A method of forming a gas turbine turbine blade positioning tool
By using 3D reverse engineering and 3D printing technology to manufacture turbine blade positioning fixtures, the problems of low precision and large individual differences in existing fixtures have been solved. This has enabled high-precision and stable blade positioning and cutting benchmarks, thereby improving production efficiency and product quality.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- XIAN THERMAL POWER RES INST CO LTD
- Filing Date
- 2023-05-15
- Publication Date
- 2026-07-21
AI Technical Summary
Existing turbine blade positioning fixtures have low precision and large individual differences, resulting in low production efficiency, high cost, and inconsistent cutting benchmarks, making it difficult to accurately evaluate the microstructure and mechanical properties of the blades.
The tenon data is obtained by using three-dimensional reverse measurement technology, and the three-dimensional models of the positioning base and locking device are designed. The positioning fixture is manufactured using 3D printing technology, including the precise combination of the positioning base and locking device. The fixture is printed by a selective laser melting system and post-processed to ensure positioning accuracy and stability.
This improved the accuracy and consistency of the positioning fixtures, ensuring that the cutting reference of the blades was consistent across different fixtures, thereby enhancing mass production efficiency and product quality.
Smart Images
Figure CN116571760B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of positioning tooling technology, and specifically to a method for forming a positioning tooling for gas turbine blades. Background Technology
[0002] Turbine blades, as core hot-end components of gas turbines, are characterized by their large size and mass, harsh high-temperature service environment, long overhaul cycles, and long overall lifespan. Turbine blades mainly consist of two parts: the blade body and the tenon. The blade body has a complex profile, containing numerous free-form surfaces. The tenon bears various working loads of the blade and primarily uses a fir tree tenon structure. The pitch, transition radius, tenon width wedge angle, pressure angle, and tooth profile angle of the fir tree tenon undergo complex design and software verification before leaving the factory. To evaluate the quality of the turbine blade's metallurgical and heat treatment before service, and to analyze damage and failure after service, it is necessary to position, clamp, and dissect the turbine blade for subsequent microstructure and mechanical property testing. When clamping the blade tenon using positioning fixtures, the traditional casting method of molding, pouring, cooling, and demolding the blade tenon is often used because the three-dimensional structural parameters of the blade cannot be obtained. This method is not only inefficient but also costly. When mass-producing turbine blade positioning fixtures, traditional machining methods require the use of multiple pieces of equipment. Changing equipment can easily cause the positioning fixtures to lose their machining reference. There are large individual differences between different positioning fixtures, resulting in low processing efficiency and yield. Moreover, when using turbine blade positioning fixtures to clamp and cut blades, the differences in positioning fixtures can also cause significant differences in the stability of clamped blades. This makes it impossible to accurately calibrate the cutting reference of the same type of blade when cutting blades, which can easily lead to difficulties in corresponding and comparing the microstructure and mechanical properties of blades of the same specification. As a result, it is impossible to accurately evaluate the microstructure and mechanical properties of turbine blades. Summary of the Invention
[0003] Therefore, the technical problem to be solved by the present invention is to overcome the defects of low precision and large individual differences in the turbine blade positioning fixtures produced in the prior art, thereby providing a forming method for gas turbine blade positioning fixtures.
[0004] To solve the above-mentioned technical problems, the present invention provides a forming method for a gas turbine blade positioning fixture. The gas turbine blade positioning fixture includes: a positioning base and a positioning locker. A positioning locker groove is provided through the positioning base. A gas turbine blade installation position is provided at one end of the positioning locker groove. A limiting part is provided at the installation position. The limiting part matches the external shape of the tenon of the gas turbine blade and is suitable for clamping and limiting the tenon. The positioning locker is installed in the positioning locker groove. At least one clamping member is provided at one end of the locking member. The clamping member is suitable for engaging with the air inlet at the tail of the tenon to lock and fix it.
[0005] The molding method includes the following steps:
[0006] Three-dimensional reverse measurement of the blade tenon is performed to obtain the three-dimensional shape data file of the blade tenon;
[0007] The blade positioning base is designed in the forward direction. The three-dimensional shape data file of the blade tenon is used to generate the three-dimensional data of the installation station, and the three-dimensional data model of the positioning base with the installation station is drawn. At the same time, the three-dimensional data model of the positioning lock is drawn.
[0008] 3D printing of blade positioning fixtures involves importing the 3D data models of the positioning base and the positioning locker into the printer software for metal 3D printing.
[0009] Post-processing of blade positioning fixtures to obtain gas turbine blade positioning fixture products.
[0010] Optionally, the three-dimensional reverse measurement of the blade tenon includes: measuring the three-dimensional coordinate points on the tenon surface, processing the three-dimensional coordinate point data to perform three-dimensional reconstruction of the blade tenon, and outputting the three-dimensional data model of the blade tenon.
[0011] Optionally, the step of measuring the three-dimensional coordinates of the tenon surface includes:
[0012] Open the 3D scanner for calibration and establish a scanning baseline;
[0013] A continuous 3D scan of the blade tenon is performed at an angle of 30° to 60°. After scanning around the tenon once, a 3D point cloud image and 3D point cloud data of the tenon are obtained and saved.
[0014] Optionally, after the step of drawing the three-dimensional data model of the positioning lock, the following steps are also included:
[0015] The three-dimensional data models of the positioning fixture and the positioning locking device are divided, selected, loaded, and solved into element meshes.
[0016] Determine the stress concentration points of the positioning base and optimize and strengthen these stress concentration points.
[0017] The optimized positioning base and positioning lock were designed for assembly dimensions, process dimensions, and allowances to obtain the final three-dimensional data model of the positioning fixture.
[0018] Optionally, the steps of importing the 3D data models of the positioning base and the positioning lock into the printer software for metal 3D printing include:
[0019] Import the 3D data model of the positioning fixture and the 3D data model of the positioning locker into the printer software and generate supports and model slices for the positioning fixture.
[0020] The sliced model file is imported into the selective laser melting system control host, and metal 3D printing is performed within the selective laser melting system control host;
[0021] Optionally, the metal 3D printing steps include:
[0022] A substrate is installed on the worktable of the forming cavity of the control host of the selective laser melting system;
[0023] After sealing the molding cavity, the molding cavity is evacuated, then an inert protective gas is introduced, and the process parameters are entered.
[0024] Three-dimensional solid models of the positioning base and the positioning lock were printed on the mounting base of the molding cavity.
[0025] Optionally, the process parameters include: input power 290W, spot diameter 65μm, printing speed 850mm / s, processing layer thickness 0.05mm, scanning method using line outline outlining plus internal straight line scanning, and scanning interval 0.01mm. Metal powder is repeatedly fed into the tooling for forming, with a printing allowance set to 0.15mm.
[0026] Optionally, in the metal 3D printing step, the metal powder has a particle size distribution of 15–55 μm and a loose packing density of 4.0 g / cm³. 3 Hall flow rate is 16s / 50g, D 50 304 stainless steel with a particle size distribution of 35.0% and an oxygen content maintained below 800-900 ppm.
[0027] Optionally, post-processing includes: importing the 3D data model of the positioning base and the 3D data model of the positioning lock into the machine tool software, planning the cutting path after unifying the coordinate system, and removing the printing allowance from the 3D solid model of the positioning base and the 3D solid model of the positioning lock containing the mounting plate.
[0028] Optionally, the post-processing also includes: removing the base plate and support of each component of the positioning fixture, and after removal, grinding and polishing the surface of each component of the positioning fixture, and cleaning and drying the surface.
[0029] The technical solution of this invention has the following advantages:
[0030] 1. The forming method of the gas turbine blade positioning fixture provided by the present invention includes the following steps: three-dimensional reverse measurement of the blade tenon to obtain the three-dimensional shape data file of the blade tenon; forward design of the blade positioning base, using the three-dimensional shape data file of the blade tenon to generate the three-dimensional data of the installation station, and drawing the three-dimensional data model of the positioning base with the installation station, and simultaneously drawing the three-dimensional data model of the positioning lock; 3D printing of the blade positioning fixture, importing the three-dimensional data model of the positioning base and the three-dimensional data model of the positioning lock into the printer software for metal 3D printing; post-processing of the blade positioning fixture to obtain the gas turbine blade positioning fixture product.
[0031] When forming a positioning fixture for gas turbine blades, the tenon of the turbine blade is scanned, and the 3D data of the tenon on the turbine blade is used to generate 3D data of the mounting position on the positioning base and create a model. Based on the acquired data model, a solid model is printed, resulting in the gas turbine blade positioning fixture product. The obtained positioning fixture has high precision and minimal individual variation. Using the forming method of the gas turbine blade positioning fixture provided by this invention to clamp and fix the blade ensures that the cutting datum of the same type of blade installed on different positioning fixtures is consistent during blade cutting, thereby improving the production efficiency and product quality of subsequent mass production of the turbine blade positioning fixture.
[0032] 2. The forming method for the gas turbine blade positioning fixture provided by this invention includes the following steps for measuring the three-dimensional coordinate points of the tenon surface: calibrating a 3D scanner to establish a scanning reference; performing continuous 3D scanning of the blade tenon at an angle of 30° to 60°, scanning around the tenon to obtain a 3D point cloud image and data of the tenon, and saving the 3D point cloud image and data. Scanning the tenon structure with a 3D scanner allows for accurate acquisition of the actual external structure of the tenon, thereby improving the fitting accuracy between the mounting position on the generated positioning base and the tenon, and enhancing the stability of the blade clamped and fixed on the positioning fixture.
[0033] 3. The forming method for the gas turbine blade positioning fixture provided by this invention, after the step of drawing the three-dimensional data model of the positioning lock, further includes: dividing, selecting, loading, and solving the three-dimensional data models of the positioning fixture and the positioning lock; determining the stress concentration location of the positioning base and optimizing and strengthening the stress concentration location; and performing assembly dimension design, process dimension design, and margin analysis on the optimized positioning base and positioning lock to obtain the final three-dimensional data model of the positioning fixture. Since there are significant differences in mass and size between blades of different specifications, loading and solving are necessary. The positioning fixture is formed according to the data of different blade specifications to ensure that each positioning fixture fits perfectly with the corresponding blade specification, improving the stability of the positioning fixture in clamping the blade. Attached Figure Description
[0034] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0035] Figure 1 A flowchart illustrating the forming method of the gas turbine blade positioning fixture provided in a specific embodiment of the present invention;
[0036] Figure 2 This is a schematic diagram of the gas turbine blade positioning fixture provided in a specific embodiment of the present invention.
[0037] Explanation of reference numerals in the attached diagram: 1. Positioning base; 2. Positioning lock; 3. Fixing bolt. Detailed Implementation
[0038] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0039] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for 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. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0040] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" 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 invention based on the specific circumstances.
[0041] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.
[0042] Figure 1 The image shows a method for forming a positioning fixture for a gas turbine blade provided in this embodiment. Figure 2 The gas turbine blade positioning fixture shown includes: a positioning base 1 and a positioning locker 2. The positioning base 1 has a through-hole positioning lock groove, and one end of the positioning lock groove has a gas turbine blade installation position. The installation position has a limiting part that matches the external shape of the tenon of the gas turbine blade, and the limiting part is suitable for locking and limiting the tenon. The positioning locker 2 is installed in the positioning lock groove, and one end of it has at least one clamping member, which is suitable for engaging with the air inlet at the tail of the tenon to lock and fix it. Mounting plates are provided on both sides of the positioning base 1, and the mounting plates have threaded holes. Fixing bolts 3 engage with the threaded holes to fix the positioning base 1 in place.
[0043] The forming method includes the following steps: 3D reverse modeling of the blade tenon, forward design of the blade positioning base, 3D printing of the blade positioning fixture, and post-processing of the blade positioning fixture. Specifically, the 3D reverse modeling of the blade tenon includes: 3D data measurement, 3D data processing, 3D reconstruction, and 3D model data output; the forward design of the blade positioning base includes: 3D structural design of the positioning fixture, finite element analysis, structural optimization, engineering drawing design, and dimensional chain analysis; the 3D printing of the blade positioning fixture includes: 3D model file conversion, generating a support for the positioning fixture, slicing it, importing it into the Selective Laser Melting (SLM) system control host, installing the substrate on the worktable of the forming cavity, sealing the forming cavity and evacuating it, introducing inert protective gas, inputting process parameters, and repeatedly feeding metal powder into the fixture for forming; the post-processing of the blade positioning fixture includes: heat treatment of the positioning fixture, importing the 3D model into the software and planning the cutting path, precision machining of the positioning fixture containing the substrate, removing the substrate and support, and surface cleaning and drying. The specific steps are as follows:
[0044] The 3D reverse modeling of the blade tenon uses a 3D laser scanner to measure the 3D coordinate points on the tenon surface. Because some tenons on the blade tenon are deeply recessed, a contrast-enhancing agent is sprayed onto the surface of the tenon, ensuring a thin and even spray. The 3D scanner is calibrated to establish a scanning baseline. A continuous 3D scan of the blade tenon is performed at an angle ranging from 30° to 60° (45° in this embodiment). After scanning around the tenon once, the 3D point cloud image and 3D point cloud data of the tenon are obtained and saved in STL format. Through 3D reverse modeling of the blade tenon, the 3D coordinate points on the tenon surface are quickly measured. After processing the 3D data, the 3D reconstruction of the blade tenon is performed, and the 3D data model of the blade tenon is output.
[0045] The measured 3D point cloud data of the blade tenon was processed to obtain the 3D coordinate data of the installation station. Based on the 3D coordinate data of the installation station, a 3D data model of the positioning base was drawn, along with 3D data models of the positioning lock and fixing bolts. Finite element analysis was then performed on the blade positioning fixture. This mainly included the generation, selection, loading, and solving of element meshes for each component of the blade positioning fixture. Due to the significant differences in mass and size among different blades, loading and solving were necessary. The stress concentration locations on the positioning base were identified, and the structural optimization design of the blade positioning fixture was performed. Subsequently, engineering drawing design and dimensional chain analysis were conducted on the optimized blade positioning fixture, mainly including the design of the assembly dimensions and process dimensions of the positioning fixture and the analysis of allowances. The final fixture drawing of the blade positioning fixture was determined and saved in STL format.
[0046] The 3D models of different components of the turbine blade positioning fixture were imported into the printer software, and supports and model slices were generated for the positioning fixture. The sliced STL files were then imported into the SLM system control host. A substrate made of nickel-chromium alloy was installed on the worktable of the forming cavity. After sealing the forming cavity, it was evacuated, and an inert protective gas was introduced into the equipment, along with the process parameters. Argon was selected as the inert protective gas for selective laser melting printing. The main process parameters included: input power 290W, spot diameter 65μm, printing speed 850mm / s, processing layer thickness 0.05mm, scanning method using line contour outlining plus internal straight line scanning, scanning interval 0.01mm, repeated feeding of metal powder into the fixture, printing allowance set to 0.15mm, and metal powder with a particle size distribution of 15-55μm and a loose packing density of 4.0g / cm³. 3 Hall flow rate is 16s / 50g, D 50 304 stainless steel with a particle size distribution of 35.0% and an oxygen content maintained below 800-900 ppm.
[0047] After printing, the various components of the positioning fixture undergo post-processing. The STL 3D model of the positioning fixture is imported into the machine tool software, and the cutting path is planned after unifying the coordinate system. The printing allowance of the positioning fixture, including the mounting base plate, is removed, and then precision machining is performed. After precision machining, the base plate and support of each component of the positioning fixture are removed. After removal, the surface of the removed area is ground and polished, and then cleaned and dried.
[0048] In the process of forming a positioning fixture for gas turbine blades, the tenon of the turbine blade is scanned, and the three-dimensional data of the tenon on the turbine blade is used to generate three-dimensional data of the installation position on the positioning base and create a model. Based on the acquired data model, a solid model is printed, thus obtaining the gas turbine blade positioning fixture product. The resulting positioning fixture has high precision and minimal individual variation. Using the forming method of the gas turbine blade positioning fixture provided by this invention to clamp and fix the blade ensures that the cutting datum of the same type of blade installed on different positioning fixtures is consistent during blade cutting.
[0049] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.
Claims
1. A method for forming a positioning fixture for gas turbine blades, characterized in that, The gas turbine blade positioning fixture includes: a positioning base and a positioning locker. A positioning locker groove is provided through the positioning base. One end of the positioning locker groove is provided with a gas turbine blade installation position. A limiting part is provided on the installation position. The limiting part matches the external shape of the tenon of the gas turbine blade. The limiting part is suitable for clamping and limiting the tenon. The positioning locker is installed in the positioning locker groove. One end of the locking locker is provided with at least one clamping member. The clamping member is suitable for engaging with the air inlet at the tail of the tenon to lock and fix it. The molding method includes the following steps: Three-dimensional reverse measurement of the blade tenon is performed to obtain the three-dimensional shape data file of the blade tenon; The blade positioning base is designed in the forward direction. The three-dimensional shape data file of the blade tenon is used to generate the three-dimensional data of the installation station, and the three-dimensional data model of the positioning base with the installation station is drawn. At the same time, the three-dimensional data model of the positioning lock is drawn. 3D printing of blade positioning fixtures involves importing the 3D data models of the positioning base and the positioning locker into the printer software for metal 3D printing. Post-processing of blade positioning fixtures to obtain gas turbine blade positioning fixture products; After the step of drawing the three-dimensional data model of the positioning lock, the method further includes: The three-dimensional data models of the positioning fixture and the positioning locking device are divided, selected, loaded, and solved into element meshes. Determine the stress concentration points of the positioning base and optimize and strengthen these stress concentration points. The optimized positioning base and positioning lock are designed for assembly dimensions, process dimensions, and allowances to obtain the final three-dimensional data model of the positioning fixture. In the metal 3D printing step, the metal powder has a particle size distribution of 15~55µm and a loose packing density of 4.0g / cm³. 3 Hall flow rate is 16s / 50g, D 50 304 stainless steel with a particle size distribution of 35.0% and an oxygen content maintained below 800~900ppm.
2. The forming method of the gas turbine blade positioning fixture according to claim 1, characterized in that, The three-dimensional reverse measurement of the blade tenon includes: measuring the three-dimensional coordinate points on the tenon surface, processing the three-dimensional coordinate point data to perform three-dimensional reconstruction of the blade tenon, and outputting the three-dimensional data model of the blade tenon.
3. The forming method of the gas turbine blade positioning fixture according to claim 2, characterized in that, The step of measuring the three-dimensional coordinate points of the tenon surface includes: Open the 3D scanner for calibration and establish a scanning baseline; A continuous 3D scan of the blade tenon is performed at an angle of 30° to 60°. After scanning around the tenon once, a 3D point cloud image and 3D point cloud data of the tenon are obtained and saved.
4. The forming method of the gas turbine blade positioning fixture according to any one of claims 1 to 3, characterized in that, The steps for importing the 3D data models of the positioning base and the positioning lock into the printer software for metal 3D printing include: Import the 3D data model of the positioning fixture and the 3D data model of the positioning locker into the printer software and generate supports and model slices for the positioning fixture. The sliced model file is imported into the selective laser melting system control host, and metal 3D printing is performed within the selective laser melting system control host.
5. The forming method of the gas turbine blade positioning fixture according to claim 4, characterized in that, The metal 3D printing steps include: A substrate is installed on the worktable of the forming cavity of the control host of the selective laser melting system; After sealing the molding cavity, the molding cavity is evacuated, then an inert protective gas is introduced, and the process parameters are entered. Three-dimensional solid models of the positioning base and the positioning lock were printed on the mounting base of the molding cavity.
6. The forming method of the gas turbine blade positioning fixture according to claim 5, characterized in that, The process parameters include: input power 290W, spot diameter 65µm, printing speed 850mm / s, processing layer thickness 0.05mm, scanning method using line outline outlining plus internal straight line scanning, scanning interval 0.01mm; repeated feeding of metal powder to the tooling to form, and printing allowance set to 0.15mm.
7. The forming method of the gas turbine blade positioning fixture according to claim 6, characterized in that, The post-processing includes: importing the three-dimensional data model of the positioning base and the three-dimensional data model of the positioning lock into the machine tool software, planning the cutting path after unifying the coordinate system, and removing the printing allowance from the three-dimensional solid model of the positioning base and the three-dimensional solid model of the positioning lock containing the mounting base.
8. The forming method of the gas turbine blade positioning fixture according to claim 7, characterized in that, The post-processing also includes: removing the base plate and support of each component of the positioning fixture, and after removal, grinding and polishing the surface of each component of the positioning fixture, and cleaning and drying the surface.