CN-117020448-B - Protection device generation method and protection method for hollow blade processing air film hole

CN117020448BCN 117020448 BCN117020448 BCN 117020448BCN-117020448-B

Abstract

The invention relates to the technical field of aeroengines, and discloses a generation method and a protection method of a protection device for processing a gas film hole of a hollow blade, aiming at avoiding the damage of laser to an inner cavity when the hollow blade of the aeroengine is used for processing the gas film hole; marking the wall surface of an inner cavity to be protected in the three-dimensional model of the blade according to the position of the air film hole to be processed, generating a corresponding three-dimensional model of the protecting device according to the marked wall surface of the inner cavity, generating a corresponding protecting device according to the three-dimensional model of the protecting device, and placing the protecting device into the inner cavity from a cooling air flow inlet of the hollow blade and fixing the protecting device before the air film hole is processed by laser. The invention avoids damage to the wall caused by laser, improves the processing quality of the small hole outlet, improves the yield, quality and service life of the high-pressure turbine blade, and is particularly suitable for aeroengines.

Inventors

CHEN TAILI
ZHANG YOU
XU LIANGHUI
YE YONGSONG
LI SHUGUANG
HOU XIAOWEI
CHEN XINYUE
SUN JIANG
SUN ZHIGUO

Assignees

成都天翔动力技术研究院有限公司

Dates

Publication Date: 20260505
Application Date: 20230828

Claims (8)

1. The method for generating the protecting device for processing the air film hole of the hollow blade is characterized by comprising the following steps of: Determining a blade three-dimensional model corresponding to the hollow blade to be processed; Marking an inner cavity wall surface to be protected in the three-dimensional blade model according to the position of the air film hole to be processed, wherein the marked inner cavity wall surface at least comprises an inner cavity reinforcing rib structure, a supporting bulge structure and a blade section outlet form; generating a corresponding three-dimensional model of the protecting device according to the marked inner cavity wall surface, and generating a corresponding protecting device according to the three-dimensional model of the protecting device; generating a corresponding three-dimensional model of the protective device according to the marked inner cavity wall surface, which specifically comprises the following steps: measuring the normal thickness of each inner cavity reinforcing rib structure and each supporting bulge structure respectively, determining the maximum normal thickness, deleting the inner cavity reinforcing rib structures and the supporting bulge structures in the three-dimensional model of the blade after the completion, and only keeping the basic geometric model of the inner cavity; In the basic geometric model, respectively extracting edge profile curves of two end surfaces of an inner cavity, respectively carrying out normal offset inwards on the edge profile curves of the two end surfaces, and determining the offset distance according to the maximum normal thickness; And taking the edge profile curve of the inner cavity with the offset two end surfaces as a boundary curve of the protective device, and establishing a complete three-dimensional model of the protective device based on the boundary curve.
2. The method for producing a protective device for processing air film holes of hollow blades according to claim 1, wherein the offset distance is a sum of a maximum normal thickness and a preset thickness, and the preset thickness is 0.3-0.8 mm.
3. The method of generating a guard for a hollow vane machining gas film hole as claimed in claim 1, wherein the method of generating a corresponding guard from the guard three-dimensional model comprises: the guard is manufactured according to a three-dimensional model of the guard and using a molding method, such as casting, 3D printing or machining.
4. The method of claim 3, wherein the protective device is made of a material with laser damage resistance, and the material with laser damage resistance comprises one or more of steel, aluminum alloy, titanium alloy, superalloy, ceramic, graphite and paraffin.
5. The protection method for processing the air film hole by the hollow blade is characterized by comprising the following steps of: Determining a blade three-dimensional model corresponding to the hollow blade to be processed; Marking an inner cavity wall surface to be protected in the three-dimensional blade model according to the position of the air film hole to be processed, wherein the marked inner cavity wall surface at least comprises an inner cavity reinforcing rib structure, a supporting bulge structure and a blade section outlet form; generating a corresponding three-dimensional model of the protecting device according to the marked inner cavity wall surface, and generating a corresponding protecting device according to the three-dimensional model of the protecting device; before the laser is used for processing the air film hole, the protecting device is put into an inner cavity from a cooling air flow inlet of the hollow blade and fixed; generating a corresponding three-dimensional model of the protective device according to the marked inner cavity wall surface, which specifically comprises the following steps: measuring the normal thickness of each inner cavity reinforcing rib structure and each supporting bulge structure respectively, determining the maximum normal thickness, deleting the inner cavity reinforcing rib structures and the supporting bulge structures in the three-dimensional model of the blade after the completion, and only keeping the basic geometric model of the inner cavity; In the basic geometric model, respectively extracting edge profile curves of two end surfaces of an inner cavity, respectively carrying out normal offset inwards on the edge profile curves of the two end surfaces, and determining the offset distance according to the maximum normal thickness; And taking the edge profile curve of the inner cavity with the offset two end surfaces as a boundary curve of the protective device, and establishing a complete three-dimensional model of the protective device based on the boundary curve.
6. The method for protecting a hollow vane machining air film hole as defined in claim 5, wherein the offset distance is a sum of a maximum normal thickness and a preset thickness, and the preset thickness is 0.3-0.8 mm.
7. The method of claim 5, wherein the method of generating the corresponding guard according to the guard three-dimensional model comprises: the guard is manufactured according to a three-dimensional model of the guard and using a molding method, such as casting, 3D printing or machining.
8. The method of claim 7, wherein the protective device is made of a material resistant to laser damage, the material resistant to laser damage including one or more of steel, aluminum alloy, titanium alloy, superalloy, ceramic, graphite, and paraffin.

Description

Protection device generation method and protection method for hollow blade processing air film hole Technical Field The invention relates to the technical field of aeroengines, in particular to a method for generating a protecting device for processing a gas film hole of a hollow blade and a protecting method. Background When the aeroengine works, as one of hot end components, the high-pressure turbine guide vane bears high-temperature high-pressure gas impact, and on the premise of limited high-temperature resistance of alloy materials, in order to improve the inlet temperature of the turbine and ensure that the turbine can normally and reliably operate and work in a high-temperature service environment, the high-pressure turbine guide vane cooling technology becomes an effective way for solving the problem, and the gas film cooling holes can enable the high-pressure turbine guide vane made of the same materials to normally operate in a higher-temperature environment. The hollow blade air film hole has remarkable effect on the performance of the engine, can effectively improve the processing capacity and efficiency of the blade air film hole, and is one of important research contents in the field of aeroengines. The femtosecond laser processing technology becomes a new generation of leading edge key technology for solving the processing of the hollow blade air film hole by virtue of the characteristics of high processing precision, no heat affected zone, no material selection and the like. However, when the femtosecond laser is selected to process the blades of the high-pressure turbine guide and the like, the inner cavity of the blade of the high-pressure turbine guide is relatively close, so that wall damage occurs in the process of processing, the quality and the service life of the hollow blade of the high-pressure turbine are inevitably influenced, and the yield of the blade of the high-pressure turbine is greatly reduced. Application publication number CN106583949a discloses a method for on-line automatic determination of blade air film Kong Dachuan monitoring, which obtains wall protection in the processing process, namely continuous monitoring and automatic interpretation of the punching process are carried out by on-line third party software of "punching monitoring", "punching monitoring coordinates", so as to realize on-line automatic determination of single crystal high vortex hollow blade air film Kong Dachuan monitoring of an aeroengine. When the 'penetration monitoring' method is adopted for the high-pressure turbine guide vane maintenance piece, the appearance and the size of the outlet are difficult to ensure due to the uneven thickness in the penetration direction and the numerous small holes on the vane. According to experimental verification, when the wall-to-wall distance is less than about 10mm, laser damage to the wall position of the inner cavity is still possible. Disclosure of Invention The invention aims to solve the problem that laser damages to the inner cavity of a hollow blade in the process of machining a gas film hole in the prior art, and provides a method for generating a protective device for machining the gas film hole of the hollow blade and a protective method. The technical scheme adopted by the invention for solving the technical problems is as follows: in a first aspect, a method for generating a protection device for processing a gas film hole by using a hollow blade is provided, and the method comprises the following steps: Determining a blade three-dimensional model corresponding to the hollow blade to be processed; Marking an inner cavity wall surface to be protected in the three-dimensional blade model according to the position of the air film hole to be processed, wherein the marked inner cavity wall surface at least comprises an inner cavity reinforcing rib structure, a supporting bulge structure and a blade section outlet form; And generating a corresponding three-dimensional model of the protecting device according to the marked inner cavity wall surface, and generating a corresponding protecting device according to the three-dimensional model of the protecting device. Further, generating a corresponding three-dimensional model of the protective device according to the marked inner cavity wall surface, specifically comprising: measuring the normal thickness of each inner cavity reinforcing rib structure and each supporting bulge structure respectively, determining the maximum normal thickness, deleting the inner cavity reinforcing rib structures and the supporting bulge structures in the three-dimensional model of the blade after the completion, and only keeping the basic geometric model of the inner cavity; In the basic geometric model, respectively extracting edge profile curves of two end surfaces of an inner cavity, respectively carrying out normal offset inwards on the edge profile curves of the two end surfaces, and determining the offset distance acc