CN112477190A - Integrated manufacturing process for hat-shaped stringer composite material wallboard - Google Patents
Integrated manufacturing process for hat-shaped stringer composite material wallboard Download PDFInfo
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- CN112477190A CN112477190A CN202011060714.3A CN202011060714A CN112477190A CN 112477190 A CN112477190 A CN 112477190A CN 202011060714 A CN202011060714 A CN 202011060714A CN 112477190 A CN112477190 A CN 112477190A
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- Prior art keywords
- hat
- stringer
- shaped
- shaped stringer
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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
- B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
- B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
- B29C70/28—Shaping operations therefor
- B29C70/30—Shaping by lay-up, i.e. applying fibres, tape or broadsheet on a mould, former or core; Shaping by spray-up, i.e. spraying of fibres on a mould, former or core
- B29C70/34—Shaping by lay-up, i.e. applying fibres, tape or broadsheet on a mould, former or core; Shaping by spray-up, i.e. spraying of fibres on a mould, former or core and shaping or impregnating by compression, i.e. combined with compressing after the lay-up operation
-
- 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
Abstract
The invention discloses an integrated manufacturing process of a hat-shaped stringer composite material wallboard, which comprises the following steps: stacking and compacting fewer layers of prepregs to prepare a prepreg thin-layer material sheet; extruding and bending the prepreg thin-layer material sheet to form a hat-shaped stringer pre-pressing material sheet; laying the hat-shaped stringer pre-pressing material sheet in a hat-shaped stringer female die in an integrated forming die, and respectively compacting the hat top, the hat waist, the hat edge and the R-angle transition region of the hat-shaped stringer by using multiple special-shaped press rollers; performing edge cleaning treatment on the compacted hat-shaped stringer; placing the support structure into the groove in the hat-shaped stringer, and laying the skin; and curing and forming after the covering is laid. In the process, the thin-layer material sheet is repeatedly paved and is combined with multiple press rolls to be repeatedly rolled, so that the material sheet is tightly attached to the cap-shaped stringer female die along with the shape, the fibers in the R-angle area of the cap-shaped stringer are not folded, the material sheet is compacted in place, and the conditions of buckling, bridging and the like of the fibers in the R-angle area of the cap-shaped stringer are prevented.
Description
Technical Field
The invention relates to the technical field of aerospace and composite material forming processes, in particular to an integrated manufacturing process of a hat-shaped stringer composite material wallboard.
Background
The composite stringers are the primary support members for the composite fuselage structure and are connected to the fuselage skin by co-cementing or co-curing processes. Because the hat stringers are the most stable structure, more than 90% of the fuselage stringers are hat-shaped. Therefore, how to efficiently and high-quality integrally manufacture hat type stringer composite panels is the key of composite fuselage manufacture.
At present, cap-shaped stringers mainly comprise a hand laying process, a thermal diaphragm process and an automatic rolling process. The hand laying process is to lay the stringer preformed body on a male die tool by hand, to be co-glued and formed with the skin after the stringer is solidified, or to transfer the stringer preformed body to a fuselage integral die to be co-solidified with the skin. The special-shaped stringer with a complex shape can be laid and pasted manually without any professional automatic equipment, but the precision is not high, the quality consistency is difficult to guarantee, and the requirement for large-scale manufacturing of the composite material hat-shaped stringer cannot be met.
The thermal diaphragm process is characterized in that under the condition of vacuumizing, fiber laying layers in a stringer plane material sheet heated to a certain temperature are driven to slide between layers by utilizing the extension of a diaphragm material, the plane material sheet is bent into a cross section of a hat-shaped stringer on a hat-shaped stringer tool, and the hat-shaped stringer thermal diaphragm process forming is completed. The thermal diaphragm equipment has higher production efficiency, but a bridge and a material sheet bend are easily formed in an R-angle area, and the curing quality of parts at the later stage is seriously influenced.
The automatic rolling technology is to combine an automatic feeding and traction system, heat the combined material sheet to a set temperature in a forming tool, and roll and form the stringer perform by arranging different combined roller mechanisms, for example, the patent applications with publication numbers CN 110962367 a and CN 110733190a all adopt rolling technology. Various stringers of this technique ability continuous batch production, nevertheless still adopt the tablet to turn over the scheme owing to still, the regional quality that still is difficult to guarantee of R angle, this scheme also needs the mould to shift simultaneously, increases the shaping step, is difficult to guarantee the precision.
Disclosure of Invention
In order to overcome the problems in the prior art, the invention provides an integrated manufacturing process of a hat-shaped stringer composite wallboard, which adopts the following specific technical scheme:
an integrated manufacturing process for hat stringer composite panels, comprising:
(1) stacking and compacting fewer layers of prepregs to prepare a prepreg thin-layer material sheet;
(2) extruding and bending the prepreg thin-layer material sheet to form a hat-shaped stringer pre-pressing material sheet;
(3) laying the hat-shaped stringer pre-pressing material sheet in a hat-shaped stringer female die in an integrated forming die, and respectively compacting the hat top, the hat waist, the hat edge and the R-angle transition region of the hat-shaped stringer by using multiple special-shaped press rollers;
(4) performing edge cleaning treatment on the compacted hat-shaped stringer;
(5) placing the support structure into the groove in the hat-shaped stringer, and laying the skin;
(6) and curing and forming after the covering is laid.
In the integrated forming process of the hat-shaped stringer composite material wallboard, the laying of the hat-shaped stringer adopts a few layers of prepreg thin-layer material sheets, so that an R-angle area is easier to follow, the material sheets can be compacted in place by rolling through a special-shaped press roller to prevent bridging, the hat-shaped stringer and a skin can be laid on the same die through the integrated forming die, the die does not need to be rotated, and the precision is ensured.
Several alternatives are provided below, but not as an additional limitation to the above general solution, but merely as a further addition or preference, each alternative being combinable individually for the above general solution or among several alternatives without technical or logical contradictions.
Optionally, in step (1), no more than 8 layers of prepreg are used. That is, the number of prepreg layers or ultra-thin prepregs as small as possible is used to manufacture the thin-layer web, or this step may be performed during the prepreg manufacturing process and customized by the prepreg manufacturer.
Optionally, in step (2), the sheet of prepreg laminate is subjected to a heat treatment.
Optionally, in the step (2), the prepreg thin-layer material sheet is extruded and bent by using a hat-shaped stringer performing die and then is preformed, and the hat-shaped stringer performing die is preheated.
Further optionally, the preheating temperature of the hat type stringer pre-forming die is 50 ℃ to 90 ℃.
Optionally, the multiple special-shaped press rollers include a cap top compaction press roller, a cap waist compaction press roller, a cap edge compaction press roller, an R area compaction press roller and an integral compaction press roller which are sequentially arranged.
In this application, to different positions such as crown, cap waist, cap reason and R angle transition region, adopt heterotypic multiple compression roller to carry out the compaction respectively, guarantee the compaction effect. The first compression roller is used for compacting the hat top, the second compression roller is used for compacting the hat waist, the third compression roller is used for compacting the hat edge, the fourth compression roller is used for compacting the R-angle area, and the fifth compression roller is used for compacting the whole body. A plurality of groups of gradual change molds are adopted to extrude and bend the thin-layer prepreg for many times, so that the material sheet can be slowly deformed, and the material sheet does not generate wrinkles.
Optionally, repeating the step (3) until the prepreg reaches a set layer thickness, and obtaining a single hat-shaped stringer preform.
Optionally, in the step (3), the integrated molding die is subjected to a heating treatment. Further optionally, the heating temperature is 50 ℃ to 90 ℃.
In addition, in this application, after the compaction in step (3) is completed, the process cover plate can be covered on the prepreg, and then pre-pumping is performed, so that the hat-shaped stringer preform is compacted.
Optionally, the support structure is made of a light material, including air bags, honeycomb or foam; the supporting structure is designed according to the hat-shaped stringer, so that the skin is guaranteed to be paved and pasted smoothly, and the supporting structure is suitable for automatic paving.
And (6) covering the composite material wallboard preformed body containing the hat-shaped stringer with a curing cover plate, arranging a vacuum bag between the curing cover plate and the integrated forming mold, sealing, vacuumizing, and compacting and curing.
Compared with the prior art, the invention has the beneficial effects that:
in the integrated forming process of the hat-type stringer composite wallboard, the hat-type stringer female die is automatically laid, the thin-layer material sheet is laid for multiple times and is combined with the multiple press rolls for multiple times of rolling, the material sheet is tightly attached to the hat-type stringer female die along with the forming, fibers in the R-angle area of the hat-type stringer are not folded, the material sheet is compacted in place, the conditions of buckling, bridging and the like of the fibers in the R-angle area of the hat-type stringer are prevented, the hat-type stringer and the skin can be laid on the same die through integrated laying forming, the die does not need to be rotated, and the precision is guaranteed.
Drawings
FIG. 1 is a schematic illustration of a prepreg ply preparation for the hat stringer composite panel integrated molding process of the present invention;
FIG. 2 is a schematic view of an automated placement apparatus for the hat stringer composite panel integrated molding process of the present invention;
FIG. 3 is a multi-roll compaction side view of the hat stringer composite panel integrated molding process of the present invention;
FIG. 4 is a schematic illustration of the hat stringer lay-up compaction process of the hat stringer composite panel integrated molding process of the present invention;
FIG. 5 is a schematic illustration of a skin lay-up compaction process of the hat stringer composite panel integrated molding process of the present invention;
FIG. 6 is a schematic view of an integrated cure-molding bag of the hat stringer composite panel integrated molding process of the present invention;
FIG. 7 is an integrated curing profile cross-sectional view of the hat stringer composite panel integrated molding process of the present invention.
In the figure:
1. a unidirectional prepreg roll; 2. backing paper rolls; 3. a thin-layer material coil; 4. a unidirectional prepreg tape; 5. a compression roller; 6. a prepreg thin-layer material sheet; 7. backing paper; 8. a hat stringer female die; 9. a cap top compaction press roller; 10. a cap waist compaction roller; 11. cap edge compaction press rolls; 12. an R area compaction compression roller; 13. integrally compacting a compression roller; 14. automatic laying equipment for hat-shaped stringers; 15. a thin-layer material coil loading device; 16. backing paper collection equipment; 17. a guide wheel; 18. a mold preheating device; 19. an ultrasonic cutting knife; 20. a hat stringer preform; 21. a cap stringer pre-forming die; 22. a support structure; 23. a skin preform; 24. a press roller of the fiber spreading machine; 25. an integrated molding die; 26. curing the cover plate; 27. vacuum bag; 28. and sealing the adhesive tape.
Detailed Description
In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, however, the present invention may be practiced in other ways than those specifically described herein, and thus the present invention is not limited to the specific embodiments disclosed below.
Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.
In this embodiment, the integrated forming process of the hat-shaped stringer composite material wall plate includes the following specific steps:
s1, overlapping and compacting few layers of unidirectional prepreg layers to prepare a prepreg thin-layer material sheet;
s2, extruding and bending the prepreg thin-layer material sheet through a plurality of groups of hat type stringer prefabricated dies to form hat type stringer pre-pressing material sheets;
s3, laying the hat-shaped stringer pre-pressing material sheet in a hat-shaped stringer female die in the integrated forming die, and compacting by utilizing a multi-press roll;
s4, repeating S1, S2 and S3 until the prepreg reaches a set layer thickness, preparing a single hat-shaped stringer preform, and then finishing the laying of all hat-shaped stringer preforms in the integrated forming die by using the same method;
s5, cleaning the edges of the hat-shaped stringer prefabricated body to obtain the hat-shaped stringer prefabricated body with the size of a clean boundary;
s6, placing a support structure in the cap-shaped stringer performing body, and performing skin laying by using an automatic laying process to complete an integrated laying process of the composite material wall plate containing the cap-shaped stringer;
s7, placing the composite material wall plate forming tool on a curing process platform for pre-pumping and curing treatment, and finishing the integral laying and forming of the hat-shaped stringer composite material wall plate.
The specific operation process of the process steps is as follows with reference to the attached drawings 1-7:
1. as shown in fig. 1, four unidirectional prepreg rolls 1 and a backing paper roll 2 are placed together on a laminate pre-forming apparatus, four unidirectional prepregs 4 and a backing paper 7 are drawn, passed through a press roll 5, rolled into a prepreg laminate 6, and wound together with the backing paper on a core to form a laminate roll 3.
2. As shown in fig. 2, a sheet material roll 3 is set on a sheet material roll loading device 15, a prepreg sheet material 6 is drawn out, a backing paper 7 is separated by a guide wheel 15, and the backing paper 7 is recovered by a backing paper hand device 14. In the laying process, a mold preheating device 18 firstly heats the mold to 50-90 ℃, a prepreg sheet is preformed by a cap-shaped stringer preforming mold 21 and laid on a cap-shaped stringer female mold 8, an automatic cap-shaped stringer laying device 14 moves leftwards, a cap top compaction compression roller 9, a cap waist compaction compression roller 10, a cap edge compaction compression roller 11, an R area compaction compression roller 12 and an integral compaction compression roller 13 are sequentially used for compacting the thin-layer sheet laid on the mold, and after the thin-layer sheet is laid to a designated position, an ultrasonic cutting knife 19 is used for cutting. The automated placement equipment 14 for hat stringers is again run to the start and the above work is repeated until the hat stringer preform 20 reaches the specified thickness.
3. The specific cap stringer laying mode is shown in fig. 3 and 4, cap stringer laying is carried out by adopting a multi-rolling mode, a prepreg thin-layer material sheet 6 is bent close to a cap stringer preforming die 21 and then is placed on a cap stringer female die 8 in a proper manner, a cap top compaction compression roller 9, a cap waist compaction compression roller 10 and a cap edge compaction compression roller 11 are used for respectively compacting a cap top, a cap waist and a cap edge to prevent wrinkles and bridging, then an R area compaction compression roller 12 is used for carrying out secondary compaction on an R angle area, and an integral compaction compression roller 13 is used for carrying out tertiary compaction on the integral surface to ensure compact.
4. The skin laying mode is as shown in fig. 5, after a plurality of groups of hat-shaped stringers on an integrated forming die 25 are laid, the ultrasonic cutting knife is used for processing the clean edge of the stringers, then the supporting structure 22 is placed in the hat-shaped groove, then the skin laying processing is carried out on the surface of the die by a filament laying machine, and the skin compaction is carried out by a compression roller 24 of the filament laying machine.
5. The curing bag-making process is as shown in fig. 6 and 7, the curing cover plate 26 is covered on the composite material wallboard preformed body (specifically comprising the cap stringer preformed body 20, the supporting structure 22 and the skin preformed body 23) containing the cap stringer, then the vacuum bag 27 is covered on the outer side of the curing cover plate 26 and the surface of the integrated mold 25, and is sealed and fixed on the cap stringer female mold platform through the sealing adhesive tape 28, and the vacuum is pumped through the vacuum nozzle of the vacuum bag for compaction and then is sent into the curing device for curing.
The above description is only exemplary of the preferred embodiments of the present invention, and is not intended to limit the present invention, and any modifications, equivalents, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. An integrated manufacturing process for hat-shaped stringer composite panels is characterized by comprising the following steps:
(1) stacking and compacting fewer layers of prepregs to prepare a prepreg thin-layer material sheet;
(2) extruding and bending the prepreg thin-layer material sheet to form a hat-shaped stringer pre-pressing material sheet;
(3) laying the hat-shaped stringer pre-pressing material sheet in a hat-shaped stringer female die in an integrated forming die, and respectively compacting the hat top, the hat waist, the hat edge and the R-angle transition region of the hat-shaped stringer by using multiple special-shaped press rollers;
(4) performing edge cleaning treatment on the compacted hat-shaped stringer;
(5) placing the support structure into the groove in the hat-shaped stringer, and laying the skin;
(6) and curing and forming after the covering is laid.
2. The integrated hat stringer composite panel manufacturing process according to claim 1, wherein no more than 8 layers of prepreg are used in step (1).
3. The integrated process of making a hat stringer composite panel according to claim 1, wherein in step (2) the sheet of prepreg laminate is heat treated.
4. The integrated hat stringer composite panel manufacturing process according to claim 1, wherein in step (2), the sheet of prepreg sheet is extruded and bent and then pre-shaped using a hat stringer pre-forming die, which is pre-heated.
5. The integrated process of making a hat stringer composite panel according to claim 4, wherein said pre-heating temperature of said hat stringer pre-forming mold is between 50 ℃ and 90 ℃.
6. The integrated cap stringer composite wall panel manufacturing process of claim 1, wherein said multiple profile rollers include a cap top roller, a cap waist roller, a cap skirt roller, an R-zone roller and an integral roller arranged in sequence.
7. The integrated hat stringer composite panel manufacturing process of claim 1, wherein step (3) is repeated until the prepreg reaches a set layer thickness to obtain a single hat stringer preform.
8. The integrated hat stringer composite panel manufacturing process of claim 1, wherein in step (3), the integrated molding die is heated.
9. The process of claim 8, wherein the heating temperature is 50 ℃ to 90 ℃.
10. The process of integrally manufacturing a hat stringer composite panel according to claim 1, wherein said support structure is made of a lightweight material including air cells, honeycomb or foam;
and (6) covering the composite material wallboard preformed body containing the hat-shaped stringer with a curing cover plate, arranging a vacuum bag between the curing cover plate and the integrated forming mold, sealing, vacuumizing, and compacting and curing.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011060714.3A CN112477190A (en) | 2020-09-30 | 2020-09-30 | Integrated manufacturing process for hat-shaped stringer composite material wallboard |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011060714.3A CN112477190A (en) | 2020-09-30 | 2020-09-30 | Integrated manufacturing process for hat-shaped stringer composite material wallboard |
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| Publication Number | Publication Date |
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| CN112477190A true CN112477190A (en) | 2021-03-12 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202011060714.3A Pending CN112477190A (en) | 2020-09-30 | 2020-09-30 | Integrated manufacturing process for hat-shaped stringer composite material wallboard |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113997468A (en) * | 2021-11-05 | 2022-02-01 | 中航沈飞民用飞机有限责任公司 | Reinforcement position and pressure control method for composite material reinforcement ring frame |
| CN114434827A (en) * | 2022-01-27 | 2022-05-06 | 西安交通大学 | Multi-station robot type automatic manufacturing method and device for special-shaped long purlin made of composite material |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1829595A (en) * | 2003-08-01 | 2006-09-06 | 阿利安特技术系统公司 | Apparatus and methods for forming composite stiffeners and reinforcing structures |
| CN106799851A (en) * | 2016-12-27 | 2017-06-06 | 中国商用飞机有限责任公司 | The moulding manufacture method of the composite hat Material Stiffened Panel based on piddler technology |
| CN108973172A (en) * | 2018-08-21 | 2018-12-11 | 南京航空航天大学 | The continuous pultrusion hot-press arrangement of Varying-thickness composite material hat stringer and forming method |
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2020
- 2020-09-30 CN CN202011060714.3A patent/CN112477190A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1829595A (en) * | 2003-08-01 | 2006-09-06 | 阿利安特技术系统公司 | Apparatus and methods for forming composite stiffeners and reinforcing structures |
| CN106799851A (en) * | 2016-12-27 | 2017-06-06 | 中国商用飞机有限责任公司 | The moulding manufacture method of the composite hat Material Stiffened Panel based on piddler technology |
| CN108973172A (en) * | 2018-08-21 | 2018-12-11 | 南京航空航天大学 | The continuous pultrusion hot-press arrangement of Varying-thickness composite material hat stringer and forming method |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113997468A (en) * | 2021-11-05 | 2022-02-01 | 中航沈飞民用飞机有限责任公司 | Reinforcement position and pressure control method for composite material reinforcement ring frame |
| CN114434827A (en) * | 2022-01-27 | 2022-05-06 | 西安交通大学 | Multi-station robot type automatic manufacturing method and device for special-shaped long purlin made of composite material |
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