CN108281742B - Preparation method of inflation-free elliptical waveguide - Google Patents
Preparation method of inflation-free elliptical waveguide Download PDFInfo
- Publication number
- CN108281742B CN108281742B CN201810053078.8A CN201810053078A CN108281742B CN 108281742 B CN108281742 B CN 108281742B CN 201810053078 A CN201810053078 A CN 201810053078A CN 108281742 B CN108281742 B CN 108281742B
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- Prior art keywords
- inflation
- elliptical waveguide
- waveguide
- tube
- nitrogen
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- 238000002360 preparation method Methods 0.000 title claims description 11
- 239000000945 filler Substances 0.000 claims abstract description 13
- 238000011049 filling Methods 0.000 claims abstract description 8
- 238000000034 method Methods 0.000 claims abstract description 6
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 36
- 229910052757 nitrogen Inorganic materials 0.000 claims description 18
- 229920000642 polymer Polymers 0.000 claims description 17
- 239000004698 Polyethylene Substances 0.000 claims description 15
- -1 polyethylene Polymers 0.000 claims description 15
- 229920000573 polyethylene Polymers 0.000 claims description 15
- 229920001903 high density polyethylene Polymers 0.000 claims description 12
- 239000004700 high-density polyethylene Substances 0.000 claims description 12
- 229920001684 low density polyethylene Polymers 0.000 claims description 12
- 239000004702 low-density polyethylene Substances 0.000 claims description 12
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 9
- 229910052802 copper Inorganic materials 0.000 claims description 9
- 239000010949 copper Substances 0.000 claims description 9
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims description 6
- 238000002347 injection Methods 0.000 claims description 6
- 239000007924 injection Substances 0.000 claims description 6
- 238000004519 manufacturing process Methods 0.000 claims description 6
- 238000004513 sizing Methods 0.000 claims description 6
- 238000003466 welding Methods 0.000 claims description 6
- 238000005187 foaming Methods 0.000 claims description 5
- 238000002156 mixing Methods 0.000 claims description 5
- 239000000203 mixture Substances 0.000 claims description 5
- 238000000465 moulding Methods 0.000 claims description 4
- 239000002667 nucleating agent Substances 0.000 claims description 4
- 229910052786 argon Inorganic materials 0.000 claims description 3
- 238000009833 condensation Methods 0.000 claims description 3
- 230000005494 condensation Effects 0.000 claims description 3
- 239000007789 gas Substances 0.000 claims description 3
- 238000009966 trimming Methods 0.000 claims description 3
- 238000001816 cooling Methods 0.000 claims description 2
- 238000002844 melting Methods 0.000 claims description 2
- 230000008018 melting Effects 0.000 claims description 2
- 230000006641 stabilisation Effects 0.000 claims description 2
- 238000011105 stabilization Methods 0.000 claims description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract description 4
- 238000001035 drying Methods 0.000 abstract description 3
- 230000007774 longterm Effects 0.000 abstract description 2
- 238000003860 storage Methods 0.000 abstract description 2
- 239000000243 solution Substances 0.000 description 3
- 238000012423 maintenance Methods 0.000 description 2
- 229920003023 plastic Polymers 0.000 description 2
- 239000004033 plastic Substances 0.000 description 2
- 230000032683 aging Effects 0.000 description 1
- 230000010261 cell growth Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 239000003989 dielectric material Substances 0.000 description 1
- 238000004049 embossing Methods 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 238000005429 filling process Methods 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
- H01P3/00—Waveguides; Transmission lines of the waveguide type
- H01P3/12—Hollow waveguides
- H01P3/122—Dielectric loaded (not air)
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
- C08J9/04—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent
- C08J9/12—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent by a physical blowing agent
- C08J9/122—Hydrogen, oxygen, CO2, nitrogen or noble gases
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
- H01P11/00—Apparatus or processes specially adapted for manufacturing waveguides or resonators, lines, or other devices of the waveguide type
- H01P11/001—Manufacturing waveguides or transmission lines of the waveguide type
- H01P11/002—Manufacturing hollow waveguides
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
- H01P3/00—Waveguides; Transmission lines of the waveguide type
- H01P3/12—Hollow waveguides
- H01P3/127—Hollow waveguides with a circular, elliptic, or parabolic cross-section
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2203/00—Foams characterized by the expanding agent
- C08J2203/06—CO2, N2 or noble gases
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2323/00—Characterised by the use of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Derivatives of such polymers
- C08J2323/02—Characterised by the use of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Derivatives of such polymers not modified by chemical after treatment
- C08J2323/04—Homopolymers or copolymers of ethene
- C08J2323/06—Polyethene
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2423/00—Characterised by the use of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Derivatives of such polymers
- C08J2423/02—Characterised by the use of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Derivatives of such polymers not modified by chemical after treatment
- C08J2423/04—Homopolymers or copolymers of ethene
- C08J2423/06—Polyethene
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Manufacturing & Machinery (AREA)
- Extrusion Moulding Of Plastics Or The Like (AREA)
Abstract
The invention provides an inflation-free elliptical waveguide, comprising: a low loss dielectric filler, an elliptical waveguide, and an outer jacket; the elliptical waveguide tube is internally filled with the low-loss dielectric filling body; the outer sheath is coated on the outer wall of the elliptical waveguide tube. The method has the advantages that by filling the low-loss medium, no gas exists in the waveguide tube, the condition that water vapor flows back into the waveguide tube due to air pressure difference does not exist, and long-term drying in the elliptical waveguide tube can be ensured on the premise of not using air inflation equipment; and the mechanical strength of the waveguide tube can be slightly increased, and the convenience in storage and use is improved.
Description
Technical Field
The invention relates to a waveguide and a preparation method thereof, in particular to an inflation-free elliptical waveguide and a preparation method thereof.
Background
Under the condition of insolation of intense sun, the black outer sheath of the waveguide tube absorbs more heat, so that the overall temperature of the waveguide tube is more than 50 ℃. Once suddenly rained, it causes a sudden drop in temperature within the waveguide. In this case, a large pressure difference is formed between the air pressure inside and outside the waveguide, so that the water vapor outside the waveguide is sucked back into the waveguide. Condensation into droplets after vapor intrusion can affect waveguide attenuation and reflection properties.
The prior art is that dry air is filled in a waveguide tube to keep a positive pressure difference (10-30 KPa), and dry air inflator equipment is maintained regularly, so that the phenomenon of water vapor back suction caused by internal and external pressure difference change can be prevented; it is ensured that the waveguide remains dry. However, the waveguide often has problems of improper installation, aging of the waveguide, high-low temperature difference and the like, so that the waveguide leaks. Thus, the construction cost and the maintenance cost of the waveguide tube are high; the energy consumption for use increases.
Disclosure of Invention
The invention provides an inflation-free elliptical waveguide and a preparation method thereof, which ensure that the waveguide does not need internal inflation, reduces production and equipment maintenance, and can be used in a working environment without inflation; filling low-loss medium, and guaranteeing drying in the waveguide tube; solves the problems of the prior art to overcome the defects of the prior art.
The invention provides an inflation-free elliptical waveguide, comprising: a low loss dielectric filler, an elliptical waveguide, and an outer jacket; the elliptical waveguide tube is internally filled with the low-loss dielectric filling body; the outer sheath is coated on the outer wall of the elliptical waveguide tube.
Further, the present invention provides an inflation-free elliptical waveguide, which may also have the following features: the low loss dielectric filler is foamed polyethylene.
Further, the present invention provides an inflation-free elliptical waveguide, which may also have the following features: the foamed polyethylene includes: high Density Polyethylene (HDPE) and Low Density Polyethylene (LDPE); the mass parts of the high-density polyethylene (HDPE) are as follows: 70-80 parts; the mass parts of the Low Density Polyethylene (LDPE) are as follows: 20-30 parts.
Further, the present invention provides an inflation-free elliptical waveguide, which may also have the following features: the expanded polyethylene further comprises: 0.01-1 part of nucleating agent.
In addition, the invention provides a preparation method of the inflation-free elliptical waveguide, which comprises the following steps: preparing and molding a circular tube; filling a low-loss dielectric filler in the circular tube; preparing a circular pipe into a circular corrugated pipe; flattening the circular corrugated pipe to form an elliptical waveguide pipe; extruding outside the elliptical waveguide tube to cover the outer sheath.
Further, the invention provides a preparation method of the inflation-free elliptical waveguide, which can also have the following characteristics: the low-loss dielectric filler is formed by physical foaming, and comprises the following steps of melting and mixing polymers to obtain uniform polymer melt; injecting nitrogen into the polymer melt; mixing the polymer melt with nitrogen to nucleate, and forming cells; extruding the mixture of polymer melt and nitrogen into a circular tube, releasing pressure, and causing cells to grow; cooling, cell stabilization and condensation of the insulating structure.
Further, the invention provides a preparation method of the inflation-free elliptical waveguide, which can also have the following characteristics: the nitrogen injection pressure is 400-500 Bar, and the nitrogen is injected through an air injection needle.
Further, the present invention provides an inflation-free elliptical waveguide, which may also have the following features: extruding a mixture of the polymer melt and nitrogen into the circular tube using an extruder; the die core of the extruder is matched with the size of the circular tube.
Further, the invention provides a preparation method of the inflation-free elliptical waveguide, which can also have the following characteristics: the circular tube is manufactured and molded; the method comprises the following steps of trimming the copper strip to a preset width; forming a tube shape through a plurality of forming dies; welding joints by adopting an argon arc welding process; sizing the sizing die to form the copper pipe with the required diameter.
The invention provides an inflation-free elliptical waveguide, which is filled with low-loss medium, so that no gas exists in the waveguide, and the condition that water vapor flows backward into the waveguide due to air pressure difference is avoided, and long-term drying in the elliptical waveguide can be ensured on the premise of not using inflation equipment; and the mechanical strength of the waveguide tube can be slightly increased, and the convenience in storage and use is improved.
Drawings
FIG. 1 is a cross-sectional view of a non-aerated elliptical waveguide.
Fig. 2 is a semi-sectional view of an inflation-free elliptical waveguide.
Detailed Description
The invention is further described below with reference to the drawings and specific embodiments.
As shown in fig. 1 and 2, in this embodiment, the inflation-free elliptical waveguide includes: a low loss dielectric filler 10, an elliptical waveguide 20, and an outer jacket 30. The elliptical waveguide 20 is internally filled with a low-loss dielectric filler 10. The low loss dielectric filler 10 fills the corrugations of the elliptical waveguide 20. The outer sheath 30 is wrapped around the outer wall of the elliptical waveguide 20.
In this embodiment, the low-loss dielectric filler 10 is physically foamed polyethylene; of course, other similar low loss dielectric materials may be used, as long as attenuation and reflection are not affected, and are not specifically shown. The physical foaming polyethylene is formed by mixing High Density Polyethylene (HDPE), low Density Polyethylene (LDPE) and a small amount of nucleating agent. In the proportion, the mass part of the high-density polyethylene (HDPE) is 70-80 parts; the mass portion of the Low Density Polyethylene (LDPE) is 20-30 portions; 0.01-1 part of nucleating agent. The elliptical waveguide 20 is made of copper.
The preparation method of the inflation-free elliptical waveguide comprises the following steps:
and A, preparing and molding the circular tube.
Trimming the copper strip to a predetermined width. The copper strip is formed into a tube shape through a plurality of forming dies. And welding the joint by adopting argon arc welding to form the pipe. And sizing the pipe by using a sizing die to form the copper pipe with the required diameter.
And B, filling a low-loss dielectric filler in the circular tube.
Foaming and filling process of low-loss dielectric filler foamed polyethylene:
The polyethylene polymer is melted and mixed to obtain a homogeneous polyethylene polymer melt. Injecting nitrogen into the polyethylene polymer melt; the nitrogen injection system pressurizes the nitrogen to 400-500 Bar, and the nitrogen is injected into the foaming host machine through the gas injection needle. The polyethylene polymer melt was mixed with nitrogen to nucleate and form cells. Finally, the mixture of polyethylene polymer melt and nitrogen was extruded through a crosshead extruder into a round tube, the pressure was released, resulting in cell growth. The foamed polyethylene cools within the circular tube, the cells stabilize and the insulation structure coagulates.
The mould core of the plastic extruding machine can be replaced, and the mould core of the plastic extruding machine is matched with the size of the round pipe, and the range is phi 10-phi 80mm.
And C, preparing the round pipe into a round corrugated pipe through a embossing machine head.
And D, flattening the circular corrugated pipe by flattening equipment to form an elliptical waveguide tube.
And E, extruding and molding outside the elliptical waveguide tube to cover the outer sheath.
The above specific embodiments only describe the main features and innovative points of the present solution. It will be appreciated by those skilled in the art that the present solution is not limited by the above embodiments. Various changes and modifications can be made in the present solution without departing from the innovative points and the protective scope, which shall fall within the scope of the invention as claimed. The scope of the protection sought is as set forth in the claims below and equivalents thereof.
Claims (7)
1. A preparation method of an inflation-free elliptical waveguide is characterized by comprising the following steps: comprises the steps of,
Step A, preparing and forming a copper round tube;
Step B, filling a low-loss dielectric filler in the circular tube;
The low-loss dielectric filling body is formed by physical foaming, and comprises the following steps: melting and mixing the polymers to obtain a uniform polymer melt; injecting nitrogen into the polymer melt; mixing the polymer melt with nitrogen to nucleate, and forming cells; extruding the mixture of polymer melt and nitrogen into a circular tube, releasing pressure, and causing cells to grow; cooling, cell stabilization and condensation of the insulating structure;
Step C, manufacturing a circular corrugated pipe from the circular pipe;
Step D, flattening the circular corrugated pipe to form an elliptical waveguide pipe;
and E, extruding and molding outside the elliptical waveguide tube to cover the outer sheath.
2. A method of making an inflation-free elliptical waveguide as in claim 1, wherein: wherein, the nitrogen injection pressure is 400-500 Bar, and the nitrogen is injected through a gas injection needle.
3. A method of making an inflation-free elliptical waveguide as in claim 1, wherein: extruding a mixture of the polymer melt and nitrogen into the circular tube using an extruder; the die core of the extruder is matched with the size of the circular tube.
4. A method of making an inflation-free elliptical waveguide as in claim 1, wherein: the circular tube is manufactured and molded; comprises the steps of,
Trimming the copper strip to a preset width; forming a tube shape through a plurality of forming dies; welding joints by adopting an argon arc welding process; sizing the sizing die to form the copper pipe with the required diameter.
5. A method of making an inflation-free elliptical waveguide as in claim 1, wherein: the low-loss dielectric filler is foamed polyethylene.
6. The method for preparing the inflation-free elliptical waveguide of claim 5, wherein: the foamed polyethylene includes: high Density Polyethylene (HDPE) and Low Density Polyethylene (LDPE);
The high-density polyethylene (HDPE) comprises the following components in parts by weight: 70-80 parts;
the mass parts of the Low Density Polyethylene (LDPE) are as follows: 20-30 parts.
7. The method for preparing the inflation-free elliptical waveguide of claim 5, wherein: the expanded polyethylene further comprises: 0.01-1 part of nucleating agent.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810053078.8A CN108281742B (en) | 2018-01-17 | 2018-01-17 | Preparation method of inflation-free elliptical waveguide |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810053078.8A CN108281742B (en) | 2018-01-17 | 2018-01-17 | Preparation method of inflation-free elliptical waveguide |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108281742A CN108281742A (en) | 2018-07-13 |
| CN108281742B true CN108281742B (en) | 2024-06-18 |
Family
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810053078.8A Active CN108281742B (en) | 2018-01-17 | 2018-01-17 | Preparation method of inflation-free elliptical waveguide |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108281742B (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105103369A (en) * | 2013-04-03 | 2015-11-25 | 索尼公司 | Waveguide, waveguide manufacturing method, and wireless transfer system |
| CN207910043U (en) * | 2018-01-17 | 2018-09-25 | 上海阖煦微波技术有限公司 | Exempt to inflate elliptical waveguide |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1233469A3 (en) * | 2001-01-26 | 2003-07-30 | Spinner GmbH Elektrotechnische Fabrik | Waveguide fitting |
| DE102006015338A1 (en) * | 2006-04-03 | 2007-10-11 | Vega Grieshaber Kg | Waveguide transition for producing circularly polarized waves for filling level radar has two lines and planar emitter element that interact with each other to couple one polarized electromagnetic transmitting signal to waveguide |
| JP4805712B2 (en) * | 2006-04-04 | 2011-11-02 | 島田理化工業株式会社 | Power terminator using aqueous medium |
| CN101399391A (en) * | 2007-09-30 | 2009-04-01 | 孙炳元 | Wideband non-loss mixing method for high-frequency signal |
| CN101582529A (en) * | 2009-05-26 | 2009-11-18 | 上海大学 | High medium small scale round waveguide with attenuation |
| CN103035331B (en) * | 2012-12-13 | 2015-08-26 | 苏州亨利通信材料有限公司 | Water vapor gasket for packing and manufacturing process thereof |
| CN104166199B (en) * | 2012-12-13 | 2017-02-15 | 苏州亨利通信材料有限公司 | Manufacturing method of foaming filler rope |
| EP3249742B1 (en) * | 2015-03-31 | 2021-04-28 | Daikin Industries, Ltd. | Dielectric waveguide line |
| CN206379450U (en) * | 2016-11-26 | 2017-08-04 | 西南电子技术研究所（中国电子科技集团公司第十研究所） | Two-band radio frequency signal transmission line |
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2018
- 2018-01-17 CN CN201810053078.8A patent/CN108281742B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105103369A (en) * | 2013-04-03 | 2015-11-25 | 索尼公司 | Waveguide, waveguide manufacturing method, and wireless transfer system |
| CN207910043U (en) * | 2018-01-17 | 2018-09-25 | 上海阖煦微波技术有限公司 | Exempt to inflate elliptical waveguide |
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| CN108281742A (en) | 2018-07-13 |
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