Technological method for directionally and controllably splicing large-size curved surface honeycombs

Abstract

The invention discloses a process method for directionally and controllably splicing large-size curved surface honeycombs. The process method comprises the steps of positioning and paving honeycombs, filling powdery polystyrene foam, placing pressurizing blocks, packaging and curing and the like. The curved surface honeycomb is positioned and laid on the inner concave forming face of the curved surface honeycomb forming tool; the filling amount of powdery polystyrene foam is calculated according to the foaming coefficient of 0.5-3, and the powdery polystyrene foam is filled to the splicing position of the two curved surface honeycombs; strippable cloth is integrally laid on the surface of the curved honeycomb, and then pressurizing blocks are placed close to the two sides of the splicing position; and finally packaging and feeding into an autoclave for heating and curing. The curved surface honeycombs filled with the powdery polystyrene foam are evenly spliced, the complete foaming degree is high, meanwhile, the determination of the foaming coefficient means that the polystyrene foam filling amount is quantified, and directional control over the splicing height and the splicing area of the curved surface honeycombs can be achieved. And the operation process is simple, the surface of the abutted seam after curing is smooth, and the forming quality is good. And the quantized filled polystyrene foam can avoid material waste, the part manufacturing cost is reduced, and important engineering application significance is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of large-size curved honeycomb splicing technology, and in particular to a process method for directional and controllable splicing of large-size curved honeycombs. Background Art

[0002] Honeycomb sandwich structures have the advantages of light weight, high strength, resistance to instability, fatigue resistance, sound absorption, and heat insulation, and are widely used in aerospace vehicle structures.

[0003] The honeycomb sandwich structure consists of an upper skin, a honeycomb core material and a lower skin. The core material is usually made of Nomex, aluminum alloy, glass cloth, etc. Affected by the size of the honeycomb raw materials, large-sized curved honeycombs are often made by splicing honeycombs in blocks.

[0004] Foam glue has less volatiles, good mechanical properties, and stable resistance to moisture and heat aging, so it is often used as the preferred material for bonding honeycombs. At present, when using foam glue to splice honeycombs, the quality of the joints is difficult to control, and the skin in this area is prone to dents or wrinkles during subsequent co-gluing.

[0005] Therefore, it is necessary to explore a process method for directional and controllable splicing of large-size curved honeycombs. Summary of the invention

[0006] The purpose of the present invention is to provide a process method for directional and controllable splicing of large-size curved honeycombs, improve the quality of honeycomb splicing seams, avoid depressions or wrinkles in the area when the skin is subsequently laid, and thus manufacture qualified high-thickness and large-curvature honeycomb parts.

[0007] In order to solve the above technical problems, the present invention provides a process method for directional and controllable splicing of large-size curved honeycombs, comprising the following steps: Step A: Positioning and paving the honeycomb: pre-cleaning the curved honeycomb forming tool (1) with a mold release agent, and then positioning and paving a plurality of curved honeycombs (2) on the concave forming surface of the curved honeycomb forming tool (1); Step B: filling with powdered foam glue: calculating the amount of powdered foam glue (3) to be filled according to the foaming coefficient of 0.5 to 3 and the volume of the curved honeycomb (2), and pouring the powdered foam glue (3) into the joint of two adjacent curved honeycombs (2); Step C: placing a pressure-boosting block, laying a layer of peelable cloth (4) and a layer of isolation film (5) on the surface of the curved honeycomb (2) in sequence, and placing at least one pressure-boosting block (6) at the joint of two curved honeycombs (2); Step D: Packaging, laying a layer of air-permeable felt (7) and a layer of vacuum bag (8) on the pressurizing block (6) in sequence for packaging, evacuating the vacuum after packaging and performing a sealing and leak detection inspection; Step E: Curing: sending the packaged honeycomb parts and tooling into the autoclave for curing and molding, and demolding to obtain the honeycomb parts after exiting the autoclave.

[0008] Preferably, in step A, the specific steps of positioning and paving the honeycomb are: projecting a paving area onto the concave forming surface of the curved honeycomb forming tool (1) by a laser projector, and positioning and paving a plurality of curved honeycombs (2) in the paving area in sequence.

[0009] Preferably, the specific steps of step B, filling the powdered foam glue, are: using a V-shaped funnel to slowly pour the powdered foam glue (3) along the wall of the curved honeycomb (2) into the joint of two adjacent positioned and paved curved honeycombs (2).

[0010] Preferably, in step B, the calculation formula for the powdered foam glue filling amount (9) is as follows: m = shρa / c; Wherein, m: powdered foam filling amount (9); s: honeycomb surface area; h: honeycomb height (10); ρ: foam density; a: foaming coefficient; c: foam expansion rate.

[0011] Preferably, in step C, pressure blocks (6) are placed on both sides of the joint of two curved honeycombs (2) filled with powdered foam glue (3) to prevent the powdered foam glue (3) from bulging at the joint.

[0012] Preferably, in step E, during the curing process, the vacuum is -20 kPa to -65 kPa, and the curing temperature is 120 min to 180 min.

[0013] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention aims to propose a new process method for directional and controllable splicing of large-sized curved honeycombs, which realizes uniform splicing and high foaming degree of curved honeycombs by filling powdered foaming glue; and realizes directional controllable splicing height and splicing area of ​​curved honeycombs by quantifying the foaming coefficient; 2. The process method of large-size curved honeycomb directional controllable splicing of the present invention has a simple operation process and good molding quality after curing, that is, the surface of the splicing joint is flat and the quality is good after curing; at the same time, it can avoid material waste and reduce the cost of parts manufacturing, which has important engineering application significance. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of a process method for directional and controllable splicing of a large-size curved honeycomb provided by the present invention; Figure 2 It is a schematic diagram of the height of the powdered foaming glue filling amount provided by the present invention.

[0015] In the figure: 1. curved honeycomb forming tooling; 2. curved honeycomb; 3. powdered foam glue; 4. peelable cloth; 5. isolation film; 6. pressurizing block; 7. breathable felt; 8. vacuum bag; 9. powdered foam glue filling amount; 10. honeycomb height. DETAILED DESCRIPTION

[0016] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. The advantages and features of the present invention will become more apparent from the following description and claims. It should be noted that the drawings are in very simplified form and in non-precise proportions, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention.

[0017] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0018] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0019] In addition, the features, operations, and characteristics described in the specification can be combined in any appropriate manner to form various embodiments. Similarly, the steps or actions described in the method can also be adjusted in order in a manner that can be easily seen by those skilled in the art. Therefore, the various sequences in the specification and drawings are only for the purpose of describing a certain embodiment, and are not necessarily such sequences, unless otherwise stated that a certain sequence must be followed. Example

[0020] The present invention provides a process for directional and controllable splicing of large-size curved honeycombs, please refer to Figure 1 , including the following steps: Step A: Positioning and paving the honeycomb: pre-cleaning the curved honeycomb forming tool 1 with a mold release agent, and then positioning and paving a plurality of curved honeycombs 2 on the concave forming surface of the curved honeycomb forming tool 1; Step B: Filling with powdered foam glue: Calculate the filling amount of the powdered foam glue 3 according to the foaming coefficient of 1.5 and the volume of the curved honeycomb 2, and pour the powdered foam glue 3 into the joint of two adjacent curved honeycombs 2; Step C: placing a boosting block, laying a layer of peelable cloth 4 and a layer of isolation film 5 on the surface of the curved honeycomb 2 in sequence, and placing a boosting block 6 on both sides of the joint of the two curved honeycombs 2; Step D: Packaging, laying a layer of air-permeable felt 7 and a layer of vacuum bag 8 on the booster block 6 in sequence for packaging, and after packaging, evacuating the air and performing a sealing leak test; Step E: Curing, sending the packaged honeycomb parts and tooling into the autoclave for curing and molding, vacuuming to -34kpa, and curing temperature for 180min; demolding after taking out of the can to obtain the honeycomb parts.

[0021] Specifically, the specific steps of positioning and paving the honeycomb are: a paving area is projected on the concave forming surface of the curved honeycomb forming tool 1 by a laser projector, and a plurality of curved honeycombs 2 are positioned and paved in the paving area in sequence.

[0022] Specifically, the specific steps of filling the powdered foam glue are: using a V-shaped funnel to slowly pour the powdered foam glue 3 along the wall of the curved honeycomb 2 into the joint of two adjacent positioned and paved curved honeycombs 2 .

[0023] Furthermore, the calculation formula of the powdered foam filling amount 9 is as follows: m = shρa / c; Wherein, m: powdered foam filling amount 9; s: honeycomb surface area; h: honeycomb height 10; ρ: foam density; a: foaming coefficient; c: foam expansion rate.

[0024] Specifically, pressure blocks 6 are placed on both sides of the joint of two curved honeycombs 2 filled with powdered foam glue 3 to prevent the powdered foam glue 3 from bulging at the joint.

[0025] The above description is only a description of the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention. Any changes or modifications made by a person skilled in the art in the field of the present invention based on the above disclosure shall fall within the scope of protection of the claims.

Claims

1. A process for directional and controllable splicing of large-size curved honeycombs, characterized in that: The steps include: Step A: Positioning and paving the honeycomb: pre-cleaning the curved honeycomb forming tool (1) with a mold release agent, and then positioning and paving a plurality of curved honeycombs (2) on the concave forming surface of the curved honeycomb forming tool (1); Step B: filling with powdered foam glue: calculating the amount of powdered foam glue (3) to be filled according to the foaming coefficient of 0.5 to 3 and the volume of the curved honeycomb (2), and pouring the powdered foam glue (3) into the joint of two adjacent curved honeycombs (2); Step C: placing a pressure-boosting block, laying a layer of peelable cloth (4) and a layer of isolation film (5) on the surface of the curved honeycomb (2) in sequence, and placing at least one pressure-boosting block (6) at the joint of two curved honeycombs (2); Step D: Packaging, laying a layer of air-permeable felt (7) and a layer of vacuum bag (8) on the pressurizing block (6) in sequence for packaging, evacuating the vacuum after packaging and performing a sealing leak test; Step E: Curing: sending the packaged honeycomb parts and tooling into the autoclave for curing and molding, and demolding to obtain the honeycomb parts after exiting the autoclave.

2. A process for directional and controllable splicing of large-size curved honeycombs as claimed in claim 1, characterized in that: Step A, the specific steps of positioning and paving the honeycomb are: projecting a paving area on the concave molding surface of the curved honeycomb molding tool (1) by a laser projector, and positioning and paving a plurality of curved honeycombs (2) in the paving area in sequence.

3. A process for directional and controllable splicing of large-size curved honeycombs as claimed in claim 1, characterized in that: Step B, the specific steps of filling the powdered foam glue are: using a V-shaped funnel to slowly pour the powdered foam glue (3) along the wall of the curved honeycomb (2) into the joint of two adjacent positioned and laid curved honeycombs (2).

4. A process for directional and controllable splicing of large-size curved honeycombs as claimed in claim 1, characterized in that: Step B, the calculation formula of the powdered foam glue filling amount (9) is as follows: m = shρa / c; Wherein, m: powdered foam filling amount (9); s: honeycomb surface area; h: honeycomb height (10); ρ: foam density; a: foaming coefficient; c: foam expansion rate.

5. The process for directional and controllable splicing of large-size curved honeycombs according to claim 1, characterized in that: Step C, placing pressure blocks (6) on both sides of the joint of two curved honeycombs (2) filled with powdered foam glue (3) to prevent the powdered foam glue (3) from bulging at the joint.

6. A process for directional and controllable splicing of large-size curved honeycombs as claimed in claim 1, characterized in that: Step E, curing process, vacuum -20kPa ~ -65kPa, curing temperature 120min ~ 180min.

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