Spiral Die and Pipe Composite Equipment with the Same

Abstract

The present invention relates to the field of composite pipe manufacturing equipment, and discloses a spiral die and a pipe composite equipment having the same. The spiral die includes a spiral die assembly (20) formed with a plurality of spiral flow channels (21) and a flow splitting assembly (30) including at least a first flow splitting ring (31). The flow splitting assembly (30) is arranged at the feeding end of the spiral die assembly (20). The first flow splitting ring (31) is provided with a first arc-shaped flow channel (311) extending in the circumferential direction and a first material through hole (312) axially penetrating and extending from both ends of the first arc-shaped flow channel (311), and can split and convey the material flow to the corresponding plurality of spiral flow channels (21) through the first material through hole (312). The spiral die of the present invention can convert the feeding pressure into axial pressure when the material flow enters the spiral die assembly, and at the same time realize the uniform distribution of the composite material in the circumferential direction, effectively avoid the radial offset of the spiral flow channel, and extrude a composite layer with a uniform wall thickness.

Description

Technical Field

[0001] The present invention relates to composite pipe manufacturing equipment, and particularly to a spiral die. On this basis, the present invention further relates to a pipe composite equipment having the spiral die. Background Art

[0002] In the manufacture of composite pipes, it is usually necessary to form a plastic outer layer by compounding molten plastic on the outer peripheral surface of the pipe through a plastic extrusion die. For example, in the manufacturing process of a steel wire mesh reinforced composite plastic pipe, a spiral die can be used to form a PE outer layer on the outer peripheral surface of the pipe to be compounded. Among them, since the pipe to be compounded needs to run forward along the central axis of the spiral die during the compounding process, a side feeding method is usually adopted to feed the composite material.

[0003] As Figure 1 shown is a schematic cross-sectional structure diagram of a typical spiral die. Among them, molten plastic can be fed into the die through a radial feed port 313, and passes through one or more spiral channels 21 formed by a die shell 22 and a spiral die core 23 of a spiral die assembly 20, so that the molten plastic fills the periphery of the spiral die core 23, and then is extruded from an annular material extrusion channel in a die head assembly 10 as an outer layer material surrounding the pipe to be compounded and laid on the outer peripheral surface of the pipe. During this process, air between the extruded outer layer material and the pipe to be compounded can be sucked through a suction hole on the spiral die assembly 20, so that the outer layer material is tightly adhered to the pipe running forward (in the direction from right to left in the figure), and the compounding of the outer layer material is completed.

[0004] However, in the above compounding process, the molten plastic is directly injected into the spiral channel 21 of the spiral die assembly 20 from the radial feed port 313. The spiral channel 21 is a narrow cavity with a small flow cross-section formed on the outer peripheral surface of the spiral die core 23, making it difficult for the molten plastic to be evenly distributed over the entire circumference. As a result, the thickness of the plastic outer layer extruded from the annular material extrusion channel of the die head assembly 10 is uneven, and it is difficult to eliminate the foregoing influence by adjusting the die head assembly 10, which is particularly obvious for large-scale dies for large pipe diameters or thick composite layers.

[0005] Among them, in order to enable the molten plastic to pass through and fill the spiral channel 21, a relatively high pressure needs to be applied to the molten plastic fed in from the feed side, which causes the spiral die core 23 whose radial relative position is fixed by a rear pressure ring 34 to directly bear a relatively high radial feed pressure at the feed end. This not only makes the spiral die core 23 prone to radial offset relative to the die shell 22, exacerbating the problem of uneven composite layer thickness, but may even cause material leakage or damage to the connecting bolts connecting the rear pressure ring 34 due to excessive shear force. Summary of the Invention

[0006] The purpose of the present invention is to overcome the problem in the prior art that the spiral die is difficult to ensure the uniformity of the wall thickness of the composite layer, and to provide a spiral die that can effectively reduce the influence of the feed end pressure on the uniformity of the wall thickness of the extruded composite layer.

[0007] In order to achieve the above-mentioned objectives, the present invention provides a spiral mold, including: a spiral mold assembly, which is formed with a plurality of spirally extending spiral flow channels; a diverter assembly, which is arranged at the feed end of the spiral mold assembly and includes a first diverter ring, which is provided with a first arc flow channel extending circumferentially and connecting the plurality of spiral flow channels.

[0008] Preferably, the first diverter ring is formed with first material through holes extending axially from both ends of the first arc-shaped flow channel, so that the material flow can be diverted and conveyed to a plurality of corresponding spiral flow channels through the first material through holes.

[0009] Preferably, the first diverter ring is provided with a radial feed port connected to the first arc-shaped flow channel.

[0010] Preferably, a rear pressure ring is connected to one end of the diverter assembly facing away from the spiral mold assembly, the first arc-shaped flow channel is formed on the side of the first diverter ring facing the rear pressure ring, and the rear pressure ring is connected to seal the first arc-shaped flow channel on the surface opposite to the first diverter ring.

[0011] Preferably, the surface of the rear pressure ring on one side facing the first diverter ring has a finish surface, and the first diverter ring is provided with sealing ring surfaces respectively located radially inside and outside the first arc-shaped flow channel, and the rear pressure ring is connected so that the sealing ring surface and the finish surface fit each other to seal the first arc-shaped flow channel.

[0012] Preferably, the rear pressure ring and the first diverter ring are axially clamped and fixed by a plurality of inner ring clamping bolts respectively located on the radial inner side of the first arc-shaped flow channel and a plurality of outer ring clamping bolts respectively located on the radial outer side, and / or, a plurality of positioning pin holes are respectively formed on the first diverter ring and the rear pressure ring.

[0013] Preferably, the diverter assembly includes a second diverter ring stacked on the side of the first diverter ring facing the spiral mold assembly, the second diverter ring is provided with a plurality of second arc flow channels distributed along the circumferential direction and second material through holes extending axially through both ends of the second arc flow channels, and the first material through holes correspond to the middle position of the corresponding second arc flow channels, so that the material flow can be diverted and conveyed to a plurality of corresponding spiral flow channels through the first material through holes, the second arc flow channels and the second material through holes in sequence.

[0014] Preferably, the second arc-shaped flow channel is formed on one end face of the second flow dividing ring facing the first flow dividing ring, and the first flow dividing ring and the second flow dividing ring are connected to seal the second arc-shaped flow channel on their opposite surfaces.

[0015] Preferably, one end of the flow dividing assembly adjacent to the spiral die assembly has a communication ring, which is connected to the spiral die assembly and is formed with a third material through hole for communicating the first material through hole with a plurality of the spiral flow channels.

[0016] Preferably, the spiral die assembly includes: a die shell, in which a die cavity is formed; a spiral die core, which is arranged in the die cavity and forms the spiral flow channel spirally extending around the spiral die core between the spiral die core and the die shell, and / or, one end of the spiral die assembly far from the flow dividing assembly is connected with a die head assembly, which includes a core die and a die orifice arranged around the core die, and a material extrusion channel communicating the spiral flow channel is formed between the die orifice and the core die, and / or, the spiral die has a heating assembly, which is arranged to at least surround the spiral die assembly and the flow dividing assembly.

[0017] Preferably, one end of the flow dividing assembly far from the spiral die assembly is connected with a vacuum pumping assembly, which is arranged to allow the pipe to be compounded to pass through along the central axis, and a plurality of suction holes are arranged on the peripheral surface of the vacuum pumping assembly.

[0018] In a second aspect of the present invention, a pipe compounding device is provided, which includes the above-mentioned spiral die to be able to form a plastic outer layer on the outer peripheral surface of the pipe to be compounded.

[0019] Through the above technical solution, in the spiral die of the present invention, the molten plastic is divided and conveyed to the spiral flow channels of the spiral die assembly through the flow dividing assembly, so that the feeding pressure is applied to the first flow dividing ring of the flow dividing assembly through the first arc-shaped flow channel extending in the circumferential direction. Therefore, it can withstand a very large feeding pressure, and the feeding pressure can be converted into an axial pressure when the material flows into the spiral die assembly, and at the same time, the composite material is evenly distributed in the circumferential direction, which can effectively avoid the radial offset of the spiral flow channel or the excessive shear action on the connecting bolts, and extrude a composite layer with a uniform wall thickness. Description of the Drawings

[0020] Figure 1 is a schematic cross-sectional structure view of a spiral die in the prior art;

[0021] Figure 2 is a schematic cross-sectional structure view of a spiral die according to a preferred embodiment of the present invention;

[0022] Figure 3Schematic cross-sectional structure diagram of a spiral die according to another preferred embodiment of the present invention;

[0023] Figure 4 is Figure 3 External structure view of the spiral die in the working state in;

[0024] Figure 5 is Figure 3 Exploded view of some components in the flow splitting assembly of the spiral die in;

[0025] Figure 6 is Figure 2 or Figure 3 Schematic cross-sectional structure diagram of the first flow splitting ring of the spiral die in.

[0026] Explanation of reference numerals

[0027] 10 - Die head assembly; 11 - Core die; 12 - Die orifice; 13 - Material extrusion channel; 14 - Die head compression ring;

[0028] 20 - Spiral die assembly; 21 - Spiral flow channel; 22 - Die shell; 23 - Spiral die core;

[0029] 30 - Flow splitting assembly; 31 - First flow splitting ring; 311 - First arc-shaped flow channel; 312 - First material through hole; 313 - Radial feed port; 32 - Second flow splitting ring; 321 - Second arc-shaped flow channel; 322 - Second material through hole; 33 - Connecting ring; 331 - Third material through hole; 34 - Rear compression ring; 35 - Inner ring compression bolt; 36 - Outer ring compression bolt; 37 - Sealing ring surface; 38 - Positioning pin hole;

[0030] 40 - Vacuum pumping assembly; 41 - Suction hole; 42 - Sealing element;

[0031] 50 - Heating assembly;

[0032] 100 - Pipe to be laminated. Detailed description of the specific embodiments

[0033] The following further elaborates on the specific embodiments of the present invention with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the present invention.

[0034] In the present invention, unless otherwise specified, the orientation terms such as "upper, lower, left, right" generally refer to the upper, lower, left, and right as shown in the reference drawings; "inner, outer" refer to the inner and outer of the contour of each component itself.

[0035] Refer to Figures 2 to 6As shown, a first aspect of the present invention provides a spiral die, which includes a spiral die assembly 20 and a flow splitting assembly 30. Multiple spiral extending spiral channels 21 are formed in the spiral die assembly 20; the flow splitting assembly 30 is arranged at the feeding end of the spiral die assembly 20 and at least includes a first flow splitting ring 31. The first flow splitting ring 31 can divide the composite material (such as molten plastic) introduced through a radial feeding port 313 into multiple strands, and then shunt and convey them to multiple corresponding spiral channels 21. Then, after passing through the spiral channels 21, it is covered on the outer peripheral surface of the pipe 100 to be compounded running forward to form an outer pipe layer.

[0036] Among them, referring to Figure 5 and Figure 6 the first flow splitting ring 31 shown therein, it is arranged corresponding to the spiral die assembly 20 as an annular shape allowing the pipe 100 to be compounded to pass through, and is provided with a first arc-shaped channel 311 extending in the circumferential direction and first material through holes 312 axially penetrating and extending from both ends of the first arc-shaped channel 311 to shunt and convey the material flow through the first material through holes.

[0037] In this case, the spiral die of the present invention can apply the feeding pressure to the first flow splitting ring 31 of the flow splitting assembly 30 through the first arc-shaped channel 311 extending in the circumferential direction. The first flow splitting ring 31 can be a steel structure part, thus being able to withstand a very large feeding pressure, and can convert the feeding pressure into an axial pressure through the first material through holes 312 extending in the axial direction. At the same time, it realizes the uniform distribution of the composite material in the circumferential direction, can effectively avoid the radial offset of the spiral channels 21 or the excessive shear action on the connecting bolts (such as those used to connect the rear pressure plate 34), and extrude a composite layer with a uniform wall thickness.

[0038] In Figure 5 the first flow splitting ring 31 shown therein, the first arc-shaped channel 311 thereon has an approximately semi-circular extension length, thus being able to divide a stream of material introduced through a radial feeding port 313 into two streams of material located at the radial two ends of the first flow splitting ring 31 through the first material through holes 312 located at both ends of the first arc-shaped channel 311. In this way, the material flow can be more evenly distributed in the circumferential direction, facilitating the uniform application of the material flow pressure on relevant components, avoiding radial offset, and being beneficial to extruding a composite layer with a uniform wall thickness and improving product quality.

[0039] The following will further illustrate the preferred solutions of the present invention in combination with different preferred embodiments shown in the drawings. Among them, Figure 5 the first flow splitting ring 31 in the shown flow splitting assembly and Figure 6 the first flow splitting ring 31 shown therein can have the same structure and can be applicable to Figure 2 the spiral die shown therein; at the same time, the Figure 5 flow splitting assembly in it and Figure 6The first flow splitting ring in [the above] can also be used in Figure 3 the spiral die of another preferred embodiment shown in

[0040] Referring to Figure 2 shown in [the figure], a spiral die according to a preferred embodiment of the present invention includes a die head assembly 10, a spiral die assembly 20, a flow splitting assembly 30, etc. connected in sequence. Among them, the spiral die assembly 20 may include a die shell 22 or a spiral die core 23. A die cavity is formed inside the die shell 22; a spiral flow channel 21 may be formed on the outer peripheral surface of the spiral die core 23, and the spiral die core 23 is arranged in the die cavity of the die shell 22 to enclose the spiral flow channel 21 on the circumferential surface.

[0041] The discharge end (left end shown in the figure) of the spiral die assembly 20 is connected to the die head assembly 10. The die head assembly 10 includes a core die 11 and a die orifice 12. The core die 11 is arranged inside the die orifice 12 and a material extrusion channel 13 is formed between the outer peripheral surface of the core die 11 and the inner peripheral surface of the die orifice 12. The die head assembly 10 can be axially press-connected to the discharge end of the spiral die assembly 20 through a die head compression ring 14 and connected so that the material extrusion channel 13 communicates with the spiral flow channel 21 of the spiral die assembly 20. In some alternative embodiments, the die head assembly can be integrally arranged on the spiral die assembly 20, and the molten plastic conveyed by the spiral flow channel 21 is coated on the outer peripheral surface of the pipe through a radially shrinking material extrusion channel 13.

[0042] In order to keep the composite material in a molten state during the extrusion process, the spiral die may be provided with a heating assembly 50. The heating assembly 50 is arranged to surround the above-mentioned die head assembly 10, spiral die assembly 20, and the subsequent flow splitting assembly 30 (including the radial feed port 313), etc., so as to keep an appropriate temperature during the flow of the composite material in the spiral die.

[0043] The flow splitting assembly 30 of the spiral die includes a first flow splitting ring 31. The first flow splitting ring 31 has a first arc-shaped flow channel 311 extending in the circumferential direction and a first material through hole 312 extending axially through (combined with Figure 5 and Figure 6 shown in [the figure]), and is provided with a radial feed port 313 communicating with its first arc-shaped flow channel 311. Thus, molten material can be introduced from the side of the spiral die, which is convenient for the arrangement of the feeding device. For this purpose, a radial insertion port communicating with the first arc-shaped flow channel 311 can be formed on the first flow splitting ring 31, and the feed pipe can be inserted into the first flow splitting ring 31 to introduce molten material into the first arc-shaped flow channel 311. It should be understood that in other embodiments, the feed port can also be arranged at other appropriate positions or directions. For example, the feed pipe can be inserted into the first flow splitting ring 31 in a direction with a certain inclination angle relative to the radial direction.

[0044] After injecting molten material into the first arc-shaped flow channel 311 through the above-mentioned radial feed port 313, the molten material has a relatively large feed pressure, and then flows circumferentially in the first arc-shaped flow channel 311, and flows through the first material through holes 312 at both ends of the first arc-shaped flow channel 311 to the side (the left side in the figure) of the first diversion ring 31 facing the spiral die 20, and then enters the spiral flow channel 21 of the spiral die assembly 20, and is extruded through the material extrusion channel 13 of the die head assembly 10 and coated on the outer peripheral surface of the pipe to be compounded. During this process, the first diversion ring 31 not only converts the radial feed pressure into an axial pressure to prevent the spiral die core 23 from radially shifting in the die shell 22, but also enables the molten material to be circumferentially evenly distributed through the diversion effect of the first arc-shaped flow channel 311 and the first material through holes 312, which is beneficial to extruding a composite layer with uniform wall thickness.

[0045] Continue to refer to Figure 2 、 Figure 5 and Figure 6 As shown, the first arc-shaped flow channel 311 can be formed on the surface of the first diversion ring 31 facing away from the spiral die assembly 20, and a rear pressure ring 34 is connected to this side, that is, the rear pressure ring 34 is connected to the side of the first diversion ring 31 where the first arc-shaped flow channel 311 is formed. Moreover, the rear pressure ring 34 is connected to seal the first arc-shaped flow channel 311 on the surface opposite to the first diversion ring 31. Thus, the first arc-shaped flow channel 311 can be easily formed on the first diversion ring 31, and the rear pressure ring 34 can be used as the installation base for related accessory parts. In other embodiments, the first arc-shaped flow channel 311 can be formed on the side of the first diversion ring 31 facing the spiral die assembly 20. Thus, there is no need for the aforementioned rear pressure ring to seal the first arc-shaped flow channel 311, and there is no need to form the first material through holes 312 on the first diversion ring 31. Instead, a communication ring 33 as shown in Figure 5 is provided between the first diversion ring 31 and the spiral die assembly 20 to communicate with the spiral flow channel 21 through an axial through hole (i.e., the third material through hole 331 shown in the figure) formed at an appropriate position of the communication ring 33. Additionally, in other alternative embodiments, the first diversion ring 31 can also be formed by docking two components that face each other and have flow channel grooves formed on their opposite surfaces respectively to form the first arc-shaped flow channel. By arranging the first arc-shaped flow channel 311 on the side surface of the first diversion ring 31, the extremely high requirement for dimensional consistency in the docking of the flow channel grooves can be avoided.

[0046] In order to connect the rear compression ring 34 and the first flow dividing ring 31 so as to seal the first arc-shaped flow channel 311 on their opposite surfaces, a high-temperature resistant sealing gasket can be clamped and installed between them, or an engaging concave-convex structure can be provided on their opposite surfaces, etc. In the illustrated preferred embodiment, sealing ring surfaces 37 are formed on one surface of the first flow dividing ring 31 facing the rear compression ring 34, respectively located on the radially inner side and the radially outer side of the first arc-shaped flow channel 311. One surface of the rear compression ring 34 facing the first flow dividing ring 31 has a finish-machined surface, which can be fitted with the sealing ring surface 37 of the first flow dividing ring 31 to seal the first arc-shaped flow channel 311 accordingly. For this purpose, finish machining can be performed only on an appropriate area of the rear compression ring 34 corresponding to the first arc-shaped flow channel 311, and by applying an axial force towards each other on the rear compression ring 34 and the first flow dividing ring 31, the first arc-shaped flow channel 311 can be effectively sealed. Moreover, by providing the sealing ring surface 37 with a smaller radial width, the axial force can correct the inevitable deformation or dimensional error during machining, ensure that the first arc-shaped flow channel 311 is completely sealed, prevent material leakage, and avoid high machining costs.

[0047] For this purpose, fasteners such as bolts can also be used to axially tension the rear compression ring 34 and the first flow dividing ring 31. Specifically, multiple inner ring clamping bolts 35 evenly distributed in the circumferential direction can be provided on the radially inner side of the first arc-shaped flow channel 311; multiple outer ring clamping bolts 36 evenly distributed in the circumferential direction can be provided on the radially outer side of the first arc-shaped flow channel 311, thereby providing sufficient axial force to axially clamp and fix the rear compression ring 34 and the first flow dividing ring 31 and ensure the sealing of the first arc-shaped flow channel 311. Here, the inner ring clamping bolts 35 and the outer ring clamping bolts 36 can be selected to have a high connection strength, such as high-strength screw connections of grade 12.9 or above can be adopted.

[0048] During the assembly process, in order to facilitate the accurate alignment between the finish-machined surface and the sealing ring surface, and between the material flow channels such as the first material through hole 312 and the feed port of the spiral flow channel 21, multiple positioning pin holes 38 can be respectively formed on the rear compression ring 34, the first flow dividing ring 31, and the spiral die assembly 20.

[0049] In this preferred embodiment, multiple suction holes 41 can also be formed on the peripheral wall of the rear compression ring 34 to suck the air between the outer layer material extruded by the spiral die and the pipe to be compounded through a vacuum pump connected to the suction holes 41 during the operation process, so that the outer layer material is tightly adhered to the pipe running forward (in the direction from right to left in the figure) to complete the compounding of the outer layer material. Among them, a sealing element 42 surrounding the pipe to be compounded can also be provided on the pipe inlet side of the rear compression ring 34, such as a rubber or silicone sealing plate that can fit with the outer peripheral surface of the pipe to be compounded, which is beneficial to the good compounding of the outer layer.

[0050] Figure 3 and Figure 4 shown is a spiral die according to another preferred embodiment of the present invention, which has many similarities or resemblances with the spiral die shown in Figure 2 such as the same die head assembly 10, spiral die assembly 20, heating assembly 50, and the first flow dividing ring 31 and the rear pressing ring 34, etc. The following mainly elaborates on their differences in detail.

[0051] Combined with Figure 5 shown, one difference between this preferred embodiment and the preferred embodiment shown in Figure 2 is that there is a second flow dividing ring 32 stacked with the first flow dividing ring 31. The second flow dividing ring 32 is arranged on the side of the first separating ring 31 facing the spiral die assembly 20, and is provided with a plurality of second arc-shaped flow channels 321 distributed circumferentially (preferably evenly distributed) and second material through holes 322 axially penetrating and extending from both ends of the second arc-shaped flow channel 321. In the assembled state, the first material through hole 312 of the first flow dividing ring 31 corresponds to the middle position of the corresponding second arc-shaped flow channel 321. In the illustrated preferred embodiment, a stream of molten material injected from the radial feed port 313 is divided into two streams by the first material through holes 312 at both ends after passing through the first arc-shaped flow channel 311. These two streams of molten material are further divided into two streams of molten material each (a total of four streams) after passing through the corresponding second arc-shaped flow channels 321 and then through the second material through holes 322. Thus, the molten material can be sequentially shunted and conveyed to the corresponding spiral flow channels 21 through the first arc-shaped flow channel 311, the first material through hole 312, the second arc-shaped flow channel 321, and the second material through hole 322.

[0052] According to the above, corresponding to each first material through hole 312 of the first flow dividing ring 31, a corresponding first arc-shaped flow channel 321 and two second material through holes 322 can be provided on the second flow dividing ring 32, further enabling the molten material to be evenly distributed circumferentially and promoting a more uniform wall thickness of the extruded composite layer. Thus, by adding the second flow dividing ring 32, the spiral die can be applied to the outer layer composite step of large-diameter pipes.

[0053] The second diverter ring 32 can be configured to have the same or similar connection structure as the first diverter ring 31, so as to facilitate the processing and sealing of the second arc-shaped flow channel 321. For example, the second arc-shaped flow channel 321 can be formed on the end face of the second diverter ring 32 facing the first diverter ring 31, and connected to the first diverter ring 31 to seal the second arc-shaped flow channel 321 on the surfaces opposite to each other. To this end, a fine-machined surface can be formed on the side of the first diverter ring 31 facing the second diverter ring 32, and a sealing ring surface located radially inside and radially outside the second arc-shaped flow channel 321 can be formed on the side of the second diverter ring 32 facing the first diverter ring 31, and then axially tightened by using the inner ring clamping bolts and the outer ring clamping bolts, so that the sealing ring surface is sealed and fitted with the fine-machined surface of the first diverter ring 31.

[0054] In other embodiments, a transition ring may be provided between the first diverter ring 31 and the second separation ring 32 to provide a transition connection between the first material through hole 312 and the second arc-shaped flow channel 321 and seal the connection position.

[0055] In addition, in this Figure 3 In the preferred embodiment shown, one end of the flow divider assembly 30 adjacent to the spiral die assembly 20 has a connecting ring 33, which is connected to the spiral die assembly 20 and is formed with a third material through hole 331 for connecting the second material through hole 322 (and the first material through hole 312, etc.) to the spiral flow channel. The connecting ring 33 can be connected to the mold shell 22 and the spiral mold core 23 of the spiral die assembly 20 respectively through a plurality of bolts arranged circumferentially, thereby axially separating the direct connection between the spiral mold core 23 and the first flow divider ring 31 and the second flow divider ring 32, which is conducive to preventing the radial displacement of the spiral mold core 23 caused by the radial feed pressure.

[0056] Combination Figure 5 As shown, the first diverter ring 31, the second diverter ring 32 and the connecting ring 33 are sequentially stacked on one side of the feed end of the spiral die assembly, and have corresponding bolt holes, pin holes and flow channels, thereby diverting and conveying the material flow to the spiral flow channel 21. On this basis, the components of the diverter assembly 30 can be appropriately set to meet different production needs. For example, the number of diverter rings can be further increased to divide the material flow into more circumferentially evenly distributed multiple strands; for another example, the second diverter ring 32 can be directly connected to the spiral die assembly 20 and the connecting ring 33 can be omitted.

[0057] exist Figure 3 In the preferred embodiment shown, a vacuum assembly 40 is also provided, which is connected to the end of the diverter assembly 30 (rear pressure ring 34) away from the spiral die assembly 20, and has a plurality of suction holes 41 on the peripheral wall. Figure 4As shown, the pipe 100 to be compounded can pass through along the central axis of the vacuum pumping assembly 40 (from right to left). For this purpose, a sealing element 42 for fitting with the outer wall surface of the pipe 100 to be compounded can also be provided at the end of the vacuum pumping assembly 40, and the sealing element 42 can be a rubber or silica gel sealing plate. In an alternative embodiment, the suction holes and the sealing element can be arranged on the rear pressing plate 34 as Figure 2 shown.

[0058] Another aspect of the present invention provides a pipe compounding device having the above-mentioned spiral die. The pipe compounding device can use the above-mentioned spiral die to compound a plastic outer layer with a uniform wall thickness on the outer peripheral surface of the pipe 100 to be compounded, significantly improving the product quality.

[0059] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited thereto. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention, including any suitable combination of each specific technical feature. To avoid unnecessary repetition, the present invention will not separately describe various possible combination methods. But these simple modifications and combinations should also be regarded as the content disclosed by the present invention and fall within the protection scope of the present invention.

Claims

1. A spiral die, having a spiral die assembly (20), the spiral die assembly (20) comprising a die shell (22) and a spiral die core (23), a die cavity being formed in the die shell (22), the spiral die core (23) being disposed in the die cavity and a plurality of spiral flow channels (21) spirally extending around the spiral die core (23) being formed between the spiral die core (23) and the die shell (22), characterized in that, include: A flow diverter assembly (30) is arranged at the feed end of the spiral die assembly (20) and comprises a first flow diverter ring (31), wherein the first flow diverter ring (31) is provided with a first arc-shaped flow channel (311) extending in a circumferential direction and connecting the plurality of spiral flow channels (21).

2. The spiral die according to claim 1, characterized in that, The first flow dividing ring (31) is formed with first material through holes (312) extending axially through both ends of the first arc-shaped flow channel (311), so as to be able to divide and convey material flows to a plurality of corresponding spiral flow channels (21) through the first material through holes (312).

3. The spiral die according to claim 1, wherein The first flow dividing ring (31) is provided with a radial feed port (313) which is connected to the first arc-shaped flow channel (311).

4. The spiral die according to claim 1, characterized in that, A rear pressure ring (34) is connected to one end of the diverter assembly (30) facing away from the spiral mold assembly (20); the first arc-shaped flow channel (311) is formed on the side of the first diverter ring (31) facing the rear pressure ring (34); and the rear pressure ring (34) is connected to seal the first arc-shaped flow channel (311) on a surface opposite to the first diverter ring (31).

5. The spiral mold according to claim 4, wherein The rear pressure ring (34) has a finish-machined surface on one side of the surface facing the first diverter ring (31), and the first diverter ring (31) is provided with sealing ring surfaces (37) respectively located radially inside and radially outside the first arc-shaped flow channel (311), and the rear pressure ring (34) is connected so that the sealing ring surface (37) and the finish-machined surface fit each other to seal the first arc-shaped flow channel (311).

6. The spiral mold according to claim 5, wherein The rear pressure ring (34) and the first diverter ring (31) are axially clamped and fixed by a plurality of inner ring clamping bolts (35) respectively located on the radial inner side of the first arc-shaped flow channel (311) and a plurality of outer ring clamping bolts (36) respectively located on the radial outer side, and / or a plurality of positioning pin holes (38) are respectively formed on the first diverter ring (31) and the rear pressure ring (34).

7. The spiral die according to claim 2, characterized in that, The diverter assembly (30) comprises a second diverter ring (32) stacked on the first diverter ring (31) on a side facing the spiral mold assembly (20), the second diverter ring (32) being provided with a plurality of second arc-shaped flow channels (321) distributed along the circumferential direction and second material through holes (322) extending axially through both ends of the second arc-shaped flow channels (321), and the first material through holes (312) corresponding to the middle position of the corresponding second arc-shaped flow channels (321), so as to be able to divert and convey material flows to a plurality of corresponding spiral flow channels (21) in sequence through the first material through holes (312), the second arc-shaped flow channels (321) and the second material through holes (322).

8. The spiral die according to claim 7, characterized in that, The second arc-shaped flow channel (321) is formed on an end surface of the second diverter ring (32) facing the first diverter ring (31), and the first diverter ring (31) and the second diverter ring (32) are connected to seal the second arc-shaped flow channel (321) on surfaces opposite to each other.

9. The spiral die according to claim 2, wherein One end of the shunt component (30) adjacent to the spiral die component (20) has a communication ring (33), which is connected to the spiral die component (20) and is formed with a third material through-hole (331) for communicating the first material through-hole (312) with a plurality of the spiral flow channels (21).

10. The spiral die according to claim 1, wherein One end of the spiral die component (20) far from the shunt component (30) is connected with a die head component (10), which includes a core die (11) and a die orifice (12) arranged around the core die (11). A material extrusion channel (13) communicating the spiral flow channels (21) is formed between the die orifice (12) and the core die (11), and / or The spiral die has a heating component (50), which is arranged to at least surround the spiral die component (20) and the shunt component (30).

11. The spiral die according to claim 1, characterized in that, One end of the shunt component (30) far from the spiral die component (20) is connected with a vacuum pumping component (40), which is arranged to allow the pipe (100) to be compounded to pass through along the central axis, and a plurality of suction holes (41) are arranged on the peripheral surface of the vacuum pumping component (40).

12. A pipeline composite device, characterized in that, The pipe compounding device includes the spiral die according to any one of claims 1 to 11, so as to be able to form a plastic outer layer on the outer peripheral surface of the pipe (100) to be compounded.

Images