality of cooling ring sleeves (1) are axially installed on the extruder barrel (5), the heat pipe condensation section (2) is located in the cooling ring sleeve (1), and the heat pipe evaporation section (3) is located in the barrel wall of the extruder barrel (5).

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