A kind of spherocylindrical storage tank assembly structure and assembly method

Abstract

This invention provides an assembly structure and method for a spherical tank, employing a combination of fixed support at the tank's waist with a planar flange and a simply supported top end, thus achieving freedom of movement along the tank's length. A planar flange is added to the waist of the spherical tank, which is then fixedly connected to the lower compartment of the spacecraft's transverse main structure, connecting the spherical tank to the spacecraft cabin. The simply supported top end installation involves an end cap bushing assembly fitted onto the top end of the spherical tank. This end cap bushing assembly connects to the upper compartment of the spacecraft's transverse main structure, constraining the lateral freedom of the spherical tank's top, while allowing for longitudinal freedom. This assembly structure offers advantages such as simple structure, light weight, ease of operation, and low assembly and structural internal stress.

Description

Technical Field

[0001] This invention relates to the overall assembly design of spherical tanks for spacecraft, specifically to an assembly structure and assembly method for spherical tanks. Background Technology

[0002] The spherical propellant tanks used in spacecraft often employ a planar double-flange, end-fixed assembly structure, which has numerous drawbacks:

[0003] a) The assembly structure is over-constrained, making it difficult to avoid assembly stress, which reduces the structural load-bearing capacity;

[0004] b. Due to over-constraint, there will inevitably be an installation gap on the flange face, which needs to be eliminated by means of gaskets, resulting in complex structure and difficult operation;

[0005] c. Since the storage tank needs to be pressurized after installation, it can generally reach an internal pressure of MPa. The storage tank undergoes large axial deformation, which further increases the internal stress of the structure.

[0006] To avoid the above situation, a common method is to retain only one flat flange and allow the other to have axial freedom. For example, the tank can be assembled by using a flat flange at one end and a tie rod at the other end. Although the tie rod can achieve freedom in the length direction (i.e., axial direction) of the tank and solve the shortcomings of the above-mentioned flat double flange fixed-end assembly structure, it adds tie rod structure, resulting in structural complexity and increased weight. Summary of the Invention

[0007] The purpose of this invention is to provide a spherical tank assembly structure and assembly method, thereby achieving freedom in the length direction of the tank.

[0008] To achieve the above objectives, the present invention provides a spherical tank assembly structure, which adopts an installation form that combines fixed support at the waist of the tank with a flat flange and simple support at the top end of the tank. The simple support installation form at the top end of the tank has a degree of freedom of movement along the length of the tank.

[0009] The aforementioned spherical tank assembly structure includes the following: A planar flange is added to the waist of the spherical tank, and the waist of the spherical tank is fixedly connected to the lower compartment of the transverse main structure of the spacecraft body through this planar flange, thus connecting the spherical tank to the spacecraft body; the top end of the tank is simply supported, with an end cap bushing assembly fitted onto the top end of the spherical tank. This end cap bushing assembly is connected to the upper compartment of the transverse main structure of the spacecraft body, constraining the transverse degree of freedom of the top of the spherical tank, but the top of the spherical tank has a longitudinal degree of freedom.

[0010] In the aforementioned spherical tank assembly structure, the end cover bushing assembly is provided with pin holes, and pin holes are drilled on the upper tank plate to install shear positioning pins.

[0011] In the above-mentioned spherical tank assembly structure, the end cover bushing assembly includes an end cover and a bushing. The bushing is fitted onto the top end of the spherical tank, the end cover is fitted onto the bushing, the bushing is connected to the end cover, and the end cover is connected to the upper compartment plate.

[0012] In the above-mentioned spherical tank assembly structure, the bushing is made of a material with lubricating properties.

[0013] In the aforementioned spherical tank assembly structure, the end cover includes a first annular cylinder and a first flange. The first flange is disposed at one end of the first annular cylinder. The first flange is provided with a bushing mounting hole, an upper compartment plate mounting hole, and a pin hole. The bushing mounting hole is used to connect the bushing, the upper compartment plate mounting hole is used to connect the upper compartment plate, and the pin hole is used to install a shear positioning pin. The upper compartment plate mounting hole is an oblong hole.

[0014] In the above-mentioned spherical tank assembly structure, the bushing includes a second annular column and a second flange. The second flange is disposed at one end of the second annular column, and the second flange is provided with an end cover mounting hole for connecting an end cover.

[0015] In the above-mentioned spherical tank assembly structure, the inner diameter of the bushing and the outer diameter of the top end of the spherical tank are fitted with a clearance; the outer diameter of the bushing and the inner diameter of the end cover are fitted with a small clearance; the end cover is placed in the through hole of the upper compartment plate and connected by fasteners, and the outer diameter of the end cover and the through hole of the upper compartment plate are fitted with a clearance.

[0016] In the aforementioned spherical cylindrical tank assembly structure, a threaded through hole is provided at the top end of the spherical cylindrical tank.

[0017] Another technical solution provided by the present invention is a method for assembling a spherical tank, comprising: adding a flat flange to the waist of the spherical tank; during assembly, fixing the flat flange of the waist of the spherical tank to the lower compartment plate; installing the upper compartment plate onto the transverse main structure of the spacecraft body, ensuring that the top end of the spherical tank is inserted into the through hole of the upper compartment plate; fitting a bushing into the end cover, bonding the bushing and the end cover with adhesive, and connecting the bushing and the end cover with a third fastener to obtain an end cover bushing assembly; inserting the end cover bushing assembly into the through hole of the upper compartment plate, with the top end of the spherical tank fitted into the end cover bushing assembly, and connecting the end cover bushing assembly and the upper compartment plate with a second fastener; drilling pin holes on the upper compartment plate according to the pin holes on the end cover bushing assembly, and then installing shear positioning pins.

[0018] Compared with the prior art, the beneficial technical effects of the present invention are:

[0019] The spherical tank assembly structure and assembly method of the present invention adopts an installation form that combines the fixed support of the tank waist plane flange and the simple support of the tank top end (with the freedom of movement along the tank length direction). This realizes that the tank top end is not constrained to deform along the axial direction, and the end is free along the tank axis, thereby reducing assembly stress and internal structural stress.

[0020] The spherical cylindrical tank assembly structure and assembly method of the present invention add a flat flange to the waist of the spherical cylindrical tank to realize the connection between the spherical cylindrical tank and the spacecraft cabin; the end cover bushing assembly is designed to constrain the lateral degree of freedom of the top of the spherical cylindrical tank, but the top of the spherical cylindrical tank has axial degree of freedom; the spherical cylindrical tank is directly connected to the main structure of the spacecraft, and the assembly structure is simple, easy to operate, and lightweight;

[0021] The spherical tank assembly structure and assembly method of the present invention take into account that the top end of the tank is a free end and will experience friction and wear. A bushing is fitted on the outside of the top end of the tank. The main functions of the bushing are positioning, wear reduction, lubrication and buffering. An end cover is installed on the outside of the bushing. The main functions of the end cover are connection, force transmission and load bearing. The end cover and the main structure of the tank are assembled by fasteners. In order to solve the problem of over-positioning in the transverse direction of the tank, the through hole between the end cover and the main structure of the tank is designed as a clearance fit. At the same time, the upper tank plate mounting hole on the end cover is designed as an oblong hole to facilitate assembly with the through hole of the main structure of the tank.

[0022] The spherical cylindrical tank assembly structure and assembly method of the present invention take into account that the end cap is assembled with the main structure of the cabin by fasteners. Because the axial dimension of the spherical cylindrical tank is too long, the top end of the tank will be subjected to a large lateral shear force during the active phase of launch. The shear force provided by the fastener is determined by its friction. In order to increase the assembly reliability, several pins are made on the end cap, which can bear part of the lateral shear force and at the same time play the role of repeated installation and positioning, and quickly restore the assembly accuracy. Attached Figure Description

[0023] The spherical tank assembly structure and assembly method of the present invention are given by the following embodiments and figures.

[0024] Figure 1 This is a cross-sectional view of the spherical tank assembly structure according to an embodiment of the present invention.

[0025] Figure 2 This is a front view of the spherical tank assembly structure according to an embodiment of the present invention.

[0026] Figure 3 This is a schematic diagram of the end cap structure in an embodiment of the present invention.

[0027] Figure 4 This is a schematic diagram of the bushing structure in an embodiment of the present invention.

[0028] Figure 5 This is a schematic diagram of the end cap bushing assembly in an embodiment of the present invention. Detailed Implementation

[0029] The following will combine Figures 1-5 The assembly structure and assembly method of the spherical tank of the present invention will be described in further detail.

[0030] Figure 1 The figure shown is a cross-sectional view of the spherical tank assembly structure according to an embodiment of the present invention, wherein (b) is a partial enlarged view of section I in (a); Figure 2 The image shown is a front view of the spherical tank assembly structure according to an embodiment of the present invention.

[0031] like Figure 1 and Figure 2 As shown, the spherical tank assembly structure of this embodiment adopts an installation form that combines the fixed support of the tank waist plane flange and the simple support of the tank top end. The simple support installation form of the tank top end has a degree of freedom of movement along the length direction of the tank (i.e., the tank axis, or longitudinal direction).

[0032] Fixed installation method of the waist plate flange of the storage tank: A plate flange is added to the waist of the spherical storage tank 6. The plate flange is fixedly connected to the lower compartment plate 5 of the transverse main structure of the spacecraft for instrument installation by the first fastener 10, so as to realize the connection between the waist of the spherical storage tank and the spacecraft body.

[0033] The tank top end is simply supported and installed in the following manner: The end cover bushing assembly 7 is designed and is fitted on the top end of the spherical tank 6. The end cover bushing assembly 7 is connected to the upper compartment 4 of the transverse main structure of the spacecraft for instrument installation by the second fastener 8, which restricts the transverse (i.e., radial) degree of freedom of the top of the spherical tank, but does not restrict the longitudinal degree of freedom of the top of the spherical tank.

[0034] like Figure 1 As shown, the end cap bushing assembly 7 includes an end cap 1 and a bushing 2. The bushing 2 is fitted onto the top end of the spherical tank 6, and the end cap 1 is fitted onto the bushing 2. The bushing 2 is connected to the end cap 1 by a third fastener 9, and the bushing 2 and the end cap 1 are glued together. The end cap 1 is connected to the upper compartment plate 4 by a second fastener 8. That is, the end cap 1, the bushing 2, and the top end of the spherical tank are nested together. The end cap 1 mainly serves the functions of connection, force transmission, and load bearing, while also solving the problem of lateral over-positioning of the tank during final assembly. The bushing 2 serves the functions of positioning, buffering, and lubrication.

[0035] Preferably, the bushing 2 is made of a material that has a lubricating effect, such as polytetrafluoroethylene.

[0036] Preferably, the top end of the spherical tank 6 is provided with a threaded through hole, which can be used as a hoisting interface for transfer and final assembly.

[0037] Figure 3 The diagram shown is a structural schematic of the end cap in an embodiment of the present invention.

[0038] like Figure 3 As shown, the end cap 1 includes a first annular cylinder 11 and a first flange 12. The first flange 12 is disposed at one end of the first annular cylinder 11. The first flange 12 is provided with a bushing mounting hole 13, an upper compartment plate mounting hole 14 and a pin hole 15. The bushing mounting hole 13 is used to connect the bushing 2, the upper compartment plate mounting hole 14 is used to connect the upper compartment plate 4, and the pin hole 15 is used to install the shear positioning pin 3.

[0039] Preferably, the mounting hole 14 of the upper compartment plate is an oblong hole.

[0040] Figure 4 The figure shown is a schematic diagram of the bushing structure in an embodiment of the present invention.

[0041] like Figure 4 As shown, the bushing 2 includes a second annular cylinder 21 and a second flange 22. The second flange 22 is disposed at one end of the second annular cylinder 21, and the second flange 22 is provided with an end cap mounting hole 23.

[0042] Figure 5 The diagram shown is a schematic diagram of the end cap bushing assembly in an embodiment of the present invention.

[0043] like Figure 5 As shown, the second annular cylinder 21 of the bushing 2 is placed inside the first annular cylinder 11 of the end cap 1, and the second flange 22 of the bushing 2 is supported by the first flange 12 of the end cap 1. The bushing 2 and the end cap 1 are fixedly connected through the end cap mounting hole 23, the bushing mounting hole 13 and the third fastener 9. The outer diameter of the second annular cylinder 21 and the inner diameter of the first annular cylinder 11 are fitted with a small clearance. The outer side wall of the second annular cylinder 21 and the inner side wall of the first annular cylinder 11 are coated with adhesive, that is, they are connected by adhesive bonding.

[0044] like Figure 1 The bushing 2 is fitted onto the top end of the spherical tank. The inner diameter of the second annular cylinder 21 and the outer diameter of the top end of the spherical tank are fitted with a clearance to ensure that the bushing 2 and the end cap 1 can be easily fitted into the top end of the spherical tank after assembly.

[0045] The end cap 1 is placed in the through hole of the upper compartment plate and is connected to the upper compartment plate 4 through the waist-shaped upper compartment plate mounting hole 14 on the first flange 12 and the second fastener 8. The outer diameter of the first annular cylinder 11 and the through hole of the upper compartment plate are fitted with clearance. The upper compartment plate 4 is equipped with pin holes, and the shear positioning pin 3 is connected to the pin hole 15 on the first flange 12 and the pin hole of the upper compartment plate 4.

[0046] In this embodiment, the assembly method of the spherical cylindrical storage tank 6 is as follows:

[0047] During assembly, the waist-shaped flange of the spherical tank 6 is fixed to the lower compartment plate 5 (using the first fastener 10); the upper compartment plate 4 is installed onto the transverse main structure of the spacecraft body, ensuring that the top end of the spherical tank 6 is inserted into the through hole of the upper compartment plate 4; the bushing 2 is fitted into the end cover 1, and the bushing 2 and the end cover 1 are connected by the third fastener 9 to obtain the end cover bushing assembly 7; the end cover bushing assembly 7 is inserted into the through hole of the upper compartment plate 4, and the top end of the spherical tank 6 is fitted into the end cover bushing assembly 7, and the end cover bushing assembly 7 and the upper compartment plate 4 are connected by the second fastener 8; according to the pin hole 15 on the end cover bushing assembly 7, pin holes are drilled on the upper compartment plate 4, and then shear positioning pins 3 are installed.

[0048] Compared to conventional assembly structures, this embodiment adopts an installation method that combines a fixed support at the waist of the spherical tank with a flat flange and a simply supported top end (with a degree of freedom of movement along the tank's axial direction). The lateral load on the top end of the tank is transferred to the upper deck through the end cover bushing assembly. This not only ensures that the top end of the spherical tank is not constrained in axial deformation and is in a free state along the tank's axial direction, reducing assembly stress and internal structural stress, but also achieves a simple assembly structure that is easy to operate and lightweight.

[0049] Furthermore, considering that the top end of the spherical tank is a free end and will experience friction and wear, a bushing is fitted over the top end of the spherical tank. The main functions of this bushing are positioning, lubrication, and cushioning. An end cap is installed over the bushing, and its main functions are connection, force transmission, and load bearing. The end cap and the upper tank plate are assembled using a second fastener. Conventional tank assembly methods using flat flanges at both ends can encounter over-positioning problems. The assembly structure of this embodiment does not have over-positioning problems along the axial direction of the spherical tank. To solve the over-positioning problem along the lateral direction of the spherical tank, this embodiment designs a clearance fit between the end cap and the through hole of the upper tank plate. At the same time, the upper tank plate mounting hole on the end cap flange is designed as an oblong hole to facilitate assembly with the upper tank plate mounting hole. Therefore, the end bushing assembly can effectively constrain the lateral displacement of the spherical tank, while the end cap bushing assembly can ensure that the longitudinal deformation displacement of the top end of the spherical tank is unconstrained.

[0050] Finally, considering that the end cap is assembled to the upper compartment plate mounting holes via the second bolt fastener, and because the axial dimension of the spherical propellant tank is too long, during the active phase of launch, the top end of the spherical propellant tank will be subjected to a large lateral shear force due to the vibration environment transmitted from the rocket to the spacecraft. The shear force provided by the second fastener is determined by its friction. To ensure the stability of the spherical propellant tank under the launch vibration environment and the reliability of the overall assembly, several pin holes are opened on the end cap to install shear-resistant positioning pins. This can help to withstand part of the lateral shear force and also allows for repeated installation and positioning, quickly restoring assembly accuracy.

[0051] In summary, the spherical tank assembly structure of this embodiment has the advantages of simple assembly structure, light weight, easy operation, and low assembly stress and internal structural stress.

[0052] The above-disclosed embodiment is only one specific embodiment of this application, but this application is not limited thereto. Any variations that can be conceived by those skilled in the art should fall within the protection scope of this application.

Claims

1. A spherical cylindrical storage tank assembly structure, characterized in that, The installation method adopts a combination of fixed support at the waist of the tank with a flat flange and simple support at the top end of the tank. The simple support installation method at the top end of the tank has a degree of freedom of movement along the length of the tank. The fixed installation method of the waist plate flange of the tank: A flat flange is added to the waist of the spherical tank. The waist of the spherical tank is fixedly connected to the lower compartment plate of the transverse main structure of the spacecraft body through the flat flange, so as to realize the connection between the spherical tank and the spacecraft body. The tank top end is simply supported and installed in the following manner: an end cover bushing assembly is designed and fitted onto the top end of the spherical tank. The end cover bushing assembly is connected to the upper compartment of the transverse main structure of the spacecraft body, which restricts the transverse degree of freedom of the top of the spherical tank, but the top of the spherical tank has the longitudinal degree of freedom. The end cap bushing assembly is provided with pin holes, and pin holes are drilled on the upper compartment plate to install shear positioning pins. The end cap bushing assembly includes an end cap and a bushing. The bushing is fitted onto the top end of the spherical tank, and the end cap is fitted onto the bushing. The bushing is connected to the end cap, and the end cap is connected to the upper compartment plate. The bushing is made of a material with lubricating properties; The inner diameter of the bushing and the outer diameter of the top end of the spherical tank are fitted with a clearance; the outer diameter of the bushing and the inner diameter of the end cover are fitted with a small clearance; the end cover is placed in the through hole of the upper compartment plate and connected by fasteners, and the outer diameter of the end cover and the through hole of the upper compartment plate are fitted with a clearance.

2. The spherical cylindrical storage tank assembly structure as described in claim 1, characterized in that, The end cap includes a first annular cylinder and a first flange. The first flange is disposed at one end of the first annular cylinder. The first flange is provided with a bushing mounting hole, an upper compartment plate mounting hole and a pin hole. The bushing mounting hole is used to connect the bushing, the upper compartment plate mounting hole is used to connect the upper compartment plate, and the pin hole is used to install a shear positioning pin. The upper compartment plate mounting hole is an oblong hole.

3. The spherical cylindrical storage tank assembly structure as described in claim 1, characterized in that, The bushing includes a second annular cylinder and a second flange. The second flange is disposed at one end of the second annular cylinder and has an end cap mounting hole for connecting an end cap.

4. The spherical cylindrical storage tank assembly structure as described in claim 1, characterized in that, A threaded through hole is opened at the top end of the spherical storage tank.

5. The assembly method of the spherical tank assembly structure according to any one of claims 1 to 4, characterized in that, include: A flat flange is added to the waist of the spherical tank. During assembly, the flat flange at the waist of the spherical tank is fixed to the lower compartment plate. The upper compartment is installed onto the transverse main structure of the spacecraft body, ensuring that the top end of the spherical tank is inserted into the through hole of the upper compartment during the process. The bushing is inserted into the end cap, the bushing and the end cap are bonded together with adhesive, and the bushing and the end cap are connected by a third fastener to obtain the end cap bushing assembly. Insert the end cap bushing assembly into the through hole of the upper compartment plate, and fit the top end of the spherical tank into the end cap bushing assembly. Use a second fastener to connect the end cap bushing assembly to the upper compartment plate. Based on the pin holes on the end cover bushing assembly, make pin holes on the upper compartment plate and then install shear positioning pins.

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