Three-coordinate detection and evaluation method for dovetail mortise of outer ring of stationary blade ring of gas turbine

Abstract

The invention provides a three-coordinate detection and evaluation method for a dovetail mortise of an outer ring of a stationary blade ring of a gas turbine. The three-coordinate detection and evaluation method comprises the following steps: S1, acquiring the outer ring and placing the outer ring on a three-coordinate platform; s2, importing a digital model, and collecting outer ring reference elements according to design reference requirements to establish a coordinate system; s3, the size elements of the outer ring mortise are deconstructed; and S4, geometrical characteristics in the mortise are collected through a three-coordinate probe, size elements are constructed, and whether the requirements are met or not is judged according to a tolerance threshold value. According to the method, calculation is carried out by adopting corresponding geometric feature data aiming at each dimension element, so that a measured value is obtained and tolerance judgment is carried out. According to the invention, batch detection is realized by using the three-coordinate turntable, so that the measurement efficiency is greatly improved. According to the method, the measurement precision and efficiency of the outer ring mortise of the stationary blade ring of the gas turbine are remarkably improved, and reliable guarantee is provided for product quality control.

Description

Technical Field

[0001] The invention belongs to the technical field of mortise and tenon detection, and in particular relates to a three-coordinate detection and evaluation method for a dovetail mortise and tenon groove of an outer ring of a gas turbine stator ring. Background Art

[0002] Precision measurement of the outer ring tenon groove of gas turbine stator blade rings presents complex technical challenges. The geometric features of the tenon groove structure are complex and varied, making it difficult for traditional measurement methods to accurately capture its critical dimensions, resulting in insufficient measurement accuracy. Furthermore, the irregular shapes of the working and bottom surfaces of the tenon groove complicate data collection and processing. Furthermore, low inspection efficiency for large numbers of tenon grooves in mass production severely constrains production schedules. These intertwined issues create a thorny technical dilemma: how to achieve rapid, mass-produced measurement of complex geometric features while ensuring high precision. This dilemma directly impacts the overall performance and reliability of gas turbines. Addressing this challenge requires overcoming the limitations of traditional measurement technology and innovating measurement methods and data processing algorithms. Furthermore, considerations must be given to establishing an optimized coordinate system and effectively deconstructing the geometric features of the tenon groove to facilitate precise positioning and measurement of critical dimensions. Furthermore, improving mass inspection efficiency while maintaining measurement accuracy are pressing technical challenges. These sub-problems, all centered around this central dilemma, collectively constitute the core technical challenge for precision measurement of the outer ring tenon groove of gas turbine stator blade rings. Summary of the Invention

[0003] The purpose of the present invention is to provide a three-coordinate detection and evaluation method for the dovetail groove of the outer ring of the gas turbine stator ring, which can be independent of special measuring tools and the assistance of multiple people, and can quickly complete the detection of the outer ring groove in an efficient, quantitative and accurate manner.

[0004] A three-coordinate detection and evaluation method for a dovetail groove of a gas turbine stator ring outer ring comprises the following steps:

[0005] S1, obtain the outer ring and place it on the three-coordinate platform;

[0006] S2, import the digital model and collect the outer ring datum elements to establish the coordinate system according to the design datum requirements;

[0007] S3, deconstructing the dimensional elements of the outer ring mortise and tenon;

[0008] S4, using a three-coordinate measuring probe to collect geometric features in the mortise and tenon and construct dimensional elements, and judging whether they meet the requirements based on the tolerance threshold.

[0009] Furthermore, the step S2 imports the digital model and collects the outer ring reference elements according to the design reference requirements to establish a coordinate system, including:

[0010] S2.1. Collect three evenly distributed vector points on the outer ring digital model reference plane to construct a plane. Collect three evenly distributed vector points on the outer circle of the outer ring digital model to construct a circle. Determine that the plane is the coordinate system Z zero point with the positive Z axis perpendicular to the plane, and the outer circle is the origin of the coordinate system X and Y axes. Establish an initial coordinate system so that the outer ring coordinate system is consistent with the digital model coordinate system.

[0011] S2.2, adjust the stylus angle, evenly collect six points on each of the two working surfaces of the outer ring tenon groove, obtain twelve points of the above-mentioned plane, outer circle and two working surfaces, use the best fit method of 3D rotation and least squares to establish the coordinate system, and determine that the best fit tolerance is the minimum tolerance of the drawing.

[0012] Furthermore, the dimensional elements of the outer ring mortise and tenon groove deconstructed in S3 include:

[0013] The mortise angle is determined to be the inclination angle of the mortise relative to the axis of the outer ring, the mortise N value is determined to be the positioning dimension of the mortise along the circumference, the mortise center distance is determined to be the distance between the bottom surface of the mortise and the center of the outer ring, the mortise offset distance is determined to be the distance between the center of the mortise and the plane of the outer ring, and the mortise uniform distribution is determined to be the position degree of each mortise.

[0014] Furthermore, in S4, the geometric features of the mortise and tenon groove are collected by a three-coordinate measuring probe and dimensional elements are constructed, including:

[0015] Points are taken on the outer ring plane to construct plane Q. A three-coordinate probe is used to take points on the two working surfaces of the mortise and tenon to construct the left surface L and the right surface R. The measured mid-plane M of the left surface L and the right surface R is constructed. A three-coordinate probe is used to take points on the bottom surface of the mortise and tenon to construct the bottom surface D of the mortise and tenon.

[0016] Furthermore, the dimensional elements of the deconstructed outer ring mortise and tenon groove include:

[0017] The mortise angle is determined by evaluating the 3D angle between the measured midpoint plane M and the Z axis. The mortise N value is determined by evaluating the coordinate positions of the corner points P of the mortise bottom surface D, the midpoint plane M of the two working surfaces of the mortise, and the outer ring plane Q. The mortise center distance is determined by evaluating the normal position coordinates of the groove bottom surface on the coordinate axis.

[0018] Furthermore, the dimensional elements of the deconstructed outer ring mortise and tenon groove include:

[0019] The offset distance of the mortise and tenon is determined by evaluating the distance between the corner point P1 of the median plane M of the two working surfaces of the mortise and tenon, the bottom surface D of the mortise and tenon, and the median vertical plane C of the outer ring and the outer ring plane Q. By selecting any point on the working surface of the digital model mortise and tenon and making the number of the array in the coordinate system X0Y0 the same as that of the mortise and tenon, the digital model array points are automatically collected, and the outer circle of the outer ring is used as the reference to evaluate the measured points and the theoretical position of the digital model to determine the uniform distribution of the mortise and tenon.

[0020] The beneficial effects of the present invention are as follows: the present invention discloses a method for the precise measurement of the outer ring tenon groove of the stator ring of a gas turbine. This method targets the complex geometric features of the outer ring tenon groove, and through three-coordinate measurement technology and data processing algorithms, achieves high-precision measurement of the key dimensions of the tenon groove. The present invention first establishes an optimized coordinate system, then deconstructs the geometric features of the tenon groove, and determines the set of dimensional elements to be measured. By collecting working surface and bottom surface data, the actual geometric features are constructed, and the coordinates of the key points are determined in combination with the reference plane. For each dimensional element, the corresponding geometric feature data is used for calculation, the measurement value is obtained, and the tolerance judgment is performed. The present invention also uses a three-coordinate turntable to realize batch detection, which greatly improves the measurement efficiency. This method significantly improves the measurement accuracy and efficiency of the outer ring tenon groove of the stator ring of a gas turbine, and provides a reliable guarantee for product quality control. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a three-dimensional diagram of the present invention;

[0022] Figure 2 Schematic diagram A of the mortise and tenon detection of the present invention;

[0023] Figure 3 Schematic diagram B of the mortise and tenon detection of the present invention;

[0024] Figure 4 Schematic diagram C of the mortise and tenon detection of the present invention. DETAILED DESCRIPTION

[0025] The present invention will be further described below with reference to the accompanying drawings.

[0026] like Figure 1-Figure 4 As shown, a method for detecting and evaluating the dovetail groove of the outer ring of a gas turbine stator ring specifically includes:

[0027] S1, obtain the outer ring of the gas turbine stator ring, which has multiple dovetail-shaped tenons. Place the outer ring on the three-dimensional coordinate measurement platform, and ensure that the position of any tenon is consistent with the negative direction of the Y axis of the measuring machine.

[0028] S2, import the outer ring digital model, and according to the design benchmark requirements, use a three-coordinate measuring probe to collect the vector points of the outer ring reference plane and outer circle to construct the initial coordinate system, which is consistent with the digital model coordinate system.

[0029] Import the outer ring digital model data to obtain the design benchmark requirement information. According to the design benchmark requirements, collect three vector points of the outer ring reference plane and construct the reference plane. Construct the outer circle geometric features by collecting three vector points of the outer ring outer circle. Use the reference plane to determine the coordinate system Z zero, and set the Z positive axis perpendicular to the plane. Determine the origin of the coordinate system X and Y axes based on the outer circle geometric features to generate the initial coordinate system. Obtain the initial coordinate system data, adjust the probe angle, and collect six points on each of the two working surfaces of the outer ring tenon. Using the 12 points collected on the reference plane, outer circle, and tenon working surface, apply 3D rotation and least squares fitting to construct the optimal coordinate system. Modify the best fit tolerance according to the minimum tolerance requirements of the drawing to obtain the optimized coordinate system. Determine the consistency of the optimized coordinate system with the digital model coordinate system to obtain the final coordinate system data.

[0030] S3, deconstructing the geometric features of the mortise and tenon, and determining a set of dimension elements that need to be measured, wherein the set of dimension elements includes mortise and tenon angle, positioning dimension, center distance, offset distance and position accuracy.

[0031] S3.1, mortise angle α: the inclination angle of the mortise relative to the axis of the outer ring;

[0032] Detection method: Evaluate the 3D angle between the measured midpoint plane M and the Z axis.

[0033] S3.2, mortise and tenon N value, the positioning dimension of the mortise and tenon along the circumference of the wheel disc;

[0034] Detection method: Evaluate the coordinate positions of the corner points P of the bottom surface D of the mortise and tenon groove, the midpoint M between the two working surfaces of the mortise and tenon groove, and the outer ring plane Q.

[0035] S3.3, Mortise center distance A: the distance between the bottom surface of the mortise groove and the center of the outer ring;

[0036] Detection method: Evaluate the normal position coordinates of the groove bottom surface on the coordinate axis.

[0037] S3.4, mortise offset distance L: the distance between the mortise center point P1 and the outer ring plane Q;

[0038] Detection method: Evaluate the distance between the corner point P1 of the three surfaces, the midpoint plane M of the two working surfaces of the mortise and tenon, the bottom surface D of the mortise and tenon, and the median vertical plane C of the outer ring, and the outer ring plane Q.

[0039] S3.5. Mortise and tenon uniformity T: Position of each mortise and tenon.

[0040] Detection method: Select any point on the working surface of the digital model mortise and tenon, place this point in the X0Y0 array of the coordinate system with the same number as the mortise and tenon, automatically collect the digital model array points on the part, and use the outer circle of the outer ring as the reference to evaluate the position accuracy between the measured point and the digital model theory.

[0041] In step S4, the three-dimensional probe collects the geometric features in the mortise and tenon, constructs the corresponding dimensional elements for evaluation, and determines whether it meets the drawing requirements based on the drawing tolerance threshold;

[0042] S4.1. Three coordinates are collected on the outer ring plane to construct plane Q.

[0043] S4.2. Use a three-dimensional coordinate probe to sample points on the two working surfaces of the mortise and tenon to construct the left surface L and the right surface R;

[0044] S4.3. Construct the measured median plane M of the left side L and the right side R;

[0045] S4.4. Use a three-dimensional probe to sample points on the bottom surface of the mortise and tenon groove and construct the groove bottom surface D;

[0046] S4.5. Use the three-coordinate rotary table to set the single mortise and tenon index value. The stylus can measure all mortises at the same position.

[0047] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A three-coordinate detection and evaluation method for the dovetail groove of the outer ring of a gas turbine stator ring, characterized in that: The following steps are involved: S1, obtain the outer ring and place it on the three-coordinate platform; S2, import the digital model and collect the outer ring datum elements to establish the coordinate system according to the design datum requirements; S3, deconstructing the dimensional elements of the outer ring mortise and tenon; S4, using a three-coordinate measuring probe to collect geometric features in the mortise and tenon and construct dimensional elements, and judging whether they meet the requirements based on the tolerance threshold.

2. A three-coordinate detection and evaluation method for the dovetail groove of the outer ring of a gas turbine stator blade ring according to claim 1, characterized in that: In said S2, the digital model is imported and the outer ring reference elements are collected according to the design reference requirements to establish a coordinate system, including: S2.

1. Collect three evenly distributed vector points on the outer ring digital model reference plane to construct a plane. Collect three evenly distributed vector points on the outer circle of the outer ring digital model to construct a circle. Determine that the plane is the coordinate system Z zero point with the positive Z axis perpendicular to the plane, and the outer circle is the origin of the coordinate system X and Y axes. Establish an initial coordinate system so that the outer ring coordinate system is consistent with the digital model coordinate system. S2.2, adjust the stylus angle, evenly collect six points on each of the two working surfaces of the outer ring tenon groove, obtain twelve points of the above-mentioned plane, outer circle and two working surfaces, use the best fit method of 3D rotation and least squares to establish the coordinate system, and determine that the best fit tolerance is the minimum tolerance of the drawing.

3. A three-coordinate detection and evaluation method for the dovetail groove of the outer ring of a gas turbine stator blade ring according to claim 1, characterized in that: The dimensional elements of the outer ring mortise and tenon groove deconstructed in S3 include: The mortise angle is determined to be the inclination angle of the mortise relative to the axis of the outer ring, the mortise N value is determined to be the positioning dimension of the mortise along the circumference, the mortise center distance is determined to be the distance between the bottom surface of the mortise and the center of the outer ring, the mortise offset distance is determined to be the distance between the center of the mortise and the plane of the outer ring, and the mortise uniform distribution is determined to be the position degree of each mortise.

4. A three-coordinate detection and evaluation method for the dovetail groove of the outer ring of a gas turbine stator blade ring according to claim 1, characterized in that: In S4, the geometric features in the mortise and tenon groove are collected by a three-coordinate measuring probe and dimensional elements are constructed, including: Points are taken on the outer ring plane to construct plane Q. A three-coordinate probe is used to take points on the two working surfaces of the mortise and tenon to construct the left surface L and the right surface R. The measured mid-plane M of the left surface L and the right surface R is constructed. A three-coordinate probe is used to take points on the bottom surface of the mortise and tenon to construct the bottom surface D of the mortise and tenon.

5. A three-coordinate detection and evaluation method for the dovetail groove of the outer ring of a gas turbine stator blade ring according to claim 3, characterized in that: The dimensional elements of the deconstructed outer ring mortise and tenon groove include: The mortise angle is determined by evaluating the 3D angle between the measured midpoint plane M and the Z axis. The mortise N value is determined by evaluating the coordinate positions of the corner points P of the mortise bottom surface D, the midpoint plane M of the two working surfaces of the mortise, and the outer ring plane Q. The mortise center distance is determined by evaluating the normal position coordinates of the groove bottom surface on the coordinate axis.

6. A three-coordinate detection and evaluation method for the dovetail groove of the outer ring of a gas turbine stator blade ring according to claim 5, characterized in that: The dimensional elements of the deconstructed outer ring mortise and tenon groove include: The offset distance of the mortise and tenon is determined by evaluating the distance between the corner point P1 of the median plane M of the two working surfaces of the mortise and tenon, the bottom surface D of the mortise and tenon, and the median vertical plane C of the outer ring and the outer ring plane Q. By selecting any point on the working surface of the digital model mortise and tenon and making the number of the array in the coordinate system X0Y0 the same as that of the mortise and tenon, the digital model array points are automatically collected, and the outer circle of the outer ring is used as the reference to evaluate the measured points and the theoretical position of the digital model to determine the uniform distribution of the mortise and tenon.

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