Bending type oscillation stopping wall structure of marine large C-shaped fuel tank
By employing a bent anti-sway wall structure in a large C-type fuel tank, increasing the section modulus and improving welding processes, the problem of resonance in the anti-sway wall was solved, the stiffness and natural frequency of the anti-sway wall were improved, the vibration response was reduced, and the safety of the fuel tank and the operational safety of the ship were ensured.
Patent Information
- Application Number
- CN202520461146.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-17
- Publication Date
- 2025-12-23
- Estimated Expiration
- 2035-03-17
AI Technical Summary
The anti-sloshing walls of large C-type fuel tanks are prone to resonance during ship operation, especially near the main engine and propeller, which leads to a decrease in vibration frequency and affects the safety of the fuel tank.
A bent anti-sloshing wall structure for a large marine C-type fuel tank is designed. The anti-sloshing wall structure is connected by ring ribs of the tank body. Bent panels and T-shaped profiles are used to increase the section modulus and improve the stiffness. Through continuous welding, the bent anti-sloshing wall structure is formed, which increases its section modulus and thus increases the natural frequency of the anti-sloshing wall itself, thereby reducing the vibration response.
It effectively improves the stiffness and natural frequency of the anti-sloshing wall, reduces vibration response, lowers the risk of fuel tank damage due to vibration fatigue, ensures the safety of ship operation, and is simple and low in cost to manufacture.
Smart Images
Figure CN223709312U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the technical field of large marine C-type fuel tanks, and in particular to a bent anti-sway wall structure for a large marine C-type fuel tank. Background Technology
[0002] With the implementation of environmental conventions and regional emission restrictions, the shipbuilding industry is vigorously researching various methods and technologies to reduce emissions, and natural gas fuel is gradually becoming a new choice for ship owners and ship designers. Currently, Type C LNG fuel storage tanks are the preferred choice for bulk carriers and oil tankers due to their simple construction and assembly and fewer related patent barriers.
[0003] As an effective structure for reducing liquid sloshing within fuel tanks, anti-sloshing wall structures are widely used. With the increasing demands for ship range leading to larger fuel tank sizes, the size of anti-sloshing walls is also increasing. This results in a decrease in the natural frequency of the ribbed anti-sloshing wall, making it impossible to completely avoid the excitation frequency range corresponding to the main engine speed during ship operation, thus increasing the risk of resonance. Especially when fuel tanks are located close to vibration excitation sources such as the main engine and propeller, the impact of vibration factors on fuel tank safety becomes even more significant. Therefore, designing a large anti-sloshing wall structure that is simple in construction, easy to manufacture, and can significantly increase its natural frequency and reduce its vibration response is extremely important. Utility Model Content
[0004] The purpose of this invention is to provide a bent anti-sloshing wall structure for a large marine C-type fuel tank, which reduces the sloshing of liquid inside the fuel tank while increasing its natural frequency and reducing the vibration response level of the anti-sloshing wall itself when excited by the main engine and propeller.
[0005] The above-mentioned technical objective of this utility model is achieved through the following technical solution:
[0006] A bent anti-sway wall structure for a large marine C-type fuel tank includes a tank body ring rib and an anti-sway wall. The tank body ring rib is connected to the fuel tank shell, and the anti-sway wall structure is connected inside the tank body ring rib. The anti-sway wall structure includes bent panels and T-shaped profiles arranged at intervals. Several holes are opened on the bent panels. The projections of the bent panels and T-shaped profiles on the horizontal plane are both symmetrical zigzag shapes, and their bending angles are the same as their bending positions.
[0007] Furthermore, the cross-section of the tank body ring rib is T-shaped, including a ring rib web and a ring rib panel. The ring rib web is connected to the inner peripheral wall of the fuel tank shell, and the ring rib panel is connected to the inner periphery of the ring rib web. Both ends of the bent panel and the T-shaped profile are connected to the inner periphery of the ring rib panel.
[0008] Furthermore, the holes on the bent panel are arranged symmetrically.
[0009] Furthermore, the bent panel and T-profile include a first connecting segment, a second connecting segment, a third connecting segment and a fourth connecting segment, wherein the first connecting segment and the fourth connecting segment are symmetrically arranged, and the second connecting segment and the third connecting segment are symmetrically arranged.
[0010] Furthermore, the first connecting segment and the fourth connecting segment are located on a straight line.
[0011] Furthermore, the second connecting segment and the third connecting segment are set at an obtuse angle.
[0012] Furthermore, the included angle between the first connecting segment and the second connecting segment is 135°~150°.
[0013] Furthermore, the maximum distance from each point on the T-profile to the line connecting its two endpoints is 0.2 meters to 0.4 meters.
[0014] Furthermore, the bent panel is welded to the inner side of the tank body's ring ribs.
[0015] In summary, this utility model has the following beneficial effects:
[0016] 1. The anti-sloshing wall is welded to the tank body at all four sides and is subject to strong constraints; the center of the anti-sloshing wall is far from the tank body and is subject to weaker constraints. Under the impact of liquid sloshing, the deformation of the anti-sloshing wall increases from the periphery to the center. Similarly, under the excitation of the ship's main engine and propeller, the vibration amplitude of the anti-sloshing wall increases from the periphery to the center.
[0017] Therefore, in this application, the section modulus of the sway barrier can be effectively increased by bending the panel of the sway barrier, and increasing the section modulus can significantly improve the stiffness of the sway barrier itself; improving the stiffness of the sway barrier itself can effectively increase the natural frequency of the sway barrier and reduce the vibration response.
[0018] Compared to corrugated plates, channel plates, and other structural types, bent panels have a stronger ability to suppress vibration. For large tanks that require a significant increase in the stiffness of the anti-vibration wall itself, the bent panel structural type mentioned in this invention is more suitable.
[0019] 2. Furthermore, structural types such as corrugated plates and channel plates require processing such as stamping. The large size of the sway barrier leads to a significant decrease in its rigidity. If corrugated plates or channel plates are used, the plate thickness needs to be increased considerably, making manufacturing more difficult.
[0020] In this application, the structure of the bent panel can be completed by continuous welding, which is extremely convenient to manufacture. At the same time, the C-type fuel tank is loaded with liquefied fuel at -163°C. The tank body has obvious cold shrinkage along the axial direction. Therefore, the welding path between the sway wall and the tank body should be kept within a cross-section as much as possible to reduce the contact between the sway wall and the tank body and reduce the impact of the inconsistent cold shrinkage rate between the tank body and the sway wall.
[0021] 3. In summary, this application, while meeting the structural strength requirements of the fuel tank and achieving the function of reducing liquid sloshing, improves the rigidity of the anti-sloshing wall itself by stacking T-shaped profiles on bent panels. This effectively reduces the vibration response level of the large C-type fuel tank anti-sloshing wall structure under the excitation of the ship's main engine and propeller, reducing the risk of structural failure caused by vibration fatigue damage to the tank. The invention is reasonably designed, easy to assemble, low in cost, and safe to use. It effectively reduces the risk caused by excessive vibration response of the fuel tank anti-sloshing wall, thereby ensuring the operational safety of the ship throughout its entire life cycle and greatly improving the structural reliability of the fuel tank and the operational safety of the ship. Attached Figure Description
[0022] Figure 1 This is a schematic diagram of the installation position of the bent anti-sway wall structure of a large marine C-type fuel tank according to the present invention.
[0023] Figure 2 This is a schematic diagram of a bent anti-sway wall structure for a large marine C-type fuel tank according to this utility model.
[0024] Figure 3 This is a front view of the bent anti-sway wall structure of a large marine C-type fuel tank according to this utility model.
[0025] Figure 4 This is a top view of the T-section of a bent sway barrier structure for a large marine C-type fuel tank.
[0026] In the diagram, 1 is the bent panel; 2 is the T-profile; 3 is the hole; 4 is the ring-ribbed web; 5 is the ring-ribbed panel; 6 is the fuel tank shell; 7 is the first connecting section; 8 is the second connecting section; 9 is the third connecting section; and 10 is the fourth connecting section. Detailed Implementation
[0027] The specific embodiments of this utility model will be further described below with reference to the accompanying drawings. These embodiments do not constitute a limitation on this utility model. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this application.
[0028] A bent anti-sloshing wall structure for a large marine C-type fuel tank, such as Figure 1 and Figure 2 As shown, it includes a tank ring rib, which is connected to the middle cross-section of the fuel tank shell 6. The anti-sway wall structure is welded in the tank ring rib by continuous welding. In this embodiment, the anti-sway wall structure is located at the tank ring rib in the middle of the fuel tank shell 6, which effectively reduces the vibration response level of the large C-type fuel tank anti-sway wall structure itself under the excitation of the ship's main engine and propeller, and improves the structural reliability of the fuel tank and the safety of ship operation.
[0029] Specifically, the anti-sway wall structure includes a bent panel 1 and a T-shaped profile 2 arranged at intervals. The cross-section of the tank ring rib is T-shaped, which includes a ring rib web 4 and a ring rib panel 5. The ring rib web 4 is connected to the inner peripheral wall of the fuel tank shell 6, and the ring rib panel 5 is connected to the inner periphery of the ring rib web 4. The bent panel 1 and the T-shaped profile 2 are welded together, and both ends are connected to the inner periphery of the ring rib panel 5.
[0030] like Figure 3 As shown, the bent panel 1 and the T-shaped profile 2 are welded together to form a complete bent anti-sway wall structure; and several holes 3 are opened on the bent panel 1. The holes 3 on the bent panel 1 are symmetrically arranged, and they can also be opened in other regular arrangements; in this embodiment, a whole large horizontal groove is opened on the uppermost and lowermost bent panels 1, and circular holes 3 are symmetrically arranged on the remaining bent panels 1.
[0031] like Figure 4 As shown, the projections of the bent panel 1 and the T-profile 2 on the horizontal plane are both symmetrical polygonal shapes, and their bending angles and bending positions are the same. They are both continuously welded to the tank ring rib panel 5. The bending angle of the bent panel 1 and the density of the holes 3 can be adjusted according to the vibration response requirements of the tank's anti-sloshing wall. The structural materials of the bent panel 1 and the T-profile 2 are consistent with the fuel tank material, and their plate thickness dimensions at each position can be determined by combining finite element strength analysis and other methods to meet the strength requirements of each calculation condition specified in the standard, while effectively reducing the vibration response level. The protrusion orientation of the T-profile 2 and the bent panel 1 can be determined according to the convenience of equipment layout, manufacturing, and maintenance inside the fuel tank.
[0032] like Figure 4 As shown, in this embodiment, the bent panel 1 and the T-profile 2 include a first connecting segment 7, a second connecting segment 8, a third connecting segment 9, and a fourth connecting segment 10, which are welded together and have bending dividing lines. The first connecting segment 7 and the fourth connecting segment 10 are symmetrically arranged, as are the second connecting segment 8 and the third connecting segment 9. The first connecting segment 7 and the fourth connecting segment 10 are located on a straight line. The second connecting segment 8 and the third connecting segment 9 are arranged at an obtuse angle.
[0033] The angle between the first connecting section 7 and the second connecting section 8 is 135°~150°; the specific bending angle can also be determined according to the tank vibration response calculation requirements. By determining the excitation frequency range of the ship's main engine and propeller, the natural frequency of the planar anti-sway wall can be calculated; as the bending angle of the anti-sway wall panel increases, the natural frequency of the anti-sway wall also increases, so that the natural frequency is outside the excitation frequency range of the main engine and propeller; the bending angle of its panel should not be too large, so as to reduce the stress concentration problem at the bending point of the anti-sway wall itself.
[0034] like Figure 4 As shown, the depth of T-profile 2, i.e., the maximum distance from each point on it to the line connecting the two endpoints (the distance between the midpoint of T-profile 2 and the first connecting section 7), is 0.2 meters to 0.4 meters. The specific depth can also be determined according to the tank vibration response calculation requirements. The natural frequency of the anti-sloshing wall increases with the increase of the web depth of T-profile 2, so that the natural frequency is outside the excitation frequency range of the main engine and propeller. The web depth of T-profile 2 should not be too large to reduce the local structural vibration caused by the liquid sloshing load inside the tank. The bending angle of the panel and the web depth of T-profile 2 can be matched to achieve a better combination to avoid excitation.
[0035] The production process includes,
[0036] a) The bent panel 1 and T-profile 2 are cut into four parts: the first connecting section 7, the second connecting section 8, the third connecting section 9 and the fourth connecting section 10 respectively;
[0037] b) A set of bent panels 1 corresponds to a set of T-profiles 2 (the middle part can be set to two sets of bent panels 1 corresponding to a set of T-profiles 2). Their connecting sections are continuously welded to the upper and lower parts to obtain four components. Then the ends of the components (bent panels 1 and T-profiles 2) can be beveled to facilitate subsequent welding.
[0038] c) First, align the components corresponding to the first connecting section 7 and the fourth connecting section 10 with the center line and weld them to the tank ring rib by continuous welding to ensure that the T-profiles 2 of both are horizontal and coplanar with the ring rib web plate 4.
[0039] d) According to the preset bending angle, the components corresponding to the second connecting segment 8 and the third connecting segment 9 are welded to the first connecting segment 7 and the fourth connecting segment 10 respectively by continuous welding. Finally, the components corresponding to the second connecting segment 8 and the third connecting segment 9 are welded into one piece by continuous welding.
[0040] Repeat the above steps to complete the welding and fixing between the bent panel 1, T-profile 2 and the tank ring rib. During the welding process in steps c) and d), the corresponding components can also be welded and fixed to each other with the components welded in the previous cycle, and finally the installation of the anti-sway wall structure is completed.
[0041] Among them, the dimensions of the T-profile 2 at the bend need to be calculated accurately so that the bend can be spliced smoothly and each T-profile 2 can be welded together into a whole; the welds between the bent panels 1, between the bent panels 1 and the ring rib panels 5, and between the bent panels 1 and the T-profile 2 can be improved by grinding the welds to enhance the fatigue life of the structure.
[0042] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model. Those skilled in the art can make various modifications or equivalent substitutions to the present utility model within its substance and protection scope, and such modifications or equivalent substitutions should also be considered to fall within the protection scope of the present utility model's technical solution.
Claims
1. A bent anti-sway wall structure for a large marine C-type fuel tank, characterized in that: It includes a tank ring rib, which is connected to the fuel tank shell. The tank ring rib is connected to a sway-stopping wall structure. The sway-stopping wall structure includes bent panels and T-shaped profiles arranged at intervals. Several holes are opened on the bent panels. The projections of the bent panels and T-shaped profiles on the horizontal plane are symmetrical polygonal shapes, and their bending angles and bending positions are the same.
2. The bent anti-sway wall structure of a large marine C-type fuel tank according to claim 1, characterized in that: The cross-section of the tank ring rib is T-shaped, including a ring rib web and a ring rib panel. The ring rib web is connected to the inner circumferential wall of the fuel tank shell, and the ring rib panel is connected to the inner circumference of the ring rib web. Both ends of the bent panel and the T-shaped profile are connected to the inner circumference of the ring rib panel.
3. The bent anti-sway wall structure of a large marine C-type fuel tank according to claim 1 or 2, characterized in that: The holes on the bent panel are arranged symmetrically.
4. The bent anti-sway wall structure of a large marine C-type fuel tank according to claim 1, characterized in that: The bent panel and T-profile include a first connecting segment, a second connecting segment, a third connecting segment and a fourth connecting segment, wherein the first connecting segment and the fourth connecting segment are symmetrically arranged, and the second connecting segment and the third connecting segment are symmetrically arranged.
5. The bent anti-sway wall structure of a large marine C-type fuel tank according to claim 4, characterized in that: The first connecting segment and the fourth connecting segment are located on a straight line.
6. The bent anti-sway wall structure of a large marine C-type fuel tank according to claim 4 or 5, characterized in that: The second connecting segment and the third connecting segment are set at an obtuse angle.
7. The bent anti-sway wall structure of a large marine C-type fuel tank according to claim 4 or 5, characterized in that: The angle between the first connecting segment and the second connecting segment is 135°~150°.
8. The bent anti-sway wall structure of a large marine C-type fuel tank according to claim 1 or 4, characterized in that: The maximum distance from each point on the T-profile to the line connecting its two endpoints is 0.2 meters to 0.4 meters.
9. The bent anti-sway wall structure of a large marine C-type fuel tank according to claim 1 or 2, characterized in that: The bent panel is welded to the inner side of the tank's ring ribs.