A pipe production mold and pipe production equipment for producing thick-walled pipes with large diameter and uniform wall thickness
By designing a mold including spiral, expansion-shrinkage core, runner structure and cooling mold, the problem of uneven wall thickness of large-diameter thick wall pipes is solved, and the density and service life of the product are improved.
Patent Information
- Application Number
- CN202420393908.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-02-29
- Publication Date
- 2025-04-08
- Estimated Expiration
- 2034-02-28
AI Technical Summary
When producing large-diameter thick-wall pipes, conventional equipment is prone to sagging, resulting in uneven product wall thickness, easy wear and cracking, reducing service life and increasing production and maintenance costs.
A mold including a spirochete, an expansion-shrinking die core, a first and second runner, an inner and outer cooling mold and a heating ring is designed. By setting a flow and cooling of the molten polyethylene to prevent sagging by setting a flow channel structure of an expansion zone, a flat gentle zone and a shrinking zone.
The wall thickness uniformity of large-diameter thick wall pipes is achieved, the compactness and service life of the product are improved, and the production and maintenance costs are reduced.
Smart Images
Figure CN222727348U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of pipe production equipment, in particular to a pipe production mold and pipe production equipment for producing thick-walled pipes with large diameter and uniform wall thickness. Background Art
[0002] The information disclosed in this background technology section is only intended to increase the understanding of the overall background of the utility model, and shall not necessarily be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to ordinary technicians in this field.
[0003] As a highly efficient and durable pipe material, large-diameter PE water pipes have been widely used in many fields, including municipal water supply, sewage treatment, agricultural irrigation, natural gas transportation, and transportation of mineral sand and mud.
[0004] Conventional pipe production molds generally include a spiral body connected to a die base, an outer mold body is provided outside the spiral body, and also includes a mold core and a die disposed outside the die core. The melt enters the spiral body, flows along the spiral groove of the spiral body, and then enters the channel between the die and the die core, and finally flows out of the channel to form. However, when using conventional pipe production molds to produce large-diameter thick-walled pipes, the molten polyethylene raw material will sag, resulting in uneven product wall thickness. The upper wall thickness of the product is the thinnest, and the lower wall thickness of the product is the thickest. The thin wall thickness of the pipe is prone to wear and cracking, thereby reducing the service life of the pipe and increasing production and maintenance costs.
[0005] In the prior art, although some molds that can be used to produce thick-walled pipes are disclosed, they are not suitable for large-diameter pipes. Therefore, there is an urgent need for a mold for producing large-diameter thick-walled pipes with uniform wall thickness. Utility Model Content
[0006] In order to solve the above problems, the utility model provides a mold and a pipe production device for producing thick-walled pipes with large diameter and uniform wall thickness.
[0007] In order to achieve the above technical purpose, the utility model adopts the following technical solutions:
[0008] The first aspect of the utility model provides a mold for producing thick-walled pipes with large diameter and uniform wall thickness, comprising: a spiral body, the spiral body is connected to an expansion-contraction mold core, a first die matching therewith is arranged outside the expansion-contraction mold core, the expansion-contraction mold core is connected to an expansion conveying mold core, a second die matching therewith is arranged outside the expansion conveying mold core, and both the expansion conveying mold core and the second die are connected to a thermal insulation pad; a first flow channel is formed between the expansion-contraction mold core and the first die, a second flow channel is formed between the expansion conveying mold core and the second die, the first flow channel is connected to the second flow channel, the second flow channel is connected to an extrusion flow channel, and an inner cooling mold and an outer cooling mold are respectively arranged on the outer side of the extrusion flow channel.
[0009] In one or more embodiments, from the entry to the exit of the molten polyethylene, the first flow channel includes a first expansion zone, a first gentle zone and a contraction zone. The first expansion zone and the first gentle zone can increase the amount of molten polyethylene in the first flow channel, and the contraction zone can increase the flow rate of the molten polyethylene and improve the density. The entire first flow channel can increase the amount of molten polyethylene and make it dense.
[0010] Preferably, the expansion angle of the first expansion zone is 25° to 45°, and the length of the first expansion zone is 10 to 150 mm.
[0011] Preferably, the length of the first flat zone is 30 to 50 mm, and the height of the first flat zone is 1.3 to 2.0 times the height of the extrusion flow channel.
[0012] Preferably, the contraction angle of the contraction zone is 30° to 60°, and the length of the contraction zone is 30 to 270 mm.
[0013] In one or more embodiments, from the entry to the exit of the molten polyethylene, the second flow channel includes a second expansion zone and a second flat zone, and the second flat zone is connected to the extrusion flow channel. Since the end of the first channel is a contraction zone, in order to ensure that the molten polyethylene can directly fill the entire extrusion flow channel, it is necessary to set the second expansion zone to expand the amount of molten polyethylene.
[0014] Preferably, the second expansion zone has an angle of 30° to 60° and a length of 30 to 300 mm.
[0015] Preferably, the length of the second flat zone is 100-500 mm, and the height of the second flat zone is the same as the height of the extrusion flow channel.
[0016] In one or more embodiments, in order to ensure the molten polyethylene is in a molten state and prevent it from solidifying, the outer sides of the spiral body, the first die and the second die are all connected to a heating ring.
[0017] In one or more embodiments, the inner cooling mold and the outer cooling mold have the same length, and the lengths of both are not less than 3 to 10 times the wall thickness of the tube.
[0018] In one or more embodiments, the working surfaces of the first flow channel and the second flow channel are sprayed with a high temperature resistant non-stick layer.
[0019] In one or more embodiments, the working surfaces of the inner cooling mold and the outer cooling mold are sprayed with a high temperature resistant non-stick layer.
[0020] The second aspect of the utility model provides a pipe production device for producing thick-walled pipes with large diameter and uniform wall thickness, comprising the above-mentioned thick-walled pipe mold for producing large diameter and uniform wall thickness.
[0021] The beneficial effects of the utility model are:
[0022] (1) The traditional process for producing large-diameter thick-walled pipes is to directly immerse the pipes prepared by extrusion of the extrusion channel into water for cooling, which will cause sag, making the product wall thickness uneven. In the utility model, the high-temperature zone and the cooling zone are separated by a heat insulation ring, which can ensure the melting state of the molten polyethylene in the high-temperature zone and the cooling of the molten polyethylene in the cooling zone without affecting each other. The inner cooling mold and the outer cooling mold are directly set on the outside of the extrusion channel, which can directly cool the molten polyethylene from the outside to the inside to prevent sag.
[0023] (2) The first expansion zone of the first flow channel can rapidly expand the amount of molten polyethylene, while the contraction zone can increase the flow rate of the molten polyethylene and improve its density to prevent the occurrence of pores. The expansion zone of the second flow channel further expands the amount of molten polyethylene to reach the extrusion amount required for preparing thick-walled pipes. The combination of the first flow channel and the second flow channel ensures that the prepared thick-walled pipe has no shrinkage pores inside, has high density and can reach the required thickness. BRIEF DESCRIPTION OF THE DRAWINGS
[0024] The drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention.
[0025] Figure 1 This is a schematic structural diagram of a mold for producing thick-walled pipes with large diameter and uniform wall thickness in Example 1 of the present invention;
[0026] Among them, 1-helix, 2-first die, 3-expansion-contraction core, 4-first flow channel, 5-second die, 6-expansion conveying core, 7-second flow channel, 8-inner cooling die, 9-outer cooling die, 10-heating ring, 11-insulation pad and 12 extrusion flow channel. DETAILED DESCRIPTION
[0027] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.
[0028] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present utility model. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.
[0029] Example 1
[0030] See also Figure 1 A mold for producing thick-walled pipes with large diameter and uniform wall thickness, comprising: a spiral body 1, the spiral body 1 is connected to an expansion-contraction core 3, a first die 2 matching therewith is arranged outside the expansion-contraction core 3, the expansion-contraction core 3 is connected to an expansion conveying core 6, a second die 5 matching therewith is arranged outside the expansion conveying core 6, and both the expansion conveying core 6 and the second die 5 are connected to a thermal insulation pad 11; a first flow channel 4 is formed between the expansion-contraction core 3 and the first die 2, a second flow channel 7 is formed between the expansion conveying core 6 and the second die 5, the material flow channel of the spiral body is connected to the first flow channel 4, the first flow channel 4 is connected to the second flow channel 7, the second flow channel 7 is connected to an extrusion flow channel 12, and an inner cooling die 8 and an outer cooling die 9 are respectively arranged on the outer side of the extrusion flow channel 12.
[0031] Since thick-walled pipes need to be prepared, and the amount of molten polyethylene flowing out of the material flow channel of the spiral is too small, directly extruding it into the extrusion flow channel will make the generated thick-walled pipe not dense and bubbles may appear. Therefore, in this embodiment, from the entry to the exit of the molten polyethylene, the first flow channel 4 is provided with a first expansion zone, a first flat zone and a contraction zone. The expansion angle of the first expansion zone is 25° to 45°, and the length of the first expansion zone is 10 to 150 mm. The length of the first flat zone is 30 to 50 mm, and the height of the first flat zone is 1.3 to 2.0 times the height of the extrusion flow channel. The contraction angle of the contraction zone is 30° to 60°, and the length of the contraction zone is 30 to 270 mm. The first expansion zone can quickly expand the amount of molten polyethylene, and the contraction zone can increase the flow rate of the molten polyethylene and improve its density at the same time to prevent the occurrence of pores.
[0032] However, since the contraction zone of the first flow channel reduces the amount of molten polyethylene flowing out, if it is directly extruded into the extrusion flow channel, the generated thick-walled pipe will be loose. Therefore, from the entry to the exit of the molten polyethylene, the second flow channel 7 is provided with a second expansion zone and a second flat zone. The angle of the second expansion zone is 30° to 60°, the length is 30 to 300 mm, the length of the second flat zone is 100 to 500 mm, and the height of the second flat zone is the same as the height of the extrusion flow channel. The expansion zone of the second flow channel 7 expands the amount of molten polyethylene again to reach the extrusion amount required for the preparation of thick-walled pipes. The cooperation of the first flow channel 4 and the second flow channel 7 ensures that the prepared thick-walled pipe has no shrinkage pores inside, high density and can reach the required thickness.
[0033] The molten polyethylene flowing out from the material flow channel of the spiral body 1 passes through the first flow channel 4 and the second flow channel 7 and then enters the extrusion flow channel 12. The molten state of the polyethylene must be ensured in the material flow channel, the first flow channel 4 and the second flow channel 7 of the spiral body 1. In order to prevent the molten polyethylene from solidifying due to the temperature drop when passing through these places, the outer sides of the spiral body 1, the first die 5 and the second die 5 are all connected to the heating ring.
[0034] The molten polyethylene in the second flow channel 7 reaches a set height and enters the extrusion flow channel 12 to generate a thick-walled pipe. In order to prevent the generated thick-walled pipe from drooping, the molten polyethylene in the extrusion flow channel 12 needs to be cooled. The polyethylene needs to be kept in a molten state in the second flow channel 7, but cooling is required in the extrusion flow channel 12. In this embodiment, the expansion conveying mold core 6 and the second die 5 are both connected to the insulation pad 11. The high-temperature zone and the cooling zone are separated by providing an insulation ring, which can ensure the molten state of the molten polyethylene in the high-temperature zone and the cooling of the molten polyethylene in the cooling zone, and the two do not affect each other.
[0035] In order to achieve a better condensation effect, an inner cooling mold 8 and an outer cooling mold 9 are respectively provided on the outer side of the extrusion channel 12. The inner cooling mold 8 and the outer cooling mold 9 have the same length, and the length of both is not less than 3 to 10 times the wall thickness of the pipe.
[0036] The working surfaces of the first flow channel 4 and the second flow channel 7 are sprayed with a high temperature resistant non-stick layer. At the same time, the working surfaces of the inner cooling mold 8 and the outer cooling mold 9 are sprayed with a high temperature resistant non-stick layer. The flow channel surfaces of the mold and the cooling mold are all sprayed with a high temperature resistant non-stick layer to reduce the flow resistance of the molten material, reduce the pressure loss of the molten material in the tube blank, and ensure that the product is dense and has no shrinkage defects.
[0037] This embodiment also provides a pipe production device for producing thick-walled pipes with large diameter and uniform wall thickness, including the above-mentioned thick-walled pipe mold for producing large diameter and uniform wall thickness.
Claims
1. A die for producing thick-walled pipes with large diameter and uniform wall thickness, characterized in that: include: A spiral body, wherein the spiral body is connected to an expansion-contraction mold core, a first die matching therewith is arranged outside the expansion-contraction mold core, the expansion-contraction mold core is connected to an expansion conveying mold core, a second die matching therewith is arranged outside the expansion conveying mold core, and both the expansion conveying mold core and the second die are connected to a thermal insulation pad; a first flow channel is formed between the expansion-contraction mold core and the first die, a second flow channel is formed between the expansion conveying mold core and the second die, the first flow channel is connected to the second flow channel, the second flow channel is connected to the extrusion flow channel, and an inner cooling mold and an outer cooling mold are respectively arranged on the outer side of the extrusion flow channel.
2. The mold for producing thick-walled pipes with large diameter and uniform wall thickness as claimed in claim 1, characterized in that: The first flow channel includes a first expansion area, a first flat area and a contraction area.
3. The mold for producing thick-walled pipes with large diameter and uniform wall thickness as claimed in claim 2, characterized in that: The expansion angle of the first expansion zone is 25° to 45°, and the length of the first expansion zone is 10 to 150 mm.
4. The mold for producing thick-walled pipes with large diameter and uniform wall thickness as claimed in claim 2, characterized in that: The length of the first flat zone is 30 to 50 mm, and the height of the flat zone is 1.3 to 2.0 times the height of the extrusion flow channel.
5. The mold for producing thick-walled pipes with large diameter and uniform wall thickness as claimed in claim 2, characterized in that: The contraction angle of the contraction zone is 30° to 60°, and the length of the contraction zone is 30 to 270 mm.
6. The mold for producing thick-walled pipes with large diameter and uniform wall thickness as claimed in claim 1, characterized in that: The second flow channel includes a second expansion area and a second flat area, and the second flat area is connected to the extrusion flow channel.
7. The mold for producing thick-walled pipes with large diameter and uniform wall thickness as claimed in claim 6, characterized in that: The angle of the second expansion zone is 30° to 60°, and the length is 30 to 300 mm.
8. The mold for producing thick-walled pipes with large diameter and uniform wall thickness as claimed in claim 1, characterized in that: The outer sides of the spiral body, the first die and the second die are all connected to the heating ring.
9. The mold for producing thick-walled pipes with large diameter and uniform wall thickness as claimed in claim 1, characterized in that: The working surfaces of the first flow channel and the second flow channel are sprayed with a high temperature resistant non-stick layer; Alternatively, the working surfaces of the inner cooling mold and the outer cooling mold are sprayed with a high temperature resistant non-stick layer.
10. A pipe production equipment for producing thick-walled pipes with large diameter and uniform wall thickness, characterized in that: The invention comprises the above-mentioned mold for producing thick-walled pipes with large diameter and uniform wall thickness.