Polymer material processing equipment and processing method

Abstract

The application discloses a kind of high polymer material processing equipment, including screw, multiple microbead holes are arranged between the thread gap of the screw, the inside of the screw is hollow, and the inside of the screw is provided with microbead groove communicated with microbead hole, and microbead extrusion device is arranged in microbead groove.The application also discloses a kind of high polymer material processing method.Adopt the high polymer material processing equipment and processing method described in the application, ceramic microbead as physical raw material can be added while heating semi-solid high polymer material, ceramic microbead is directly added using microbead extrusion device, and ceramic microbead has good uniformity, solves the technical problem of ceramic microbead difficult to be added with solid or fluid material, and improves the manufacturing process of high polymer material.

Description

Technical Field

[0001] This invention belongs to the field of materials processing technology, specifically relating to a polymer material processing equipment and processing method. Background Technology

[0002] Polymer materials, especially ultra-high molecular weight materials such as ultra-high molecular weight polyethylene pipes, have excellent mechanical properties, high specific strength, good wear resistance, and high impact resistance; they are also chemically stable and highly corrosion resistant; and they have excellent non-stick and self-lubricating properties, making them widely used in the transportation of powders, slurries, liquids, and gases in industries such as coal, petrochemicals, thermal power generation, and public utilities.

[0003] Existing technologies, such as CN108314822 A, disclose a high-temperature resistant ultra-high molecular weight polyethylene (UHMWPE) pipe and its preparation method. This method addresses the technical problems of extremely high melt viscosity, poor fluidity, slow extrusion molding speed, large coefficient of linear expansion, and poor dimensional stability of extruded pipes in high-molecular-weight materials. It also addresses the warping and changes in cross-sectional dimensions of extruded pipes after cooling and shrinkage, leading to difficulties in subsequent connections. The improved process method incorporates ceramic microspheres to restrict the thermal motion of polyethylene molecules, thereby increasing the heat distortion temperature and flame retardancy of the UHMWPE pipe and improving its dimensional stability.

[0004] However, the applicant discovered that when ceramic microspheres are directly mixed with other raw materials, the ceramic microspheres tend to stick together with some of the components during the mixing process, resulting in uneven distribution. During the subsequent heating process, the difference in thermal expansion coefficients between the ceramic microspheres and other materials is significant. During the mixing and heating process, ceramic microspheres that are close together are easily squeezed and agglomerated, further causing the ceramic microspheres to concentrate. These concentration points of ceramic microspheres are likely to become stress concentration points in the subsequently generated materials, causing them to break or develop defects first. Summary of the Invention

[0005] To overcome the technical defects of the existing technology, this invention discloses a polymer material processing equipment and processing method.

[0006] The polymer material processing equipment of the present invention includes a screw, characterized in that a plurality of microbead holes are provided between the thread gaps of the screw, the screw is hollow inside, a microbead groove communicating with the microbead holes is provided inside the screw, and a microbead extrusion device is provided in the microbead groove.

[0007] Preferably, the screw includes a housing, on which an electric heating layer is provided.

[0008] Preferably, the screw housing is provided with a heat insulation layer located outside the electric heating layer.

[0009] Preferably, the microsphere extrusion device includes an air channel disposed in the center of the microsphere groove, and a plurality of annular air bladders surrounding the air channel and communicating with the air channel through an air guide channel, wherein the direction of the air bladders is consistent with the direction of the thread gap.

[0010] Preferably, the central angle of the annular airbag is 360 degrees, and there are multiple air channels that are evenly distributed at equal central angle intervals.

[0011] Preferably, a connecting valve is provided at the end of the airway, and the connecting valve is connected to an air pump, the exhaust port of the air pump being connected to the microbead groove.

[0012] Preferably, it also includes a propulsion device for rotating the screw, the propulsion device comprising a pair of cooperating bevel gears, the shafts of the two bevel gears being connected to the screw and the motor respectively.

[0013] Preferably, the microbead hole is a tapered hole with the small end facing the thread gap, and the outer wall of the microbead groove is made of elastic material.

[0014] Preferably, the microbeads are uniformly distributed in a two-dimensional array, and the distance between the centers of adjacent microbeads is 2-5 times the diameter of the microbeads.

[0015] This invention also discloses a method for processing polymer materials, comprising the following steps: Step 1. Inject polymer material into the screw, turn on the heating device, and inject microbeads into the microbead groove; Step 2. Turn on the air pump to pressurize the airway and inflate the airbag. The air injection speed and the screw forward speed should meet the following relationship: during the time it takes for the airbag to expand and squeeze out a microbead, the screw forward distance is greater than the diameter of a microbead. Step 3. After the air pump reaches the set value, the screw stops moving forward and the air pump evacuates the air bag. During the evacuation process, the air pump simultaneously inflates the microbead groove. Step 4. After the airbag is evacuated, add microbeads to the microbead groove. After replenishment, the screw continues to advance and returns to step 2.

[0016] Using the polymer material processing equipment and method described in this invention, ceramic microspheres, which serve as physical raw materials, can be added while heating semi-solidified polymer materials. The ceramic microspheres are directly added using a microsphere extrusion device, resulting in good uniformity of ceramic microsphere distribution. This solves the technical problem of unevenly distributing ceramic microspheres in solid or fluid materials and improves the manufacturing process of polymer materials. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of a specific embodiment of the polymer material processing equipment described in this invention; Figure 2This is a cross-sectional schematic diagram of a specific embodiment of the polymer material processing equipment described in this invention; Figure 3 This is a schematic diagram of a specific embodiment of the screw described in this invention; Figure 4 This is a schematic cross-sectional view of the internal structure of a specific embodiment of the screw described in this invention; Figure 5 For the present invention Figure 2 Enlarged diagram of point A in the diagram; The attached figures are labeled as follows: 1. Outer shell; 11. Discharge hopper; 12. Outer shell fixing seat; 13. Insulation layer; 2. Screw; 21. Screw fixing seat; 22. Air passage; 221. Air guide passage; 23. Airbag; 24. Thread; 25. Microbead hole; 26. Microbead groove; 27. Electric heating layer; 3. Raw material feed seat; 31. Microbead feed seat; 4. Propulsion device; 41. Motor; 42. Connecting valve. Detailed Implementation

[0018] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0019] The polymer material processing equipment of the present invention includes a screw 2, a plurality of microbead holes 25 are provided between the thread gaps of the screw, the screw is hollow inside, and a microbead groove 26 communicating with the microbead holes is provided inside the screw, and a microbead extrusion device is provided in the microbead groove.

[0020] Here, thread clearance refers to the portion of the cylindrical surface of screw 2 that does not cover the thread 24, such as... Figure 3 As shown, an array of microbeads 25 are arranged between the thread gaps, and an electric heating layer 27 located on the outside of the screw is provided inside the outer shell of the screw. While the screw rotates and heats the material, the material is pushed towards the discharge hopper 11 according to the rotation direction of the thread.

[0021] Figure 1 In the specific embodiment shown, the screw 2 is fixed to the mounting surface of the device via the screw fixing seat 21, and the screw housing 1 is fixed to the mounting surface of the device via the housing fixing seat 12. Raw materials and microspheres can be added to the screw and the microsphere groove respectively through the raw material feed seat 3 and the microsphere feed seat 31.

[0022] An annular end cap can be installed at the top of the microbead groove to seal the microbead groove. A microbead feed seat is provided on the annular end cap, through which microbeads are added into the microbead groove.

[0023] Ceramic microspheres are added to the microsphere groove 26. While the material is heated, the microsphere extrusion device is turned on, continuously extruding the ceramic microspheres into the threaded gap. As the material advances, it continuously carries away the microspheres extruded from the microsphere holes. By controlling the screw speed and the frequency of microsphere extrusion, the microspheres and solid material are mixed. In a preferred embodiment, the height of the thread is designed to be very thin, which can be 2-4 times the diameter of the microspheres, to maximize the uniform distribution of microspheres in the material.

[0024] Figure 3 In the specific embodiment shown, the microbeads are uniformly distributed in a two-dimensional array, and the center-to-center distance between adjacent microbeads is 2-5 times the diameter of the microbeads, so that the discharged microbeads do not get too close to each other and maintain a high distribution density.

[0025] The heating layer inside the screw casing is generally an electric heating layer. An insulation layer 13 can be set between the electric heating layer and the casing to keep the inside of the screw warm.

[0026] To address the technical problems associated with microbead extrusion, this invention discloses a microbead extrusion device, such as... Figure 1 and 4 As shown, it includes an air channel 22 located in the center of the microbead groove, and multiple annular air bladders 23 surrounding and communicating with the air channel. The orientation of the air bladders 23 is consistent with the orientation of the thread gap. The thread gap can be seen as a continuous splicing of multiple rings with deviations at the starting and ending points. The corresponding shape of the airbag design is a ring-shaped airbag with multiple starting and ending points with deviations. When the central angle of the circle is 360 degrees, the ring-shaped airbag is easy to fix and can be simultaneously inhaled from multiple air guides distributed on the airway, so that the airbag expands evenly. The airbag can be fixed to the outside of the airway by adhesive by connecting through the air guides 221. There are multiple air guides 221, which are evenly distributed on the above-mentioned rings. For example, they can be set to 4, 6 or 8, so that the airbag can be inflated at the same time, so that the airbag expands evenly.

[0027] The diameter of the airway can be designed to be relatively large to facilitate rapid inflation and minimize the time difference in expansion between different parts of the airway. The connection between the airway and the air pump should preferably be a straight-through connection, with the air pump's air outlet direction aligned with the direction of the airway, so that the airway can quickly take in air and inflate all the airbags almost simultaneously.

[0028] In use, the airway is connected to an external air pump via the connecting valve 42 at the end of the airway. The microbead groove is connected to the microbead filling device. The microbead groove is filled with microbeads. The air pump inflates the air bladder, causing the air bladder to expand and expel the microbeads through the microbead holes.

[0029] The inflation speed can be calculated based on the airbag volume and the diameter of the microspheres. During the process of slowly inflating the airbag, multiple microspheres are continuously extruded from the microsphere holes, and the screw advance distance during the interval between extrusions is greater than the diameter of a single microsphere, so that the microspheres are not distributed in the same position on the material that has been shaped into a flat strip by the screw thread.

[0030] like Figure 5 As shown, give Figure 1 The enlarged schematic diagram at point A, near the air passage, shows the polymer material spiraling forward along the thread 24 between the thread gaps. The air pump continuously inflates the air passage 22, and the compressed gas in the air passage inflates the airbag 23 through the air guide 221. The microbead groove 26 is constantly filled with airbags and microbeads. The airbag expands and occupies the space in the microbead groove, causing the microbeads to be discharged through the microbead holes 25 into the thread gaps. Multiple microbeads are simultaneously squeezed out of multiple microbead holes by the airbags.

[0031] When the airbag inflates to a certain upper limit, the screw can stop moving forward, and the air pump can quickly evacuate the airbag. During the evacuation process, the air pump simultaneously fills the microbead groove with air to fill the microbead groove caused by the airbag's contraction, preventing microbeads or materials from shrinking into the microbead groove through the microbead holes. In a preferred embodiment, the air pump exhaust port connected to the connecting valve is connected to the microbead groove, which can realize that the air pump draws air from the airbag and discharges the drawn air into the microbead groove at the same time, so that the microbead groove is filled with air while the airbag contracts, preventing the air pressure in the microbead groove from dropping rapidly.

[0032] After the airbag is evacuated, the microbead filling device replenishes and fills the microbead groove 26 with microbeads. The microbead hole can preferably be designed as a conical hole with the small mouth facing the thread gap. The material of the microbead groove can be a metal material with a certain elasticity or a high-temperature resistant polymer material. The diameter of the microbead hole is designed to be slightly smaller than the microbead hole. When the airbag expands, the microbeads are squeezed out by the expansion of the microbead hole, thus avoiding the microbeads being sucked back when the airbag contracts.

[0033] Based on the polymer material processing equipment described in this invention, the following processing method can be adopted, including the following steps: Step 1. Inject polymer material into the screw, turn on the heating device, and inject microbeads into the microbead groove; Step 2. Turn on the air pump to pressurize the airway and inflate the airbag. The air injection speed and the screw forward speed should meet the following relationship: during the time it takes for the airbag to expand and squeeze out a microbead, the screw forward distance is greater than the diameter of a microbead. Step 3. After the air pump reaches the set value, the screw stops moving forward and the air pump evacuates the air bag. During the evacuation process, the air pump simultaneously inflates the microbead groove. Step 4. After the airbag is evacuated, add microbeads to the microbead groove. After replenishment, the screw continues to advance and returns to step 2.

[0034] Figure 1 In the specific embodiment shown, the propulsion device 4 for rotating the screw includes a pair of cooperating bevel gears. The shafts of the two bevel gears are respectively connected to the screw and the motor 41. The output direction is changed by the pair of bevel gears, which is a prior art in the field and will not be described in detail here.

[0035] In this invention, the design of bevel gear output allows the motor to no longer be located on the screw axis, making it easier to install the air pump on the screw axis. Since the air pump needs to be quickly and directly aligned with the air passage for inflation and deflation, the air pump and its inlet and outlet directions are preferably the same as the axial direction of the air passage.

[0036] At the same time, the bevel gear design not only allows the motor to be installed next to the screw and drive the screw to rotate, but also enables the adjustment of the screw speed and torque through the tooth ratio of the two bevel gears. For example, it can achieve a rotational output with reduced speed but increased torque.

[0037] Using the polymer material processing equipment described in this invention, ceramic microspheres, which serve as physical raw materials, can be added while heating semi-solidified polymer materials. The ceramic microspheres are added directly using a microsphere extrusion device, resulting in good uniformity of ceramic microsphere distribution. This solves the technical problem of the difficulty in uniformly distributing ceramic microspheres in solid or fluid materials, and improves the manufacturing process of polymer materials.

[0038] The foregoing descriptions are preferred embodiments of the present invention. Unless there is a clear contradiction between the preferred embodiments or a prerequisite for a particular preferred embodiment, the preferred embodiments can be arbitrarily combined and used. The embodiments and specific parameters described are only for clearly illustrating the inventor's invention verification process and are not intended to limit the scope of patent protection of the present invention. The scope of patent protection of the present invention shall still be determined by its claims. Similarly, any equivalent structural changes made based on the description and drawings of the present invention shall also be included within the scope of protection of the present invention.

Claims

1. A polymer material processing device, comprising a screw (2), characterized in that... The screw has multiple microbead holes (25) between its thread gaps. The screw is hollow inside and has microbead grooves (26) that communicate with the microbead holes. A microbead extrusion device is installed in the microbead grooves. The microbead extrusion device includes an air passage (22) in the center of the microbead groove (26) and multiple annular air bladders (23) surrounding the air passage and communicating with the air passage (22) through an air guide passage (221). The direction of the air bladders (23) is consistent with the direction of the thread gaps. Once the airbag expands to a certain upper limit, the screw stops moving forward, and the air pump quickly evacuates the airbag. During the evacuation process, the air pump simultaneously fills the microbead groove with air to fill the microbead groove caused by the airbag contraction, preventing the microbeads or materials from shrinking into the microbead groove through the microbead holes.

2. The polymer material processing equipment as described in claim 1, characterized in that, The screw (2) includes a housing (1) and an electric heating layer (27) is provided on the housing.

3. The polymer material processing equipment as described in claim 2, characterized in that, The screw has an insulation layer (13) located outside the electric heating layer (27) inside its outer casing.

4. The polymer material processing equipment as described in claim 1, characterized in that, The central angle of the airbag (23) is 360 degrees, and there are multiple air channels (221) that are evenly distributed at equal central angle intervals.

5. The polymer material processing equipment as described in claim 1, characterized in that, It also includes a propulsion device (4) for rotating the screw, the propulsion device comprising a pair of cooperating bevel gears, the shafts of the two bevel gears being connected to the screw and the motor (41) respectively.

6. The polymer material processing equipment as described in claim 1, characterized in that, The microbead hole (25) is a tapered hole with the small opening facing the thread gap, and the outer wall of the microbead groove (26) is made of elastic material.

7. The polymer material processing equipment as described in claim 1, characterized in that, The microbeads (25) are uniformly distributed in a two-dimensional array, and the distance between the centers of adjacent microbeads is 2-5 times the diameter of the microbeads.

8. A method for processing polymer materials, characterized in that... Based on the polymer material processing equipment as described in any one of claims 1 to 7, the method includes the following steps: Step 1. Inject polymer material into the screw, turn on the heating device, and inject microbeads into the microbead groove; Step 2. Turn on the air pump to pressurize the airway and inflate the airbag. The air injection speed and the screw forward speed should meet the following relationship: during the time it takes for the airbag to expand and squeeze out a microbead, the screw forward distance is greater than the diameter of a microbead. Step 3. After the air pump reaches the set value, the screw stops moving forward and the air pump evacuates the air bag. During the evacuation process, the air pump simultaneously inflates the microbead groove. Step 4. After the airbag is evacuated, add microbeads to the microbead groove. After replenishment, the screw continues to advance and returns to step 2.

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