Offshore steel structure hoisting method with loading and hoisting functions

Abstract

The present application relates to the offshore steel structure hoisting technical field, specifically to an offshore steel structure hoisting method with loading and hoisting functions. S1: drive the crawler crane to the preset position of the deck of the large ship and fix; S2: navigate the large ship carrying the crawler crane to the target hoisting point of the steel structure; S3: use the crawler crane to hoist and transport the steel structure components on the transport ship to the temporary storage area; S4: the transport ship returns to the port empty to replenish, and the crawler crane accurately hoists the steel structure components in the loading area to the preset installation point on the sea; S5: repeat the operation procedures of S3 to S4 after the transport ship is fully loaded with components and docks again. The offshore steel structure hoisting operation can be completed without relying on a special offshore hoisting ship, the continuity of the hoisting operation is ensured, the multi-ship high-frequency collaborative docking operation scene is reduced, the construction management difficulty brought by the offshore multi-ship collaborative operation is reduced, and the hoisting construction demand of the offshore photovoltaic large-scale and continuous operation is adapted.

Description

Technical Field

[0001] This invention relates to the field of offshore steel structure hoisting technology, specifically a method for offshore steel structure hoisting that combines loading and lifting functions. Background Technology

[0002] With the continuous upgrading of the clean energy industry, offshore photovoltaic (PV) power, with its advantages of requiring less land, having good power generation stability, and being compatible with the energy layout of coastal areas, is gradually becoming an important development direction for marine new energy. Offshore PV projects are mostly deployed in open or near-shore areas, where the hydrological and meteorological conditions are complex. Environmental factors such as wind, waves, tides, and ocean currents have a significant impact on on-site construction organization, the stability of hoisting operations, and the management of construction windows. Steel structural components, as the core load-bearing structure of offshore PV power stations, encompass various types including support modules, trestle structures, and equipment platforms. The diverse specifications of these components and the dispersed hoisting points place high demands on the continuity, safety, and economy of offshore hoisting construction.

[0003] Currently, the installation of steel structures for offshore photovoltaic projects generally adopts a separate construction model, with transport vessels and dedicated crane vessels working together. This model separates component transfer and offshore hoisting operations into independent steps. However, this model has several shortcomings in practical application. Transport vessels need to repeatedly travel between ports and construction areas, while crane vessels remain idle during the transport vessels' return resupply periods, resulting in low utilization of ship and equipment and making it difficult to meet the demands of large-scale, continuous offshore construction. Furthermore, dedicated offshore crane vessels are scarce, with high leasing and maintenance costs. They are also susceptible to external constraints such as maritime control and vessel scheduling, increasing project investment and organizational complexity. In addition, the connection between component transfer and offshore hoisting relies on multi-vessel coordination. Fluctuations in sea conditions can easily cause delays in berthing and hoisting procedures, resulting in poor operational continuity. The routine multi-vessel coordination also increases safety management pressure during offshore construction, hindering the efficient, low-cost, and safe construction of offshore photovoltaic projects. Summary of the Invention

[0004] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a method for lifting and hoisting offshore steel structures that can adapt to the needs of large-scale and continuous offshore construction.

[0005] The technical solution adopted by this invention to solve its technical problem is:

[0006] A method for lifting and hoisting offshore steel structures, combining loading and lifting functions, involves pre-configuring a large vessel and a crawler crane. The specific steps are as follows:

[0007] S1: Complete the installation and commissioning of the crawler crane at the land terminal, drive the crawler crane to the preset position on the deck of the large ship and fix it, delineate the loading area on the deck of the large ship that is suitable for the working range of the crawler crane, and set up limiting fixtures in the loading area.

[0008] S2: The large ship equipped with a crawler crane will be sailed to the target lifting point of the steel structure, and the hull will be positioned and fixed by the anchoring system equipped on the large ship.

[0009] S3: The transport ship carrying steel structure components is moored to a large vessel, and the steel structure components on the transport ship are lifted by a crawler crane to the loading area for temporary storage. The steel structure components are then protected by limiting fixtures.

[0010] S4: The transport ship returns to the port empty to replenish its cargo. During the round trip of the transport ship, the crawler crane accurately lifts the steel structure components in the loading area to the preset installation points at sea.

[0011] S5: After the transport ship is fully loaded with components and berths again, the operation process from S3 to S4 is repeated to form a continuous cycle of hoisting operation mode until all steel structure components are hoisted.

[0012] The present invention, which adopts the above technical solution, has the following prominent features compared with the prior art:

[0013] This invention utilizes a large vessel equipped with a crawler crane to form an integrated operation platform. A dedicated loading area is set up on the vessel deck to temporarily buffer components. Continuous offshore lifting operations are carried out during the downtime between port replenishment by transport ships. This changes the traditional operation mode where transfer and lifting are completely separated. It effectively improves the problems of idle crane equipment and low utilization rate of ship machinery in traditional construction, reduces the dependence of construction progress on the rhythm of transport ship round trips, and eliminates the need for dedicated offshore crane vessels to complete offshore steel structure lifting operations. This reduces the reliance on special vessel resources and project investment in offshore construction. Simultaneously, by buffering components in advance to store construction materials, the impact of sea state fluctuations and vessel berthing delays on construction procedures is mitigated, ensuring the continuity of lifting operations. It also reduces the need for high-frequency coordinated berthing operations by multiple vessels, lowers the difficulty of construction management caused by multi-vessel operations at sea, and adapts to the large-scale, continuous lifting construction needs of offshore photovoltaic projects.

[0014] As a preferred embodiment, a further technical solution of the present invention is:

[0015] Preferably, an upper connecting seat is welded to the load-bearing hub of the crawler crane, and a connecting screw is installed inside the upper connecting seat. Multiple positioning seats are welded to the deck of a large ship, and a lower connecting seat connected to the corresponding positioning seat is provided at the bottom end of the connecting screw. By welding and fixing the upper connecting seat to the load-bearing hub of the crawler crane, assembling the connecting screw inside the upper connecting seat, welding and arranging multiple positioning seats on the deck of a large ship, and assembling the lower connecting seat corresponding to the corresponding positioning seat at the bottom end of the connecting screw, a reliable whole-machine assembly and fixing structure can be formed. This structure can adapt to the hull swaying and load transfer in the marine operating environment, improve the overall stability of the crawler crane during ship deck operations, reduce the possibility of equipment displacement during lifting operations, and adapt to dynamic marine operating conditions.

[0016] Preferably, the loading area is arranged along the slewing radius of the crawler crane, making full use of the crane's effective working range, rationally planning the component stacking area, facilitating the retrieval and hoisting of components nearby, optimizing the on-site construction layout, reducing blind spots in the hoisting process, and adapting to the needs of temporary storage and continuous hoisting operations for large quantities of steel structure components.

[0017] Preferably, the anchoring system in S2 adopts a multi-point anchoring layout, which can constrain the position of the hull from multiple directions, buffer the displacement and swaying interference of the hull caused by waves and currents in the sea area, improve the berthing stability of the operating vessel in complex sea conditions, and provide a stable operating platform foundation for high-precision and continuous lifting operations at sea.

[0018] Preferably, in S4, the large vessel is equipped with a vessel attitude monitoring system. When the crawler crane is lifting, it works in conjunction with the vessel attitude monitoring system to achieve precise alignment and installation of components through luffing and slewing adjustments. It can sense changes in the vessel's attitude in real time. With the dynamic adjustment of the crawler crane's luffing and slewing, it can adapt the lifting and alignment operation to the real-time state of the vessel, compensate for alignment deviations caused by slight fluctuations in the vessel's attitude, improve the accuracy of lifting and alignment of offshore steel structure components, and optimize the quality of lifting construction under complex sea conditions. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the main view of a large ship according to an embodiment of the present invention;

[0020] Figure 2 This is a top view structural diagram of a large ship according to an embodiment of the present invention;

[0021] Figure 3 This is a schematic diagram of the structure of the crawler crane fixedly connected to the deck according to an embodiment of the present invention;

[0022] Figure 4 This is a magnified front view of the crawler crane and its fixed connection to the deck according to an embodiment of the present invention.

[0023] Explanation of reference numerals in the attached drawings: 1. Large vessel; 2. Tracked crane; 3. Loading area; 4. Upper connecting seat; 5. Positioning seat; 6. Connecting screw; 7. Lower connecting seat. Detailed Implementation

[0024] The present invention will be further illustrated below with reference to specific embodiments. The purpose of this illustration is solely to provide a better understanding of the invention. Therefore, the examples given do not limit the scope of protection of the present invention.

[0025] like Figures 1 to 4 As shown in the figure, this embodiment presents a method for lifting offshore steel structures that combines loading and hoisting functions. A large vessel 1 and a crawler crane 2 are pre-configured. The crawler crane 2 is selected based on the maximum self-weight of the offshore photovoltaic steel structure components, the hoisting radius, and the offshore overturning load conditions, ensuring it meets the structural strength and stability requirements for heavy-load offshore hoisting operations. The large vessel 1 is a self-propelled deck cargo ship with a flat, wide deck, capable of ocean navigation and fixed-point berthing at sea. It is not a dedicated crane vessel but serves only as an offshore load-bearing platform. The hull possesses the structural rigidity, wave resistance, and overall stability required for offshore operations, making it suitable for both near-shore and offshore conventional offshore photovoltaic systems. The operational environment of the construction sea area is such that the large vessel used in this embodiment is a general-purpose large deck vessel for offshore photovoltaic construction. The conventional hull length is not less than 100m and the beam is not less than 15m. It has a large, flat, open-air working deck with no superstructure obstruction. The vessel's deadweight tonnage is not less than 3000 tons, and its draft is moderate. The hull stability meets the requirements for long-term fixed-point berthing and lifting load bearing at sea. The deck working area can completely cover the space requirements for the placement and rotation of the crawler crane, as well as the partitioned buffering and stacking of multiple batches of steel structural components. The hull structural strength can withstand the combined forces of the crawler crane's own weight, alternating lifting loads, and floating conditions at sea. The specific steps are as follows:

[0026] S1: Complete the installation and commissioning of crawler crane 2 at the land dock. The land dock is flat and hardened and meets the load-bearing conditions for the assembly, movement and commissioning of crawler crane 2. Complete the no-load and load commissioning of the whole machine's mechanical performance, slewing function, and lifting performance. Move crawler crane 2 to the preset position on the deck of large ship 1 and fix it. On the deck of large ship 1, delineate a loading area 3 that is suitable for the working range of crawler crane 2. The outline of loading area 3 is precisely matched with the effective working fan-shaped area of ​​the crane. Set up limiting fixtures in loading area 3.

[0027] S2: The large vessel 1, equipped with a crawler crane 2, is sailed to the target lifting point of the steel structure. During the sailing process, a safe and suitable working window is selected based on the real-time wind conditions, tidal rhythm and wave height conditions of the sea area. The hull is positioned and fixed by the anchoring system equipped on the large vessel 1.

[0028] S3: Before construction, the sea conditions parameters of the sea area are monitored in real time. After the sea conditions meet the safety requirements of the offshore hoisting construction, the transport ship carrying the steel structure components is moored to the large vessel 1. The approach speed and distance between the two ships are strictly controlled to keep the hulls in a stable and close state and avoid the risk of hard contact collision. The steel structure components on the transport ship are hoisted to the loading area 3 for temporary storage using the crawler crane 2. The steel structure components are limited and protected by the limiting fixture.

[0029] S4: The transport ship returns to the port empty to replenish its cargo. During the round trip of the transport ship, the crawler crane 2 accurately lifts the steel structure components in the loading area 3 to the preset installation point at sea.

[0030] S5: After the transport ship is fully loaded with components and berths again, the operation process from S3 to S4 is repeated to form a continuous cycle of hoisting operation mode until all steel structure components are hoisted.

[0031] Preferably, an upper connecting seat 4 is welded to the load-bearing hub of the crawler crane 2, and a connecting screw 6 is provided inside the upper connecting seat 4. Multiple positioning seats 5 are welded to the deck of the large ship 1. The bottom end of the connecting screw 6 is provided with a lower connecting seat 7 connected to the corresponding positioning seat 5. The upper connecting seat 4 is fixed by welding to the load-bearing hub of the crawler crane 2, the connecting screw 6 is assembled inside the upper connecting seat 4, multiple positioning seats 5 are welded and arranged on the deck of the large ship 1, and the bottom end of the connecting screw 6 is equipped with a lower connecting seat 7 corresponding to the corresponding positioning seat 5. The top of the connecting screw 6 passes through the upper connecting seat 4 and the end is provided with a locking nut. The positioning seat 5 is a bottom fixed on the deck of the large ship 1. The bottom plate has connecting ears, the lower connecting seat 7 is U-shaped with the opening facing downwards, the two side plates of the lower connecting seat 7 are right trapezoids with the hypotenuse facing upwards, the top of the lower connecting seat 7 is fixed to the connecting screw 6, and a pin is passed through the connecting ears and the side plates. Multiple sets of connecting structures of the lower connecting seat 7 are symmetrically and evenly arranged on both sides of the traveling base of the crawler crane 2 to form an integral tie-and-restraint system, which can form a reliable whole machine assembly and fixing structure, which can adapt to the hull sway and load transfer in the marine operation environment, improve the overall stability of the crawler crane 2 in the process of working on the deck of a large ship 1, reduce the possibility of equipment displacement during the lifting operation, and adapt to the dynamic working conditions at sea.

[0032] Preferably, the loading area 3 is arranged along the slewing radius of the crawler crane 2, making full use of the crane's effective working range, rationally planning the component stacking area, dividing the component into independent stacking zones according to the component specifications, size, and weight, facilitating the nearby retrieval and hoisting of components, optimizing the on-site construction layout, reducing blind spots in the hoisting process, and adapting to the needs of temporary storage and continuous hoisting operations for large quantities of steel structure components.

[0033] Preferably, the anchoring system in S2 adopts a multi-point anchoring layout, which can constrain the position of the hull from multiple directions, buffer the displacement and swaying interference of the hull caused by waves and currents in the sea area, improve the berthing stability of large ships 1 in complex sea conditions, and provide a stable operating platform for high-precision and continuous lifting operations at sea.

[0034] Preferably, in S4, the large vessel 1 is equipped with a vessel attitude monitoring system. When the crawler crane 2 is lifting, it works in conjunction with the vessel attitude monitoring system to achieve precise alignment and installation of components through amplitude and slewing adjustments. It can sense changes in the vessel's attitude in real time. With the dynamic adjustment of amplitude and slewing of the crawler crane 2, it can adapt the lifting and alignment operation to the real-time status of the large vessel 1, compensate for alignment deviations caused by slight fluctuations in the vessel's attitude, improve the accuracy of lifting and alignment of offshore steel structure components, and optimize the quality of lifting construction under complex sea conditions.

[0035] This invention utilizes a large vessel 1 equipped with a crawler crane 2 to form an integrated operating platform. A dedicated loading area 3 is set up on the deck of the large vessel 1 to temporarily buffer components. Continuous offshore lifting operations are carried out during the downtime between port replenishment by transport ships. This changes the traditional operation mode where transfer and lifting are completely separated, effectively improving the problems of idle crane equipment and low utilization rate of ship machinery in traditional construction. It reduces the dependence of construction progress on the rhythm of transport ship travel, and can complete offshore steel structure lifting operations without relying on dedicated offshore crane vessels. This reduces the dependence on special vessel resources and project construction investment in offshore construction. Simultaneously, by buffering and storing construction materials in advance, the impact of sea state fluctuations and ship berthing delays on construction procedures is mitigated, ensuring the continuity of lifting operations. It reduces the need for high-frequency coordinated berthing operations by multiple ships, lowers the difficulty of construction management caused by multi-ship cooperation, and adapts to the large-scale and continuous lifting construction needs of offshore photovoltaic projects.

[0036] The above description is merely a preferred embodiment of the present invention and does not limit the scope of the present invention. All equivalent changes made based on the description and drawings of the present invention are included within the scope of the present invention.

Claims

1. A method for hoisting offshore steel structures that combines loading and lifting functions, characterized in that: The pre-configuration of large vessels and crawler cranes follows these steps: S1: Complete the installation and commissioning of the crawler crane at the land terminal, drive the crawler crane to the preset position on the deck of the large ship and fix it, delineate the loading area on the deck of the large ship that is suitable for the working range of the crawler crane, and set up limiting fixtures in the loading area. S2: The large ship equipped with a crawler crane will be sailed to the target lifting point of the steel structure and the hull will be positioned and fixed by the anchoring system equipped on the large ship. S3: The transport ship carrying steel structure components is moored to a large ship, and the steel structure components on the transport ship are lifted by a crawler crane to the loading area for temporary storage. The steel structure components are protected by limiting fixtures. S4: The transport ship returns to the port empty to replenish its cargo. During the round trip of the transport ship, the crawler crane accurately lifts the steel structure components in the loading area to the preset installation points at sea. S5: After the transport ship is fully loaded with components and berths again, the operation process from S3 to S4 is repeated to form a continuous cycle of hoisting operation mode until all steel structure components are hoisted.

2. The offshore steel structure hoisting method with both loading and lifting functions according to claim 1, characterized in that: The load-bearing hub of the crawler crane is welded with an upper connecting seat, and a connecting screw is installed inside the upper connecting seat. Multiple positioning seats are welded on the deck of a large ship, and the bottom end of the connecting screw is provided with a lower connecting seat that is connected to the relative positioning seat.

3. The offshore steel structure hoisting method with both loading and lifting functions according to claim 1, characterized in that: The loading area is laid out along the slewing radius of the crawler crane.

4. The offshore steel structure hoisting method with both loading and lifting functions according to claim 1, characterized in that: The anchoring system in S2 adopts a multi-point anchoring layout.

5. The offshore steel structure hoisting method with both loading and lifting functions according to claim 1, characterized in that: In S4, large ships are equipped with a ship attitude monitoring system. When the crawler crane is lifting, it works in conjunction with the ship attitude monitoring system to achieve precise alignment and installation of components through luffing and slewing adjustments.

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