CN115716544A - Pneumatic outer-surface composite cover plate and preparation method thereof - Google Patents

Abstract

The invention relates to a pneumatic profile composite cover plate and a preparation method thereof. The pneumatic outer-surface composite cover plate comprises a first tooling fabric layer, a second tooling fabric layer, a third tooling fabric layer and a fourth tooling fabric layer which are sequentially stacked. The pneumatic profile composite cover plate of the hat-shaped stringer stiffened co-curing wall plate provided by the invention can ensure that the surface quality of the pneumatic profile of the hat-shaped stringer stiffened co-curing wall plate is good. In addition, the pneumatic profile composite cover plate provided by the invention can be repeatedly used for many times, has strong operability and good stability, and can effectively reduce the cost of auxiliary materials.

Description

Pneumatic outer-surface composite cover plate and preparation method thereof

Technical Field

The invention relates to the technical field of preparation of stringer stiffened co-cured wallboards, in particular to a pneumatic profile composite cover plate and a preparation method thereof.

Background

The carbon fiber reinforced composite material has the advantages of high specific modulus and specific strength, corrosion resistance, high temperature resistance, fatigue resistance, good damping and shock absorption properties, strong designability, good dimensional stability and the like, and is widely applied to the fields of aviation, aerospace and the like. The use of composite materials in the civil aviation field has been increasing, with the weight percentage increasing from 4.5% for a300 to 53% for a350 and from 10% for B777 to 50% for B787. The reinforced structure has better torsion-resistant and bending-resistant rigid cap and is widely applied to the mechanism design. Carbon fiber reinforced M21 epoxy uni-directional tape prepreg of HEXCEL may be used as the body material for the stringers and skin. In addition, there may be a plurality of stringers on the skin, and the skin is generally wider and longer than the stringers for assembly with other components, so that there is skin at the lengthwise edges of the stringers.

A cover plate is not used on the existing pneumatic outer surface, and if the pneumatic outer surface does not use a hard cover plate, the problems of pits, poor skin surface quality, unqualified thickness and the like can occur in the bottom area of the long truss cap with the cured pneumatic outer surface of the product (as shown in figure 2). The product quality is seriously influenced, and the production efficiency is reduced.

Disclosure of Invention

In view of the above disadvantages of the prior art, the present invention provides a pneumatic profiled composite cover plate and a method for making the same, which are used to solve the problems of the prior art.

In order to achieve the above and other related objects, an aspect of the present invention provides a pneumatic outer surface composite cover plate, including a first tooling fabric layer, a second tooling fabric layer, a third tooling fabric layer and a fourth tooling fabric layer, which are sequentially stacked; the content of resin in the first tooling fabric layer is 45% -50%; the content of resin in the second tooling fabric layer is 35-40%; the content of resin in the third tooling fabric layer is 35-40%; the content of the resin in the fourth tooling fabric layer is 45-50%.

In some embodiments of the invention, the ply angle of the first tooling fabric layer is 0, +90, or-90.

In some embodiments of the invention, the first tooling fabric layer has a thickness of 0.2mm to 0.3mm.

In some embodiments of the invention, the ply angle of the second tooling fabric layer is +45 ° or-45 °.

In some embodiments of the invention, the second tooling fabric layer has a thickness of 0.6mm to 0.7mm.

In some embodiments of the invention, the ply angle of the third tooling fabric layer is +45 ° or-45 °.

In some embodiments of the invention, the third tooling fabric layer has a thickness of 0.6mm to 0.7mm.

In some embodiments of the invention, the ply angle of the fourth tooling fabric layer is 0, +90, or-90.

In some embodiments of the invention, the fourth layer of tooling fabric has a thickness of 0.2mm to 0.3mm.

The invention also provides a preparation method of the pneumatic profile composite cover plate, which comprises the following steps:

s1: brushing a release agent on a cover plate forming tool, paving a layer of first tool fabric prepreg on the surface of the cover plate forming tool after the release agent is completely dried, and performing pre-compaction after paving to obtain a first pre-compacted tool fabric;

s2: paving and pasting a second pre-compaction tool fabric prepreg on the first pre-compaction tool fabric provided in the step S1, and pre-compacting after paving and pasting to obtain a second pre-compaction tool fabric;

s3, paving and adhering a third pre-compaction tool fabric prepreg on the second pre-compaction tool fabric provided in the step S2, and pre-compacting after paving and adhering are finished to obtain a third pre-compaction tool fabric;

s4: paving and pasting a fourth tool fabric prepreg on the third pre-compacted tool fabric provided in the step S3, and pre-compacting after paving and pasting to obtain a fourth pre-compacted tool fabric;

s5: putting each layer of pre-compacted tooling fabric into a vacuum bag for sealing;

s6: and (3) performing precuring, removing the bag and demoulding after precuring is finished, and performing postcuring to obtain the pneumatic profile composite cover plate.

In some embodiments of the invention, in step S1, in the pre-compaction process, the compaction time is not less than 15min, and the compaction vacuum is less than-80 KPa.

In some embodiments of the invention, in step S1, the content of the resin in the first tooling fabric prepreg is 45% to 50%.

In some embodiments of the invention, in step S1, the ply angle of the first tooling fabric prepreg is 0 °, +90 °, or-90 °.

In some embodiments of the invention, in the pre-compaction process of step S2, the compaction time is not less than 15min, and the compaction vacuum degree is less than-80 KPa.

In some embodiments of the invention, in step S2, the resin content in the second tooling fabric prepreg is 35% to 40%.

In some embodiments of the invention, in step S2, the ply angle of the second tooling fabric prepreg is +45 ° or-45 °.

In some embodiments of the invention, in step S3, in the pre-compaction process, the compaction time is not less than 15min, and the compaction vacuum degree is less than-80 KPa.

In some embodiments of the present invention, in the step S3, the content of the resin in the third tooling fabric prepreg is 35% to 40%.

In some embodiments of the invention, in step S3, the ply angle of the third tooling fabric prepreg is +45 ° or-45 °.

In some embodiments of the invention, in step S4, in the pre-compaction process, the compaction time is not less than 15min, and the compaction vacuum degree is less than-80 KPa.

In some embodiments of the invention, in step S4, the resin content in the fourth tooling fabric prepreg is 45% to 50%.

In some embodiments of the invention, in step S4, the ply angle of the fourth tooling fabric prepreg is 0 °, +90 °, or-90 °.

In some embodiments of the present invention, in step S6, the pre-curing pressure is 0.4MPa to 0.7MPa, the whole curing process is vacuumized, the temperature is raised to 60 ℃ to 63 ℃ at a temperature raising rate of 0.5 ℃/min to 1.0 ℃/min, and the temperature is maintained for 16 to 17 hours.

In some embodiments of the invention, the post-cure process is pressure-free, vacuum-free; heating to 60-63 ℃ at the speed of 1-2 ℃/min, heating to 200-203 ℃ at the speed of 0.3-0.5 ℃/min, preserving heat for 15-20 min, cooling to 190 ℃ at the speed of 1-2 ℃/min, preserving heat for 8 hours, cooling to room temperature at the speed of no more than 3.0 ℃/min, and finishing curing.

In another aspect, the invention provides the use of the aerodynamic profile composite cover plate of the invention in the preparation of stringer stiffened co-cured siding.

The invention provides a processing technology of a stringer stiffened co-cured wallboard, which comprises the following steps:

1) Assembling the inner core mold and the flexible rubber core mold to obtain an inner core mold and flexible rubber core mold assembly;

2) Turning the net-size stringer into a female die forming tool; the net stringer comprises a stringer crown, two symmetrically distributed stringer waists, and two symmetrically distributed stringer flanges;

3) Placing the inner core mould and the flexible rubber core mould assembly in the step 1) into an inner cavity of the net-size stringer;

4) Filling the twill strips into the residual gaps of the inner cavity of the stringer by utilizing laser projection positioning, sleeving a temporary vacuum bag on the outer surface of the stringer and compacting, wherein the cap bottom of the assembled rubber core mold, the twill strips, the stringer edge strips and the skin paving area of the female mold forming tool are parallel and level;

5) The end part of the net-size stringer is provided with a hard cover plate; a cover plate groove matched with the hard cover plate is formed in the female die forming tool; arranging the hard cover plate in the cover plate groove;

6) Skin spreading and silk spreading are carried out on a skin spreading and pasting area of the female die forming tool, a fringe area of the stringer and a cap bottom area of the flexible rubber core die, skin is formed after silk spreading is finished, and the inner core die is taken out;

7) Fixing the pneumatic profile composite cover plate according to any one of claims 1 to 5 on the outer surface of the skin, wherein an outer vacuum bag is arranged on the pneumatic profile composite cover plate, the outer vacuum bag and the pneumatic profile composite cover plate are sealed by a first sealing rubber strip, and the tubular vacuum bag is communicated with the outer vacuum bag;

8) And demolding after curing.

Compared with the prior art, the invention has the following beneficial effects:

the pneumatic profile composite cover plate of the hat-shaped stringer stiffened co-cured wallboard provided by the invention can ensure that the pneumatic profile surface quality of the hat-shaped stringer stiffened co-cured wallboard is good. In addition, the pneumatic profile composite cover plate provided by the invention can be repeatedly used for many times, has strong operability and good stability, and can effectively reduce the cost of auxiliary materials.

According to the processing technology of the hat-shaped stringer stiffened wall plate, the tubular vacuum bag in the rubber core mould is communicated with the external vacuum bag, so that the curing pressure in the inner cavity of the stringer is consistent with that outside the skin, and the good surface quality of the inner cavity of the stringer and the uniform thickness of the stringer can be guaranteed.

Drawings

Fig. 1 is a schematic view of a laminated structure of a cover plate of a pneumatic profile composite material provided by the present invention.

FIG. 2 is a schematic diagram of the problem of unqualified aerodynamic profile of the co-cured hat-shaped stringer stiffened panel (skin dimpling, thickness out-of-tolerance) to be solved by the present invention.

FIG. 3 is a cross-sectional view of a hat stringer stiffened co-cured panel of the present invention.

FIG. 4 is a schematic view of a co-curing hat stiffened panel forming tool provided by the present invention.

FIG. 5 is a schematic view of a cap stringer end cover plate and tooling provided in accordance with the present invention.

FIG. 6 is a cross-sectional view of a cured hat stringer stiffened panel made by the skin filament laying process of the present invention.

FIG. 7 is a schematic view of the final envelope provided by the present invention.

Fig. 8 is a schematic structural diagram of a hard cover plate provided by the present invention.

Fig. 9 is a schematic view of a panel of comparative example 1 without using the composite cover sheet provided by the present invention. FIG. 9a is a skin aerodynamic surface and FIG. 9b is a stringer surface.

Fig. 10 is a real view of the appearance of the wall panel using the composite cover plate provided by the invention in example 2. FIG. 10a is the aerodynamic surface of the skin and FIG. 10b is the stringer surface.

Fig. 11 is an ultrasonic inspection of a panel made according to the present invention.

FIG. 12 is a schematic drawing of the thickness measurement points of the wallboard made according to the present invention.

Description of the drawings:

1. profiled tooling stringer top area

2. R-angle area of long truss hat top of forming tool

3. Long purlin cap lumbar region of shaping frock

4. Stringer tape area of forming tool

5. Skin paving area

6. Cover plate groove

7. Long purlin outer rubber mandrel recess of shaping frock

8. Forming tool sealing rubber strip area groove

9. Hard cover plate

91. Rubber core mould attaching part

911. First bonding part

912. Second bonding part

92. Retainer

93. R region of cover plate

94. Position fixing hole

10. Female die forming tool

11. Stringer tops

12. Long purlin waist of hat

13. Stringer tape

14. Covering skin

15. Twill strip

16. Flexible rubber core mould

17. Pneumatic external surface composite material cover plate

171. First frock fabric layer

172. Second tooling fabric layer

173. Third frock fabric layer

174. Fourth tooling fabric layer

18. Inner core mould

19. Metal chain

20. First joint strip

21. Long purlin oblique angle area of shaping frock

22. External vacuum bag

23. Tubular vacuum bag

24. Automatic spreading machine compression roller

Detailed Description

In the description of the present invention, it should be noted that the structures, ratios, sizes, and the like shown in the drawings attached to the present specification are only used for matching with the disclosure of the specification, so as to be understood and read by those skilled in the art, and are not used to limit the conditions that the present invention can be implemented, so that the present invention has no technical essence, and any structural modification, ratio relationship change, or size adjustment should still fall within the scope of the technical disclosure of the present invention without affecting the function and the achievable purpose of the present invention. While the terms "central," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like refer to orientations and positional relationships illustrated in the drawings, which are used for convenience in describing the invention and to simplify the description, and do not indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be considered limiting of the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In addition, in the description of the present invention, "a plurality" means two or more unless otherwise specified.

A large number of tests prove that the pneumatic outer surface composite cover plate is applied to the processing technology of the stringer stiffened co-cured wallboard, and the good surface quality of the pneumatic outer surface of the hat-shaped stringer stiffened co-cured wallboard can be ensured. In addition, the composite cover plate provided by the invention can be repeatedly used for many times, has strong operability and good stability, and can effectively reduce the cost of auxiliary materials. On this basis, the present application has been completed.

In one aspect, the invention provides an aerodynamic profile composite cover plate, as shown in fig. 1, the aerodynamic profile composite cover plate includes a first tooling fabric layer 171, a second tooling fabric layer 172, a third tooling fabric layer 173 and a fourth tooling fabric layer 174 which are sequentially stacked; the resin content in the first tooling fabric layer 171 may be 45% to 50%, 45% to 48%, or 48% to 50%, etc. The resin content in the second tooling fabric layer 172 can be 35% -40%, 35% -38%, or 38% -40%, etc. The content of the resin in the third tooling fabric layer 173 may be 35% to 40%, 35% to 38%, 38% to 40%, or the like. The content of the resin in the fourth tooling fabric layer 174 may be 45% to 50%, 45% to 48%, or 48% to 50%, etc.

In the pneumatic profiled composite cover plate provided by the present invention, in general, the ply angle of the first tooling fabric layer 171 is 0 °, +90 °, or-90 °. Generally, the 0 ° direction of the component is defined as the 0 ° direction of the cover plate based on the space coordinate system of the component. The thickness of the first tooling fabric layer 171 may be 0.2mm to 0.3mm, 0.2mm to 0.23mm, or 0.23mm to 0.3mm, etc. The resin in the first tooling fabric layer 171 may be, for example, epoxy resin, and the other components of the first tooling fabric layer 171 include carbon fiber fabric in addition to the resin.

In the pneumatic profile composite cover plate provided by the invention, the layering angle of the second tooling fabric layer 172 is +45 degrees or-45 degrees. Generally, the 0 ° direction of the component is defined as the 0 ° direction of the cover plate based on the space coordinate system of the component. Where +45 means 45 clockwise offset from the 0 orientation of the part. By-45 is meant a 45 deg. counterclockwise deflection in the direction of 0 deg. of the part. The thickness of the second tooling fabric layer 172 may be 0.6mm to 0.7mm, 0.6mm to 0.65mm, or 0.65mm to 0.7mm, etc. The resin in the second tooling fabric layer 172 may be, for example, epoxy resin, and the other components of the second tooling fabric layer 172 include carbon fiber fabrics besides the resin.

In the pneumatic profile composite cover plate provided by the invention, the layer laying angle of the third tooling fabric layer 173 is +45 degrees or-45 degrees. Wherein 45 is meant to mean a 45 clockwise deflection in the direction of 0 of the part. By-45 is meant a counter-clockwise deflection of 45 in the direction of 0 of the part. The thickness of the third tooling fabric layer 173 may be 0.6mm to 0.7mm, 0.6mm to 0.65mm, or 0.65mm to 0.7mm, etc. The resin in the third tooling fabric layer 173 may be, for example, epoxy resin, and the other components of the third tooling fabric layer 173 include carbon fiber fabric in addition to the resin. The reason why the second tooling fabric layer and the third tooling fabric layer are laid in 2 layers is that if the thickness is too thick, for example, the laying thickness exceeds 1mm, gas is generated in the laying process, and the gas in the layers cannot be discharged, so that dense pores or layering of the cover plate can be caused.

In the cover plate of the pneumatic profile composite material provided by the invention, the ply angle of the fourth tooling fabric layer 174 is 0 degree, +90 degrees or-90 degrees. Wherein 0 ° means that the 0 ° direction of the component is defined as the 0 ° direction of the cover plate based on the space coordinate system of the component. By +90 is meant a 90 clockwise deflection in the direction of 0 of the part and by-90 is meant a 90 counterclockwise deflection in the direction of 0 of the part. The thickness of the fourth tooling fabric layer 174 may be 0.2mm to 0.3mm, 0.2mm to 0.23mm, or 0.23mm to 0.3mm, etc. The resin in the fourth woven fabric layer 174 may be, for example, epoxy resin, and the other components of the fourth woven fabric layer 174 include carbon fiber fabrics in addition to the resin.

The first tooling fabric layer 171, the second tooling fabric layer 172, the third tooling fabric layer 173 and the fourth tooling fabric layer 174 are laid according to the angles, so that the cover plate is not deformed obviously after being cured and demoulded and is not deformed after being used for a long time. The first tooling fabric layer 171, the second tooling fabric layer 172, the third tooling fabric layer 173 and the fourth tooling fabric layer 174 are laid according to the above thicknesses, so that the cover plate has the advantages of ensuring good quality of the inner surface and the outer surface and the inner quality, and having no defects such as pores or poor glue and the like.

The invention also provides a preparation method of the pneumatic profile composite cover plate, which comprises the following steps:

s1: brushing a release agent on a cover plate forming tool, paving a layer of first tool fabric prepreg on the surface of the cover plate forming tool after the release agent is completely dried, and performing pre-compaction after paving to obtain a first pre-compacted tool fabric;

s2: paving and pasting a second pre-compaction tool fabric prepreg on the first pre-compaction tool fabric provided in the step S1, and pre-compacting after paving and pasting to obtain a second pre-compaction tool fabric;

s3, paving and adhering a third pre-compaction tool fabric prepreg on the second pre-compaction tool fabric provided in the step S2, and pre-compacting after paving and adhering are finished to obtain a third pre-compaction tool fabric;

s4: paving and pasting a fourth tool fabric prepreg on the third pre-compacted tool fabric provided in the step S3, and pre-compacting after paving and pasting to obtain a fourth pre-compacted tool fabric;

s5: putting each layer of pre-compacted tooling fabric into a vacuum bag for sealing;

s6: and (3) performing precuring, removing the bag and demoulding after precuring is finished, and performing postcuring to obtain the pneumatic profile composite cover plate 17.

In the preparation method of the pneumatic profiled composite cover plate, the step S1 is to brush a release agent on a cover plate forming tool, lay a layer of first tool fabric prepreg on the surface of the cover plate forming tool after the release agent is completely dried, and perform pre-compaction after the laying is finished to obtain a first pre-compacted tool fabric. Specifically, the content of the resin in the laid first tooling fabric prepreg can be 45% -50%, 45% -48%, or 48% -50%, and the like. The ply angle is 0 degrees, +90 degrees or-90 degrees, the explanation of the ply angle is the same as before, the temporary vacuum bag is sealed and precompacted after the first tooling fabric prepreg is laid, the compacting time is not less than 15min, and the compacting vacuum degree is lower than-80 KPa. Preferably, the compaction time is 30min. The compaction vacuum degree is-95 KPa. In some embodiments, the first tooling fabric prepreg was purchased from GE15/W-3021, guangwei.

In the preparation method of the pneumatic outer-profile composite cover plate, step S2 is to lay a second pre-compaction tool fabric prepreg on the first pre-compaction tool fabric provided in step S1, and pre-compaction is performed after laying is completed to obtain a second pre-compaction tool fabric. Specifically, the content of the resin in the laid second tooling fabric prepreg can be 35% -40%, 35% -38%, 38% -40% or the like. And the ply angle is +45 degrees or-45 degrees, the explanation of the ply angle is the same as that before the ply angle is explained, the air guide is noticed in the ply process, the temporary vacuum bag is sealed for pre-compaction after the second tooling fabric prepreg is laid, the compaction time is not less than 15min, and the compaction vacuum degree is lower than-80 KPa. Preferably, the compaction time is 30min. The compaction vacuum degree is-95 KPa. In some embodiments, the second tooling fabric prepreg was purchased from GE15/W-7021, guangwei Kogyo.

In the preparation method of the pneumatic outer-profile composite cover plate, step S3 is to lay a third pre-compaction fixture fabric prepreg on the second pre-compaction fixture fabric provided in step S2, and pre-compact the second pre-compaction fixture fabric after laying is finished to obtain a third pre-compaction fixture fabric. Specifically, the content of the resin in the laid third tooling fabric prepreg can be 35% -40%, 35% -38%, 38% -40% or the like. And (3) the ply angle is +45 degrees or-45 degrees, the air guide is noticed in the ply process, the explanation of the ply angle is the same as that before, the temporary vacuum bag is sealed for pre-compaction after the third tooling fabric prepreg is laid, the compaction time is not less than 15min, and the compaction vacuum degree is lower than-80 KPa. Preferably, the compaction time is 30min. The compaction vacuum degree is-95 KPa. In some embodiments, the third tooling fabric prepreg was purchased from GE15/W-7021, guangwei Kogyo.

In the preparation method of the pneumatic outer-shaped surface composite cover plate, step S4 is to lay a fourth pre-compaction tool fabric prepreg on the third pre-compaction tool fabric provided in step S3, and pre-compaction is performed after laying is completed to obtain a fourth pre-compaction tool fabric. Specifically, the content of the resin in the laid fourth tooling fabric prepreg can be 45% -50%, 45% -48%, 48% -50% or the like. The layering angle is 0 degrees, +90 degrees or-90 degrees, the explanation of the layering angle is the same as before, the temporary vacuum bag is sealed and pre-compacted after the fourth tooling fabric prepreg is paved, the compacting time is not less than 15min, and the compacting vacuum degree is lower than-80 KPa. Preferably, the compaction time is 30min. The compaction vacuum degree is-95 KPa. In some embodiments, the fourth tooling fabric prepreg was purchased from GE15/W-3021, guangwei Kogyo.

In the preparation method of the pneumatic external composite cover plate, step S5 is to place each layer of pre-compacted tooling fabric into a vacuum bag for sealing. The air guide is needed in the bag sealing process, the air guide wires are placed in the allowance area of the part and contact with the edge air guide fibers, the surface of the part can be a porous isolation film or a nonporous isolation film, the selection of the isolation film is determined according to the size and the shape of an actual product, and the porous isolation film is generally recommended for large-size parts.

In the preparation method of the pneumatic outer-shaped surface composite cover plate, step S6 is to perform pre-curing, remove the bag and demould after the pre-curing is finished, and obtain the pneumatic outer-shaped surface composite cover plate 17 after post-curing. The invention adopts twice curing process, which can effectively prevent the cover plate from deforming after curing and demoulding. Specifically, the precuring pressure may be 0.4 to 0.7MPa, 0.4 to 0.6MPa, or 0.6 to 0.7MPa or the like. Vacuumizing in the whole curing process, heating to 60-63 ℃ at the heating rate of 0.5-1.0 ℃/min, preserving heat for 16-17 hours, cooling to room temperature at the cooling rate of not more than 3.0 ℃/min, removing the bag after precuring is finished, drilling a positioning hole by using a drilling jig, and demoulding after drilling is finished. And placing the cover plate on the surface of the forming tool to perform a post-curing process, wherein the post-curing process has no pressure and no vacuum. Heating to 60-63 ℃ at 1-2 ℃/min, 1-1.5 ℃/min, or 1.5-2 ℃/min, then heating to 200-203 ℃ at 0.3-0.5 ℃/min, 0.3-0.4 ℃/min, or 0.4-0.5 ℃/min, keeping the temperature for 15-20 min, cooling to 190 ℃ at 1-2 ℃/min, 1-1.5 ℃/min, or 1.5-2 ℃/min, keeping the temperature for 8 hours, cooling to room temperature at a cooling rate of no more than 3.0 ℃/min, and finishing the curing.

The thickness of the cover plate after the secondary curing process is 1.6 mm-2 mm. The composite cover plate can ensure that the pneumatic profile of the hat-shaped stringer stiffened co-cured wallboard receives uniform pressure in the curing process, so that the surface quality of the pneumatic profile can be ensured to be good.

The invention also provides application of the pneumatic profile composite cover plate in preparation of stringer stiffened co-cured wallboards.

The invention also provides a processing technology of the stringer stiffened co-cured wallboard, which comprises the following steps:

1) Assembling the inner core mold 18 and the flexible rubber core mold 16 to obtain an inner core mold and flexible rubber core mold assembly;

2) Turning the net-size stringer into a female die forming tool 10; the net stringer comprises a stringer crown 11, two stringer waists 12 symmetrically distributed, and two stringer flanges 13 symmetrically distributed;

3) Placing the inner core mould and the flexible rubber core mould assembly in the step 1) into an inner cavity of the net-size stringer;

4) Utilizing laser projection positioning to fill the twill strip 15 in the residual gap of the inner cavity of the stringer, sleeving a temporary vacuum bag on the outer surface of the stringer and compacting, wherein the cap bottom of the assembled rubber core mold, the twill strip 15, the stringer flange strip 13 and the skin paving area 5 of the female mold forming tool 10 are parallel and level;

5) The end part of the net-size stringer is provided with a hard cover plate 9; a cover plate groove 6 matched with the hard cover plate 9 is formed in the female die forming tool 10; the hard cover plate 9 is arranged in the cover plate groove 6;

6) Performing skin 14 filament laying on a skin laying area 5, a stringer marginal strip area and a cap bottom area of a flexible rubber core mold 16 of the female mold forming tool 10, forming a skin 14 after filament laying is completed, and taking out an inner core mold 18;

7) The pneumatic outer-surface composite cover plate 17 is fixed on the outer surface of the skin 14, an external vacuum bag 22 is arranged on the pneumatic outer-surface composite cover plate 17, the external vacuum bag 22 and the pneumatic outer-surface composite cover plate 17 are sealed through a first sealing rubber strip 20, and a tubular vacuum bag 23 is communicated with the external vacuum bag 22;

8) And demolding after curing.

In the processing technology of the stringer stiffened co-cured wallboard provided by the invention, step 1) is to assemble an inner core mould 18 and a flexible rubber core mould 16 to obtain an inner core mould and a flexible rubber core mould assembly. The preparation method of the inner core mold and the flexible rubber core mold component comprises the following steps: placing the inner core mold 18 within a tubular vacuum bag 23; and placing the tubular vacuum bag 23 into the rubber inner cavity of the flexible rubber core mold 16 to obtain an inner core mold and flexible rubber core mold assembly.

In the preparation method of the inner core mold and flexible rubber core mold assembly provided by the invention, the inner core mold 18 is filled with liquid rubber which is mixed according to the proportion requirement, and a metal chain 19 is added in the liquid rubber to enhance the rigidity of the inner core mold 18.

In the processing technology of the stringer stiffened co-cured wallboard provided by the invention, step 2) is to turn the net-size stringer into a female die forming tool 10. Wherein the net stringer is obtained by laying and cutting the stringer. Specifically, the preparation of the net-size stringer is accomplished by hand lay-up of the stringer and ultrasonic automated cutting. Further, as shown in FIG. 3, the net-size stringer includes a top stringer 11, two symmetrically disposed waist stringer webs 12, and two symmetrically disposed stringer flanges 13. Two stringer waists 12 are respectively connected to both side edges of the stringer tops 11. Stringer tape 13 is connected to stringer waists 12 to form a stringer that is hat-shaped in cross-section. Specifically, a stringer crown 11 and two stringer waists 12 enclose the interior cavity of the stringer. As shown in fig. 4, the female die forming tool 10 includes a forming tool stringer top region 1, two forming tool stringer top waist regions 3, and two forming tool stringer flange regions 4, and the forming tool stringer top region 1 and the two forming tool stringer top waist regions 3 are connected through a forming tool stringer top R corner region 2. The forming tooling stringer top region 1, the forming tooling stringer top R corner region 2 are connected and the two forming tooling stringer top waist regions 3 form stringer receiving slots. Wherein, long purlin crest 11 aims at long purlin crest region 1 of shaping frock, long purlin hat waist 12 aims at long purlin hat waist region 3 of shaping frock, long purlin flange 13 is aimed at long purlin flange region 4 of shaping frock can guarantee that long purlin equipment position is accurate.

In the processing technology of the stringer stiffened co-cured wallboard provided by the invention, the step 3) is to place the inner core mould and the flexible rubber core mould assembly into an inner cavity of a net-size stringer. The inner core mold and the flexible rubber core mold component can be prepared by the preparation method of the inner core mold and the flexible rubber core mold component. During the insertion process, the assembled inner core mold and flexible rubber core mold assembly can be positioned and placed in the inner cavity of the stringer by utilizing the grooves.

In the processing technology of the stringer stiffened co-cured wallboard provided by the invention, step 4) is to fill the remaining gap of the inner cavity of the stringer with the twister strip 15 by utilizing laser projection positioning, seal a temporary vacuum bag, press the stringer and compact the stringer, and ensure that the inner cavities of the flexible rubber core mould 16 and the stringer are well matched. The cap bottom of the assembled rubber core mold, the twill strip 15, the stringer tape 13, and the skin-laying area 5 of the female mold forming tool 10 are flush.

In the processing technology of the stringer stiffened co-cured wallboard provided by the invention, as shown in fig. 5, step 5) is that a hard cover plate 9 is arranged at the end part of the net-size stringer. The rigid decking 9 may be, for example, metal decking, the material of which is selected taking into account a material having a coefficient of thermal expansion close to that of the stringer stiffened co-cured panel. For example, the steel cover plate may be made of Invar steel, and more specifically, the Invar steel may be made of Invar steel. A cover plate groove 6 matched with the hard cover plate 9 is formed in the female die forming tool 10; the hard cover plate 9 is arranged in the cover plate groove 6. As shown in fig. 8, in an embodiment, the hard cover plate 9 includes a rubber core attaching portion 91 including a first attaching portion 911 and a second attaching portion 912 which are connected, two sides of the rubber core attaching portion are respectively provided with a retaining portion 92, and each retaining portion is respectively provided with a retaining hole 94; each of the retainers 92 is connected to the rubber core attaching portion 91 via a cover R region 93; the thicknesses of the first bonding portions 911 are equal; the thickness of the second attaching portion 912 is gradually reduced.

In the processing technology of the stringer stiffened co-cured wallboard provided by the invention, as shown in fig. 6, step 6) is to perform skin 14 filament laying on a skin laying area 5 of the female die forming tool 10, a stringer area and a cap bottom area of the flexible rubber core die 16, form a skin 14 after filament laying is finished, and take out the inner core die 18. Wherein the skin 14 is laid on an automatic laying machine, for example. The spreading angle is the angle defined in the drawing, and the angle may be [ -45/45/45/90/-45/0/-45/90/45/45/-45], for example. The wire laying gap meets the requirements of design drawings. The spreading gap can be, for example, ≦ 1mm.

In the processing technology of the stringer stiffened co-cured wallboard provided by the invention, as shown in fig. 7, step 7) is to fix a pneumatic profile composite cover plate 17 on the outer surface of the skin 14. The fixing method can be, for example, positioning and assembling by using pins. The outer vacuum bag 22 is sealed with the pneumatic outer profile composite cover plate 17 by a first sealing rubber strip 20, specifically, the first sealing rubber strip 20 is adhered in the tool bag sealing area. An external vacuum bag 22 is provided on the pneumatic profile cover plate 17, communicating the tubular vacuum bag 23 with the external vacuum bag 22. The curing pressure is maintained the same outside the outer vacuum bag 22 as the rubber core cavity during the curing process. Can ensure good surface quality of the inner cavity of the stringer and uniform thickness of the stringer.

Further, the pneumatic outer profile composite cover plate is the pneumatic outer profile composite cover plate provided by the first aspect of the invention.

In the processing technology of the stringer stiffened co-cured wallboard provided by the invention, step 8) is demoulding after curing. Specifically, the step of demolding after curing comprises the following steps: respectively demoulding the hard cover plate 9 and the pneumatic outer profile composite cover plate 17, taking out the first auxiliary material in the inner cavity of the flexible rubber core mould 16, vacuum-sealing two ends of the flexible rubber core mould 16, vacuumizing to deform the flexible rubber core mould 16, then taking out the flexible rubber core mould 16 from the inner cavity of the stringer in a manual dragging mode, and taking out the second auxiliary material after the flexible rubber core mould 16 is taken out.

In step 8) of the present invention, in particular, the first auxiliary material includes an outer vacuum bag 22, a first sealing rubber strip 20 and the like.

In step 8), a second auxiliary material is further removed from the inner cavity of the flexible rubber core mold 16, wherein the second auxiliary material comprises a tubular vacuum bag 23, and specifically, the auxiliary material in the flexible rubber core mold 16 is separated from the inner cavity of the flexible rubber core mold 16 through multiple rotations, and then the auxiliary material is separated through dragging.

In step 8), the vacuum sealing of the two ends of the flexible rubber core mold 16 includes sealing one end of the flexible rubber core mold 16 with a second sealing rubber strip and a vacuum bag, sealing the other end of the flexible rubber core mold 16 with a third sealing rubber strip and a vacuum bag, ventilating and sealing the bag, vacuumizing the interior of the flexible rubber core mold 16 by a vacuum nozzle base to deform the flexible rubber core mold 16 to 40% -50%, preferably 50% of the original size, then releasing the flexible rubber core mold 16 from the inner cavity of the stringer in a manual dragging mode, and taking out third auxiliary materials at the two ends after the flexible rubber core mold 16 is released. The third auxiliary material comprises a second sealing rubber strip, a third sealing rubber strip, a vacuum bag ventilation sealing bag and the like.

The following examples are provided to further illustrate the advantageous effects of the present invention.

In order to make the purpose, technical solutions and advantageous technical effects of the present invention clearer, the present invention is described in further detail below with reference to examples. However, it should be understood that the embodiments of the present invention are only for explaining the present invention and not for limiting the present invention, and the embodiments of the present invention are not limited to the embodiments given in the specification. The examples were prepared under conventional conditions or conditions recommended by the material suppliers without specifying specific experimental conditions or operating conditions.

Furthermore, it is to be understood that one or more method steps mentioned in the present invention does not exclude that other method steps may also be present before or after the combined steps or that other method steps may also be inserted between these explicitly mentioned steps, unless otherwise indicated; it is also to be understood that a combined connection between one or more devices/apparatus as referred to in the present application does not exclude that further devices/apparatus may be present before or after the combined device/apparatus or that further devices/apparatus may be interposed between two devices/apparatus explicitly referred to, unless otherwise indicated. Moreover, unless otherwise indicated, the numbering of the various method steps is merely a convenient tool for identifying the various method steps, and is not intended to limit the order in which the method steps are arranged or the scope of the invention in which the invention may be practiced, and changes or modifications in the relative relationship may be made without substantially changing the technical content.

In the following examples, reagents, materials and instruments used are commercially available unless otherwise specified.

Example 1

1. Brushing a release agent on a cover plate forming tool, paving a layer of tool fabric prepreg with the resin content of 45% on the surface of the tool after the release agent is completely dried, wherein the paving angle is 0 degrees, the nominal thickness of the tool prepreg fabric is 0.23mm, sealing a temporary vacuum bag for pre-compaction after the layer of prepreg is paved, the compaction time is not less than 15min, and the compaction vacuum degree is lower than-80 KPa;

2. paving and pasting a second layer and a third layer which are tooling fabric prepregs with the resin content of 38%, wherein the paving angle is 45 degrees, the nominal thickness of the tooling prepreg fabric is 0.65mm, air conduction is required in the paving process, each layer needs to be pre-compacted once after being paved, the compacting time is not less than 15min, and the compacting vacuum degree is lower than-80 KPa;

3. paving and pasting a fourth layer of tool fabric prepreg with the resin content of 45%, wherein the paving angle is 0 degrees, the nominal thickness of the tool prepreg fabric is 0.23mm, sealing a temporary vacuum bag for pre-compaction after the fourth layer is paved and pasted, the compaction time is not less than 15min, and the compaction vacuum degree is lower than-80 KPa;

4. and sealing the final vacuum bag, paying attention to air guide in the bag sealing process, placing an air guide wire in the part allowance area, contacting edge air guide fibers, selecting a porous isolation film or a nonporous isolation film on the surface, determining the selection of the isolation film according to the size and the shape of an actual product, and generally proposing the use of the porous isolation film for large-size parts.

5. And curing, wherein the cover plate curing is a secondary curing process which comprises pre-curing and post-curing processes, the pre-curing pressure is 0.6Mpa, the whole curing process is vacuumized, the temperature is increased to 60 ℃ at the temperature rise rate of 0.5 ℃/min, and the temperature is kept for 16 hours.

6. Removing the bag after the precuring is finished, drilling a positioning hole by using a drilling jig, and demoulding after the drilling is finished;

7. and (3) placing the cover plate on the surface of the forming tool to carry out a post-curing process, wherein the post-curing process has no pressure or vacuum, the temperature is raised to 60 ℃ at the speed of 1.5 ℃/min, then the temperature is raised to 200 ℃ at the speed of 0.5 ℃/min, the temperature is kept for 15min, the temperature is lowered to 190 ℃ at the speed of 1.5 ℃/min, the temperature is kept for 8 hours, the temperature is lowered to 60 ℃ at the speed of 1.5 ℃/min, and the curing is finished.

Example 2

1. Liquid rubber mixed according to the proportion requirement is poured into the inner core mold 18 forming tool, and a metal chain 19 is added into the liquid rubber to enhance the rigidity of the inner core mold 18. Placing the inner core mold 18 within a tubular vacuum bag 23; the tubular vacuum bag 23 is placed into the rubber inner cavity of the flexible rubber core mold 16 to obtain an inner core mold and a flexible rubber core mold assembly.

2. The preparation of the net-size stringer is finished through manual paving and automatic ultrasonic cutting, the net-size stringer is turned into a female die forming tool 10, the long stringer top 11 is aligned with the long stringer top area 1 of the forming tool, the long stringer top 12 is aligned with the cap waist area of the female die tool, and the long stringer edge strip 13 is aligned with the edge strip area of the female die tool, so that the accuracy of the long stringer assembling position can be guaranteed. As shown in fig. 3 and 4.

3. The assembled flexible rubber core 16 is positioned and placed into the stringer internal cavity by the forming tool stringer external rubber core groove 7.

4. Positioning by laser projection, assembling the twiddle strips 15 into the stringer inner cavity, sealing a temporary vacuum bag and compacting to ensure that the rubber core mold and the stringer inner cavity are perfectly matched, and after the assembly is finished, ensuring that the cap bottom part of the rubber core mold is flush with the plane of the twiddle strips 15, the edge strip part of the stringer and a skin paving area 5 of a forming female mold tool in a twisting manner;

5. and assembling a hard cover plate 9 in a groove of the stringer end female die forming tool 10. The structure of the hard cover plate 9 is shown in fig. 8.

6. As shown in fig. 6, a press roll 24 of an automatic filament paving machine is used for conducting filament paving on a skin area of the assembled female die forming tool 10, a stringer marginal strip area and a cap bottom area of the rubber core die 16, filament paving is conducted at a filament paving angle according to an angle specified by a drawing, filament paving gaps meet the design drawing requirements, the skin 14 is formed after filament paving is completed, and the inner core die 18 is taken out after filament paving is completed.

7. Referring to fig. 7, the pneumatic outer-profile composite cover plate 17 prepared in example 1 is assembled on the outer surface of the skin 14 by pin positioning, a first sealing rubber strip is adhered in the tool bag sealing area, and the rubber core mold inner tubular vacuum bag 23 is communicated with the outer vacuum bag 22, so that the curing pressure in the rubber core mold inner cavity and the curing pressure outside the outer vacuum bag 22 are the same in the curing process.

8. And demolding after curing.

Comparative example 1

The procedure of example 2 was followed except that the pneumatic outer surface composite material cover plate 17 was not used in step 7, as compared with example 2.

And (3) detection results:

1. appearance of the product

Referring to fig. 9, in comparative example 1, the composite cover plate mentioned in the patent is not used, and it can be seen from the appearance inspection report that the aerodynamic external surface of the part skin has obvious large-area pits along the stringer area and the stringer edge area, and the maximum pit depth exceeds 1mm. The long purlin frock face of wallboard does not have to glue tumour, poor gluey, does not have the fish tail and the fibre splitting of destroying fibre, does not have the visual mix with of seeing, and the fibre does not have the bending fold. Referring to fig. 10, in example 2, the composite cover plate mentioned in the patent is used, and the surface quality of the pneumatic outer surface of the skin is good, no dent is generated, and the appearance inspection is qualified. Visual inspection of the appearance quality of the wallboard shows that the stringer face of the wallboard does not have burrs or poor glue, does not have scratches and fiber splitting which damage fibers, does not have impurities, does not have bent wrinkles on the fibers, and does not have edge layering at the bottom of the stringer cap.

2. Ultrasound report

The wallboard of embodiment 2 of the invention is detected, standard CPS8211H is detected, standard W538RP152 is accepted, specification MIS-Q0001_ A is detected, procedure IR-Q5391W20301S200_ trial version is detected, and ATTU + MPE is detected. The detection result is as shown in fig. 11, and the detection result is qualified and meets the acceptance requirement of the W538RP152 specification.

As can be seen from the ultrasonic testing report of fig. 11, the nondestructive testing was acceptable.

3. Thickness of

The thickness of the panel of example 2 of the invention was measured using a magnetic thickness gauge (one point calibration). The panels were spaced 250mm apart along the course direction, with 13 thickness measurement points arranged as shown in FIG. 12.

1) Skin non-co-cured area

Nominal thickness of the skin non-co-cured area is 2.057mm; tolerance is +/-5%; single value received value: 1.954-2.159 mm. The thickness of the non-co-cured skin region meets the requirement.

TABLE 1 skin non-co-cured area thickness

2) Co-cured areas

Nominal co-cured zone thickness 3.740mm; tolerance is +/-5%; single value received value: 3.553-3.927 mm. The thickness of the co-curing area meets the requirement.

TABLE 2 thickness of co-cured region

The hat-shaped stringer stiffened wall plate is manufactured by the scheme, the thicknesses of the skin area and the co-curing area are detected by a magnetic thickness gauge, and the detection results are qualified.

The foregoing embodiments are merely illustrative of the principles and utilities of the present invention and are not intended to limit the invention. Those skilled in the art can modify or change the above-described embodiments without departing from the spirit and scope of the present invention. Accordingly, it is intended that all equivalent modifications or changes which can be made by those skilled in the art without departing from the spirit and technical spirit of the present invention be covered by the claims of the present invention.

Claims (10)

1. A pneumatic outer-surface composite cover plate is characterized by comprising a first tooling fabric layer, a second tooling fabric layer, a third tooling fabric layer and a fourth tooling fabric layer which are sequentially stacked; the content of resin in the first tooling fabric layer is 45% -50%; the content of resin in the second tooling fabric layer is 35-40%; the content of resin in the third tooling fabric layer is 35-40%; the content of the resin in the fourth tooling fabric layer is 45-50%.

2. The aerodynamic profile composite cover plate of claim 1, wherein the ply angle of the first tooling fabric layer is 0 °, +90 °, or-90 °;

and/or the thickness of the first tooling fabric layer is 0.2 mm-0.3 mm.

3. The aerodynamic profile composite cover of claim 1 wherein the ply angle of the second tooling fabric layer is +45 ° or-45 °;

and/or the thickness of the second tooling fabric layer is 0.6 mm-0.7 mm.

4. The aerodynamic profile composite cover of claim 1, wherein a ply angle of the third tooling fabric layer is +45 ° or-45 °;

and/or the thickness of the third tooling fabric layer is 0.6-0.7 mm.

5. The aerodynamic profile composite cover plate of claim 1, wherein the ply angle of the fourth tooling fabric layer is 0 °, +90 °, or-90 °;

and/or the thickness of the fourth tooling fabric layer is 0.2 mm-0.3 mm.

6. The method for preparing a pneumatic profiled composite cover plate according to any of claims 1 to 5, comprising the steps of:

s1: brushing a release agent on a cover plate forming tool, paving a layer of first tool fabric prepreg on the surface of the cover plate forming tool after the release agent is completely dried, and performing pre-compaction after paving to obtain a first pre-compacted tool fabric;

s2: paving and pasting a second pre-compaction tool fabric prepreg on the first pre-compaction tool fabric provided in the step S1, and pre-compacting after paving and pasting to obtain a second pre-compaction tool fabric;

s3, paving and pasting a third pre-compaction tool fabric prepreg on the second pre-compaction tool fabric provided in the step S2, and pre-compacting after paving and pasting to obtain a third pre-compaction tool fabric;

s4: paving and sticking a fourth tool fabric prepreg on the third pre-compacted tool fabric provided in the step S3, and pre-compacting after paving and sticking are finished to obtain a fourth pre-compacted tool fabric;

s5: putting each layer of pre-compacted tooling fabric into a vacuum bag for sealing;

s6: and (3) performing precuring, removing the bag and demoulding after precuring is finished, and performing postcuring to obtain the pneumatic profile composite cover plate.

7. The method for manufacturing a pneumatic profile composite cover plate according to claim 6, wherein in the pre-compaction process of step S1, the compaction time is not less than 15min, and the compaction vacuum degree is less than-80 KPa;

and/or in the step S1, the content of resin in the prepreg of the first tooling fabric is 45-50%;

and/or in the step S1, the ply angle of the first tooling fabric prepreg is 0 degree, +90 degrees or-90 degrees;

and/or in the step S2, in the pre-compaction process, the compaction time is not less than 15min, and the compaction vacuum degree is less than minus 80KPa;

and/or in the step S2, the content of the resin in the second tooling fabric prepreg is 35-40%;

and/or in the step S2, the ply angle of the second tooling fabric prepreg is +45 degrees or-45 degrees;

and/or in the step S3, in the pre-compaction process, the compaction time is not less than 15min, and the compaction vacuum degree is less than minus 80KPa;

and/or in the step S3, the content of the resin in the third tooling fabric prepreg is 35-40%;

and/or in the step S3, the ply angle of the third tooling fabric prepreg is +45 degrees or-45 degrees;

and/or in the step S4, in the pre-compaction process, the compaction time is not less than 15min, and the compaction vacuum degree is less than minus 80KPa;

and/or in the step S4, the content of the resin in the fourth tooling fabric prepreg is 45-50%;

and/or in step S4, the ply angle of the fourth tooling fabric prepreg is 0 degrees, +90 degrees or-90 degrees.

8. The method for preparing the pneumatic profile composite cover plate according to claim 6, wherein in the step S6, the precuring pressure is 0.4MPa to 0.7MPa, the whole curing process is vacuumized, the temperature is raised to 60 ℃ to 63 ℃ at the temperature raising rate of 0.5 ℃/min to 1.0 ℃/min, and the temperature is maintained for 16 to 17 hours;

and/or, no pressure, no vacuum during post-cure; heating to 60-63 ℃ at a speed of 1-2 ℃/min, heating to 200-203 ℃ at a speed of 0.3-0.5 ℃/min, keeping the temperature for 15-20 min, cooling to 190 ℃ at a speed of 1-2 ℃/min, keeping the temperature for 8 h, cooling to room temperature at a speed of no more than 3.0 ℃/min, and finishing curing.

9. Use of an aerodynamic profile composite decking as claimed in any one of claims 1 to 5 in the manufacture of stringer stiffened co-cured siding.

10. A processing technology of a stringer stiffened co-cured wallboard is characterized by comprising the following steps:

1) Assembling the inner core mold and the flexible rubber core mold to obtain an inner core mold and flexible rubber core mold assembly;

2) Turning the net-size stringer into a female die forming tool; the net-size stringer comprises a stringer crown, two symmetrically distributed stringer waists, and two symmetrically distributed stringer flanges;

3) Placing the inner core mould and the flexible rubber core mould assembly in the step 1) into an inner cavity of the net-size stringer;

4) Filling the twill strips into the residual gaps of the inner cavity of the stringer by utilizing laser projection positioning, sleeving a temporary vacuum bag on the outer surface of the stringer and compacting, wherein the assembled cap bottom of the rubber core die, the twill strips, the stringer flanges and the skin paving area of the female die forming tool are parallel and level;

5) The end part of the net-size stringer is provided with a hard cover plate; a cover plate groove matched with the hard cover plate is formed in the female die forming tool; arranging the hard cover plate in the cover plate groove;

6) Skin spreading and silk spreading are carried out on a skin spreading and pasting area of the female die forming tool, a fringe area of the stringer and a cap bottom area of the flexible rubber core die, skin is formed after silk spreading is finished, and the inner core die is taken out;

7) Fixing the pneumatic profile composite cover plate according to any one of claims 1 to 5 on the outer surface of the skin, wherein an outer vacuum bag is arranged on the pneumatic profile composite cover plate, the outer vacuum bag and the pneumatic profile composite cover plate are sealed by a first sealing rubber strip, and the tubular vacuum bag is communicated with the outer vacuum bag;

8) And demolding after curing.

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