A PVC pipe production process

Abstract

A PVC pipe production process, the steps include batching, extrusion molding, vacuum shaping, water tank cooling, traction, cutting, packaging, the water tank cooling step is implemented in the pipe water cooling device; The pipe water cooling device includes an automatic control module, a water tank body, a tank cover matched with the water tank body, a first partition plate arranged in the water tank body, a perforation provided on the end of the water tank body and the first partition plate for the pipe to pass through, the first partition plate separates the cavity of the water tank body into a rapid cooling cavity and a uniform cooling cavity, and a dust blocking assembly is located on both sides of the cutting blade, and a cover is fixedly arranged on both sides of the cover, the immersion cooling and the spray cooling are combined first, and the whole cooling system can be adjusted according to the real-time temperature, so that the quality of the product is ensured.

Description

Technical Field

[0001] This application relates to the field of PVC pipe processing, and more specifically, to a PVC pipe production process. Background Technology

[0002] The current PVC pipe processing flow includes batching, extrusion molding, vacuum shaping, water tank cooling, traction, cutting, and packaging. In the processing of PVC pipes with the same material composition, in addition to the batching having a significant impact on the quality of the pipes, the water tank cooling step has a significant impact on the quality of the pipes.

[0003] After PVC pipes are extruded, they are at a high temperature, so they first need to be vacuum-shaped. Vacuuming is used to shape them. Under vacuum conditions, negative pressure can quickly cool and solidify the PVC pipes to maintain their shape, and can also reduce internal stress and improve product stability and quality. After vacuum shaping, the temperature of the PVC pipes is still higher than room temperature, so water cooling is needed to continuously reduce the temperature of the PVC pipes. Usually, PVC pipes are cooled by water tanks or spray systems, thereby accelerating the cooling and shaping of the pipes and ensuring product quality.

[0004] However, when cooling through a water tank, i.e., using an immersion cooling method, the PVC pipe generates buoyancy in the water, and the friction of the PVC pipe increases during the traction process, affecting the surface of the pipe. Moreover, immersion cooling does not completely submerge the PVC pipe; a portion remains exposed above the water surface. This portion is prone to deformation during cooling. When using a spray system for cooling, its cooling efficiency is worse than that of immersion cooling. Therefore, both conventional cooling methods currently have their own advantages and disadvantages.

[0005] Finally, the temperature of PVC pipes is not constant and fluctuates due to factors such as the temperature of the extruder head, the ambient temperature, and the traction speed during extrusion. Current cooling methods are all based on a set cooling temperature, and with the length of the water-cooled box fixed, the optimal cooling effect cannot be achieved.

[0006] Therefore, those skilled in the art need to improve the existing PVC pipe manufacturing process, especially its water tank cooling, in order to overcome the above-mentioned defects. Summary of the Invention

[0007] The main objective of this application is to provide a PVC pipe manufacturing process that combines immersion cooling and spray cooling, and allows for adjustment of the entire cooling system based on real-time temperature, thereby ensuring product quality.

[0008] To achieve the above objectives, in a first aspect, this application provides a PVC pipe manufacturing process, the steps of which include batching, extrusion molding, vacuum shaping, water tank cooling, traction, cutting, and packaging, wherein the water tank cooling step is performed in a pipe water cooling device.

[0009] The pipe water cooling device includes an automatic control module, a water tank body, a tank cover that cooperates with the water tank body, a first partition plate disposed in the water tank body, an opening at the end of the water tank body, and a through hole on the first partition plate for the pipe to pass through. The first partition plate divides the cavity of the water tank body into a rapid cooling cavity and a uniform cooling cavity.

[0010] The rapid cooling chamber is provided with a second partition that divides it into an inlet chamber and a return chamber. The second partition has an opening for the pipe to pass through. A hollow arc-shaped cooling plate is fixedly installed in the inlet chamber. The arc-shaped cooling plate is located above the pipe. The inner side of the arc-shaped cooling plate is densely covered with spray holes. The arc-shaped cooling plate is connected to a coolant inlet pipe that communicates with its cavity. A coolant return pipe is provided at the bottom of the return chamber. The coolant inlet pipe is connected to a coolant storage tank. A first suction pump is provided on the coolant inlet pipe.

[0011] The sidewall of the uniform cooling chamber is fixedly provided with several water spray components. Each water spray component includes a water passage chamber and several nozzles that are equidistantly distributed and connected to the water passage chamber. The water passage chamber is connected to an external water storage tank. The bottom of the water tank body is provided with a circulating water return pipe that is connected to the uniform cooling chamber. A second suction pump is provided on the circulating water return pipe.

[0012] It also includes a heat exchanger, the coolant return pipe and the circulating water return pipe are respectively connected to the heat exchanger, the coolant after heat exchange flows back to the coolant storage tank, and the water after heat exchange flows back to the water storage tank, and a condenser is installed in the water storage tank;

[0013] The automatic control module includes a controller, a temperature sensor for detecting the temperature of the pipe, a first flow regulating valve installed on the coolant inlet pipe, a frequency converter connected to the first suction pump, a second flow regulating valve installed on the coolant return pipe, and a first level sensor installed at a perforation in the first partition for detecting the coolant level. The controller is configured to control the first flow regulating valve and the frequency converter to adjust the coolant inlet flow rate based on the temperature value detected by the temperature sensor, and to adjust the second flow regulating valve to control the coolant level height in the return chamber based on the detection value of the first level sensor.

[0014] A further improvement is that a second liquid level sensor is also provided in the liquid inlet chamber. The second liquid level sensor is connected to the controller, which is also connected to an alarm. The controller controls the alarm based on the comparison result by comparing the detection value of the second liquid level sensor with a preset value.

[0015] A further improvement is that the lid has a first opening and a second opening, and a first regulating valve plate and a second regulating valve plate are respectively provided on the first opening and the second opening. The first regulating valve plate is located on the inner side of the lid, and the second regulating valve plate is located on the outer side of the lid. The first regulating valve plate and the second regulating valve plate are slidably disposed with the lid via a pull rod. The pull rod is respectively fitted with a spring to make the first regulating valve plate and the second regulating valve plate fit tightly against the lid.

[0016] A further improvement is that the batching step includes heating and mixing 65 parts CPVC, 6 parts impact-resistant reinforcing agent, 5 parts lubricant, 4 parts toughening agent, 8 parts stabilizer, and 8 parts titanium dioxide catalyst according to their weight fractions to form a material.

[0017] A further improvement is that the extrusion molding step includes drawing material from the material tray into the feed cylinder of the twin-screw extruder through vacuum suction, heating the main unit, starting the main unit for preheating, and after the temperature rises to the operating temperature, feeding the material in the feed cylinder into the die area through the suction pipe, opening the die for heating, and extruding the material that enters the die area through the suction pipe through the die after reaching the operating temperature.

[0018] A further improvement is that the cooled and solidified pipes are pulled into the cutting stage by the traction equipment. The standard length or the length required by the customer is set for traction cutting. The cut products are inspected. Qualified products are packaged in cardboard boxes according to different specifications, while unqualified products are crushed.

[0019] A further improvement is that the tank cover is rotatably connected to the water tank body.

[0020] A further improvement is that the cover is provided with several spray components corresponding to the uniform cooling chamber. Each spray component includes a spray chamber and several spray heads that are equidistantly distributed and connected to the spray chamber. The spray chamber is connected to an external water storage tank.

[0021] The present invention provides a PVC pipe manufacturing process, which has the following advantages compared with the prior art: First, the water-cooled box is divided into a rapid cooling chamber and a uniform cooling chamber. The pipe is first rapidly cooled in the rapid cooling chamber and then uniformly cooled in the uniform cooling chamber. Moreover, the rapid cooling chamber adopts an immersion cooling method, which has a good cooling effect, while the uniform cooling chamber adopts a spray cooling method.

[0022] In the immersion cooling chamber, the lower half of the pipe is immersed in the coolant, while the upper part is sprayed and cooled by the arc-shaped cooling plate. During immersion cooling, the pipe generates a certain buoyancy in the coolant, and the impact force of the coolant generated by the upper arc-shaped cooling plate on the pipe can offset this buoyancy, thereby reducing the resistance when the pipe is pulled and also enabling the pipe to be cooled comprehensively.

[0023] Finally, by real-time monitoring of the temperature of the pipes entering the water-cooling chamber, the flow rate of the coolant on the arc-shaped cooling plate is adjusted. When the temperature is high, the spray volume is increased to accelerate the cooling of the pipes, which is equivalent to accelerating the circulation speed of the coolant, thus further accelerating the cooling of the pipes. At the same time, increasing the spray volume causes the coolant level in the rapid cooling chamber to rise, preventing the coolant from overflowing into the uniform cooling chamber. The liquid level height is detected by the first liquid level sensor, and the liquid level of the coolant in the rapid cooling chamber is controlled by the second flow regulating valve.

[0024] In addition, the returning coolant exchanges heat with the returning cooling water in the uniform cooling chamber. After the coolant temperature drops, it is recycled. The cooling water after heat exchange returns to the water tank, is condensed by the condenser, and is recycled again. Attached Figure Description

[0025] The accompanying drawings, which form part of this application, are used to provide a further understanding of the application and to make other features, objects, and advantages of the application more apparent. The illustrative embodiments and descriptions of this application are used to explain the application and do not constitute an undue limitation of the application. In the drawings:

[0026] Figure 1 This is a schematic diagram of the water tank body. Figure 1 ;

[0027] Figure 2 This is a schematic diagram of the water tank body. Figure 2 .

[0028] The components are: 1. Water tank body; 2. Tank cover; 3. First partition; 4. Second partition; 5. Liquid inlet chamber; 6. Liquid return chamber; 7. Uniform cooling chamber; 8. Arc-shaped cooling plate; 9. Spray nozzle; 10. Spray head; 11. First regulating valve plate; 12. Second regulating valve plate. Detailed Implementation

[0029] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0030] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of this application described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0031] In this application, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing this application and its embodiments, and are not intended to limit the indicated device, element, or component to having a specific orientation, or to be constructed and operated in a specific orientation.

[0032] Furthermore, in addition to indicating location or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in some cases to indicate a certain dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0033] In addition, the term "multiple" should mean two or more.

[0034] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0035] A PVC pipe manufacturing process includes steps such as batching, extrusion molding, vacuum shaping, water tank cooling, traction, cutting, and packaging, wherein the water tank cooling step is performed in a pipe water cooling device.

[0036] like Figure 1-2As shown, the pipe water cooling device includes an automatic control module, a water tank body 1, a tank cover 2 that cooperates with the water tank body 1, a first partition 3 disposed inside the water tank body 1, a perforation opened at the end of the water tank body 1 and a perforation on the first partition 3 for the pipe to pass through, and the first partition 3 divides the cavity of the water tank body 1 into a rapid cooling cavity and a uniform cooling cavity 7.

[0037] The rapid cooling chamber is provided with a second partition 4 that divides it into an inlet chamber 5 and a return chamber 6. The second partition 4 has an opening for the pipe to pass through. A hollow arc-shaped cooling plate 8 is fixedly installed in the inlet chamber 5. The arc-shaped cooling plate 8 is located above the pipe. The inner side of the arc-shaped cooling plate 8 is densely covered with spray holes. The arc-shaped cooling plate 8 is connected to a coolant inlet pipe that communicates with its cavity. A coolant return pipe is provided at the bottom of the return chamber 6. The coolant inlet pipe is connected to a coolant storage tank. A first suction pump is provided on the coolant inlet pipe.

[0038] The side wall of the uniform cooling chamber 7 is fixedly provided with a number of water spray components. Each water spray component includes a water passage chamber and a number of nozzles 9 that are equidistantly distributed and connected to the water passage chamber. The water passage chamber is connected to an external water storage tank. The bottom of the water tank body 1 is provided with a circulating water return pipe that is connected to the uniform cooling chamber 7. A second suction pump is provided on the circulating water return pipe.

[0039] It also includes a heat exchanger, the coolant return pipe and the circulating water return pipe are respectively connected to the heat exchanger, the coolant after heat exchange flows back to the coolant storage tank, and the water after heat exchange flows back to the water storage tank, and a condenser is installed in the water storage tank;

[0040] The automatic control module includes a controller, a temperature sensor for detecting the temperature of the pipe, a first flow regulating valve installed on the coolant inlet pipe, a frequency converter connected to the first suction pump, a second flow regulating valve installed on the coolant return pipe, and a first liquid level sensor installed at the perforation of the first partition 3 for detecting the coolant level. The controller is configured to control the first flow regulating valve and the frequency converter to adjust the coolant inlet flow rate based on the temperature value detected by the temperature sensor, and to adjust the second flow regulating valve to control the coolant level height in the return chamber 6 based on the detection value of the first liquid level sensor.

[0041] The cooling process of the water tank is described in detail as follows: First, the temperature of the pipe output from the extruder is detected in real time by a temperature sensor. If the temperature exceeds the preset value, the controller controls the first flow regulating valve and the frequency converter to increase the power of the first suction pump, thereby increasing the inflow of coolant. This is equivalent to increasing the inflow while the outflow remains unchanged. This causes the liquid level in the rapid cooling chamber to rise, while the liquid level in the coolant storage tank to fall. The increased inflow also increases the impact force of the coolant sprayed from the arc-shaped cooling plate 8 on the upper part of the pipe. The rise in liquid level increases the volume of the pipe in the coolant, i.e., the buoyancy increases. The two factors cancel each other out, thus maintaining the pipe's traction and reducing the resistance of the traction wheel. Conversely, when the temperature is low, the power of the first suction pump is reduced and the second flow regulating valve is adjusted to reduce the coolant inflow, causing the liquid level in the inlet chamber 5 to drop. This reduces the buoyancy and the impact force, thus maintaining a balance. Moreover, the real-time adjustment of the power of the first suction pump based on the temperature also has a certain energy-saving effect.

[0042] Regarding the return chamber 6, to prevent coolant from mixing into the uniform cooling chamber 7 during immersion cooling and affecting the cooling water, the coolant returns through the opening between the inlet chamber 5 and the return chamber 6, creating a certain liquid level difference. It should be noted that to improve the cooling effect of the coolant circulation, the lowest point of the pipe should be as close as possible to the bottom of the chamber, but with a certain distance. This distance prevents the coolant from overflowing into the uniform cooling chamber 7 when the inlet volume is increased, ensuring that the amount of coolant remaining in the chamber is kept to a minimum. The liquid level difference between the inlet chamber 5 and the return chamber 6 can be achieved by increasing the inlet volume before processing. Since the opening size is fixed, the discharge volume is constant. When a certain liquid level is reached, controlling the inlet volume and the discharge volume at the opening to maintain a balance creates the liquid level difference. This also avoids the problem of coolant mixing into the spray cooling chamber when immersion cooling and spray cooling are combined.

[0043] To prevent the liquid level in the inlet chamber 5 from exceeding the warning line and overflowing the water tank body 1, a second liquid level sensor is also installed in the inlet chamber 5. The second liquid level sensor is connected to the controller, which is also connected to an alarm. The controller controls the alarm based on the comparison result by comparing the detection value of the second liquid level sensor with a preset value. When the staff hears the alarm, they can take emergency measures.

[0044] The box cover 2 has a first opening and a second opening, and a first regulating valve plate 11 and a second regulating valve plate 12 are respectively provided on the first opening and the second opening. The first regulating valve is located on the inner side of the box cover 2, and the second regulating valve plate 12 is located on the outer side of the box cover 2. The first regulating valve plate 11 and the second regulating valve plate 12 are slidably disposed with the box cover 2 by means of a pull rod. The pull rod is respectively fitted with a spring so that the first regulating valve plate 11 and the second regulating valve plate 12 are tightly attached to the box cover 2.

[0045] The first regulating valve plate 11 and the second regulating valve plate 12 are used mainly because after the pipe is rapidly cooled in the rapid cooling chamber, a large amount of high-temperature gas will accumulate in the chamber. If the high-temperature gas remains in the chamber, it will affect the cooling effect. Therefore, the first regulating valve plate 11 and the second regulating valve plate 12 are set up. Their function is that when the pressure of the high-temperature gas in the chamber is greater than the atmospheric pressure, the first regulating valve plate 11 opens outward under the action of internal pressure and discharges outward. When the external air pressure is higher than the internal air pressure, the second regulating valve plate 12 opens inward under the action of external pressure and cold air from the outside enters the chamber. This achieves the discharge of high-temperature gas from the chamber to the outside during operation. In the initial stage of stopping operation, especially in winter (when the external air pressure is higher than that in summer), cold air from the outside mixes into the chamber to cool down the high-temperature gas in the chamber.

[0046] In this embodiment, preferably, the batching step includes heating and mixing 65 parts CPVC, 6 parts impact-resistant reinforcing agent, 5 parts lubricant, 4 parts toughening agent, 8 parts stabilizer, and 8 parts titanium dioxide catalyst according to their weight fractions to form a material.

[0047] In this embodiment, preferably, the extrusion molding step includes drawing material from the material tray into the feeding barrel of the twin-screw extruder by vacuum suction, heating the main unit, starting the main unit for preheating, and after the temperature rises to the operating temperature, feeding the material in the feeding barrel into the mold area through the suction pipe, opening the mold for heating, and extruding the material that enters the mold area through the suction pipe through the mold tube after reaching the operating temperature.

[0048] In this embodiment, preferably, the cooled and solidified pipe enters the cutting stage under the traction of the traction equipment. The pipe is cut to a commonly used length or the length required by the customer. The cut products are inspected. Qualified products are packaged in cartons according to different specifications, while unqualified products are crushed.

[0049] To facilitate cleaning of the cooling water tank, the tank cover 2 is rotatably connected to the tank body 1.

[0050] In order to improve the cooling uniformity in the uniform cooling chamber 7, the cover 2 is provided with a number of spray components corresponding to the uniform cooling chamber 7. Each spray component includes a spray chamber and a number of spray heads 10 that are equidistantly distributed and connected to the spray chamber. The spray chamber is connected to an external water storage tank.

[0051] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A PVC pipe manufacturing process, comprising the steps of batching, extrusion molding, vacuum shaping, water tank cooling, traction, cutting, and packaging, characterized in that, The water tank cooling step is performed in the pipe water cooling device; The pipe water cooling device includes an automatic control module, a water tank body, a tank cover that cooperates with the water tank body, a first partition plate disposed in the water tank body, an opening at the end of the water tank body, and a through hole on the first partition plate for the pipe to pass through. The first partition plate divides the cavity of the water tank body into a rapid cooling cavity and a uniform cooling cavity. The rapid cooling chamber is provided with a second partition that divides it into an inlet chamber and a return chamber. The second partition has an opening for the pipe to pass through. A hollow arc-shaped cooling plate is fixedly installed in the inlet chamber. The arc-shaped cooling plate is located above the pipe. The inner side of the arc-shaped cooling plate is densely covered with spray holes. The arc-shaped cooling plate is connected to a coolant inlet pipe that communicates with its cavity. A coolant return pipe is provided at the bottom of the return chamber. The coolant inlet pipe is connected to a coolant storage tank. A first suction pump is provided on the coolant inlet pipe. The sidewall of the uniform cooling chamber is fixedly provided with several water spray components. Each water spray component includes a water passage chamber and several nozzles that are equidistantly distributed and connected to the water passage chamber. The water passage chamber is connected to an external water storage tank. The bottom of the water tank body is provided with a circulating water return pipe that is connected to the uniform cooling chamber. A second suction pump is provided on the circulating water return pipe. It also includes a heat exchanger, the coolant return pipe and the circulating water return pipe are respectively connected to the heat exchanger, the coolant after heat exchange flows back to the coolant storage tank, and the water after heat exchange flows back to the water storage tank, and a condenser is installed in the water storage tank; The automatic control module includes a controller, a temperature sensor for detecting the temperature of the pipe, a first flow regulating valve installed on the coolant inlet pipe, a frequency converter connected to the first suction pump, a second flow regulating valve installed on the coolant return pipe, and a first level sensor installed at the perforation of the first partition for detecting the coolant level. The controller is configured to control the first flow regulating valve and the frequency converter to adjust the coolant inlet flow rate based on the temperature value detected by the temperature sensor, and to adjust the second flow regulating valve to control the coolant level height in the return chamber based on the detection value of the first level sensor. The box cover has a first opening and a second opening, and a first regulating valve plate and a second regulating valve plate are respectively provided on the first opening and the second opening. The first regulating valve plate is located on the inner side of the box cover, and the second regulating valve plate is located on the outer side of the box cover. The first regulating valve plate and the second regulating valve plate are slidably connected to the box cover by a pull rod. The pull rod is respectively fitted with a spring to make the first regulating valve plate and the second regulating valve plate fit tightly against the box cover.

2. The PVC pipe manufacturing process as described in claim 1, characterized in that: A second liquid level sensor is also installed in the liquid inlet chamber. The second liquid level sensor is connected to the controller, which is also connected to an alarm. The controller controls the alarm based on the comparison result by comparing the detection value of the second liquid level sensor with a preset value.

3. The PVC pipe manufacturing process as described in claim 1, characterized in that: The batching process includes heating and mixing 65 parts CPVC, 6 parts impact-resistant reinforcing agent, 5 parts lubricant, 4 parts toughening agent, 8 parts stabilizer, and 8 parts titanium dioxide catalyst according to their respective weight fractions to form a material.

4. The PVC pipe manufacturing process as described in claim 1, characterized in that: The extrusion molding step includes drawing material from the material tray into the feed cylinder of the twin-screw extruder through vacuum suction, heating the main unit, starting the main unit for preheating, and after the temperature rises to the operating temperature, feeding the material in the feed cylinder into the die area through the suction pipe, opening the die for heating, and extruding the material that enters the die area through the suction pipe through the die after reaching the operating temperature.

5. The PVC pipe manufacturing process as described in claim 1, characterized in that: After cooling and solidification, the pipes are pulled into the cutting stage by the traction equipment. The standard length or the length required by the customer is set for traction cutting. The cut products are inspected. Qualified products are packaged in cardboard boxes according to different specifications, while unqualified products are crushed.

6. The PVC pipe manufacturing process as described in claim 1, characterized in that: The tank cover is rotatably connected to the water tank body.

7. The PVC pipe manufacturing process as described in claim 1, characterized in that: The cover is provided with several spray components corresponding to the uniform cooling chamber. Each spray component includes a spray chamber and several spray heads that are equidistantly distributed and connected to the spray chamber. The spray chamber is connected to an external water storage tank.

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