Screw rod for efficient pipe production
By optimizing the thread structure of the screw, including increasing the helical lift angle and the groove depth in the feed section, setting up liquid-phase grooves and solid-phase grooves in the plasticization section, and installing barriers and mixing sections in the extrusion section, solving the problems of low production efficiency and poor plasticization effect at high speeds, and achieving efficient pipe production.
Patent Information
- Application Number
- CN202510918290.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-03
- Publication Date
- 2025-08-01
AI Technical Summary
Existing screws are difficult to improve production efficiency at high speeds, the plasticization effect of materials is reduced, and the pressure and tensile performance of the pipes are poor.
A screw for efficient pipe production is designed, including feed section, plasticizing section and extrusion section. The threaded structure increases from front to back and the spiral rise angle and groove depth gradually becomes shallow. The plasticized section is equipped with liquid phase tank and solid phase tank, and the extrusion section is equipped with barriers and mixing sections to optimize the thread structure to improve the plasticization quality and output.
Maintain high plasticization quality at high speed and high yield, meet the demand for high-speed and efficient production, and improve the plasticization capacity and output of pipes.
Smart Images
Figure CN120396292A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the technical field of production equipment for plastic pipe products, and particularly relates to a screw for efficient pipe production. Background Art
[0002] The screw is an important component in plastic extrusion molding. The length-diameter ratio, thread structure form, screw speed, etc. of the screw will all affect the plasticization effect of the raw materials and the output of the extruder. With the increase in market demand, the existing screws are difficult to improve production efficiency at high speeds, and the plasticization effect on the materials is reduced, and the pressure resistance and tensile properties of the produced pipes are not good. In order to improve the production efficiency of the screw and the quality of the products, the general trend of current plastic pipe extruders is to increase the length of the plasticization section, increase the screw speed, and deepen the screw groove. Lengthening the plasticization section will extend the residence time of the materials. Increasing the screw speed can effectively increase the output but cannot guarantee the plasticization quality. Deepening the screw groove will reduce the positive conveying efficiency. Therefore, it is necessary to design the thread structure of the screw to ensure the plasticization quality of the materials while increasing the output and production efficiency. Summary of the Invention
[0003] In order to solve the above technical problems, the purpose of this application is to provide a screw for efficient pipe production.
[0004] To achieve the above object, the present application adopts the following technical solution: A screw for efficient pipe production, comprising a rod body extending in the front-rear direction and a thread spirally extending from front to back along the rod body. The rod body is successively an feeding section, a plasticizing section and an extrusion section from front to back. The length of the plasticizing section is greater than the length of the feeding section, the length of the feeding section is greater than the length of the extrusion section, and the length of the plasticizing section is greater than 1 / 2 of the length of the rod body. The outer diameter of the thread is arranged unchanged in the feeding section and the plasticizing section. The helix angle of the thread increases from front to back in the feeding section, and the depth of the trough formed by the thread in the feeding section gradually becomes shallower from front to back. The thread in the plasticizing section is provided with a spirally extending liquid phase trough, and the liquid phase trough divides the thread into a main edge and a secondary edge. The plasticizing section includes a long separation segment and a short separation segment connected successively from front to back. The length of the long separation segment is greater than the length of the short separation segment. The main edge and the secondary edge converge at the front end of the long separation segment, the junction of the long separation segment and the short separation segment, and the rear end of the short separation segment. The volume of the liquid phase trough gradually increases from front to back in the long separation segment and the short separation segment respectively. The extrusion section includes a barrier segment and a mixing segment connected successively from front to back. A plurality of slots spirally extending along the rod body are provided on the barrier segment. The mixing segment is provided with a plurality of mixing groups spaced from front to back. Each mixing group includes a plurality of mixing protrusions arranged successively along the circumference of the rod body.
[0005] In the above technical solution, further preferably, the bottom diameter of the feeding section increases from front to back.
[0006] In the above technical solution, further preferably, the helix angle of the thread in the feeding section is 17.7° - 23°.
[0007] In the above technical solution, further preferably, the rear end face of the main edge and the front end face of the secondary edge define the liquid phase trough, and the rear end face of the secondary edge and the front end face of the main edge define the solid phase trough. The volume of the solid phase trough gradually decreases from front to back in the long separation segment and the short separation segment respectively.
[0008] In the above technical solution, further preferably, the long separation section includes a first half connected to the feeding section and a second half connected to the short separation section. In the first half of the long separation section, the widths of the solid-phase tank and the liquid-phase tank are equal and unchanged from front to back; in the second half of the long separation section, the width of the solid-phase tank gradually decreases from front to back, and the width of the liquid-phase tank gradually increases from front to back; in the short separation section, the width of the solid-phase tank gradually decreases from front to back, and the width of the liquid-phase tank gradually increases from front to back.
[0009] In the above technical solution, further preferably, in the long separation section, the helix angle of the main ridge is equal and unchanged from front to back; in the first half of the long separation section, the helix angle of the secondary ridge is equal to that of the main ridge; in the second half of the long separation section, the helix angle of the secondary ridge is greater than that of the main ridge; in the short separation section, the helix angle of the secondary ridge is greater than that of the main ridge, and the helix angle of the secondary ridge in the short separation section is less than that of the main ridge in the long separation section.
[0010] In the above technical solution, further preferably, the helix angle of the secondary ridge is 26.8° - 32.5°, and the helix angle of the main ridge is 23° - 28°.
[0011] In the above technical solution, further preferably, the length of the barrier section is greater than that of the mixing section.
[0012] In the above technical solution, further preferably, the plurality of grooves include a plurality of intermediate grooves circumferentially spaced along the rod body, and a plurality of feeding grooves and a plurality of discharging grooves parallel to the intermediate grooves. The feeding groove and the discharging groove are arranged along the same center line between two adjacent intermediate grooves. In the rotation direction of the screw, a protruding first barrier is formed between each feeding groove and the downstream intermediate groove, and a protruding second barrier is formed between each discharging groove and the upstream intermediate groove.
[0013] In the above technical solution, further preferably, the mixing protrusions of two adjacent mixing groups are alternately arranged in the circumferential direction of the rod body.
[0014] The present application has the following beneficial effects compared with the prior art:
[0015] The present application ensures that the screw maintains a high plasticizing quality while operating at high speeds and high outputs, meeting the current production requirements of high speed and high efficiency; through the structural optimization of the screw, it is ensured that without increasing the length of the screw and the energy consumption, the plasticizing ability and output of the screw are further enhanced. Brief Description of the Drawings
[0016] Figure 1 Figure 1 is a schematic structural view of a screw for efficient pipe production provided by an embodiment of the present application;
[0017] Figure 2 is Figure 1 a schematic structural view of the feeding section in
[0018] Figure 3 is Figure 1 a schematic structural view of the plasticizing section in
[0019] Figure 4 is Figure 1 an expanded schematic view of the feeding section and the plasticizing section in
[0020] Figure 5 is Figure 1 a schematic structural view of the barrier section in
[0021] Figure 6 is Figure 5 an expanded schematic view of the barrier section in
[0022] Figure 7 is Figure 1 a schematic structural view of the kneading section in
[0023] Figure 8 is a cross-sectional view taken along line A-A in Figure 7 Figure 1.
[0024] Wherein: 100, screw; 1, rod body; 11, feeding section; 12, plasticizing section; 121, long separation section; 122, short separation section; 13, extrusion section; 131, barrier section; 132, kneading section; 2, thread; 21, main ridge; 22, secondary ridge; 31, liquid phase groove; 32, solid phase groove; 41, intermediate groove; 42, feeding groove; 43, discharging groove; 44, first barrier; 45, second barrier; 5, kneading group; 51, kneading protrusion. Detailed Description of the Invention
[0025] To describe in detail the technical content, structural features, achieved objectives and effects of the application, the technical solutions in the embodiments of the present application will be described below in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. In the following description, for the purpose of explanation, many specific details are set forth to provide a detailed description of various exemplary embodiments or implementations of the invention. However, various exemplary embodiments may also be implemented without these specific details or in the case of one or more equivalent arrangements. In addition, various exemplary embodiments may be different, but not necessarily exclusive. For example, without departing from the inventive concept, the specific shapes, structures and characteristics of the exemplary embodiments may be used or implemented in another exemplary embodiment.
[0026] An embodiment of the present application provides a screw for efficient pipe production, as Figure 1 shown. The screw 100 includes a rod body 1 extending in the front-rear direction and a thread 2 spirally extending from front to back along the rod body 1. The rod body 1 is successively an feeding section 11, a plasticizing section 12 and an extrusion section 13 from front to back. The thread 2 is arranged on the feeding section 11 and the plasticizing section 12, and the outer diameter of the thread 2 remains unchanged equally from front to back. During the rotation of the screw 100, the material is positively conveyed on the screw 100 by the thread 2 and is melted and plasticized under the shearing of the thread 2.
[0027] Among them, the length L2 of the plasticizing section 12 is greater than the length L1 of the feeding section 11, the length L1 of the feeding section 11 is greater than the length L3 of the extrusion section 13, and the length L2 of the plasticizing section 12 is greater than 1 / 2 of the length L of the rod body 1. The ultra-long plasticizing section 12 can promote the full melting and plasticizing of the solid-phase material and improve the extrusion quality of the screw.
[0028] As Figure 1 、 2 、4 shown, in the feeding section 11, the helix angle φ1 of the rear half of the feeding section is greater than the helix angle φ1 of the front half of the feeding section. The increase in the helix angle φ1 makes the width of the trough formed by the thread 2 on the rod body 1 increase. At the same time, the bottom diameter d of the rod body 1 increases from front to back, so that the depth of the trough formed by the thread 2 in the feeding section 11 gradually becomes shallower from front to back. The trough in the front section of the feeding section 11 is deeper, which can increase the feeding amount of the screw 100. The trough in the rear section of the feeding section 11 gradually becomes shallower and wider, which can quickly compress the material, improve the positive conveying efficiency of the material, and increase the contact area between the material and the screw, so that the material is quickly preheated and the melting conversion efficiency is improved. In the embodiment of the present application, the helix angle φ1 is 17.7°-23°, and the thread 2 forms a thread lead suitable for material feeding with a suitable helix angle in the feeding section 11, so as to ensure the stability of feeding while increasing the feeding amount.
[0029] As Figure 1 、3 As shown in FIGS. 4, in the plasticizing section 12, a helically extending liquid phase groove 31 is formed on the thread 2. The liquid phase groove 31 divides the thread 2 into a main ridge 21 and a secondary ridge 22 that helically extend respectively. The rear end face of the main ridge 21 and the front end face of the secondary ridge 22 define the liquid phase groove 31, and the rear end face of the secondary ridge 22 and the front end face of the main ridge 21 define the solid phase groove 32.
[0030] The plasticizing section 12 includes a long separation section 121 and a short separation section 122 connected to the rear end of the long separation section 121. The length L of the long separation section 121 21 is greater than the length L of the short separation section 122 22 . The main ridge 21 and the secondary ridge 22 converge at the front end of the long separation section 121, the junction of the long separation section 121 and the short separation section 122, and the rear end of the short separation section 122 respectively, so that the volume of the liquid phase groove 31 gradually increases from front to back in the long separation section 121 and the short separation section 122 respectively; the volume of the solid phase groove 32 gradually decreases from front to back in the long separation section 121 and the short separation section 122 respectively.
[0031] In the long separation section 121, the helix angle φ2 of the main ridge 21 remains constant from front to back. The long separation section 121 includes a front half connected to the feeding section 11 and a rear half connected to the short separation section 122 in the axial direction of the rod body. In the front half of the long separation section 121, the helix angle φ3 of the secondary ridge 22 is equal to the helix angle φ2 of the main ridge 21, so that the widths of the solid phase groove 32 and the liquid phase groove 31 in the front half of the long separation section 121 remain constant from front to back. In the initial stage of solid-liquid conversion, the heating area of the solid phase material can be increased, the melting speed can be accelerated, and the solid-liquid conversion efficiency can be improved.
[0032] In the rear half of the long separation section 121, the helix angle φ3 of the secondary ridge 22 is greater than the helix angle φ2 of the main ridge 21, so that the width of the solid phase groove 32 in the rear half of the long separation section 121 gradually decreases from front to back, and the width of the liquid phase groove 31 gradually increases from front to back. The increase in the helix angle φ3 of the secondary ridge 22 leads to an increase in the lead of the secondary ridge 22, so that the liquid phase groove 31 obtains a larger screw groove space to accommodate the gradually increasing liquid phase material, and accelerates the forward conveying of the material, shortens the residence time of the material on the screw, and effectively controls the temperature rise of the screw. The volume changes of the liquid phase groove 31 and the solid phase groove 32 conform to the solid-liquid conversion law of the plasticizing section 12.
[0033] In the short separation segment 122, the helix angle φ3 of the secondary edge 22 is greater than the helix angle φ2 of the primary edge 21, and the helix angle φ3 of the secondary edge 22 in the short separation segment 122 is less than the helix angle φ2 of the primary edge 21 in the long separation segment 121, such that the width of the solid phase groove 32 in the short separation segment 122 gradually decreases from front to back, and the width of the liquid phase groove 31 gradually increases from front to back. When the material enters the short separation segment 122, it has basically melted into a liquid-phase material, and the short separation segment 122 further plasticizes the molten material to improve the plasticization effect.
[0034] In the embodiment of the present application, the helix angle φ3 is 26.8° - 32.5°, and the helix angle φ2 is 23° - 28°. Within the corresponding helix angle range of the primary edge 21 and the secondary edge 22, it can ensure the plasticization effect on the material while improving the conveying efficiency, and is particularly suitable for extrusion equipment in high-speed production.
[0035] As Figure 1 shown, the extrusion segment 13 includes a barrier segment 131 and a mixing segment 132 connected in sequence from front to back, and the length of the barrier segment 131 is greater than the length of the mixing segment 132.
[0036] As Figure 1 、 5 、6 shown, a plurality of intermediate grooves 41 spirally extending along the rod body are provided on the barrier segment 131. The plurality of intermediate grooves 41 are circumferentially spaced apart along the rod body. An inlet groove 42 and an outlet groove 43 distributed along the same axis are provided between two adjacent intermediate grooves 41. Both the inlet groove 42 and the outlet groove 43 are parallel to the intermediate groove 41. In the rotation direction of the screw, a protruding first barrier 44 is formed between each inlet groove 42 and the downstream intermediate groove 41, and a protruding second barrier 45 is formed between each outlet groove 43 and the upstream intermediate groove 41. The material enters the barrier segment 131 from each inlet groove 42. During the rotation of the screw 100, the material crosses the corresponding first barrier 44 from the inlet groove 42 and enters the downstream intermediate groove 41, then crosses the corresponding second barrier 45 from the intermediate groove 41 and enters the downstream outlet groove 43, and finally exits the barrier segment 131 from the outlet groove 43. The material undergoes high shear at the gaps between the two barriers and the barrel, is further plasticized, and the plasticization effect is improved, thereby improving the quality of the final pipe product and enabling the various properties of the pipe product to meet market requirements.
[0037] As Figure 1 、 7As shown in Fig. 8, there are several mixing groups 5 arranged at intervals from front to back on the mixing section 132. Each mixing group 5 includes several mixing protrusions 51 arranged in sequence along the circumferential direction of the rod body 1, and the mixing protrusions 51 of adjacent two mixing groups 5 are arranged alternately in the circumferential direction of the rod body 1. The staggered arrangement of the mixing protrusions 51 can better disperse the mixture flow, improve the melt quality, and can appropriately reduce the temperature of the melt to eliminate the negative impact of temperature fluctuations.
[0038] The above shows and describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited by the above embodiments. The above embodiments and the descriptions in the specification only illustrate the principles of the present application. Without departing from the spirit and scope of the present application, the present application will have various changes and improvements. The scope of protection required by the present application is defined by the appended claims, the specification and their equivalents.
Claims
1. A screw for efficient pipe production, comprising a rod body extending in the front-rear direction and a thread spirally extending from front to back along the rod body, characterized in that, The rod body successively includes a feeding section, a plasticizing section, and an extrusion section from front to back. The length of the plasticizing section is greater than that of the feeding section, the length of the feeding section is greater than that of the extrusion section, and the length of the plasticizing section is greater than 1 / 2 of the length of the rod body. The outer diameter of the thread is arranged unchanged in the feeding section and the plasticizing section. The helix angle of the thread increases from front to back in the feeding section, and the depth of the trough formed by the thread in the feeding section gradually becomes shallower from front to back. The thread in the plasticizing section is provided with a helically extending liquid phase trough, and the liquid phase trough separates the thread into a main ridge and a secondary ridge. The plasticizing section includes a long separation segment and a short separation segment successively connected from front to back. The length of the long separation segment is greater than that of the short separation segment. The main ridge and the secondary ridge converge at the front end of the long separation segment, the junction of the long separation segment and the short separation segment, and the rear end of the short separation segment. The volume of the liquid phase trough gradually increases from front to back in the long separation segment and the short separation segment respectively. The extrusion section includes a barrier segment and a kneading segment successively connected from front to back. A plurality of slots helically extending along the rod body are provided on the barrier segment. The kneading segment has a plurality of kneading groups arranged at intervals from front to back, and each kneading group includes a plurality of kneading protrusions arranged successively along the circumferential direction of the rod body.
2. The screw for efficient pipe production according to claim 1, characterized in that, The bottom diameter of the feeding section increases from front to back.
3. The screw for efficient pipe production according to claim 1, wherein The helix angle of the thread in the feeding section is 17.7°-23°.
4. The screw for efficient pipe production according to claim 1, wherein, The rear end face of the main ridge and the front end face of the secondary ridge define the liquid phase trough, and the rear end face of the secondary ridge and the front end face of the main ridge define the solid phase trough. The volume of the solid phase trough gradually decreases from front to back in the long separation segment and the short separation segment respectively.
5. The screw for efficient pipe production according to claim 4, characterized in that, The long separation segment includes a front half connected to the feeding section and a rear half connected to the short separation segment. In the front half of the long separation segment, the width of the solid phase trough and the width of the liquid phase trough remain equal and unchanged from front to back. In the rear half of the long separation segment, the width of the solid phase trough gradually decreases from front to back, and the width of the liquid phase trough gradually increases from front to back. In the short separation segment, the width of the solid phase trough gradually decreases from front to back, and the width of the liquid phase trough gradually increases from front to back.
6. The screw for efficient pipe production according to claim 5, wherein, In the long separation segment, the helix angle of the main ridge remains equal and unchanged from front to back. In the front half of the long separation segment, the helix angle of the secondary ridge is equal to that of the main ridge. In the rear half of the long separation segment, the helix angle of the secondary ridge is greater than that of the main ridge. In the short separation segment, the helix angle of the secondary ridge is greater than that of the main ridge, and the helix angle of the secondary ridge in the short separation segment is less than that of the main ridge in the long separation segment.
7. The screw for efficient pipe production according to claim 6, characterized in that, The helix angle of the secondary edge is 26.8° - 32.5°, and the helix angle of the primary edge is 23° - 28°.
8. The screw for efficient pipe production according to claim 1, wherein, The length of the barrier segment is greater than the length of the kneading segment.
9. The screw for efficient pipe production according to claim 1, characterized in that, The several notches include a plurality of intermediate notches circumferentially spaced along the rod body, a plurality of feed notches and a plurality of discharge notches parallel to the intermediate notches. The feed notches and the discharge notches distributed along the same center line are arranged between two adjacent intermediate notches. In the rotation direction of the screw, a protruding first barrier is formed between each feed notch and the downstream intermediate notch, and a protruding second barrier is formed between each discharge notch and the upstream intermediate notch.
10. The screw for efficient pipe production according to claim 1, characterized in that, The kneading protrusions of two adjacent kneading groups are alternately arranged circumferentially on the rod body.