CN117885250A - Die for composite cable cover and preparation method - Google Patents
Die for composite cable cover and preparation method Download PDFInfo
- Publication number
- CN117885250A CN117885250A CN202410217362.XA CN202410217362A CN117885250A CN 117885250 A CN117885250 A CN 117885250A CN 202410217362 A CN202410217362 A CN 202410217362A CN 117885250 A CN117885250 A CN 117885250A
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- cable cover
- composite material
- carbon fiber
- layer
- fiber composite
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- 239000002131 composite material Substances 0.000 title claims abstract description 99
- 238000002360 preparation method Methods 0.000 title claims abstract description 10
- 229920000049 Carbon (fiber) Polymers 0.000 claims abstract description 45
- 239000004917 carbon fiber Substances 0.000 claims abstract description 45
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims abstract description 45
- 239000004744 fabric Substances 0.000 claims abstract description 20
- 238000010438 heat treatment Methods 0.000 claims abstract description 9
- 238000001816 cooling Methods 0.000 claims abstract description 6
- 238000012805 post-processing Methods 0.000 claims abstract description 6
- 238000005498 polishing Methods 0.000 claims abstract description 4
- 238000002955 isolation Methods 0.000 claims description 15
- 238000000605 extraction Methods 0.000 claims description 9
- 238000004519 manufacturing process Methods 0.000 claims description 8
- 238000000034 method Methods 0.000 claims description 8
- 238000009423 ventilation Methods 0.000 claims description 7
- 238000013461 design Methods 0.000 claims description 3
- 239000000463 material Substances 0.000 claims description 3
- -1 polytetrafluoroethylene Polymers 0.000 claims description 3
- 229920001343 polytetrafluoroethylene Polymers 0.000 claims description 3
- 239000004810 polytetrafluoroethylene Substances 0.000 claims description 3
- 238000007789 sealing Methods 0.000 claims description 3
- 238000005086 pumping Methods 0.000 claims 1
- 238000010792 warming Methods 0.000 claims 1
- 239000007787 solid Substances 0.000 abstract description 6
- 238000010112 shell-mould casting Methods 0.000 abstract description 2
- 238000001723 curing Methods 0.000 description 17
- 230000000694 effects Effects 0.000 description 5
- 230000007797 corrosion Effects 0.000 description 2
- 238000005260 corrosion Methods 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 230000008646 thermal stress Effects 0.000 description 2
- 238000012546 transfer Methods 0.000 description 2
- 229910000838 Al alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000005672 electromagnetic field Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000013007 heat curing Methods 0.000 description 1
- 230000002452 interceptive effect Effects 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000000246 remedial effect Effects 0.000 description 1
- 238000007493 shaping process Methods 0.000 description 1
- 238000007711 solidification Methods 0.000 description 1
- 230000008023 solidification Effects 0.000 description 1
- 238000001029 thermal curing Methods 0.000 description 1
Landscapes
- Casting Or Compression Moulding Of Plastics Or The Like (AREA)
Abstract
The invention discloses a die and a preparation method of a composite material cable cover, and relates to the technical field of solid rocket engine shell molding. The preparation method comprises the following steps: s1: preparing a mold; s2: sticking demolding cloth on the molded surface; s3: laying a plurality of layers of carbon fiber composite material prepregs on release cloth to obtain a preformed cable cover; s4, paving a layer of isolating film and airfelt on the preformed cable cover, preparing a layer of vacuum bag film, and vacuumizing a cavity between the vacuum bag film and the top plate through a vacuum pump; s5: heating and solidifying; s6: taking out and cooling, and then removing the airfelt, the isolating film and the vacuum bag film; s7: surface polishing treatment and post-processing treatment. The negative quality of the whole engine shell is reduced, and the efficiency and performance of the engine shell are improved.
Description
Technical Field
The invention relates to the technical field of solid rocket engine shell molding, in particular to a die of a composite material cable cover and a preparation method thereof.
Background
Cable covers are an important component on solid rocket engines and are used to protect the cables and connectors on the solid rocket engine housing from environmental conditions, vibrations, heat and other factors that may cause damage to the solid rocket engine during its ignition and flight. In addition, the cable cover may also be used to secure and organize the cables to ensure that they do not loosen or become entangled with other components during rocket launch.
The cable covers in existing engine housings are typically made of aluminum alloy materials, which can reduce the life of the metal cable covers and cause maintenance problems due to the high negative mass and susceptibility to corrosion, especially in the harsh environment of a solid rocket engine during ignition and flight. Furthermore, metallic cable covers may cause electromagnetic interference, particularly for sensitive cables and equipment, which may become conductors of electromagnetic fields, thereby interfering with the proper functioning of the signals and electronics inside the cable.
Disclosure of Invention
The invention aims to provide a die and a preparation method of a composite material cable cover, which are used for solving the problems of the prior art, reducing the negative quality of the cable cover in an engine shell and improving the production efficiency and performance of the cable cover.
In order to achieve the above object, the present invention provides the following solutions:
the invention provides a die of a composite material cable cover, which comprises a support frame and a top plate fixedly arranged at the top end of the support frame, wherein the top surface of the top plate is provided with a molded surface, and the shape and the size of the molded surface are the same as those of the inner surface of the composite material cable cover to be molded; each side wall of the support frame is provided with a plurality of ventilation openings, and at least three movable wheels are arranged at the bottom end of the support frame.
Preferably, the profile is provided with bumps corresponding to the electronic component grooves in the inner surface of the composite cable cover, and the shape and the size of the bumps are the same as those of the electronic component grooves.
The invention also provides a preparation method of the composite cable cover, which comprises the following steps:
s1: preparing a mould of the composite material cable cover;
s2: preparing release cloth, and adhering the release cloth on the molded surface of the mold;
s3: preparing a plurality of layers of carbon fiber composite material prepregs, and sequentially paving all the carbon fiber composite material prepregs on the release cloth from bottom to top to obtain a preformed cable cover;
s4, paving a layer of isolation film on the preformed cable cover, paving a layer of airfelt on the surface of the isolation film, preparing a layer of vacuum bag film, sealing and connecting the edge of the vacuum bag film with the top plate, reserving an extraction opening, enabling the airfelt, the isolation film and the preformed cable cover to be positioned below the vacuum bag film, and communicating a cavity between the vacuum bag film and the top plate with the extraction opening; then compacting all of the carbon fiber composite prepreg across the vacuum bagging film; then the air extraction opening is communicated with a vacuum pump, the cavity is vacuumized through the vacuum pump, and the pressure is maintained for a set time;
s5: feeding the mold together with the preformed cable cover, the airfelt, the isolating film and the vacuum bag film into a furnace for heating and curing, so that the preformed cable cover is cured into a composite cable cover, and maintaining the cavity in a vacuum state during heating and curing;
s6: taking the die together with the composite material cable cover, the airfelt, the isolation film and the vacuum bag film out of the furnace, removing the airfelt, the isolation film and the vacuum bag film when the die is cooled to a temperature lower than 20 ℃ higher than the ambient temperature, and taking down the composite material cable cover;
s7: and carrying out surface polishing treatment and post-processing treatment on the composite material cable cover until the composite material cable cover meets the design requirement.
Preferably, the release cloth is made of polytetrafluoroethylene.
Preferably, the carbon fiber composite prepreg has five layers, and the process of sequentially laying all the carbon fiber composite prepreg on the release cloth from bottom to top comprises the following steps:
(1) Paving a first layer of carbon fiber composite material prepreg on the release cloth by adopting 90 degrees;
(2) Paving a second layer of carbon fiber composite material prepreg on the first layer of carbon fiber composite material by adopting 0 DEG;
(3) Paving a third layer of carbon fiber composite material prepreg on the second layer of carbon fiber composite material by adopting 45 degrees;
(4) Paving a fourth layer of carbon fiber composite material prepreg on the third layer of carbon fiber composite material by adopting-45 degrees;
(5) And paving the carbon fiber composite material prepreg of the fifth layer on the carbon fiber composite material of the fourth layer by adopting 90 degrees.
Preferably, in step S4, the set time for maintaining the pressure after the evacuation is 15 minutes.
Preferably, the thermal curing in step S5 includes the following four stages:
the first stage: the curing temperature is 50 ℃ and the curing time is 1 hour;
and a second stage: the curing temperature is 130 ℃ and the curing time is 1 hour;
and a third stage: the curing temperature is 160 ℃ and the curing time is 1 hour;
fourth stage: cooling to below 60 ℃ along with the furnace.
Preferably, step S5 needs to be performed within 48 hours after step S3 is completed.
Compared with the prior art, the invention has the following technical effects:
the composite material cable cover prepared by the die and the preparation method of the composite material cable cover has very high specific modulus and specific strength, can reduce the negative quality of the whole engine shell, and improves the efficiency and performance of the engine shell.
Further, the composite material cable cover contains the carbon fiber composite material, and the carbon fiber composite material has good high-temperature stability, corrosion resistance and impact resistance, so that the composite material cable cover can work in a severe environment without failure.
Further, the furnace temperature is monitored in real time in the heating and solidifying process, the solidifying temperature curve is controlled, and the temperature is reduced along with the furnace in cooling, so that the thermal stress can be effectively reduced, and the deformation degree of the formed part is reduced.
Further, the mold of the composite cable cover has good ventilation effect and heat transfer effect, can effectively improve the uniformity of temperature distribution of the inner mold surface, reduce the curing gradient and improve the molding precision of the cable cover.
Further, the post-processing treatment of the cable cover prefabricated member is finally carried out, and as the processing allowance is reserved in the process of designing the die, the forming precision of the cable cover can be effectively ensured in the post-processing treatment.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions of the prior art, the drawings that are needed in the embodiments will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic structural view of a first embodiment of a mold for a composite cable cover of the present invention;
FIG. 2 is a schematic structural view of a first embodiment of a composite cable cover of the present invention;
FIG. 3 is a schematic diagram of a second embodiment of a mold for a composite cable cover of the present invention;
FIG. 4 is a flow chart of a method of making a composite cable cover in accordance with a third embodiment of the present invention;
wherein, 1, the profile; 2. a support frame; 3. a top plate; 4. a moving wheel; 5. an air ventilation port; 6. and a bump.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
The invention aims to provide a die and a preparation method of a composite material cable cover, which are used for solving the problems of the prior art, reducing the negative quality of the cable cover in an engine shell and improving the production efficiency and performance of the cable cover.
In order that the above-recited objects, features and advantages of the present invention will become more readily apparent, a more particular description of the invention will be rendered by reference to the appended drawings and appended detailed description.
Example 1
As shown in fig. 1 and 2, the embodiment provides a mold for a composite cable cover, which comprises a support frame 2 and a top plate 3 fixedly arranged at the top end of the support frame 2, wherein a molded surface 1 is arranged on the top surface of the top plate 3, and the shape and the size of the molded surface 1 are the same as those of the inner surface of the composite cable cover to be molded.
Each lateral wall of support frame 2 all is provided with a plurality of ventilation openings 5, and ventilation effect of the mould of combined material cable cover has been strengthened in the setting of ventilation opening 5, and the material of support frame 2 is the metal, has better heat transfer effect, can improve mould inner profile 1 temperature distribution homogeneity, reduces the solidification gradient, improves the shaping precision of cable cover.
Six movable wheels 4 are installed at the bottom end of the support frame 2, and manpower can be effectively saved when the mould of the composite material cable cover is carried and moved through the arrangement of the movable wheels 4.
Example two
As shown in fig. 3, this embodiment provides a mold for a composite cable cover, and the mold for a composite cable cover provided in this embodiment has substantially the same structure as the mold for a composite cable cover of the first embodiment, except that: the profile 1 of the top plate 3 is provided with bumps 6 corresponding to the electronic component grooves in the inner surface of the composite cable cover, the shape and size of the bumps 6 being the same as the shape and size of the electronic component grooves.
Example III
As shown in fig. 4, this embodiment provides a method for preparing a composite cable cover, which includes the following steps:
s1: preparing a mold of the composite cable cover of the first embodiment or the second embodiment;
s2: preparing release cloth, and adhering the release cloth on the molded surface 1 of the mold;
s3: preparing a plurality of layers of carbon fiber composite material prepregs, and sequentially paving all the carbon fiber composite material prepregs on release cloth from bottom to top to obtain a preformed cable cover;
s4, paving a layer of isolation film on the preformed cable cover, paving a layer of airfelt on the surface of the isolation film, preparing a layer of vacuum bag film, sealing and connecting the edge of the vacuum bag film with the top plate 3, reserving an extraction opening, enabling the airfelt, the isolation film and the preformed cable cover to be positioned below the vacuum bag film, and communicating a cavity between the vacuum bag film and the top plate 3 with the extraction opening; then compacting all the carbon fiber composite prepreg through a vacuum bag film; then the air extraction opening is communicated with a vacuum pump, the cavity is vacuumized through the vacuum pump, and the pressure is maintained for a set time;
s5: feeding the mould together with the preformed cable cover, the airfelt, the isolating film and the vacuum bag film into a furnace for heating and curing, so that the preformed cable cover is cured into a composite cable cover, and maintaining the cavity in a vacuum state during heating and curing;
s6: taking the mould together with the composite material cable cover, the airfelt, the isolation film and the vacuum bag film out of the furnace, removing the airfelt, the isolation film and the vacuum bag film when the temperature is cooled to be lower than 20 ℃ higher than the ambient temperature, and taking down the composite material cable cover;
s7: and (3) carrying out surface polishing treatment and post-processing treatment on the composite material cable cover until the composite material cable cover meets the design requirements.
In an alternative to this embodiment, the release cloth is preferably polytetrafluoroethylene.
In an alternative of this embodiment, preferably, the carbon fiber composite prepreg has five layers, and the process of sequentially laying all the carbon fiber composite prepregs on the release cloth from bottom to top includes the following steps:
(1) Paving a first layer of carbon fiber composite material prepreg on release cloth by adopting 90 degrees;
(2) Paving a second layer of carbon fiber composite material prepreg on the first layer of carbon fiber composite material by adopting 0 DEG;
(3) Paving the prepreg of the third layer of carbon fiber composite material on the second layer of carbon fiber composite material by adopting 45 degrees;
(4) Paving a fourth layer of carbon fiber composite material prepreg on the third layer of carbon fiber composite material by adopting-45 degrees;
(5) The fifth layer carbon fiber composite material prepreg was laid on the fourth layer carbon fiber composite material using 90 °.
In the alternative of this embodiment, preferably, in step S4, the set time of maintaining the pressure after vacuumizing is 15 minutes, then the air pressure in the cavity is checked, the pressure loss is less than 0.002MPa, otherwise, the air leakage position is searched and remedial measures are taken in time.
In an alternative of the present embodiment, it is preferable that the heat curing in step S5 includes the following four stages:
the first stage: the curing temperature is 50 ℃ and the curing time is 1 hour;
and a second stage: the curing temperature is 130 ℃ and the curing time is 1 hour;
and a third stage: the curing temperature is 160 ℃ and the curing time is 1 hour;
fourth stage: cooling to below 60 ℃ along with the furnace.
The furnace temperature is monitored in real time in the heating and solidifying process, the solidifying temperature curve is controlled, and the temperature is reduced along with the furnace during cooling, so that the thermal stress can be effectively reduced, and the deformation degree of the formed part is reduced.
In the alternative of this embodiment, it is preferable that step S5 is performed within 48 hours after step S3 is completed.
In the description of the present invention, it should be noted that the positional or positional relationship indicated by the terms such as "top", "upper", "lower", etc. are based on the positional or positional relationship shown in the drawings, are merely for convenience of describing the present invention and simplifying the description, and are not indicative or implying that the apparatus or element in question must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
The principles and embodiments of the present invention have been described in detail with reference to specific examples, which are provided to facilitate understanding of the method and core ideas of the present invention; also, it is within the scope of the present invention to be modified by those of ordinary skill in the art in light of the present teachings. In view of the foregoing, this description should not be construed as limiting the invention.
Claims (8)
1. The utility model provides a mould of combined material cable cover which characterized in that: the cable cover comprises a support frame and a top plate fixedly arranged at the top end of the support frame, wherein the top surface of the top plate is provided with a molded surface, and the shape and the size of the molded surface are the same as those of the inner surface of a composite cable cover to be molded; each side wall of the support frame is provided with a plurality of ventilation openings, and at least three movable wheels are arranged at the bottom end of the support frame.
2. The mold of a composite cable jacket of claim 1, wherein: and the profile is provided with a lug corresponding to the electronic element groove in the inner surface of the composite cable cover, and the shape and the size of the lug are the same as those of the electronic element groove.
3. The preparation method of the composite cable cover is characterized by comprising the following steps of:
s1: preparing a mould for a composite cable cover as claimed in claim 1 or 2;
s2: preparing release cloth, and adhering the release cloth on the molded surface of the mold;
s3: preparing a plurality of layers of carbon fiber composite material prepregs, and sequentially paving all the carbon fiber composite material prepregs on the release cloth from bottom to top to obtain a preformed cable cover;
s4, paving a layer of isolation film on the preformed cable cover, paving a layer of airfelt on the surface of the isolation film, preparing a layer of vacuum bag film, sealing and connecting the edge of the vacuum bag film with the top plate, reserving an extraction opening, enabling the airfelt, the isolation film and the preformed cable cover to be positioned below the vacuum bag film, and communicating a cavity between the vacuum bag film and the top plate with the extraction opening; then compacting all of the carbon fiber composite prepreg across the vacuum bagging film; then the air extraction opening is communicated with a vacuum pump, the cavity is vacuumized through the vacuum pump, and the pressure is maintained for a set time;
s5: feeding the mold together with the preformed cable cover, the airfelt, the isolating film and the vacuum bag film into a furnace for heating and curing, so that the preformed cable cover is cured into a composite cable cover, and maintaining the cavity in a vacuum state during heating and curing;
s6: taking the die together with the composite material cable cover, the airfelt, the isolation film and the vacuum bag film out of the furnace, removing the airfelt, the isolation film and the vacuum bag film when the die is cooled to a temperature lower than 20 ℃ higher than the ambient temperature, and taking down the composite material cable cover;
s7: and carrying out surface polishing treatment and post-processing treatment on the composite material cable cover until the composite material cable cover meets the design requirement.
4. A method of making a composite cable jacket according to claim 3, wherein: the demolding cloth is made of polytetrafluoroethylene.
5. A method of making a composite cable jacket according to claim 3, wherein: the carbon fiber composite prepreg has five layers, and the process of sequentially paving all the carbon fiber composite prepreg on the release cloth from bottom to top comprises the following steps:
(1) Paving a first layer of carbon fiber composite material prepreg on the release cloth by adopting 90 degrees;
(2) Paving a second layer of carbon fiber composite material prepreg on the first layer of carbon fiber composite material by adopting 0 DEG;
(3) Paving a third layer of carbon fiber composite material prepreg on the second layer of carbon fiber composite material by adopting 45 degrees;
(4) Paving a fourth layer of carbon fiber composite material prepreg on the third layer of carbon fiber composite material by adopting-45 degrees;
(5) And paving the carbon fiber composite material prepreg of the fifth layer on the carbon fiber composite material of the fourth layer by adopting 90 degrees.
6. A method of making a composite cable jacket according to claim 3, wherein: in step S4, the set time for maintaining the pressure after the vacuum pumping is 15 minutes.
7. A method of making a composite cable jacket according to claim 3, wherein: the warming curing described in step S5 includes the following four stages:
the first stage: the curing temperature is 50 ℃ and the curing time is 1 hour;
and a second stage: the curing temperature is 130 ℃ and the curing time is 1 hour;
and a third stage: the curing temperature is 160 ℃ and the curing time is 1 hour;
fourth stage: cooling to below 60 ℃ along with the furnace.
8. A method of making a composite cable jacket according to claim 3, wherein: step S5 needs to be performed within 48 hours after step S3 is completed.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410217362.XA CN117885250A (en) | 2024-02-27 | 2024-02-27 | Die for composite cable cover and preparation method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410217362.XA CN117885250A (en) | 2024-02-27 | 2024-02-27 | Die for composite cable cover and preparation method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117885250A true CN117885250A (en) | 2024-04-16 |
Family
ID=90651990
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202410217362.XA Pending CN117885250A (en) | 2024-02-27 | 2024-02-27 | Die for composite cable cover and preparation method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117885250A (en) |
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2024
- 2024-02-27 CN CN202410217362.XA patent/CN117885250A/en active Pending
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