A kind of aramid honeycomb core material is used in rocket propeller cylinder light weight edge 10 slotting

Abstract

This invention relates to the field of rocket propulsion auxiliary materials technology, and discloses a slotted aramid honeycomb core material for lightweight rocket propulsion cylinders, comprising a large-side-length slotted overstretched aramid honeycomb material. The large-side-length slotted overstretched aramid honeycomb material is characterized by being composed of YT822A aramid paper, core strip adhesive, phenolic resin, and alcohol. The YT822A aramid paper is coated with core strip adhesive and dried. It is then cut to a fixed length using a paper cutter and stacked into aramid paper honeycomb blocks. The stacked aramid paper honeycomb blocks are then hot-pressed using a hot press to bond and solidify the core strip adhesive inside the aramid paper honeycomb blocks. After hot pressing for a certain period, the aramid paper honeycomb blocks are air-cooled, and the excess edges of the aramid paper honeycomb blocks are trimmed again using a paper cutter. This preparation method has advantages such as improving the production quality of the large-side-length slotted overstretched aramid honeycomb material.

Description

Technical Field

[0001] This invention relates to the field of rocket propulsion auxiliary materials technology, specifically to a grooved aramid honeycomb core material for lightweight rocket propulsion cylinders. Background Technology

[0002] Large-side-length slotted overstretched aramid honeycomb material, used in rocket booster cylinders, is a low-density, overstretched honeycomb material. It is used as the core material for sandwich structures and can be manufactured from over 500 different materials. The main honeycomb core materials include aramid paper, pulp, aramid 1313 fiber paper, kraft paper, plant fibers, and aramid 1414 (Kevlar) fiber, with resin content varying around 50%. Overstretched honeycomb cores come in various sizes, such as 3.67mm, 4.0mm, 5.5mm, 8mm, 10mm, and 12mm. Its performance depends on the material and the size of the cell sides, exhibiting anisotropy. The shear strength of the slotted overstretched honeycomb core material along the L direction is not significantly different from that along the W direction. After molding, the planar compression requirement for large-side-length slotted overstretched aramid honeycomb material is ≥0.75MPa. It is mainly used as the sandwich core material for aerospace rocket booster cylinders. The use of large-side-length slotted overstretched aramid honeycomb in lightweight rocket booster cylinders represents a technological advancement.

[0003] Existing large-side-length slotted overstretched aramid honeycomb materials are typically produced through steps such as coating, lamination, pressing, stretching, shaping, impregnation, curing, sheet cutting, and slotting. However, slotting the honeycomb sidewalls reduces the bonding area between the honeycomb and the skin, inevitably lowering the shear strength and planar tensile strength of the structure. Furthermore, slotting, being the final step, generates a large amount of fly lint, severely contaminating the finished product and resulting in low actual processing quality. Existing equipment has room for further improvement in the production quality of large-side-length slotted overstretched aramid honeycomb materials. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a lightweight aramid honeycomb core material with 10-slotted edges for use in rocket propulsion cylinders, which has advantages such as improving the production quality of large-side-length slotted and overstretched aramid honeycomb materials.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a lightweight aramid honeycomb core material with 10 grooved edges for use in rocket propulsion cylinders, comprising a large-side-length grooved overstretched aramid honeycomb material, wherein the large-side-length grooved overstretched aramid honeycomb material is composed of YT822A aramid paper, core strip adhesive, phenolic resin, and alcohol.

[0006] A method for preparing a lightweight 10-groove aramid honeycomb core material for rocket booster cylinders includes: S1. Coat YT822A aramid paper with core strip adhesive, dry it, and then cut it to a fixed length using a paper cutter to stack it into aramid paper honeycomb blocks. S2. Use a hot press to hot press the stacked aramid paper honeycomb blocks to allow the core strip adhesive inside the aramid paper honeycomb blocks to bond and solidify. S3. After hot pressing in the hot press for a certain period of time, the aramid paper honeycomb stack is cooled by air cooling, and the excess edges of the aramid paper honeycomb stack are trimmed again by the paper cutter. S4. Place the trimmed aramid paper honeycomb stack on a paper cutter and cut multiple honeycomb strips according to a certain thickness. S5. Then place multiple cut honeycomb strips in a fixed fixture and use an automated honeycomb grooving machine to groove the cut honeycomb strips in the fixed fixture. S6. Stretch the slotted honeycomb strips to the required length and width to form a slotted overstretched aramid honeycomb, and fix the slotted overstretched aramid honeycomb on the bracket. S7. Dilute the prepared phenolic resin with alcohol in advance, mix it in a certain proportion, measure the viscosity of the mixed phenolic resin and record it. S8. Weigh and record the weight of the slotted overstretched aramid honeycomb fixed by the bracket. Impregnate the slotted overstretched aramid honeycomb inside the bracket multiple times in a phenolic resin chamber and dry it in time after impregnation. S9. After drying and forming, the slotted and stretched aramid honeycomb is removed from the fixed support and unloaded. A paper cutter is used to trim the edges again. The data of the slotted and stretched aramid honeycomb after drying and forming is weighed and recorded. S10. Inspect the overall quality of the grooved and stretched aramid honeycomb. Once all the quality is qualified, package and ship it in a timely manner.

[0007] Preferably, in step S1, the drying step is carried out in an oven, and the drying temperature is 60~180℃.

[0008] Preferably, in step S5, the cut honeycomb is placed in a fixed fixture, and an automated honeycomb grooving machine is used to perform single-wall grooving, thereby forming multiple honeycomb holes at the cut honeycomb. After single-wall grooving, each honeycomb hole can allow air convection.

[0009] Preferably, in step S5, the large side length of each cell in the cut honeycomb is set to 10±0.5mm.

[0010] Preferably, in step S8, the grooved and stretched aramid honeycomb fixed on the bracket is immersed in phenolic resin, and after immersion, it is placed in a curing oven for drying. The immersion process is repeated multiple times to achieve the specified density for the pre-impregnated honeycomb product application. The drying temperature is set at 60±5℃ and the curing temperature is set at 180±5℃, thereby completing multiple immersion and drying steps.

[0011] Preferably, in step S8, the thickness range of the grooved and stretched aramid honeycomb is 8~23mm, and the final set density of the grooved and stretched aramid honeycomb after multiple impregnations and drying is 32~48Kg / m³. 3 .

[0012] Preferably, in step S9, the slotted and stretched aramid honeycomb is disassembled from the support and trimmed a second time using a paper cutter. The width of the trimmed slotted and stretched aramid honeycomb should meet 1220*2440mm. The actual density of each trimmed slotted and stretched aramid honeycomb is weighed and verified, the actual thickness is measured, and the regularity of the prepreg honeycomb cells is visually inspected. After confirming that the design technical requirements are met, step S10 is carried out to package and ship the product in a timely manner.

[0013] Beneficial effects 1. This material is used in the lightweight edge-grooved aramid honeycomb core of rocket booster cylinders. Through the production steps of first grooving the cut honeycomb strips and then impregnating them with resin, the phenolic resin will, like a "glaze", perfectly wrap all the burrs and debris generated by grooving in the stretched aramid honeycomb, completely eliminating the risk of foreign matter residue.

[0014] 2. This lightweight 10-grooved aramid honeycomb core material used in rocket booster cylinders avoids quality problems such as product warping and deformation caused by grooving only on one side after impregnation by pre-grooving the cut honeycomb strips and then impregnating them with glue, thus ensuring that the future covering effect perfectly fits the mold.

[0015] 3. This 10-grooved aramid honeycomb core material used in the lightweight edge of rocket booster cylinders is produced by first grooving the cut honeycomb strips and then impregnating them with resin. In the subsequent steps, phenolic resin penetrates into the honeycomb cells, so that the grooved surface itself can form a naturally reinforced edge, thereby making the structure denser and stronger. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the production steps of a lightweight aramid honeycomb core material with 10 grooves on the side of a rocket propulsion cylinder according to the present invention. Figure 2 This is a schematic diagram of a slotted honeycomb structure for a lightweight aramid honeycomb core material used in rocket propulsion cylinders according to the present invention. Figure 3 This is a schematic diagram of a honeycomb lattice structure with large side length of the slotted aramid honeycomb core material used in the lightweight rocket propulsion cylinder of the present invention. Figure 4 This is a schematic diagram of the appearance structure of a slotted aramid honeycomb core material used in the lightweight side of a rocket propulsion cylinder according to the present invention. Figure 5This is a schematic diagram of an installation structure for a slotted aramid honeycomb core material used in the lightweight side of a rocket propulsion cylinder according to the present invention. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] Example Please see Figures 1 to 4 A lightweight aramid honeycomb core material with 10 grooves on the side of a rocket booster cylinder, comprising a large-side-length grooved and overstretched aramid honeycomb material, which is composed of YT822A aramid paper, core strip adhesive, phenolic resin, and alcohol. In actual production, existing large-side-length slotted overstretched aramid honeycomb materials are usually produced through steps such as coating, stacking, pressing, stretching, shaping, impregnation, curing, sheet cutting, and slotting. However, slotting the honeycomb sidewalls reduces the bonding area between the honeycomb and the skin, which inevitably reduces the shear strength and planar tensile strength of the structure. Moreover, slotting is the final step, which generates a large amount of flying lint, seriously contaminating the finished product and resulting in low actual processing quality of the material. Existing equipment has room for further improvement in the production quality of large-side-length slotted overstretched aramid honeycomb materials. This invention discloses a lightweight aramid honeycomb core material with 10 slotted edges for use in rocket booster cylinders. S1, YT822A aramid paper is coated with core strip adhesive and dried. It is then cut to a fixed length and stacked into aramid paper honeycomb blocks using a paper cutter. The drying process is carried out in an oven at a temperature of 60~180℃. S2. Use a hot press to hot press the stacked aramid paper honeycomb blocks to allow the core strip adhesive inside the aramid paper honeycomb blocks to bond and solidify. S3. After hot pressing in the hot press for a certain period of time, the aramid paper honeycomb stack is cooled by air cooling, and the excess edges of the aramid paper honeycomb stack are trimmed again by the paper cutter. S4. Place the trimmed aramid paper honeycomb stack on a paper cutter and cut multiple honeycomb strips according to a certain thickness. S5. Then place multiple cut honeycomb cells in a fixed fixture and use an automated honeycomb grooving machine to groove the cut honeycomb cells in the fixed fixture, thereby forming multiple honeycomb holes at the cut honeycomb cells. After single-wall grooving, each honeycomb hole can allow air convection. The large side length of each honeycomb hole at the cut honeycomb cells is set to 10±0.65mm. S6. Stretch the slotted honeycomb strips to the required length and width to form a slotted overstretched aramid honeycomb, and fix the slotted overstretched aramid honeycomb on the bracket. S7. Dilute the prepared phenolic resin with alcohol in advance, mix it in a certain proportion, measure the viscosity of the mixed phenolic resin and record it. S8. Weigh and record the weight of the slotted overstretched aramid honeycomb fixed to the bracket. Impregnate the slotted overstretched aramid honeycomb inside the bracket multiple times in a phenolic resin chamber. Immerse the slotted overstretched aramid honeycomb fixed to the bracket into the phenolic resin, and then place it in a curing oven for drying. Repeat the impregnation process multiple times to achieve the specified density for the pre-impregnated honeycomb product application. The drying temperature should be set at 60±5℃, and the curing temperature at 180±5℃. This completes the multiple impregnation and drying steps. The thickness range of the slotted overstretched aramid honeycomb is 8~23mm. After multiple impregnations and drying, the final shaped density of the slotted overstretched aramid honeycomb is 32~48Kg / m³. 3 ; S9. After drying and forming, the slotted and stretched aramid honeycomb is removed from the fixed support and unloaded. It is then trimmed a second time using a paper cutter. The width of the trimmed slotted and stretched aramid honeycomb should meet 1220*2440mm. Each piece of the trimmed slotted and stretched aramid honeycomb is weighed to check and calculate the actual density and measure the actual thickness. The regularity of the prepreg honeycomb cells is visually checked. After confirming that it meets the design technical requirements, step S10 is carried out and the honeycomb is packaged and shipped in a timely manner. S10. Inspect the overall quality of the grooved and stretched aramid honeycomb. Once all the quality is qualified, package and ship it in a timely manner. This application employs a production process of first grooving the cut honeycomb strips and then impregnating them with resin. On the one hand, grooving first and then impregnating avoids quality problems such as product warping and deformation caused by grooving only on one side after impregnation, ensuring that the future covering effect perfectly fits the mold. On the other hand, in the subsequent impregnation step, the phenolic resin will act like a "glaze," perfectly wrapping all the burrs and debris generated by grooving in the grooved and stretched aramid honeycomb, completely eliminating the risk of foreign matter residue. Furthermore, the phenolic resin penetrates into the honeycomb pores, so that the grooved surface itself can form a naturally reinforced edge, thereby making the structure denser and stronger.

[0019] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A lightweight aramid honeycomb core material with 10-slotted edges for use in rocket booster cylinders, comprising a long-side-length slotted overstretched aramid honeycomb material, characterized in that: The large-side-length slotted overstretched aramid honeycomb material is composed of YT822A aramid paper, core strip adhesive, phenolic resin, and alcohol.

2. A method for preparing a lightweight aramid honeycomb core material with 10 grooves on the edge of a rocket booster cylinder, comprising: S1. Coat YT822A aramid paper with core strip adhesive, dry it, and then cut it to a fixed length using a paper cutter to stack it into aramid paper honeycomb blocks. S2. Use a hot press to hot press the stacked aramid paper honeycomb blocks to allow the core strip adhesive inside the aramid paper honeycomb blocks to bond and solidify. S3. After hot pressing in the hot press for a certain period of time, the aramid paper honeycomb stack is cooled by air cooling, and the excess edges of the aramid paper honeycomb stack are trimmed again by the paper cutter. S4. Place the trimmed aramid paper honeycomb stack on a paper cutter and cut multiple honeycomb strips according to a certain thickness. S5. Then place multiple cut honeycomb strips in a fixed fixture and use an automated honeycomb grooving machine to groove the cut honeycomb strips in the fixed fixture. S6. Stretch the slotted honeycomb strips to the required length and width to form a slotted overstretched aramid honeycomb, and fix the slotted overstretched aramid honeycomb on the bracket. S7. Dilute the prepared phenolic resin with alcohol in advance, mix it in a certain proportion, measure the viscosity of the mixed phenolic resin and record it. S8. Weigh and record the weight of the slotted overstretched aramid honeycomb fixed by the bracket. Impregnate the slotted overstretched aramid honeycomb inside the bracket multiple times in a phenolic resin chamber and dry it in time after impregnation. S9. After drying and forming, the slotted and stretched aramid honeycomb is removed from the fixed support and unloaded. A paper cutter is used to trim the edges again. The data of the slotted and stretched aramid honeycomb after drying and forming is weighed and recorded. S10. Inspect the overall quality of the grooved and stretched aramid honeycomb. Once all the quality is qualified, package and ship it in a timely manner.

3. The method for preparing a lightweight aramid honeycomb core material with grooved edges 10 for use in rocket propulsion cylinders according to claim 2, characterized in that: In step S1, the drying process is carried out in an oven at a temperature of 60~180℃.

4. The method for preparing a lightweight aramid honeycomb core material with grooved edges 10 for use in rocket propulsion cylinders according to claim 2, characterized in that: In step S5, the cut honeycomb is placed in a fixed fixture, and an automated honeycomb grooving machine is used to groove it on one wall, thereby forming multiple honeycomb holes at the cut honeycomb. After the single-wall grooving, each honeycomb hole can allow air convection.

5. A method for preparing a lightweight aramid honeycomb core material with grooved edges 10 for use in rocket propulsion cylinders according to claim 2, characterized in that: In step S5, the large side length of each cell in the cut honeycomb is set to 10 ± 0.5 mm.

6. The method for preparing a lightweight aramid honeycomb core material with grooved edges 10 for use in rocket propulsion cylinders according to claim 2, characterized in that: In step S8, the grooved and stretched aramid honeycomb fixed on the bracket is immersed in phenolic resin and then placed in a curing oven for drying. The immersion process is repeated multiple times to achieve the specified density for the pre-impregnated honeycomb product application. The drying temperature is set at 60±5℃ and the curing temperature at 180±5℃, thus completing multiple immersion and drying steps.

7. A method for preparing a lightweight aramid honeycomb core material with grooved edges 10 for use in rocket propulsion cylinders according to claim 2, characterized in that: In step S8, the thickness range of the grooved and stretched aramid honeycomb is 8~23mm. After multiple impregnations and drying, the final set density of the grooved and stretched aramid honeycomb is 32~48Kg / m³. 3 .

8. A method for preparing a lightweight aramid honeycomb core material with grooved edges 10 for use in rocket propulsion cylinders according to claim 2, characterized in that: In step S9, the slotted and stretched aramid honeycomb is disassembled from the support and trimmed a second time using a paper cutter. The width of the trimmed slotted and stretched aramid honeycomb should meet 1220*2440mm. Each piece of the trimmed slotted and stretched aramid honeycomb is weighed to check and calculate the actual density, and the actual thickness is measured. The regularity of the prepreg honeycomb cells is visually checked. After confirming that it meets the design technical requirements, step S10 is carried out to package and ship the product in a timely manner.

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