A method for prefabricating a wind turbine blade spar

Abstract

The application discloses a wind power blade girder prefabricating forming method, comprising the following steps: S1, selecting a metal material to process a metal sheet with a preset size; S2, performing oblique cutting machining treatment on both ends of the metal sheet in the length direction, and then performing round hole processing; S3, performing surface treatment on the metal sheet after the round hole processing is completed, so as to enhance the interface bonding strength between the metal sheet and the pouring resin; S4, laying the metal sheet after the surface treatment on a blade girder prefabricating mold according to the requirements of a layer design; S5, laying auxiliary materials such as release cloth, isolation film and a vacuum bag on the well-laid girder material, pressing the vacuum bag, completing resin pouring, increasing the mold temperature to a preset temperature, and solidifying for a preset time, so that solidification forming is completed, and a wind power blade prefabricated metal girder is obtained; and the application realizes the balance between cost reduction and weight increase of the blade girder material by performing different layer design on the metal sheet in the thickness direction of the blade girder.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of prefabricating a main beam of a wind turbine blade using composite material technology, and particularly relates to a method for prefabricating a main beam of a wind turbine blade. BACKGROUND

[0002] With the increasingly fierce competition in the market of complete wind turbines, the demand for reducing the cost of wind turbines is increasingly strong. As one of the key components of wind turbines, blades account for 20-25% of the manufacturing cost of wind turbines, and play a very important role in cost control.

[0003] The development trend of large-scale wind turbine blades can greatly improve the power generation of wind turbines and reduce the cost of electricity. However, in the process of designing longer blades, higher requirements are placed on the stiffness of the blades, and in the case of not significantly increasing the size of the blade airfoil section, higher requirements are placed on the modulus of the blade material. Since the modulus of the material in the 0° direction of the main beam has an important influence on the flapping stiffness of the blade, it is related to the safe operation of the blade, so the modulus in the length direction of the blade needs to be compensated to some extent to reduce the risk of blade operation.

[0004] On the other hand, among various ways to reduce the cost of blades, the application of low-cost materials is an effective means to achieve blade cost reduction, and is also one of the important methods to fundamentally change the existing blade system and solve the problem of high blade material cost. In the design of offshore large blades, in order to ensure that the blades have sufficient mechanical properties, the selection of the main beam material of the blades is often based on carbon fiber pultruded sheets. However, although this material has high mechanical properties and can fully guarantee the safe operation of offshore large blades, it also causes the problem of high cost of blade main beams. In recent years, due to the situation of supply not meeting demand in the application market of carbon fiber, the hot market of carbon fiber has caused its market price to rise, and even once reached a height of 150 yuan / kg. If the main beam material of an offshore large blade above 100 meters is all carbon fiber pultruded sheets, the material will account for more than 50% of the cost of the blade material, so the use of carbon fiber pultruded sheets will cause great pressure on the cost of the blade.

[0005] Therefore, careful consideration is needed in the selection of blade main beam materials, and if other materials that meet the performance requirements of blade main beams and can bring great cost reduction are found, it will have important significance for the cost reduction of blades and even wind turbines. SUMMARY

[0006] The present application aims to overcome the deficiencies of the prior art, and provides a wind power blade main beam prefabrication forming method, which applies a specially treated metal sheet to the lay-up of the blade main beam material, the special treatment of the metal sheet enhances the interfacial bonding strength of the metal lay-up and the pultrusion plate lay-up in contact with the upper and lower, and enhances the interfacial bonding strength with the injected resin, realizes the great cost reduction of the main beam material, achieves the effect of 0° direction stiffness improvement, and simultaneously performs different way lay-up design on the metal sheet in the thickness direction of the blade main beam, realizes the balance between the cost reduction and weight increase of the blade main beam material.

[0007] To achieve the above object, the technical scheme provided by the present application is as follows: a wind power blade main beam prefabrication forming method, comprising the following steps:

[0008] S1, selecting a metal material to process a metal sheet with a predetermined size;

[0009] S2, performing inclined cutting machining treatment on both ends of the metal sheet in the length direction, and then performing round hole processing;

[0010] S3, performing surface treatment on the metal sheet after the round hole processing is completed, so as to enhance the interfacial bonding strength between the metal sheet and the injected resin;

[0011] S4, laying the metal sheet after the surface treatment on a blade main beam prefabrication mold according to the lay-up design requirements;

[0012] S5, laying release cloth, isolation film and vacuum bag auxiliary materials on the laid main beam material, pressing the vacuum bag, completing resin injection, increasing the mold temperature to a predetermined temperature, and curing for a predetermined time to complete curing forming, and obtaining a wind power blade prefabricated metal main beam.

[0013] Further, the metal material is one or more of stainless steel, aluminum alloy and titanium alloy.

[0014] Further, the step S1 comprises the following steps:

[0015] The metal material is selected to process a metal sheet with a required size, the size specification of the metal sheet is processed according to the design requirements of different lay-ups of the main beam, and finally curled into a metal coil with a predetermined length, wherein the length of the metal sheet ranges from 100m to 200m, the width ranges from 0.5m to 2.0m, and the thickness ranges from 0.1mm to 3.0mm.

[0016] Further, the step S2 comprises the following steps:

[0017] Both ends of the metal sheet in the length direction are subjected to inclined cutting machining treatment, and the chamfering range is 1:50-1:200, and the chamfering edge is polished smooth with sandpaper;

[0018] The metal sheet is punched with round holes, and the round holes are spaced at the same distance, and the hole diameter of the round holes ranges from 1 mm to 3 mm, and the hole distance of the round holes ranges from 20 mm to 40 mm.

[0019] Further, the step S3 comprises the following steps:

[0020] The metal sheet is surface treated to enhance the interfacial bonding strength between the metal sheet and the infusion resin, wherein the surface treatment method is selected from one or more of the following methods: sandpaper polishing, sandblasting, acid pickling, phosphating, flame treatment, silane coupling agent treatment, etc.

[0021] Sandpaper polishing: the sandpaper fineness is selected from 36# to 150#, and the metal sheet is polished twice on the front and back surfaces to increase the roughness of the metal sheet surface, increase the contact area between the resin and the metal sheet, and further increase the interfacial bonding strength.

[0022] Sandblasting treatment: carried out on a sandblasting machine, the sandblasting is selected from one of the following: diamond sand, quartz sand, and iron sand, the sandblasting particle size is 50 mesh to 200 mesh, the average particle size is 0.2 mm to 0.8 mm, the compressed air pressure during sandblasting is 0.6 MPa to 0.85 MPa, the sandblasting distance is 80 mm to 120 mm, and the sandblasting angle is 70° to 85°; under the impact of high-speed sand particles, the substrate of the metal sheet deforms and the crystal slips, irregular pits without fixed orientation are formed on the metal surface, and the anisotropic surface increases the contact area.

[0023] Acid pickling treatment: the metal sheet is polished with 800# sandpaper, then degreased with acetone, and then immersed in an 18% hydrochloric acid solution at room temperature, soaked for 10 min to 30 min, taken out, washed with deionized water, and dried with hot air at 60°C.

[0024] Phosphating treatment: the metal sheet is polished with 800# sandpaper, and then immersed in a zinc-based phosphating solution at room temperature, soaked for 10 min to 30 min, taken out, washed with deionized water, and dried with hot air at 60°C.

[0025] Flame treatment: the flame spray gun is aimed at the surface of the metal sheet at a distance of 20 cm to 30 cm, and the gun is moved uniformly and slowly, so that the surface temperature of the metal sheet reaches 900°C to 1000°C instantaneously, a layer of metal oxide film is generated on the surface, and polar functional groups are generated, which are beneficial to improving the interfacial bonding strength between the metal and the resin.

[0026] Silane coupling agent treatment: Add ethanol to deionized water and stir well. Add 0.5%-2.0% KH550 silane coupling agent by mass and adjust the pH to 8-10 with 10% nitrous acid solution to obtain the coupling agent solution. First, polish the surface of the metal sheet with 800# sandpaper and remove oil with acetone. Then, immerse the sample in the coupling agent solution at room temperature for 10-30 minutes, take it out, and dry it in an oven at 200℃-250℃ for 30-60 minutes to obtain a silane film on the metal surface.

[0027] Furthermore, step S4 includes the following steps:

[0028] The processed metal sheets are laid together with pultruded plates on the precast mold of the wind turbine blade main beam according to the layup design requirements; wherein, the width of the pultruded plate ranges from 60mm to 180mm, the thickness ranges from 3mm to 6mm, and the pultruded plate is one or more of glass fiber pultruded plate, carbon fiber pultruded plate, and carbon-glass hybrid pultruded plate.

[0029] In the thickness direction of the main beam, the metal sheets and pultruded plates are laid according to the pre-designed arrangement requirements, which include the following three types: 1) the metal sheets and pultruded plates are arranged alternately, that is, a pultruded plate is placed between every two layers of metal sheets; 2) the metal sheets and pultruded plates are arranged in an up-down manner; 3) the metal sheets and pultruded plates are arranged in an increasing or decreasing manner.

[0030] If the main beam material of the same layer is a metal sheet, then only one metal sheet is included in the width direction; if the main beam material of the same layer is a pultruded plate, then multiple pultruded plates can be included in the width direction, and the pultruded plates are spliced ​​together; the two ends of the pultruded plate in the length direction are also beveled, and the chamfer size is consistent with that of the metal sheet.

[0031] The volume ratio of metal sheet to pultruded plate is 100:0-100:500. When it is 100:0, it means that the main beam uses metal sheet material throughout. A layer of flow-guiding fabric is added between different upper and lower layers to facilitate the smooth flow of resin between layers during subsequent vacuum resin infusion. The material of the flow-guiding fabric is glass fiber, and the basis weight range of the flow-guiding fabric is 100 g / m². 2 -400g / m 2 .

[0032] Furthermore, step S5 includes the following steps:

[0033] The auxiliary material laying of release cloth, isolation film and vacuum bag is carried out on the laid main beam material, the vacuum bag is pressed down, the resin is poured, the mold temperature is increased to 70-90 DEG C, and curing is carried out for 4-10 hours, the curing molding is completed, and the wind power blade prefabricated metal main beam is obtained, wherein the pouring resin is one of epoxy resin, unsaturated polyester resin, polyurethane resin and vinyl resin.

[0034] Compared with the prior art, the present application has the following advantages and beneficial effects:

[0035] 1. The present application introduces metal sheet laying material into the wind power blade main beam, the metal sheet material is low in cost and easy to obtain, has a wide application space, replaces the expensive pultrusion plate material entirely or partially, produces certain economic benefits, realizes the substantial reduction of the wind power blade manufacturing cost, and simultaneously, the high modulus of the metal material in the 0 direction can improve the modulus of the blade main beam under the unit weight and unit cost, is beneficial to the structural design of the main beam, and in addition, the metal material is easy to recycle, can reduce resource waste and environmental pollution.

[0036] 2. The present application simultaneously carries out two design modes of metal sheet and pultrusion plate composite laying of the blade main beam; when the main beam material is all metal sheet, the high modulus mechanical properties and low cost advantages of the metal material are maximized, and when the main beam material is metal sheet and pultrusion plate mixed use, the comprehensive performance of the high modulus, low cost of the metal material and the overall low weight of the main beam is considered, and the balance between the performance, cost and weight is realized.

[0037] 3. The present application carries out different processing designs on the metal sheet laying, is beneficial to the interfacial bonding performance of the metal sheet and the pouring resin, reduces the risk of failure, and improves the operability of the pouring process, wherein the punching design of the metal sheet is beneficial to more efficient pouring efficiency, simultaneously enhances the interfacial bonding strength of the metal laying and the pultrusion plate laying in contact with the upper and lower, and does not affect the structural performance of the metal sheet; and the surface treatment of the metal sheet is also carried out to enhance the interfacial bonding strength of the metal sheet and the pouring resin, thereby improving the interlaminar shear performance. BRIEF DESCRIPTION OF DRAWINGS

[0038] Figure 1 It is a structural schematic view of the metal sheet which has been chamfered.

[0039] Figure 2 It is a structural schematic view of the metal sheet which has been punched.

[0040] Figure 3 It is a structural sectional view of the metal sheet and the pultrusion plate which are alternately arranged.

[0041] Figure 4A side view of a structure with alternating metal sheets and pultruded plates.

[0042] Figure 5 This is a cross-sectional view of a structure in which thin metal sheets and pultruded plates are arranged in an upper and lower configuration.

[0043] Figure 6 A side view of a structure in which thin metal sheets and pultruded plates are arranged vertically.

[0044] Figure 7 This is a cross-sectional view of a structure in which metal sheets and pultruded plates are arranged in an increasing manner.

[0045] Figure 8 A side view of a structure in which metal sheets and pultruded plates are arranged in an incremental manner. Detailed Implementation

[0046] The present invention will be further described below with reference to specific embodiments.

[0047] Example 1

[0048] This embodiment provides a method for prefabricating the main beam of a wind turbine blade, including the following steps:

[0049] S1. Select 304 stainless steel sheet material and process it into a length of 110m, a width of 0.6m, and a thickness of 0.8mm according to the layup design requirements;

[0050] S2, see also Figure 1 As shown, the two ends 2 along the length of the metal sheet 1 are beveled, with a chamfer of 1:100. The chamfered edges are then sanded smooth. (See also...) Figure 2 As shown, the metal sheet 1 is drilled with round holes 3, with a hole diameter of 2mm and a hole spacing of 30mm.

[0051] S3. Perform phosphating surface treatment on the metal sheet. First, polish with 800# sandpaper, then immerse the metal sheet in a zinc-based phosphating solution at room temperature for 20 minutes. After soaking, remove it, rinse with deionized water, and dry with hot air at 60°C.

[0052] S4. The processed metal sheets, along with the carbon fiber pultruded plates, are laid onto the blade main beam precast mold according to the layup design requirements. Each pultruded plate is 120mm wide and 4.8mm thick. Five pultruded plates 4 are laid per layer on the main beam, using a splicing method, maintaining the same width as the metal sheet 1 overall. (See also...) Figures 3-4As shown, in the thickness direction of the main beam, the metal sheet 1 and the pultruded plate 4 are arranged alternately, and one layer of the pultruded plate 4 is arranged between every two layers of the metal sheet 1. The two ends of the pultruded plate 4 in the length direction are also subjected to the inclined cutting machining treatment, and the size of the chamfer is consistent with that of the metal sheet 1. The volume ratio of the metal sheet 1 to the pultruded plate 4 is 100:300. A layer of flow guide fabric is added between the metal sheets in the upper and lower layers and between the metal sheets and the pultruded plate, so as to facilitate the smooth flow of the resin between the layers during the subsequent vacuum resin infusion. The material type of the flow guide fabric is glass fiber, and the grammage is 200g / m2;

[0053] S5, auxiliary material laying of release cloth, release film and vacuum bag is performed on the well-laid main beam material, the vacuum bag is pressed down, the epoxy resin infusion is completed, the mold temperature is increased to 80°C, and curing is performed for 5h, the curing molding is completed, and a wind power blade prefabricated metal main beam is obtained.

[0054] Example 2

[0055] The embodiment provides a wind power blade main beam prefabrication molding method, including the following steps:

[0056] S1, selecting 304 stainless steel metal sheet material, processing into a length of 110m, a width of 0.6m, and a thickness of 0.8mm according to the laying design requirements;

[0057] S2, referring to Figure 1 As shown, the two ends 2 of the metal sheet 1 in the length direction are subjected to inclined cutting machining treatment, and the chamfer is 1:100. The chamfer edge is polished smooth with sandpaper. Referring to Figure 2 As shown, the metal sheet 1 is subjected to round hole 3 processing, the hole diameter is 2mm, and the hole distance is 30mm;

[0058] S3, phosphating surface treatment is performed on the metal sheet. First, the metal sheet is polished with 800# sandpaper, then the surface of the metal sheet is adjusted at room temperature and immersed in a zinc-based phosphating solution, taken out after soaking for 20min, washed with deionized water, and dried with hot air at 60°C;

[0059] S4, the treated metal sheet is laid on the blade main beam prefabrication mold according to the laying design requirements, and all metal sheet 1 materials are used. A layer of flow guide fabric is added between the metal sheets in the upper and lower layers, so as to facilitate the smooth flow of the resin between the layers during the subsequent vacuum resin infusion. The material type of the flow guide fabric is glass fiber, and the grammage is 200g / m2;

[0060] S5, auxiliary material laying of release cloth, release film and vacuum bag is performed on the well-laid main beam material, the vacuum bag is pressed down, the epoxy resin infusion is completed, the mold temperature is increased to 80°C, and curing is performed for 5h, the curing molding is completed, and a wind power blade prefabricated metal main beam is obtained.

[0061] Example 3

[0062] The present embodiment provides a wind turbine blade girder prefabrication forming method, comprising the following steps:

[0063] S1, select 2024 aluminum alloy metal sheet material, according to the requirements of the layer design into length 120m, width 0.5m, thickness 1.0mm;

[0064] S2, referring to Figure 1 , the two ends 2 of the metal sheet 1 in the length direction are processed by beveling machine, the chamfer angle is 1:120, and the chamfer edge is polished round by sandpaper; referring to Figure 2 , the metal sheet 1 is processed by round hole 3, the hole diameter is 2.5mm, and the hole distance is 25mm;

[0065] S3, the metal sheet 1 is treated by silane coupling agent. Ethanol is added in deionized water and stirred uniformly, 1.0% of KH550 silane coupling agent is added in the solution, and the PH value is adjusted to 8-10 by 10% nitrous acid solution to obtain the coupling agent solution. The metal surface is polished by 800# sandpaper, the oil is removed by acetone, then the sample is soaked in the coupling agent solution at room temperature for 20min, taken out and dried in the oven at 220℃ for 50min to obtain the silane film on the metal surface;

[0066] S4, the treated metal sheet 1 is laid on the blade girder prefabrication mold according to the requirements of the layer design together with the glass fiber pultrusion plate 4. The pultrusion plate single piece width is 100mm, the thickness is 5.0mm, 5 pultrusion plates 4 are laid on each layer of the girder, the splicing mode is adopted, and the total width is kept the same as the metal sheet. Referring to Figures 5-6 , the metal sheet 1 and the pultrusion plate 4 are arranged in the upper and lower forms in the thickness direction of the girder, the metal sheet 1 is on the top, and the pultrusion plate 4 is on the bottom. The two ends of the pultrusion plate in the length direction are also processed by beveling machine, and the chamfer size is consistent with the metal sheet. The volume ratio of the metal sheet to the pultrusion plate is 100:100. A layer of flow guide fabric is added between the metal sheet and the metal sheet, between the metal sheet and the pultrusion plate, and between the pultrusion plates of the upper and lower layers, so that the resin can flow smoothly between the layers during the subsequent vacuum resin pouring. The material type of the flow guide fabric is glass fiber, and the grammage is 200g / m2;

[0067] S5, the release cloth, isolation film and vacuum bag auxiliary materials are laid on the well-laid girder material, the vacuum bag is pressed down, the polyurethane resin is poured, the mold temperature is raised to 80℃, and the curing is completed for 5h, the curing forming is completed, and the wind turbine blade prefabricated metal girder is obtained.

[0068] Example 4

[0069] This embodiment provides a method for prefabricating the main beam of a wind turbine blade, including the following steps:

[0070] S1. Select 201 stainless steel sheet material and process it into a length of 110m, a width of 0.6m, and a thickness of 0.4mm according to the layup design requirements;

[0071] S2. Bevel both ends of the metal sheet along its length, with a chamfer of 1:120. Smooth the chamfered edges with sandpaper. Drill round holes in the metal sheet with a diameter of 1.5mm and a spacing of 20mm.

[0072] S3. Sandblasting is performed on the thin metal sheet. This is done on a sandblasting machine using diamond abrasive, with a particle size of 120 mesh, an average particle size of 0.5 mm, a compressed air pressure of 0.7 MPa, a blasting distance of 100 mm, and a blasting angle of 80°.

[0073] S4. The processed metal sheets, along with the carbon fiber pultruded sheets, are laid onto the blade main beam precast mold according to the layup design requirements. Each pultruded sheet is 120mm wide and 1.2mm thick. Five pultruded sheets are laid per layer on the main beam, using a splicing method, maintaining the same overall width as the metal sheets. See [link / reference]. Figures 7-8 As shown, in the thickness direction of the main beam, the metal sheet 1 and the pultruded plate 4 are arranged in an increasing order, from top to bottom: one layer of metal sheet 1, one layer of pultruded plate 4, two layers of metal sheet 1, two layers of pultruded plate 4, three layers of metal sheet 1, and three layers of pultruded plate 4. Each time, one layer of metal sheet 1 and one layer of pultruded plate 4 are added simultaneously until the structural design thickness requirement is met. Both ends of the pultruded plate 4 in the length direction are also beveled, with the chamfer size consistent with that of the metal sheet. The volume ratio of metal sheet 1 to pultruded plate 4 is 100:300. A layer of flow-guiding fabric is added between the upper and lower layers of metal sheets, between the metal sheet and the pultruded plate, and between the pultruded plates to facilitate the smooth flow of resin between layers during subsequent vacuum resin infusion. The material of the flow-guiding fabric is glass fiber with a basis weight of 200 g / m².

[0074] S5. Lay out the release cloth, release film and vacuum bag auxiliary materials on the laid main beam material. Under the pressure of the vacuum bag, complete the injection of epoxy resin. Raise the mold temperature to 80℃ and cure for 5 hours to complete the curing and molding, and obtain the prefabricated metal main beam of wind turbine blade.

[0075] Example 5

[0076] This embodiment provides a method for prefabricating the main beam of a wind turbine blade, including the following steps:

[0077] S1. Select 304 stainless steel sheet material and process it into a length of 110m, a width of 0.6m, and a thickness of 0.8mm according to the layup design requirements;

[0078] S2. The two ends 2 of the metal sheet 1 along the length direction are beveled and chamfered at 1:100. The chamfered edges are smoothed with sandpaper. The metal sheet 1 is then drilled with round holes 3 with a diameter of 2mm and a hole spacing of 30mm.

[0079] S3. The perforated metal sheet 1, according to the layup design requirements, is laid together with the carbon fiber pultruded plate 4 on the precast mold of the blade main beam. Each pultruded plate is 120mm wide and 4.8mm thick. Five pultruded plates 4 are laid in each layer on the main beam, using a splicing method, maintaining the same width as the metal sheet 1 overall. (See also...) Figures 3-4 As shown, in the thickness direction of the main beam, metal sheets 1 and pultruded plates 4 are arranged alternately, with a pultruded plate 4 placed between every two layers of metal sheets 1. Both ends of the pultruded plate 4 in the length direction are also beveled, with the chamfer size consistent with that of the metal sheets. The volume ratio of metal sheets 1 to pultruded plates 4 is 100:300. A layer of flow-guiding fabric is added between the upper and lower layers of metal sheets, and between the metal sheets and the pultruded plates, to facilitate smooth resin flow between layers during subsequent vacuum resin infusion. The flow-guiding fabric is made of glass fiber with a basis weight of 200 g / m².

[0080] S4. Lay out the release cloth, release film and vacuum bag auxiliary materials on the laid main beam material. Under the pressure of the vacuum bag, complete the injection of epoxy resin. Raise the mold temperature to 80℃ and cure for 5 hours to complete the curing and molding, and obtain the prefabricated metal main beam of wind turbine blade.

[0081] Example 6

[0082] This embodiment provides a method for prefabricating the main beam of a wind turbine blade, including the following steps:

[0083] S1. According to the layup design requirements, carbon fiber pultruded sheets are laid on the precast mold of the blade main beam. Each pultruded sheet is 120mm wide and 4.8mm thick. Five pultruded sheets are laid on each layer of the main beam, using a splicing method. The thickness of the carbon fiber pultruded sheet main beam is consistent with the main beam thickness in Example 1. The two ends of the pultruded sheet along its length are beveled with a 1:100 chamfer, and the chamfered edges are sanded smooth. A layer of flow-guiding fabric is added between the upper and lower layers of pultruded sheets to facilitate resin flow during subsequent vacuum infusion. The flow-guiding fabric is made of glass fiber with a basis weight of 200g / m².

[0084] S2, auxiliary material laying of release cloth, isolation film and vacuum bag is carried out on the well-laid main beam material, the epoxy resin is injected under vacuum bag pressure, the mold temperature is raised to 80°C, and curing is carried out for 5h, the curing molding is completed, and the wind power blade prefabricated metal main beam is obtained.

[0085] Example 7

[0086] The present embodiment provides a wind power blade main beam prefabrication molding method, comprising the following steps:

[0087] S1, according to the requirements of the layer design, the glass fiber pultrusion plate is laid on the blade main beam prefabrication mold. The width of the pultrusion plate is 120mm, and the thickness is 4.8mm. Five pultrusion plates are laid on each layer of the main beam, and the splicing method is used. The thickness of the glass fiber pultrusion plate main beam is consistent with the thickness of the main beam in Example 1. The two ends of the pultrusion plate in the length direction are machined with an inclined cutting, and the chamfer is 1:100. The chamfer edge is polished smooth with sandpaper. A layer of flow guide fabric is added between the upper and lower pultrusion plates to facilitate the smooth flow of resin between the layers during subsequent vacuum resin injection. The material type of the flow guide fabric is glass fiber, and the grammage is 200g / m2;

[0088] S2, auxiliary material laying of release cloth, isolation film and vacuum bag is carried out on the well-laid main beam material, the epoxy resin is injected under vacuum bag pressure, the mold temperature is raised to 80°C, and curing is carried out for 5h, the curing molding is completed, and the wind power blade prefabricated metal main beam is obtained.

[0089] The mixed area of the metal sheet and the pultrusion plate in the main beam formed in the above examples is cut and processed according to the sample size in the test standard, and the mechanical property test is carried out. The 0° tensile test is tested by the method in standard ISO 527-5, the sample size is a non-standard sample, the sample test area length is 180mm, the width is 15mm, and the thickness is 4.8mm. Among them, the sample thickness direction distribution in Example 1 is 1.6mm pultrusion plate+0.8mm pultrusion plate+0.8mm pultrusion plate+1.6mm pultrusion plate, the sample thickness direction distribution in Example 2 is 6 layers of 0.8mm metal sheet, the sample thickness direction distribution in Example 3 is 2.4mm pultrusion plate+2.4mm metal sheet, the sample size appearance in Example 4 is the same as that in Example 1, and the sample in Example 5 and Example 6 is all pultrusion plate material. The interlayer shear test is carried out according to standard ISO 14130, the sample size is 50mm in length, 25mm in width and 5mm in thickness, and the material distribution in the thickness direction is consistent with that of the 0° tensile test sample.

[0090] The test results are shown in Table 1.

[0091] Table 1 Comparison of main beam sample material performance test in examples and comparative examples

[0092]

[0093]

[0094] From the above data, all the metal sheet materials are applied in Example 2, so that the 0° tensile modulus and interlaminar shear performance are better than those of Example 1, and the unit cost of the main beam material shows obvious advantages, but the increase of the average density will bring greater pressure to the weight of the main beam. In Example 1, the comprehensive application of carbon fiber pultruded plate and metal sheet material makes a good balance between cost and weight.

[0095] Compared with Example 4, Example 1 has a slight change in material performance because the volume ratio of metal sheet to pultruded plate material does not change, but the arrangement of the structure changes.

[0096] Compared with Example 5, it can be seen that the interlaminar shear strength is greatly improved due to the surface treatment of the metal sheet material, which greatly increases the interfacial performance between the metal material and the pultruded plate.

[0097] Compared with Example 6, it can be seen that compared with the pure carbon fiber pultruded plate, the 0° tensile modulus and interlaminar shear strength of the main beam material are improved to a certain extent due to the application of the metal sheet material, and the material cost is reduced within a certain range.

[0098] Compared with Example 7, it can be seen that compared with the pure glass fiber pultruded plate, the 0° tensile modulus and interlaminar shear strength of the main beam material are improved within a certain range due to the application of the aluminum alloy metal material, and the cost and weight of the aluminum alloy material and the glass fiber pultruded plate are not much different, which will not bring great influence.

[0099] The above-described examples are only the preferred embodiments of the present application, and do not limit the scope of the present application. Any changes made according to the shape and principle of the present application should be covered within the protection scope of the present application.

Claims

1. A method for prefabricating the main beam of a wind turbine blade, characterized in that, It comprises the following steps: S1, selecting a metal material to process a metal sheet with a predetermined size, comprising the following steps: Selecting a metal material to process a metal sheet with a required size, the size of the metal sheet is processed according to the design requirements of different layers of the main beam, and finally curled into a metal coil with a predetermined length, wherein the length of the metal sheet ranges from 100m to 200m, the width ranges from 0.5m to 2.0m, and the thickness ranges from 0.1mm to 3.0mm; S2, after the two ends of the metal sheet in the length direction are machined with beveling, round hole processing is performed, comprising the following steps: The two ends of the metal sheet in the length direction are machined with beveling, and the chamfering range is 1:50-1:200, and the chamfering edge is polished smooth with sandpaper; The metal sheet is processed with round holes, wherein the round holes are spaced at the same distance, the round hole diameter ranges from 1mm to 3mm, and the round hole pitch ranges from 20mm to 40mm; S3, the metal sheet after round hole processing is surface treated to enhance the interfacial bonding strength between it and the resin; S4, the metal sheet after surface treatment is laid on the blade main beam preform mold according to the design requirements of the layer, comprising the following steps: The treated metal sheet is laid on the wind power blade main beam preform mold together with the pultruded plate according to the design requirements of the layer; wherein the width of the pultruded plate ranges from 60mm to 180mm, the thickness ranges from 3mm to 6mm, and the pultruded plate is one or more of glass fiber pultruded plate, carbon fiber pultruded plate and carbon glass hybrid pultruded plate; In the thickness direction of the main beam, the metal sheet and the pultruded plate are laid according to the pre-designed arrangement requirements, wherein the arrangement requirements include the following three kinds: 1) the metal sheet and the pultruded plate are arranged alternately, that is, one layer of pultruded plate is placed between every two layers of metal sheet; 2) all metal sheets are above all pultruded plates, forming an up-down arrangement with the pultruded plates; 3) the metal sheet and the pultruded plate are arranged in an increasing or decreasing manner; If the main beam material of the same layer is a metal sheet, it only contains one metal sheet in the width direction; if the main beam material of the same layer is a pultruded plate, it can contain multiple pultruded plates in the width direction, and the pultruded plates are spliced; the two ends of the pultruded plate in the length direction are also machined with beveling, and the chamfering size is consistent with that of the metal sheet; The volume ratio of the metal sheet to the pultrusion plate is 100:100-100:500, and a flow guide fabric is added between different upper and lower layers to facilitate the smooth flow of resin between layers during subsequent vacuum infusion of resin. The material type of the flow guide fabric is glass fiber, and the grammage of the flow guide fabric ranges from 100g / m 2 -400g / m 2 ; S5, auxiliary material laying of release cloth, release film and vacuum bag is performed on the laid main beam material, resin pouring is completed under vacuum bag pressure, the mold temperature is raised to a predetermined temperature, and curing is performed for a predetermined time to complete curing forming, and a wind power blade preform metal main beam is obtained.

2. A method of preforming a wind turbine blade spar according to claim 1, wherein: The metal material is one or more of stainless steel, aluminum alloy and titanium alloy.

3. A method of preforming a wind turbine blade spar according to claim 1, wherein, The step S3 comprises the following steps: The metal sheet is surface treated to enhance the interfacial bonding strength between it and the resin, wherein the surface treatment method selects one or more of sandpaper polishing, sandblasting, acid pickling, phosphating, flame treatment and silane coupling agent treatment methods: Sandpaper polishing: sandpaper fineness selection 36#-150#, the positive and negative surface of the metal sheet is polished twice, so as to increase the roughness of the metal sheet surface, increase the contact area of the resin and the metal sheet, and then increase the interfacial bonding force; Sand blasting treatment: carried out on a sand blasting machine, the sand blasting selects one of the diamond sand, quartz sand and iron sand, the sand blasting particle size is 50-200 mesh, the average particle size is 0.2-0.8 mm, the compressed air pressure during sand blasting is 0.6-0.85 MPa, the sand blasting distance is 80-120 mm, and the sand blasting angle is 70-85°; under the impact of high-speed sand particles, the substrate of the metal sheet is deformed, the crystal is slipped, the metal surface forms irregular pits without fixed orientation, and the anisotropic surface formed increases the contact area; Pickling treatment: first polish the metal sheet with 800# sandpaper, then remove oil with acetone, then immerse the metal sheet in an 18% hydrochloric acid solution at room temperature, soak for 10-30 min, then take out, rinse with deionized water, and blow dry with hot air at 60°C; Phosphating treatment: first polish the metal sheet with 800# sandpaper, then immerse the metal sheet surface in a zinc-based phosphating solution at room temperature, soak for 10-30 min, then take out, rinse with deionized water, and blow dry with hot air at 60°C; Flame treatment: aim the flame spray gun at the metal sheet surface, distance 20-30 cm, move the gun evenly and slowly, so that the surface temperature of the metal sheet reaches 900-1000°C instantaneously, a layer of metal oxide film is formed on the surface, and a polar functional group is generated, which is beneficial to improve the interfacial bonding force between the metal and the resin; Silane coupling agent treatment: add ethanol to deionized water and stir evenly, add 0.5-2.0% KH550 silane coupling agent solution by mass fraction, and adjust the PH to 8-10 with 10% nitrous acid solution to obtain a coupling agent solution; first polish the metal sheet surface with 800# sandpaper, remove oil with acetone, then immerse the sample in the coupling agent solution at room temperature for 10-30 min, take it out, and dry it in an oven at 200-250°C for 30-60 min to obtain a silane film on the metal surface.

4. A method of preforming a wind turbine blade spar according to claim 1, wherein, The step S5 includes the following steps: The release cloth, isolation film and vacuum bag auxiliary materials are laid on the laid main beam material, the vacuum bag is pressed down, the resin is poured, the mold temperature is raised to 70-90°C, and the curing is completed for 4-10 h to complete the curing molding to obtain the wind power blade prefabricated metal main beam, wherein the pouring resin is one of epoxy resin, unsaturated polyester resin, polyurethane resin and vinyl resin.

Images