CN113007457A - High-density polyethylene/cross-linked foaming reinforced polyethylene composite double-wall winding pipe - Google Patents
High-density polyethylene/cross-linked foaming reinforced polyethylene composite double-wall winding pipe Download PDFInfo
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- CN113007457A CN113007457A CN201911332338.6A CN201911332338A CN113007457A CN 113007457 A CN113007457 A CN 113007457A CN 201911332338 A CN201911332338 A CN 201911332338A CN 113007457 A CN113007457 A CN 113007457A
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L9/00—Rigid pipes
- F16L9/16—Rigid pipes wound from sheets or strips, with or without reinforcement
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Abstract
The invention relates to a high-density polyethylene/crosslinked foaming enhanced polyethylene composite double-wall winding pipe, which is formed by spirally winding the high-density polyethylene/crosslinked foaming enhanced polyethylene composite pipe and welding the high-density polyethylene/crosslinked foaming enhanced polyethylene composite pipe by using polyethylene hot melt adhesive; the high-density polyethylene/cross-linked foaming reinforced polyethylene composite pipe is a hollow rectangular pipe, the cross-linked foaming reinforced polyethylene pipe is arranged inside the hollow rectangular pipe, and the peripheral coating layer is made of pure high-density polyethylene. The structure endows the high-density polyethylene/cross-linked foaming reinforced polyethylene composite double-wall winding pipe with excellent impact resistance, slow crack propagation resistance and environmental stress cracking resistance, and the high-density polyethylene/cross-linked foaming reinforced polyethylene composite double-wall winding pipe has high buffering, shock absorbing and shock resisting capacity and heat insulation performance, simultaneously greatly reduces the density of the double-wall winding pipe, greatly reduces the cost and has high economic benefit and social benefit.
Description
Technical Field
The invention relates to a pipe, in particular to a high-density polyethylene/cross-linked foaming reinforced polyethylene composite double-wall winding pipe.
Background
Municipal drainage network construction is an indispensable basic condition for urban development, is an irreplaceable basic support for urban and rural construction, and is an inseparable guarantee system for improving ecological environment. In recent years, with the acceleration of the urbanization process in China, the population number and the environmental pressure are increasing, and the government has increased the investment on urban infrastructure year by year. The high-density polyethylene double-wall winding pipe has the advantages of light weight, corrosion resistance, low water resistance coefficient, large water delivery amount, good sealing performance, long service life, smooth outer wall, convenience for quick construction and backfill and the like, and is widely applied to municipal drainage pipe network engineering construction.
The high-density polyethylene double-wall winding pipe wall is formed by alternately and continuously forming a hollow rectangular pipe wall and a solid pipe wall. Because the drainage pipeline is buried relatively deeply and the field construction condition is severe, in the quick construction process of the construction period, the weak hollow rectangular pipe wall wound with the pipeline due to improper storage, transportation, installation and treatment methods or environmental influence is more easily damaged, so that the engineering quality and the service life are influenced; in areas where shallow soft soil generally develops, underground water level changes greatly or human building engineering activities are more, engineering geological disasters such as ground collapse, ground settlement, ground cracks and the like easily occur, and due to movement or deformation of the stratum, the stress condition of a hollow part at the pipe wall of the double-wall winding pipe is complex, and the deformation born locally is larger, the stress is higher and the time is longer; meanwhile, the capacity of the plastic buried drainage pipeline for bearing external pressure is inversely proportional to the third power of the diameter of the pipeline, more polyethylene is needed to be used for preparing the pipeline with the large caliber and the high ring stiffness grade specification to meet the requirement of pressure bearing, and the larger the diameter of the pipeline is, the higher the ring stiffness grade is, and the higher the cost of raw materials is. This limits the application and popularization of the high density polyethylene double-wall winding pipe to a certain extent.
Chinese patent CN106608994A discloses a continuous fiber cloth reinforced double-wall winding pipe with a multi-layer composite structure, which is prepared by introducing continuous fiber cloth into a cloth passing hole and a cloth passing channel of a die in a die head mold, intersecting the cloth with resin from the die head mold, uniformly coating the resin, extruding and vacuum sizing to form a hollow square pipe, spirally winding the hollow square pipe, and welding the hollow square pipe with plastic hot melt adhesive.
Chinese patent CN106608995B also discloses a method for manufacturing a continuous fiber bundle reinforced double-wall wound tube with a multi-layer composite structure, which comprises introducing a continuous fiber bundle into a wire-passing hole and a wire-passing channel in a die, intersecting the resin at the port of the die and uniformly coating the resin, extruding and vacuum sizing to form a hollow square tube, and finally spirally winding the hollow square tube and welding the hollow square tube with plastic hot melt adhesive.
Chinese patent CN202691330U discloses a high density polyethylene/crosslinked polyethylene composite double-wall winding pipe, which is formed by spirally winding a high density polyethylene/crosslinked polyethylene composite pipe and welding the high density polyethylene/crosslinked polyethylene composite pipe with polyethylene hot melt adhesive; the high-density polyethylene/crosslinked polyethylene composite pipe is a hollow rectangular pipe, the inside of the hollow rectangular pipe is a crosslinked high-density polyethylene pipe, and the periphery of the hollow rectangular pipe is a pure high-density polyethylene coating layer. Because the cross-linked high-density polyethylene pipe is arranged in the hollow rectangular pipe, the modulus, the impact resistance, the scratch resistance, the slow crack expansibility resistance, the environmental stress crack resistance, the creep resistance and the high temperature resistance of the hollow square pipe of the pipeline are greatly improved; the periphery of the hollow rectangular pipe is provided with a pure high-density polyethylene coating layer, so that the outer wall of the hollow rectangular pipe can be easily melted and welded, the double-wall winding pipe is enabled to integrally have enough seam tensile strength, and the overall performance of the pipeline is effectively improved.
However, how to prepare a high-density polyethylene double-wall winding pipe with low cost and excellent performance is a problem to be solved.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide a high-density polyethylene/crosslinked foaming reinforced polyethylene composite double-wall winding pipe.
The purpose of the invention can be realized by the following technical scheme:
the invention provides a high-density polyethylene/cross-linked foaming enhanced polyethylene composite double-wall winding pipe which is characterized in that the high-density polyethylene/cross-linked foaming enhanced polyethylene composite double-wall winding pipe is formed by spirally winding and welding by using polyethylene hot melt adhesive;
the high-density polyethylene/cross-linked foaming reinforced polyethylene composite pipe is a hollow rectangular pipe, the cross-linked foaming reinforced polyethylene pipe is arranged inside the hollow rectangular pipe, and the peripheral coating layer is a pure high-density polyethylene coating layer.
In one embodiment of the invention, the radial section structure of the high-density polyethylene/crosslinked foamed reinforced polyethylene composite double-wall wound pipe comprises a crosslinked foamed reinforced polyethylene pipe, pure high-density polyethylene coating layers and polyethylene hot melt adhesive connecting layers connected between the adjacent pure high-density polyethylene coating layers.
In one embodiment of the present invention, the wall thickness of the crosslinked foamed reinforced polyethylene pipe is 85% -97% of the wall thickness of the high density polyethylene/crosslinked foamed reinforced polyethylene composite pipe.
In one embodiment of the present invention, the crosslinked foamed reinforced polyethylene pipe is prepared by melt-mixing polyethylene, a foaming agent and reinforcing fibers on a twin-screw extruder and then extruding. Wherein the mass ratio of the polyethylene to the foaming agent to the reinforcing fiber is 86:6: 10.
In one embodiment of the present invention, the polyethylene raw material used in the preparation process of the crosslinked foamed reinforced polyethylene pipe is organic peroxide crosslinked polyethylene.
In one embodiment of the invention, the organic peroxide crosslinked polyethylene has a degree of crosslinking of 70% or more
In one embodiment of the invention, the foaming agent used in the preparation process of the crosslinked foamed reinforced polyethylene pipe is a compound of azodicarbonamide and zinc oxide, wherein the mass ratio of azodicarbonamide to zinc oxide is 10: 1.
In one embodiment of the present invention, the reinforcing agent used in the preparation process of the cross-linked foamed reinforced polyethylene pipe is carbon fiber or glass fiber.
In one embodiment of the invention, the peripheral coating is extruded from pure high density polyethylene.
Through the melting coextrusion technique, outside pure high density polyethylene coating has fine compatibility with inside crosslinked foaming reinforcing polyethylene pipe, has guaranteed the bulk strength of compound side's pipe, and simultaneously, outlying pure high density polyethylene coating is heated easily to be melted, conveniently welds through the polyethylene hot melt adhesive.
Because the cross-linked foaming reinforced polyethylene pipe is arranged in the hollow rectangular pipe, the hollow square pipe can be ensured to have high modulus, impact resistance, scratch resistance, slow crack propagation resistance, environmental stress cracking resistance and creep resistance, the integral density of the double-wall winding pipe is greatly reduced, and the cost of the double-wall winding pipe is greatly reduced. The periphery of the hollow rectangular pipe is provided with the pure high-density polyethylene coating layer, the coating layer is well compatible with polyethylene hot melt adhesive, and the coating layer is easy to melt and weld, so that the prepared double-wall winding pipe has enough seam tensile strength, and the overall performance of the double-wall winding pipe is effectively improved.
Compared with the prior art, the cross-linked polyethylene foam reinforced pipe is arranged in the hollow rectangular pipe, so that the hollow rectangular pipe is ensured to have high modulus, excellent impact resistance, creep resistance, slow crack propagation resistance and environmental stress cracking resistance, the high-density polyethylene/cross-linked foam reinforced polyethylene composite double-wall winding pipe has high buffering, shock absorption and shock resistance and heat insulation performance, the density of the double-wall winding pipe is greatly reduced, the cost of the double-wall winding pipe is greatly reduced, and the double-wall winding pipe has high economic benefit and social benefit.
Drawings
Fig. 1 is a schematic view showing the appearance of the high-density polyethylene/crosslinked foamed reinforced polyethylene composite double-walled wound pipe in example 1.
Fig. 2 is a schematic view of the radial cross-sectional structure of the high-density polyethylene/crosslinked foamed reinforced polyethylene composite double-walled wound pipe in example 1.
Wherein: 1-high density polyethylene/cross-linked foamed reinforced polyethylene composite pipe; 2-polyethylene hot melt adhesive; 11-crosslinked foamed reinforced polyethylene pipe; 12-pure high density polyethylene coating.
Detailed Description
The invention is described in detail below with reference to the figures and specific embodiments.
Example 1
Referring to fig. 1 and 2, the high density polyethylene/cross-linked foamed reinforced polyethylene composite double-wall winding pipe of the present embodiment is formed by spirally winding a high density polyethylene/cross-linked foamed reinforced polyethylene composite pipe 1 and welding the high density polyethylene/cross-linked foamed reinforced polyethylene composite pipe with a polyethylene hot melt adhesive 2; the high-density polyethylene/cross-linked foaming reinforced polyethylene composite pipe 1 is a hollow rectangular pipe, the inside of the hollow rectangular pipe is a cross-linked foaming reinforced polyethylene pipe 11, and the periphery of the hollow rectangular pipe is a pure high-density polyethylene coating layer 12; the radial section structure of the high-density polyethylene/cross-linked foaming reinforced polyethylene composite double-wall winding pipe comprises a cross-linked foaming reinforced polyethylene pipe 11, pure high-density polyethylene coating layers 12 and polyethylene hot melt adhesive 2 connecting layers connected between the adjacent pure high-density polyethylene coating layers.
The wall thickness of the crosslinked foamed reinforced polyethylene pipe 11 in this embodiment is 85% -97% of the wall thickness of the high density polyethylene/crosslinked foamed reinforced polyethylene composite pipe 1.
The crosslinked foamed reinforced polyethylene pipe is prepared from organic peroxide crosslinked polyethylene, a foaming agent and reinforcing fibers (the mass ratio of the polyethylene to the foaming agent to the reinforcing fibers is 84:6:10), the crosslinking degree of the organic peroxide crosslinked polyethylene for preparing the crosslinked foamed reinforced polyethylene pipe is not less than 70%, the foaming agent is a compound of azodicarbonamide and zinc oxide (the mass ratio of the azodicarbonamide to the zinc oxide is 10:1), and the reinforcing fibers are carbon fibers or glass fibers.
When the high-density polyethylene/cross-linked foam-reinforced polyethylene composite double-wall winding pipe of the embodiment is prepared, firstly, two extruders are adopted to jointly co-extrude the high-density polyethylene-coated cross-linked foam-reinforced polyethylene composite pipe body, namely, one extruder extrudes fused cross-linked foam-reinforced polyethylene, meanwhile, the other extruder extrudes pure high-density polyethylene, a hollow rectangular high-density polyethylene/cross-linked foam-reinforced polyethylene composite pipe is prepared through a composite opening die, the hollow composite pipe with the pipe wall thickness being different from 85 to 97 percent of the whole pipe wall thickness of the internal cross-linked foam-reinforced polyethylene pipe can be prepared by adjusting the clearance of the co-extrusion die or the extrusion speed of the extruders, the hollow composite pipe extruded from the die enters a hollow shaping box, and the hollow rectangular high-density polyethylene/cross-linked foam-reinforced polyethylene pipe bodies with different sizes can be obtained by cooling and shaping through shaping sleeves with different sizes, then, the high-density polyethylene/crosslinked foaming reinforced polyethylene composite double-wall winding pipe is obtained by spiral winding through a double-wall winding pipe forming machine, continuous welding and forming with polyethylene hot melt adhesive extruded by another plastic extruder and fixed-length sawing.
The embodiments described above are described to facilitate an understanding and use of the invention by those skilled in the art. It will be readily apparent to those skilled in the art that various modifications to these embodiments may be made, and the generic principles described herein may be applied to other embodiments without the use of the inventive faculty. Therefore, the present invention is not limited to the above embodiments, and those skilled in the art should make improvements and modifications within the scope of the present invention based on the disclosure of the present invention.
Claims (9)
1. A high density polyethylene/crosslinked foaming enhanced polyethylene composite double-wall winding pipe is characterized in that the high density polyethylene/crosslinked foaming enhanced polyethylene composite double-wall winding pipe is formed by spirally winding and welding by using polyethylene hot melt adhesive;
the high-density polyethylene/cross-linked foaming reinforced polyethylene composite pipe is a hollow rectangular pipe, the cross-linked foaming reinforced polyethylene pipe is arranged inside the hollow rectangular pipe, and the peripheral coating layer is made of pure high-density polyethylene.
2. The double-walled twisted pipe of claim 1, wherein the radial cross-sectional structure of the double-walled twisted pipe comprises a cross-linked and foamed polyethylene, a covering layer of pure high density polyethylene, and a connecting layer of hot melt adhesive connected between the adjacent covering layers of pure high density polyethylene.
3. The double-walled twisted pipe of claim 1, wherein the wall thickness of the said cross-linked foamed reinforced polyethylene pipe is 85% -97% of the wall thickness of the said high density polyethylene/cross-linked foamed reinforced polyethylene pipe.
4. The high-density polyethylene/crosslinked foamed and reinforced polyethylene composite double-wall winding pipe as claimed in claim 1, wherein the crosslinked foamed and reinforced polyethylene pipe is prepared by melt-mixing polyethylene, a foaming agent and reinforcing fibers on a double-screw extruder and then extruding, and the mass ratio of the polyethylene to the foaming agent to the reinforcing fibers is 86:6: 10.
5. The high-density polyethylene/crosslinked foamed and reinforced polyethylene composite double-wall wound pipe according to claim 4, wherein the polyethylene material used in the preparation process of the crosslinked foamed and reinforced polyethylene pipe is organic peroxide crosslinked polyethylene.
6. The high-density polyethylene/crosslinked foamed and reinforced polyethylene composite double-walled winding pipe according to claim 5, wherein the crosslinking degree of the organic peroxide crosslinked polyethylene is not less than 70%.
7. The high-density polyethylene/crosslinked and foamed and reinforced polyethylene composite double-wall winding pipe as claimed in claim 4, wherein the foaming agent used in the preparation process of the crosslinked and foamed reinforced polyethylene pipe is a compound of azodicarbonamide and zinc oxide, wherein the mass ratio of azodicarbonamide to zinc oxide is 10: 1.
8. The double-walled wound pipe of claim 1, wherein the reinforcing agent used in the preparation of the cross-linked foamed reinforced polyethylene pipe is carbon fiber or glass fiber.
9. The high density polyethylene/crosslinked foamed reinforced polyethylene composite double-walled wound pipe according to claim 1, wherein said outer coating layer is prepared by extrusion of pure high density polyethylene.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911332338.6A CN113007457A (en) | 2019-12-22 | 2019-12-22 | High-density polyethylene/cross-linked foaming reinforced polyethylene composite double-wall winding pipe |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201911332338.6A CN113007457A (en) | 2019-12-22 | 2019-12-22 | High-density polyethylene/cross-linked foaming reinforced polyethylene composite double-wall winding pipe |
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| CN113007457A true CN113007457A (en) | 2021-06-22 |
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| CN201911332338.6A Pending CN113007457A (en) | 2019-12-22 | 2019-12-22 | High-density polyethylene/cross-linked foaming reinforced polyethylene composite double-wall winding pipe |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114623293A (en) * | 2022-04-07 | 2022-06-14 | 安庆市悦发管业有限公司 | High strength HDPE winding pipe with spiral twists reverse structure |
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| CN102691832A (en) * | 2012-06-12 | 2012-09-26 | 上海清远管业科技有限公司 | Glass fiber enhanced high-density polyethylene (HDPE) double-walled winding pipe and manufacture method thereof |
| CN102734569A (en) * | 2012-06-11 | 2012-10-17 | 上海清远管业科技有限公司 | High density polyethylene/cross-linked polyethylene compound double-wall coil pipe |
| CN102775668A (en) * | 2012-08-10 | 2012-11-14 | 昆山乔锐金属制品有限公司 | Formula of composite spiral tube material |
| CN105968608A (en) * | 2016-03-23 | 2016-09-28 | 马鞍山金晟工业设计有限公司 | Shell powder enhanced polyvinyl chloride foam tube |
| CN106700209A (en) * | 2015-07-16 | 2017-05-24 | 中国石油化工股份有限公司 | Nano carbon fiber-containing composite foam material and preparation thereof |
| CN108530752A (en) * | 2018-04-24 | 2018-09-14 | 中广核俊尔新材料有限公司 | A kind of continuous Long Glass Fiber Reinforced PP Composite of fretting map and its preparation method and application |
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2019
- 2019-12-22 CN CN201911332338.6A patent/CN113007457A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102734569A (en) * | 2012-06-11 | 2012-10-17 | 上海清远管业科技有限公司 | High density polyethylene/cross-linked polyethylene compound double-wall coil pipe |
| CN102691832A (en) * | 2012-06-12 | 2012-09-26 | 上海清远管业科技有限公司 | Glass fiber enhanced high-density polyethylene (HDPE) double-walled winding pipe and manufacture method thereof |
| CN102775668A (en) * | 2012-08-10 | 2012-11-14 | 昆山乔锐金属制品有限公司 | Formula of composite spiral tube material |
| CN106700209A (en) * | 2015-07-16 | 2017-05-24 | 中国石油化工股份有限公司 | Nano carbon fiber-containing composite foam material and preparation thereof |
| CN105968608A (en) * | 2016-03-23 | 2016-09-28 | 马鞍山金晟工业设计有限公司 | Shell powder enhanced polyvinyl chloride foam tube |
| CN108530752A (en) * | 2018-04-24 | 2018-09-14 | 中广核俊尔新材料有限公司 | A kind of continuous Long Glass Fiber Reinforced PP Composite of fretting map and its preparation method and application |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114623293A (en) * | 2022-04-07 | 2022-06-14 | 安庆市悦发管业有限公司 | High strength HDPE winding pipe with spiral twists reverse structure |
| CN114623293B (en) * | 2022-04-07 | 2023-11-03 | 安庆市悦发管业有限公司 | High-strength HDPE winding pipe with spiral torsion structure |
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Application publication date: 20210622 |