Prestressed steel strand and flexible photovoltaic support system

Abstract

The utility model relates to the field of solar photovoltaic technology, in particular to a prestressed steel strand and a flexible photovoltaic support system. In the prestressed steel strand, a plurality of outer-layer wires are spirally wound on the outer side of a center wire, and an anti-corrosion material layer is arranged in a gap between the center wire and the outer-layer wires; and the outer-layer wires are weather-proof material pieces. The prestressed steel strand is of a single-layer wrapping structure composed of a single center wire and a plurality of outer layer wires, and the material cost and the machining difficulty can be effectively controlled. The outer-layer wires in the prestressed steel strands are weather-proof steel parts, have the anti-corrosion capacity and are free of the problem of ultraviolet aging; the anti-corrosion material layer further plays an anti-corrosion role on the center wire and resists atmospheric corrosion; the outer layer wire surrounds the whole center wire, the anti-corrosion material layer is protected, the anti-corrosion material layer can be prevented from aging, cracking and losing efficacy under ultraviolet irradiation, and then the anti-corrosion effect of the anti-corrosion material layer on the center wire is guaranteed.

Description

Technical Field

[0001] The utility model relates to the technical field of solar photovoltaics, and in particular to a prestressed steel strand and a flexible photovoltaic support system. Background Art

[0002] The flexible photovoltaic support system is a large-span multi-span structure that uses prestressed steel strands between the two fixed points as the main support, which increases the span between the supporting columns by 5-10 times from 6 meters of the purlin type to more than 30 meters, greatly improving the adaptability to photovoltaic installation scenarios. The flexible photovoltaic support system is suitable for application scenarios such as hillsides, swamps, and water treatment plants.

[0003] The prestressed steel strands used in existing photovoltaic projects are generally single-strand steel strands due to structural and cost constraints. The surface corrosion resistance of single-strand steel strands relies on the hot-dip galvanizing layer to resist atmospheric corrosion, or on the anti-ultraviolet ability of the epoxy resin layer or polyethylene layer on the outside of the single-strand steel strand. However, the thickness of the hot-dip galvanizing layer and the material properties of the epoxy resin layer or polyethylene layer cannot meet the corrosion protection requirements of the corresponding years of photovoltaic power generation equipment. Utility Model Content

[0004] In view of this, the utility model aims to propose a prestressed steel strand and a flexible photovoltaic support system to solve the problem that the existing prestressed steel strand cannot meet the anti-corrosion requirements of photovoltaic power generation equipment for a corresponding period of time due to structural and cost limitations.

[0005] In order to achieve the above object, the technical solution of the utility model is implemented as follows:

[0006] In a first aspect, an embodiment of the utility model provides a prestressed steel strand, which includes a central wire, an anti-corrosion material layer and a plurality of outer wires; the plurality of outer wires are spirally wound around the outside of the central wire, and the anti-corrosion material layer is arranged in the gap between the central wire and the outer wires; the outer wires are weather-resistant material parts.

[0007] Optionally, the strength of the central wire is greater than the strength of the outer wire.

[0008] Optionally, the strength range of the central wire is 2100 MPa-2400 MPa.

[0009] Optionally, the strength range of the outer layer wire is 1300 MPa-2100 MPa.

[0010] Optionally, the diameter of the central wire ranges from 5 mm to 10 mm.

[0011] Optionally, the outer layer wire has a diameter ranging from 3 mm to 5 mm.

[0012] Optionally, the outer wire is made of weathering steel.

[0013] Optionally, the anti-corrosion material layer is an epoxy resin anti-corrosion material layer.

[0014] Optionally, the outer surface of the central wire is provided with a zinc layer; and / or the outer surface of the outer layer wire is provided with a zinc layer.

[0015] In a second aspect, an embodiment of the utility model further provides a flexible photovoltaic support system, which includes support columns and the above-mentioned prestressed steel strands, wherein the prestressed steel strands connect at least two adjacent support columns, and the prestressed steel strands are used to install photovoltaic modules.

[0016] The utility model discloses a prestressed steel strand, in which the central wire is a high-strength steel wire, which mainly bears the tensile force. The outer wire is a medium-strength steel wire made of weather-resistant steel material, which mainly bears the anti-corrosion performance, and the outer wire can also bear a certain tensile force. The strength of the prestressed steel strand in the embodiment of the present application is mainly based on the central wire and supplemented by the outer wire, ensuring that the overall tensile strength of the prestressed steel strand meets the use requirements. The prestressed steel strand is a single-layer coating structure of a single central wire and multiple outer wires, which can effectively control material costs and processing difficulty. The prestressed steel strand has a four-layer anti-corrosion structure. First, the outer wire is made of weather-resistant steel. The outer wire itself has anti-corrosion ability and does not have the problem of aging due to ultraviolet rays. Second, the outer surface of the central wire is provided with a zinc layer, and the outer surface of the outer wire is provided with a zinc layer, which can play an anti-corrosion role. Third, an anti-corrosion material layer is provided in the gap between the central wire and the outer wire, and the anti-corrosion material layer further plays an anti-corrosion role on the central wire, and resists atmospheric corrosion. Fourth, the outer wire surrounds the entire central wire to protect the anti-corrosion material layer, which can prevent the anti-corrosion material layer from aging, cracking, and failure under ultraviolet radiation, thereby ensuring the anti-corrosion effect of the anti-corrosion material layer on the central wire. In summary, the prestressed steel strand of the embodiment of the present application has the characteristics of high strength and good relaxation performance, and has good resistance to atmospheric corrosion and ultraviolet radiation, and can also achieve low-cost overall corrosion protection.

[0017] The above description is only an overview of the technical solution of the utility model. In order to more clearly understand the technical means of the utility model, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for describing the embodiments are briefly introduced below.

[0019] Figure 1It is a structural schematic diagram of a cross-section of the prestressed steel strand described in an embodiment of the utility model.

[0020] Description of reference numerals:

[0021] 10 – center wire; 20 – outer wire; 30 – anti-corrosion material layer. DETAILED DESCRIPTION

[0022] The exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can also be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0023] The utility model embodiment discloses a prestressed steel strand, referring to Figure 1 , which shows a schematic diagram of the structure of a prestressed steel strand provided by an embodiment of the utility model. The prestressed steel strand comprises a central wire 10, an anticorrosive material layer 30 and a plurality of outer wires 20; the plurality of outer wires 20 are spirally wound around the outer side of the central wire 10, and the anticorrosive material layer 30 is arranged in the gap between the central wire 10 and the outer wire 20; the outer wire 20 is a weather-resistant material.

[0024] A plurality of outer wires 20 are spirally wound around the outside of the central wire 10, referring to Figure 1 As shown, a plurality of outer wires 20 form a protective layer around the outer circumference of the central wire 10. The outer wires 20 surround the outer circumference of the central wire 10 at a certain twist angle or twist length, and the outer wires 20 are tangent to the outer circumference of the central wire 10 and the outer circumferences of two adjacent outer wires 20.

[0025] In the prestressed steel strand of the embodiment of the present application, a plurality of outer wires 20 are spirally wound around the periphery of the central wire 10, and an anti-corrosion material layer 30 is arranged in the gap between the central wire 10 and the outer wire 20. The outer wire 20 is a weather-resistant material piece, which has good weather resistance and anti-corrosion ability, and can protect the central wire 10 from atmospheric corrosion; the anti-corrosion material layer 30 is located in the gap between the central wire 10 and the outer wire 20, which can further protect the central wire 10 from atmospheric corrosion. Moreover, the outer wire 20 wraps the anti-corrosion material layer 30, and the outer wire 20 can also protect the anti-corrosion material layer 30 from ultraviolet radiation, thereby protecting the anti-corrosion material layer 30, so that the anti-corrosion material layer 30 maintains the function of isolating the central wire 10 from air corrosion. The prestressed steel strand of the embodiment of the present application, only one circle of outer wire 20 is arranged on the periphery of the central wire 10, has the advantage of low cost, and has good anti-atmospheric corrosion and anti-ultraviolet radiation ability, and meets the anti-corrosion requirements of the corresponding years of photovoltaic power generation equipment at a low cost.

[0026] Among them, the corresponding service life of the photovoltaic power generation equipment is set according to the design requirements. For example, the corresponding service life of the photovoltaic power generation equipment is 25 years, and the prestressed steel strands in the embodiment of the present application can meet the anti-corrosion requirements for 25 years.

[0027] The number of outer wires 20 is set according to the use requirements, and the embodiment of the present application does not specifically limit this. For example, refer to Figure 1 As shown, nine outer wires 20 are provided.

[0028] Optionally, the strength of the central wire 10 is greater than the strength of the outer wire 20 .

[0029] At this time, the central wire 10 has high strength and mainly bears the tensile force. The outer wire 20 is a weather-resistant material. The outer wire 20 mainly bears the anti-corrosion performance of the prestressed steel strand, and the secondary function of the outer wire 20 is to share the tensile force. The above structure of the prestressed steel strand can save costs while meeting the requirements of tensile resistance and service life.

[0030] Optionally, the strength of the central wire 10 is in the range of 2100 MPa to 2400 MPa.

[0031] In the embodiment of the present application, the specific strength of the center wire 10 can be set according to the usage requirements. For example, the strength of the center wire 10 is 2100 MPa; the strength of the center wire 10 is 2150 MPa; the strength of the center wire 10 is 2200 MPa; the strength of the center wire 10 is 2250 MPa; the strength of the center wire 10 is 2300 MPa; the strength of the center wire 10 is 2350 MPa; the strength of the center wire 10 is 2400 MPa.

[0032] Optionally, the strength of the outer layer filament 20 is in the range of 1300 MPa to 2100 MPa.

[0033] In the embodiment of the present application, the specific strength of the outer layer wire 20 can be set according to usage requirements. For example, the strength of the outer layer wire 20 is 1300 MPa; the strength of the outer layer wire 20 is 1400 MPa; the strength of the outer layer wire 20 is 1550 MPa; the strength of the outer layer wire 20 is 1700 MPa; the strength of the outer layer wire 20 is 1800 MPa; the strength of the outer layer wire 20 is 1950 MPa; the strength of the outer layer wire 20 is 2100 MPa.

[0034] In the embodiment of the present application, when the strength of the central wire 10 is within the above range, and the strength of the outer wire 20 is within the above range, the strength of the prestressed steel strand meets the requirements for use in a flexible photovoltaic support system.

[0035] Optionally, the diameter of the center wire 10 is in the range of 5 mm to 10 mm. The diameter of the center wire 10 affects the cost of the prestressed steel strand. When the diameter of the center wire 10 is in the above range, the strength requirement of the prestressed steel strand can be met while the cost requirement of the prestressed steel strand is met.

[0036] In the embodiment of the present application, the specific diameter of the center wire 10 can be set according to usage requirements, for example, the diameter of the center wire 10 is 5mm; the diameter of the center wire 10 is 6mm; the diameter of the center wire 10 is 7mm; the diameter of the center wire 10 is 7.5mm; the diameter of the center wire 10 is 8mm; the diameter of the center wire 10 is 9mm; the diameter of the center wire 10 is 10mm.

[0037] Optionally, the diameter of the outer wire 20 is in the range of 3 mm to 5 mm. The diameter of the outer wire 20 will affect the cost of the prestressed steel strand. When the diameter of the outer wire 20 is in the above range, the strength requirement of the prestressed steel strand can be met while the cost requirement of the prestressed steel strand is met.

[0038] In the embodiment of the present application, the specific diameter of the outer layer wire 20 can be set according to usage requirements. For example, the diameter of the outer layer wire 20 is 3mm; the diameter of the outer layer wire 20 is 3.3mm; the diameter of the outer layer wire 20 is 3.6mm; the diameter of the outer layer wire 20 is 4mm; the diameter of the outer layer wire 20 is 4.3mm; the diameter of the outer layer wire 20 is 4.5mm; the diameter of the outer layer wire 20 is 5mm.

[0039] Optionally, in a specific embodiment, the diameter range of the central wire 10 is 5mm-10mm, the diameter range of the outer wire 20 is 3mm-5mm, and in the selection of prestressed steel strands, the diameter of the outer wire 20 is also 50%-60% of the diameter of the central wire 10.

[0040] Optionally, the outer wire 20 is made of weathering steel.

[0041] Among them, weathering steel parts are a special kind of steel. Weathering steel refers to a low-alloy steel with good atmospheric corrosion resistance made by adding a certain amount of Cu, P, C or Ni, Mo, Nb, Ti and other alloy elements to steel. In industrial and rural atmospheric environments, weathering steel forms a dense and stable oxide protective film on the surface of its matrix, which hinders the entry of corrosive media and has excellent atmospheric corrosion resistance and other properties. Weathering steel parts have high-quality mechanical properties, including toughness, plasticity, formability, weldability, wear resistance and high temperature performance, as well as good fatigue resistance. When the outer wire 20 is made of weathering steel, the outer wire 20 is suitable for long-term exposure to the atmospheric environment, has good atmospheric corrosion resistance, and has good ultraviolet resistance.

[0042] Optionally, the anti-corrosion material layer is an epoxy resin anti-corrosion material layer 30 .

[0043] The epoxy resin anti-corrosion material layer 30 has good corrosion resistance, can effectively resist corrosive media, and can also effectively resist oxidation, thereby ensuring the service life of the center wire 10, and greatly extending the service life of the prestressed steel strand. In addition, the epoxy resin anti-corrosion material layer 30 also has the characteristics of high temperature resistance, impact resistance, scratch resistance, etc., can withstand various climatic conditions, and has good tensile strength and bending strength, which can meet the application requirements of prestressed steel strands in flexible photovoltaic support systems. It is understandable that the anti-corrosion material layer can also be other anti-corrosion material layers that meet the use requirements and have anti-corrosion properties and a certain toughness.

[0044] Optionally, the outer surface of the central wire 10 is provided with a zinc layer, which can improve the anti-corrosion ability of the central wire 10. In addition to mainly bearing the tensile force, the central wire 10 can also bear a certain anti-corrosion ability.

[0045] Optionally, a zinc layer is provided on the outer surface of the outer layer wire 20. The zinc layer can further improve the anti-corrosion ability of the outer layer wire 20.

[0046] In the embodiment of the present application, the center wire 10 and the outer wire 20 can be hot-dip galvanized to form a zinc layer on the outer surface of the center wire 10 and a zinc layer on the outer surface of the outer wire 20. The thickness of the zinc layer ranges from 10um to 17um. For example, the thickness of the zinc layer is 10um; the thickness of the zinc layer is 12um; the thickness of the zinc layer is 15um; the thickness of the zinc layer is 16um; the thickness of the zinc layer is 17um.

[0047] The manufacturing method of the prestressed steel strand in the embodiment of the present application is as follows:

[0048] A central wire 10 that meets the strength requirement is selected (the strength range of the central wire 10 is, for example, 2100 MPa-2400 MPa), and an outer wire 20 that meets the strength requirement is selected (the strength range of the outer wire 20 is, for example, 1300 MPa-2100 MPa).

[0049] With the center wire 10 as the center, the outer wire 20 is twisted around the center wire 10 to produce a steel strand. In this step, the center wire 10 and the outer wire 20 are hot-dip galvanized, drawn after galvanizing, twisted, stabilized, and finally layered, so that the outer wire 20 is spirally wound around the periphery of the center wire 10.

[0050] Then, epoxy resin is coated between the outer wire 20 and the center wire 10. In this step, the steel strand is introduced into the dipping tank, and the steel strand is rotated in the opposite direction of the twist angle of the outer wire 20, so that the gap between the outer wire 20 and the center wire 10 is enlarged, and the liquid epoxy resin enters the area of ​​the center wire 10 and forms a coating on the center wire 10. After the steel strand is loosened, the outer wire 20 is restored to the initial state of being tightly wrapped with the center wire 10, and the excess epoxy resin is squeezed onto the surface of the outer wire 20. The epoxy resin on the outer layer of the steel strand is cleaned. The steel strand is heated to cure the epoxy resin to form an epoxy resin anticorrosive material layer 30.

[0051] In the prestressed steel strand of the embodiment of the present application, the central wire 10 is a high-strength steel wire, which mainly bears the tensile force. The outer wire 20 is a medium-strength steel wire made of weathering steel material, which mainly bears the anti-corrosion performance. The outer wire 20 can also bear a certain tensile force. The strength of the prestressed steel strand of the embodiment of the present application is mainly based on the central wire 10, and the outer wire 20 is supplementary, ensuring that the overall tensile strength of the prestressed steel strand meets the use requirements.

[0052] The prestressed steel strand in the embodiment of the present application has a single-layer coating structure of a single center wire 10 and a plurality of outer wires 20, which can effectively control material costs and processing difficulty.

[0053] The prestressed steel strand has a four-layer anti-corrosion structure. First, the outer wire 20 is made of weather-resistant steel. The outer wire 20 itself has anti-corrosion ability and does not have the problem of aging due to ultraviolet rays. Second, the outer surface of the central wire 10 is provided with a zinc layer, and the outer surface of the outer wire 20 is provided with a zinc layer, which can play an anti-corrosion role. Third, an anti-corrosion material layer 30 is provided in the gap between the central wire 10 and the outer wire 20. The anti-corrosion material layer 30 further plays an anti-corrosion role on the central wire 10 and resists atmospheric corrosion. Fourth, the outer wire 20 surrounds the entire central wire 10 to protect the anti-corrosion material layer 30, which can prevent the anti-corrosion material layer 30 from aging, cracking, and failure under ultraviolet rays, thereby ensuring the anti-corrosion effect of the anti-corrosion material layer 30 on the central wire 10.

[0054] The above structure of the prestressed steel strand of the embodiment of the present application has the characteristics of high strength and good relaxation performance, and has good resistance to atmospheric corrosion and ultraviolet radiation. The prestressed steel strand achieves low-cost overall corrosion protection through the above structure, which can meet the 25-year life requirement of photovoltaic equipment.

[0055] Among them, steel strand is a kind of steel cable. Steel strand is a steel product composed of multiple steel wires twisted together. The surface of carbon steel can be added with galvanized layer, zinc-aluminum alloy layer, aluminum clad layer, copper plating layer, epoxy coated layer, etc. as needed.

[0056] Prestressed steel strand is a twisted steel cable consisting of 2, 3, 7 or 19 high-strength steel wires, and has been stress-relieved (stabilized). The main characteristics of prestressed steel strand are high strength and good relaxation performance, and it is relatively straight when stretched.

[0057] Atmospheric corrosion refers to the corrosion of metals in the natural environment of the atmosphere. Oxygen, sulfur dioxide, and salt particles are the main corrosive elements.

[0058] The utility model embodiment also discloses a flexible photovoltaic support system, which includes support columns and the above-mentioned prestressed steel strands, the prestressed steel strands connect at least two adjacent support columns, and the prestressed steel strands are used to install photovoltaic components.

[0059] In the flexible photovoltaic support system, the span between the supporting columns is more than 8 meters, and the above-mentioned prestressed steel strands with a certain flexibility are used as support members for photovoltaic modules between adjacent supporting columns.

[0060] Photovoltaic modules generally refer to solar cell modules, which are a certain number of single-chip solar cells sealed together in series and parallel to prevent corrosion of the cell electrodes and interconnections, to prevent the cells from breaking, and to facilitate outdoor installation.

[0061] The flexible photovoltaic support system of the embodiment of the utility model uses prestressed steel strands as the support of the photovoltaic module. The prestressed steel strands have the characteristics of high strength and good relaxation performance, and have good resistance to atmospheric corrosion and ultraviolet radiation. The prestressed steel strands have low-cost overall corrosion resistance and can meet the 25-year life requirement of photovoltaic equipment, so that the flexible photovoltaic support system meets the 25-year life requirement of photovoltaic equipment.

[0062] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0063] Each embodiment in this specification is described in a related manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. For the embodiments of the device, electronic device, computer-readable storage medium and computer program products containing instructions, since they are basically similar to the method embodiments, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiments.

[0064] The above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. A prestressed steel strand, characterized in that: It comprises a central wire (10), an anti-corrosion material layer (30) and a plurality of outer wires (20); the plurality of outer wires (20) are spirally wound around the outer side of the central wire (10), and the anti-corrosion material layer (30) is arranged in the gap between the central wire (10) and the outer wire (20); the outer wire (20) is a weather-resistant material.

2. The prestressed steel strand according to claim 1, characterized in that: The strength of the central wire (10) is greater than the strength of the outer layer wire (20).

3. The prestressed steel strand according to claim 2, characterized in that: The strength range of the central wire (10) is 2100 MPa-2400 MPa.

4. The prestressed steel strand according to claim 2, characterized in that: The strength of the outer layer wire (20) ranges from 1300 MPa to 2100 MPa.

5. The prestressed steel strand according to claim 1, characterized in that: The diameter of the central wire (10) ranges from 5 mm to 10 mm.

6. The prestressed steel strand according to claim 1, characterized in that: The diameter of the outer layer wire (20) is in the range of 3 mm to 5 mm.

7. The prestressed steel strand according to claim 1, characterized in that: The outer layer wire (20) is made of weathering steel.

8. The prestressed steel strand according to claim 1, characterized in that: The anti-corrosion material layer is an epoxy resin anti-corrosion material layer (30).

9. The prestressed steel strand according to claim 1, characterized in that: The outer surface of the central wire (10) is provided with a zinc layer; and / or the outer surface of the outer layer wire (20) is provided with a zinc layer.

10. A flexible photovoltaic support system, characterized in that: It comprises a supporting column and the prestressed steel strand according to any one of claims 1 to 9, wherein the prestressed steel strand connects at least two adjacent supporting columns and is used for installing photovoltaic modules.

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