Twin-screw extrusion molding machine for injection pipes and injection pipe manufacturing process

Abstract

This invention relates to the field of twin-screw extrusion equipment technology, specifically to a twin-screw extrusion molding machine for injection-molded pipes and the injection-molded pipe production process. It includes a base, with a drive box mounted on top of the base. This device, through the arrangement of a first processing chamber, a second processing chamber, a gas delivery pipe, and a hollow disc, allows gas to first contact the reaction solution to separate hydrogen chloride, and then contact activated carbon to separate vinyl chloride monomer and dioxins. This avoids interference from uniform filtration that could affect removal efficiency. Simultaneously, a servo motor enables the hollow disc and activated carbon to rotate circumferentially. The rotation of the hollow disc allows gas to contact the reaction solution at different locations through vents, and the activated carbon also rotates circumferentially to contact gas at different locations. The combination of an annular plate and vents allows gas to be diverted and evenly diffused, ensuring sufficient contact between the gas and the reaction solution and activated carbon, avoiding localized contact filtration that could affect the filtration effect.

Description

Technical Field

[0001] This invention relates to the field of twin-screw extrusion equipment technology, specifically to a twin-screw extrusion molding machine for injection-molded pipes and the production process for injection-molded pipes. Background Technology

[0002] Currently, most plastics are produced on extruders, which can be divided into single-screw and twin-screw extruders. Twin-screw extruders are developed based on single-screw extruders. They typically use two closely meshed screws that rotate in opposite directions to push, heat, and extrude the raw material into shape.

[0003] Existing twin-screw extruders use two screws (in the same direction or opposite directions) rotating inside the barrel to transport material from the hopper to the die. Simultaneously, as the screws rotate, the material is compressed, evenly dispersed through shearing and mixing by structures such as kneading blocks, and volatiles are removed. Finally, the material is extruded through the die. However, when plastic granules are heated and melted, they easily produce toxic gases such as hydrogen chloride (HCl), vinyl chloride monomer (VCM), and dioxins (PCDD / Fs). If these gases are not promptly adsorbed and filtered, they not only pose a serious threat to the health of operators but may also pollute the surrounding environment. There are also examples such as those published in CN208290429U. An automatic feeding device for a twin-screw extruder used in FEP granulation is disclosed in a utility model patent. It filters toxic gases through an adsorption pad. However, hydrogen chloride (HCl) is a polar molecule, while vinyl chloride monomer (VCM) and dioxins (PCDD / Fs) are non-polar organic compounds. Unmodified activated carbon has a very weak adsorption capacity for hydrogen chloride, while alkali-modified activated carbon will reduce its adsorption capacity for vinyl chloride monomer and dioxins, affecting the removal efficiency. In addition, the gas only flows in a local area of ​​the adsorption pad and is difficult to contact other parts of the adsorption pad, which can easily affect the purification efficiency and is inconvenient to use. Summary of the Invention

[0004] Therefore, it is necessary to provide a twin-screw extrusion molding machine for injection-molded pipes and an injection-molded pipe production process to address the existing technical problems.

[0005] To solve the problems of the prior art, the technical solution adopted by the present invention is as follows: a twin-screw extrusion molding machine for injection-molded pipes, including a base, a drive box installed on the top of the base, a screw rod rotatably installed on the side of the drive box through a gear set, an extrusion cylinder installed on the side of the drive box, a feed hopper and an extruder head respectively installed on the top and side of the extrusion cylinder, a heater fixed on the extrusion cylinder, and a gas treatment mechanism provided on the base;

[0006] The gas processing mechanism includes a processing box installed on the top of the base. The processing box has a first processing chamber and a second processing chamber connected from bottom to top. The first processing chamber and the second processing chamber are respectively provided with a hollow disc and two sector-shaped shells. Activated carbon is fixed on both of the two sector-shaped shells. An annular plate is installed in the second processing chamber. Multiple air vents are opened on the hollow disc and the annular plate. The base is provided with a drive air intake assembly that makes the hollow disc and the two sector-shaped shells rotate.

[0007] Furthermore, the drive intake assembly includes a mounting hole on the top of the hollow disc, on which an air supply pipe is installed. The two sector-shaped housings are fixedly connected to the air supply pipe via a fixing unit. The top of the air supply pipe extends outside the processing chamber and is fitted with a rotary joint. An exhaust port is provided at the bottom of the processing chamber. A first fan and a second fan are installed on the top of the processing chamber. An exhaust port and an exhaust port are provided on the top of the extrusion cylinder. An intake pipe and a first air pipe are respectively installed at the inlet and outlet ends of the first fan. The other ends of the intake pipe and the first air pipe are respectively connected to the exhaust port and the exhaust port. The rotary joint is connected, and the inlet and outlet ends of the second fan are respectively equipped with a second air pipe and an air outlet pipe. The second air pipe and the air outlet pipe are respectively connected to the exhaust port and the air inlet. Filter screens are installed in both the air outlet and the air inlet. A drive hole is opened at the bottom of the treatment box. A sleeve is rotatably installed on the drive hole. Two L-shaped plates are installed on the outside of the sleeve. Cutting blades are installed on the top of the two L-shaped plates. A movable rod is rotatably installed inside the sleeve. The hollow disc is installed on the top of the movable rod. A drive unit is provided on the base to make the movable rod and the sleeve rotate.

[0008] Furthermore, the drive unit includes a servo motor mounted on the side of the base. The top of the base has a mounting groove, and a rotating shaft is rotatably mounted in the mounting groove. One end of the rotating shaft is connected to the output shaft of the servo motor. A reciprocating threaded sleeve is fitted on the rotating shaft, and a movable seat is threaded onto the reciprocating threaded sleeve. A first rack and a second rack are mounted on the side of the movable seat. The bottom end of the movable rod extends outside the sleeve and is equipped with a first gear. The first gear meshes with the first rack. A second gear is mounted on the bottom end of the sleeve. The first gear and the second gear mesh with the first rack and the second rack, respectively. A degassing element adapted to the extrusion cylinder is provided on the base, and the degassing element is installed in conjunction with the rotating shaft.

[0009] Furthermore, a guide rod is installed in the mounting groove, and the movable seat is slidably connected to the guide rod.

[0010] Furthermore, the number of teeth on the first gear is greater than the number of teeth on the second gear.

[0011] Furthermore, the degassing element includes a turntable installed at one end of the rotating shaft, an eccentric shaft eccentrically mounted on the side of the turntable, a connecting rod rotatably sleeved on the eccentric shaft, a telescopic rod installed on the top of the base, a lifting block installed at the end of the telescopic rod, the other end of the connecting rod rotatably mounted on the bottom of the lifting block, a lifting plate installed on the side of the lifting block, multiple insert rods installed at the bottom of the lifting plate, and multiple insertion holes opened on the top of the extrusion cylinder, with fixing tubes adapted to the insert rods installed on each of the multiple insertion holes.

[0012] Furthermore, the fixing unit includes a sector-shaped block installed on the outer wall of the gas pipeline. The sector-shaped block has two movable cavities, and a sliding block is slidably installed in each of the two movable cavities. A moving rod and a locking block are respectively installed on the two sides of the two sliding blocks that are far apart from each other. The other end of each of the two moving rods extends out of the sector-shaped block and is installed with a pull plate. A limiting plate is installed at the bottom of each of the two sector-shaped housings. Two limiting grooves communicating with the movable cavities are opened at the top of the sector-shaped block. A slot is opened on the side of each of the two limiting plates. A spring is installed on the side of each of the two sliding blocks. The other end of each of the two springs is respectively installed on the inner side wall of the two movable cavities.

[0013] Furthermore, a partition plate is installed on the inner side wall of the first processing chamber, and a flow hole is opened in the middle of the partition plate, and a mesh demister is installed in the flow hole.

[0014] Furthermore, a sealing door is hinged to the side of the processing box, and a drain pipe connected to the first processing chamber is fixed to the bottom of the processing box, with a valve fixed to the drain pipe.

[0015] An injection molding tube production process using the above-mentioned twin-screw extrusion molding machine includes the following steps:

[0016] S1: Before use, pour the raw materials and reaction solution into the feed hopper and processing tank respectively. After the raw materials enter the feed hopper, they will enter the extrusion cylinder under the action of gravity. Then, the screw column is rotated by the drive box, which pushes the raw materials forward. During this process, the heater on the extrusion cylinder heats the raw materials in a gradient. Finally, the raw materials are evenly extruded through the forming flow channel of the extruder head, thus forming the extrusion.

[0017] S2: The gas in the extrusion cylinder is sent into the hollow disk and discharged from multiple vent holes on the hollow disk and comes into contact with the reaction solution. At this time, the reaction solution reacts with hydrogen chloride. Then the gas that has been dehydrated continues to move and comes into contact with activated carbon. The activated carbon adsorbs and filters vinyl chloride monomer and dioxin in the gas. The adsorbed gas is sent back into the extrusion cylinder.

[0018] S4: The hollow disk rotates, causing the gas to come into contact with the reaction solution at different positions. The rising gas is first blocked by the annular plate, and then dispersed upward through the vent holes, so that the gas diffuses evenly.

[0019] The beneficial effects of this invention compared to the prior art are:

[0020] Firstly, this device, by setting up a first processing chamber, a second processing chamber, a gas supply pipe, and a hollow disc, allows the gas to first contact the reaction solution to separate hydrogen chloride, and then contact the activated carbon to separate vinyl chloride monomer and dioxins. This avoids interference from uniform filtration that could affect removal efficiency. At the same time, a servo motor enables the hollow disc to rotate and the activated carbon to move in a circular motion. The rotation of the hollow disc allows the gas to contact the reaction solution at different locations through the vent holes, and the circular motion of the activated carbon also allows it to contact the gas at different locations. The combination of an annular plate and vent holes allows the gas to be diverted and diffused evenly, thus ensuring that the gas fully contacts the reaction solution and activated carbon, avoiding localized contact filtration that could affect the filtration effect.

[0021] Secondly, this device, by incorporating a servo motor, a second rack, a second gear, a sleeve, and an L-shaped plate, enables the cutting blade to rotate in a circular motion. This circular motion cuts the bubbles, refining their size, increasing the gas-liquid contact area, effectively improving reaction efficiency, and enhancing separation. Furthermore, the diameter ratio of the first and second gears ensures that the cutting blade's rotation speed exceeds that of the hollow disc, preventing the cutting blade from rotating too slowly or synchronously with the hollow disc, which would negatively impact the cutting effect. The inclusion of a separator plate 46, flow holes, a mesh demister, and heat-conducting plates effectively removes moisture from the gas, preventing damage to the activated carbon.

[0022] Thirdly, this device, by setting up a turntable, eccentric shaft, connecting rod, telescopic rod, lifting block and lifting plate, can make the insertion rod move up and down while the servo motor outputs. The up and down movement of the insertion rod will continuously insert the molten raw material in the extrusion cylinder under the action of the fixed tube 15, thereby causing the bubbles wrapped in the melt to burst. Then, the shear effect of the melt flow will be used to make the gas escape, thus avoiding the impact of bubble inclusion on product quality. Attached Figure Description

[0023] Figure 1 This is a three-dimensional structural diagram from a first-view perspective in the embodiment;

[0024] Figure 2 This is a three-dimensional structural diagram from the second perspective in the embodiment;

[0025] Figure 3 yes Figure 2 Enlarged view of the structure at point A in the middle;

[0026] Figure 4 This is a three-dimensional structural schematic diagram of a partial cross-section of the extrusion cylinder and processing box in the embodiment;

[0027] Figure 5 yes Figure 4 Enlarged view of the structure at point B in the middle;

[0028] Figure 6 This is a three-dimensional structural diagram of a partially cut-out portion of the base and processing box in the embodiment;

[0029] Figure 7 This is a three-dimensional structural diagram of a partial section of the processing box in the embodiment;

[0030] Figure 8 yes Figure 7 Enlarged view of the structure at point C;

[0031] Figure 9 This is an enlarged structural schematic diagram of a partial cross-section of the semicircular block and the fan-shaped shell in the embodiment.

[0032] The following are the components labeled in the diagram: 1. Base; 2. Extrusion cylinder; 3. Drive box; 4. Servo motor; 5. Processing box; 6. Sealing door; 7. Rotating shaft; 8. Turntable; 9. Eccentric shaft; 10. Connecting rod; 11. Telescopic rod; 12. Lifting block; 13. Lifting plate; 14. Insert rod; 15. Fixed pipe; 16. First processing chamber; 17. Second processing chamber; 18. Movable rod; 19. Hollow disc; 20. Gas supply pipe; 21. Rotary joint; 22. First fan; 23. Second fan; 24. Inlet pipe; 25. Outlet pipe. ; 26. Air outlet; 27. Air inlet; 28. Annular plate; 29. ​​Fan-shaped block; 30. Fan-shaped shell; 31. Activated carbon; 32. Reciprocating threaded sleeve; 33. Moving seat; 34. First rack; 35. First gear; 36. Second rack; 37. Second gear; 38. Sleeve; 39. L-shaped plate; 40. Cutting blade; 41. Moving rod; 42. Sliding block; 43. Locking block; 44. Limiting plate; 45. Spring; 46. Divider plate; 47. Mesh demister; 48. Heat-conducting plate; 49. Screw column. Detailed Implementation

[0033] To further understand the features, technical means, and specific objectives and functions achieved by the present invention, the present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments.

[0034] Figures 1-9 This is the preferred embodiment of the present invention, which is described below in conjunction with the accompanying drawings. Figures 1-9 The present invention will be further described below.

[0035] See attached document Figures 1-9 The invention relates to a twin-screw extrusion molding machine for injection-molded pipes and its production process. The machine includes a base 1, an extrusion cylinder 2 mounted on the upper side of the base 1, and two screw columns 49 arranged side-by-side within the extrusion cylinder 2, forming a twin-screw extrusion structure. A drive box 3 is mounted on the top of the base 1, and both screw columns 49 are connected to the drive box 3, exhibiting the same structure as the extrusion screw in a twin-screw extrusion molding machine disclosed in CN211994133U. The drive box 3 includes an extrusion motor and a reducer, both mounted on the base 1. The output shaft of the extrusion motor is connected to the input shaft of the reducer, and the output shaft of the reducer is connected to either screw column 49 via a coupling. Both screw columns 49 are equipped with meshing transmission gears. A feed hopper is located on the upper side of the feed end of the extrusion cylinder 2, and an extruder head is installed at the discharge end of the extrusion cylinder 2. A heater is fixed on the extrusion cylinder 2; specifically, the heater is existing technology and can be an electric heating coil. A gas handling mechanism is located on the base 1.

[0036] The gas processing mechanism includes a processing box 5 installed on the top of the base 1. The processing box 5 is a cuboid box located on one side of the middle of the extrusion cylinder 2. The processing box 5 has a first processing chamber 16 and a second processing chamber 17 arranged sequentially from bottom to top. The first processing chamber 16 is provided with a hollow disc 19. The second processing chamber 17 is provided with a circular shell composed of two sector shells 30. Both sector shells 30 are filled with activated carbon 31. An annular plate 28 is installed in the second processing chamber 17. The annular plate 28 is located below the sector shells 30. Multiple air vents are provided on both the hollow disc 19 and the annular plate 28. The base 1 is provided with a drive air intake assembly that allows the hollow disc 19 and the two sector shells 30 to rotate.

[0037] With the above structure, before use, the raw materials and reaction solution are poured into the feed hopper and processing tank 5 respectively. The raw materials enter the extrusion cylinder 2 through the feed hopper. The drive box 3 drives the screw column 49 to rotate, causing the raw materials to move along the extrusion cylinder 2. During this process, the heater outside the extrusion cylinder 2 heats the raw materials, causing them to gradually soften and melt. The molten raw materials continue to move along the extrusion cylinder 2 under the shearing and conveying action of the screw column 49, and are finally uniformly extruded through the forming channel of the extruder head, thus forming the extrusion. At the same time, during the processing, the gas in the extrusion cylinder 2 is sent into the hollow disk 19 by the drive air intake component and discharged from multiple vents of the hollow disk 19. After contacting the reaction solution, it reacts with the chlorine. Hydrogen chloride is absorbed, and the gas continues to move and react with activated carbon 31. Activated carbon 31 adsorbs and filters vinyl chloride monomer and dioxins in the gas. The filtered gas is then sent into the extrusion cylinder 2 through the driving air intake component, where hydrogen chloride, vinyl chloride monomer, and dioxins are filtered separately. The filtration efficiency is high. At the same time, the driving air intake component causes the hollow disk 19 and the two fan-shaped shells 30 to rotate, so that the gas comes into contact with the reaction solution and activated carbon 31 at different positions. During the gas rise, it is blocked by the annular plate 28, which disperses the gas upward through multiple vent holes on the annular plate 28, thereby making the gas diffuse evenly and ensuring that the gas comes into full contact with the reaction solution and activated carbon 31.

[0038] like Figures 2-6As shown, the drive intake assembly includes a mounting hole on the hollow disc 19, on which an air supply pipe 20 is installed. The upper end of the air supply pipe 20 extends out of the processing box 5, and the lower end extends into the mounting hole. An exhaust port is provided at the bottom of the processing box 5. Two fan-shaped housings 30 are fixedly connected to the air supply pipe 20 by a fixing unit. A rotary joint 21 is installed on the top of the air supply pipe 20. The rotary joint 21 is located outside the processing box 5. A first fan 22 and a second fan 23 are installed on the upper side of the processing box 5. An air outlet 26 and an air inlet 27 are provided on the top of the extrusion cylinder 2. An air inlet pipe 24 and a first air pipe are respectively installed at the inlet and outlet ends of the first fan 22. The other ends of the air inlet pipe 24 and the first air pipe are respectively connected to the inner wall of the air outlet 26. The second fan 23 is connected to the rotary joint 21. A second air pipe and an air outlet pipe 25 are installed at the inlet and outlet ends of the second fan 23, respectively. The second air pipe and the air outlet pipe 25 are connected to the exhaust port and the air inlet port 27, respectively. Filter screens are installed inside both the air outlet port 26 and the air inlet port 27. A drive hole is provided at the bottom of the treatment box 5. A sleeve 38 is rotatably installed inside the drive hole. Two L-shaped plates 39 are symmetrically installed on both sides of the sleeve 38. A cutting blade 40 is installed on the top of each of the two L-shaped plates 39. The cutting blade 40 is arranged radially along the hollow disc 19. A movable rod 18 is rotatably installed inside the sleeve 38. The hollow disc 19 is coaxial and fixedly installed on the top of the movable rod 18. A drive unit is provided on the base 1 to rotate the movable rod 18 and the sleeve 38. In this embodiment, the movable rod 18 and the sleeve 38 are sealed together, which can be achieved by using a sealing ring or a mechanical seal.

[0039] In this scheme, the gas flowing out of the extrusion cylinder 2 is adsorbed and filtered before being discharged back into the extrusion cylinder 2. Through the setting of the movable rod 18, sleeve 38, L-shaped plate 39 and cutting blade 40, the hollow disk 19 rotates and drives the cutting blade 40 to move, thereby cutting the bubble.

[0040] Specifically, the toxic gas in the extrusion cylinder 2 can be drawn and transported through the gas supply pipe 20, rotary joint 21, first fan 22, inlet pipe 24, first gas pipe and outlet 26, so that the gas enters the hollow disc 19. After the gas is filtered and adsorbed, it will be transported back to the extrusion cylinder 2 with the cooperation of the second fan 23, outlet pipe 25, second gas pipe, exhaust port and inlet 27, thus forming a gas circulation, thereby continuously processing the gas in the extrusion cylinder 2. Through the setting of the movable rod 18 and the drive unit, the hollow disc 19 can be rotated, so that the gas comes into contact with the reaction solution at different positions. At the same time, the drive unit will cause the sleeve 38 to rotate, and the sleeve 38 will cause the cutting blade 40 to move in a circle through the L-shaped plate 39, cutting the bubbles, thereby refining the bubble size, increasing the gas-liquid contact area, effectively improving the reaction efficiency and enhancing the separation effect.

[0041] like Figure 6As shown, the drive unit includes a servo motor 4 mounted on the side of the base 1. The top of the base 1 has a mounting groove, in which a rotating shaft 7 is rotatably mounted. One end of the rotating shaft 7 is fixedly connected to the output shaft of the servo motor 4. A reciprocating threaded sleeve 32 is fixedly sleeved on the rotating shaft 7. A movable seat 33 is threadedly sleeved on the reciprocating threaded sleeve 32. A first rack 34 and a second rack 36 are mounted on the side of the movable seat 33. The second rack 36 is located above the first rack 34. The bottom end of the movable rod 18 extends to the outside of the sleeve 38 and is equipped with a first gear 35. The first gear 35 meshes with the first rack 34. A second gear 37 is mounted on the bottom end of the sleeve 38. The second gear 37 meshes with the second rack 36. A degassing element adapted to the extrusion cylinder 2 is provided on the base 1. The degassing element is installed in conjunction with the rotating shaft 7.

[0042] Specifically, the servo motor 4 drives the rotating shaft 7 to rotate, and the rotating shaft 7 drives the moving seat 33 to move back and forth through the reciprocating threaded sleeve 32. The moving seat 33 causes the first gear 35 and the second gear 37 to rotate simultaneously through the first rack 34 and the second rack 36, thereby causing the movable rod 18 and the sleeve 38 to rotate simultaneously. In this embodiment, the reciprocating threaded sleeve 32 continuously rotates in one direction, which realizes the reciprocating motion of the moving seat 33, which is the prior art.

[0043] like Figure 6 As shown, a guide rod is installed in the mounting slot. The guide rod is parallel to the rotating shaft 7, and the movable seat 33 is slidably connected to the guide rod.

[0044] In this design, the guide rod provides a guiding function, allowing the movable seat 33 to move more stably in the horizontal direction during use.

[0045] like Figure 6 As shown, the module of the first gear 35 is the same as that of the second gear 37, and the number of teeth of the first gear 35 is greater than the number of teeth of the second gear 37.

[0046] In this design, the rotational speed of the movable rod 18 is less than the rotational speed of the sleeve 38 by setting the gear ratio of the first gear 35 and the second gear 37.

[0047] Specifically, when the first rack 34 and the second rack 36 move, the first gear 35 and the second gear 37 will rotate. At this time, due to the gear ratio of the first gear 35 and the second gear 37, the rotation speed of the first gear 35 will be less than that of the second gear 37. Consequently, the rotation speed of the movable rod 18 will be less than that of the sleeve 38, thus making the rotation speed of the hollow disk 19 less than that of the cutting blade 40, preventing the cutting blade 40 from rotating at the same speed as the hollow disk 19 and affecting the cutting effect.

[0048] like Figure 3 , Figure 5and Figure 6 As shown, the degassing element includes a turntable 8 installed at one end of a rotating shaft 7. An eccentric shaft 9 is eccentrically installed on one side of the turntable 8. A connecting rod 10 is rotatably sleeved on the eccentric shaft 9. A telescopic rod 11 is installed on the top of the base 1. A lifting block 12 is installed at the end of the telescopic rod 11. The other end of the connecting rod 10 is rotatably installed at the bottom of the lifting block 12. A lifting plate 13 is installed on the side of the lifting block 12. Multiple insertion rods 14 are installed at the bottom of the lifting plate 13. Multiple insertion holes are opened on the top of the extrusion cylinder 2. Each insertion hole is equipped with a fixed tube 15 corresponding to one of the insertion rods 14. The lower end of each insertion rod 14 can slide into the corresponding fixed tube 15.

[0049] Specifically, as the rotating shaft 7 rotates, the lifting plate 13 moves up and down repeatedly, which in turn causes the insertion rod 14 to move up and down continuously. Under the action of the fixed tube 15, the insertion rod 14 continuously inserts into the molten raw material in the extrusion cylinder 2, thereby causing the bubbles wrapped in the melt to burst. Then, the gas is released by the shearing effect of the melt flow, thus avoiding the impact of bubble inclusion on product quality.

[0050] like Figure 7 and Figure 9 As shown, the fixing unit includes a sector-shaped block 29 installed on the outer wall of the gas pipe 20. The sector-shaped block 29 has two movable cavities. Sliding blocks 42 are slidably installed in each of the two movable cavities. Moving rods 41 and locking blocks 43 are respectively installed on opposite sides of the two sliding blocks 42. The locking blocks 43 are located on the side closer to the gas pipe 20, and the top of the locking blocks 43 is inclined from top to bottom towards the gas pipe 20. The other ends of the two moving rods 41 extend outside the sector-shaped block 29 and are equipped with pull plates. Limiting plates 44 are installed at the bottom of the two sector-shaped housings 30. The top of the sector-shaped block 29 has two limiting grooves that communicate with the movable cavities. The sides of the two limiting plates 44 are provided with slots. Springs 45 are installed on the side of the two sliding blocks 42 away from the locking blocks 43. The springs 45 are sleeved on the outside of the moving rods 41.

[0051] Specifically, the locking block 43 can be moved by the pull plate and the moving rod 41, so that the locking block 43 is separated from the slot, thereby canceling the limitation of the limiting plate 44. During installation, the limiting plate 44 moves downward and presses the top of the locking block 43. With the help of the spring 45, the locking block 43 moves to avoid the lock and then resets and extends into the slot, thereby fixing the limiting plate 44. This makes it easier to replace the activated carbon 31 and reduces the replacement time.

[0052] like Figure 8As shown, a partition plate 46 is installed on the inner wall of the first processing chamber 16. A flow hole is formed in the middle of the partition plate 46, and a mesh demister 47 is installed on the inner wall of the flow hole. Three fixing holes are formed on the air supply pipe 20, and heat-conducting plates 48 are installed on each of the three fixing holes. The heat-conducting plates 48 are located inside the flow hole and above the mesh demister 47. In this embodiment, the partition plate 46 is located between the first processing chamber 16 and the second processing chamber 17.

[0053] Specifically, the first processing chamber 16 and the second processing chamber 17 can be separated by the partition plate 46, so that the gas can only enter the second processing chamber 17 through the flow hole. At the same time, the flowing gas will come into contact with the mesh demister 47 and the heat-conducting plate 48. At this time, the fine mesh layer of the mesh demister 47 can efficiently trap water vapor droplets carried in the gas, while the heat-conducting plate 48 will absorb the residual heat of the high-temperature gas in the tube in real time and form heat conduction, so as to exchange heat with the gas after the demisting treatment to improve the activity of the activated carbon 31.

[0054] like Figure 1 and Figure 4 As shown, a sealing door 6 is hinged to the side of the processing box 5, and a drain pipe connected to the first processing chamber 16 is fixed to the bottom of the processing box 5. A valve is fixed to the drain pipe.

[0055] In this design, the sealing door 6 and the drain pipe facilitate the maintenance of the components inside the processing chamber 5, and the drain pipe facilitates the treatment of the solution after reaction in the first processing chamber 16.

[0056] The injection molding process of a twin-screw extrusion molding machine for injection molding tubes includes the following steps:

[0057] S1: Before use, the raw materials and reaction solution are poured into the feed hopper and the processing chamber 5 respectively. The reaction solution is only introduced into the first processing chamber 16. The reaction solution can be sodium carbonate solution, sodium bicarbonate solution, and organic weak base solution (such as triethanolamine). After the raw materials enter the feed hopper, they enter the extrusion cylinder 2 under the action of gravity. Then, the screw column 49 is rotated by the drive box 3, which pushes the raw materials forward. During this process, the segmented heater outside the extrusion cylinder 2 is set with independent control of multiple segments, so as to realize the gradient heating of the raw materials. Through precise temperature control, the raw materials are gradually softened and melted. The molten raw materials continue to move forward under the action of screw shearing and conveying, and finally are uniformly extruded through the forming flow channel of the extruder head, thus extruding and forming.

[0058] S2: When heating, the servo motor 4 is started. The start of the servo motor 4 will cause the rotating shaft 7 to rotate. The rotation of the rotating shaft 7 will cause the insert rod 14 to move up and down continuously, thereby continuously inserting the molten raw material in the extrusion cylinder 2, which will cause the bubbles wrapped in the melt to burst. Then, the shear effect of the melt flow will be used to make the gas escape, thereby avoiding the impact of bubble inclusion on product quality.

[0059] S3: Start the first fan 22 and the second fan 23. The output of the first fan 22 will cause the gas in the extrusion cylinder 2 to be discharged from multiple vents on the hollow disc 19 and come into contact with the reaction solution. At this time, the reaction solution will react with hydrogen chloride, while vinyl chloride monomer and dioxin will not react with the reaction solution and will continue to move. After passing through the mesh demister 47 and the heat conduction plate 48, the moisture in the gas will be removed. The gas will continue to move and come into contact with activated carbon 31. Activated carbon 31 will adsorb and filter vinyl chloride monomer and dioxin in the gas. The adsorbed gas will then be discharged into the extrusion cylinder 2 through the second fan 23, the gas outlet 25, the exhaust port, the gas inlet 27 and the second gas pipe, thereby separating and filtering hydrogen chloride, vinyl chloride monomer and dioxin, so as to avoid interference caused by uniform filtration and affect the removal efficiency.

[0060] S4: Simultaneously, the rotation of the shaft 7 will cause the hollow disk 19 to rotate. The rotation of the hollow disk 19 will cause the gas to come into contact with the reaction solution at different positions. The rising gas will first be blocked by the annular plate 28, and then dispersed and moved upward through the vent holes, so that the gas is evenly diffused. At the same time, the rotation of the hollow disk 19 will cause the two sector shells 30 to rotate through the gas delivery pipe 20. The rotation of the two sector shells 30 will cause the activated carbon 31 to move, thereby causing the gas to come into contact with the activated carbon 31 at different positions, so that the gas, reaction solution and activated carbon 31 are fully in contact, avoiding local contact filtration and affecting the filtration effect.

[0061] S5: When the rotating shaft 7 rotates, the cutting blade 40 will move in a circular motion. The circular motion of the cutting blade 40 will cut the bubbles, thereby refining the bubble size, increasing the gas-liquid contact area, improving the reaction efficiency, and enhancing the separation effect.

[0062] The working principle of this device is as follows: Before use, the raw materials and reaction solution are poured into the feed hopper and processing tank 5 respectively. After the raw materials enter the feed hopper, they will enter the extrusion cylinder 2 under the action of gravity. Then, the screw column 49 is rotated by the drive box 3. At this time, the meshing rotation of the screw column 49 forms forced conveying, pushing the solid raw materials in the extrusion cylinder 2 forward along the axial direction. During this process, the segmented heater outside the extrusion cylinder 2 simultaneously heats the raw materials in a gradient. Through precise temperature control, the raw materials are gradually softened and melted. The raw materials in the molten state continue to move forward under the shearing and conveying action of the screw, and finally are uniformly extruded through the forming flow channel of the extruder head, thus forming the extrusion.

[0063] During heating, servo motor 4, first fan 22, and second fan 23 are activated. The activation of servo motor 4 causes shaft 7 to rotate, which in turn causes turntable 8 to rotate. Turntable 8 causes eccentric shaft 9 to rotate in a circular motion. This circular motion of eccentric shaft 9 provides a force to lifting block 12 via connecting rod 10. Under the force of the telescopic rod 11, lifting block 12 moves up and down continuously. This movement causes lifting plate 13 to move up and down continuously, which in turn causes insertion rod 14 to move up and down continuously. Under the action of fixed tube 15, insertion rod 14 continuously pushes the molten material inside extrusion cylinder 2, thereby encapsulating... The bubbles in the melt burst, and the shear effect of the melt flow causes the gas to escape, thus avoiding the impact of bubble inclusion on product quality. Simultaneously, the first blower 22 outputs gas generated by the heating of the raw material and the overflowing bubbles from the extrusion cylinder 2 through the inlet pipe 24, outlet 26, and first gas pipe to the rotary joint 21. The gas continues to flow and is output through the gas delivery pipe 20 to the hollow disc 19, then exits through multiple vents and comes into contact with the reaction solution. The reaction solution reacts with hydrogen chloride, while vinyl chloride monomer and dioxins do not react with the reaction solution and continue to move. The gas continues to move and enters the second processing chamber 17, where it is first circulated... The gas is blocked by the plate 28 and then dispersed upwards through the vent holes, thus achieving uniform diffusion. The gas continues to rise and comes into contact with the activated carbon 31. Upon contact, the activated carbon 31 adsorbs and filters vinyl chloride monomer and dioxins in the gas. The adsorbed gas then passes through the second fan 23, the outlet pipe 25, the exhaust port, the inlet port 27, and the second gas pipe into the extrusion cylinder 2, further separating and filtering hydrogen chloride, vinyl chloride monomer, and dioxins. This avoids interference from uniform filtration, which could affect removal efficiency. Simultaneously, when the rotating shaft 7 rotates, it causes the reciprocating threaded sleeve 32 to rotate. The rotation of the reciprocating threaded sleeve 32, under the action of the guide rod, causes the moving seat 33 to reciprocate. The reciprocating movement of the first rack 34 causes the first gear 35 to rotate, which in turn causes the movable rod 18 to rotate. This rotation of the movable rod 18 causes the hollow disk 19 to rotate, thus bringing the gas into contact with the reaction solution at different locations. Simultaneously, the rotation of the hollow disk 19 causes the gas delivery pipe 20 to rotate, which in turn causes the two sector shells 30 to rotate via the sector block 29. This rotation of the two sector shells 30 causes the activated carbon 31 to move, bringing the gas into contact with the activated carbon 31 at different locations. This ensures that the gas, reaction solution, and activated carbon 31 are in full contact, avoiding localized contact filtration that could affect the filtration effect.

[0064] When the movable seat 33 reciprocates, it drives the second rack 36 to reciprocate. The reciprocating movement of the second rack 36 causes the second gear 37 to rotate. The reciprocating rotation of the second gear 37 causes the sleeve 38 to rotate. The rotation of the sleeve 38 causes the L-shaped plate 39 to move in a circular motion. The circular motion of the L-shaped plate 39 causes the cutting blade 40 to move in a circular motion. The circular motion of the cutting blade 40 cuts the bubbles, thereby refining the bubble size, increasing the gas-liquid contact area, effectively improving the reaction efficiency, and enhancing the separation effect.

[0065] After the gas reacts with the reaction solution, it will come into contact with the mesh demister 47 during its ascent. At this time, the fine mesh layer of the mesh demister 47 can efficiently trap water vapor droplets carried in the gas. At the same time, the heat-conducting plate 48 arranged in the gas delivery pipe 20 absorbs the residual heat of the high-temperature gas in the pipe in real time and forms heat conduction, thus exchanging heat with the gas after the demisting treatment.

[0066] When activated carbon 31 needs to be replaced, pull the pull plate. The movement of the pull plate will cause the moving rod 41 to move, which in turn will cause the sliding block 42 to move. The movement of the sliding block 42 will cause the locking block 43 to move. When the locking block 43 moves out of the slot, the limiting plate 44 is no longer limited. Then the limiting plate 44 is moved out, which in turn moves the sector housing 30 out. After it is moved out, release the pull plate, and the sliding block 42 will return to its original position under the action of the spring 45. Then the limiting plate 44 on the new sector housing 30 is inserted into the limiting slot. When the limiting plate 44 contacts the locking block 43, the continued movement of the limiting plate 44 will squeeze the locking block 43 and make it move. When the slot is aligned with the locking block 43, the locking block 43 will return to its original position under the action of the spring 45, which will then fix the limiting plate 44, thus facilitating the replacement of activated carbon 31 and reducing replacement time.

[0067] The above embodiments only illustrate one or more implementations of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this patent should be determined by the appended claims.

Claims

1. A twin-screw extrusion molding machine for injection-molded pipes, comprising a base (1), characterized in that: The top of the base (1) is equipped with a drive box (3), and the side of the drive box (3) is equipped with a screw column (49) through a gear set. The side of the drive box (3) is equipped with an extrusion cylinder (2). The top and side of the extrusion cylinder (2) are respectively equipped with a feed hopper and an extruder head. A heater is fixed on the extrusion cylinder (2), and a gas processing mechanism is provided on the base (1). The gas processing mechanism includes a processing box (5) installed on the top of the base (1). The processing box (5) has a first processing chamber (16) and a second processing chamber (17) connected from bottom to top. The first processing chamber (16) and the second processing chamber (17) are respectively provided with a hollow disc (19) and two fan-shaped shells (30). Activated carbon (31) is fixed on both of the two fan-shaped shells (30). An annular plate (28) is installed in the second processing chamber (17). Multiple air vents are opened on both the hollow disc (19) and the annular plate (28). The base (1) is provided with a drive air intake assembly that makes the hollow disc (19) and the two fan-shaped shells (30) rotate. The drive air intake assembly includes a mounting hole on the top of the hollow disc (19), on which an air supply pipe (20) is installed. Two fan-shaped housings (30) are fixedly connected to the air supply pipe (20) via a fixing unit. The top of the air supply pipe (20) extends to the outside of the processing box (5) and is fitted with a rotary joint (21). An exhaust port is provided at the bottom of the processing box (5). A first fan (22) and a second fan (23) are installed on the top of the processing box (5). An air outlet (26) and an air inlet (27) are provided on the top of the extrusion cylinder (2). An air inlet pipe (24) and a first air pipe are respectively installed at the inlet and outlet ends of the first fan (22). The other ends of the air inlet pipe (24) and the first air pipe are respectively connected to the air outlet (26) and the rotary joint (21). The second fan (23) is connected to the inlet and outlet ends of the second air pipe and the outlet pipe (25), respectively. The second air pipe and the outlet pipe (25) are connected to the exhaust port and the air inlet (27), respectively. The air outlet (26) and the air inlet (27) are both equipped with filters. The bottom of the processing box (5) is provided with a drive hole. A sleeve (38) is rotatably installed on the drive hole. Two L-shaped plates (39) are installed on the outside of the sleeve (38). A cutting blade (40) is installed on the top of the two L-shaped plates (39). A movable rod (18) is rotatably installed inside the sleeve (38). The hollow disc (19) is installed on the top of the movable rod (18). The base (1) is provided with a drive unit that makes the movable rod (18) and the sleeve (38) rotate.

2. The twin-screw extrusion molding machine for injection-molded pipes according to claim 1, characterized in that, The drive unit includes a servo motor (4) mounted on the side of the base (1). A mounting groove is provided on the top of the base (1), and a rotating shaft (7) is rotatably mounted in the mounting groove. One end of the rotating shaft (7) is connected to the output shaft of the servo motor (4). A reciprocating threaded sleeve (32) is fitted onto the rotating shaft (7), and a movable seat (33) is threaded onto the reciprocating threaded sleeve (32). A first rack (34) and a second rack (36) are mounted on the side of the movable seat (33). The movable rod ( The bottom end of 18) extends to the outside of the sleeve (38) and is equipped with a first gear (35). The first gear (35) meshes with the first rack (34). The bottom end of the sleeve (38) is equipped with a second gear (37). The first gear (35) and the second gear (37) mesh with the first rack (34) and the second rack (36) respectively. The base (1) is provided with a degassing element that is compatible with the extrusion cylinder (2). The degassing element is installed in conjunction with the rotating shaft (7).

3. The twin-screw extrusion molding machine for injection-molded tubes according to claim 2, characterized in that, A guide rod is installed in the mounting slot, and the movable seat (33) is slidably connected to the guide rod.

4. The twin-screw extrusion molding machine for injection-molded pipes according to claim 2, characterized in that, The number of teeth of the first gear (35) is greater than the number of teeth of the second gear (37).

5. The twin-screw extrusion molding machine for injection-molded pipes according to claim 2, characterized in that, The degassing element includes a turntable (8) installed at one end of the rotating shaft (7), an eccentric shaft (9) is eccentrically installed on the side of the turntable (8), a connecting rod (10) is rotatably sleeved on the eccentric shaft (9), a telescopic rod (11) is installed on the top of the base (1), a lifting block (12) is installed at the end of the telescopic rod (11), the other end of the connecting rod (10) is rotatably installed at the bottom of the lifting block (12), a lifting plate (13) is installed on the side of the lifting block (12), a plurality of insert rods (14) are installed at the bottom of the lifting plate (13), a plurality of insertion holes are opened on the top of the extrusion cylinder (2), and a fixing tube (15) adapted to the insert rod (14) is installed on each of the plurality of insertion holes.

6. The twin-screw extrusion molding machine for injection-molded pipes according to claim 1, characterized in that, The fixing unit includes a sector block (29) installed on the outer wall of the gas pipe (20). The sector block (29) has two movable cavities. Sliding blocks (42) are slidably installed in both movable cavities. Moving rods (41) and locking blocks (43) are respectively installed on the two sides of the two sliding blocks (42) that are far apart from each other. The other ends of the two moving rods (41) extend to the outside of the sector block (29) and are equipped with pull plates. Limiting plates (44) are installed at the bottom of the two sector housings (30). The top of the sector block (29) has two limiting grooves that communicate with the movable cavities. The sides of the two limiting plates (44) are provided with slots. Springs (45) are installed on the sides of the two sliding blocks (42). The other ends of the two springs (45) are respectively installed on the inner side walls of the two movable cavities.

7. The twin-screw extrusion molding machine for injection-molded pipes according to claim 1, characterized in that, A partition plate (46) is installed on the inner side wall of the first processing chamber (16). A flow hole is provided in the middle of the partition plate (46), and a mesh demister (47) is installed in the flow hole.

8. The twin-screw extrusion molding machine for injection-molded pipes according to claim 1, characterized in that, A sealing door (6) is hinged to the side of the processing box (5), and a drain pipe connected to the first processing chamber (16) is fixed to the bottom of the processing box (5), and a valve is fixed to the drain pipe.

9. A process for producing injection-molded pipes using a twin-screw extrusion molding machine according to any one of claims 1-8, characterized in that, Includes the following steps: S1: Before use, pour the raw materials and reaction solution into the feed hopper and the processing box (5) respectively. After the raw materials enter the feed hopper, they will enter the inside of the extrusion cylinder (2) under the action of gravity. Then, the screw column (49) is rotated by the drive box (3), which pushes the raw materials forward. During this process, the heater on the extrusion cylinder (2) heats the raw materials in a gradient. Finally, the raw materials are uniformly extruded through the forming channel of the extruder head, thus forming the extrusion. S2: The gas in the extrusion cylinder (2) is sent into the hollow disk (19) and discharged from multiple vent holes on the hollow disk (19) and comes into contact with the reaction solution. At this time, the reaction solution reacts with hydrogen chloride. Then the gas that has removed moisture continues to move and comes into contact with activated carbon (31). Activated carbon (31) adsorbs and filters vinyl chloride monomer and dioxin in the gas. The adsorbed gas is sent back into the extrusion cylinder (2). S4: The hollow disk (19) rotates, so that the gas comes into contact with the reaction solution at different positions. Then the rising gas is first blocked by the annular plate (28), and then dispersed and moved upward through the vent holes, so that the gas diffuses evenly.

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