Pipe extrusion device with a plunger
By employing a non-coaxial extrusion head and plunger rod design and a detachable shaping column, the cost problem of producing pipes of different wall thicknesses in existing plunger extruders has been solved, achieving flexible production and efficient material uniformity, and improving the quality of pipe forming.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- TIANJIN MINGDE HVAC EQUIP CO LTD
- Filing Date
- 2025-07-17
- Publication Date
- 2026-06-09
AI Technical Summary
Existing plunger extruders typically only produce pipes of one wall thickness. Changing the machinery to produce pipes of different wall thicknesses increases production costs and causes uneven material flow within the die, affecting pipe quality.
The extrusion head and plunger design adopts a non-coaxial layout, combined with a detachable shaping column and threaded rod. The wall thickness can be adjusted by the threaded rod, and the material forms a spiral mixing flow in the die head, which improves uniformity.
It enables rapid adjustment of pipe wall thickness and diameter, reduces equipment procurement and maintenance costs, improves material uniformity and pipe forming accuracy, and reduces equipment modification time.
Smart Images
Figure CN224334980U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of pipe processing technology, specifically to a pipe plunger extrusion molding device. Background Technology
[0002] Cross-linked polyethylene (PE-Xa) pipes are industrial pipes made from high-density polyethylene XL-1800 supplied by LG Chem of South Korea. They are formed into a three-dimensional network structure through a peroxide cross-linking process. They are mainly used in building hot and cold water transportation, floor radiant heating, and central air conditioning systems. These pipes have high temperature resistance (up to 95℃), pressure resistance (working pressure ≤2.5MPa), and chemical corrosion resistance. They have a thermal conductivity of about 0.38W / (m·K), low fluid resistance, and a service life of more than 50 years.
[0003] PE-Xa pipes are typically manufactured using extruders, with plunger extruders being a commonly used forming method. However, existing plunger extruders usually only allow for forming pipes of one wall thickness per machine. When processing pipes of different wall thicknesses is required, other machines need to be replaced, leading to the need for processing plants to purchase machines of different specifications, thus increasing production costs. In addition, in traditional plunger extruders, the extrusion die and plunger rod are coaxially arranged, which may result in uneven material flow within the die. To address these issues, a plunger extrusion forming device for pipes is proposed. Utility Model Content
[0004] To solve the above-mentioned technical problems, this utility model provides a pipe plunger extrusion molding device, which solves the problem that the current PE-Xa pipe manufacturing process usually requires the use of an extruder for pipe forming, and the plunger extruder is a commonly used forming method. However, existing plunger extruders can usually only form pipes of one wall thickness per machine. When different wall thicknesses need to be processed, other machines need to be changed, which leads to the need for processing plants to purchase machines of different specifications, thereby increasing production costs. In addition, in traditional plunger extruders, the extrusion die and plunger rod are set coaxially, which may lead to uneven material flow in the die.
[0005] To achieve the above objectives, the technical solution adopted by this utility model is as follows: a pipe plunger extrusion molding device, comprising a support body, a plunger cavity opened at the lower part of the support body, a plunger rod slidably connected inside the plunger cavity, a hydraulic cylinder for pushing the plunger rod to move fixedly installed at the lower right side of the support body, an extrusion die head detachably connected to the left side of the support body, an extrusion head fixedly connected to the upper left side of the extrusion die head, the extrusion head and the extrusion mold head being hollow, a shaping column provided inside the extrusion head, a threaded rod fixedly connected to the middle right side of the shaping column, the threaded rod being threadedly connected to the inside of the left side of the support body, and a feeding assembly installed above the extrusion die head.
[0006] Preferably, a cooling ring is fixedly installed on the outside of the extrusion head, and a waste discharge port is opened at the bottom of the extrusion die.
[0007] Preferably, the extrusion head and the shaping column are arranged on the same axis, and the diameter of the shaping column is smaller than the inner diameter of the extrusion head.
[0008] Preferably, the feeding assembly includes a pusher cylinder, which is fixedly connected to the upper center of the extrusion die head, and a mounting plate is fixedly connected to the upper part of the pusher cylinder.
[0009] Preferably, a rotating rod is rotatably connected to the upper left side of the mounting plate via a rotating shaft, and a pushing blade is fixedly connected to the lower end of the rotating rod inside the pushing cylinder.
[0010] Preferably, the upper end of the rotating rod passes through the mounting plate and is fixedly connected to a first gear, a servo motor is fixedly installed on the lower right side of the mounting plate, and the output end of the servo motor passes through the bottom surface of the mounting plate and is fixedly connected to a second gear, with the first gear meshing with the second gear.
[0011] Preferably, an inclined injection pipe is fixedly connected to the upper left side of the pusher cylinder, and an electromagnetic heating coil is fixedly installed on the lower outer side of the pusher cylinder.
[0012] Compared with the prior art, the advantages of this utility model are:
[0013] 1. This utility model incorporates a shaping column and a threaded rod. The shaping column is installed inside the extrusion head via the threaded rod. When producing pipes of different wall thicknesses, simply replacing the shaping column allows for quick adjustment of the pipe's wall thickness and diameter. This enables the production line to easily switch between different specifications of products. This design makes the production process more flexible and allows for rapid adjustments based on market demand, reducing the time and cost of equipment modification. By using shaping columns of different specifications without replacing the entire extrusion head or extruder, the investment cost of equipment in the production process can be greatly reduced. This modular design allows companies to produce different types of pipes using the same equipment, thereby saving on equipment procurement and maintenance costs.
[0014] 2. This utility model achieves an axially offset arrangement between the extruder head and the plunger rod, resulting in an eccentric material flow path. The radial shear force generated during plunger rod extrusion breaks the symmetrical flow field, forcing the material to form a spiral mixed flow at the die inlet, reducing dead zone volume and improving material uniformity. In the eccentric arrangement, the plunger rod extrusion direction and the die outlet direction form an eccentricity, changing the pressure transmission path to "oblique extrusion + radial flow." The pulse pressure is weakened by the buffering effect of the radial flow, reducing the extrusion swelling effect and improving the accuracy at the outlet. Attached Figure Description
[0015] Figure 1 This is a schematic diagram of the structure of this utility model;
[0016] Figure 2 This is a top view of the present invention;
[0017] Figure 3 for Figure 2 Sectional view at point AA;
[0018] Figure 4 for Figure 3 A magnified view of a portion of point P in the middle.
[0019] The numbers on the map are:
[0020] 1. Support body; 2. Plunger cavity; 3. Plunger rod; 4. Hydraulic cylinder; 5. Extrusion die head; 6. Waste discharge port; 7. Extrusion head; 8. Shaping column; 9. Threaded rod; 10. Cooling ring; 11. Feeding assembly; 1101. Pusher cylinder; 1102. Injection pipe; 1103. Electromagnetic heating coil; 1104. Rotating rod; 1105. Pushing blade; 1106. First gear; 1107. Mounting plate; 1108. Servo motor; 1109. Second gear. Detailed Implementation
[0021] In the description of this utility model, it should be noted that the terms "front", "up", "down", "left", "right", "vertical", "horizontal", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.
[0022] The following description is intended to disclose the present invention so that those skilled in the art can implement it. The preferred embodiments described below are merely examples, and other obvious variations will occur to those skilled in the art.
[0023] Reference Figures 1-4As shown, a pipe plunger extrusion molding device includes a support body 1, with a plunger cavity 2 formed at the lower part of the support body 1. A plunger rod 3 is slidably connected inside the plunger cavity 2. A hydraulic cylinder 4 for pushing the plunger rod 3 is fixedly installed on the lower right side of the support body 1. The hydraulic cylinder 4 has a working pressure range of 8-25MPa and a stroke of 500mm to ensure the extrusion requirements of pipes of different specifications. The hydraulic cylinder 4 is equipped with a pressure sensor and a displacement sensor, which can monitor the working pressure and the movement position of the plunger rod 3 in real time and feed the data back to the control system to achieve precise control of the extrusion process. An extrusion die 5 is detachably connected to the left side of the support body 1. An extrusion head 7 is fixedly connected to the upper left side of the extrusion die 5. The extrusion head 7 and the extrusion die 5 are hollow. A shaping column 8 is set inside the extrusion head 7. A threaded rod is fixedly connected to the middle right side of the shaping column 8. 9. The threaded rod 9 is threadedly connected to the inside of the left side of the support body 1. The feeding assembly 11 is installed above the extrusion die head 5. The support body 1 is made of high-strength alloy material and undergoes a special heat treatment process to give it sufficient strength and rigidity to withstand the huge reaction force generated by the hydraulic cylinder 4 during operation and the pressure generated by the molten raw material during extrusion. This avoids affecting the extrusion quality of the pipe due to the deformation of the support body 1. At the same time, the internal structure of the support body 1 is reasonably designed, the piston cavity 2 has high machining precision, and the fitting clearance between it and the piston rod 3 is moderate. This ensures that the piston rod 3 can slide smoothly and effectively prevents the leakage of molten raw material. The head design of the piston rod 3 matches the shape of the piston cavity 2, which can better contact the molten raw material, improve the uniformity of pressure transmission, and avoid the situation of excessive or insufficient local pressure, thereby ensuring the stable quality of the pipe.
[0024] Specifically, a cooling ring 10 is fixedly installed on the outside of the extruder head 7, and a waste discharge port 6 is opened at the bottom of the extrusion die head 5. The cooling ring 10 can be understood as a hollow annular tube with flowing cold water inside. The flowing cold water cools the extruder head 7 and the tube. The specific principle can be referred to as the CPU water cooler in a computer. A sealing plug is installed inside the waste discharge port 6 to prevent the molten raw material from flowing out during tube forming. When it is necessary to discharge waste, the sealing plug is opened and the waste can flow out automatically.
[0025] Specifically, the extrusion head 7 and the shaping column 8 are arranged on the same axis, and the diameter of the shaping column 8 is smaller than the inner diameter of the extrusion head 7. This design allows the molten raw material to be uniformly extruded from the gap between the shaping column 8 and the extrusion head 7 during the extrusion process, forming a hollow tube with uniform wall thickness. Furthermore, by replacing the shaping column 8 with different diameters, tubes with different wall thicknesses can be easily produced, improving the versatility of the device. The extrusion head 7 and the shaping column 8 are made of high-hardness, high-wear-resistant alloy materials, and undergo precision machining and surface treatment to ensure dimensional accuracy and surface finish, thereby improving the forming quality of the tube. In addition, the shaping column 8 is connected to the internal thread on the left side of the support body 1 via a threaded rod 9. This connection method is robust and reliable, facilitating disassembly and installation, and allowing for quick and accurate positioning when replacing the shaping column 8, reducing production preparation time.
[0026] Specifically, the feeding assembly 11 includes a pusher cylinder 1101, which is fixedly connected to the upper middle part of the extrusion die 5. An mounting plate 1107 is fixedly connected above the pusher cylinder 1101. The pusher cylinder 1101 provides space for the storage and transportation of molten raw materials. Its fixed connection to the upper middle part of the extrusion die 5 enables the raw materials to smoothly enter the extrusion die 5, ensuring the continuity of feeding.
[0027] Specifically, a rotating rod 1104 is rotatably connected to the upper left side of the mounting plate 1107 via a rotating shaft. The lower end of the rotating rod 1104 is fixedly connected to a pusher blade 1105 inside the pusher cylinder 1101. The pusher blade 1105 is spiral in shape and can push the molten raw material into the extrusion die head 5 when rotating. The spiral angle and pitch of the pusher blade 1105 are designed according to the characteristics of the raw material and production requirements to adjust the conveying speed and mixing effect of the raw material.
[0028] Specifically, the upper end of the rotating rod 1104 passes through the mounting plate 1107 and is fixedly connected to the first gear 1106. A servo motor 1108 is fixedly installed on the lower right side of the mounting plate 1107. The output end of the servo motor 1108 passes through the bottom surface of the mounting plate 1107 and is fixedly connected to the second gear 1109. The first gear 1106 meshes with the second gear 1109. The servo motor 1108 drives the second gear 1109 to rotate, which in turn drives the rotating rod 1104 to rotate, thereby realizing the automatic rotation of the blade 1105 and improving the automation level of feeding.
[0029] Specifically, an inclined injection pipe 1102 is fixedly connected to the upper left side of the pusher cylinder 1101, and an electromagnetic heating coil 1103 is fixedly installed on the lower outer side of the pusher cylinder 1101. A filter device (not shown) is installed at the inlet of the injection pipe 1102, which can filter out impurities in the raw materials and prevent impurities from entering the pusher cylinder 1101 and affecting the quality of the pipe. The electromagnetic heating coil 1103 adopts advanced electromagnetic induction heating technology, which has the advantages of fast heating speed, high thermal efficiency and precise temperature control.
[0030] Working principle: Raw materials are poured into the pusher cylinder 1101 through the inclined injection pipe 1102. The electromagnetic heating coil 1103 heats the pusher cylinder 1101 to 200-220℃ (the melting temperature of PE-Xa raw materials). The servo motor 1108 drives the second gear 1109 to rotate, which in turn drives the rotating rod 1104 to rotate through the meshing first gear 1106. The spiral-shaped pusher blade 1105 evenly stirs the raw materials and pushes them to the extrusion die head 5. The rotation speed of the pusher blade 1105 is automatically adjusted according to the viscosity of the raw materials: when the viscosity of the raw materials is high, the rotation speed is increased to 300 r / min to enhance shear plasticization; when the viscosity is low, the speed is reduced to 100 r / min to avoid overheating and decomposition. The electromagnetic heating coil 1103 has a three-stage temperature control: the feeding section is 200℃. The plasticizing section is 210℃ and the discharge section is 220℃ to ensure that the raw material is fully melted. The hydraulic cylinder 4 pushes the plunger rod 3 to move to the left in the plunger cavity 2, applying a pressure of 10-20MPa to the molten raw material. The raw material enters the extrusion head 7 through the extrusion die 5 and is extruded from the gap between the shaping column 8 and the extrusion head 7, thus forming a hollow tube. The cooling ring 10 on the outside of the extrusion head 7 is circulated with cold water, which cools and solidifies the tube as it passes through. The water temperature at the outlet of the cooling ring 10 is controlled at 35-40℃ to ensure that the surface temperature of the tube drops below 50℃, avoiding deformation during subsequent handling. When producing tubes with different wall thicknesses, simply unscrew the shaping column 8 and the threaded rod 9 from the left side of the support body 1 and replace the shaping column 8 with one of the corresponding diameter.
[0031] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model. The scope of protection of this utility model is defined by the appended claims and their equivalents.
Claims
1. A plunger-type extrusion molding device for pipes, characterized in that: The system includes a support body (1), a plunger cavity (2) is provided in the lower part of the support body (1), a plunger rod (3) is slidably connected in the plunger cavity (2), a hydraulic cylinder (4) for pushing the plunger rod (3) is fixedly installed on the lower right side of the support body (1), an extrusion die (5) is detachably connected to the left side of the support body (1), an extrusion head (7) is fixedly connected to the upper left side of the extrusion die (5), the extrusion head (7) and the extrusion die (5) are hollow, a shaping column (8) is provided inside the extrusion head (7), a threaded rod (9) is fixedly connected to the middle right side of the shaping column (8), the threaded rod (9) is threadedly connected to the inside of the left side of the support body (1), and a feeding assembly (11) is installed above the extrusion die (5).
2. The pipe plunger extrusion molding apparatus according to claim 1, characterized in that: A cooling ring (10) is fixedly installed on the outside of the extrusion head (7), and a waste discharge port (6) is opened at the bottom of the extrusion die (5).
3. The pipe plunger extrusion molding apparatus according to claim 1, characterized in that: The extrusion head (7) and the shaping column (8) are arranged on the same axis, and the diameter of the shaping column (8) is smaller than the inner diameter of the extrusion head (7).
4. A pipe plunger extrusion molding apparatus according to any one of claims 1-3, characterized in that: The feeding assembly (11) includes a pusher cylinder (1101), which is fixedly connected to the middle part above the extrusion die (5), and an mounting plate (1107) is fixedly connected above the pusher cylinder (1101).
5. The pipe plunger extrusion molding apparatus according to claim 4, characterized in that: A rotating rod (1104) is rotatably connected to the upper left side of the mounting plate (1107) via a rotating shaft. The lower end of the rotating rod (1104) is fixedly connected to a pushing blade (1105) inside the pusher cylinder (1101).
6. The pipe plunger extrusion molding apparatus according to claim 5, characterized in that: The upper end of the rotating rod (1104) passes through the mounting plate (1107) and is fixedly connected to the first gear (1106). A servo motor (1108) is fixedly installed on the lower right side of the mounting plate (1107). The output end of the servo motor (1108) passes through the bottom surface of the mounting plate (1107) and is fixedly connected to the second gear (1109). The first gear (1106) meshes with the second gear (1109).
7. The pipe plunger extrusion molding apparatus according to claim 4, characterized in that: An inclined injection pipe (1102) is fixedly connected to the upper left side of the pusher cylinder (1101), and an electromagnetic heating coil (1103) is fixedly installed on the lower outer side of the pusher cylinder (1101).