Folding type swash bulkhead
By designing a foldable sway control bulkhead, the problems of heavy weight and numerous components in traditional sway control bulkhead structures were solved, achieving the effect of reducing structural weight and shipbuilding costs while ensuring strength and stability.
Patent Information
- Application Number
- CN202423133680.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-19
- Publication Date
- 2026-01-23
- Estimated Expiration
- 2034-12-19
AI Technical Summary
Traditional large oil tanker bulkhead structures have drawbacks such as small opening area, large number of components, heavy structural weight, and large amount of assembly and welding, making it difficult to optimize hull design to reduce empty ship weight and save shipbuilding costs while ensuring structural strength and stability.
The structure adopts a folded bulkhead, which consists of a folded section in the middle and straight sections at both ends. The cross-section of the folded section is a continuous triangle or semi-circle, and multiple light-reducing holes are opened on the web. It is connected to the longitudinal bulkhead and the inner bulkhead through the straight sections. The vertical stiffeners are eliminated, and large openings are designed to reduce the structural weight and facilitate construction and passage.
It achieves the reduction of the number of components and structural weight, the reduction of assembly and welding workload, the improvement of mechanization and construction convenience, and the reduction of plate weight and shipbuilding cost, while ensuring strength and stability.
Smart Images
Figure CN223821934U_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of marine vessel design and construction, and specifically relates to a foldable sway-damping bulkhead. Background Technology
[0002] In the field of ship design, sloshing-damping bulkheads are perforated bulkheads designed within liquid tanks. The purpose of this structure is to improve the stability and safety of ship navigation by reducing the influence of the free surface and minimizing the impact force generated by liquid sloshing on the watertight bulkhead. Especially under partially loaded cargo tank conditions (both empty and full), when the natural frequency of liquid sloshing approaches the ship's pitching frequency, the sloshing and pitching motions resonate, resulting in a significant impact on the cargo tank.
[0003] In large oil tankers, the liquid cargo tanks are relatively long. These longitudinally arranged tanks typically have sloshing-damping bulkheads to alter the sloshing frequency of the liquid within the tank and reduce damage to the bulkhead structure. Based on hydrodynamics and taking into full account the ship's motion characteristics and hull structure arrangement, various types of sloshing-damping bulkheads can be designed for ships.
[0004] Traditional large oil tanker bulkheads are constructed by welding vertical stiffeners to planar transverse bulkheads, forming a planar plate frame structure. To effectively prevent bulkhead buckling, horizontal buckling ribs are required to form a lattice structure. Several relief holes and drainage holes are drilled in the lattice to counteract the impact of liquid sloshing on the bulkhead.
[0005] Traditional hull designs suffer from drawbacks such as small opening areas, numerous structural components, heavy structural weight, and extensive assembly and welding. This patent aims to optimize the hull structure to improve ship performance and economy. While ensuring structural strength and stability, it reduces the number of components through improved hull design, thereby reducing the empty ship's weight and saving shipbuilding costs. Summary of the Invention
[0006] To solve the above problems, the present invention provides a foldable anti-sway bulkhead, the technical solution of which is as follows:
[0007] A foldable sway-damping bulkhead is used in a liquid cargo tank. The foldable sway-damping bulkhead consists of a folded section in the middle and straight sections at both ends. The cross-section of the folded section is a continuous triangle or semi-circle. Multiple relief holes are opened on the web of the folded section. The folding angle of the triangle is 60° to 120°.
[0008] The folding-type sway-controlling bulkhead connects to the longitudinal bulkhead and the inner bulkhead via straight sections. One end of the straight section aligns with the transverse strong frame double-hull side ribs, while the other end aligns with the vertical girder of the midship cargo hold. The top of the folding-type sway-controlling bulkhead connects to the horizontal girder, and the bottom connects to the inner bottom of the ship, or has a gap between them. This gap between the sway-controlling bulkhead and the inner bottom facilitates the drainage of residual oil and allows for the passage of larger mechanical equipment, increasing the mechanization of construction work within the bulkhead. Oil and water holes and door openings are located at the bottom of the folding section's web; the oil and water holes are either oval or elliptical.
[0009] Alternatively, there may be a gap between the bottom of the folded sway control bulkhead and the inner bottom of the ship. When there is a gap between the folded sway control bulkhead and the inner bottom of the ship, the bottom of the folded sway control bulkhead is a beveled structure with a bevel angle of 20° to 60°.
[0010] Furthermore, in the aforementioned folding type of sway control bulkhead, the width of the straight section is 600mm to 1000mm.
[0011] Furthermore, in the aforementioned type of folding sway control bulkhead, the width of the landing oval or landing elliptical hole does not exceed 70% of the width of the web at the triangular folding section.
[0012] Furthermore, the size of the holes in the aforementioned folding type of sway control bulkhead is reduced to 1200*600mm.
[0013] Furthermore, in the aforementioned folding type sway control bulkhead, a manhole is provided 600mm from the top horizontal girder on the folding section web.
[0014] Furthermore, the manhole size of the aforementioned folding type sway control bulkhead is 900*700mm.
[0015] Furthermore, the aforementioned folding type sway control bulkhead has a door opening with a height of 1900mm and a width of 900mm.
[0016] Furthermore, the aforementioned folding type sway control bulkhead reduces the vertical area of holes, door openings, and manholes by no more than 50%.
[0017] Furthermore, in the aforementioned folding type sway-damping bulkhead, an end soft toe is provided at the junction of the horizontal girders and the longitudinal bulkhead. The width of the end soft toe is not less than 500 mm and not more than 2000 mm, and the radius of the semicircle is 1000 mm.
[0018] The beneficial effects of this invention are:
[0019] 1. Compared to flat bulkheads, folding bulkheads do not employ vertical stiffeners. Their advantage lies in reducing the number of components, thus reducing structural weight and saving steel while maintaining the same strength.
[0020] 2. Compared with traditional planar bulkheads, this patent eliminates the stiffening material and its connecting elbow plate, and removes the horizontal truss B structure between the inner shell and the longitudinal bulkhead. This design can greatly reduce the number of components and structural weight, while also reducing the workload of assembly and welding.
[0021] 3. Foldable bulkheads have no vertical reinforcing ribs, which is more conducive to cleaning and rust prevention.
[0022] 4. Foldable bulkheads can be designed with larger manholes and larger oil and water holes, which is more conducive to personnel passage and reduces oil and water accumulation.
[0023] 5. The large opening design at the lower end of the folding bulkhead can significantly reduce the weight of the plates, facilitating construction and passage. Attached Figure Description
[0024] Figure 1 This is a front view schematic diagram of the connection between the folding type sway-damping bulkhead and the inner bottom of the ship;
[0025] Figure 2 yes Figure 1 Schematic diagram of side section structure;
[0026] Figure 3 This is a frontal structural diagram showing the gap between the folded sway control bulkhead and the ship's inner bottom;
[0027] Figure 4 yes Figure 3 Schematic diagram of side section structure;
[0028] Figure 5 This is a cross-sectional schematic diagram of a folded type bulkhead with triangular folding sections;
[0029] Figure 6 This is a cross-sectional schematic diagram of a folded type bulkhead with a semi-circular folding section.
[0030] Among them, 1-folded type sway-damping bulkhead, 2-straight section, 3-folded section, 4-lightening hole, 5-oil and water hole, 6-door hole, 7-manhole, 8-vertical girder, 9-horizontal girder, 10-double side rib, 11-inner bottom plate, 12-end soft toe, 13-inner shell, 14-longitudinal bulkhead, 15-large opening. Detailed Implementation
[0031] The invention will be further described with reference to the accompanying drawings.
[0032] A type of folding sway-damping bulkhead, such as Figure 1 , 2As shown, the liquid cargo tank uses a folding-type sway-damping bulkhead, which consists of a folded section in the middle and straight sections at both ends. The cross-section of the folded section is a continuous triangle or semi-circle, and multiple light-reducing holes are opened on the web of the folded section. The folding-type sway-damping bulkhead is connected to the longitudinal bulkhead and the inner wall of the tank through the straight sections. The straight section at one end of the folding-type sway-damping bulkhead is aligned with the transverse strong frame double-hull side ribs, and the straight section at the other end is aligned with the vertical girder of the middle cargo tank. The bottom of the folding-type sway-damping bulkhead is connected to the inner bottom of the ship, or there is a gap between it and the inner bottom of the ship.
[0033] The top of the folding type sway control bulkhead is connected to the horizontal girder, and the bottom is connected to the inner bottom of the ship. Oil and water holes and door holes are provided on the bottom web of the folding section. The oil and water holes are either oval holes or elliptical holes.
[0034] like Figure 5 As shown, the folded sway control bulkhead has a triangular cross-section. This type of bulkhead relies solely on the bending of the plates for sufficient strength support. The bending angle of the triangles is consistent, ranging from 60° to 120°, and the bending depth is between 0.5 and 2 times the rib spacing. Based on the actual width between the inner hull and the longitudinal bulkhead, as well as the bending angle and depth, the bulkhead plates are folded into multiple angles. Depending on the actual factory processing capabilities and plate width, each plate can withstand 1-3 folds. Therefore, the entire bulkhead plate needs to be divided into multiple plates for bending before welding. Due to strength calculations, the bulkhead plates have different thicknesses in the vertical direction, and in necessary cases, transverse seams are required to divide the plate into upper and lower sections.
[0035] The triangular folding section of the folded sway control bulkhead has a bending depth of 1100mm and a bending angle of 104°. The actual width between the inner shell and the longitudinal bulkhead is 15280mm. The sway control bulkhead plate is folded into 11 folds, with a total of 1 transverse plate seam and 5 vertical plate seams, dividing the bulkhead into 11 plates.
[0036] A doorway is located near the first bend of the longitudinal bulkhead. This doorway is a floor-mounted, square opening measuring 1800*900 mm, with semi-circular transitions at the four corners. Oil and water holes are located at the bottom of the remaining straight sections. Three to five oval-shaped lightening holes, each measuring 1200*600 mm, are installed along the height. A 900*700 mm manhole is located 600 mm downwards from the horizontal girder for easy access during construction. Considering the thickness requirements of the upper and lower plates, the structure is divided into two sections along the height. In actual fabrication, the transverse plate joints are first joined, and after the upper and lower plates are joined, the entire structure is bent.
[0037] like Figure 3 , 4As shown, a large opening can be created between the lower end of the folded sway control bulkhead and its inner bottom, raising the bottom to a height between 1500mm and 3500mm (the height of the large opening). From this height, the folded bulkhead can be beveled at an angle between 20° and 60°. This large opening design can also be applied to sway control bulkheads with a semi-circular folded section, and its design principle is the same as that of triangular sway control bulkheads.
[0038] like Figure 6 As shown, the folded bulkhead has a semi-circular cross-section. This semi-circular bulkhead is formed by roll forming and welding. The roll forming radius is determined by the actual width between the inner hull and the longitudinal bulkhead, as well as the roll forming depth. The roll forming depth is between 0.5 and 2 times the rib spacing, and the flat plate is rolled into multiple semi-circles or minor arcs. Depending on the actual factory processing capacity and plate width, each plate can only withstand 1-3 roll forming cycles. Therefore, the entire bulkhead plate needs to be divided into multiple plates for roll forming before welding.
[0039] The semi-circular bulkhead has an actual width of 15280mm between the inner shell and the longitudinal bulkhead, a rolling depth of 1100mm, a rolling radius of 980mm, and is equipped with one transverse plate seam and four vertical plate seams. The bulkhead is divided into nine plates with a total of nine bends.
Claims
1. A folding type anti-sway bulkhead, characterized in that, The folding type of sway control bulkhead consists of a folded section in the middle and straight sections at both ends. The cross-section of the folded section is a continuous triangle or semi-circle. Multiple light-reducing holes are opened on the web of the folded section. The folding angle of the triangle is 60° to 120°. The folding sway-controlling bulkhead is connected to the longitudinal bulkhead and the inner bulkhead through a straight section. The straight section at one end of the folding sway-controlling bulkhead is aligned with the transverse strong frame double-hull side ribs, and the straight section at the other end is aligned with the vertical girder of the mid-cargo hold. The top of the folding sway-controlling bulkhead is connected to the horizontal girder, and the bottom of the folding sway-controlling bulkhead is connected to the inner bottom of the ship. Oil and water holes and door holes are provided at the bottom of the folding section web. The oil and water holes are floor-mounted oval holes or floor-mounted elliptical holes.
2. A folding type anti-sway bulkhead according to claim 1, characterized in that, The width of the straight section is 600mm to 1000mm.
3. A folding type anti-sway bulkhead according to claim 1, characterized in that, The width of the oval or elliptical hole should not exceed 70% of the width of the web at the triangular folded section.
4. A folding type anti-sway bulkhead according to claim 1, characterized in that, The size of the lightening hole is 1200*600mm.
5. A folding type anti-sway bulkhead according to claim 1, characterized in that, A manhole is provided 600mm from the top horizontal truss on the web of the folded section.
6. A folding type anti-sway bulkhead according to claim 5, characterized in that, The manhole measures 900*700mm.
7. A folding type anti-sway bulkhead according to claim 1, characterized in that, The door opening is 1900mm high and 900mm wide.
8. A folding type anti-sway bulkhead according to claim 5, characterized in that, The reduction area of the hole, door hole, and manhole in the vertical direction shall not exceed 50%.
9. A folding type anti-sway bulkhead according to claim 1, characterized in that, A soft toe is provided at the junction of the horizontal girder and the longitudinal bulkhead. The width of the soft toe is not less than 500 mm and not more than 2000 mm, and the radius of the semicircle is 1000 mm.