Composite material winding container surface bearing boss system and preparation method

Abstract

The invention provides a composite material winding container surface bearing boss system and a preparation method. The composite material winding container surface bearing boss system comprises a metal lining, a bearing boss, a local reinforcing fiber layer and a local pressure-bearing winding layer. The bearing boss is bonded with the metal lining and is reinforced by a local reinforcing fiber layer and a local pressure-bearing winding layer; the local reinforcing fiber layer and the local pressure-bearing winding layer are both of a pressure-bearing fiber winding structure and are laid alternately. The defect that a bearing boss cannot be arranged at any position is overcome, the function that a bearing supporting point can be arranged on the surface of the composite material winding pressure container is achieved, and the problem that the surface of the composite material winding container cannot provide supporting and force bearing points for system assemblies such as a heat screen, a pipeline and a valve is solved. And a better solution is provided for optimized layout and reasonable structural design of the system.

Description

Technical Field

[0001] The present invention belongs to the technical field of manufacturing aerospace lightweight composite wound pressure vessels, and in particular, relates to a surface bearing boss system for a composite wound vessel and a preparation method thereof. Background Art

[0002] In the field of aerospace pressure vessels, composite wrapped pressure vessels have irreplaceable advantages due to the development requirements of lightweight and high reliability. In recent years, composite pressure vessels such as high-pressure gas cylinders and propellant tanks have been widely used in aerospace propulsion systems. Spacecraft propulsion systems generally have compact structural layouts, complex internal structures, and high requirements for mechanical environmental adaptability. Therefore, in the structural optimization design, there has always been a problem of installing or fixing components such as heat shields, pipelines, cables, and valves on the surface of larger pressure vessels. On the one hand, it can make full use of the structural optimization system structural layout, and on the other hand, it can greatly reduce the design weight and complexity of the assembly structure. The above scheme can be implemented on pressure vessels with metal shells, but it is more difficult to implement on the surface of pressure vessels wrapped with composite materials.

[0003] At present, composite pressure vessels are generally manufactured using the fiber winding process. However, due to the particularity of the fiber winding process, it is generally required that the outer surface of the lining has a smooth transition, which is beneficial to the strength of the pressure-bearing fiber layer and the fiber load-bearing coefficient. The nozzle structure of the two poles of the wound pressure vessel can be solved by combining the lining wall thickness reinforcement with the setting of pole hole winding. However, the scheme of setting a load-bearing boss at any position is difficult to implement. On the one hand, it is worried that it will affect the pressure-bearing and sealing performance of the container, and on the other hand, it has high requirements for the implementation process.

[0004] Related prior arts include: high-pressure composite container (patent document CN109140223B). This patent document discloses a high-pressure composite container, which shares 1 / 3 of the extrusion force from the reinforcement layer by arranging a boss on the metal end, so that other parts of the metal end can be subjected to less extrusion force, avoiding the generation of large stress on the metal end. However, the structure of this technical solution is relatively complex, and the position of the bearing boss is set in a single position. There is only the metal end and it depends on the structure of the metal end itself, and the bearing boss cannot be set at any position.

[0005] In view of the problems existing in the prior art, the present invention provides a composite material wrapped container surface bearing boss system and a preparation method thereof. Summary of the invention

[0006] In view of the defects in the prior art, the object of the present invention is to provide a composite material wrapped container surface bearing boss system and a preparation method thereof.

[0007] A composite material wrapped container surface bearing boss system provided by the present invention comprises: a metal liner, a bearing boss, an adhesive layer, a local reinforcing fiber layer and a local pressure-bearing wrapping layer;

[0008] The bearing boss is bonded to the metal liner and reinforced with a local reinforcing fiber layer and a local pressure-bearing winding layer;

[0009] The local reinforcing fiber layer and the local pressure-bearing winding layer are both pressure-bearing fiber winding structures, which are laid alternately and cured integrally with the bonding layer.

[0010] Preferably, the metal liner is an integrally formed structure or a welded structure, and is spherical or spherical-cylindrical in shape to match the shape of the pressure vessel wall; the bottom surface of the bearing boss is contoured to maintain consistency with the curved surface of the metal liner.

[0011] Preferably, the local reinforcing fiber layer and the local pressure-bearing winding layer are both pressure-bearing fiber winding structures, and are laid alternately in single or multiple layers;

[0012] The local reinforcement fiber layer is a fiber cloth, and the material is consistent with the local pressure-bearing winding layer; according to the position of the bearing boss and the main force direction, an axial orthogonal, 45° orthogonal or transverse reinforcement method can be selected;

[0013] The pressure bearing capacity of the local pressure-bearing winding layer meets the requirements of the internal pressure bearing, dynamic stiffness and deformation of the pressure vessel.

[0014] Preferably, the pressure vessel comprises: a head camber surface and a column segment camber surface; the bearing boss can be arranged on the head camber surface or the column segment camber surface of the pressure vessel, and the arrangement density of the bearing bosses on the same height band is determined according to the diameter of the pressure vessel at the location and is evenly distributed; the protruding direction of the bearing boss is the normal direction of the head camber surface or the column segment camber surface, and the inclination angle is not greater than 30 degrees.

[0015] Preferably, the bearing boss is made of metal and is an integrally formed structure or a welded structure.

[0016] The bearing boss adopts a base suction cup structure, and the suction cup is provided with a tightening groove and a glue overflow hole;

[0017] The reinforcement area of ​​the local reinforcing fiber layer and the local pressure-bearing winding layer must cover the area of ​​the bearing boss suction cup.

[0018] Preferably, the number of tightening grooves is 2 to 6; the diameter of the glue overflow hole is φ1~2mm, and the number of glue overflow holes is evenly distributed according to the size of the suction cup; the size of the suction cup is determined according to the load-bearing size, the alternating winding thickness of the local reinforcing fiber layer and the local pressure-bearing winding layer at the location, and the diameter of the suction cup is three to seven times the diameter of the load-bearing boss.

[0019] A method for preparing a composite material winding container surface bearing boss system according to the present invention comprises:

[0020] Step S1: design and manufacture of metal lining;

[0021] Step S2: designing process parameters for the local pressure-bearing winding layer according to the strength design requirements of the pressure vessel of the wound composite material, and determining the process parameters of the local pressure-bearing winding layer;

[0022] Step S3: designing and manufacturing the bearing boss according to the bearing load requirement and the installation position;

[0023] Step S4: designing a local reinforcement fiber layer according to the installation position and shape of the bearing boss;

[0024] Step S5: performing force and load analysis and verification of the load-bearing boss based on the design status of step S3 and step S4;

[0025] Step S6: bonding and pre-curing the bearing boss and the metal lining;

[0026] Step S7: Arrange the local reinforcing fiber layer and the local pressure-bearing winding layer and solidify them with the adhesive layer structure.

[0027] Preferably, the step S3 is implemented by winding a local reinforcing fiber layer and a local pressure-bearing winding layer and then heightening them through threaded connection for higher bearing boss design requirements;

[0028] The curing temperature in step S7 is 60° C. to 130° C., and the curing time is 6 hours to 16 hours.

[0029] Preferably, step S5 analyzes and verifies the stress on the root position, local reinforcing fiber layer, local pressure-bearing winding layer, adhesive layer and other positions of the bearing boss under the load state, as well as the stress on the fibers around the bearing boss under the pressure state, to meet the strength design criteria.

[0030] Preferably, the adhesive layer is evenly applied, the thickness of the adhesive layer is 0.05-0.4 mm, and the bearing boss and the metal lining bonding surface are degreased and polished before bonding; after application, a pre-curing treatment is performed, and the pre-curing strength is 20%-50% of the strength after curing.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] 1. The present invention overcomes the deficiency in the prior art that a bearing boss cannot be set at any position, and realizes the function of setting a bearing support point at any position on the surface of a composite material wrapped pressure vessel;

[0033] 2. The present invention solves the problem that the surface of the composite material wrapped around the container cannot provide support and load-bearing points for system components such as heat insulation screens, pipelines, and valves, and provides a better solution for system optimization layout and reasonable structural design. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0035] Figure 1 It is a schematic diagram of the installation of the bearing boss system of the composite material wrapped around the surface of the container of the present invention.

[0036] Figure 2 for Figure 1 Schematic diagram of the local area along the normal direction of the pressure vessel wall at point A.

[0038] Figure 3 It is a schematic diagram of the bearing boss structure of the present invention.

[0039] Figure 4 It is a schematic diagram of local axial orthogonal fiber reinforcement of the present invention.

[0040] Figure 5 It is a schematic diagram of local 45° orthogonal fiber reinforcement of the present invention.

[0041] Figure 6 This is a schematic diagram of local transverse fiber reinforcement of the present invention.

[0042] Figure 7 It is a schematic diagram of the structure of the present invention.

[0043] The figure shows:

[0044] DETAILED DESCRIPTION

[0045] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several changes and improvements can also be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0046] like Figures 1 to 3 As shown, an embodiment of the present invention provides a composite material wrapped around a container surface bearing boss system, comprising: a metal liner 1, a bearing boss 5, an adhesive layer 2, a local reinforcing fiber layer 4 and a local pressure-bearing winding layer 3;

[0047] The bearing boss 5 is bonded to the metal lining 1 and reinforced with a local reinforcing fiber layer 4 and a local pressure-bearing winding layer 3; both the local reinforcing fiber layer 4 and the local pressure-bearing winding layer 3 are pressure-bearing fiber winding structures, which are laid alternately and cured integrally with the bonding layer 2.

[0048] Furthermore, the metal lining 1 is an integrally formed structure or a welded structure, which is a spherical or spherical column that matches the shape of the wall of the pressure vessel 9, and has performance and functions such as sealing, interface, and stiffness; the local reinforcing fiber layer 4 and the local pressure-bearing winding layer 3 are both pressure-bearing fiber winding structures, which can be laid alternately. According to specific load-bearing and reinforcement requirements, multiple layers of local reinforcing fiber layers 4 and multiple layers of local pressure-bearing winding layers 3 can be laid alternately; the pressure vessel 9 includes: a head camber 200 and a column segment camber 300; the bearing boss 5 can be set on the head camber 200 or the column segment camber 300 of the pressure vessel 9, and the height of the bearing boss 5 should not exceed High, too high a boss height is not conducive to the avoidance of the pressure-bearing winding fiber, affecting the winding tension parameters; and the number of bearing bosses 5 on the same height band should not be too many, too many bearing bosses will lead to too dense arrangement, affecting the winding direction of the pressure-bearing fiber, the density of the bearing boss 5 arrangement is determined by the diameter of the pressure vessel 9 at the location, and is generally evenly distributed; the protruding direction of the bearing boss 5 is preferably the normal direction of the head arc surface 200 or the column segment arc surface 300, and it is allowed to be adjusted within a small inclination range, and the inclination range is generally not more than 30 degrees; further, the bottom surface of the bearing boss 5 is contoured to maintain the consistency of the curved surface with the surface of the metal lining 1. The bearing boss 5 is made of aluminum alloy, titanium alloy, stainless steel and other metals, and is an integrated molding structure or a welded structure. The integrated molding is generally machined after integrated spinning. The welding molding can be selected according to the material selection. TIG welding, friction welding, electron beam welding and other methods, after molding, it is required to have sealing, interface, rigidity and other performance and functions.

[0049] Furthermore, if Figure 4 As shown, the bearing boss 5 adopts a base suction cup structure, which is conducive to improving its connection strength. The suction cup is provided with a tightening groove 6 and a glue overflow hole 7. The tightening groove 6 is convenient for tightening, and the glue overflow hole 7 is a hole structure that facilitates glue overflow; further, the number of the tightening grooves 6 is generally 2 to 6; the diameter of the glue overflow hole 7 is generally φ1~2mm, and the number of the glue overflow holes 7 is evenly distributed according to the size of the suction cup. The size of the suction cup is determined according to the bearing size, the alternating winding thickness of the local reinforcing fiber layer 4 and the local pressure-bearing winding layer 3 at the location, and it is recommended that the diameter of the suction cup is three to seven times the diameter of the bearing boss 5, and the thickness of the suction cup is as thin as possible.

[0050] Furthermore, if Figures 5 to 7As shown, the local reinforcing fiber layer 4 is a fiber cloth, and the material is consistent with the local pressure-bearing winding layer 3; according to the position of the bearing boss 5 and the main force direction, the reinforcement methods such as axial orthogonal, 45-degree orthogonal and transverse can be selected; the pressure bearing capacity of the local pressure-bearing winding layer 3 meets the requirements of the internal pressure bearing, dynamic stiffness and deformation of the pressure vessel 9; the reinforcement area of ​​the local reinforcing fiber layer 4 and the local pressure-bearing winding layer 3 must cover the area of ​​the suction cup of the bearing boss 5. Further, the adhesive layer 2 uses an adhesive with good toughness and moderate strength; further, the adhesive layer 2, the reinforcing fiber layer 4 and the pressure-bearing winding layer 3 are solidified as a whole.

[0051] Specifically, an embodiment of the present invention further provides a method for preparing the composite material wrapped container surface bearing boss system of the present invention; comprising:

[0052] Step S1: designing and manufacturing the metal lining 1;

[0053] Step S2: designing process parameters for the pressure-bearing winding layer 3 according to the strength design requirements of the pressure vessel 9 of the winding composite material, and determining the process parameters of the pressure-bearing winding layer 3;

[0054] Step S3: designing and manufacturing the bearing boss 5 according to the bearing load requirement and the installation position;

[0055] Step S4: designing a local reinforcement fiber layer according to the installation position and shape of the bearing boss 5;

[0056] Step S5: Based on the design status of step S3 and step S4, the force and load analysis and verification of the bearing boss 5 are performed;

[0057] Step S6: bonding and pre-curing the bearing boss 5 and the metal lining 1;

[0058] Step S7: Arrange the local reinforcing fiber layer 4 and the local pressure-bearing winding layer 3 and solidify them with the adhesive layer 2 structure.

[0059] Furthermore, the height design of the bearing boss 5 in step S3 should not be too high; the design requirements for a higher bearing boss 5 can be achieved by winding the local reinforcing fiber layer 4 and the local pressure-bearing winding layer 3 and then heightening it through threaded connection. Furthermore, step S5 analyzes and verifies the stress of the root position of the bearing boss 5, the local reinforcing fiber layer 4, the local pressure-bearing winding layer 3, the bonding layer 2 and other positions under the bearing state, as well as the stress of the fibers around the bearing boss 5 under the pressure state, to meet the strength design criteria; further, the bonding layer in step S6 should use an adhesive with good toughness and moderate strength, and the bonding layer 2 is required to be evenly applied to avoid electrochemical corrosion between dissimilar metals; the thickness of the bonding layer 2 is generally required to be 0.05 to 0.4 mm, and the bonding surface of the bearing boss 5 and the metal lining 1 is required to be degreased and polished before bonding. After coating, pre-curing treatment is carried out, and the pre-curing strength is 20% to 50% of the strength after curing to avoid movement of the bearing boss during the winding process. Furthermore, the curing in step S7 can achieve integrated curing of the adhesive layer 2, the local reinforcing fiber layer 4 and the local pressure-bearing winding layer 3. The curing system should take into account the curing of the adhesive layer 2 with glue and the winding layer composed of the local reinforcing fiber layer 4 and the local pressure-bearing winding layer 3 with resin. The commonly used temperature is 60°C to 130°C, and the curing time is 6 hours to 16 hours to ensure that the adhesive layer 2 and the resin are fully cured.

[0060] In summary, the embodiments of the present invention provide a system and a preparation method for a surface bearing boss of a composite material wrapped container, which addresses the installation requirements of the surface bearing boss of a composite material wrapped pressure vessel, overcomes the deficiency in the prior art that bearing bosses cannot be set at arbitrary positions, and realizes the function of setting bearing support points on the surface of a composite material wrapped pressure vessel, thereby solving the problem that the surface of a composite material wrapped container cannot provide support and load-bearing points for system components such as thermal insulation screens, pipelines, and valves, and provides a better solution for system optimization layout and reasonable structural design.

[0061] In the description of the present application, it should be understood that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0062] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. In the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. A composite material wrapped around a container surface bearing boss system, characterized in that: include: A metal lining (1), a bearing boss (5), an adhesive layer (2), a local reinforcing fiber layer (4) and a local pressure-bearing winding layer (3); The bearing boss (5) is bonded to the metal lining (1) and is reinforced with a local reinforcing fiber layer (4) and a local pressure-bearing winding layer (3); The local reinforcing fiber layer (4) and the local pressure-bearing winding layer (3) are both pressure-bearing fiber winding structures, which are laid alternately and are cured integrally with the bonding layer (2).

2. The composite material wrapped container surface bearing boss system according to claim 1, characterized in that: The metal liner (1) is an integrally formed structure or a welded structure, and is spherical or spherical-cylindrical in shape to match the wall shape of the pressure vessel (9); the bottom surface of the bearing boss (5) is contoured to maintain consistency with the curved surface of the metal liner (1).

3. The composite material wrapped container surface bearing boss system according to claim 1, characterized in that: The local reinforcing fiber layer (4) and the local pressure-bearing winding layer (3) are both pressure-bearing fiber winding structures, and are laid alternately in single or multiple layers; The local reinforcement fiber layer (4) is a fiber cloth, and the material is consistent with that of the local pressure-bearing winding layer (3); according to the position of the bearing boss (5) and the main force direction, an axial orthogonal, 45° orthogonal or transverse reinforcement method can be selected; The pressure bearing capacity of the local pressure-bearing winding layer (3) meets the requirements of the pressure vessel (9) for internal pressure bearing, dynamic stiffness and deformation, etc.

4. The composite material wrapped container surface bearing boss system according to claim 1, characterized in that: The pressure vessel (9) comprises: a head camber (200) and a column segment camber (300); the bearing boss (5) can be arranged on the head camber (200) or the column segment camber (300) of the pressure vessel (9); the arrangement density of the bearing bosses (5) on the same height band is determined according to the diameter of the pressure vessel (9) at the location and is evenly distributed; the protruding direction of the bearing bosses (5) is in the normal direction of the head camber (200) or the column segment camber (300) at an angle not greater than 30 degrees.

5. The composite material wrapped container surface bearing boss system according to claim 3, characterized in that: The bearing boss (5) is made of metal and is an integrally formed structure or a welded structure; The bearing boss (5) adopts a base suction cup structure, and the suction cup is provided with a tightening groove (6) and a glue overflow hole (7); The reinforcement area of ​​the local reinforcing fiber layer (4) and the local pressure-bearing winding layer (3) must cover the area of ​​the suction cup of the bearing boss (5).

6. The composite material wrapped container surface bearing boss system according to claim 5, characterized in that: The number of the tightening grooves (6) is 2 to 6; the diameter of the glue overflow hole (7) is φ1 to 2 mm, and the number of the glue overflow holes (7) is evenly distributed according to the size of the suction cup; the size of the suction cup is determined according to the load-bearing size and the alternating winding thickness of the local reinforcing fiber layer (4) and the local pressure-bearing winding layer (3) at the location, and the diameter of the suction cup is three to seven times the diameter of the load-bearing boss (5).

7. A method for preparing the composite material wrapped around the surface bearing boss system of a container according to claims 1 to 6, characterized in that: include: Step S1: design and manufacture of metal lining (1); Step S2: designing process parameters for the local pressure-bearing winding layer (3) according to the strength design requirements of the pressure vessel (9) of the wound composite material, and determining the process parameters of the local pressure-bearing winding layer (3); Step S3: designing and manufacturing the bearing boss (5) according to the bearing load requirement and the installation position; Step S4: designing a local reinforcement fiber layer according to the installation position and shape of the bearing boss (5); Step S5: Based on the design conditions of step S3 and step S4, the load-bearing analysis and verification of the load-bearing boss (5) are performed; Step S6: bonding and pre-curing the bearing boss (5) and the metal lining (1); Step S7: Arrange the local reinforcing fiber layer (4) and the local pressure-bearing winding layer (3) and solidify them with the adhesive layer (2).

8. The method for preparing the bearing boss system of the composite material wound container surface according to claim 7, characterized in that: The step S3 is implemented by winding a local reinforcing fiber layer (4) and a local pressure-bearing winding layer (3) and then heightening them through threaded connection in order to meet the design requirements of a higher bearing boss (5); The curing temperature in step S7 is 60° C. to 130° C., and the curing time is 6 hours to 16 hours.

9. The method for preparing a bearing boss system on the surface of a composite material wound container according to claim 7, characterized in that: The step S5 analyzes and verifies the stress on the root position of the bearing boss (5), the local reinforcing fiber layer (4), the local pressure-bearing winding layer (3), the bonding layer (2) and other positions under the bearing state, as well as the stress on the fibers around the bearing boss (5) under the pressure state, to meet the strength design criteria.

10. The method for preparing a bearing boss system on the surface of a composite material wound container according to claim 7, characterized in that: The adhesive layer (2) is evenly applied, and the thickness of the adhesive layer (2) is 0.05 to 0.4 mm. Before bonding, the bonding surfaces of the bearing boss (5) and the metal lining (1) are degreased and polished; after application, a pre-curing treatment is performed, and the pre-curing strength is 20% to 50% of the strength after curing.

Images