Prefabricated blade root structure of megawatt wind-powered electricity generation blade
Technical Field
The utility model relates to a megawatt level wind-powered electricity generation blade root prefab makes technical field, especially relates to a megawatt level wind-powered electricity generation blade's prefabricated blade root structure.
Background
A high-strength bolt is used in a wind generating set to connect a blade to a main engine hub, so that the load borne by the blade is transmitted to the hub, and the connection mode mainly comprises a T-shaped bolt connection mode and an embedded bolt sleeve connection mode. Wherein T type bolted connection adopts at the blade root, the axial drilling, place high strength bolt, radial drilling, the mode of placing cylindrical nut is assembled, this mode is widely used because have higher production efficiency and good quality controllability, but along with the development of wind-powered electricity generation trade, in order to improve wind energy utilization ratio and fan generated power, wind-powered electricity generation blade size is towards bigger, longer direction development, corresponding blade root moment of flexure, load also increases, T type bolted connection type will more and more unable satisfying blade root joint strength requirement, therefore, more and more "pre-buried set bolt" technique is used for blade root joint type, so that arrange more connecting bolt at the blade root, improve blade root joint strength and fatigue strength.
At present, the technology of 'pre-embedded bolt sleeves' of the blade root of the existing wind power blade adopts the method that a plurality of bolt sleeve assemblies are placed in the blade root along the blade root body at the blade root of the wind power blade, and every two bolt sleeve assemblies are fixed through a splicing body. The existing technology of 'pre-embedded bolt sleeve' has the following defects: the bolt sleeve is easy to accumulate rich resin nearby, the cavity is formed, the cavity is filled, the bolt sleeve is pulled out, the joint of the blade root and the hub is loosened and even falls off, namely the bolt sleeve is low in connection strength with the blade, the bonding force is low, the embedded bolt sleeve is difficult to axially position the blade root, rotation and translation are easy to occur, the positioning is not accurate enough, only one bolt sleeve and a UD block can be placed at each time, and the efficiency is low.
SUMMERY OF THE UTILITY MODEL
In view of the above, it is necessary to provide a prefabricated blade root structure of a megawatt wind turbine blade.
The prefabricated blade root structure of the megawatt wind power blade is characterized by comprising a blade body, wherein a bolt sleeve assembly, a combining piece and a butting piece are arranged in the blade body, the combining piece comprises an upper combining piece and a lower combining piece, the upper combining piece is positioned in the upper surface of the blade body, the lower combining piece is positioned in the lower surface of the blade body, a semi-cylindrical upper groove sunken towards the upper surface is formed in the lower surface of the upper combining piece, a semi-cylindrical lower groove sunken towards the lower surface is formed in the upper surface of the lower combining piece, the bolt sleeve assembly is positioned in a cylindrical space formed by the upper groove and the lower groove, and the butting piece is abutted and attached to one ends, far away from the root of the blade body, of the bolt sleeve assembly and the combining piece.
Furthermore, a plurality of flow guide holes which penetrate longitudinally and are vertical to the upper surface of the upper combining piece are uniformly formed in the upper combining piece.
Furthermore, a plurality of flow guide holes which penetrate longitudinally and are vertical to the lower surface of the lower combining piece are uniformly formed in the lower combining piece.
Further, the bolt sleeve assembly comprises a bolt sleeve and a winding glass fiber layer.
Further, the bolt sleeve comprises a sleeve and an external tooth form formed on the side surface of the sleeve.
Further, the winding glass fiber layer is wound on the outer surface of the bolt sleeve except for the sleeve, and the outer surface of the winding glass fiber layer is kept horizontal with the sleeve.
Furthermore, the upper surface of the upper combining piece is a circular arc surface, and the upper surface of the upper combining piece and the inner surface of the upper surface of the blade body keep the same shape and are tightly attached.
Further, the lower surface of the lower binder is a circular arc surface, and the lower surface of the lower binder and the inner surface of the lower surface of the blade body keep the same shape and are tightly attached.
Further, the radius of a cylindrical space formed by the upper groove and the lower groove is the same as the radius of the end face, close to the blade root, of the bolt sleeve assembly, and the cylindrical height of the cylindrical space is the same as the axial length of the bolt sleeve assembly.
Further, the lower surface of the abutting piece is an arc surface and is tightly attached to the lower surface of the blade body, the shape of the upper surface of the abutting piece is kept consistent with that of the inner surface of the upper surface of the blade body, and the upper surface of the abutting piece comprises an arc surface and a conical surface.
According to the prefabricated blade root structure of the megawatt wind power blade, the positioning and the assembling are carried out through the combination of the bolt sleeve assembly, the upper combining piece and the lower combining piece, so that the positioning is more accurate, and the assembling efficiency is improved; and utilize the surface shape that the conjunction and butt piece are the same with the blade body for the clearance between prefab and the pouring body is little, thereby increases joint strength, simultaneously through seting up the water conservancy diversion hole on the conjunction, is convenient for the flow of resin, has prevented effectively that rich resin from piling up, the condition in cavity, pouring cavity.
Drawings
FIG. 1 is a schematic structural diagram of a prefabricated blade root structure of a megawatt wind turbine blade according to an embodiment;
FIG. 2 is a schematic structural diagram of a prefabricated blade root structure of a megawatt wind turbine blade according to yet another embodiment;
FIG. 3 is a schematic view of a prefabricated blade root structure of a megawatt wind turbine blade according to yet another embodiment;
FIG. 4 is a schematic structural view of an upper coupling member in one embodiment;
FIG. 5 is a schematic view of the lower coupling member in one embodiment;
FIG. 6 is a schematic structural view of an upper coupling member in still another embodiment;
FIG. 7 is a schematic structural view of a lower coupling member in still another embodiment;
FIG. 8 is a schematic structural view of an upper coupling member in another embodiment;
FIG. 9 is a schematic view showing a lower coupling member in another embodiment;
FIG. 10 is a schematic view of the structure of the abutment member in one embodiment;
FIG. 11 is a cross-sectional view of the bolt bushing assembly in the axial direction according to one embodiment;
FIG. 12 is a schematic view showing a combination of the engaging member and the abutting member in one embodiment;
FIG. 13 is a schematic view showing a combination of the engaging member and the abutting member in another embodiment.
In the drawing, a blade body 1, an upper surface 110 of the blade body, a lower surface 120 of the blade body, a bolt sleeve assembly 2, a bolt sleeve 21, a sleeve 211, an outer thread 212, an inner wall thread 213, a seal ring groove 214, a funnel-shaped structure 215, a winding glass fiber layer 22, a combining member 3, an upper combining member 310, an upper surface 311 of the upper combining member, an upper groove 312, a lower combining member 320, a lower surface 321 of the lower combining member, a lower groove 322, a diversion hole 330, an abutting member 4, a lower surface 401 of the abutting member, an arc surface 402 of the abutting member, and a conical surface 403 of the abutting member.
Detailed Description
In order to make the present invention more clearly understood, the present invention will be described in further detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
As shown in fig. 1, 4, 5, 10 and 12, a prefabricated blade root structure of a megawatt wind turbine blade is provided, which includes a blade body 1, a plurality of bolt sleeve assemblies 2, a plurality of coupling members 3 and a plurality of abutting members 4 are arranged in the blade body 1, and each coupling member 3 includes an upper coupling member 310 and a lower coupling member 320. The plurality of bolt bushing assemblies 2, the plurality of coupling members 3 and the plurality of abutting members 4 are arranged in accordance with the arc-shaped structure of the root of the blade body 1. The bolt bushing assembly 2 is made of 42CrMoA or 42CrMo alloy steel and is circumferentially spaced along the root. The surface of the lower coupler 320 of each upper coupler 310 coincides with the inner surface of the blade body 1. The upper connector 310 is located in the upper surface of the blade body 1, the lower connector 320 is located in the lower surface of the blade body 1, the lower surface of the upper connector 310 is provided with a semi-cylindrical upper groove 312 which is recessed towards the upper surface 311, the upper surface of the lower connector 320 is provided with a semi-cylindrical lower groove 322 which is recessed towards the lower surface 321, the bolt sleeve assembly 2 is located in a cylindrical space formed by the upper groove 312 and the lower groove 322, and the abutting part 4 abuts against and is attached to one end, away from the root of the blade body 1, of the bolt sleeve assembly 2 and the connector 3. Similarly, the lower surface 401, the arc surface 402 and the conical surface 403 of the contact member 4 are all adhered to the inner surface of the blade body 1, and the overall transverse length of the contact member 4 is larger than that of each of the coupling members 3 during machining. Preferably, when the abutting parts 4 are assembled, the assembling position between every two abutting parts 4 needs to be staggered with the assembling position between two adjacent combining parts 3, so that the condition that all the abutting parts are rich in resin in a certain longitudinal direction can be prevented when resin is poured, and the connecting strength and the fatigue strength are increased.
In the above embodiment, the positioning is performed by combining the bolt sleeve assembly 2 and the joint member 3, so that the positioning is more accurate, and meanwhile, the clearance between the prefabricated member and the pouring body is small by using the same surface shapes of the joint member 3 and the abutting member 4 as those of the blade body 1, so that the connection strength is increased.
In one embodiment, the upper bonding member 310 has a plurality of flow guiding holes 330 extending longitudinally and perpendicular to the upper bonding member upper surface 311. Specifically, the diversion holes 330 may be disposed on a line segment where the lowest point of the upper groove 312 is located, and may also be disposed on a line segment where the respective central points of the arc segments on both sides of the upper groove 312 are located, where the diversion holes 330 are uniformly distributed. Wherein, it is preferable that the initial position of the guiding holes 330 is 30mm away from the upper connector 310 towards the end surface of the blade root, and every 50mm along the length direction is provided with one guiding hole 330, and the guiding holes 330 are used for resin injection. The upper combining member 310 is provided with the flow guide holes 330, so that resin can flow conveniently, and the conditions of resin accumulation, cavities and filling cavities are effectively prevented.
In one embodiment, as shown in fig. 5, the lower bonding member 320 is uniformly provided with a plurality of flow guiding holes 330 which are longitudinally penetrated and perpendicular to the lower surface of the lower bonding member. Specifically, the diversion holes 330 may be disposed on a line segment where the lowest point of the lower groove 322 is located, and may also be disposed on a line segment where the respective center points of the arc segments on both sides of the lower groove 322 are located, where the diversion holes 330 are uniformly distributed. Wherein, it is preferable that the initial position of the guiding holes 330 is 30mm away from the lower connector 320 towards the end surface of the blade root, and every 50mm along the length direction is provided with one guiding hole 330, and the guiding holes 330 are used for resin injection. The lower combining member 320 is provided with the flow guide holes 330, so that resin can flow conveniently, and the conditions of resin accumulation, cavities and filling cavities are effectively prevented.
In one embodiment, as shown in fig. 11, the bolt housing assembly 2 includes a bolt housing 21 and a wrapped fiberglass layer 22, the bolt housing 21 includes a sleeve 211 and an external profile 212 formed on the side of the sleeve, and the bolt housing 21 is provided with internal wall threads 213 therein. A seal groove 214 is formed between the inner wall thread 213 of the sleeve 211 and the opening of the rear end of the sleeve for installing a seal so that the poured resin does not enter the area of the inner wall thread 213 when the blade is poured. The opening at the tail end of the sleeve 211 is tapered inward to form a funnel-shaped structure 215, and the tapered trend is cut into the seal ring groove 214, that is, the opening at the tail end of the sleeve 211 is dovetail-shaped as seen in fig. 11, so that the rigidity of the tail part is smoothly transited, and the sudden change of the rigidity of the fiber structure after pouring can be avoided, thereby improving the overall strength and fatigue performance of the blade root. The intersection of any cross section through the axis of the collar 211 with the outer profile 212 is an arc, where the arc is a circular arc. Preferably, the radius of the circular arc is 6.5-8 mm, at the moment, the distance from the center of the circular arc to the end face of the excircle of the sleeve is 4.2-4.8 mm, and the distance between the centers of adjacent circular arcs is 16-20 mm.
In one embodiment, as shown in fig. 11, the winding glass fiber layer 22 is wound around the outer surface of the bolt sleeve 21 except for the sleeve 211, and the outer surface of the winding glass fiber layer 22 is kept horizontal with the sleeve 211. Specifically, the winding glass fiber layer 22 is a winding glass fiber layer, and is used for curing after resin is poured, so that the fatigue strength of the bolt sleeve assembly 2 and the connection member 3 are improved while the adhesion between the bolt sleeve assembly 2 and the connection member 3 is ensured.
In one embodiment, the upper surface 311 of the upper bonding member 310 is a circular arc surface, the upper surface 311 of the upper bonding member 310 and the inner surface of the upper surface of the blade body 1 keep the same shape and are tightly attached, and the attachment of the same shape of the attachment surface can make the gap between the prefabricated member and the pouring body small, so that the connection strength is increased, and the glass fiber reinforced plastic joint part has a simple structure and is convenient and quick to machine and form.
In one embodiment, the lower surface 321 of the lower bonding member 320 is a circular arc surface, the lower surface 321 of the lower bonding member 320 and the inner surface of the lower surface of the blade body 1 keep the same shape and are tightly attached, and the attachment of the same shape of the attachment surface can make the gap between the prefabricated member and the pouring body small, so that the connection strength is increased, and the glass fiber reinforced plastic bonding part has a simple structure and is convenient and quick to machine and form.
In one embodiment, the radius of the cylindrical space formed by the upper groove 312 and the lower groove 322 is the same as the radius of the end of the bolt sleeve assembly 2 near the root of the blade body, and the cylindrical height of the cylindrical space is the same as the axial length of the bolt sleeve assembly 2, so that the bolt sleeve assembly 2 is tightly attached to the joint member 3 through the control of the length and the radius.
In one embodiment, the lower surface 401 of the abutment member 4 is a circular arc surface and is tightly attached to the lower surface of the blade body 1, the upper surface of the abutment member 4 is consistent with the inner surface shape of the upper surface of the blade body, the upper surface of the abutment member includes a circular arc surface 402 and a conical surface 403, and the tight attachment to the blade body 1 can be ensured by designing the same shape as the blade body 1.
In one embodiment, as shown in fig. 2, 6 and 7, the upper and lower coupling members 310 and 320 of the coupling member 3 are provided with a plurality of upper grooves 311 and a plurality of lower grooves 321, and fig. 2 shows a structure in which two grooves are formed in each of the upper and lower coupling members 310 and 320, but the actual number of grooves is not limited to two, and may be more than two, and may be 3, 4, etc. The corresponding pilot holes 330 in each of the upper and lower couplers 310 and 320 are also uniformly arranged. Two rows of baffle holes 330 may be provided intermediate the two grooves as shown in fig. 7, as may one or more rows of baffle holes. Except that the number of the grooves on one upper engaging member 310 or one lower engaging member 320 is more than one, the other structures are the same as those in the corresponding embodiment of fig. 1, and therefore, the description thereof is omitted. The adoption of the plurality of grooves on the upper combining piece 310 and the lower combining piece 320 reduces the production time and improves the production efficiency in the processing aspect of the combining pieces; when assembling, because conjunction 3 itself grow for assembling to same wind-powered electricity generation blade root, the conjunction 3 quantity that needs the concatenation reduces, thereby has improved and has assembled efficiency.
In one embodiment, as shown in fig. 3, 8, 9 and 13, a prefabricated blade root structure of a megawatt wind turbine blade is provided with the coupling members 3 staggered up and down in a multi-groove shape, which is different from the embodiment shown in fig. 1 in that first, each of the upper and lower coupling members 310 and 320 is provided with a plurality of upper grooves 312 and a plurality of lower grooves 322; secondly, the upper and lower coupling members 310 and 320 are combined in a staggered manner, and although each upper groove 312 still corresponds to one lower groove 322, the upper coupling member 310 is no longer aligned with the lower coupling member 320. Other structures are the same as those in the embodiment corresponding to fig. 1, and therefore are not described herein again. The embodiment adopts the form of multi-groove up-and-down dislocation, which is more beneficial to positioning and assembling and improves the assembling efficiency, and through the dislocation of the up-and-down conjunction and the dislocation of the conjunction 3 and the abutting part 4, each longitudinal direction of the blade root structure can be effectively ensured to be an entity with the conjunction 3 or the abutting part 4, thereby preventing the situation that a certain longitudinal direction is rich in resin when resin is poured, and further increasing the connection strength and the fatigue strength.
The foregoing is a more detailed description of the present invention that is presented in conjunction with specific embodiments, and it is not to be understood that the specific embodiments of the present invention are limited to these descriptions. To the utility model belongs to the technical field of ordinary technical personnel, do not deviate from the utility model discloses under the prerequisite of design, can also make a plurality of simple deductions or replacement, all should regard as belonging to the utility model discloses a protection scope.