Forming die of composite pultrusion plate for wind power blade

Abstract

The invention relates to the technical field of wind power blade pultrusion plate molds, and discloses a forming mold of a composite material pultrusion plate for a wind power blade, the forming mold of the composite material pultrusion plate for the wind power blade comprises a preheating section, a gel section, a curing section and a cooling section, the preheating section, the gel section, the curing section and the cooling section each comprise a mold body, the parts, at the preheating section, the gel section, the curing section and the cooling section, of the mold body are sequentially connected through connecting assemblies, and uniformly distributed heating rods are mounted on the inner sides, at the preheating section, the gel section and the curing section, of the mold body. Through cooperation of the preheating section, the gel section, the curing section and the cooling section, the mold is divided into a plurality of independent heating sections and a single cooling section in the length direction, independent and high-precision heating elements and cooling channels are arranged in each section, and the problems that an existing pultrusion mold is out-of-control in temperature gradient, lagged in dynamic response, waste in energy consumption and low in production efficiency are solved. And the speed is bottleneck.

Description

Technical Field

[0001] The present invention relates to the technical field of pultruded plate molds for wind turbine blades, in particular to a forming mold for pultruded composite material plates for wind turbine blades. Background Art

[0002] As wind turbine blades become larger, pultruded sheets for main beams and webs are developing in the direction of ultra-thickness (>40mm), ultra-width (>150mm), and high performance. Traditional pultrusion dies use integral heating cylinders or single temperature zone control, which have the following inherent defects: Uncontrolled temperature gradient: The temperature difference between the mold inlet and outlet can reach as high as 50°C or more, resulting in insufficient core curing / over-curing of the surface layer in thick-section plates (the measured core-surface curing difference is greater than 15%), causing delamination risk.

[0003] Dynamic response lag: Switching resin systems (e.g., epoxy to polyurethane) requires several hours of downtime to adjust the temperature curve, which cannot adapt to multi-material production needs.

[0004] Energy waste: Overall heating causes non-forming areas (such as cooling sections) to continuously consume energy, accounting for more than 35% of the total power.

[0005] Speed ​​bottleneck: Lack of independent cooling section and demoulding temperature > 80°C force the pulling speed to be limited to below 0.8m / min (for 40mm thick plates).

[0006] To this end, we proposed a modular zoned heating and cooling forming die for composite pultruded sheets for wind turbine blades. Summary of the Invention

[0007] The object of the present invention is to provide a forming die for a composite pultruded plate material for wind turbine blades, so as to solve the problems raised in the background art.

[0008] To achieve the above objectives, the present invention provides the following technical solution: a forming die for a composite pultruded sheet material for wind turbine blades, comprising a preheating section, a gel section, a curing section, and a cooling section, wherein each of the preheating section, the gel section, the curing section, and the cooling section comprises a die body, and the die bodies at the preheating section, the gel section, the curing section, and the cooling section are sequentially connected by a connecting assembly, and uniformly distributed heating rods are installed on the inner sides of the die bodies at the preheating section, the gel section, and the curing section; A water cooling assembly is installed inside the mold body at the cooling section; The mold body includes an upper mold plate, a lower mold plate, a lower mold base, and an upper mold base. The upper mold plate and the lower mold plate are fixedly connected by evenly distributed screws. The upper mold base is installed on the inner side of the upper mold plate, and the lower mold base is installed on the inner side of the lower mold plate. The mold cavity is formed between the lower mold base and the upper mold base.

[0009] Furthermore, the middle portion of the upper mold base is provided with exhaust holes distributed in a triangular array, and the upper mold plate is provided with outlet holes corresponding to the exhaust holes.

[0010] In the triangular array, the distance between any two adjacent vent holes is equal (the sides of the equilateral triangle are of the same length), which ensures that the "path length" of gas from all areas of the mold cavity to the nearest vent hole is basically the same, avoiding the problem of localized gas accumulation and inability to exhaust; Furthermore, evenly distributed heating rods are installed on the inner sides of the upper template and the lower template at the preheating section, the gel section, and the curing section.

[0011] Furthermore, the heads of the lower mold base and the upper mold base in the preheating section are fixedly installed with wear-resistant parts, and the wear-resistant parts include wear-resistant blocks, and the wear-resistant blocks are made of cemented carbide and have introduction grooves. The heads of the lower mold base and the upper mold base are fixedly installed with wear-resistant blocks by screws, and the wear-resistant blocks are provided with evenly distributed introduction grooves.

[0012] Furthermore, the groove depth and groove width of the introduction groove gradually decrease from the preheating section to the gel section.

[0013] When the fiber bundle immersed in resin enters the introduction groove, the groove width and groove depth gradually decrease from the preheating section to the gel section. The groove depth and groove width are larger at the entrance, guiding a large amount of resin to quickly enter and wrap the fiber; along the pultrusion direction, the groove depth and groove width gradually decrease, the transition is gentle, and finally disappear completely, ensuring a steady increase in pressure, promoting fiber infiltration and reducing bubble entrainment. The high wear area of ​​the mold is mainly at the mold inlet where the fiber bundle is introduced. The wear-resistant block is detachable and made of carbide, which makes the mold inlet have high wear resistance and can be easily replaced. Furthermore, the water cooling assembly includes a water channel dummy, copper plugging, and a partition. The inner sides of the upper and lower templates at the cooling section are provided with channels corresponding to the water channel dummy. The side channel openings of the upper and lower templates are threadedly connected with copper plugging. The upper and lower templates are provided with water inlet holes and water outlet holes corresponding to the channels. The channel includes evenly distributed transverse waterways and vertical waterways connecting the transverse waterways, and the transverse waterways at both ends are connected to the water inlet and the water outlet respectively; Except for the transverse water channel connected to the water outlet, all other transverse water channels are equipped with partitions, and the heads of the partitions are provided with arc grooves.

[0014] Control the external water supply equipment to introduce water into the corresponding channel of the water channel prosthesis through the water inlet hole. The water flows through the baffle and continuously circulates in the horizontal water channel and the vertical water channel, and finally flows out from the water outlet hole, thereby realizing water circulation cooling, and then shaping and reducing the mold temperature of the internal solidified plate; Furthermore, a connection assembly is installed between adjacent upper templates and lower templates, and the connection assembly includes a connection block 1, a connection block 2, and an insert block. The connection block 1 and the connection block 2 are fixedly installed with the insert block, and the connection block 2 is engaged with the outer side of the connection block 1 and locked with each other by screws. The upper template and the lower template are provided with grooves corresponding to the insert blocks, and the insert blocks are fixed to the corresponding upper template and lower template by screws; The upper connecting block 2 and the lower connecting block 2 are locked to each other by screws; The connecting block 1 and the connecting block 2 on the upper side and the connecting block 1 and the connecting block 2 on the lower side form a transition cavity corresponding to the mold cavity.

[0015] Furthermore, the mold cavity and the transition cavity are plated with a wear-resistant base layer, which is a hard chromium layer.

[0016] Compared with the prior art, the present invention provides a forming die for composite pultruded sheets for wind turbine blades, which has the following beneficial effects: 1. The present invention divides the mold into multiple independent heating sections and a single cooling section along the length direction through the coordinated effects of the preheating section, gel section, curing section, and cooling section. Each section has built-in independent, high-precision heating elements and cooling channels, which solves the technical defects of existing pultrusion molds such as temperature gradient out of control, dynamic response lag, energy waste, and speed bottlenecks.

[0017] 2. The present invention adopts a detachable design for most of the structures, so that various parts of the mold can be quickly disassembled and replaced. Rapid mold change directly improves the production line speed and equipment utilization rate, and the modular design is suitable for multi-variety production. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention; Figure 2 This is a schematic diagram of the three-dimensional structure of the present invention from another angle; Figure 3 This is a schematic diagram of the exploded three-dimensional structure of the present invention; Figure 4 This is a schematic diagram of the exploded three-dimensional structure of the present invention from another angle; Figure 5 This is a schematic diagram of the exploded three-dimensional structure of the mold body and the heating rod of the present invention; Figure 6 This is a schematic diagram of the exploded three-dimensional structure of the mold body and the heating rod of the present invention from another angle; Figure 7 Schematic diagram of the three-dimensional structure of the lower mold base and the upper mold base of the present invention; Figure 8 Schematic diagram of the three-dimensional structure of the wear-resistant part of the present invention; Figure 9Schematic diagram of the exploded three-dimensional structure of the cooling section of the present invention; Figure 10 This is a schematic diagram of the exploded three-dimensional structure of the cooling section of the present invention from another angle; Figure 11 Schematic diagram of the three-dimensional structure of the connection assembly of the present invention; Figure 12 Schematic diagram of the exploded three-dimensional structure of the connection assembly of the present invention; Figure 13 FIG. 2 is a schematic diagram of the exploded three-dimensional structure of the connection assembly of the present invention from another angle.

[0019] In the figure: 1. Preheating section; 2. Gel section; 3. Curing section; 4. Cooling section; 5. Mold body; 51. Upper template; 52. Lower template; 53. Lower mold base; 54. Upper mold base; 6. Heating rod; 7. Wear-resistant parts; 71. Wear-resistant blocks; 72. Inlet groove; 8. Water cooling assembly; 81. Water channel prosthesis; 82. Copper plug; 83. Partition; 9. Connecting assembly; 91. Connecting block 1; 92. Connecting block 2; 93. Insert block. DETAILED DESCRIPTION

[0020] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention. Example

[0021] See also Figures 1-13 The forming die of the composite pultruded sheet material for wind turbine blades includes a preheating section 1, a gel section 2, a curing section 3, and a cooling section 4. The preheating section 1, the gel section 2, the curing section 3, and the cooling section 4 all include a die body 5. The die bodies 5 at the preheating section 1, the gel section 2, the curing section 3, and the cooling section 4 are sequentially connected by a connecting assembly 9. Evenly distributed heating rods 6 are installed on the inner sides of the die bodies 5 at the preheating section 1, the gel section 2, and the curing section 3. A water cooling assembly 8 is installed inside the mold body 5 at the cooling section 4; The mold body 5 includes an upper mold plate 51, a lower mold plate 52, a lower mold base 53, and an upper mold base 54. The upper mold plate 51 and the lower mold plate 52 are fixedly connected by evenly distributed screws. The upper mold base 54 is installed on the inner side of the upper mold plate 51, and the lower mold base 53 is installed on the inner side of the lower mold plate 52. The mold cavity is formed between the lower mold base 53 and the upper mold base 54.

[0022] Furthermore, a triangular array of exhaust holes is provided in the middle of the upper mold base 54 , and outlet holes corresponding to the exhaust holes are provided on the upper mold plate 51 .

[0023] In the triangular array, the distance between any two adjacent vent holes is equal (the sides of the equilateral triangle are of the same length), which ensures that the "path length" of gas from all areas of the mold cavity to the nearest vent hole is basically the same, avoiding the problem of localized gas accumulation and inability to exhaust; Furthermore, evenly distributed heating rods 6 are installed on the inner sides of the upper template 51 and the lower template 52 at the preheating section 1 , the gel section 2 , and the curing section 3 .

[0024] Furthermore, the heads of the lower mold base 53 and the upper mold base 54 in the preheating section 1 are fixedly installed with wear-resistant parts 7, and the wear-resistant parts 7 include wear-resistant blocks 71, the wear-resistant blocks 71 are made of cemented carbide, and have introduction grooves 72. The heads of the lower mold base 53 and the upper mold base 54 are fixedly installed with wear-resistant blocks 71 by screws, and the wear-resistant blocks 71 are provided with evenly distributed introduction grooves 72.

[0025] Furthermore, the groove depth and groove width of the introduction groove 72 gradually decrease from the preheating section 1 to the gel section 2.

[0026] When the fiber bundle impregnated with resin enters the introduction groove 72, the groove width and groove depth of the introduction groove 72 gradually decrease from the preheating section 1 to the gel section 2. The groove depth and groove width are larger at the entrance, guiding a large amount of resin to quickly enter and wrap the fiber. The groove depth and groove width gradually decrease along the pultrusion direction, with a gentle transition and eventually disappearing completely, ensuring a steady increase in pressure, promoting fiber infiltration and reducing bubble entrainment. The high wear area of ​​the mold is mainly at the mold inlet where the fiber bundle is introduced. The wear-resistant block 71 is detachable and made of carbide, which makes the mold inlet have high wear resistance and can be easily replaced. Furthermore, the water cooling assembly 8 includes a water channel dummy 81, a copper plug 82, and a partition 83. The inner sides of the upper template 51 and the lower template 52 at the cooling section 4 are provided with a channel corresponding to the water channel dummy 81. The side channel openings of the upper template 51 and the lower template 52 are both threadedly connected with the copper plug 82. The upper template 51 and the lower template 52 are provided with water inlet holes and water outlet holes corresponding to the channels. The channel includes evenly distributed horizontal waterways and vertical waterways connecting the horizontal waterways. The horizontal waterways at both ends are connected to the water inlet and the water outlet respectively. Except for the transverse water channel connected to the water outlet, the rest of the transverse water channels are all installed with partitions 83, and the heads of the partitions 83 are provided with arc grooves.

[0027] Control the external water supply device to introduce water into the corresponding channel of the water channel prosthesis 81 through the water inlet hole. The water flows through the partition 83 and continuously circulates in the horizontal water channel and the vertical water channel, and finally flows out from the water outlet hole, thereby realizing water circulation cooling, and then shaping and reducing the mold temperature of the internal solidified plate; Furthermore, a connection assembly 9 is installed between adjacent upper templates 51 and lower templates 52. The connection assembly 9 includes a connection block 1 91, a connection block 2 92, and an insert block 93. The insert block 93 is fixedly installed on the connection block 1 91 and the connection block 2 92. The connection block 2 92 is engaged with the outer side of the connection block 1 91 and locked with each other by screws. The upper templates 51 and the lower templates 52 are provided with grooves corresponding to the insert blocks 93. The insert blocks 93 are fixed to the corresponding upper templates 51 and lower templates 52 by screws. The upper connecting block 2 92 and the lower connecting block 2 92 are locked to each other by screws; The upper connecting block 1 91 , the connecting block 2 92 and the lower connecting block 1 91 , the connecting block 2 92 form a transition cavity corresponding to the mold cavity.

[0028] Furthermore, the mold cavity and the transition cavity are plated with a wear-resistant base layer, which is a hard chromium layer.

[0029] The specific usage and function of this embodiment are as follows: After being immersed in the resin glue, the external fiber bundle is introduced into the mold cavity at the preheating section 1. Since the preheating section 1 is provided with a wear-resistant block 71 and an introduction groove 72, when the fiber bundle immersed in the resin enters the introduction groove 72, the groove width and groove depth of the introduction groove 72 gradually decrease from the preheating section 1 to the gel section 2. The groove depth and groove width at the entrance are larger, guiding a large amount of resin to quickly enter and wrap the fiber; the groove depth and groove width gradually decrease along the pultrusion direction, the transition is gentle, and finally disappear completely, ensuring a steady pressure increase, promoting fiber infiltration and reducing bubble entrainment; At the same time, the high wear area of ​​the mold is mainly at the mold inlet where the fiber bundle is introduced. The wear-resistant block 71 is detachable and made of carbide, which makes the mold inlet have high wear resistance and can be easily replaced. The external system controls the heating rods 6 in the upper mold plate 51 and the lower mold plate 52 in the preheating section 1 to heat up to 80±1°C, preheating the fiber bundle inside the mold cavity and optimizing the resin viscosity. The preheated fiber bundle then enters the mold cavity in the gel section 2. The heating rod 6 in the gel section 2 is controlled to heat up again. The temperature gradient is adjusted from 120 to 160°C, gradually increasing from front to back to trigger the curing reaction. At the same time, the pultrusion speed of the external traction machine is matched. Then it enters the mold cavity in the curing section 3, and controls the heating rod 6 in the curing section 3 to heat up again, the temperature is 180±0.5℃, to achieve complete cross-linking, and ensure that the curing degree of the core layer is greater than 95%; Then, it enters the mold cavity in the cooling section 4, and controls the external water supply device to introduce water into the corresponding channel of the water channel prosthesis 81 through the water inlet hole. The water flows through the partition 83 and continuously circulates in the horizontal water channel and the vertical water channel, and finally flows out from the water outlet hole, thereby realizing water circulation cooling, and then shaping and reducing the mold temperature of the internal solidified plate; The final formed sheet is pulled out from the outlet of cooling section 4; The lower mold plate 52 and the upper mold base 54 are detachably mounted, thereby enabling the free replacement of molds with different cavities. Furthermore, the lower mold plate 52 and the upper mold base 54 are consumable parts, and the detachable design reduces subsequent maintenance costs and improves maintenance efficiency. When fixing and disassembling the preheating section 1, the gel section 2, the curing section 3, and the cooling section 4, first, the connecting block 1 91 and the connecting block 2 92 are fixedly installed with the corresponding upper template 51 and the lower template 52 through the plug blocks 93 thereon, and then the connecting block 1 91 and the connecting block 2 92 are locked to each other by screws, and the upper connecting block 2 92 and the lower connecting block 2 92 are locked to each other by screws, thereby realizing the fixed connection between the preheating section 1, the gel section 2, the curing section 3, and the cooling section 4. When disassembling, follow the above steps in reverse.

[0030] Since the upper mold base 54 in the preheating section 1, gel section 2, curing section 3, and cooling section 4 is provided with exhaust holes distributed in a triangular array in the middle, and the upper template 51 is provided with outlet holes corresponding to the exhaust holes, the distance between any two adjacent exhaust holes in the triangular array is equal (the sides of the equilateral triangles are of the same length), which can ensure that the "path length" of the gas in each area of ​​the mold cavity to the nearest exhaust hole is basically the same, avoiding the problem of local gas accumulation and inability to discharge.

[0031] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A forming die for composite pultruded sheets for wind turbine blades, comprising a preheating section (1), a gel section (2), a curing section (3), and a cooling section (4), characterized in that: The preheating section (1), gel section (2), solidification section (3), and cooling section (4) all include a mold body (5); the mold bodies (5) at the preheating section (1), gel section (2), solidification section (3), and cooling section (4) are all connected in sequence via a connecting assembly (9); and evenly distributed heating rods (6) are installed on the inner sides of the mold bodies (5) at the preheating section (1), gel section (2), and solidification section (3); A water cooling assembly (8) is installed inside the mold body (5) at the cooling section (4); The mold body (5) comprises an upper mold plate (51), a lower mold plate (52), a lower mold base (53), and an upper mold base (54). The upper mold plate (51) and the lower mold plate (52) are fixedly connected by evenly distributed screws. The upper mold base (54) is installed on the inner side of the upper mold plate (51), and the lower mold base (53) is installed on the inner side of the lower mold plate (52). A mold cavity is formed between the lower mold base (53) and the upper mold base (54).

2. The forming die for composite pultruded sheet material for wind turbine blades according to claim 1, characterized in that: The middle portion of the upper mold base (54) is provided with exhaust holes distributed in a triangular array, and the upper mold plate (51) is provided with outlet holes corresponding to the exhaust holes.

3. The forming die for the composite pultruded sheet material for wind turbine blades according to claim 1, characterized in that: Evenly distributed heating rods (6) are installed on the inner sides of the upper template (51) and the lower template (52) at the preheating section (1), the gel section (2), and the curing section (3).

4. The forming die for the composite pultruded sheet material for wind turbine blades according to claim 1, characterized in that: The heads of the lower mold base (53) and the upper mold base (54) at the preheating section (1) are fixedly mounted with wear-resistant parts (7), and the wear-resistant parts (7) include wear-resistant blocks (71) and introduction grooves (72). The heads of the lower mold base (53) and the upper mold base (54) are fixedly mounted with wear-resistant blocks (71) by screws, and the wear-resistant blocks (71) are provided with evenly distributed introduction grooves (72).

5. The forming die for the composite pultruded sheet material for wind turbine blades according to claim 1, characterized in that: The water cooling assembly (8) includes a water channel dummy (81), a copper plug (82), and a partition (83); the inner sides of the upper template (51) and the lower template (52) at the cooling section (4) are provided with a channel corresponding to the water channel dummy (81); the side channel openings of the upper template (51) and the lower template (52) are both threadedly connected with the copper plug (82); the upper template (51) and the lower template (52) are provided with a water inlet hole and a water outlet hole corresponding to the channel; The channel includes evenly distributed transverse waterways and vertical waterways connecting the transverse waterways, and the transverse waterways at both ends are connected to the water inlet and the water outlet respectively; A partition plate (83) is installed in all other transverse water channels except the transverse water channel connected to the water outlet, and an arc groove is provided at the head of the partition plate (83).

6. The forming die for the composite pultruded sheet material for wind turbine blades according to claim 1, characterized in that: A connecting assembly (9) is installed between adjacent upper templates (51) and lower templates (52), and the connecting assembly (9) includes a connecting block 1 (91), a connecting block 2 (92), and an inserting block (93). The inserting block (93) is fixedly installed on the connecting block 1 (91) and the connecting block 2 (92). The connecting block 2 (92) is engaged with the outer side of the connecting block 1 (91) and is locked with each other by screws. The upper template (51) and the lower template (52) are provided with grooves corresponding to the inserting block (93), and the inserting block (93) is fixed to the corresponding upper template (51) and the lower template (52) by screws. The upper connecting block 2 (92) and the lower connecting block 2 (92) are locked to each other by screws; The upper connecting block 1 (91), the connecting block 2 (92) and the lower connecting block 1 (91), the connecting block 2 (92) form a transition cavity corresponding to the mold cavity.

7. The forming die for the composite pultruded sheet material for wind turbine blades according to claim 4, characterized in that: The wear-resistant block (71) is made of hard alloy.

8. The forming die for the composite pultruded sheet material for wind turbine blades according to claim 4, characterized in that: The groove depth and groove width of the introduction groove (72) gradually decrease from the preheating section (1) to the gel section (2).

9. The forming die for the composite pultruded sheet material for wind turbine blades according to claim 6, characterized in that: The mold cavity and the transition cavity are plated with a wear-resistant bottom layer.

10. The forming die for the composite pultruded sheet material for wind turbine blades according to claim 9, characterized in that: The wear-resistant bottom layer is a hard chromium layer.

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