A kind of independent cooling anti-blocking device for screw granulator discharge port

Abstract

The utility model relates to screw granulator technical field discloses an independent cooling anti -blocking device for screw granulator discharge gate, and the granulator includes the base, first cylinder, second cylinder, screw core axle and discharge hopper, heat insulating plate is set up in the discharge gate between discharge hopper with first cylinder, the heat insulating plate inside integration has cooling runner, cooling runner is connected with external cooling system through pipeline joint, heat insulating pad is set up between the connecting interface of first cylinder with second cylinder. The utility model discloses a composite cooling system that heat insulating plate cooling runner and discharge gate cooling sleeve constitute, can carry out accurate, efficient forced heat exchange to the key area that the adhesion is most likely to occur, ensures that the area temperature is always lower than the softening point of material, and the arch bridge and the pole of holding phenomenon from the root are prevented from happening.

Description

Technical Field

[0001] This utility model relates to the field of screw granulator technology, specifically to an independent cooling and anti-clogging device for the feed inlet of a screw granulator. Background Technology

[0002] In the compounding and granulation process of polymer materials such as plastics and rubber, the twin-screw granulator is the core equipment. During operation, the material enters from the feed port, is conveyed, sheared, melted, and then extruded into granules by the screws. However, a common and thorny problem exists in actual production: due to the intense shearing heat generated at the root of the screw and the axial heat conduction from the high-temperature melting section (second cylinder), the temperature in the feed port area is often much higher than the softening point of the material. This causes the solid granules to melt prematurely at the feed port and in the first cylinder section connected to it before entering the melting section.

[0003] Pre-melted material will adhere to the relatively low-temperature cylinder wall and screw root, gradually accumulating and forming a "bridging" (material is suspended at the hopper outlet) or "screw-clamping" phenomenon. This not only seriously hinders the normal material conveying and leads to a decrease in production efficiency, but also causes frequent shutdowns for cleaning, affecting the continuity and stability of production, and ultimately threatening the consistency of product quality.

[0004] To address this issue, existing technologies typically employ two approaches: one is to reduce the overall set temperature of each zone of the granulator, but this significantly increases the heating energy consumption of the main melting section, reduces energy utilization, and may affect the final plasticizing effect; the other is to add a fan outside the feed port for forced convection cooling, but this method has low cooling efficiency, uneven effect, and cannot accurately control the temperature of key interfaces, making it difficult to fundamentally solve the adhesion and blockage problem caused by local overheating.

[0005] Therefore, there is an urgent need for a device that can accurately, efficiently, and independently control the temperature of the feed port area of ​​the granulator, so as to completely eliminate the risk of blockage at the feed port while ensuring the process temperature of the main melting zone. Utility Model Content

[0006] The purpose of this invention is to overcome the shortcomings of existing technologies and provide an independent cooling and anti-clogging device for the feed inlet of a screw granulator. This device can achieve precise localized strong cooling of the feed inlet and the feeding section, effectively isolating high-temperature heat conduction and ensuring that the material remains solid in the feeding section, thereby fundamentally preventing clogging problems caused by premature melting of the material.

[0007] This utility model proposes an independent cooling and anti-clogging device for the feed inlet of a screw granulator. The granulator includes a base, a first cylinder, a second cylinder, a screw mandrel, and a feed hopper. A heat insulation plate is disposed between the feed inlet of the feed hopper and the first cylinder. The heat insulation plate integrates cooling channels, which are connected to an external cooling system through pipe joints. A heat insulation pad is disposed between the connection interface of the first cylinder and the second cylinder. The cooling channels of the heat insulation plate remove heat from the key interface of the discharge port through forced heat exchange, precisely controlling the temperature in this area to be lower than the softening point of the material, thus preventing the material from melting and adhering prematurely. The heat insulation pad blocks the axial heat conduction from the second cylinder to the first cylinder, reducing the cooling load without affecting the process temperature of the main melting zone, thus balancing cooling effect and energy efficiency. The two work together to form a dual protection of "active cooling + heat conduction blocking", completely solving the problem of discharge port blockage.

[0008] As a further optimization of this utility model, the discharge port of the hopper is also fitted with an independent cooling sleeve. The cooling sleeve wraps around the circumference of the discharge port to achieve uniform cooling of the metal wall of the hopper. This not only pre-cools the material that is about to enter the feeding section, but also prevents the material from sticking due to the temperature rise of the hopper wall. The independent design allows for flexible control of the cooling intensity and forms a synergistic cooling with the heat insulation plate, further expanding the cooling protection range and improving the reliability of anti-blocking.

[0009] As a further optimization of this utility model, the cooling sleeve is a spiral coil water-cooled jacket or a jacketed water-cooled jacket. The spiral coil water-cooled jacket has a large heat exchange area and high cooling efficiency, and is suitable for high-temperature working conditions or materials that are easy to adhere to. The jacketed water-cooled jacket has a simple structure and is easy to maintain, and is suitable for conventional production scenarios. The two types can be flexibly selected according to the material characteristics and production needs, which enhances the versatility and adaptability of the device.

[0010] As a further optimized solution of this utility model, the heat insulation plate is pressed and fixed between the hopper and the first cylinder by a pad. The upper end of the pad is fixed to the discharge port of the hopper, and the lower end is fixed with bolts to ensure that the heat insulation plate is firmly installed and tightly fitted, so as to avoid displacement caused by vibration during cooling, and to ensure the heat exchange effect of the cooling channel and the interface. The pressing and fixing method does not damage the original equipment structure, is easy to disassemble and assemble, facilitates the maintenance or replacement of the heat insulation plate, and is compatible with the upgrading and transformation of existing equipment.

[0011] As a further optimization of this utility model, the heat insulation pad is a ceramic fiber composite metal pad. The ceramic fiber composite metal material has both extremely low thermal conductivity and good structural strength, and has excellent heat barrier effect. It can effectively block axial heat conduction. The metal layer enhances the pressure resistance and sealing performance of the pad, ensuring a stable connection between the first cylinder and the second cylinder, adapting to the vibration environment during the operation of the granulator, and extending its service life.

[0012] As a further optimization of this utility model, spiral cooling channels are provided inside the cylinder walls of both the first cylinder and the second cylinder. The spiral cooling channels make the cylinder walls cool evenly. The channels of the first cylinder help control the temperature of the feeding section and further prevent material adhesion. The channels of the second cylinder can adjust the temperature of the melting zone to ensure the plasticizing effect of the material. The overall design realizes comprehensive temperature control of the key areas of the granulator, taking into account both anti-clogging and product quality.

[0013] As a further optimization of this utility model, the surface roughness Ra value of the inner wall of the discharge port of the hopper is no greater than 0.4μm. The low surface roughness design can reduce the friction coefficient between the material and the inner wall of the discharge port, reduce the probability of material adhesion, and make it easy for a small amount of material to slide off the wall surface. At the same time, it facilitates cleaning operations, reduces the frequency of downtime for cleaning, improves production continuity, and works in conjunction with the cooling structure to improve the anti-clogging effect.

[0014] As a further optimization of this utility model, the device also includes a temperature sensor located near the discharge port. The temperature sensor is interlocked with the main control system and is used to automatically adjust the output of the external cooling system according to the detected temperature. The temperature sensor is a Pt resistance thermometer, which monitors the temperature in the discharge port area in real time. The main control system automatically adjusts the cooling intensity according to a preset threshold to achieve precise temperature control and avoid insufficient or excessive cooling. The interlocking design improves the automation level of the device and reduces manual intervention. At the same time, it issues an alarm or adjusts production parameters when the temperature is abnormal to ensure the safe and stable operation of the equipment.

[0015] As a further optimization of this utility model, the number of cooling channels inside the heat insulation plate is two or more. Multiple cooling channels increase the heat exchange area, improve cooling efficiency, ensure uniform temperature of the heat insulation plate as a whole, and avoid local hot spots that cause material adhesion. The channels can be designed in parallel or in series. Parallel channels provide more uniform cooling, while series channels provide higher cooling intensity, adapting to different cooling needs and enhancing the flexibility of the device.

[0016] As a further optimization of this utility model, the pipe connector is a quick-connect connector, which facilitates the rapid connection and disassembly of the cooling pipe, simplifies the installation and maintenance process of the device, and improves the operating efficiency; the connector has good sealing performance, avoids leakage of cooling medium, ensures stable operation of the cooling system, and is suitable for the continuous production conditions of the granulator.

[0017] The independent cooling and anti-clogging device for the feed inlet of a screw granulator proposed in this utility model has the following beneficial effects: (i) The composite cooling system consisting of the heat insulation plate cooling channel and the discharge port cooling sleeve can perform precise and efficient forced heat exchange in the key area most prone to adhesion, ensuring that the temperature in this area is always lower than the softening point of the material, thus eliminating bridging and sticking phenomena from the root. (ii) The high-performance heat insulation pad set between the first cylinder and the second cylinder effectively blocks the axial heat conduction from the high-temperature melting section to the feeding section, which greatly reduces the cooling load of the feeding section and allows the main melting zone to operate at the optimal process temperature without having to cool down the whole to accommodate the discharge port, thus significantly saving energy and ensuring the quality of the melt. (iii) The heat insulation plate, heat insulation pad and cooling sleeve of the device are all integrated on the standard interface of the existing granulator. The structure is compact and does not take up extra space. It is particularly suitable for upgrading and transforming existing production line equipment. It is highly versatile, easy to implement and has a high return on investment.

[0018] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0019] Figure 1 This is a front structural diagram of the present invention; Figure 2 This is a cross-sectional structural diagram of the present invention.

[0020] Figure descriptions: 1. Base; 2. First cylinder; 3. Second cylinder; 4. Screw spindle; 5. Feed hopper; 6. Pad; 7. Heat insulation plate; 8. Pipe joint; 9. Heat insulation pad; 10. Cooling sleeve. Detailed Implementation

[0021] The embodiments of this utility model are described in detail below. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar symbols denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0022] In this utility model, 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," "on top of," and "over" 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.

[0023] Please see Figure 1 and Figure 2The independent cooling and anti-clogging device for the feed port of a screw granulator proposed in this utility model includes a base 1, a first cylinder 2 installed on the side of the base 1, and a plurality of second cylinders 3 extending horizontally along its axis installed at the other end of the first cylinder 2. The motor output end of the base 1 is connected to a screw spindle 4 through a coupling. The other end of the screw spindle 4 passes through the first cylinder 2 and the plurality of second cylinders 3 in sequence. A feed hopper 5 is provided above the first cylinder 2. A pad 6 is installed at the feed port of the feed hopper 5. A heat insulation plate 7 is installed on the upper end face of the first cylinder 2. A feed inlet is opened at the upper end of the first cylinder 2 and at the corresponding position of the heat insulation plate 7, which is opposite to the feed port of the feed hopper 5. The pad 6 is pressed on the heat insulation plate 7 and fixed by bolts. The second cylinder 3 is equipped with a heating element. In actual use, the granular material in the hopper 5 enters the first cylinder 2 through the discharge port and the feed port. The screw spindle 4 is driven to rotate by the motor in the base 1, so that the granular material in the first cylinder 2 moves continuously into the second cylinder 3. The heating element in the second cylinder 3 heats the material, so that the granular material gradually melts and is extruded.

[0024] In order to reduce the heat conduction from the second cylinder 3 to the first cylinder 2, a heat insulation pad 9 is provided between the first cylinder 2 and the second cylinder 3. The heat insulation pad 9 is made of ceramic fiber composite metal with low thermal conductivity (≤0.2W / (m·K)) and an axial thickness of 15-25mm, which can effectively block heat conduction. Furthermore, both ends of the first cylinder 2 and the second cylinder 3 are provided with bosses, and two adjacent bosses are fixed together by multiple bolts evenly distributed around the circumference. The heat insulation pad 9 is provided with through holes that are compatible with the bolts, so that the heat insulation pad 9 can be stably installed between the first cylinder 2 and the second cylinder 3.

[0025] To further reduce the impact of shear heat and conduction heat on the hopper 5 and its discharge port, the heat insulation plate 7 is equipped with at least two circulating cooling channels, and each circulating cooling channel has pipe joints 8 installed at both ends. The pipe joints 8 are quick-connect joints and are connected to the circulating cooling equipment. The cooling medium can be water-cooled or compressed cold air, which can insulate and exchange heat between the first cylinder 2 and the pad 6, effectively blocking heat conduction and preventing the granular material from melting prematurely and causing blockage.

[0026] A cooling sleeve 10 is also installed outside the discharge port of the hopper 5. The cooling sleeve 10 is a spiral coil water-cooled sleeve or a jacketed water-cooled sleeve. The cooling medium is water or compressed cold air, which can cool the discharge port and prevent heat conduction from causing the particulate material to melt and adhere in advance in the discharge port, thereby avoiding blockage. In addition, the surface roughness Ra of the inner wall of the discharge port is Ra≤0.4μm, thereby reducing friction and facilitating actual cleaning operations.

[0027] It should be noted that the inner walls of the first cylinder 2 and the second cylinder 3 are also equipped with spiral cooling channels, which serve to cool and control the temperature.

[0028] In one embodiment, a Pt100 thermal resistor is arranged at each end of the axial direction of the discharge port of the hopper 5 and interlocked with the main control PLC. When the temperature exceeds the set threshold T1 (generally 5-10°C lower than the material softening point), the speed of the cooling pump of the circulating cooling equipment is automatically increased. If the temperature continues to rise to T2, an alarm is issued and the speed of the motor in the base 1 is reduced or the machine is stopped.

[0029] The working principle of this utility model is based on the concept of "three-level protection and precise temperature control". Through multiple layers of protection, it ensures that the material discharge area is in a safe low-temperature state, as detailed below. Level 1 protection: Active interface cooling This is the most direct and effective line of defense. The circulating cooling medium is pumped into the cooling channel integrated inside the heat insulation plate 7 through the pipe joint 8. The heat insulation plate 7 is located at the interface between the outlet of the hopper 5 and the inlet of the first cylinder 2. This is the key interface for material state change and heat transfer. The cooling channel continuously removes heat from two directions: one is the heat generated by the screw shearing of the first cylinder 2 below and the heat conducted through the cylinder, and the other is the ambient heat that may be conducted from the metal wall of the hopper 5. Through this active and forced heat exchange, the temperature of this key interface is strictly controlled below the softening point of the material, so that the surface of the material will not melt when it passes through this interface, and thus cannot adhere to the cylinder wall, fundamentally cutting off the physical conditions for the formation of "bridging" and "sticking". Second-level protection: Axial heat conduction blocking This is to reduce the load on the first level of protection and improve system energy efficiency. The high-performance heat insulation pad 9 set between the first cylinder 2 and the second cylinder 3 acts as a thermal barrier. With its extremely low thermal conductivity, it greatly blocks the axial heat conduction from the high-temperature melting section of the second cylinder to the lower-temperature feeding section of the first cylinder. This reduces the overall temperature level of the first cylinder 2, especially the lower area in contact with the heat insulation plate 7. This design allows the cooling system to focus on handling the screw shear heat and a small amount of conductive heat, without having to contend with the strong axial heat flow, thus resulting in higher cooling efficiency and lower energy consumption. Third level of protection: circumferential cooling at the discharge port. The cooling sleeve 10 is wrapped around the outside of the discharge port of the hopper 5 to uniformly cool the metal wall of the hopper 5 in a circumferential manner. On the one hand, it can pre-cool the material that is about to enter the critical interface and further reduce its temperature. On the other hand, it can prevent the temperature of the lower metal wall of the hopper from rising due to ambient temperature or heat dissipation of the equipment itself, thereby avoiding the material from adhering to the inner wall of the hopper too early before reaching the critical interface. It works in conjunction with the first-level protection to ensure that the entire material channel from the hopper to the first cylinder is in a safe low-temperature environment.

[0030] In summary, this invention constructs a comprehensive and three-dimensional local temperature control system through the synergistic effect of three measures: active cooling by the heat insulation plate, conduction blocking by the heat insulation pad, and pre-cooling assisted by the cooling sleeve. This system accurately maintains the temperature in the feed port area within a safe threshold without affecting the core melting process of the main unit, completely solving the long-standing problem of feed port blockage that has plagued the operation of granulators, and realizing efficient, stable, and continuous intelligent production.

[0031] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. An independent cooling and anti-clogging device for the feed inlet of a screw granulator, the granulator comprising a base (1), a first cylinder (2), a second cylinder (3), a screw mandrel (4), and a feed hopper (5), characterized in that: A heat insulation plate (7) is disposed between the discharge port of the hopper (5) and the first cylinder (2). The heat insulation plate (7) has an integrated cooling channel inside, and the cooling channel is connected to an external cooling system through a pipe joint (8). A heat insulation pad (9) is disposed between the connection interface of the first cylinder (2) and the second cylinder (3).

2. The independent cooling and anti-clogging device for the feed inlet of a screw granulator according to claim 1, characterized in that: The discharge port of the hopper (5) is also fitted with an independent cooling sleeve (10).

3. The independent cooling and anti-clogging device for the feed inlet of a screw granulator according to claim 2, characterized in that: The cooling sleeve (10) is a spiral coil water cooling sleeve or a jacketed water cooling sleeve.

4. The independent cooling and anti-clogging device for the feed inlet of a screw granulator according to claim 1, characterized in that: The heat insulation plate (7) is pressed and fixed between the hopper (5) and the first cylinder (2) by the pad (6).

5. The independent cooling and anti-clogging device for the feed inlet of a screw granulator according to claim 1, characterized in that: The heat insulation pad (9) is a ceramic fiber composite metal pad.

6. The independent cooling and anti-clogging device for the feed inlet of a screw granulator according to claim 1, characterized in that: Both the first cylinder (2) and the second cylinder (3) have spiral cooling channels inside their cylinder walls.

7. The independent cooling and anti-clogging device for the feed inlet of a screw granulator according to claim 1, characterized in that: The surface roughness Ra value of the inner wall of the discharge port of the hopper (5) is not greater than 0.4 μm.

8. The independent cooling and anti-clogging device for the feed inlet of a screw granulator according to claim 1, characterized in that: It also includes a temperature sensor located near the discharge port, which is interlocked with the main control system and used to automatically adjust the output of the external cooling system according to the detected temperature.

9. The independent cooling and anti-clogging device for the feed inlet of a screw granulator according to claim 1, characterized in that: The number of cooling channels inside the heat insulation plate (7) is two or more.

10. An independent cooling and anti-clogging device for the feed inlet of a screw granulator according to claim 1, characterized in that: The pipe connector (8) is a quick-connect type connector.

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