Split combined module buttress structure of deepwater FPSO (Floating Production Storage and Offloading)

Abstract

The invention relates to a deepwater floating production storage and offloading (FPSO) split combined module buttress structure, which belongs to the technical field of ocean engineering design and manufacture, and comprises a module buttress base and a module buttress interface, the module buttress interface is arranged on the module buttress base, a soft toe structure is arranged at the end part of the module buttress base, and the module buttress base is arranged in a crossed manner or in a shape like a Chinese character'feng '. Through the split combined design, the integration difficulty is reduced, errors in the integration process can be effectively avoided, the strength fatigue characteristic is improved, and the construction difficulty is reduced. According to the invention, a reinforcing structure under the deck is reduced, and an alignment structure is reduced. The floating production storage and offloading (FPSO) module buttress integrated structure is high in deck utilization efficiency, low in construction difficulty, low in integration difficulty and high in reliability.

Description

Technical Field

[0001] The invention relates to a FPSO split combined module buttress structure, in particular to a FPSO module buttress design under severe sea conditions, and belongs to the technical field of marine engineering design and manufacturing. Background Art

[0002] Floating production storage and offloading system (FPSO) is a modular and highly integrated high-end offshore engineering equipment that integrates oil and gas production, storage and export. The FPSO module pier is one of the most critical positions in the FPSO design and is crucial to the long-term stable operation of the FPSO.

[0003] The actual practices of module piers at home and abroad are also different, but the design idea is to minimize the participation of module piers in the total longitudinal strength and reduce the impact of the hull beam on the module. The different forms of module piers mainly depend on the environmental conditions of the sea area where the FPSO is used and the size of the module's own load.

[0004] The published patent "A FLNG upper module pier system" (CN 106122766A) designs the module pier as a closed box-type structure. The pier structure proposed in the patent is a closed structure, which has insufficient construction space and is difficult to weld. In particular, the full penetration welds of the sealing plate often cannot be cleaned from the back, and the fatigue resistance is poor, making integration difficult.

[0005] The published patent "A deepwater FPSO open module pier structure" (CN 117465620A) designs the module pier as an open pier form. The pier structure proposed in the patent is an open structure. The open structure is a monomer structure, which requires high precision in the process. In particular, a module usually has 6 piers. It is very difficult to require the module piers to be completely consistent with the modules, resulting in high difficulty in integrating such piers.

[0006] In the actual construction process, it is very difficult to fully fit the six module piers with the bottom surfaces of the six module legs. Even if there is no problem with the initial design or construction, new errors will still appear during the construction, transportation, and lifting process. These errors often need to be solved by hard pulling during the integration process. Conventional pier designs do not have the ability to make secondary adjustments. Forcing the interface to align will cause the structure to produce a large initial stress, which is very unfavorable for the long-term operation of the ship. At the same time, previous designs often have stress concentration at the interface of the main deck. Once fatigue cracks appear, cracks will extend to the main deck, causing oil and gas leakage, causing huge economic losses. The reliability and maintainability of its design and construction require extreme attention. Even if stress concentration is controlled, there will still be a large design risk. Summary of the invention

[0007] The object of the present invention is to overcome the defects of the prior art and obtain a module pier structure that is convenient for installation and integration, can easily adjust the installation error, ensure the use of the module, has a simple construction process, and is safe and reliable.

[0008] To achieve the above object, the technical solution of the present invention provides a deep-water FPSO split combined module pier structure, including a module pier base and a module pier interface. The module pier interface is arranged on the module pier base. A soft toe structure is provided at the end of the module pier base, and the module pier base is arranged in a cross-shaped or rich-character cross arrangement.

[0009] Preferably, the module pier interface is provided with a module pier top plate, a longitudinal cross plate, a transverse cross plate, a skirt plate, and an anti-tilting elbow plate. The module pier base is provided with a base top plate, a base transverse plate, and a base longitudinal plate.

[0010] Preferably, each component is connected into an integral body by full penetration welding. The base is integrally formed with the segment, and the connection between the module pier interface and the module pier base is welded after the module is hoisted.

[0011] Preferably, the skirt plate support is added around the module pier top plate. The skirt plate is welded to the module pier base by fillet welding, and connection elbow plates are added as required.

[0012] Preferably, the anti-tilting elbow plate is added under the module pier top plate. The anti-tilting elbow plate is in the form of a plain plate or a stiffened plate.

[0013] Preferably, the heights of the module pier base and the module pier interface are different. The height of the module pier base is 0.5 - 3 m, and the height of the module pier interface is 0.5 - 3 m.

[0014] Preferably, different plate thickness combinations can be adopted for each component within the plate thickness range.

[0015] Preferably, the thickness of the cross plate is 12 - 60 mm.

[0016] Preferably, the length of the soft toe structure is 60 - 200 mm.

[0017] Preferably, the connection between the module pier top plate and the module bottom plate can adopt bolt and rubber connection.

[0018] In summary, the present invention includes the following beneficial technical effects:

[0019] Through the split combined form, the present invention patent maximally avoids the defects in the construction process, improves the strength fatigue characteristics, and reduces the construction difficulty.

[0020] The split combined piers reduce the impact of module and hull construction errors on integration difficulty. The patent of this invention reduces the integration difficulty of the hull and the upper mold. When errors occur, they can be adjusted through welds or interface structures, increasing the reliability of the piers and connection structures.

[0021] The patent of this invention increases the available area of ​​the FPSO deck surface, reduces the difficulty of pier maintenance, and once fatigue cracks appear, the cracks are located above the base and maintenance can still be carried out at sea without causing production stoppage, with little impact on the operating losses of the FPSO.

[0022] The patent of the present invention is a FPSO module pier split combination structure with high deck utilization efficiency, low integration difficulty, ability to compensate for construction errors, small losses even if problems occur, offshore maintenance, and high reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a longitudinal section view of a module buttress in a deepwater FPSO split combined module buttress structure of the present invention;

[0024] Figure 2 A top view of a module buttress interface in a deepwater FPSO split combined module buttress structure of the present invention;

[0025] Figure 3 A top view of a module buttress base in a deepwater FPSO split combined module buttress structure according to the present invention;

[0026] Figure 4 It is a cross-sectional view of a module buttress in a deepwater FPSO split combined module buttress structure of the present invention;

[0027] Figure 5 It is a top view of another form of module buttress interface in a deepwater FPSO split combined module buttress structure of the present invention;

[0028] Figure 6 The present invention is a top view of another type of module buttress base in a deepwater FPSO split combined module buttress structure.

[0029] Figure numerals: 1. Module pier interface; 1-1. Module pier top plate; 1-2. Cross plate longitudinal; 1-3. Cross plate transverse; 1-4. Skirt plate; 1-5. Anti-tilt toggle plate; 2. Module pier base; 2-1. Base top plate; 2-2. Base transverse plate; 2-3. Base longitudinal plate. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0032] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments, but is not intended to be a limitation of the present invention.

[0033] The embodiment of the present invention provides a deepwater FPSO split modular pier structure, wherein the modular pier is generally composed of two parts: a modular pier base 2 and a modular pier interface 1. The modular pier base 2 is arranged in a cross or a "F" shape, including a base top plate 2-1, a soft toe structure connected to the deck, and a base web. The modular pier interface 1 includes an interface plate, a coaming, a support plate, and the like.

[0034] In the above-mentioned modular pier, the end of the modular pier base 2 adopts a soft toe structure.

[0035] The module pier base 2 of the above-mentioned module pier is constructed together with the segment during segment construction to ensure good welding alignment accuracy. The module pier base 2 can also be constructed separately;

[0036] The above-mentioned module pier, the module pier base 2 and the module pier interface 1 are connected by welding.

[0037] The module buttress and the module buttress interface 1 are not welded to the module buttress interface 1 in the initial stage.

[0038] The module pier interface 1 of the module pier mentioned above is welded to the module pier base 2 after the module is hoisted.

[0039] In the above-mentioned module pier, the panel of the module pier interface 1 is welded to the panel of the module pier base 2, and the weld is polished and smooth after welding.

[0040] The above-mentioned module buttress, module buttress interface 1, and skirt plate 1-4 are welded to the module buttress top plate 1-1, and can also be directly beveled.

[0041] In the above-mentioned modular buttress, the connection between the modular buttress interface 1 and the modular buttress base 2 can be enhanced in anti-fatigue property by adding a soft toe bracket.

[0042] The module piers mentioned above generally have a height of not less than 650mm.

[0043] In the above-mentioned modular buttress, the angle between the skirt plate 1-4 of the modular buttress interface 1 and the modular buttress top plate 1-1 is generally between 90 and 150 degrees.

[0044] For the above-mentioned module piers with wider width, the module pier rigidity is increased by adding anti-tilt brackets 1-5 at wider positions to maintain the stability of the module pier.

[0045] The above-mentioned modular piers are usually divided into two types: fixed modular piers and sliding modular piers.

[0046] The above-mentioned module pier, the fixed module pier top plate 1-1 and the FPSO module bottom plate can also be connected by bolts, and rubber filling can be used between the fixed module pier top plate 1-1 and the FPSO module bottom plate to reduce the impact of hull deformation on the module. At the same time, the rubber between the fixed module pier top plate 1-1 and the FPSO module bottom plate can be replaced according to actual conditions.

[0047] The above-mentioned modular piers, the pier components and the connections between the piers and the main deck all adopt full penetration welding.

[0048] The key welds of the module piers mentioned above are C-shaped ground to increase the overall fatigue resistance of the piers.

[0049] The above-mentioned modular piers can optimize the local plate thickness configuration through an optimization algorithm to ensure that the pier strength and fatigue are well matched.

[0050] The module pier base 2 structure is built together with the segment to ensure the alignment accuracy. The module pier interface 1 structure is adjusted after the module is hoisted and then welded to the base.

[0051] The patent of the present invention reduces the difficulty of integration through a split modular design, can effectively avoid errors in the integration process, improve strength fatigue characteristics, and reduce construction difficulty. The present invention reduces the under-deck reinforcement structure and the alignment structure. The patent of the present invention is an FPSO module pier integrated structure with high deck utilization efficiency, low construction difficulty, low integration difficulty, and high reliability.

[0052] See also Figures 1 to 4 As shown, a FPSO split-assembly module pier structure is shown, which generally includes a module pier interface 1 and a module pier base 2.

[0053] The module pier interface 1 includes a module pier top plate 1-1, a cross plate longitudinal plate 1-2, a cross plate transverse plate 1-3, a skirt plate 1-4, and an anti-tilt bracket 1-5.

[0054] The module pier base 2 includes a base top plate 2-1, a base transverse plate 2-2, and a base longitudinal plate 2-3.

[0055] Specifically, the FPSO module is connected to the module pier top plate 1-1 through the FPSO module bottom plate, and the loads such as vertical force, horizontal force, bending moment, torque, etc. are transmitted to the hull structure. The FPSO module bottom plate and the module pier top plate 1-1 can be connected by welding, or by bolts + rubber pads, and the specific connection form can be changed according to the actual ship needs.

[0056] Furthermore, the module pier interface 1 can be welded into a whole according to design requirements.

[0057] Furthermore, the module pier base 2 can be welded integrally with the segments.

[0058] Furthermore, the height of the module pier interface 1 is 0.5 to 3 m, and the height of the component 2 is 0.25 to 1.5 m.

[0059] Furthermore, the top plate of the module pier interface 1 is 35-120 mm, and the top plate of the module pier interface 2 is 20-60 mm.

[0060] Furthermore, the thickness of the cross plate of the module buttress interface 1 and the module buttress base 2 is 12 to 60 mm.

[0061] Furthermore, the soft toe length of the module buttress base 2 is 60 to 200 mm.

[0062] Furthermore, the module pier interface 1 and the module pier base 2 are first fixed by spot welding or clamping, and after the module is hoisted, the weld between the module pier interface 1 and the module pier base 2 is welded.

[0063] Furthermore, if the module pier top plate 1-1 is too large, an anti-tilt bracket 1-5 may be provided to increase the rigidity of the top plate.

[0064] Furthermore, the connection between the module pier interface 1 and the module pier base 2 adopts the form of a soft toe bracket, and at the same time, the dangerous point is placed between the module pier interface 1 and the module pier base 2, which is easy to inspect and repair, thereby increasing the safety of the entire ship.

[0065] In a preferred embodiment of the present invention, the angle between the skirt plates 1-4 and the top plate can be adjusted as needed, and the size of the skirt plates 1-4 can also be adjusted; the height of the module pier interface 1 and the module pier base 2 and their relative heights can be adjusted according to the actual position of the ship equipment to meet the strength requirements, which is particularly suitable as a module pier for FPSO / FLNG, etc., to reduce the operating costs of ship owners and improve operating efficiency.

[0066] The above description is only a preferred embodiment of the present invention, and does not limit the implementation method and protection scope of the present invention. For those skilled in the art, it should be aware that all solutions obtained by equivalent substitutions and obvious changes made using the present invention's patent description and illustrations should be included in the protection scope of the present invention. Figure 5 and Figure 6 Another preferred embodiment of member 1 and member 2 is given.

Claims

1. A deepwater FPSO split modular pier structure, characterized in that: The invention comprises a module buttress base (2) and a module buttress interface (1), wherein the module buttress interface (1) is arranged on the module buttress base (2), a soft toe structure is arranged at the end of the module buttress base (2), and the module buttress base (2) is arranged in a cross shape or a "F" shape.

2. A deepwater FPSO split modular pier structure according to claim 1, characterized in that: The module buttress interface (1) is provided with a module buttress top plate (1-1), a cross plate longitudinal plate (1-2), a cross plate transverse plate (1-3), a skirt plate (1-4), and an anti-tilt toggle plate (1-5); the module buttress base (2) is provided with a base top plate (2-1), a base transverse plate (2-2), and a base longitudinal plate (2-3).

3. A deepwater FPSO split modular pier structure according to claim 2, characterized in that: The components are connected into one piece by full penetration welding, the base and the segments are integrally formed, and the connection between the module pier interface (1) and the module pier base (2) is welded after the module is hoisted.

4. A deepwater FPSO split modular pier structure according to claim 2, characterized in that: The skirt plate (1-4) is added around the module buttress top plate (1-1) for support, the skirt plate (1-4) and the module buttress base (2) are welded by fillet welding, and a connecting bracket is added as needed.

5. The deepwater FPSO split modular pier structure according to claim 2, characterized in that: The anti-tilt bracket (1-5) is added under the module buttress top plate (1-1), and the anti-tilt bracket (1-5) is in the form of a plain plate or a reinforced plate.

6. The deepwater FPSO split modular pier structure according to claim 2, characterized in that: The module buttress base (2) and the module buttress interface (1) have different heights: the module buttress base (2) has a height of 0.25 to 1.5 m, and the module buttress interface (1) has a height of 0.5 to 3 m.

7. The deepwater FPSO split modular pier structure according to claim 2, characterized in that: Different plate thickness combinations can be used for components within the plate thickness range.

8. The deepwater FPSO split modular pier structure according to claim 2, characterized in that: The thickness of the cross plate is 12 to 60 mm.

9. The deepwater FPSO split modular pier structure according to claim 2, characterized in that: The length of the soft toe structure is 60 to 200 mm.

10. The deepwater FPSO split modular pier structure according to claim 2, characterized in that: The module buttress top plate (1-1) and the module bottom plate can be connected by bolts and rubber.

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