Blade positioning measurement and correction method
By setting an initial positioning point group on the turbine blade and combining the six-point positioning principle with industrial CT scanning, the problem of wall thickness parameter accuracy in turbine blade casting inspection was solved, achieving efficient measurement and correction and improving the casting pass rate.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-28
- Publication Date
- 2026-03-27
AI Technical Summary
In the existing technology, it is difficult to accurately determine whether the appearance and dimensions of turbine blade castings are up to standard during inspection, especially the wall thickness parameter, which is difficult to control accurately, resulting in a low casting pass rate.
By setting an initial set of positioning points on the turbine blade and theoretical 3D model, the spatial degrees of freedom are constrained by the six-point positioning principle. The external dimensions are measured by point measurement and three-coordinate line scanning to obtain cross-sectional images. Internal dimension data is obtained by industrial CT scanning. The positioning point set is then updated to determine the deviation limit points and targeted adjustments are made.
It enables precise and rapid measurement and correction of turbine blades, improves the pass rate of castings, avoids the problem of wall thickness reduction caused by blind trimming, and ensures the accuracy of measurement and the practicality of trimming.
Smart Images
Figure CN121739942A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of turbine blade measurement technology, specifically a method for blade positioning measurement and correction. Background Technology
[0002] The quality of castings directly affects the service life and safety of products. In the full-dimensional inspection of castings, six-point positioning is a crucial inspection technique. It uses 3D scanning and high-precision matching with the product's digital model to accurately determine whether the product's external dimensions are up to standard. For hollow cast blades, wall thickness is an extremely important indicator, determined by both the blade's external and internal dimensions. For surface finishing of blade castings, accurately grasping the relationship between the external and internal dimensions can improve the blade casting pass rate. Summary of the Invention
[0003] To address the problems existing in the prior art, this invention provides a method for blade positioning measurement and correction, enabling accurate and rapid measurement of turbine blades.
[0004] This invention is achieved through the following technical solution: A method for measuring and correcting blade positioning includes the following steps: Step 1: Set an initial set of positioning points on the turbine blade to be tested and its corresponding theoretical three-dimensional model, and constrain the spatial degrees of freedom of the turbine blade through the initial set of positioning points. Step 2: Construct a benchmark measurement system using the initial positioning point set, and measure the external dimensional parameters at different height positions along the blade height direction; Step 3: Under the condition that the turbine blade and the theoretical 3D model are in the same attitude, obtain cross-sectional images corresponding to different height positions, and the height information of each cross-sectional image corresponds one-to-one with the height position of the measured external dimensions. Step 4: Based on the size comparison results between the cross-sectional image and the theoretical 3D model, determine the limit points of blade size deviation; Update the spatial position of the initial positioning point group based on the location information of the extreme point, and generate a new positioning point group; Step 5: Using the newly generated set of positioning points as the reference measurement system, perform a second measurement on the turbine blade's external dimensions, and combine the external dimensions data from the first measurement of the initial set of positioning points to carry out targeted adjustments to the turbine blade's surface.
[0005] Preferably, the method for constraining the spatial degrees of freedom of the turbine blade by setting the initial positioning point set is as follows: Based on the six-point positioning principle, six positioning points are set on the turbine blade. The six positioning points constrain the turbine blade's translational degrees of freedom along the X, Y, and Z axes and its rotational degrees of freedom around these three axes, making the turbine blade's spatial position unique.
[0006] Preferably, the positioning settings of the six points in the initial positioning point group are as follows: Point A1 is located on the suction side of the leaf blade, A2 and A3 are located on the suction side of the leaf root, B4 and B5 are located on the leading edge of the leaf blade, and point C is located on the surface of platform region 4.
[0007] Preferably, the measurement of external dimensions at different height positions includes: The cross-sectional dimensions of the blade at different heights were measured using point measurement and three-coordinate line scanning methods.
[0008] Preferably, acquiring cross-sectional images at different height positions includes: Tooling was used to adjust the attitude of the turbine blades to make them consistent with the theoretical three-dimensional model; Industrial CT scanners were used to scan turbine blades and obtain cross-sectional images at different heights.
[0009] Preferably, determining the limit points of blade size deviation based on the cross-sectional image and the dimensions of the theoretical three-dimensional model includes: The wall thickness measurement values of each detection point on the blade are obtained from the cross-sectional image. The wall thickness measurement value of each detection point is compared with the wall thickness value of the corresponding detection point in the theoretical model to determine the detection point with the largest wall thickness deviation.
[0010] Preferably, the step of updating the position of the initial positioning point group based on the extreme points of the blade size deviation to obtain a new positioning point group includes: The initial positioning point on the suction side of the blade is moved to the limit point of the blade size deviation and used as the reference point. Other initial positioning points in the initial positioning point group are then updated to form a new initial positioning point group.
[0011] Preferably, the update method for other initial positioning points in the initial positioning point group is as follows: The two initial positioning points in the petiole region are moved synchronously to the petiole region on the same side as the reference point to form a new set of initial positioning points.
[0012] Preferably, step 5, which involves measuring the blade's shape using the new set of positioning points as a reference system, includes: The shape of the blade is measured using point measurement or three-coordinate line scanning measurement, and the measurement height is the same as that of S2.
[0013] Preferably, the blade surface is trimmed, and the trimmed surface is the opposite side of the surface corresponding to the blade positioning point in the new positioning point group.
[0014] Compared with the prior art, the present invention has the following beneficial technical effects: This application provides a method for measuring and correcting turbine blade positioning. First, by setting an initial set of positioning points and constraining the degrees of freedom on the turbine blade and its theoretical 3D model, a precise benchmark is established using the six-point positioning principle, providing a stable reference for subsequent measurements and ensuring the accuracy of the initial external dimensions. Second, the external dimensions are measured along the blade height direction and the corresponding cross-sectional image is obtained, establishing a correlation between the blade's external dimensions and internal structural data, providing complete data support for deviation analysis. Furthermore, the limit points of dimensional deviation are determined based on the comparison between the cross-sectional image and the theoretical model, thereby updating the positioning point set. This allows subsequent measurement benchmarks to focus on key deviation areas, improving measurement specificity. Third, the external dimensions are remeasured using the new positioning point set, and the blade surface is adjusted based on the initial measurement data. This allows for precise adjustment of the surface to be adjusted while protecting the deviation limit areas (such as areas with thinner walls), effectively avoiding further wall thinning caused by blind adjustment, significantly improving the pass rate of hollow turbine blade castings, balancing measurement accuracy and adjustment practicality, and is suitable for high-quality turbine blade inspection and correction scenarios. Attached Figure Description
[0015] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0016] Figure 1 This is a diagram showing the arrangement of positioning points for the turbine blade of the present invention. Figure 2 This is a schematic cross-sectional view of the turbine blade of the present invention; Figure 3 This is a schematic diagram showing the position of the positioning point after the relocation according to the present invention; Figure 4 This is a flowchart of the measurement and correction method of the present invention.
[0017] In the diagram: 1. Turbine blade; 2. Blade area; 3. Root area; 4. Plateau area; 5. Pressure side; 6. Suction side; 7. Leading edge; 8. Trailing edge; Detailed Implementation To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.
[0018] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.
[0019] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.
[0020] In the description of the embodiments of this application, it should be noted that if terms such as "upper," "lower," "horizontal," or "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use, they are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. In addition, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.
[0021] Furthermore, the use of the term "horizontal" does not imply that the component must be absolutely horizontal, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.
[0022] In the description of the embodiments of this application, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.
[0023] A method for measuring and correcting blade positioning includes the following steps: Step 1: Set the initial positioning point group on the turbine blade to be measured and the corresponding theoretical three-dimensional model; Based on the six-point positioning principle, an initial set of positioning points is set on the turbine blade to be measured and its corresponding theoretical 3D model. These rationally distributed positioning points constrain the blade's translational degrees of freedom along the X, Y, and Z axes, as well as its rotational degrees of freedom around these axes, ensuring the blade's unique position in space. Its core function is to establish a unified and stable benchmark system for all subsequent measurement operations, eliminating measurement deviations caused by uncertain spatial attitudes of the blade, and ensuring that subsequent steps such as dimensional measurements and cross-sectional image acquisition are based on a consistent reference standard.
[0024] Step 2: Using the initial positioning point group as a reference system, measure the external dimensions at different height positions along the blade height direction of the turbine blade; Using the initial positioning point set determined in step 1 as a reference, the external dimensions at different height positions along the height direction of the turbine blade are measured. High-precision measurement methods such as point measurement and coordinate measuring machine (CMM) scanning can be employed. The principle is to rely on a stable reference to ensure the spatial consistency of the measurement data and avoid dimensional data confusion caused by reference changes. Its function is to obtain specific dimensional information of the blade's external contour at different heights, forming a preliminary data archive of the blade's shape. This provides an external dimensional reference for the height correspondence between subsequent cross-sectional images and external dimensions, and also provides initial shape data for the final blade surface finishing.
[0025] Step 3: With the turbine blade in the same orientation as the theoretical 3D model, obtain cross-sectional images at different heights, and the height of the cross-sectional images corresponds to the height of the outer dimensions. This step first adjusts the turbine blade's attitude using tooling to match the theoretical 3D model, ensuring they are in the same coordinate system. Then, industrial CT scanning is used to acquire a cross-sectional image corresponding to the height measured in step 2. The principle is to utilize industrial CT's "ray scanning-projection acquisition-tomographic reconstruction" technology to penetrate the blade structure and generate a high-precision internal cross-sectional image. The consistent attitude and height ensure spatial correlation between the cross-sectional image and the overall dimensional data. Its purpose is to obtain specific information about the blade's internal structure (such as wall thickness) at different heights, filling the gap in internal dimensional data that cannot be obtained by simply measuring the external shape, and providing a complete basis for comparing internal and external dimensions for subsequent deviation analysis.
[0026] Step 4: Determine the limit points of blade size deviation based on the cross-sectional image and the dimensions of the theoretical 3D model. Update the position of the initial positioning point group based on the limit points of blade size deviation to obtain a new positioning point group.
[0027] By comparing the cross-sectional image obtained in step 3 with the dimensions of the theoretical 3D model, the dimensional deviations of each detection point on the blade (such as the wall thickness detection point) are calculated, the extreme point with the largest deviation is determined, and the initial positioning point group is updated with this point as the core. The principle is to accurately locate the key error area of the blade based on the internal dimensional deviation, focusing the positioning benchmark on the part that has the greatest impact on the blade quality (such as the extreme point where the wall thickness is too thin). The purpose is to make the subsequent measurement benchmark more closely match the actual error condition of the blade, avoid the problem of ignoring the key deviation area when measuring with the initial benchmark, provide more targeted benchmark support for precise adjustment, and prevent subsequent adjustment from causing further adverse effects on the deviation limit area (such as further thinning of the wall thickness).
[0028] Step 5: Measure the shape of the blade using the new set of positioning points as the reference system. Based on the measured blade dimensions and the dimensions measured using the initial set of positioning points, trim the blade surface.
[0029] Based on the updated positioning point set, the blade shape is remeasured at the same height as in step 2. Then, combining the initial and remeasured dimensional data, the blade surface is trimmed. The principle is to obtain the latest dimensions of the blade shape around the critical deviation area using the updated precise benchmark. By comparing the two measurement data, the trimmable area (such as the redundant dimension area opposite the deviation limit point) is identified. Its function is to selectively remove redundant dimensions from the blade surface while protecting critical deviation areas (such as areas with thinner walls), bringing the shape profile into the allowable tolerance range. This avoids blade quality problems caused by blind trimming, significantly improves the pass rate of hollow turbine blade castings, and achieves closed-loop precise control of measurement and trimming.
[0030] See Figure 1 Turbine blades have a blade region 2, a root region 3, and a plateau region 4. For the entire turbine blade, regardless of whether it's the blade region, the root region, or the plateau region, they all share the same orientation, i.e., as shown... Figure 2 5. Pressure side, 6. Suction side, 7. Leading edge (side) direction, and 8. Trailing edge (side) direction.
[0031] In some embodiments, the initial positioning point group includes 6 positioning points, which are respectively set in the blade region, the leaf root region, and the leaf root region to form triaxial positioning of the turbine blade, namely axial, circumferential and horizontal.
[0032] Six positioning points are arranged on the turbine blade according to the six-point positioning principle. Any workpiece has six degrees of freedom in a spatial rectangular coordinate system, namely, translational degrees of freedom along the X, Y, and Z axes and rotational degrees of freedom about these three axes. The six-point positioning principle uses six corresponding fixed constraint points to simultaneously eliminate these six degrees of freedom, making the position of the workpiece in space uniquely determined.
[0033] Prior to this, point A1 is located on the suction side of the leaf blade, A2 and A3 are located on the suction side of the leaf root, B4 and B5 are located on the leading edge of the leaf blade, and point C is located on the surface of platform region 4.
[0034] In some embodiments, point measurement and three-coordinate line scanning measurement are used to measure the cross-sectional dimensions of the blade at different heights.
[0035] In some embodiments, industrial CT scans are used to scan the cross-section of the blade to obtain cross-sectional images at different heights, and the blade wall thickness is determined based on the cross-sectional images.
[0036] Industrial CT (Industrial Computed Tomography) is a non-destructive testing (NDT) technology. Essentially, it scans industrial parts with penetrating rays (such as X-rays and gamma rays) and combines them with computer algorithms to reconstruct three-dimensional structural images of the parts' internal and external structures, achieving "non-destructive, visualized, and high-precision" inspection and measurement.
[0037] Industrial CT obtains high-precision cross-sectional images of blades through "radio scanning → projection acquisition → tomographic reconstruction," and then uses the logic of "grayscale difference identification of structural boundaries + spatial calibration to convert dimensions + distance calculation of wall thickness" to achieve accurate measurement of blade wall thickness. Its core value is to provide full-size, high-precision internal and external dimensional data by penetrating complex structures "without damaging the workpiece."
[0038] In some embodiments, an industrial CT is provided with a fixture for adjusting the pose of a turbine blade. The turbine blade is connected to the fixture, thereby adjusting the pose of the blade to make it consistent with the pose of the theoretical three-dimensional model in the reference system.
[0039] Example 1 A blade positioning measurement method includes the following steps: S1. Set up an initial set of positioning points on the turbine blade to be measured and the corresponding theoretical three-dimensional model, and perform three-dimensional positioning of the turbine blade. The initial positioning point group consists of six points, respectively located on the suction side of the blade, the inlet side, and the platform flow channel surface. (See also...) Figure 1 Point A1 is located on the suction side of the leaf blade, A2 and A3 are located on the suction side of the leaf root, B4 and B5 are located on the leading edge of the leaf blade, and point C is located on the surface of platform region 4.
[0040] S2. Using the initial positioning point as a reference system, measure the shape of the blade and obtain shape data of different cross-sectional positions of the blade body and petiole area along the blade height direction.
[0041] Measurement methods include point measurement and coordinate measuring machine (CMM) scanning measurement.
[0042] S3. Adjust the attitude of the turbine blade to match that of the theoretical 3D model. Then, measure the cross-sectional images of the blade at different heights along the blade height direction, and ensure that the shape data corresponds to the height of the cross-sectional images.
[0043] Reference Figure 3 Since the blade root of the turbine blade may be unstable during the casting stage, it is necessary to process additional tooling based on 6 initial positioning points for industrial CT measurement to transform the blade's pose into an "upright state" consistent with the theoretical model. In this state, the turbine blade and the theoretical 3D model are located in the same reference coordinate system. Industrial CT is used to measure the blade body in this reference coordinate system to obtain cross-sectional images at different height positions.
[0044] S4. Obtain the wall thickness measurement value of the blade based on the cross-sectional image. Compare the wall thickness measurement value of each detection point with the wall thickness value of the detection point corresponding to the theoretical model. Determine the detection point with the largest wall thickness deviation. Move the initial positioning point on the suction side of the blade to this position and use it as the reference point. Simultaneously move the two initial positioning points in the petiole area to the petiole area on the same side as the reference point to form a new initial positioning point group.
[0045] The blade wall thickness was evaluated based on cross-sectional images of the blade obtained from industrial CT scans. According to the wall thickness data of multiple sections along the blade height, the initial positioning point on the suction side of the blade was moved to a region with thinner wall thickness on the pressure side or suction side. Two initial positioning points located in the petiole region were simultaneously moved to the same side as the moved position of the initial positioning point on the suction side of the blade.
[0046] The initial positioning point on the suction side of the blade is moved to the pressure side or a region with a thinner wall on the suction side, as follows: Move the initial positioning point on the suction side of the blade to the point where the local wall thickness on the pressure side or suction side of all measured sections of the blade is the largest difference from the theoretical wall thickness at the same location.
[0047] For example Figure 3 When measuring the blade's external shape using a coordinate measuring machine (CMM) and when using an industrial CT scanner to perform layer-by-layer measurements of the blade's internal structural contours, the same blade height cross-section is used for both measurements. After completing the industrial CT measurement, the wall thickness measurements at different points on the blade's cross-section can be obtained. Generally, wall thickness detection points are arranged for each internal cavity channel of the blade. During data processing, the measured wall thickness values at the detection points are compared with the theoretical wall thickness values at the same locations in the theoretical model to obtain the wall thickness deviation. The wall thickness deviation for each measurement cross-section can be positive or negative, with a positive deviation indicating that the wall thickness is too thick at that point and a negative deviation indicating that the wall thickness is too thin at that point.
[0048] After statistically analyzing the wall thickness deviations of all measured sections, the point with the greatest wall thickness reduction, i.e., the point with the largest negative wall thickness deviation, can be identified. At this point, regardless of whether this point is located on the pressure side or the suction side, the initial positioning point on the suction side of the blade will be moved to this point. This is to ensure that during subsequent blade shaping adjustments, this point will not experience further wall thickness reduction. In cases of uneven wall thickness caused by the offset of the hollow blade's ceramic core, moving the positioning point to this location ensures that further thinning will not occur at this point. On the opposite side of the blade profile at this location, further shaping of the blade's outline can then be performed.
[0049] Finally, the two initial positioning points in the petiole region are moved synchronously to the same side as the position of the initial positioning point on the suction side of the blade, meaning all three points are located on either the pressure or suction side of the blade. At this point, there will be six new positioning points.
[0050] S5. Using the new set of positioning points as a reference system, measure the shape of the blade. Based on the measured blade shape dimensions and combined with the shape dimensions measured by the initial set of positioning points, adjust the blade surface. The main area to be adjusted is generally the shape opposite the three moving positioning points. The shape dimensions here are generally too large. Adjustment can bring the shape profile into the allowable tolerance range.
[0051] The measurement and trimming method of this invention, after performing internal structure measurements using industrial CT, identifies the location of the thinnest internal wall thickness of the blade. This protects the wall thickness at this location during dimensional trimming, improving the yield rate of hollow blade castings. Furthermore, by measuring the blade's external dimensions and internal structure, the internal state of the blade in a specific orientation is obtained. Given potential dimensional deviations in the actual cast blade, targeted dimensional trimming is performed, avoiding the problems of blind trimming leading to further wall thinning. Trimming is carried out on surfaces with sufficient trimming margin, further improving the yield rate of hollow blade castings.
[0052] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.
Claims
1. A method for measuring and correcting blade positioning, characterized in that, It includes the following steps: Step 1: Set an initial set of positioning points on the turbine blade to be tested and its corresponding theoretical three-dimensional model, and constrain the spatial degrees of freedom of the turbine blade through the initial set of positioning points. Step 2: Construct a benchmark measurement system using the initial positioning point set, and measure the external dimensional parameters at different height positions along the blade height direction; Step 3: Under the condition that the turbine blade and the theoretical 3D model are in the same attitude, obtain cross-sectional images corresponding to different height positions, and the height information of each cross-sectional image corresponds one-to-one with the height position of the measured external dimensions. Step 4: Based on the size comparison results between the cross-sectional image and the theoretical 3D model, determine the limit points of blade size deviation; Update the spatial position of the initial positioning point group based on the location information of the extreme point, and generate a new positioning point group; Step 5: Using the newly generated set of positioning points as the reference measurement system, perform a second measurement on the turbine blade's external dimensions, and combine the external dimensions data from the first measurement of the initial set of positioning points to carry out targeted adjustments to the turbine blade's surface.
2. The blade positioning measurement and correction method according to claim 1, characterized in that, The method for constraining the spatial degrees of freedom of the turbine blade by setting the initial positioning point set is as follows: Based on the six-point positioning principle, six positioning points are set on the turbine blade. The six positioning points constrain the turbine blade's translational degrees of freedom along the X, Y, and Z axes and its rotational degrees of freedom around these three axes, making the turbine blade's spatial position unique.
3. The blade positioning measurement and correction method according to claim 2, characterized in that, The positioning settings for the six points in the initial positioning point group are as follows: Point A1 is located on the suction side of the leaf blade, A2 and A3 are located on the suction side of the leaf root, B4 and B5 are located on the leading edge of the leaf blade, and point C is located on the surface of platform region 4.
4. The blade positioning measurement and correction method according to claim 1, characterized in that, The measurement of external dimensions at different height positions includes: The cross-sectional dimensions of the blade at different heights were measured using point measurement and three-coordinate line scanning methods.
5. The blade positioning measurement and correction method according to claim 1, characterized in that, The acquisition of cross-sectional images at different height positions includes: Tooling was used to adjust the attitude of the turbine blades to make them consistent with the theoretical three-dimensional model; Industrial CT scanners were used to scan turbine blades and obtain cross-sectional images at different heights.
6. The blade positioning measurement and correction method according to claim 1, characterized in that, The process of determining the limit points of blade size deviation based on the cross-sectional image and the dimensions of the theoretical three-dimensional model includes: The wall thickness measurement values of each detection point on the blade are obtained from the cross-sectional image. The wall thickness measurement value of each detection point is compared with the wall thickness value of the corresponding detection point in the theoretical model to determine the detection point with the largest wall thickness deviation.
7. The blade positioning measurement and correction method according to claim 3, characterized in that, The step of updating the position of the initial positioning point group based on the extreme points of the blade size deviation to obtain a new positioning point group includes: The initial positioning point on the suction side of the blade is moved to the limit point of the blade size deviation and used as the reference point. Other initial positioning points in the initial positioning point group are then updated to form a new initial positioning point group.
8. The blade positioning measurement and correction method according to claim 7, characterized in that, The update method for other initial positioning points in the initial positioning point group is as follows: The two initial positioning points in the petiole region are moved synchronously to the petiole region on the same side as the reference point to form a new set of initial positioning points.
9. The blade positioning measurement and correction method according to claim 1, characterized in that, Step 5, which involves measuring the blade's shape using the new set of positioning points as a reference system, includes: The shape of the blade is measured using point measurement or three-coordinate line scanning measurement, and the measurement height is the same as that of S2.
10. The blade positioning measurement and correction method according to claim 1, characterized in that, The blade surface is trimmed, and the trimmed surface is the opposite side of the surface corresponding to the blade positioning point in the new positioning point group.