Offshore photovoltaic floating type supporting structure based on GFRP winding steel pipe and manufacturing process

Abstract

The invention discloses an offshore photovoltaic floating type supporting structure based on a GFRP winding steel pipe and a manufacturing process, and relates to the technical field of offshore photovoltaic power stations. The supporting structure comprises a GFRP winding steel pipe, wherein the GFRP winding steel pipe comprises a steel pipe, a binder layer and a GFRP winding layer which are sequentially arranged from inside to outside; the steel pipe is made of high-strength grade steel; the GFRP winding layers are made of glass fiber yarns, the number of the GFRP winding layers is 3-10, the thickness of a single GFRP winding layer is 0.2 mm-0. 6mm, the winding angle of each GFRP winding layer is 15-85 degrees, and the binder layer is made of high-strength structural adhesive. The manufacturing process of the supporting structure comprises the three steps of steel pipe surface treatment, GFRP winding and GFRP curing. The GFRP is used for manufacturing the protective layer to wrap the steel pipe, the steel pipe is prevented from being directly exposed in a corrosion environment, the service life of the steel pipe can be effectively prolonged, and the bearing capacity of the component can be improved on the premise that the self weight of the component is basically not increased through GFRP winding.

Description

Technical Field

[0001] The present invention belongs to the technical field of offshore photovoltaic power stations, and specifically relates to an offshore photovoltaic floating support structure based on GFRP wound steel pipes and a manufacturing process thereof. Background Art

[0002] With the continuous growth of global energy demand and the intensification of environmental pollution, the development of clean and renewable energy has become a global consensus. Offshore photovoltaics has become a key development direction of renewable energy due to its advantages such as high power generation, less land resource occupation and little impact on the ecological environment.

[0003] Offshore photovoltaic power stations are composed of floating support structures, photovoltaic modules, power transmission systems, mooring systems, etc. As the main force-bearing structure, the reliability of the floating support structure is an important prerequisite for ensuring the normal operation of offshore photovoltaic power stations. However, the severe corrosion phenomenon and complex load conditions in the marine environment have a serious impact on the reliability of the floating support structure. At the same time, due to the high construction cost, the development of offshore photovoltaics has been seriously hindered.

[0004] The existing floating support structure is mainly based on the design method of galvanized steel pipe components. Carbon steel pipes with appropriate diameter and wall thickness are selected as the main structure. A protective layer is formed on the outer wall of the steel pipe through hot-dip galvanizing or electro-galvanizing to improve the corrosion resistance of the structure. The galvanized steel pipe is connected by welding or machine connection, and the connection parts are treated with additional anti-corrosion coating. After installation, the integrity of the coating is regularly checked and repaired. Although the existing floating support structure design method based on galvanized steel pipe components meets the corrosion resistance and load-bearing requirements to a certain extent, it has obvious limitations in practical applications: ① The service life of offshore photovoltaic power stations is usually greater than 25 years, while the corrosion resistance life of the galvanized layer is usually 10-15 years, and the galvanized layer is easily damaged at the welding part or the machine connection part, resulting in local corrosion; ② The galvanized layer will increase the deadweight of the structure and thus increase the load-bearing burden of the floating pipe.

[0005] Based on this, the present invention proposes an offshore photovoltaic floating support structure based on GFRP wrapped steel pipe and a manufacturing process to solve the above technical problems. Summary of the invention

[0006] The present invention provides an offshore photovoltaic floating support structure based on GFRP wrapped steel pipe and a manufacturing process, the purpose of which is to improve the corrosion resistance of the structure and achieve lightweight design while meeting the structural strength requirements.

[0007] The present invention provides an offshore photovoltaic floating support structure based on GFRP wound steel pipe, which adopts the following technical solutions: An offshore photovoltaic floating support structure based on a GFRP wrapped steel pipe comprises a GFRP wrapped steel pipe, wherein the GFRP wrapped steel pipe comprises a steel pipe, an adhesive layer, and a GFRP wrapped layer arranged in sequence from the inside to the outside; the GFRP wrapped layer is wrapped around the outer surface of the steel pipe, and an adhesive layer is coated between the steel pipe and the GFRP wrapped layer; The steel pipe is made of high-strength grade steel; The GFRP winding layer is made of glass fiber yarn, the number of layers of the GFRP winding layer is 3 to 10, the thickness of a single layer of the GFRP winding layer is 0.2 mm to 0.6 mm, and the winding angle of the GFRP winding layer is 15° to 85°; The adhesive layer adopts high-strength structural adhesive.

[0008] Preferably, the steel pipe is made of Q235 steel or Q355 steel.

[0009] Preferably, the GFRP winding layer is made of alkali-free glass fiber roving.

[0010] Preferably, the linear density of the glass fiber yarn is 300 tex to 2400 tex.

[0011] Preferably, the adhesive layer is made of vinyl resin.

[0012] The present invention also provides a manufacturing process of the above-mentioned offshore photovoltaic floating support structure based on GFRP wound steel pipe, which is manufactured by a wet winding process, comprising the following steps: S1. Surface treatment of steel pipe: sandblast the surface of the steel pipe to increase the surface roughness of the steel pipe, then use acetone to clean the oil and dust on the surface of the steel pipe, and then apply a layer of high-strength structural adhesive; S2. GFRP winding: The winding is performed using an automated wet winding device according to the pre-designed number of GFRP winding layers, layer thickness, winding and fiber winding direction; specifically, the glass fiber yarn is drawn from the spool, passes through a bathtub containing high-strength structural adhesive, then passes around a pressure roller, and finally is wound on the steel pipe according to the pre-designed GFRP winding layer parameters; S3.GFRP curing: Curing is carried out according to the performance requirements of the selected high-strength structural adhesive.

[0013] Preferably, in step S2, the winding tension is controlled within a range of 3% to 8% of the fiber tensile strength.

[0014] Preferably, in step S2, the fiber mass proportion in the GFRP winding layer is 60% to 70%.

[0015] Preferably, the GFRP wrapped steel pipe is connected by welding. The welding should avoid the GFRP wrapped layer that has been wound and solidified. For the convenience of connection, 50-100mm of exposed steel pipe should be reserved at the end of the component to ensure the convenience of welding operation and the quality of weld.

[0016] Preferably, after welding is completed, the weld position should be provided with additional corrosion protection, and multiple layers of GFRP cloth should be pasted by hand lay-up process to achieve the protection purpose.

[0017] Beneficial effects of the present invention: (1) Excellent corrosion resistance: By using high-strength steel as the inner steel pipe and wrapping multiple layers of GFRP on its outer surface, combined with a high-performance adhesive layer, the support structure can effectively resist the effects of salt spray, moisture and other corrosive factors in the marine environment. Compared with traditional galvanized steel pipes, GFRP material itself has excellent corrosion resistance and is not as easily damaged at welding or mechanical connections as zinc coating, thus avoiding the problem of local rust.

[0018] (2) Lightweight design and optimized load-bearing capacity: The GFRP wrapping layer not only provides good anti-corrosion protection, but also enhances the rigidity and strength of the entire structure. Since the density of GFRP is much lower than that of steel, the final product can significantly reduce its own weight while maintaining sufficient load-bearing capacity, reduce the requirements for the load-bearing load of the floating pipe, reduce the amount of steel used, and improve the overall efficiency and economy of the system.

[0019] (3) Ability to adapt to complex load conditions: The present invention allows the number of layers, thickness and winding angle of the GFRP winding layer to be adjusted according to actual engineering needs to ensure that the structure can withstand the expected stress distribution in different directions; especially for complex dynamic loads such as waves, currents and wind in the marine environment, this flexibility can better meet the mechanical requirements in specific application scenarios.

[0020] (4) Simplify the manufacturing process and improve the convenience of construction: The wet winding process is used for automated production, which not only ensures the consistency and stability of product quality, but also reduces production costs. In addition, the design of reserved exposed steel pipes at the ends of the components facilitates on-site welding and installation, while providing additional corrosion protection measures for the welds, such as hand-laid GFRP cloth, which further ensures the safety, reliability and long-term service life of the structure.

[0021] (5) Extend service life and reduce maintenance costs: Due to the natural advantages of GFRP materials and reasonable structural design, the support structure is expected to reach or even exceed the 25-year service life required by offshore photovoltaic power stations. During this period, there is no need for frequent inspection and repair of the anti-corrosion coating, which greatly reduces the workload and cost of subsequent maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] For ease of explanation, the present invention is described in detail with reference to the following specific implementations and the accompanying drawings.

[0023] Figure 1 This is a schematic diagram of the structure of the GFRP wrapped steel pipe in this embodiment; Figure 2 This is a process flow chart of preparing GFRP wound steel pipe in this embodiment; Figure 3 This is a schematic diagram of the connection parts of the GFRP wrapped steel pipe in this embodiment.

[0024] In the figure: 1- steel pipe; 2- adhesive layer; 3- GFRP winding layer; 4- bobbin; 5- bathtub; 6- pressure roller. DETAILED DESCRIPTION

[0025] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solutions of the present invention, but the present invention is not limited to these embodiments; in the following description, specific details such as specific configurations and components are provided only to help fully understand the embodiments of the present invention. Therefore, it should be clear to those skilled in the art that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present invention. In addition, for the sake of clarity and brevity, the description of known functions and structures is omitted.

[0026] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features of the embodiments may be combined with each other.

[0027] like Figure 1-Figure 3 As shown, the offshore photovoltaic floating support structure based on the GFRP wrapped steel pipe provided in this embodiment includes a GFRP wrapped steel pipe, and the GFRP wrapped steel pipe includes a steel pipe 1, an adhesive layer 2, and a GFRP wrapped layer 3 arranged in sequence from the inside to the outside; the GFRP wrapped layer 3 is wrapped around the outer surface of the steel pipe 1, and the adhesive layer 2 is coated between the steel pipe 1 and the GFRP wrapped layer 3; Among them, the material selection of steel pipe 1 is based on the actual structural bearing capacity requirements to select the appropriate steel strength grade, the commonly used grades are Q235 and Q355. Considering the lightweight design of the structure, higher strength grade steel can be used to reduce the cross-sectional size. According to the actual engineering needs, the appropriate steel pipe diameter and wall thickness should be selected. When designing the steel pipe section, reference should be made to GB 50017-2017 "Steel Structure Design Standard" to ensure that the steel pipe components have sufficient bearing capacity while ensuring the overall and local stability of the components. The wall thickness of the pipe can be appropriately increased at the welding node position.

[0028] The GFRP wrapping layer 3 uses glass fiber yarn, preferably alkali-free glass fiber untwisted coarse yarn, with a recommended linear density range of 300tex to 2400tex. Other types of glass fiber yarn can also be used according to actual needs; the number of GFRP wrapping layers is 3 to 10 layers, and the number of wrapping layers is appropriately increased according to the bearing capacity and anti-corrosion requirements; the thickness of a single-layer GFRP wrapping layer is related to the density of the glass fiber yarn, generally 0.2mm to 0.6mm; the winding angle of the glass fiber yarn of the GFRP wrapping layer should be optimized according to the stress characteristics of the component and the process requirements. The fiber winding angle that can be achieved by the wet winding process is 15° to 85°. In order to cope with complex load conditions in the marine environment, a winding method with a combination of various angles should be selected.

[0029] The adhesive layer 2 uses high-strength structural adhesive, preferably a vinyl resin with strong seawater corrosion resistance; the high-strength structural adhesive is coated between the steel pipe 1 and the GFRP wrapping layer 3 to ensure effective bonding between the two.

[0030] This embodiment also provides a manufacturing process of the above-mentioned offshore photovoltaic floating support structure based on GFRP wound steel pipe, which is manufactured by a wet winding process, including the following steps: S1. Surface treatment of steel pipe: The surface of the steel pipe 1 is sandblasted to increase the surface roughness of the steel pipe 1, and then the oil and dust on the surface of the steel pipe 1 are cleaned with acetone, and then a layer of high-strength structural adhesive is applied.

[0031] S2. GFRP winding: according to the pre-designed number of GFRP winding layers 3, layer thickness, winding and fiber winding direction, the winding is carried out using an automated wet winding equipment; specifically, the glass fiber yarn is led out from the spool 4, passes through the bathtub 5 containing high-strength structural adhesive, then passes around the pressure roller 6, and finally is wound on the steel pipe according to the above-mentioned pre-designed GFRP winding layer 3 parameters; during winding, the winding tension is controlled at 3% to 8% of the fiber tensile strength, and the fiber mass accounts for 60% to 70% in the GFRP winding layer.

[0032] S3.GFRP curing: Curing is carried out according to the performance requirements of the selected high-strength structural adhesive.

[0033] During the connection and installation, the GFRP wrapped steel pipe is connected by welding. The welding should avoid the GFRP wrapped layer 3 that has been wound and solidified. For the convenience of connection, a 50-100mm exposed steel pipe 1 should be reserved at the end of the component to ensure the convenience of welding operation and the quality of the weld. After the welding is completed, the weld position should be additionally protected from corrosion, and the hand paste process should be used to paste multiple layers of GFRP cloth to achieve the purpose of protection. After the floating photovoltaic support structure is connected on land, it is towed to the designated sea area for installation and fixation.

[0034] Therefore, the present invention uses GFRP to make a protective layer to cover the steel pipe, so as to prevent the steel pipe from being directly exposed to the corrosive environment, and can effectively extend its service life. The density of GFRP is only 1 / 4 of that of steel. By winding with GFRP, the bearing capacity of the component can be improved without substantially increasing the self-weight of the component. Then, by optimizing the design, the amount of steel can be reduced while meeting the structural strength, thereby reducing the self-weight of the structure.

[0035] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0036] In the description of the present application, it should be understood that the terms "upper", "lower", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

Claims

1. An offshore photovoltaic floating support structure based on GFRP wrapped steel pipe, characterized in that: The invention comprises a GFRP wrapped steel pipe, wherein the GFRP wrapped steel pipe comprises a steel pipe (1), an adhesive layer (2), and a GFRP wrapped layer (3) arranged in sequence from the inside to the outside; the GFRP wrapped layer (3) is wrapped around the outer surface of the steel pipe (1), and the adhesive layer (2) is coated between the steel pipe (1) and the GFRP wrapped layer (3); The steel pipe (1) is made of high-strength grade steel; The GFRP winding layer (3) is made of glass fiber yarn, the number of layers of the GFRP winding layer (3) is 3 to 10, the thickness of a single layer of the GFRP winding layer (3) is 0.2 mm to 0.6 mm, and the winding angle of the GFRP winding layer (3) is 15° to 85°; The adhesive layer (2) is made of high-strength structural adhesive.

2. The offshore photovoltaic floating support structure based on GFRP wound steel pipe according to claim 1 is characterized in that: The steel pipe (1) is made of Q235 steel or Q355 steel.

3. The offshore photovoltaic floating support structure based on GFRP wound steel pipe according to claim 1 is characterized in that: The GFRP winding layer (3) is made of alkali-free glass fiber roving.

4. The offshore photovoltaic floating support structure based on GFRP wound steel pipe according to claim 1 is characterized in that: The linear density of the glass fiber yarn is 300 tex to 2400 tex.

5. The offshore photovoltaic floating support structure based on GFRP wound steel pipe according to claim 1 is characterized in that: The adhesive layer (2) is made of vinyl resin.

6. A manufacturing process for an offshore photovoltaic floating support structure based on GFRP wound steel pipe according to any one of claims 1 to 5, characterized in that: The process is wet winding, which includes the following steps: S1. Surface treatment of the steel pipe: sandblasting the surface of the steel pipe (1) to increase the surface roughness of the steel pipe (1), then using acetone to clean the oil and dust on the surface of the steel pipe (1), and then coating it with a layer of high-strength structural adhesive; S2. GFRP winding: winding is performed using an automated wet winding device according to the pre-designed number of GFRP winding layers (3), layer thickness, winding and fiber winding direction; specifically, the glass fiber yarn is drawn from the spool (4), passes through a bathtub (5) containing high-strength structural adhesive, then passes around a pressure roller (6), and finally is wound on the steel pipe according to the pre-designed GFRP winding layer (3) parameters; S3.GFRP curing: Curing is carried out according to the performance requirements of the selected high-strength structural adhesive.

7. The manufacturing process of the offshore photovoltaic floating support structure based on GFRP wound steel pipe according to claim 6 is characterized in that: In step S2, the winding tension is controlled within a range of 3% to 8% of the fiber tensile strength.

8. The manufacturing process of the offshore photovoltaic floating support structure based on GFRP wound steel pipe according to claim 6 is characterized in that: In step S2, the fiber mass proportion in the GFRP winding layer (3) is 60% to 70%.

9. The manufacturing process of the offshore photovoltaic floating support structure based on GFRP wound steel pipe according to claim 6 is characterized in that: The GFRP wrapped steel pipe is connected by welding. The welding should avoid the GFRP wrapped layer that has been wrapped and solidified. For the convenience of connection, 50-100mm of exposed steel pipe should be reserved at the end of the component to ensure the convenience of welding operation and the quality of weld.

10. The manufacturing process of the offshore photovoltaic floating support structure based on GFRP wound steel pipe according to claim 9, characterized in that: After welding is completed, additional corrosion protection should be provided at the weld position, and multiple layers of GFRP cloth should be pasted using a hand-layup process to achieve the protection purpose.

Images