T-shaped vibration reduction ring structure of super-large C-shaped fuel tank for ship and assembly process of T-shaped vibration reduction ring structure

Abstract

The T-shaped vibration reduction ring structure is arranged on the inner wall of the fuel tank, a T-shaped vibration reduction ring comprises a vibration reduction ring web and a vibration reduction ring panel, the vibration reduction ring panel is parallel to the inner wall of the fuel tank, one end of the vibration reduction ring web and the middle of one side of the vibration reduction ring panel are aligned and vertically installed to form a T-shaped structure, and the other end of the vibration reduction ring web and the middle of one side of the vibration reduction ring panel are connected with the vibration reduction ring panel. The other end of the vibration reduction ring web plate is fixedly attached to the inner wall of the fuel tank through the fuel tank reinforcing ring, and the whole T-shaped vibration reduction ring is vertically installed in the fuel tank. The fuel tank has the advantages that on the basis that the original structure of the fuel tank is not changed, the T-shaped vibration reduction rings are stacked at the reinforcing rings of the fuel tank, so that the boundary rigidity of fuel tank supporting is improved, the vibration response level when the super-large C-shaped fuel tank is excited by a ship main engine and a propeller can be effectively reduced, and the fuel tank supporting effect is improved. And the structural reliability of the fuel tank and the operation safety of the ship are greatly improved.

Description

Technical Field

[0001] The invention relates to the technical field of IMO C-type fuel tank structures, and in particular to a T-shaped vibration damping ring structure and an assembly process of a super-large C-type fuel tank for a ship. Background Art

[0002] The C-type fuel tank for ships is arranged on the hull, close to vibration excitation sources such as the main engine and propeller. The impact of vibration factors on the safety of the tank structure cannot be ignored. At the same time, with the continuous increase in the demand for endurance, the size of the fuel tank has become larger, making the natural frequency value of the fuel tank lower, and it is impossible to completely avoid the excitation frequency range corresponding to the main engine speed range during ship operation.

[0003] If the natural frequency of the tank overlaps with the frequency of the excitation source, it may cause a large tank vibration response. According to research, when the fuel tank is arranged along the length of the ship, the upper rigidity of the tank support saddle is weak, and the lateral vibration response value of the tank in the ship width direction is usually large. The fuel tank is in a state of large vibration response for a long time, which is very likely to cause vibration fatigue damage, causing the tank structure to fail, and bringing uncontrollable risks to the safe operation of the ship. It is extremely important to design a vibration reduction structure with a simple structure that can significantly reduce the vibration response of the tank and a supporting assembly process. Summary of the invention

[0004] The purpose of the present invention is to provide a T-type vibration damping ring structure and an assembly process for a super-large C-type fuel tank for a ship, which can effectively reduce the vibration response level of the super-large C-type fuel tank when excited by a ship main engine and a propeller.

[0005] The above technical objectives of the present invention are achieved through the following technical solutions: A T-shaped vibration damping ring structure for an extra-large C-shaped marine fuel tank, characterized in that it is arranged on the inner wall of the fuel tank, the T-shaped vibration damping ring comprises a vibration damping ring web and a vibration damping ring panel, the vibration damping ring panel is parallel to the inner wall of the fuel tank, one end of the vibration damping ring web is aligned with the middle part of one side of the vibration damping ring panel and vertically installed to form a T-shaped structure, the other end of the vibration damping ring web is fixedly fitted to the inner wall of the fuel tank through a fuel tank reinforcement ring, and the T-shaped vibration damping ring is vertically installed as a whole in the fuel tank.

[0006] Preferably, the outer wall of the fuel tank is symmetrically provided with two groups of fuel tank support saddles, and the T-shaped vibration damping ring is provided with two groups, which are respectively installed on the inner wall of the fuel tank at the position of the fuel tank support saddles.

[0007] Preferably, the fuel tank reinforcement ring includes a fuel tank reinforcement ring web and a fuel tank reinforcement ring panel, the middle part of one side of the fuel tank reinforcement ring panel is vertically installed with the other end of the vibration damping ring web, one end of the fuel tank reinforcement ring web is vertically installed with the middle part of the other side of the fuel tank reinforcement ring panel, and the other end of the fuel tank reinforcement ring web is vertically installed with the inner wall of the fuel tank.

[0008] Preferably, the vibration damping ring web and the vibration damping ring face plate are connected by segmented splicing.

[0009] Preferably, the butt joint of the web of the vibration damping ring needs to be offset from the butt joint of the face plate of the vibration damping ring by at least 200 mm.

[0010] Preferably, the webs of the vibration damping ring are all arranged with equal depth, and the depth H of the webs of the vibration damping ring is 0.3m-0.5m; the panels of the vibration damping ring are arranged with equal width, and the width B of the panels of the vibration damping ring is 0.2m-0.4m.

[0011] Preferably, the material of the vibration damping ring web and the vibration damping ring face plate is consistent with the material of the fuel tank.

[0012] Preferably, the butt joints of the vibration damping ring panels are polished until the weld surfaces are smooth.

[0013] A T-type vibration damping ring structure assembly process for a super-large C-type fuel tank for a ship, characterized in that it comprises the following steps: (1) First, place the fuel tank reinforcement ring horizontally on a special welding frame, align the center line of the vibration damping ring web with the fuel tank reinforcement ring web, and fillet weld them to the reinforcement ring panel section by section. The remaining section of the vibration damping ring web is assembled in the final stage; (2) Then, the vibration damping ring face plate is fillet welded to one end of the vibration damping ring web in sections by T-shaped assembly, and the remaining section of the vibration damping ring face plate at the position of the vibration damping ring web that has not been assembled is also left for assembly in the final stage; (3) Then, the sections of the vibration damping ring panels assembled on the fuel tank reinforcement ring are butt-welded; (4) The web plates of the vibration damping rings assembled on the reinforcement rings of the fuel tanks are then butt-welded; (5) Then, fillet weld the remaining section of the vibration damping ring web to the fuel tank reinforcement ring panel by referring to the method in step (1); (6) Then fillet weld the remaining section of the vibration damping ring panel to the vibration damping ring web; (7) Complete the remaining butt weld on the upper surface side; (8) Finally, the fuel tank reinforcement ring and the vibration damping ring are turned over as a whole and placed horizontally on a special welding frame to complete the butt welding of the vibration damping ring web on the other side, the fillet welding between the vibration damping ring web and the fuel tank reinforcement ring panel, and the vibration damping ring web and the vibration damping ring panel.

[0014] In summary, the beneficial effects of the present invention are as follows: without changing the original structure of the fuel tank, by superimposing a T-shaped vibration damping ring at the reinforcement ring of the fuel tank, the lateral rigidity of the tank body at the saddle position is improved, thereby improving the boundary rigidity of the fuel tank support, effectively reducing the lateral vibration response of the fuel tank under external excitation, and reducing the risk of structural failure of the tank body due to vibration fatigue damage. The vibration damping ring structure is reasonably designed, simple in structure and low in cost. At the same time, the assembly process described in the present invention is adopted, which is convenient for installation and easy to manufacture. By reserving a section of the vibration damping ring web and panel until the final stage of assembly, the processing error and welding deformation are absorbed, thereby ensuring that the entire assembly process is high in precision, good in welding quality, and low in welding residual stress. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a side view structural schematic diagram of an ultra-large C-type fuel tank for a ship in the prior art; Figure 2 It is a cross-sectional schematic diagram of a T-shaped vibration damping ring structure of a super-large C-shaped fuel tank for a ship of the present invention; Figure 3 It is a cross-sectional schematic diagram of a T-shaped vibration damping ring structure of an extra-large C-shaped fuel tank for a ship of the present invention. DETAILED DESCRIPTION

[0016] The specific implementation manner of the present invention is further described below in conjunction with the accompanying drawings, and this embodiment does not constitute a limitation of the present invention.

[0017] like Figure 1 As shown, conventional prior art usually increases the number of vacuum rings in the fuel tank or increases the size of the vacuum rings in the fuel tank to reduce the vibration response of the tank body. The structure is relatively complex, not conducive to processing and manufacturing, and the material cost is relatively high.

[0018] like Figure 2 and Figure 3 The T-shaped vibration damping ring structure of a super-large C-shaped fuel tank for a ship is shown, which is arranged on the inner wall of the fuel tank 5. The T-shaped vibration damping ring includes a vibration damping ring web 1 and a vibration damping ring panel 2. The vibration damping ring panel 2 is parallel to the inner wall of the fuel tank 5. One end of the vibration damping ring web 1 is aligned with the middle part of one side of the vibration damping ring panel 2 and vertically installed to form a T-shaped structure. The other end of the vibration damping ring web 1 is fixedly fitted to the inner wall of the fuel tank 5 through a fuel tank reinforcement ring. The T-shaped vibration damping ring is vertically installed in the fuel tank 5 as a whole.

[0019] Two groups of fuel tank support saddles 6 are symmetrically arranged on the outer wall of the fuel tank 5 , and two groups of T-shaped vibration damping rings are arranged, which are respectively installed on the inner wall of the fuel tank 5 at the positions of the fuel tank support saddles 6 .

[0020] The fuel tank reinforcement ring includes a fuel tank reinforcement ring web 3 and a fuel tank reinforcement ring panel 4. The middle of one side of the fuel tank reinforcement ring panel 4 is vertically installed with the other end of the vibration damping ring web 1, one end of the fuel tank reinforcement ring web 3 is vertically installed with the middle of the other side of the fuel tank reinforcement ring panel 4, and the other end of the fuel tank reinforcement ring web 3 is vertically installed with the inner wall of the fuel tank 5.

[0021] The vibration damping ring web 1 and the vibration damping ring face plate 2 are connected by segmented splicing. The thickness of different segmented plates needs to be determined in combination with finite element strength analysis to meet the strength requirements of various calculation conditions specified in the specifications.

[0022] The butt joint of the vibration damping ring web 1 needs to be offset from the butt joint of the vibration damping ring face plate 2 by at least 200 mm to prevent the expansion of weld defects.

[0023] The vibration damping ring webs 1 are all set at equal depths. The depth H of the vibration damping ring webs 1 is 0.3 meters to 0.5 meters. The specific depth is determined according to the calculation requirements of the tank vibration response. The depth of the vibration damping ring webs 1 should not be too large to reduce the local structural vibration caused by the liquid sloshing load inside the tank.

[0024] The vibration-damping ring panels 2 are set to have equal widths. The width B of the vibration-damping ring panels 2 is 0.2 meters to 0.4 meters. The specific width is determined according to the tank vibration response calculation requirements. The width of the vibration-damping ring panels 2 should not be too large to avoid setting up additional panel anti-tilt structures.

[0025] The materials of the vibration damping ring web 1 and the vibration damping ring face plate 2 are consistent with the materials of the fuel tank 5. Since the temperature of the loaded LNG fuel is as low as -163°C, the low temperature performance of the vibration damping ring web 1 and the vibration damping ring face plate 2 must be considered.

[0026] The butt joints of the vibration-damping ring panels 2 are all polished until the weld surfaces are smooth, thereby alleviating stress concentration at the butt joints of the vibration-damping ring panels 2 .

[0027] An assembly process of a T-type vibration damping ring structure of a super-large C-type fuel tank for a ship comprises the following steps: (1) First, place the fuel tank reinforcement ring horizontally on a special welding frame, align the center lines of the vibration damping ring web 1 and the fuel tank reinforcement ring web 3, and fillet weld them to the fuel tank reinforcement ring panel 4 section by section, and the remaining section of the vibration damping ring web 1 is assembled in the final stage; (2) Then, the vibration damping ring face plate 2 is fillet welded to one end of the vibration damping ring web 1 in sections by using a T-shaped assembly method, and the remaining section of the vibration damping ring face plate 2 at the position of the vibration damping ring web 1 that has not been assembled is also left for assembly in the final stage; (3) Then, the sections of the vibration damping ring face plate 2 assembled to the reinforcement ring of the fuel tank are butt-welded; (4) The sections of the vibration damping ring web 1 assembled on the fuel tank reinforcement ring are then butt-welded; (5) The remaining section of the vibration damping ring web 1 is then fillet welded to the fuel tank reinforcement ring panel 4 by referring to the method in step (1); (6) Then, fillet weld the remaining section of the vibration damping ring face plate 2 to the vibration damping ring web 1; (7) Complete the remaining butt weld on the upper surface side; (8) Finally, the fuel tank reinforcement ring and the vibration damping ring are turned over as a whole and placed horizontally on a special welding frame to complete the butt welding of the vibration damping ring web 1 on the other side, the fillet welding between the vibration damping ring web 1 and the fuel tank reinforcement ring panel 4, and the vibration damping ring web 1 and the vibration damping ring panel 2.

[0028] The present invention increases the rigidity of the fuel tank reinforcement ring by superimposing a T-shaped vibration damping ring on the fuel tank reinforcement ring without changing the original structure of the fuel tank, thereby improving the boundary stiffness of the fuel tank support, effectively reducing the risk of excessive vibration response of the fuel tank, and ensuring the operational safety of the ship throughout its life cycle. Compared with the conventional method of increasing the number of fuel tank vacuum rings or increasing the size of the fuel tank vacuum ring to reduce the vibration response of the tank body, the present invention has a simple structure, is easy to process, has low material cost, and has no effect on the original structure of the fuel tank. At the same time, the assembly process described in the present invention is adopted to absorb processing errors and welding deformations by reserving a section of the vibration damping ring web and panel until the final stage of assembly, thereby ensuring assembly accuracy, reducing welding residual stress, and ensuring welding quality.

[0029] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art may make various modifications or equivalent substitutions to the present invention within the essence and protection scope of the present invention, and such modifications or equivalent substitutions should also be deemed to fall within the protection scope of the technical solution of the present invention.

Claims

1. A T-type vibration damping ring structure for a super-large C-type fuel tank for a ship, characterized in that: It is arranged on the inner wall of the fuel tank, and the T-shaped vibration damping ring includes a vibration damping ring web and a vibration damping ring panel. The vibration damping ring panel is parallel to the inner wall of the fuel tank, one end of the vibration damping ring web is aligned with the middle part of one side of the vibration damping ring panel and vertically installed to form a T-shaped structure, and the other end of the vibration damping ring web is fixed and fitted to the inner wall of the fuel tank through a fuel tank reinforcement ring, and the T-shaped vibration damping ring is vertically installed in the fuel tank as a whole.

2. The T-shaped vibration damping ring structure of a super-large C-shaped fuel tank for a ship according to claim 1 is characterized in that: The outer wall of the fuel tank is symmetrically provided with two groups of fuel tank support saddles, and the T-shaped vibration damping rings are provided with two groups, which are respectively installed on the inner wall of the fuel tank at the positions of the fuel tank support saddles.

3. The T-shaped vibration damping ring structure of a super-large C-shaped fuel tank for a ship according to claim 1 is characterized in that: The fuel tank reinforcement ring includes a fuel tank reinforcement ring web and a fuel tank reinforcement ring panel. The middle part of one side of the fuel tank reinforcement ring panel is vertically installed with the other end of the vibration damping ring web, one end of the fuel tank reinforcement ring web is vertically installed with the middle part of the other side of the fuel tank reinforcement ring panel, and the other end of the fuel tank reinforcement ring web is vertically installed with the inner wall of the fuel tank.

4. The T-shaped vibration damping ring structure of a super-large C-shaped fuel tank for a ship according to claim 1 is characterized in that: The vibration-damping ring web and the vibration-damping ring face plate are both connected by segmented splicing.

5. The T-type vibration damping ring structure of a super-large C-type fuel tank for a ship according to claim 4 is characterized in that: The butt joint of the web of the vibration damping ring needs to be offset from the butt joint of the face plate of the vibration damping ring by at least 200 mm.

6. The T-type vibration damping ring structure of a super-large C-type fuel tank for a ship according to claim 4 is characterized in that: The webs of the vibration damping rings are all arranged with equal depth, and the depth H of the webs of the vibration damping rings is 0.3m-0.5m. The panels of the vibration damping rings are arranged with equal width, and the width B of the panels of the vibration damping rings is 0.2m-0.4m.

7. The T-shaped vibration damping ring structure of a super-large C-shaped fuel tank for a ship according to claim 1 is characterized in that: The material of the vibration damping ring web and the vibration damping ring face plate is consistent with that of the fuel tank.

8. The T-shaped vibration damping ring structure of a super-large C-shaped fuel tank for a ship according to claim 1 is characterized in that: The butt joints of the vibration damping ring panels are polished until the weld surfaces are smooth.

9. A T-type vibration damping ring structure assembly process for a super-large C-type fuel tank for a ship, characterized in that: The steps include: (1) First, place the fuel tank reinforcement ring horizontally on a special welding frame, align the center line of the vibration damping ring web with the fuel tank reinforcement ring web, and fillet weld them to the reinforcement ring panel section by section. The remaining section of the vibration damping ring web is assembled in the final stage; (2) Then, the vibration damping ring face plate is fillet welded to one end of the vibration damping ring web in sections by T-shaped assembly, and the remaining section of the vibration damping ring face plate at the position of the vibration damping ring web that has not been assembled is also left for assembly in the final stage; (3) Then, the sections of the vibration damping ring panels assembled on the fuel tank reinforcement ring are butt-welded; (4) The web plates of the vibration damping rings assembled on the reinforcement rings of the fuel tanks are then butt-welded; (5) Then, fillet weld the remaining section of the vibration damping ring web to the fuel tank reinforcement ring panel by referring to the method in step (1); (6) Then fillet weld the remaining section of the vibration damping ring panel to the vibration damping ring web; (7) Complete the remaining butt weld on the upper surface side; (8) Finally, the fuel tank reinforcement ring and the vibration damping ring are turned over as a whole and placed horizontally on a special welding frame to complete the butt welding of the vibration damping ring web on the other side, the fillet welding between the vibration damping ring web and the fuel tank reinforcement ring panel, and the vibration damping ring web and the vibration damping ring panel.

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