Low-cost integrally-formed boosting storage box structure without transition ring

Abstract

A low-cost integrally-formed boosting storage box structure without a transition ring comprises a box bottom, a short shell and a barrel section. The box bottom and the short shell are connected in a spot welding mode after being sleeved to form a box bottom assembly; and the box bottom assembly and the cylinder section butt joint circumferential weld are connected by adopting a fusion welding process. Transition ring structures among the short shell, the box bottom and the barrel section of the storage box are omitted, the straight line section of the large end of the box bottom and the short shell are subjected to spot welding to form the box bottom assembly, and then the box bottom assembly and the barrel section are subjected to fusion welding, so that the expensive transition ring structures are saved, and three circumferential welding seams for connecting the transition ring with the box bottom, the barrel section and the short shell are simplified into a circle of spot welding area and a fusion welding circumferential welding seam; and low-cost rapid manufacturing is realized. According to the box bottom adopting the integral spinning process, the scalloped segment metal plate machining procedure is reduced, and the production pressure of the scalloped segment forming process is relieved; longitudinal seams and circular seams are avoided. The problems that the connecting cost of the transition ring is high, the production period of the tailor-welded box bottom is long, and the production efficiency of the short cylinder section is low are solved.

Description

Technical Field

[0001] The invention relates to a low-cost integrally formed booster tank structure without a transition ring, belonging to the technical field of aerospace vehicle propellant tank structures. Background Art

[0002] The propellant tank is a key component of the launch vehicle's power system and structural system. It plays the role of transmitting force, maintaining shape, storing and transporting propellants, etc. It accounts for about 50-60% of the weight of the rocket body structure, and has high requirements for lightness and reliability. The tank structure is usually composed of a front short shell, a front bottom, a barrel section, a rear bottom, and a rear short shell. The short shell, the bottom and the barrel section of a conventional tank need to be connected by a transition ring. The connection forms include a docking transition ring and a locking bottom transition ring. See Figure 1 As shown in the figure, the transition ring is generally made of aluminum alloy forging ring.

[0003] The bottom of a conventional tank is composed of a top cover and several melon slices, which are formed by stamping or stretching the parts first and then welding them together. In the case of equal thickness, the strength of the weld is lower than that of the metal parent material. From the perspective of quality assurance, the weld needs to be inspected by X-ray, and the longitudinal seams of the melon slices need to be inspected for hydraulic pressure and airtightness one by one.

[0004] The length of each section of the conventional tank is different. Each section is welded together from two wall panels, with a circular anti-sway frame and a tensioning angle piece spot welded in the middle. Figure 2 As shown, the large number of shell segments leads to a large number of longitudinal seams and annular seams in the tank, and low production efficiency.

[0005] In summary, there are still some problems with the current conventional tank structure, mainly including the following points:

[0006] (1) The short shell, bottom and cylinder section of the tank are connected by transition rings, which are made of aluminum alloy forging rings, which are expensive and have a long production cycle.

[0007] (2) The bottom of the box is composed of a top cover + several melon slices welded together. The welds need to be inspected by X-ray, and each longitudinal seam needs to be inspected for hydraulic pressure and air tightness. This requires many processes and a long cycle.

[0008] (3) Each shell section of the cylinder section is short and the number is large, the number of longitudinal seams and circumferential seams of the tank is large, and the production efficiency is low. Summary of the invention

[0009] The technical problem solved by the present invention is: to overcome the shortcomings of the prior art, to provide a low-cost integrally formed booster tank structure without a transition ring, to solve the problems of high cost of transition ring connection, long production cycle of welded tank bottom, low production efficiency of short barrel section, etc., to achieve the purpose of reducing the number of main welds of the booster tank, shortening the hydraulic and airtight test cycle, shortening the production cycle of the entire tank, etc.

[0010] The technical solution of the present invention is:

[0011] A low-cost integrally formed booster tank structure without a transition ring, comprising: a tank bottom, a short shell, and a barrel section;

[0012] After the box bottom and the short shell are assembled, they are connected by resistance spot welding to form a box bottom assembly; the butt ring weld between the box bottom assembly and the barrel section is connected by fusion welding.

[0013] Furthermore, the bottom of the box is processed by an integral spinning process without longitudinal seams and circumferential seams.

[0014] Furthermore, the bottom of the box is an ellipsoidal bottom in the shape of an inverted bowl, and a straight tube section is extended at the edge of the large end for spot welding connection with the short shell.

[0015] Furthermore, there is a thickness change in the middle area of ​​the box bottom to adapt to the difference in bearing capacity of different second curvature radii at different positions of the ellipsoidal bottom box bottom.

[0016] Furthermore, the box bottom and the short shell are connected by resistance spot welding after being assembled, and the spot welding area is specifically as follows:

[0017] The resistance spot welding area is located at the straight section extending from the edge of the large end of the box bottom. The outside of the straight section is a short shell. When welding, spot welding is performed from the outside to the inside, that is, spot welding from the short shell to the bottom of the box, and the short shell is welded through.

[0018] Furthermore, the welding points of the resistance spot welding are divided into three layers: upper, middle and lower. The welding points of each layer are located on a circumference. The welding points on each circumference are evenly distributed, and the adjacent welding points are 30 mm apart; the welding points of adjacent layers are staggered; the spacing between layers is 20 to 30 mm.

[0019] Furthermore, the box bottom assembly and the cylinder section are connected by a fusion welding process through a butt ring weld. Specifically, the straight cylinder section extended at the edge of the large end of the box bottom has the same diameter as the cylinder section and is connected to the cylinder section by fusion welding. The fusion welding ring weld is the butt ring weld.

[0020] Furthermore, there is no transition ring connection structure between the box bottom assembly and the barrel section.

[0021] Furthermore, the barrel section adopts a standard length barrel section of 1918 mm.

[0022] Furthermore, in order to adapt to tanks of different lengths, a modular barrel segment combination method of N standard length barrel segments and 1 free length barrel segment is adopted.

[0023] The beneficial effects of the present invention compared with the prior art are:

[0024] (1) The transition ring structure between the short shell, the tank bottom and the cylinder section of the storage tank of the present invention is eliminated. The straight section at the large end of the tank bottom is spot welded to the short shell to form a tank bottom assembly, which is then fusion welded to the cylinder section, thereby saving the expensive transition ring structure. The three circumferential welds connecting the transition ring with the tank bottom, the cylinder section and the short shell are simplified to a circle of spot welding areas and a fusion welding circumferential weld, thereby achieving low-cost and rapid manufacturing.

[0025] (2) The present invention adopts an integral spinning process for the box bottom, which reduces the number of melon slice sheet metal processing steps and alleviates the production pressure of the melon slice forming process; there are no longitudinal seams and circumferential seams, eliminating the welding process of the single bottom weld and the hydraulic and airtight inspection processes, shortening the product production and inspection cycle and improving product reliability; the profile of the integrally spun box bottom is closer to the theoretical profile than the profile of the melon slice welded box bottom, which helps to maintain the consistency of the box volume; at the same time, based on the original bottom profile, a straight line segment is extended at the large end of the box bottom to achieve spot welding with the short shell.

[0026] (3) When the width of the raw materials permits, the present invention takes into account the maximum utilization rate of the width of the plate and the total length of the conventional booster tank, adopts a tank barrel section with a standard length of 1918 mm, increases the length of the shell section, reduces the tank barrel section of the conventional booster tank by one section, reduces the number of longitudinal seams by two and the number of circumferential seams by one, reduces the number of shell section welding times and the number of weld inspections, and improves production efficiency; takes the 1918 mm long barrel section as the standard length shell section, forms a modular barrel section design method of N standard length barrel sections + 1 free length barrel section, which can be applied to other types of tanks of different lengths. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 Schematic diagram of existing tank transition ring (left: docking transition ring, right: bottom locking transition ring);

[0028] Figure 2 It is a schematic diagram of a traditional short tube section;

[0029] Figure 3 This is a structural diagram of the low-cost integrally formed booster tank without a transition ring according to the present invention;

[0030] Figure 4 It is a cross-sectional axonometric view of the connection between the short shell and the barrel section of the bottom of the box without a transition ring according to the present invention;

[0031] Figure 5 It is a cross-sectional view of the connection between the short shell and the barrel section of the bottom of the box without a transition ring according to the present invention;

[0032] Figure 6 This is a schematic diagram of the integral spinning box bottom structure of the present invention;

[0033] Figure 7 This is a schematic diagram of the structure of a standard length long tube section described in the present invention. DETAILED DESCRIPTION

[0034] The specific embodiments of the present invention are further described in detail below with reference to the accompanying drawings.

[0035] like Figure 3 , Figure 4 As shown, the present invention proposes a low-cost integrally formed booster tank structure without a transition ring, comprising: a tank bottom 1, a short shell 2, and a barrel section 3;

[0036] After the box bottom 1 and the short shell 2 are assembled, they are connected by resistance spot welding to form a box bottom assembly; the butt ring weld between the box bottom assembly and the barrel section 3 is connected by fusion welding.

[0037] like Figure 6 As shown, the box bottom 1 is processed by an integral spinning process, replacing the original box bottom welded with a top cover and a plurality of melon slices, and eliminating the longitudinal seam and the annular seam;

[0038] The box bottom 1 is an ellipsoid bottom in the shape of an inverted bowl, and a straight tube section is extended at the edge of the large end for spot welding connection with the short shell 2.

[0039] Furthermore, there is a thickness change in the middle area of ​​the box bottom 1 to adapt to the difference in bearing capacity of different second curvature radii at different positions of the ellipsoidal bottom box bottom.

[0040] Furthermore, the box bottom 1 and the short shell 2 are connected by resistance spot welding after being assembled, and the spot welding area is specifically:

[0041] The resistance spot welding area is located at the straight section extending from the edge of the large end of the box bottom 1. The outside of the straight section is the short shell 2. When welding, spot welding is performed from the outside to the inside, that is, spot welding from the short shell 2 to the box bottom 1, and the short shell 2 is welded through.

[0042] Resistance spot welding welding point Figure 5 As shown in the elliptical mark, the resistance spot welding welds are divided into three layers: upper, middle and lower. The welds in each layer are located on a circle. The welds on each circle are evenly distributed, and the adjacent welds are 30 mm apart. The welds in adjacent layers are staggered; the spacing between layers is 20 to 30 mm.

[0043] Fusion welding butt girth weld Figure 5 As shown in the triangle mark, the butt ring weld between the bottom assembly and the barrel section 3 is connected by fusion welding, eliminating the traditional transition ring connection structure. Specifically, the straight barrel section extended at the edge of the large end of the bottom 1 has the same diameter as the barrel section 3 and is connected to the barrel section 3 by fusion welding. The fusion welding ring weld is the butt ring weld.

[0044] Furthermore, there is no transition ring connection structure between the box bottom assembly and the barrel section 3.

[0045] like Figure 7 As shown in the attached Figure 7As shown, the barrel section adopts the standard length barrel section of 1918mm obtained by comprehensively considering the requirements of different models, which can meet the factory's anti-sway plate spot welding requirements and barrel section welding requirements, and does not affect the installation of all accessories in the tank. The barrel section of the relevant model booster tank can be combined in a modular way of standard length productized barrel section + other lengths. That is, in order to adapt to tanks of different lengths, a modular barrel section combination of N standard length barrel sections and 1 free length barrel section is adopted.

[0046] The transition ring structure between the short shell, the tank bottom and the cylinder section of the storage tank of the present invention is eliminated, and the straight section at the large end of the tank bottom is spot welded to the short shell to form a tank bottom assembly, which is then fusion welded to the cylinder section, thereby saving the expensive transition ring structure, and simplifying the three circumferential welds connecting the transition ring with the tank bottom, the cylinder section and the short shell respectively into a circle of spot welding areas and a fusion welding circumferential weld, thereby realizing low-cost and rapid manufacturing.

[0047] Parts of the present invention that are not described in detail belong to common knowledge among those skilled in the art.

Claims

1. A low-cost integrally formed booster tank structure without transition ring, Features include: Box bottom (1), short shell (2), cylinder section (3); After the box bottom (1) and the short shell (2) are assembled, they are connected by resistance spot welding to form a box bottom assembly; the butt ring weld between the box bottom assembly and the barrel section (3) is connected by fusion welding.

2. A low-cost integrally formed booster tank structure without a transition ring according to claim 1, Features: The box bottom (1) is processed by an integral spinning process and has no longitudinal seams or annular seams.

3. A low-cost integrally formed booster tank structure without a transition ring according to claim 1, Features: The box bottom (1) is an ellipsoid bottom in the shape of an inverted bowl, and a straight tube section is extended at the edge of the large end for spot welding connection with the short shell (2).

4. A low-cost integrally formed booster tank structure without a transition ring according to claim 1, Features: The middle area of ​​the box bottom (1) has a thickness change to adapt to the difference in bearing capacity of different second curvature radii at different positions of the ellipsoidal box bottom.

5. A low-cost integrally formed booster tank structure without a transition ring according to claim 3, Features: After the box bottom (1) and the short shell (2) are assembled, they are connected by resistance spot welding. The spot welding area is specifically: The resistance spot welding area is located at a straight section extending from the edge of the large end of the box bottom (1), and the outer side of the straight section is a short shell (2) mounted thereon. When welding, spot welding is performed from the outside to the inside, that is, spot welding is performed from the short shell (2) toward the box bottom (1), and the short shell (2) is welded through.

6. A low-cost integrally formed booster tank structure without a transition ring according to claim 5, Features: The welding points of resistance spot welding are divided into three layers: upper, middle and lower. The welding points of each layer are located on a circle. The welding points on each circle are evenly distributed, and the adjacent welding points are 30mm apart. The welding points of adjacent layers are staggered; the spacing between layers is 20 to 30mm.

7. A low-cost integrally formed booster tank structure without a transition ring according to claim 3, Features: The box bottom assembly and the cylinder section (3) are connected by a fusion welding process through a butt ring weld. Specifically, the straight cylinder section extended at the large end edge of the box bottom (1) has the same diameter as the cylinder section (3) and is connected to the cylinder section (3) by fusion welding. The fusion welding ring weld is the butt ring weld.

8. A low-cost integrally formed booster tank structure without a transition ring according to claim 1, Features: There is no transition ring connection structure between the box bottom assembly and the barrel section (3).

9. A low-cost integrally formed booster tank structure without a transition ring according to claim 1, Features: The barrel section (3) adopts a standard length barrel section of 1918 mm.

10. A low-cost integrally formed booster tank structure without a transition ring according to claim 9, Features: In order to adapt to tanks of different lengths, a modular barrel segment combination method of N standard length barrel segments and 1 free length barrel segment is adopted.

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