A CPP film cooling roll and an extrusion unit thereof

Abstract

The utility model relates to a kind of CPP film cooling roll and its extrusion unit, relate to film production technical field, including roll body, cooling space is opened along its axial direction in roll body, and the axial both ends of roll body are fixed by support ring, cooling assembly is arranged in cooling space, cooling assembly includes the cooling ring that abuts on the inner wall of roll body, circular ring baffle that cooling ring is separated into multiple cooling areas is fixedly arranged in cooling ring, liquid inlet connecting pipe that passes through the support ring of one end of roll body and is communicated with cooling area and liquid outlet connecting pipe that passes through the support ring of the other end of roll body and is communicated with cooling area, the utility model can pass through cooling assembly, reduce the cooling liquid temperature difference between inlet end and outlet end caused by the longer roll body, reduce the problem of cooling efficiency.

Description

Technical Field

[0001] This application relates to the field of film production technology, and in particular to a CPP film cooling roller and its extrusion unit. Background Technology

[0002] CPP (cast polypropylene film) is a non-stretched, non-oriented flat extruded film produced through a melt casting and rapid cooling process. It is mainly used in food packaging and daily necessities packaging. CPP film cooling rollers are key equipment in the polypropylene film production process, used for cooling and shaping the film. High-efficiency CPP film cooling rollers, through optimized cooling system design, improve cooling efficiency, ensuring rapid and uniform cooling of the film during production, thereby improving film quality and production efficiency.

[0003] In existing technologies, after the film is extruded or stretched, it is at a high temperature, typically exceeding 100°C to 200°C. To achieve ideal physical properties and dimensional stability, rapid and effective cooling is essential. The cooling roller is the core component of the entire cooling system. Current cooling methods involve introducing refrigerant into the cooling roller after film processing. The roller contacts the film, transferring heat from the film surface to the roller's surface. Subsequently, the refrigerant contacts the interior of the roller, exchanging heat and lowering the roller's surface temperature, thus cooling the film. However, the coolant enters the cooling roller from the inlet and flows along the length of the roller before exiting from the drain. This unidirectional flow design can usually meet basic cooling needs when dealing with shorter cooling rollers. When the cooling roller is longer, the coolant is at a lower temperature when it enters the roller and can effectively absorb the heat transferred from the roller and the film. As the coolant flows along the length of the roller, it continuously absorbs heat, causing the temperature to gradually rise. As the temperature of the coolant rises, the temperature difference between it and the roller decreases, and the heat exchange efficiency also decreases. This means that at the end of the cooling roller, the coolant can absorb less heat, resulting in a poorer cooling effect.

[0004] Therefore, it is necessary to propose a CPP film cooling roller and its extrusion unit to solve the above problems. Utility Model Content

[0005] This application provides a CPP film cooling roller and its extrusion unit. In order to improve the technical problem in the related technology that the unidirectional flow design causes the temperature of the refrigerant to gradually increase when the refrigerant flows from one end of the cooling roller to the other when facing a long cooling roller, which will eventually cause a large temperature difference between the two ends of the roller surface.

[0006] This application provides a CPP film cooling roller and its extrusion unit, including a roller body. The roller body has a cooling space along its axial direction, and both ends of the roller body are fixed by support rings. A cooling assembly is disposed within the cooling space. The cooling assembly includes a cooling ring abutting against the inner wall of the roller body. A circular partition is fixedly disposed inside the cooling ring, dividing the cooling ring into multiple cooling zones. An inlet connecting pipe passes through the support ring at one end of the roller body and communicates with the cooling zone, and an outlet connecting pipe passes through the support ring at the other end of the roller body and communicates with the cooling zone.

[0007] The technical solutions described above in this application embodiment have at least the following technical effects: During the cooling process of the film using the CPP film cooling roller, coolant is injected into the inlet connection pipe, and the coolant enters each cooling zone separated by the circular partition in the cooling ring through the inlet connection pipe. After the coolant is cooled, it enters the outlet connection pipe through the cooling ring and is then discharged. By diverting the coolant from the inlet connection pipe into each cooling zone and then merging the cooled inlet connection pipe into the outlet connection pipe for discharge, the temperature of the coolant in each cooling zone is the same, reducing the problem of reduced cooling efficiency caused by the temperature difference between the inlet and outlet ends of the coolant due to the long roller body.

[0008] In this embodiment, both the inlet connection pipe and the outlet connection pipe are provided with a heat insulation layer on their outer walls.

[0009] This technical solution involves installing insulation layers on the inlet and outlet connection pipes to reduce potential temperature interference between them. The insulation layer effectively minimizes heat exchange between the coolant and the external environment as the coolant flows through these pipes. This means the coolant can maintain a more stable temperature during transport, reducing temperature fluctuations caused by ambient temperature.

[0010] In this embodiment, the liquid inlet connection pipe is connected to the water inlet pipe of the refrigeration pump, and the liquid outlet connection pipe is connected to the water outlet pipe of the refrigeration pump.

[0011] This technical solution connects the inlet pipe to the refrigeration pump's inlet pipe and the outlet pipe to the refrigeration pump's outlet pipe, forming a closed-loop circulation system. This design ensures continuous circulation of coolant within the system, preventing reduced cooling efficiency due to coolant stagnation or poor flow. The refrigeration pump further enhances controllability of coolant flow, allowing for adjustments to flow rate and pressure as needed, thus achieving more precise temperature control.

[0012] In this embodiment, a rotating ring is provided on the support ring, a first ball is provided between the rotating ring and the support ring, the rotating ring is fixedly connected to the roller body, a connecting gear is provided on the outer wall of the rotating ring, and the connecting gear is driven by an external motor through a toothed belt.

[0013] With this technical solution, the rotation of the motor via the connecting gear and rotating ring does not affect the rotation of the inlet and outlet connecting pipes inside the internal support ring, thus reducing potential motion interference.

[0014] In this embodiment, a first flange is provided at both ends of the roller body along the axial direction, and a second flange is detachably connected to the first farad plate. The second farad plate is fixedly connected to the rotating ring.

[0015] This technical solution employs a detachable flange design, which facilitates maintenance in case of internal damage.

[0016] In this embodiment, a second ball bearing is arranged in an array between the inner wall of the roller body and the outer wall of the cooling ring.

[0017] With this technical solution, as the rotating ring drives the second farad to rotate, the roller body rotates, but the internal cooling ring does not rotate, thus reducing the impact of the potential energy of the refrigerant during rotation on the roller body's rotation efficiency.

[0018] In this embodiment, an extrusion unit includes a frame and a CPP film cooling roller. The frame has supports symmetrically arranged at both ends of the roller body along its axial direction. A motor is mounted on the frame to drive the roller body to rotate. The frame has two sets of cooling rollers with different heights. The two sets of cooling rollers rotate synchronously between each other via the motor. The two ends of the roller body are fixedly connected to the supports via support rings.

[0019] This technical solution allows cooling rollers of varying heights to create multi-layered cooling zones, enabling the film to undergo multiple cooling processes as it passes through the rollers. This multi-layered cooling design significantly enhances the cooling effect, ensuring the film reaches the required cooling temperature quickly, thereby improving production efficiency. Two sets of cooling rollers at different heights can cover a wider portion of the film surface, ensuring effective cooling at different locations. Synchronous rotation ensures the cooling rollers uniformly contact all parts of the film, preventing uneven cooling caused by uneven contact and improving overall cooling uniformity. Attached Figure Description

[0020] Figure 1 A three-dimensional structural schematic diagram of the CPP film cooling roller and its extrusion unit provided in the embodiments of this application; Figure 2Schematic cross-sectional structure of the thin film cooling roller provided in the embodiments of this application Figure 1 ; Figure 3 Schematic cross-sectional structure of the thin film cooling roller provided in the embodiments of this application Figure 2 ; Figure 4 for Figure 3 Enlarged view of point A in the middle; Figure 5 for Figure 3 Enlarged view of section B in the middle.

[0021] The following are the labeling elements in the figure: 1. Frame; 11. Support; 12. Roller body; 13. Motor; 14. Support ring; 2. Cooling assembly; 21. Cooling ring; 22. Circular partition; 23. Liquid inlet connection pipe; 24. Liquid outlet connection pipe; 25. Cooling zone; 3. Rotating ring; 31. First ball bearing; 32. Connecting gear; 33. First flange; 34. Second flange; 35. Second ball bearing. Detailed Implementation

[0022] In existing technologies, after the film is extruded or stretched, it is at a high temperature, typically exceeding 100°C to 200°C. To achieve ideal physical properties and dimensional stability, rapid and effective cooling is essential. The cooling roller is the core component of the entire cooling system. Current cooling methods involve introducing refrigerant into the cooling roller after film processing. The roller contacts the film, transferring heat from the film surface to the roller's surface. Subsequently, the refrigerant contacts the interior of the roller, exchanging heat and lowering the roller's surface temperature, thus cooling the film. However, the coolant enters the cooling roller from the inlet and flows along the length of the roller before exiting from the drain. This unidirectional flow design can usually meet basic cooling needs when dealing with shorter cooling rollers. When the cooling roller is longer, the coolant is at a lower temperature when it enters the roller and can effectively absorb the heat transferred from the roller and the film. As the coolant flows along the length of the roller, it continuously absorbs heat, causing the temperature to gradually rise. As the temperature of the coolant rises, the temperature difference between it and the roller decreases, and the heat exchange efficiency also decreases. This means that at the end of the cooling roller, the coolant can absorb less heat, resulting in a poorer cooling effect.

[0023] Based on this, in order to improve the technical problem in the related technology that the unidirectional flow design causes the temperature of the refrigerant to gradually increase when flowing from one end of the cooling roller to the other when facing a long cooling roller, resulting in a large temperature difference between the two ends of the roller surface, the embodiments of this application provide the following solution.

[0024] Please refer to the following: Figures 1 to 5 This application provides a CPP film cooling roller and its extrusion unit. The CPP film cooling roller and its extrusion unit include a roller body 12, a frame 1 at the bottom of the roller body 12, and supports 11 symmetrically arranged at both ends of the roller body 12 on the frame 1. A motor 13 is arranged on the frame 1 to drive the cooling roller to rotate. The roller body 12 has a cooling space along its axial direction. The two ends of the roller body 12 are fixedly connected to the supports 11 by support rings 14. A cooling assembly 2 is arranged in the cooling space. The cooling assembly 2 includes a cooling ring 21 that abuts against the inner wall of the roller body 12. A circular partition 22 is fixedly arranged inside the cooling ring 21 to divide the cooling ring 21 into multiple cooling areas 25. An inlet connecting pipe 23 passes through the support ring 14 at one end of the roller body 12 and communicates with the cooling area 25. An outlet connecting pipe 24 passes through the support ring 14 at the other end of the roller body 12 and communicates with the cooling area 25.

[0025] This application provides a CPP film cooling roller and its extrusion unit. During the cooling process of the film using the CPP film cooling roller, coolant is injected into the inlet connection pipe 23. The coolant then enters each cooling zone 25 separated by annular partitions 22 within the cooling ring 21 through the inlet connection pipe 23. After cooling, the coolant enters the outlet connection pipe 24 through the cooling ring 21 and is subsequently discharged. By diverting the coolant from the inlet connection pipe 23 into each cooling zone 25 and then recombining the cooled coolant from the inlet connection pipe 23 into the outlet connection pipe 24, the temperature of the coolant in each cooling zone 25 is made uniform. This reduces the problem of reduced cooling efficiency caused by the temperature difference between the inlet and outlet ends of the coolant due to the long roller body 12. Thus, by diverting the coolant into each cooling zone 25 and then recombining the cooled coolant into the outlet connection pipe 24, the uniform temperature of the coolant in each cooling zone 25 can be ensured. This uniform cooling effect can effectively avoid the temperature difference between the inlet and outlet of the coolant caused by the long length of the roller body 12, thereby ensuring that the film can be cooled consistently in all areas and avoiding the degradation of film quality caused by uneven temperature.

[0026] In this embodiment, both the inlet connection pipe 23 and the outlet connection pipe 24 are provided with a heat insulation layer on their outer walls.

[0027] With this configuration, an insulation layer is installed outside the inlet connection pipe 23 and the outlet connection pipe 24 to reduce the temperature interference that may occur between the inlet connection pipe 23 and the outlet connection pipe 24. The insulation layer can effectively reduce the heat exchange between the coolant and the external environment when the coolant flows in the inlet connection pipe 23 and the outlet connection pipe 24. This means that the coolant can maintain a more stable temperature during transportation and reduce the temperature fluctuation of the coolant caused by the influence of the external environment temperature.

[0028] In this embodiment, the liquid inlet connection pipe 23 is connected to the water inlet pipe of the refrigeration pump, and the liquid outlet connection pipe 24 is connected to the water outlet pipe of the refrigeration pump.

[0029] With this configuration, by connecting the inlet pipe 23 to the water inlet pipe of the refrigeration pump and the outlet pipe 24 to the water outlet pipe of the refrigeration pump, a closed circulation system can be formed. This design ensures that the coolant can continuously circulate in the system, avoiding a decrease in cooling efficiency due to coolant stagnation or poor flow.

[0030] In this embodiment, a rotating ring 3 is provided on the support ring 14, and a first ball bearing 31 is provided between the rotating ring 3 and the support ring 14. The rotating ring 3 is fixedly connected to the roller body 12. A connecting gear 32 is provided on the outer wall of the rotating ring 3, and the connecting gear 32 is driven by the motor 13 through a toothed belt.

[0031] With this configuration, the rotation of the motor 13 via the connecting gear 32 and the rotating ring 3 does not affect the rotation of the inlet connecting pipe 23 and the outlet connecting pipe 24 within the internal support ring 14, reducing potential motion interference. Since the inlet connecting pipe 23 and the outlet connecting pipe 24 do not rotate with the rotating ring 3, motion interference between these pipes and surrounding structures can be effectively avoided. If these pipes rotate with the rotating ring 3, they may collide or rub against other parts of the equipment, leading to equipment damage or pipe breakage. By keeping these pipes stationary, such motion interference can be reduced, improving the stability and reliability of the equipment.

[0032] In this embodiment, the roller body 12 is provided with a first flange at both ends of the axial direction, and a second flange 34 is detachably connected to the first farad 33. The second farad is fixedly connected to the rotating ring 3.

[0033] This design, featuring a detachable flange, facilitates repairs in case of internal damage. The detachable flange design also makes disassembling and replacing internal components much easier. When internal damage or malfunction occurs, the entire equipment does not need to be disassembled; simply removing the flange allows for quick access and repair of the damaged parts. This design significantly reduces maintenance time and improves equipment availability and production efficiency.

[0034] In this embodiment, a second ball bearing 35 is arranged in an array between the inner wall of the roller body 12 and the outer wall of the cooling ring 21.

[0035] This configuration ensures that while the rotating ring 3 drives the second farad plate to rotate, the roller body 12 rotates, but the internal cooling ring 21 does not. This reduces the impact of the potential energy generated by the rotating refrigerant on the rotation efficiency of the roller body 12. Furthermore, by rotating the roller body 12 without driving the internal cooling ring 21, the additional energy consumption caused by the rotation of the cooling ring 21 is reduced. The cooling ring 21 is typically filled with refrigerant; if it rotates with the roller body 12, it increases the moment of inertia, thus consuming more energy. By avoiding the rotation of the cooling ring 21, energy loss is reduced, and the rotation efficiency of the roller body 12 is improved.

[0036] In this embodiment, two sets of cooling rollers of different heights are provided on the frame 1, and the two sets of cooling rollers rotate synchronously through the motor 13.

[0037] This configuration allows cooling rollers of varying heights to create multi-layered cooling zones 25, enabling the film to undergo multiple cooling processes as it passes through the rollers. This multi-layered cooling design significantly enhances the cooling effect, ensuring the film reaches the required cooling temperature quickly, thereby improving production efficiency. The two sets of cooling rollers at different heights can cover a wider portion of the film surface, ensuring effective cooling at different locations. Synchronous rotation ensures the cooling rollers uniformly contact all parts of the film, preventing uneven cooling due to uneven contact and improving overall cooling uniformity.

[0038] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A CPP film cooling roll comprising a roll body (12), characterized in that: The roller body (12) has a cooling space along its axial direction. The two ends of the roller body (12) are fixed by support rings (14). A cooling assembly (2) is provided in the cooling space. The cooling assembly (2) includes a cooling ring (21) that abuts against the inner wall of the roller body (12). A circular partition (22) that divides the cooling ring (21) into multiple cooling areas (25) is fixedly provided inside the cooling ring (21). An inlet connection pipe (23) passes through the support ring (14) at one end of the roller body (12) and communicates with the cooling area (25). An outlet connection pipe (24) passes through the support ring (14) at the other end of the roller body (12) and communicates with the cooling area (25).

2. The CPP film cooling roll according to claim 1, characterized in that: Both the inlet connection pipe (23) and the outlet connection pipe (24) are provided with a heat insulation layer on their outer walls.

3. A CPP film cooling roller according to claim 2, characterized in that: The liquid inlet connection pipe (23) is connected to the water inlet pipe of the refrigeration pump, and the liquid outlet connection pipe (24) is connected to the water outlet pipe of the refrigeration pump.

4. A CPP film cooling roller according to claim 1, 2, or 3, characterized in that: A rotating ring (3) is provided on the support ring (14), and a first ball (31) is provided between the rotating ring (3) and the support ring (14). The rotating ring (3) is fixedly connected to the roller body (12). A connecting gear (32) is provided on the outer wall of the rotating ring (3), and the connecting gear (32) is driven by a toothed belt to an external motor.

5. A CPP film cooling roller according to claim 4, characterized in that: The roller body (12) is provided with a first flange (33) at both ends of the axial direction, and a second flange (34) is detachably connected to the first flange (33). The second flange (34) is fixedly connected to the rotating ring (3).

6. The CPP film cooling roll of claim 1 wherein: A second ball bearing (35) is arranged in an array between the inner wall of the roller body (12) and the outer wall of the cooling ring (21).

7. An extrusion unit, characterized by The device includes a frame (1) and a CPP film cooling roller as described in any one of claims 1 to 6. The frame (1) is provided with supports (11) symmetrically located at both ends of the roller body (12) in the axial direction. A motor (13) is provided on the frame (1) to drive the roller body (12) to rotate. Two sets of cooling rollers with different heights are provided on the frame (1). The two sets of cooling rollers rotate synchronously through the motor (13). The two ends of the roller body (12) in the axial direction are fixedly connected to the supports (11) respectively through support rings (14).

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