Cooling system for an extruder and a pelletizing system

Abstract

The utility model relates to a kind of cooling system and granulating system for extruder, and extruder includes barrel, cooling system includes cooling water source, cooling pump, water inlet pipeline and backwater pipeline;Adjusting valve is provided on water inlet pipeline, it has adjustable opening for adjusting the water inlet amount into the barrel;Cooling system further includes manual switch for controlling the start-stop of cooling pump;Adjusting valve has initial minimum opening, and it is configured to be at initial minimum opening when cooling pump is deactivated and can gradually increase from initial minimum opening to predetermined opening when cooling pump restarts.The cooling system of the utility model embodiment is by dispensing with the automatic start-stop module of cooling pump and separately setting a manual switch for controlling the start-stop of cooling pump, and by setting adjusting valve with adjustable opening, effectively avoid a large amount of cooling water entering high-temperature barrel in a short time, solve the problem of barrel cracking due to improper cooling pump restart.

Description

Technical Field

[0001] This utility model relates to the field of granulation technology, specifically to a cooling system and a granulation system for an extruder. Background Technology

[0002] During the production operation of the extruder in the granulation system, the temperature control of the extruder barrel is crucial to product quality and equipment safety. The cooling pump, which supplies cooling water to the barrel, is a core component of the extruder cooling system, and its operating status is directly related to the stability of the cooling system's water supply, thus affecting the temperature balance of the extruder barrel.

[0003] To improve the automation level of extruder cooling systems, engineers designed and developed an automatic control module for continuous operation, thereby increasing production efficiency. However, in practical applications, the cooling pump often restarts accidentally. This automatic restart can lead to a large amount of cooling water being rapidly introduced into the high-temperature extruder barrel within a short period. Due to the significant temperature difference between the extruder barrel and the cooling water, the barrel experiences excessive internal stress due to rapid thermal expansion and contraction, resulting in cracking. Cracks in the extruder barrel not only directly cause production interruptions and significant economic losses, but also require substantial manpower and resources for repair or replacement, significantly increasing equipment maintenance costs. Furthermore, they can lead to safety hazards such as cooling water leaks, threatening operational safety on the production floor and the surrounding environment.

[0004] Therefore, there is a need to propose an improved cooling system for extruders to ensure stable operation of the extruders and reduce the risk of equipment failure and maintenance costs. Utility Model Content

[0005] The purpose of this utility model is to solve at least one of the above-mentioned problems and / or other problems existing in the prior art.

[0006] To achieve the above objectives, according to one aspect of the present invention, a cooling system for an extruder is provided. The extruder includes a barrel, and the cooling system includes a cooling water source, a cooling pump fluidly connected to the cooling water source, an inlet pipe for fluidly connecting the outlet end of the cooling pump to the barrel, and a return pipe for fluidly connecting the barrel to the inlet end of the cooling pump. A regulating valve is provided on the inlet pipe, the regulating valve having an adjustable opening for regulating the amount of water entering the barrel. The cooling system also includes a manual switch for controlling the start and stop of the cooling pump. The regulating valve has an initial minimum opening, and is configured to be at the initial minimum opening when the cooling pump is stopped and to gradually increase from the initial minimum opening to a predetermined opening when the cooling pump is restarted.

[0007] In one implementation, the cooling pump is configured to be enabled or disabled only via the manual switch.

[0008] In one embodiment, the extruder barrel includes multiple sections, and the water inlet pipeline includes multiple water inlet sections that are in fluid communication with the multiple sections respectively, with a regulating valve provided on each water inlet section.

[0009] In one implementation, the initial minimum opening degree of the control valves assigned to different sections is the same for each other.

[0010] In one implementation, the predetermined opening degrees of the control valves assigned to different sections may be the same or different from each other.

[0011] In one implementation, the regulating valve is maintained at the initial minimum opening or the predetermined opening when the cooling system is in continuous operation.

[0012] In one implementation, the initial minimum opening is 5% of the maximum opening of the regulating valve.

[0013] According to another aspect of the present invention, a granulation system is provided, the granulation system comprising an extruder and a cooling system as described above.

[0014] In one embodiment, the extruder barrel includes multiple different sections, and the regulating valves belonging to each different section have the same or different opening degrees when the cooling system is in continuous operation.

[0015] The cooling system according to this utility model eliminates the need for an automatic start / stop module for the cooling pump and instead provides a separate manual switch for controlling the start and stop of the cooling pump, thus preventing any accidental restart of the cooling pump. In addition, by setting up an adjustable valve with an adjustable opening and configuring it to gradually increase from the initial minimum opening to a predetermined opening when the cooling pump restarts, a large amount of cooling water is effectively prevented from entering the high-temperature cylinder in a short period of time, fundamentally solving the technical problem of cylinder cracking caused by improper restart of the cooling pump. Attached Figure Description

[0016] The features and advantages of this utility model will become clear from the following detailed description provided with reference to the accompanying drawings. It should be understood that the following drawings are merely schematic and not necessarily drawn to scale, and therefore should not be considered as limitations on this utility model, wherein:

[0017] Figure 1 A schematic diagram of the structure of the barrel of an extruder according to an embodiment of the present invention is shown;

[0018] Figure 2 A schematic diagram of the working circuit of a cooling system for an extruder according to an embodiment of the present invention is shown. Detailed Implementation

[0019] Embodiments of the present invention are described below with reference to the accompanying drawings. In the following description, numerous specific details are set forth to enable those skilled in the art to more fully understand and implement the present invention. However, it will be apparent to those skilled in the art that implementations of the present invention may not include some of these specific details. Furthermore, it should be understood that the present invention is not limited to the specific embodiments described. Rather, the present invention can be conceived to be implemented with any combination of the features and elements described below, regardless of whether they relate to different embodiments. Therefore, the following aspects, features, embodiments, and advantages are for illustrative purposes only and should not be construed as elements or limitations of the claims unless expressly set forth in the claims.

[0020] The terms "first" and "second" are used below to describe the elements of this application. These terms are used only to distinguish the individual elements and not to limit the nature, order, or number of these elements. The terms "comprising" and "having" are used to indicate an open-ended inclusion and mean that there may be additional elements / components besides those listed.

[0021] In the overall production process of a granulator, the extruder is the core equipment for transforming raw materials into semi-finished granules. An extruder typically includes a barrel for extruding materials. To prevent melt degradation due to excessive barrel temperature, a cooling system is installed in the granulation system to supply cooling water to the barrel, controlling its temperature and ensuring continuous, stable operation. This guarantees the continuity of the granulation process and the quality of the granulated product.

[0022] Figure 1 A schematic diagram of the extruder barrel according to an embodiment of the present invention is shown. Figure 2 A schematic diagram of the working circuit of a cooling system for an extruder according to an embodiment of the present invention is shown. The following will refer to the reference... Figure 1 and Figure 2 This invention provides a detailed description of the specific structure and operation of a cooling system for an extruder according to an embodiment of the present invention.

[0023] See especially Figure 2The cooling system for the extruder includes: a cooling water source 2, which serves as a supply source of cooling medium, continuously providing cooling medium to the cooling system; a cooling pump 3, whose inlet end is fluidly connected to the cooling water source 2, used to draw cooling water from the cooling water source 2 and provide power to circulate the cooling water within the cooling system; an inlet pipe 4 and a return pipe 5, wherein one end of the inlet pipe 4 is fluidly connected to the outlet end of the cooling pump 3, and the other end extends and connects to the barrel 1 of the extruder, used to guide the cooling water supplied by the cooling pump 3 into the barrel 1; one end of the return pipe 5 is fluidly connected to the barrel 1, and the other end is connected to the inlet end of the cooling pump 3. Thus, a closed-loop circulation path is formed where cooling water is output from the cooling pump 3, enters the barrel 1 through the inlet pipe 4, and then flows back to the cooling pump 3 through the return pipe 5.

[0024] A regulating valve 6 is installed on the water inlet pipe 4, specifically on the section of pipe located between the outlet of the cooling pump 3 and the water inlet of the cylinder 1. The regulating valve 6 has an adjustable opening to regulate the amount of water entering the cylinder. It should be understood that the regulating valve can employ a valve body structure with an adjustable opening known in the art. For example, the regulating valve may have an adjustable valve core structure inside, allowing precise control of the amount of cooling water entering the cylinder by changing the valve core opening.

[0025] Unlike existing cooling solutions for extruders, this embodiment eliminates the automatic control module for the cooling pump and instead provides a separate manual switch 7 for controlling the start and stop of the cooling pump. The operator can manually control the start and stop of the cooling pump 3 by pressing this manual switch 7. In particular, the cooling pump 3 is configured to be enabled or disabled only via the manual switch 7. This effectively avoids any accidental restarts of the cooling pump caused by automatic switching logic.

[0026] When the extruder is in a stopped state, especially after the temperature inside the extruder reaches a predetermined threshold, the operator can operate the manual switch 7 to turn off the cooling pump 3, at which point the cooling pump 3 will be de-energized and stop running; when the extruder needs to be restarted, the operator can operate the manual switch 7 to turn on the cooling pump 3, and the cooling pump will be energized and start running.

[0027] In this embodiment, the regulating valve 6 has an initial minimum opening. At this initial minimum opening, the valve 6 is designed to allow only a small amount of cooling water to slowly enter the barrel. To avoid problems such as barrel cracking caused by a large influx of cooling water into the barrel when the cooling pump is accidentally restarted, the regulating valve can be configured to be at the initial minimum opening when the cooling pump is stopped, and to gradually increase from the initial minimum opening to a predetermined opening, or remain at the initial minimum opening, when the cooling pump is restarted. This setting of the regulating valve is very advantageous in preventing barrel cracking. Because the actual temperature difference between the temperature inside the extruder and the cooling water at the cooling pump outlet is very large after the cooling pump has been stopped for a period of time, if a large amount of cooling water enters the barrel when the cooling pump is restarted, it will cause excessive internal stress in the barrel due to the rapid temperature difference, leading to cracking.

[0028] This risk can be effectively avoided by setting a regulating valve with an initial minimum opening when the cooling pump restarts. Due to the initial minimum opening of the regulating valve (e.g., 5% of the maximum opening), the small amount of cooling water entering the barrel slowly absorbs heat from the hot barrel after contacting it. This prevents a rapid drop in barrel temperature due to excessive temperature difference and gradually reduces the barrel temperature to a suitable production range. During this process, because the cooling water volume is strictly controlled, the barrel can achieve stable cooling, effectively preventing cracking caused by internal stress due to thermal shock. As the barrel temperature gradually decreases and stabilizes, based on the extruder's production needs and real-time barrel temperature monitoring data, the regulating valve can be configured to gradually increase from the initial minimum opening (e.g., 5% of the maximum opening) to a predetermined opening (e.g., 20% of the maximum opening or other suitable opening), correspondingly increasing the amount of cooling water entering the barrel until the barrel temperature stabilizes within the target range required by the production process. At this point, the cooling system enters normal continuous operation, providing temperature assurance for stable extruder production.

[0029] See still Figure 1 and Figure 2 The extruder barrel 1 may include multiple sections 11, each with a slightly different temperature, thus requiring different amounts of cooling water. Therefore, the water inlet pipe 4 may include multiple water inlet sections 41 respectively in fluid communication with the multiple sections 11 of the barrel 1, and each water inlet section 41 is equipped with a regulating valve 6 (see...). Figure 2When the cooling pump 3 restarts, the regulating valves 6 assigned to different sections 11 are all configured to initially be at their minimum opening and gradually increase from the initial minimum opening. The initial minimum opening of each of these regulating valves can be the same, for example, all set to 5% of the maximum opening of the regulating valve. Of course, other parameter settings are also feasible according to actual working requirements. When the cooling system enters normal continuous operation (i.e., the cylinder is filled with cooling water and the cooling water is in a circulating state), the regulating valves 6 assigned to different sections 11 can gradually increase from their initial minimum opening to a predetermined opening. The predetermined opening of each regulating valve 6 can be the same or different. Of course, the regulating valves in certain specific sections can also remain at their initial minimum opening after the cooling system enters normal continuous operation, depending on actual needs.

[0030] The cooling system of this embodiment can be applied to a granulation system. For example, a granulation system includes an extruder and a cooling system for the extruder.

[0031] The cooling system according to this utility model eliminates the need for an automatic start / stop module for the cooling pump and instead provides a separate manual switch to control the start and stop of the cooling pump, thus preventing any accidental restart of the cooling pump. Furthermore, by incorporating an adjustable valve that gradually increases its opening from the initial minimum to a predetermined level or remains at the initial minimum when the cooling pump restarts, a large amount of cooling water is effectively prevented from entering the high-temperature cylinder in a short period. This fundamentally solves the technical problem of cylinder cracking caused by improper cooling pump restarts, while ensuring a stable and suitable cooling effect for the extruder during production, guaranteeing equipment safety and production continuity.

[0032] Various modifications and variations can be made to the embodiments disclosed above without departing from the scope or spirit of this invention. Other embodiments of this invention will be apparent to those skilled in the art based on the practice of this invention disclosed in this specification. This specification and the examples disclosed herein should be considered illustrative only, and the true scope of this invention is defined by the appended claims and their equivalents.

Claims

1. A cooling system for an extruder, the extruder comprising a barrel (1), characterized in that, The cooling system includes a cooling water source (2), a cooling pump (3) fluidly connected to the cooling water source, an inlet pipe (4) for fluidly connecting the outlet end of the cooling pump to the cylinder, and a return pipe (5) for fluidly connecting the cylinder to the inlet end of the cooling pump; wherein, a regulating valve (6) is provided on the inlet pipe, the regulating valve having an adjustable opening degree for regulating the amount of water entering the cylinder (1); the cooling system also includes a manual switch (7) for controlling the start and stop of the cooling pump (3); wherein, the regulating valve has an initial minimum opening degree, and is configured to be at the initial minimum opening degree when the cooling pump is stopped and to gradually increase from the initial minimum opening degree to a predetermined opening degree when the cooling pump is restarted.

2. The cooling system according to claim 1, characterized in that, The cooling pump (3) is configured to be enabled or disabled only via the manual switch (7).

3. The cooling system according to claim 2, characterized in that, The extruder barrel (1) includes multiple sections (11), and the water inlet pipe (4) includes multiple water inlet sections (41) that are in fluid communication with the multiple sections (11), and each water inlet section is provided with a regulating valve (6).

4. The cooling system according to claim 3, characterized in that, The initial minimum opening degree of the regulating valves (6) belonging to different sections is the same for each other.

5. The cooling system according to claim 4, characterized in that, The predetermined opening degrees of the control valves (6) belonging to different sections may be the same or different from each other.

6. The cooling system according to any one of claims 3 to 5, characterized in that, The regulating valve (6) is maintained at the initial minimum opening or the predetermined opening when the cooling system is in continuous operation.

7. The cooling system according to any one of claims 1 to 5, characterized in that, The initial minimum opening is 5% of the maximum opening of the regulating valve (6).

8. A granulation system, characterized in that, The granulation system includes an extruder and a cooling system according to any one of claims 1 to 7.

9. The granulation system according to claim 8, characterized in that, The extruder barrel comprises multiple different sections (11), and the regulating valves (6) belonging to each different section have the same or different opening degrees when the cooling system is in continuous operation.

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