High-density polyethylene silicon core pipe inner and outer layer fusion extrusion molding device

Abstract

The utility model relates to the technical field of silicon core pipe extrusion molding, in particular to a high-density polyethylene silicon core pipe inner and outer layer fusion extrusion molding device which comprises a mold body, and a flow guide hole for guiding hot melt materials is formed in the mold body; a drainage module is arranged on the flow guide hole; the drainage module comprises an elastic membrane and a fixing assembly; the elastic membrane is detachably connected into the mold body through the fixing assembly. The center of the elastic membrane is provided with a drainage opening for the hot melt to pass through, the drainage opening can expand along with the increase of the pressure of the hot melt and extend into the flow guide hole, and when the pressure of the hot melt disappears, the drainage opening shrinks and returns to the outside of the flow guide hole. Through the dynamic aperture adjusting function of the elastic membrane, self-cleaning and blockage prevention of the flow guide hole are achieved, and the production efficiency is improved.

Description

Technical Field

[0001] This utility model relates to the field of silicon core tube extrusion molding technology, specifically to a high-density polyethylene silicon core tube inner and outer layer fusion extrusion device. Background Technology

[0002] HDPE silicon core pipe is a novel composite pipe with a silicone solid lubricant on its inner wall. The main raw material is high-density polyethylene, and the core layer is a silicone solid lubricant with a low coefficient of friction. A patent with publication number CN213704446U discloses a multi-layer co-extrusion mold for silicon core pipe, employing a combination of an outer diversion mold and guide holes to achieve core material diversion. Specifically, the outer diversion mold has multiple radial guide holes circumferentially opened, and the hot melt material of the core layer enters the extrusion chamber B through these guide holes, then is extruded synchronously with the surface material extruded into the extrusion chamber A. However, this structure has the following drawbacks in practical applications:

[0003] 1. The guide hole is prone to clogging: The guide hole is a fixed radial through hole. After long-term use, hot melt material residue is prone to accumulate on the inner wall of the channel. Especially when processing high viscosity materials, the channel is prone to forming glue, resulting in uneven flow or even complete blockage, requiring frequent machine shutdowns for disassembly and cleaning.

[0004] 2. High maintenance cost: The guide hole is integrated inside the outer diversion mold body. During cleaning, the core components such as the mold sleeve and the outer diversion mold body need to be completely disassembled, which is complicated and can easily damage the precision mating surfaces, increasing maintenance time and cost.

[0005] 3. Insufficient adaptability: The diameter and arrangement of the flow guide holes are fixed, and the flow distribution parameters cannot be adjusted according to the differences in material flowability. This results in poor compatibility with materials of different viscosities and easily leads to quality problems such as poor interlayer bonding or uneven thickness.

[0006] Existing improvement solutions mostly delay clogging by optimizing the angle of the guide holes or surface polishing, but they fail to address the structural defects of fixed guide holes. Therefore, there is an urgent need for a guide structure that is quick to clean, easy to maintain, and highly adaptable to improve mold operation stability and production efficiency. Utility Model Content

[0007] In view of this, the purpose of this utility model is to provide a high-density polyethylene silicon core tube inner and outer layer fusion extrusion device, which realizes self-cleaning and anti-clogging of the guide hole through the dynamic pore size adjustment function of the elastic diaphragm, thereby improving production efficiency.

[0008] To achieve the above objectives, this utility model provides the following technical solution:

[0009] A high-density polyethylene silicon core tube inner and outer layer fusion extrusion device includes a mold body, the mold body having a guide hole for guiding hot melt material; a flow guiding module is provided on the guide hole; the flow guiding module includes an elastic diaphragm and a fixing component; the elastic diaphragm is detachably connected to the mold body through the fixing component; the elastic diaphragm has a flow port at its center for the hot melt material to pass through, the flow port can expand and extend into the guide hole as the pressure of the hot melt material increases, and when the pressure of the hot melt material disappears, the flow port contracts and retracts to the outside of the guide hole.

[0010] As a further improvement of this utility model, the elastic diaphragm is made of a high-temperature resistant elastic alloy.

[0011] As a further improvement of this utility model, the drainage port is funnel-shaped.

[0012] As a further improvement of this utility model, the edge of the elastic diaphragm is processed with wavy pleats.

[0013] As a further embodiment of this utility model: the fixing component includes a lower pressure ring and an upper pressure ring; the outer periphery of the lower pressure ring is fixedly connected to the mold body, the upper pressure ring is detachably connected to the lower pressure ring by bolts, and the elastic diaphragm is disposed between the upper pressure ring and the lower pressure ring.

[0014] As a further improvement of this utility model, a spring washer is added to the head of the bolt.

[0015] By adopting the above technical solution, this utility model will have the following beneficial effects:

[0016] This invention provides a high-density polyethylene silicon core tube inner and outer layer fusion extrusion device. Through the pressure-response deformation of an elastic diaphragm, the inlet dynamically expands or contracts with the pressure of the hot melt material, adaptively adjusting the flow cross-sectional area of ​​the guide hole to avoid blockage caused by changes in material viscosity or pressure fluctuations. When the machine stops, the inlet retracts outside the guide hole, and the elastic force of the diaphragm squeezes out residual material, automatically peeling off residue from the hole wall and reducing the frequency of manual cleaning. The inlet module is connected to the mold body via fixing components (upper pressure ring, lower pressure ring, and bolts), allowing for quick disassembly and maintenance, reducing equipment downtime due to guide hole blockage.

[0017] Compared with existing technologies, this invention achieves self-cleaning and anti-clogging of the guide hole through the dynamic aperture adjustment function of the elastic diaphragm, thereby improving production efficiency. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the structure of the high-density polyethylene silicon core tube inner and outer layer fusion extrusion device according to an embodiment of the present invention;

[0020] Figure 2 for Figure 1 A cross-sectional view of the drainage module described in the embodiment in the retracted state of the drainage port;

[0021] Figure 3 for Figure 1 A cross-sectional view of the drainage module described in the embodiment with the drainage port enlarged;

[0022] Figure 4 for Figure 1 A three-dimensional view of the drainage module described in the embodiment in the retracted state of the drainage port.

[0023] The correspondence between the labels and component names in the attached figures is as follows:

[0024] 1. Mold body; 11. Guide hole; 12. Outer flow distribution mold body; 13. Extrusion cavity A; 14. Extrusion cavity B; 2. Drainage module; 21. Elastic diaphragm; 211. Drainage port; 22. Fixing component; 221. Lower pressure ring; 222. Upper pressure ring; 223. Bolt; 224. Spring washer. Detailed Implementation

[0025] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of this invention. Therefore, the following description is to be considered exemplary in nature and not restrictive.

[0026] Please refer to Figure 1-4In one embodiment of the high-density polyethylene silicon core tube inner and outer layer fusion extrusion device provided by this utility model, the high-density polyethylene silicon core tube inner and outer layer fusion extrusion device includes a mold body 1, and the mold body 1 is provided with guide holes 11 for guiding hot melt material; the mold body 1 adopts a combination structure of an outer diversion mold body 12 and guide holes 11 to realize the diversion of core layer material. Specifically, the outer diversion mold body 12 has multiple radial guide holes 11 circumferentially opened. These guide holes 11 are respectively connected to the extrusion cavity A13 and the extrusion cavity B14. The core layer hot melt material enters the extrusion cavity B14 through the guide holes 11, and is then extruded and formed synchronously with the surface material extruded into the extrusion cavity A13; the above belongs to the conventional design of existing silicon core tube multilayer co-extrusion molds.

[0027] Importantly, the guide hole 11 is provided with a flow-guiding module 2; the flow-guiding module 2 includes an elastic diaphragm 21 and a fixing component 22; the elastic diaphragm 21 is detachably connected to the mold body 1 through the fixing component 22; specifically, the fixing component 22 includes a lower pressure ring 221 and an upper pressure ring 222; both the lower pressure ring 221 and the upper pressure ring 222 are annular steel rings, the ring width of the lower pressure ring 221 is larger than that of the upper pressure ring 222, and the mold body 1 is welded to the outer periphery of the lower pressure ring 221; the upper pressure ring 222 is coaxially arranged above the lower pressure ring 221, and the outer periphery of the upper pressure ring 222 is detachably and vertically locked to the lower pressure ring 221 by 6 sets of M8 bolts 223, and the head of the bolts 223 is equipped with a spring washer 224 to increase the preload. The elastic diaphragm 21 is disposed between the edge of the upper pressure ring 222 and the lower pressure ring 221, and is held by the upper pressure ring 222 and the lower pressure ring 221; the center of the elastic diaphragm 21 is provided with a funnel-shaped inlet 211, through which the hot melt material can enter the guide hole 11.

[0028] In this embodiment, when no glue is injected, the inlet 211 is in its initial state and the elastic diaphragm 21 is undeformed. When glue is injected, the hot melt material expands the inlet 211 under the pressure of glue injection and enters the guide hole 11. The inlet 211 expands and extends into the guide hole 11 as the pressure of the hot melt material increases. After the machine stops, the pressure of the hot melt material disappears, and the inlet 211 contracts and retracts to the outside of the guide hole 11 under the elastic restoring force of the elastic diaphragm 21, causing the residual hot melt material to fall off.

[0029] As a preferred embodiment, the elastic diaphragm 21 is made of a high-temperature resistant elastic alloy (such as Inconel 718), is circular, and has a thickness of 0.5-1.0 mm, and still maintains its elastic deformation capability under operating conditions of 200-300°C.

[0030] As a preferred embodiment, the edge of the elastic diaphragm 21 is processed with wavy pleats, the pleat depth is 0.3mm and the wavelength is 5mm. When the mold body 1 is heated and expands, the pleats unfold to absorb the linear expansion difference between the mold body 1 and the elastic diaphragm 21, preventing the elastic diaphragm 21 from cracking due to thermal stress.

[0031] The method of use or working principle of this utility model is as follows:

[0032] When the hot melt material is injected under the pressure of the inlet, the flow impacts the elastic diaphragm 21, causing it to radially expand and deform towards the guide orifice 11 under fluid pressure. The small end of the guide orifice 211 is stretched, and the orifice diameter expands, increasing the flow rate of the hot melt material, enhancing shear stress, and reducing material adhesion to the orifice wall. During the injection process, the deformation of the elastic diaphragm 21 is adjusted in real time with the pressure; that is, when the injection pressure increases, the orifice diameter further expands; when the pressure decreases, the orifice diameter contracts. This adaptive mechanism matches the flow rate with the orifice diameter, avoiding local overload or blockage caused by pressure fluctuations. After shutdown, the pressure of the hot melt material disappears, and the elastic diaphragm 21 retracts under its own elasticity, restoring the orifice diameter of the small end of the guide orifice 211 to its original state. When the orifice diameter contracts, the orifice wall exerts a squeezing and shearing effect on the residual material, causing the adhered material to detach from the orifice wall and be flushed out with the material flow during the next startup.

[0033] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A high-density polyethylene silicon core tube inner and outer layer fusion extrusion device, comprising a mold body (1), wherein the mold body (1) is provided with a guide hole (11) for guiding hot melt material; characterized in that, The guide hole (11) is provided with a flow-guiding module (2); the flow-guiding module (2) includes an elastic diaphragm (21) and a fixing component (22); the elastic diaphragm (21) is detachably connected to the mold body (1) through the fixing component (22); the center of the elastic diaphragm (21) is provided with a flow-guiding port (211) for the hot melt material to pass through, the flow-guiding port (211) can expand and extend into the guide hole (11) as the pressure of the hot melt material increases, and when the pressure of the hot melt material disappears, the flow-guiding port (211) contracts and retracts to the outside of the guide hole (11).

2. The high-density polyethylene silicon core tube inner and outer layer fusion extrusion device according to claim 1, characterized in that, The elastic diaphragm (21) is made of a high-temperature resistant elastic alloy.

3. The high-density polyethylene silicon core tube inner and outer layer fusion extrusion device according to claim 1, characterized in that, The drainage port (211) is funnel-shaped.

4. The high-density polyethylene silicon core tube inner and outer layer fusion extrusion device according to claim 1, characterized in that, The edges of the elastic diaphragm (21) are processed with wavy pleats.

5. The high-density polyethylene silicon core tube inner and outer layer fusion extrusion device according to claim 1, characterized in that, The fixing component (22) includes a lower pressure ring (221) and an upper pressure ring (222); the lower pressure ring (221) is fixedly connected to the mold body (1) on its outer periphery, and the upper pressure ring (222) is detachably connected to the lower pressure ring (221) by bolts (223); the elastic diaphragm (21) is disposed between the upper pressure ring (222) and the lower pressure ring (221).

6. The high-density polyethylene silicon core tube inner and outer layer fusion extrusion device according to claim 5, characterized in that, The head of the bolt (223) is fitted with a spring washer (224).

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