CN113787738A - Portable microwave curing double-vacuum repair system and use method thereof - Google Patents
Portable microwave curing double-vacuum repair system and use method thereof Download PDFInfo
- Publication number
- CN113787738A CN113787738A CN202110999082.5A CN202110999082A CN113787738A CN 113787738 A CN113787738 A CN 113787738A CN 202110999082 A CN202110999082 A CN 202110999082A CN 113787738 A CN113787738 A CN 113787738A
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- Prior art keywords
- vacuum
- microwave
- repair system
- curing
- microwave curing
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- 238000011415 microwave curing Methods 0.000 title claims abstract description 30
- 230000008439 repair process Effects 0.000 title claims abstract description 30
- 238000000034 method Methods 0.000 title claims abstract description 21
- 238000010438 heat treatment Methods 0.000 claims abstract description 16
- 238000001723 curing Methods 0.000 claims abstract description 10
- 239000000463 material Substances 0.000 claims abstract description 9
- 239000011358 absorbing material Substances 0.000 claims description 19
- 239000000853 adhesive Substances 0.000 claims description 13
- 230000001070 adhesive effect Effects 0.000 claims description 13
- 230000009977 dual effect Effects 0.000 claims description 11
- 239000004744 fabric Substances 0.000 claims description 9
- 238000007789 sealing Methods 0.000 claims description 9
- 229910000838 Al alloy Inorganic materials 0.000 claims description 4
- 238000002955 isolation Methods 0.000 claims description 3
- 239000007788 liquid Substances 0.000 claims description 3
- 229910052751 metal Inorganic materials 0.000 claims description 3
- 239000002184 metal Substances 0.000 claims description 3
- 230000005855 radiation Effects 0.000 claims description 3
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 claims description 3
- 229910010271 silicon carbide Inorganic materials 0.000 claims description 3
- 238000010521 absorption reaction Methods 0.000 claims description 2
- 238000005498 polishing Methods 0.000 abstract description 3
- 230000008569 process Effects 0.000 description 4
- 239000002131 composite material Substances 0.000 description 3
- 239000011148 porous material Substances 0.000 description 3
- 230000009467 reduction Effects 0.000 description 3
- 238000004026 adhesive bonding Methods 0.000 description 2
- 230000006698 induction Effects 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000032798 delamination Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000004519 grease Substances 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 1
- 229910052753 mercury Inorganic materials 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 238000003847 radiation curing Methods 0.000 description 1
- 239000004576 sand Substances 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 239000004575 stone Substances 0.000 description 1
Images
Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C73/00—Repairing of articles made from plastics or substances in a plastic state, e.g. of articles shaped or produced by using techniques covered by this subclass or subclass B29D
- B29C73/04—Repairing of articles made from plastics or substances in a plastic state, e.g. of articles shaped or produced by using techniques covered by this subclass or subclass B29D using preformed elements
- B29C73/10—Repairing of articles made from plastics or substances in a plastic state, e.g. of articles shaped or produced by using techniques covered by this subclass or subclass B29D using preformed elements using patches sealing on the surface of the article
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C73/00—Repairing of articles made from plastics or substances in a plastic state, e.g. of articles shaped or produced by using techniques covered by this subclass or subclass B29D
- B29C73/24—Apparatus or accessories not otherwise provided for
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C73/00—Repairing of articles made from plastics or substances in a plastic state, e.g. of articles shaped or produced by using techniques covered by this subclass or subclass B29D
- B29C73/24—Apparatus or accessories not otherwise provided for
- B29C73/30—Apparatus or accessories not otherwise provided for for local pressing or local heating
- B29C73/34—Apparatus or accessories not otherwise provided for for local pressing or local heating for local heating
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
- B29L2031/00—Other particular articles
- B29L2031/30—Vehicles, e.g. ships or aircraft, or body parts thereof
- B29L2031/3076—Aircrafts
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Casting Or Compression Moulding Of Plastics Or The Like (AREA)
Abstract
The invention relates to the field of microwave curing repair, in particular to a portable microwave curing double-vacuum repair system and a using method thereof, wherein the system comprises an inner vacuum bag part and an outer vacuum shell part arranged outside the inner vacuum bag part, and the specific steps are as follows: s1, the vacuum interface of the inner vacuum bag part is positioned outside the radiator shell; s2, vacuumizing the inner vacuum bag film; s3, vacuumizing, and starting a microwave heating program; and S4, after the curing is finished, stopping heating, turning off a microwave power supply, removing auxiliary materials, and finishing and polishing the repaired surface.
Description
Technical Field
The invention relates to the field of microwave curing repair, in particular to a portable microwave curing double-vacuum repair system and a using method thereof.
Background
The composite material has the advantages of light weight, high strength, high designability and the like, is widely used in advanced aircrafts, but easily generates damages such as delamination and debonding after long-term service to influence flight safety, particularly impact such as sand and stone, bird collision and the like, generates large-range damage in the thickness direction and in the transverse direction in the composite material structural part, and needs to be repaired in time, but the traditional repairing mode needs repairing time of hours or even more than ten hours.
Microwave curing is a rapid composite repair technique that requires only tens of minutes or even minutes. One of the traditional microwave curing methods for ensuring the molding quality of a workpiece is to perform microwave curing in a closed space, and improve the heating uniformity in the curing process by the cooperative work of a plurality of microwave sources and the rotation of the workpiece, but the technology needs larger equipment volume and is not suitable for repairing the airframe structure of an airplane and particularly not suitable for an external field environment. The other method is to use a small-sized radiator to carry out radiation curing in a scanning mode, but the method has the problems that electromagnetic waves leak in overshoot of a moving radiator, and the problems of long time consumption, large deformation and the like still exist in the manufacturing and repairing process of large-sized parts.
The dual vacuum cures at such a fast time that air in the repair area cannot be effectively removed, resulting in a reduction in repair quality. In order to further improve the repair quality under the condition of ensuring the repair time, the double-vacuum system becomes a simple and easy way with convenient operation. The conventional double vacuum system uses a perforated metal cover placed on the outer layer of the inner bag to form the outer bag, and the pores in the product are further reduced by the pressure difference between the inner and outer bags. Steel materials are the first choice for dual vacuum systems due to their excellent pressure bearing properties. However, this technique requires a high level of operator skill and the double vacuum bag itself is time consuming. Meanwhile, the traditional vacuum bag laying mode can repair the wave absorption property and the temperature detection accuracy of the area material, so that a double-vacuum system suitable for working under the microwave condition and a using method thereof are developed.
Disclosure of Invention
In order to solve the problems, the invention provides a portable microwave curing double-vacuum repair system and a using method thereof.
A portable microwave curing dual vacuum repair system comprising an inner vacuum bag portion and an outer vacuum shell portion disposed outside the inner vacuum bag portion;
the inner vacuum bag part comprises a patch which is arranged on the surface of the machine body structure 15 to be bonded and repaired through structural adhesive, demoulding cloth, an isolating film, wave-absorbing materials, an air-permeable felt which is laid on the wave-absorbing materials so that the wave-absorbing materials can be directly subjected to microwave radiation, and is sequentially laid on the patch in sequence, wherein the demoulding cloth is used for absorbing heat, conducting and compacting workpieces;
the outer vacuum shell part comprises a radiator shell, a vacuum interface I and a vacuum tube which are arranged on the radiator shell, an infrared temperature sensor arranged at one end, far away from the vacuum interface I, of the radiator shell, a microwave emitter part arranged in the inner vacuum bag part, and a nano flexible rubber film pressed at the edge of the inner vacuum bag part for sealing.
The vacuumizing part comprises a second vacuum interface arranged on the periphery of the area to be repaired, a sealing rubber strip attached to the periphery of the breathable felt and an inner vacuum bag film paved on the breathable felt.
The diameter of the second vacuum interface is not more than 3 mm.
The body structure and the patch are made of any material, and the structural adhesive is a thermocurable structural adhesive, such as a high-strength microwave curing structural adhesive.
The wave-absorbing material is a silicon carbide plate, a flexible wave-absorbing soft film and a wave-absorbing liquid bag, and the areas of the demoulding cloth, the isolating film and the wave-absorbing material are larger than the area of the patch.
The radiator shell is of a ladder aluminum alloy table type structure; the length of the nano flexible rubber film is 10-50 mm; the outer skin of the vacuum tube is made of metal, and the radiator shell is connected with a vacuum pump of the host through the vacuum tube; the microwave emitter part is connected with the host machine through a coaxial cable.
A use method of a portable microwave curing double-vacuum repair system comprises the following specific steps:
s1, the vacuum interface of the inner vacuum bag part is positioned outside the radiator shell, so that the tightness can be conveniently checked;
s2, vacuumizing the inner vacuum bag film, and installing a radiator shell of the portable microwave curing equipment at the outer side of the inner vacuum bag film, wherein the bottom area of the radiator shell needs to be larger than the area of the repair part sheet;
s3, vacuumizing, starting a microwave heating program, keeping the medium-low temperature at 40-80 ℃ in the early stage by adopting a pulse microwave heating method, facilitating gas circulation, raising the temperature to the curing temperature in the later stage, and quickly heating and curing;
and S4, after the curing is finished, stopping heating, turning off the microwave power supply, removing the auxiliary material, and finishing and polishing the repaired surface.
And S3, keeping the pressure values of the inner bag and the outer bag stable in the heating process, and removing the pressure of the outer vacuum system in the later stage of temperature reduction.
The invention has the beneficial effects that: according to the invention, a portable double-vacuum system is constructed, bubble pores in a gluing area are reduced, the problems of electromagnetic ignition, uneven heating and temperature induction deviation in the microwave curing process are solved by using the wave-absorbing material, and the problems of complicated operation, high requirement on personnel quality and long operation time consumption of the double-vacuum system are solved by using the inner bag and outer shell type system.
Drawings
The invention is further illustrated with reference to the following figures and examples.
FIG. 1 is a schematic front view of the present invention;
FIG. 2 is a schematic view of the flow structure of the present invention;
description of the drawings: 1. a coaxial cable; 2. a radiator housing; 3. an infrared temperature sensor; 4. a second vacuum interface; 5. sealing rubber strips; 6. a microwave emitter section; 7. a first vacuum interface; 8. an air-permeable felt; 9. an inner vacuum bag film; 10. a nano flexible rubber film; 11. a wave-absorbing material; 12. an isolation film; 13. demolding the cloth; 14. patching; 15. a machine body structure; 16. a vacuum tube.
Detailed Description
In order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the invention is further explained below.
As shown in fig. 1 and 2, a portable microwave curing dual vacuum repair system includes an inner vacuum bag portion and an outer vacuum shell portion disposed outside the inner vacuum bag portion;
the inner vacuum bag part comprises a patch 14 which is arranged on the surface of a machine body structure 15 to be bonded and repaired through structural adhesive, demoulding cloth 13, an isolating film 12, a wave-absorbing material 11, an air-permeable felt 8 and a vacuumizing part, wherein the demoulding cloth 13, the isolating film 12 and the wave-absorbing material 11 are sequentially laid on the patch 14 and are respectively used for absorbing heat, conducting and compacting workpieces, the air-permeable felt 8 is laid on the wave-absorbing material 11 so that the wave-absorbing material 11 can be directly subjected to microwave radiation, and the vacuumizing part is arranged in an area to be repaired of the machine body structure 15;
the outer vacuum shell part comprises a radiator shell 2, a vacuum interface I7 and a vacuum tube 16 which are arranged on the radiator shell 2, an infrared temperature sensor 3 which is arranged on one end of the radiator shell 2 far away from the vacuum interface I7, a microwave emitter part 6 which is arranged in the inner vacuum bag part, and a nano flexible rubber film 10 which is pressed at the edge of the inner vacuum bag part and is used for sealing.
When the vacuum is pumped, the external pressure is controlled to be less than the pressure difference value of the inner bag by 10mm mercury column, so that gas can overflow in the later heating process, and if the vacuum degree is found to be incapable of reaching, sealing grease can be coated on the contact surface of the nanometer flexible rubber film 10 and the inner vacuum bag, so that gas leakage is prevented.
The microwave emitter part 6 is used as an outer-layer vacuum system, an inner-layer vacuum system is constructed above the repair area by using the inner vacuum bag film 9, the vacuum degrees of the two vacuum systems can be independently controlled, and the shape of the microwave emitter part 6 is convenient to be attached to different curvature structures and can be used for sealing.
The vacuumizing part comprises a second vacuum interface 4 arranged on the periphery of the area to be repaired, a sealing rubber strip 5 attached to the periphery of the breathable felt 8 and an inner vacuum bag film 9 laid on the breathable felt 8.
The diameter of the vacuum interface II 4 is not more than 3mm, so that microwave leakage is prevented.
The body structure 15 and the patch 14 are made of any material, and the structural adhesive is a structural adhesive of a thermocurable variety, such as a high-strength microwave curing structural adhesive.
The wave-absorbing material 11 is a silicon carbide plate, a flexible wave-absorbing soft film and a wave-absorbing liquid bag, and the areas of the demoulding cloth 13, the isolating film 12 and the wave-absorbing material 11 are larger than the area of the patch 14.
The radiator housing 2 is a ladder aluminum alloy table structure but is not limited to the ladder aluminum alloy table structure.
The length of the nano flexible rubber film 10 is 10-50 mm; the outer skin of the vacuum tube 16 is made of metal material to prevent microwave leakage, and the radiator shell 2 is connected with a vacuum pump of a host machine through the vacuum tube 16; the microwave emitter part 6 is connected with the host machine through a coaxial cable 1.
According to the invention, a portable double-vacuum system is constructed, bubble pores in a gluing area are reduced, the problems of electromagnetic ignition, uneven heating and temperature induction deviation in the microwave curing process are solved by using the wave-absorbing material 11, and the problems of complicated operation, high requirement on personnel quality and long operation time consumption of the double-vacuum system are solved by using a bag-in-shell type system.
A use method of a portable microwave curing double-vacuum repair system comprises the following specific steps:
s1, the vacuum interface II 4 of the inner vacuum bag part is positioned outside the radiator shell 2, so that the tightness can be conveniently checked;
s2, vacuumizing the inner vacuum bag film 9, and installing the radiator shell 2 of the portable microwave curing equipment at the outer side of the inner vacuum bag film 9, wherein the bottom area of the radiator shell 2 needs to be larger than the area of the repair part;
s3, vacuumizing, starting a microwave heating program, keeping the medium-low temperature at 40-80 ℃ in the early stage by adopting a pulse microwave heating method, facilitating gas circulation, raising the temperature to the curing temperature in the later stage, and quickly heating and curing;
and S4, after the curing is finished, stopping heating, turning off the microwave power supply, removing the auxiliary material, and finishing and polishing the repaired surface.
And S3, keeping the pressure values of the inner bag and the outer bag stable in the heating process, and removing the pressure of the outer vacuum system in the later stage of temperature reduction.
The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are merely illustrative of the principles of the invention, but that various changes and modifications may be made without departing from the spirit and scope of the invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.
Claims (10)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110999082.5A CN113787738A (en) | 2021-08-28 | 2021-08-28 | Portable microwave curing double-vacuum repair system and use method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110999082.5A CN113787738A (en) | 2021-08-28 | 2021-08-28 | Portable microwave curing double-vacuum repair system and use method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113787738A true CN113787738A (en) | 2021-12-14 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110999082.5A Pending CN113787738A (en) | 2021-08-28 | 2021-08-28 | Portable microwave curing double-vacuum repair system and use method thereof |
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| Country | Link |
|---|---|
| CN (1) | CN113787738A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114851601A (en) * | 2022-03-31 | 2022-08-05 | 国营芜湖机械厂 | Self-adaptive portable microwave heating repair bag, manufacturing process and using method |
| CN114851602A (en) * | 2022-04-07 | 2022-08-05 | 国营芜湖机械厂 | Rapid repairing and first-aid repair bag for composite material structure of airplane and repairing method |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20030188821A1 (en) * | 2002-04-09 | 2003-10-09 | The Boeing Company | Process method to repair bismaleimide (BMI) composite structures |
| US20140290832A1 (en) * | 2013-03-28 | 2014-10-02 | Mitsubishi Aircraft Corporation | Repair method of repair target portion, and repair apparatus |
| CN105034415A (en) * | 2015-07-28 | 2015-11-11 | 广州飞机维修工程有限公司 | Double-vacuumizing device and method for repairing civil aircraft composite materials |
| CN106945307A (en) * | 2017-04-01 | 2017-07-14 | 中南大学 | A kind of method that composite heating is carried out to absorbing material |
| CN207190300U (en) * | 2017-08-21 | 2018-04-06 | 昆明理工大学 | A kind of microwave curing stove to technique for aircraft composite solidification |
| EP3815888A1 (en) * | 2019-10-30 | 2021-05-05 | The Boeing Company | Vacuum bag-less composite repair systems and repairs |
-
2021
- 2021-08-28 CN CN202110999082.5A patent/CN113787738A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20030188821A1 (en) * | 2002-04-09 | 2003-10-09 | The Boeing Company | Process method to repair bismaleimide (BMI) composite structures |
| US20140290832A1 (en) * | 2013-03-28 | 2014-10-02 | Mitsubishi Aircraft Corporation | Repair method of repair target portion, and repair apparatus |
| CN105034415A (en) * | 2015-07-28 | 2015-11-11 | 广州飞机维修工程有限公司 | Double-vacuumizing device and method for repairing civil aircraft composite materials |
| CN106945307A (en) * | 2017-04-01 | 2017-07-14 | 中南大学 | A kind of method that composite heating is carried out to absorbing material |
| CN207190300U (en) * | 2017-08-21 | 2018-04-06 | 昆明理工大学 | A kind of microwave curing stove to technique for aircraft composite solidification |
| EP3815888A1 (en) * | 2019-10-30 | 2021-05-05 | The Boeing Company | Vacuum bag-less composite repair systems and repairs |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114851601A (en) * | 2022-03-31 | 2022-08-05 | 国营芜湖机械厂 | Self-adaptive portable microwave heating repair bag, manufacturing process and using method |
| CN114851601B (en) * | 2022-03-31 | 2023-05-12 | 国营芜湖机械厂 | Self-adaptive portable microwave heating repair bag, manufacturing process and using method |
| CN114851602A (en) * | 2022-04-07 | 2022-08-05 | 国营芜湖机械厂 | Rapid repairing and first-aid repair bag for composite material structure of airplane and repairing method |
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Application publication date: 20211214 |