A kind of pultrusion plate girder interlayer perfusion structure and perfusion method of wind power blade

Abstract

The present application relates to the technical field of wind power blade processing, and specifically provides a pultrusion plate main beam interlayer pouring structure of a wind power blade, which comprises a lower flow guide arranged on the lower surface of the pultrusion plate main beam and an upper flow guide arranged on the upper surface of the pultrusion plate main beam, and the two sides of the lower flow guide extend to the lower ends of the side cores on the two sides of the pultrusion plate main beam; the pouring side of the pultrusion plate main beam is provided with a pouring pipe in communication with the upper flow guide, and an air extraction assembly is arranged between the upper flow guide and the air extraction side core of the pultrusion plate main beam. The present application also provides a pultrusion plate main beam interlayer pouring method of a wind power blade, which can reduce pouring defects between pultrusion plates and enhance the pouring quality and uniformity of the joint of pultrusion plates by making resin penetrate from the upper surface, the lower surface and the side of the pultrusion plate main beam.

Description

Technical Field

[0001] This invention relates to the field of wind turbine blade processing technology, and in particular to an interlayer grouting structure and grouting method for the pultruded main beam of a wind turbine blade. Background Technology

[0002] Wind energy, as a green and environmentally friendly renewable energy source, has been increasingly widely used. Wind power generation is of great significance to many regions, especially coastal islands, grassland pastoral areas, mountainous areas, and plateau regions that lack water, fuel, or have inconvenient transportation. As the most basic and critical component of a wind turbine generator set, the performance and quality of the wind turbine blades are the decisive factors in ensuring the normal operation of the wind turbine generator set.

[0003] To improve the overall quality and performance of wind turbine blades, blade materials are required to possess higher mechanical properties, superior quality, faster operating efficiency, and lower costs, leading to a gradual shift towards larger sizes and lighter weights in wind turbine blades. Traditional wind turbine blade spars are mostly formed using fiberglass or carbon fiber fabrics through lay-up and injection molding processes. Blade spars produced using this method suffer from drawbacks such as low mechanical properties, numerous injection defects, poor wetting, uneven resin distribution, and low molding efficiency. Pultruded sheets, on the other hand, offer advantages such as high fiber content and stable composite quality. Using lighter pultruded sheets for wind turbine blade spars, while meeting stiffness and strength requirements, can effectively reduce the overall weight of the blade. During the fabrication of pultruded sheet main spars, multiple pultruded sheets are stacked, and then resin is injected into the gaps between adjacent pultruded sheets. Existing technologies include the following patents related to the injection of pultruded sheets:

[0004] 1. The invention patent with patent number "201910114787.7" and patent name "A pultruded part for wind turbine blades, a method for infusion of wind turbine blades and wind turbine blades" has a prism-shaped pultruded part with a parallelogram-shaped cross section in the thickness direction. The infusion method in this invention can enhance the strength of the through joint, reduce the risk of resin back-wrapping in the pultruded part, and improve the overall strength and infusion effect of the main beam.

[0005] 2. The invention patent application with patent number "202210811321.4" and patent name "composite material pultruded sheet and wind turbine blade beam material structure" can significantly improve the resin injection speed by setting two flow guide grooves on each of the two outer walls of the composite material pultruded sheet, which can effectively solve the problem of slow resin penetration in existing composite material pultruded sheets.

[0006] 3. The invention patent application with patent number "201910159604.3" and patent name "A Pultruded Reinforced Sheet for Wind Turbine Blades that Facilitates Resin Flow and Its Manufacturing Method" includes multiple layers of stacked pultruded sheets, with resin injected between each layer of pultruded sheets. Several flow grooves are provided on the side of the pultruded sheets along the length direction, and the flow grooves penetrate the pultruded sheets along the thickness direction. This invention can automatically balance the amount of resin between each layer, reduce the risk of excessive or insufficient resin between layers, improve the uniformity of resin injection, improve the interlayer bonding strength of the blade sheet, and improve the mechanical properties of the blade.

[0007] The aforementioned comparative documents can improve the infusion performance of interlayer resin in pultruded plates to some extent. However, these documents primarily focus on adjusting the interlayer structure of the pultruded plates, offering limited improvement in infusion performance. They do not address the flow of other auxiliary resins used in conjunction with the pultruded plates, or structures and methods for improving interlayer infusion efficiency and uniformity. Therefore, designing an infusion structure and method for the interlayer infusion of pultruded plate main beams in wind turbine blades that can significantly reduce infusion defects between pultruded plates, enhance the infusion quality of pultruded plate joints, and reduce the risk of backflow in pultruded plate joints is a pressing issue that needs to be addressed. Summary of the Invention

[0008] To address the aforementioned problems, this invention provides an interlayer grouting structure and method for pultruded main beams of wind turbine blades. Through the cooperation of upper guide members, lower guide members, injection pipes, cores, and extraction components, the interlayer grouting uniformity of the pultruded main beam can be enhanced, the grouting quality of the pultruded main beam joints can be improved, and the risk of back-wrapping of the pultruded main beam joints can be reduced, effectively solving the grouting defects between the layers of the pultruded main beam.

[0009] To achieve the above objectives, the present invention proposes the following technical solution: an interlayer injection structure and injection method for a pultruded main beam of a wind turbine blade, wherein the pultruded main beam is composed of multiple stacked pultruded plates, and a core is provided on the side of the pultruded main beam. The injection structure includes a lower guide member laid on the lower surface of the pultruded main beam and an upper guide member laid on the upper surface of the pultruded main beam. The lower guide member extends to the lower end of the core on both sides. The two sides of the pultruded main beam are respectively the injection side and the extraction side. The injection side is provided with an injection pipe communicating with the upper guide member. The upper guide member extends from the upper end of the core on the injection side to the extraction side and leaves a closed gap area between it and the end face of the pultruded main beam on the extraction side. An extraction assembly located above the closed gap area is provided between the core on the extraction side and the upper guide member.

[0010] Preferably, the upper guide member includes a guide net that extends from the upper end face of the injection side core to the upper surface of the pultruded plate main beam, and the inner end of the guide net is located below the inner end of the air extraction assembly.

[0011] Preferably, the injection pipe includes an inlet pipe located above the injection side core and a distribution pipe connected to the inlet pipe, with the guide net connected to the distribution pipe.

[0012] Preferably, the feed pipe includes a main feed pipe arranged parallel to the feed distribution pipe, and multiple feed branch pipes are vertically connected between the main feed pipe and the feed distribution pipe; the feed distribution pipe is an ohmic tube with a semi-circular structure.

[0013] Preferably, a flow-blocking band parallel to the flow-blocking pipe is provided on the inner side of the flow guide net, and the flow-blocking band is located above the filling side core.

[0014] Preferably, the air extraction assembly includes an air extraction bag whose inner end overlaps with the guide net; a processing mold is provided on the outside of the pultruded plate main beam, and an air extraction port is included on the mold flange side of the air extraction side. The air extraction bag is connected to the air extraction port through multiple air outlets to extract the air from the pultruded plate joint.

[0015] Preferably, the lower guide is a continuous felt made of composite glass fiber, with both sides of the continuous felt extending below the injection side core and the extraction side core, and the extension length H1 is 20mm-50mm.

[0016] Preferably, the width H2 of the closed interval is 50mm-90mm; the overlap width H3 at the junction of the inner end of the suction bag and the inner end of the guide net is 8-12mm; and the outer end of the suction bag is located at the edge of the end face of the pultruded plate main beam on the suction side.

[0017] A method for interlayer grouting of pultruded main beams for wind turbine blades, employing the aforementioned grouting structure, involves simultaneously impregnating the pultruded main beam with resin from both the upper and lower surfaces via bidirectional feeding. The method specifically includes the following steps:

[0018] S1: Add resin to the main feed pipe, and the resin flows into the distribution pipe through the feed branch pipe;

[0019] S2: Some resin flows from the feed pipe into the injection side sandwich and is guided by the lower guide to the lower surface of the pultruded plate main beam; some resin flows through the flow-blocking strip and is blocked by the flow-blocking strip before entering the guide net above the pultruded plate main beam for diffusion.

[0020] S3, under negative pressure, the resin on the upper and lower surfaces of the pultruded main beam penetrates into the pultruded main beam;

[0021] S4: During the process of resin permeating into the pultruded main beam, the air extraction bag extracts air from the closed interval area into the pultruded main beam until the resin closes, and the injection is completed.

[0022] Preferably, the lower guide member guides the resin to the pultruded main beam while simultaneously guiding the resin to the suction side core; the resin in the suction side core and the injection side core is laterally immersed into the pultruded main beam, and combined with the resin immersion on the upper and lower surfaces of the pultruded main beam, the pultruded main beam is circumferentially fed.

[0023] The beneficial effects of this invention are:

[0024] 1. The present invention includes a flow guide net, a vacuum bag, and a continuous felt. The flow guide net can guide the resin impregnation on the upper surface of the pultruded main beam, and the continuous felt can guide the resin impregnation on the lower surface of the pultruded main beam, so that the upper and lower surfaces of the pultruded main beam can be fed simultaneously in both directions, thereby improving the uniformity of resin injection in the joints of the pultruded main beam and improving the injection quality.

[0025] 2. The present invention includes an air extraction component, wherein the air extraction bag overlaps the upper end of the inner end of the guide net, and can extract the air in the splice of the pultruded plate main beam from the closed gap area between the guide net and the air extraction side core, so as to avoid the air remaining in the splice forming air bubbles and causing injection defects, and can further improve the injection quality of resin.

[0026] 3. The injection pipe in this invention includes a main feed pipe and an injection branch pipe connected to the distribution pipe. The distribution pipe is a semi-circular ohmic tube. Through the cooperation of the main feed pipe, the injection branch pipe and the ohmic tube, the flow rate of the resin can be improved, the resin can be better guided, and the injection efficiency and injection uniformity of the pultruded plate main beam can be improved.

[0027] 4. The present invention has a flow-blocking band on the inner side of the ohmic tube on the flow guide net, which can to a certain extent prevent the resin flow rate at the beginning of the flow guide net on the injection side, avoid a large amount of resin flowing into the middle of the pultruded plate main beam, ensure the resin immersion amount at the beginning of the pultruded plate main beam on the injection side, and improve the uniformity of injection. Attached Figure Description

[0028] Figure 1 This is a front view schematic diagram of the grouting structure (the main feed pipe and feed branch pipe are not shown).

[0029] Figure 2 yes Figure 1 A top-down view.

[0030] Figure 3 This is a diagram showing the resin injection process in the splice of the pultruded plate main beam (the main feed pipe and feed branch pipe are not shown).

[0031] Figure 4 This is a schematic diagram of an ohm tube.

[0032] Figure label:

[0033] 1. Pultruded plate main beam; 2. Evacuation bag; 3. Flow guide net; 4. Flow barrier; 5. Material distribution pipe; 6. Injection side sandwich; 7. Continuous felt; 8. Main feed pipe; 9. Evacuation port; 10. Mold flange edge; 11. Evacuation side sandwich; 12. Closed interval area; 13. Feed branch pipe; 15. Air outlet; 16. Joint. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this invention clearer, the following description is provided in conjunction with the appendix. Figure 1-4 The present invention will be further described in detail below with reference to specific embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and do not constitute a limitation thereof.

[0035] An interlayer injection molding structure for a pultruded plate main beam of a wind turbine blade, wherein the pultruded plate main beam 1 is composed of multiple stacked pultruded plates, and a core is provided on the side of the pultruded plate main beam 1, forming a joint 16 between adjacent pultruded plates. Figure 1 As shown, the injection structure includes a lower guide member laid on the lower surface of the pultruded main beam 1 and an upper guide member laid on the upper surface of the pultruded main beam 1. The upper guide member includes a guide net 3, and the lower guide member is a continuous felt 7 made of composite glass fiber material; the two sides of the pultruded main beam 1 are respectively Figure 1-3 As shown at point A on the injection side and point B on the extraction side, the guide net 3 extends from the upper end face of the injection side core 6 to the upper surface of the pultruded plate main beam 1. The two sides of the lower guide extend to the lower end of the core. Specifically, the two sides of the continuous felt 7 extend to the lower part of the injection side core 6 and the extraction side core 11 respectively, and the extension length H1 is 20mm-50mm, preferably 30mm, 35mm or 40mm, to ensure that the resin on the continuous felt 7 flows into the injection side core 6 and the extraction side core 11.

[0036] like Figure 1 and Figure 2 As shown, the injection side is provided with an injection pipe connected to the guide net 3. The injection pipe includes an inlet pipe located above the injection side core 6 and a distribution pipe 5 connected to the inlet pipe. The guide net 3 is connected to the distribution pipe 5. The inlet pipe includes a main inlet pipe 8 arranged parallel to the distribution pipe 5. Multiple inlet branch pipes 13 are vertically connected between the main inlet pipe 8 and the distribution pipe 5. The distribution pipe 5 is an ohmic tube with a semi-circular structure.

[0037] like Figure 2 As shown, a flow-blocking band 4 parallel to the distribution pipe 5 is provided on the inner side of the flow guide net 3. In this embodiment, the flow-blocking band 4 is a sealing tape. The flow-blocking band 4 is located above the injection-side core 6. The distribution pipe 5 above the injection-side core 6 is the injection starting point of the pultruded plate main beam 1, that is... Figure 3The resin injection area shown at point M; because the resin flowing out of the ohmic tube has a relatively fast flow rate on the guide net 3, if there is no flow-blocking effect of the flow-blocking band 4, the resin will quickly diffuse towards the center with the guide net 3, resulting in too little resin injected at the joint 16 at the beginning of the injection side, causing uneven injection. The ohmic tube can control the flow rate of the resin at the beginning of the injection side of the guide net 3, avoiding a large amount of resin flowing into the center of the pultruded main beam 1 and not being able to flow evenly into the injection side of the pultruded main beam 1, thus ensuring the amount of resin impregnated at the beginning of the injection side of the pultruded main beam 1 and improving the uniformity of injection.

[0038] like Figure 1 As shown, the guide net 3 extends from the upper end of the core 6 on the injection side to the extraction side, and a closed gap area 12 is left between it and the end face of the pultruded main beam 1 on the extraction side. The resin is injected into the... Figure 3 The area shown at point N is closed; the width H2 of the closed interval 12 is 50mm-90mm, preferably 60mm, 70mm or 80mm, which can meet both the injection efficiency and the drainage time and injection sufficiency of the joint 16 in the middle of the pultruded plate main beam 1; since most of the resin is guided to the pultruded plate main beam 1 through the guide net 3, if the width of the closed interval 12 is too wide, the width of the guide net 3 will become narrower, which will prolong the injection time of the joint 16 and affect the performance of other components; if the width of the closed interval 12 is too narrow, the width of the guide net 3 will become longer, so the joint 16 only needs a very short injection time to be filled, which will result in insufficient injection in the joint 16 in the middle of the pultruded plate main beam 1, thus affecting the injection uniformity and injection quality.

[0039] like Figure 2 As shown, an air extraction assembly is provided between the air extraction side sandwich core 11 and the guide net 3, located above the closed interval area 12. The inner end of the guide net 3 is located below the inner end of the air extraction assembly. The air extraction assembly includes an air extraction bag 2 whose inner end overlaps with the guide net 3. The outer end of the air extraction bag 2 is located at the edge of the end face of the pultruded plate main beam 1 on the air extraction side. The overlap width H3 at the overlap between the inner end of the air extraction bag 2 and the inner end of the guide net 3 is 8-12mm, preferably 10mm, which can improve the air extraction efficiency and performance of the air extraction bag 2. A processing mold is provided on the outside of the pultruded plate main beam 1, such as... Figure 2 As shown, the mold flange edge 10 on the extraction side includes an extraction port 9. The extraction bag 2 is connected to the extraction port 9 through a multi-way air outlet 15 to extract the air from the pultruded plate joint 16, so as to avoid the air remaining in the joint 16 forming air bubbles and causing injection defects, thereby further improving the injection quality of the joint 16 in the pultruded plate main beam 1.

[0040] A method for interlayer grouting of pultruded main beams for wind turbine blades, employing the aforementioned grouting structure, involves simultaneously impregnating the pultruded main beam 1 with resin from both the upper and lower surfaces via bidirectional feeding. The method specifically includes the following steps:

[0041] S1: Add resin to the main feed pipe 8, and the resin flows into the distribution pipe 5 through the feed branch pipe 13;

[0042] S2: Some resin flows from the feed pipe 5 into the injection side sandwich 6 and is guided by the continuous felt 7 to the lower surface of the pultruded plate main beam 1; some resin flows through the flow-blocking band 4 and is blocked by the flow-blocking band 4 before entering the flow-guiding net 3 above the pultruded plate main beam 1 for diffusion.

[0043] S3, under the action of negative pressure, the resin on the upper surface and the lower surface of the pultruded main beam 1 penetrates into the pultruded main beam 1;

[0044] S4: During the process of resin permeating into the pultruded main beam 1, the air extraction bag 2 extracts air from the closed interval area 12 into the pultruded main beam 1 until the resin injection closes at point N, and the injection is completed.

[0045] It is worth noting that while the continuous felt 7 guides the resin to the pultruded main beam 1, it also guides the resin to the suction side core 11. The resin in the suction side core 11 and the injection side core 6 will laterally immerse into the pultruded main beam 1. Combined with the resin immersion on the upper and lower surfaces of the pultruded main beam 1, the pultruded main beam is fed circumferentially. This can maximize the interlayer injection uniformity of the pultruded main beam 1, enhance the injection quality of the joints 16 in the pultruded main beam 1, reduce the risk of back-wrapping of the joints 16, and effectively solve the injection defects between the layers of the pultruded main beam 1.

[0046] Although embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

[0047] The specific embodiments of the present invention described above do not constitute a limitation on the scope of protection of the present invention. Any other corresponding changes and modifications made in accordance with the technical concept of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A method for interlayer grouting of pultruded plate main beams for wind turbine blades, characterized in that, The pultruded main beam (1) is composed of multiple stacked pultruded plates. The side of the pultruded main beam (1) is provided with a core. The injection structure includes a lower guide laid on the lower surface of the pultruded main beam (1) and an upper guide laid on the upper surface of the pultruded main beam (1). The lower guide extends to the lower end of the core on both sides. The two sides of the pultruded main beam (1) are the injection side and the extraction side, respectively. The injection side is provided with an injection pipe that communicates with the upper guide. The upper guide extends from the upper end of the injection side core (6) to the extraction side and leaves a closed gap area (12) between it and the end face of the extraction side pultruded main beam (1). The extraction side core (11) and the upper guide An air extraction assembly is provided between the components above the closed interval area (12); the upper guide component includes a guide net (3), the injection pipe includes an inlet pipe located above the filling side core (6) and a distribution pipe (5) connected to the inlet pipe, the guide net (3) is connected to the distribution pipe (5); the inlet pipe includes an inlet main pipe (8) arranged parallel to the distribution pipe (5), the guide net (3) has a flow-blocking band (4) parallel to the distribution pipe (5) on the inner side of the distribution pipe (5), the flow-blocking band (4) is located above the filling side core (6); the air extraction assembly includes an air extraction bag (2) whose inner end overlaps the guide net (3); Resin is simultaneously impregnated into the pultruded main beam (1) from both the upper and lower surfaces using a bidirectional feeding method, specifically including the following steps: S1: Add resin to the main feed pipe (8), and the resin flows into the distribution pipe (5) through the feed branch pipe (13); S2: Some resin flows from the feed pipe (5) into the filling side sandwich (6) and is guided by the lower guide to the lower surface of the pultruded plate main beam (1); some resin flows through the flow-blocking strip (4) and is blocked by the flow-blocking strip (4) before entering the flow-guiding net (3) above the pultruded plate main beam (1) for diffusion. S3, under the action of negative pressure, the resin on the upper surface and the lower surface of the pultruded main beam (1) penetrates into the pultruded main beam (1); S4: During the process of resin permeating into the pultruded main beam (1), the air extraction bag (2) extracts air from the closed interval area (12) into the pultruded main beam (1) until the resin closes, and the injection is completed; The lower guide component guides the resin to the pultruded main beam (1) and simultaneously guides the resin to the suction side sandwich (11); the resin in the suction side sandwich (11) and the injection side sandwich (6) is laterally immersed into the pultruded main beam (1), and the resin immersion on the upper surface and lower surface of the pultruded main beam (1) is combined to perform circumferential feeding of the pultruded main beam.

2. The interlayer grouting method for the pultruded main beam of wind turbine blades according to claim 1, characterized in that, The guide net (3) extends from the upper end face of the injection side sandwich (6) to the upper surface of the pultruded plate main beam (1), and the inner end of the guide net (3) is located below the inner end of the air extraction assembly.

3. The interlayer grouting method for the pultruded main beam of wind turbine blades according to claim 2, characterized in that, The main feed pipe (8) and the distribution pipe (5) are vertically connected by multiple feed branch pipes (13); the distribution pipe (5) is an ohmic tube with a semi-circular structure.

4. The interlayer grouting method for the pultruded main beam of wind turbine blades according to claim 3, characterized in that, The pultruded plate main beam (1) is provided with a processing mold. The mold flange edge (10) on the air extraction side includes an air extraction port (9). The air extraction bag (2) is connected to the air extraction port (9) through multiple air outlets (15) to extract the air from the pultruded plate joint (16).

5. The method for interlayer grouting of the pultruded main beam of a wind turbine blade according to any one of claims 1-4, characterized in that, The lower guide is a continuous felt (7) made of composite glass fiber. The continuous felt (7) extends to the bottom of the injection side core (6) and the extraction side core (11) on both sides, and the extension length H1 is 20mm-50mm.

6. The method for interlayer grouting of the pultruded main beam of wind turbine blades according to claim 5, characterized in that, The width H2 of the closed interval area (12) is 50mm-90mm; the overlap width H3 at the junction of the inner end of the suction bag (2) and the inner end of the guide net (3) is 8-12mm; and the outer end of the suction bag (2) is located at the edge of the end face of the pultruded plate main beam (1) on the suction side.

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