An extrusion barrel thermostatic control system and method

Abstract

The application discloses an extrusion barrel constant temperature control system and method, belongs to the technical field of film processing, and relates to a barrel, wherein a water-cooled heater for controlling the temperature of the barrel is arranged on the barrel, the water-cooled heater is arranged in an inner-outer double-layer mode, a layer of stainless steel water pipe is tightly wound on the outer layer, heating wires are arranged on the inner layer, the heating wires are connected with a temperature controller for heating the heating wires, and a perfusion module for pumping cooling water into the stainless steel water pipe and the water tank is arranged between the stainless steel water pipe and the water tank.

Description

Technical Field

[0001] This invention belongs to the field of thin film processing technology, and in particular relates to a constant temperature control system and method for an extrusion barrel. Background Technology

[0002] In film production lines, the front end of a single-screw extruder needs to be heated to maintain a temperature of 180°C when it is not running. When it is running, the screw itself generates heat, so the barrel needs to be cooled to maintain a temperature of 220°C. Therefore, the barrel needs to be heated when the machine is stopped and cooled when it is running to maintain a stable equipment temperature. Usually, the heating and cooling equipment are relatively opposing devices, so users need to frequently switch between the heating and cooling equipment during use. A system that facilitates heating or cooling of the barrel is proposed. Summary of the Invention

[0003] To address the shortcomings of existing technologies, this invention provides a constant temperature control system and method for extrusion barrels, which solves the aforementioned problems.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a constant temperature control system and method for an extrusion barrel, comprising a barrel, wherein a water-cooled heater for controlling its temperature is provided on the barrel, the water-cooled heater is configured with inner and outer double layers, the outer layer is tightly wound with a layer of stainless steel water pipe, the inner layer is provided with a heating wire, the heating wire is connected to a temperature controller via a solid-state relay, and an injection module for pumping cooling water into the stainless steel water pipe is provided between the stainless steel water pipe and the water tank.

[0005] A further technical solution: The material cylinder is equipped with a PT100 temperature sensor for collecting its temperature, and the PT100 temperature sensor is connected to a temperature controller.

[0006] Further technical solution: The infusion module includes a booster pump and a circulation component. The booster pump is connected to a water tank and is used to pump water from the water tank into a stainless steel water pipe. An electrically controlled EP valve is installed between the booster pump and the water-cooled heating coil. The electrically controlled EP valve is connected to the inlet of the stainless steel water pipe and is electrically connected to a PT100 temperature sensor so that when the barrel temperature is lower than the expected temperature, the PT100 temperature sensor sends a signal to close the electrically controlled EP valve. The circulation component is used to return the water remaining in the stainless steel water pipe to the water tank.

[0007] A further technical solution: A filter is installed between the booster pump and the water tank to filter out impurities in the tank. Water in the tank flows into the booster pump after being filtered by the filter.

[0008] Further technical solution: The circulation component includes a heat exchanger, which is disposed between a stainless steel water pipe and a water tank. A check valve is provided between the heat exchanger and the stainless steel water pipe to prevent convection between waters in different circuits. The check valve is located at the outlet of the stainless steel water pipe. The cavity of the heat exchanger is divided into two independent cavities by a metal pipe wall. One cavity is filled with circulating coolant, and the other cavity is connected to the outlet of the check valve, thereby cooling the high-temperature water input into it through the coolant inside.

[0009] A further technical solution: The water tank is equipped with a cleaning component to prevent the water inside from becoming turbid. The cleaning component includes an outlet and return water valve, which is located between the heat exchanger and the water tank. A drain valve is also provided on the drain outlet of the water tank.

[0010] Further technical solution: A water tank inlet control valve is provided at the water inlet of the water tank, and a high water level detection sensor is provided at the high water level on the inner wall of the water tank, and a low water level detection sensor is provided at the low water level on the inner wall of the water tank.

[0011] Beneficial effects This invention provides a constant temperature control system and method for extrusion barrels, which has the following advantages compared with the prior art: 1. The PT100 temperature sensor collects the barrel temperature in real time and transmits the temperature signal to the temperature controller. Assuming the expected temperature is set to T0, when the barrel temperature equals T0, the system is in a stable state. The water tank maintains a certain water level through the water tank inlet control valve. High-level and low-level sensors monitor the water level in real time. A filter is installed between the booster pump and the water tank to filter the water entering the booster pump. At this time, the electrically controlled EP valve is open, and the booster pump pumps the filtered water from the water tank into the stainless steel water pipe. The water flows in the stainless steel water pipe, cooling the outer layer of the water-cooled heater. A check valve at the outlet of the stainless steel water pipe prevents backflow. The high-temperature water flowing out of the stainless steel water pipe enters the heat exchanger, is cooled by the coolant in the heat exchanger, and then flows back to the water tank through the return valve. The heating wire maintains its current power under the control of the temperature controller to keep the barrel temperature stable. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the process framework of the present invention. Detailed Implementation

[0013] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0014] The specific implementation of the present invention will be described in detail below with reference to specific embodiments.

[0015] Please see Figure 1 According to one embodiment of the present invention, an extrusion barrel constant temperature control system and method are provided, including a barrel, on which a water-cooled heater for controlling its temperature is provided. The water-cooled heater is configured with inner and outer double layers. The outer layer is tightly wound with a layer of stainless steel water pipe, and the inner layer is provided with a heating wire. The heating wire is connected to a temperature controller through a solid-state relay. An injection module for pumping cooling water into the stainless steel water pipe is provided between the stainless steel water pipe and the water tank.

[0016] Specifically, the barrel is equipped with a PT100 temperature sensor for collecting its temperature, and the PT100 temperature sensor is connected to a temperature controller.

[0017] Specifically, the infusion module includes a booster pump and a circulation assembly. The booster pump is connected to a water tank and is used to pump water from the water tank into a stainless steel water pipe. An electrically controlled EP valve is installed between the booster pump and the water-cooled heating coil. The electrically controlled EP valve is connected to the inlet of the stainless steel water pipe and is electrically connected to a PT100 temperature sensor so that when the barrel temperature is lower than the expected temperature, the PT100 temperature sensor sends a signal to close the electrically controlled EP valve. The circulation component is used to return the water flowing out of the stainless steel water pipe to the water tank.

[0018] Specifically, a filter is installed between the booster pump and the water tank to filter out impurities in the tank. Water in the tank flows into the booster pump after being filtered by the filter.

[0019] Specifically, the circulation assembly includes a heat exchanger, which is disposed between a stainless steel water pipe and a water tank. A check valve is installed between the heat exchanger and the stainless steel water pipe to prevent convection between water from different circuits. The check valve is located at the outlet of the stainless steel water pipe. The cavity of the heat exchanger is divided into two independent cavities by a metal pipe wall. One cavity contains circulating coolant, and the other cavity is connected to the outlet of the check valve, thereby cooling the high-temperature water input into it through the coolant inside.

[0020] Specifically, the water tank is equipped with a cleaning component to prevent the water inside from becoming turbid. The cleaning component includes an outlet and return water valve, which is located between the heat exchanger and the water tank, and a drain valve is provided on the drain outlet of the water tank.

[0021] Specifically, a water tank inlet control valve is provided at the water inlet of the water tank, and a high water level detection sensor is provided at the high water level of the inner wall of the water tank, and a low water level detection sensor is provided at the low water level of the inner wall of the water tank; when the water in the water tank is at the low water level, the low water level detection sensor can be triggered, so that the inlet control valve is opened to start injecting water into the water tank. As the injection time increases, the liquid level in the water tank gradually increases until the water level reaches the high water level detection sensor, and at this time, the inlet control valve can be closed to stop injecting water into the water tank.

[0022] Specifically, a pressure gauge for detecting the pipeline pressure is provided on the pipeline between the electric control EP valve and the booster pump. When the pressure deviates from the expected value, the output value of the booster pump can be adjusted to increase or decrease the pressure in the pipeline. And a mechanical pressure switch is provided on the pipeline, and the other end of the mechanical pressure switch is connected between the heat exchanger and the outlet and return water valve; the pressure gauge continuously detects the pressure of the pipeline between the electric control EP valve and the booster pump. Assume that the expected pressure value is P0. When the detected pressure P > P0, it means that the pressure in the pipeline is too high; when P < P0, it means that the pressure in the pipeline is too low. When the pressure deviates from the expected value, the pipeline pressure is adjusted by adjusting the output value of the booster pump. If P > P0, the output power of the booster pump is reduced, and the amount of water pumped into the stainless steel water pipe is reduced, thereby reducing the pipeline pressure; if P < P0, the output power of the booster pump is increased, and the amount of water pumped into the stainless steel water pipe is increased to increase the pipeline pressure. At the same time, the mechanical pressure switch continuously monitors the pressure situation. When the abnormal pressure situation persists or reaches a certain threshold, an alarm signal can be issued or further protection measures can be taken.

[0023] Embodiment 1, normal constant temperature control state: The PT100 temperature sensor continuously collects the temperature of the barrel and transmits the temperature signal to the temperature controller. Assume that the expected temperature is set to T0. When the temperature of the barrel is equal to T0, the system is in a stable state. The water tank maintains a certain water level through the water tank inlet control valve. The high water level detection sensor and the low water level detection sensor continuously monitor the water level. The filter is installed between the booster pump and the water tank to filter the water entering the booster pump; at this time, the electric control EP valve is in the open state, and the booster pump pumps the filtered water in the water tank into the stainless steel water pipe. The water flows in the stainless steel water pipe to cool the outer layer of the water-cooled heater. The check valve at the outlet of the stainless steel water pipe prevents water from flowing back. The high-temperature water flowing out of the stainless steel water pipe enters the heat exchanger and is cooled by the coolant in the heat exchanger, and then flows back to the water tank through the outlet and return water valve. At this time, the temperature controller does not output a signal to make the heating wire energized, so the heating wire maintains the current power to keep the temperature of the barrel stable.

[0024] Embodiment 2, when the temperature of the barrel is lower than the expected temperature: The PT100 temperature sensor collects the barrel temperature T1, and T1 < T0 (expected temperature). The PT100 temperature sensor transmits the temperature signal to the temperature controller, and at the same time sends a signal to close the electronic control EP valve. At this time, the booster pump continues to work, but due to the closing of the electronic control EP valve, the water in the water tank cannot enter the stainless steel water pipe, and the cooling of the outer layer of the water-cooled heater stops. At the same time, the temperature controller outputs a signal to the solid-state relay to energize the heating wire, and the heating wire increases its power, causing the barrel temperature to rise. As the power of the heating wire increases, the barrel temperature gradually rises. When the PT100 temperature sensor detects that the barrel temperature has risen back to T0, it sends a signal to reopen the electronic control EP valve, and the booster pump pumps the water in the water tank to the stainless steel water pipe, restoring the cooling of the outer layer of the water-cooled heater, and the system enters a stable state again.

[0025] Embodiment 3. When the barrel temperature is higher than the expected temperature: The PT100 temperature sensor collects the barrel temperature T2, and T2 > T0. After receiving the signal from the PT100 temperature sensor, the temperature controller outputs a signal to stop energizing, and at this time the heating wire reduces its power. At the same time, since the electronic control EP valve is in the open state, the booster pump continuously pumps the water in the water tank into the stainless steel water pipe to strengthen the cooling of the outer layer of the water-cooled heater. After the water in the stainless steel water pipe absorbs heat, it enters the heat exchanger through the check valve, and after being cooled by the coolant, it flows back to the water tank. As the cooling is strengthened and the power of the heating wire is reduced, the barrel temperature gradually drops. When the PT100 temperature sensor detects that the barrel temperature has dropped to T0, the heating wire resumes its normal power, and the system maintains a stable constant temperature state.

[0026] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device.

[0027] The so-called fixed connection in this application means that after the parts or components are fixed, there is no relative movement between them. It is divided into two types: detachable connection and non-detachable connection.

[0028] (1) Detachable connection: Use screws, splines, wedge pins, etc. to fix the parts together. This connection method can be disassembled during maintenance and will not damage the parts. However, the specifications of the connecting parts used must be correct (such as the length of bolts, keys, and wedge pins), and tightened properly.

[0029] (2) Non-removable connections: These mainly refer to welding, riveting, and tenon joints. Since disassembly requires forging, sawing, or oxy-acetylene cutting for repair or replacement, these parts generally cannot be reused. Furthermore, during connection, [the following should be noted]: Pay attention to process quality, technical testing, and remedial measures (such as correction, polishing, etc.).

[0030] The sliding connection referred to in this application means that the component can slide along a linear trajectory, and the hinge referred to in this application means that the component can rotate along an axial constraint.

[0031] In some cases, the sliding connection and hinge referred to in this application may also be damped, enabling the component to maintain in the desired position.

[0032] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A constant temperature control system for an extrusion barrel, characterized in that, It includes a barrel, on which a water-cooled heater for controlling its temperature is provided. The water-cooled heater is arranged in an inner and outer double layer. A layer of stainless steel water pipe is closely wound around the outer layer, and heating wires are arranged in the inner layer. The heating wires are connected to a temperature controller through a solid state relay. An infusion module for pumping cooling water into it is arranged between the stainless steel water pipe and the water tank.

2. The constant temperature control system for the extrusion barrel according to claim 1, characterized in that, A PT100 temperature sensor for collecting its temperature is arranged on the barrel, and the PT100 temperature sensor is connected to the temperature controller.

3. The constant temperature control system for the extrusion barrel according to claim 2, characterized in that, The infusion module includes a booster pump and a circulation component. The booster pump is connected to the water tank and is used to pump the water in the water tank into the stainless steel water pipe. An electric control EP valve is arranged between the booster pump and the water-cooled heating coil. The electric control EP valve is connected to the water inlet of the stainless steel water pipe, and the electric control EP valve is electrically connected to the PT100 temperature sensor, so that when the temperature of the barrel is lower than the expected temperature, the electric control EP valve is closed by sending a signal through the PT100 temperature sensor; The circulation component is used to return the water flowing out of the stainless steel water pipe to the water tank.

4. The constant temperature control system for the extrusion barrel according to claim 2, characterized in that, A filter for filtering impurities in it is arranged between the booster pump and the water tank, and the water in the water tank flows into the booster pump after being filtered by the filter.

5. The constant temperature control system for the extrusion barrel according to claim 4, characterized in that, The circulation component includes a heat exchanger. The heat exchanger is arranged between the stainless steel water pipe and the water tank, and a check valve for preventing the water in different circuits from flowing convection is arranged between the heat exchanger and the stainless steel water pipe. The check valve is arranged on the water outlet of the stainless steel water pipe.

6. The constant temperature control system for the extrusion barrel according to claim 5, characterized in that, A cleaning component for preventing the water in it from being turbid is arranged in the water tank. The cleaning component includes an inlet and outlet water valve. The inlet and outlet water valve is arranged between the heat exchanger and the water tank, and a drain valve is arranged on the drain outlet of the water tank.

7. The constant temperature control system for the extrusion barrel according to claim 4, characterized in that, A water tank inlet control valve is arranged at the water inlet of the water tank, and a high water level detection sensor is arranged at the high water level of the inner wall of the water tank, and a low water level detection sensor is arranged at the low water level of the inner wall of the water tank.

8. A method for constant temperature control of an extrusion barrel, characterized in that, It includes the following steps: S1. The PT100 temperature sensor collects the temperature T1 of the barrel, and T1 < T0. The PT100 temperature sensor transmits the temperature signal to the temperature controller and sends a signal to close the electric control EP valve at the same time; S2. The water in the water tank cannot enter the stainless steel water pipe, and the cooling of the outer layer of the water-cooled heater is stopped; S3. The temperature controller increases the power of the heating wire to raise the temperature of the barrel. As the power of the heating wire increases, the temperature of the barrel gradually rises; S4. When the PT100 temperature sensor detects that the temperature of the barrel rises back to T0, it sends a signal to reopen the electric control EP valve. The booster pump pumps the water in the water tank into the stainless steel water pipe, and the cooling of the outer layer of the water-cooled heater is restored, and the system enters a stable state again.

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