A method for detecting a nozzle ring vane shimming grind

Abstract

The application relates to the field of precision casting, and particularly discloses a nozzle ring blade patch polishing detection method, tail edge detection sample plates and chord length detection sample plates are prepared according to blade design sizes, the tail edge detection sample plates are aligned with the exhaust edges of the blades and are inserted, whether the tail edge detection sample plates are completely inserted into the exhaust edges of the blades is observed, if not, the tail edge detection sample plates are polished again according to the gap between the inner walls of the tail edge detection sample plates and the exhaust edges of the blades, the chord length detection sample plates are attached to the back sides of the blades, and the normal distance between the chord length detection sample plates and the end surfaces of the tail edge detection sample plates on the back sides of the blades is measured; in the application, the tail edge detection sample plates and the chord length detection sample plates are prepared according to the theoretical model profiles of the blades, are attached to the blades, and the distance between the two is used to judge whether the patch polishing of the exhaust edges of the blades is in place, the operation is simple and convenient, the polishing amount can be repeatedly corrected in the polishing process, the production efficiency is improved, the accuracy of the polishing amount is easy to control, and the waste product rate is reduced.

Description

Technical Field

[0001] This invention relates to the field of precision casting, specifically a method for testing the grinding and patching of nozzle ring blades. Background Technology

[0002] Nozzle ring (e.g.) Figure 1 The nozzle ring (as shown) is one of the important components used to adjust the airflow direction of a gas turbine. It requires high overall precision, as well as high precision in blade installation and casting. Existing nozzle rings are fixed to inner and outer fixing rings and manufactured through a single integral casting process. To obtain a high-precision nozzle ring during casting, highly complex casting techniques and specialized equipment are required.

[0003] The blades of the nozzle ring have small cross sections, with the thinnest part being only 0.6 mm. They are usually located at the exhaust edge of the blades. Due to factors such as solidification shrinkage and poor fluidity of the molten metal during cooling, defects such as incomplete filling, deformation, porosity, and cracks are very easy to occur during the casting solidification process, which makes casting very difficult.

[0004] Typically, we add a patch to the venting edge of the nozzle ring blade on the wax model of the casting. By increasing the thickness of the venting edge, we can increase the thickness of the filling cavity, compensate for solidification shrinkage, improve the solidification sequence, and reduce stress concentration, thereby solving the aforementioned defects. Then, during the post-casting processing, the patch on the venting edge is ground off to obtain a casting that meets the structural requirements.

[0005] In the casting process of nozzle rings, process additives are added to the venting edge of the nozzle ring blades to increase the thickness of the venting edge and address defects such as incomplete filling, deformation, porosity, and cracks. This is a common casting process. However, during post-machining grinding, it is difficult to measure the amount of grinding, especially the venting edge thickness and chord length of the blades. Too much or too little grinding will result in non-compliant venting edge thickness and chord length dimensions, or even scrap the casting due to excessive grinding in a single operation. Therefore, how to detect the amount of grinding during the grinding process is crucial, and how to measure it has become an urgent problem to be solved.

[0006] Currently, the thickness of the exhaust edge of the nozzle ring blade is typically measured using a coordinate measuring machine (CMM) and blue light scanning to verify the blade profile and related dimensions. Similarly, the chord length of the nozzle ring blade is usually measured using a CMM and blue light scanning to verify the blade cross-section. However, during the grinding process of the exhaust edge patch, the grinding amount needs to be repeatedly checked; otherwise, the thickness of the exhaust edge and the chord length after grinding cannot be guaranteed. Traditional measurement methods become particularly cumbersome, lacking specificity for this process, impacting production efficiency, and making it difficult to accurately control the grinding amount.

[0007] To address the aforementioned issues, this application proposes a method for detecting nozzle ring blade subsidy grinding. Summary of the Invention

[0008] To address the existing problems, this invention provides a method for detecting nozzle ring blade patch grinding, which can effectively solve the problems mentioned in the background art.

[0009] To solve the above problems, the present invention adopts the following technical solution:

[0010] A method for inspecting the grinding and repair of nozzle ring blades includes the following steps:

[0011] S1. Inspection preparation: Prepare trailing edge inspection templates and chord length inspection templates according to the blade design dimensions. The trailing edge inspection template is fitted to the exhaust edge contour of the blade, and the chord length inspection template is fitted from the back side of the blade to the intake edge contour of the blade.

[0012] S2. Exhaust edge grinding inspection: After grinding the exhaust edge of the blade to a certain extent, insert the trailing edge inspection template into the exhaust edge of the blade and observe whether the trailing edge inspection template is fully inserted into the exhaust edge of the blade. If it is not fully inserted, grind it again to a certain extent according to the gap between the inner wall of the trailing edge inspection template and the exhaust edge of the blade until the trailing edge inspection template is fully inserted into the exhaust edge of the blade and the inner wall of the trailing edge inspection template is in close contact with the exhaust edge of the blade without shaking.

[0013] S3. Blade chord length detection: After the blade exhaust edge is polished, the chord length detection template is attached to the back side of the blade, and the normal distance between the chord length detection template on the back side of the blade and the end face of the trailing edge detection template is measured. When the normal distance is 20mm, the patch polishing is qualified. If the normal distance is greater than 20mm, the blade chord length is too large, and the blade exhaust edge patch needs to be polished again.

[0014] As a further aspect of the present invention: in step S1, both the trailing edge detection template and the chord length detection template are prepared by photosensitive resin 3D printing or metal processing.

[0015] As a further embodiment of the present invention: in step S1, both the trailing edge detection template and the chord length detection template are provided with a positioning structure that fits against the outer ring of the nozzle ring on the side near the outer ring of the nozzle ring.

[0016] As a further embodiment of the present invention: the cross-section of the trailing edge detection template in step S1 is a U-shaped structure, which can wrap around the trailing edge of the blade exhaust edge, and the end face of the trailing edge detection template is 3-5 mm away from the trailing edge of the blade exhaust edge.

[0017] As a further embodiment of the present invention: in step S1, one end of the chord length detection template is provided with a bending structure, and the bending structure is attached to the air intake side of the blade and extends to the front side of the blade.

[0018] As a further embodiment of the present invention: in step S1, the distance between the trailing edge detection template and the chord length detection template and the inner ring of the nozzle ring is 4-6 mm.

[0019] As a further embodiment of the present invention: in step S1, the profile tolerance of the trailing edge detection template and the chord length detection template to the blade contact surface is -0.01mm to -0.04mm.

[0020] As a further aspect of the present invention: if the trailing edge detection template is not in contact with the blade exhaust edge after being fully inserted into the blade exhaust edge in step S2 and the trailing edge detection template can wiggle, it indicates that the grinding is excessive and difficult to repair, and it should be scrapped.

[0021] As a further aspect of the present invention: the tolerance of the normal distance in step S3 is ±0.01mm.

[0022] As a further aspect of the present invention: if the normal distance in step S3 is less than 20mm, it indicates that the trailing edge of the exhaust edge of the blade has been excessively ground and is difficult to repair, and should be scrapped.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention prepares trailing edge detection templates and chord length detection templates based on the theoretical model contour of the blade, and judges whether the blade exhaust edge patching and grinding is in place by the fit between the trailing edge detection templates and chord length detection templates and the blade and the distance between the two. The operation is simple and convenient, and the grinding amount can be repeatedly checked during the grinding process. It can be better integrated into the patching and grinding work, improves production efficiency, makes it easy to control the accuracy of the grinding amount, and reduces the scrap rate. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the existing nozzle ring structure;

[0025] Figure 2 This is a schematic diagram of the tail edge detection template structure in this invention;

[0026] Figure 3 This is a schematic diagram of the chord length detection template structure in this invention;

[0027] Figure 4 This is a schematic diagram of the inspection after the blade exhaust edge of the nozzle ring in this invention has been polished and patched;

[0028] Figure 5 In this invention Figure 4 Another perspective illustration;

[0029] Figure 6 In this invention Figure 4 A plan view;

[0030] Figure 7 In this invention Figure 6 Schematic diagram of the AA section.

[0031] In the diagram: 1. Blade; 11. Blade exhaust edge; 12. Blade intake edge; 13. Blade back side; 2. Nozzle ring outer ring; 3. Nozzle ring inner ring; 4. Trailing edge detection template; 5. Chord length detection template; 51. Bending structure; 6. Positioning structure. Detailed Implementation

[0032] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. 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.

[0033] Combination Figures 2 to 7 This embodiment describes a method for detecting the grinding and repair of nozzle ring blades, which includes the following steps:

[0034] S1. Inspection preparation: Prepare trailing edge inspection template 4 and chord length inspection template 5 according to the design dimensions of blade 1. Trailing edge inspection template 4 is fitted with the outline of the exhaust edge 11 of the blade, and chord length inspection template 5 is fitted with the outline from the back side 13 of the blade to the intake edge 12 of the blade. Specifically, trailing edge inspection template 4 and chord length inspection template 5 are prepared by photosensitive resin 3D printing or metal processing. In metal processing, investment casting can be used.

[0035] S2. Exhaust edge grinding test: After grinding the exhaust edge 11 of the blade to a certain extent, insert the trailing edge test plate 4 into the exhaust edge 11 of the blade and observe whether the trailing edge test plate 4 is fully inserted into the exhaust edge 11 of the blade. If it is not fully inserted, grind it again according to the gap between the inner wall of the trailing edge test plate 4 and the exhaust edge 11 of the blade, until the trailing edge test plate 4 is fully inserted into the exhaust edge 11 of the blade and the inner wall of the trailing edge test plate 4 is in contact with the exhaust edge 11 of the blade without shaking. If the trailing edge test plate 4 is not in contact with the exhaust edge 11 of the blade after being fully inserted into the exhaust edge 11 of the blade and the trailing edge test plate 4 can shake, it means that the grinding is excessive and difficult to repair, and it should be scrapped.

[0036] S3. Blade 1 chord length inspection: After the blade exhaust edge 11 is polished, the chord length inspection sample 5 is attached to the blade back side 13. The normal distance between the chord length inspection sample and the end face of the trailing edge inspection sample 4 on the blade back side 13 is measured. When the normal distance is 20mm, the patch polishing is qualified. If the normal distance is greater than 20mm, the blade 1 chord length is too large and the blade exhaust edge 11 needs to be polished again. The tolerance of the normal distance is ±0.01mm. If the normal distance is less than 20mm, it means that the trailing edge of the blade exhaust edge 11 has been polished too much and is difficult to repair, so it should be scrapped.

[0037] Furthermore, both the trailing edge detection template 4 and the chord length detection template 5 are provided with a positioning structure 6 that fits against the outer ring 2 of the nozzle ring on one side. The positioning structure 6 is formed by folding the sides of the two detection templates upwards. The height of the positioning structure 6 is 2-3 mm. The positioning structure 6 can position the trailing edge detection template 4 and the chord length detection template 5 in a lateral position. The cross-section of the trailing edge detection template 4 is a U-shaped structure, which can wrap around the trailing edge 11 of the blade exhaust edge, and the end face of the trailing edge detection template 4 is 3-5 mm away from the trailing edge of the blade exhaust edge 11. One end of the chord length detection template 5 is provided with a bending structure 51. The bending structure 51 fits against the blade intake edge 12 and extends to the front side of the blade 1. During detection, the bending structure 51 of the chord length detection template 5 hooks onto the blade intake edge 12 for positioning. The distance between the trailing edge inspection template 4 and the chord length inspection template 5 and the inner ring 3 of the nozzle ring is 4-6 mm, which facilitates the insertion and measurement of the fit between the trailing edge inspection template 4 and the chord length inspection template 5 and the profile of the blade 1. To ensure inspection accuracy, the profile tolerance of the contact surface between the trailing edge inspection template 4 and the chord length inspection template 5 and the blade 1 is -0.01 mm to -0.04 mm.

[0038] It is worth noting that, in order to avoid excessive polishing, the amount of polishing should not be too much each time the subsidy is polished. The polishing operation should be carried out on the basis of each inspection. In this example, the subsidy is set at the trailing edge of the blade exhaust edge 11, and the trailing edge inspection sample 4 is also used to inspect the trailing edge of the blade exhaust edge 11.

[0039] The working principle of this invention is as follows: a trailing edge detection template 4 and a chord length detection template 5 are prepared based on the theoretical model contour of blade 1. The wear and tear of the exhaust edge 11 of the blade is judged by the fit between the trailing edge detection template 4 and the chord length detection template 5 and blade 1, as well as the distance between them. The operation is simple and convenient. The amount of grinding can be repeatedly checked during the grinding process. It can be better integrated into the grinding work, improve production efficiency, make it easy to control the accuracy of the grinding amount, and reduce the scrap rate.

[0040] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0041] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for detecting the grinding and repair of nozzle ring blades, characterized in that, Includes the following steps: S1. Inspection Preparation: Prepare trailing edge inspection templates and chord length inspection templates according to the blade design dimensions. The trailing edge inspection template fits the exhaust edge contour of the blade, and the chord length inspection template fits from the back side of the blade to the intake edge contour. Both the trailing edge inspection template and the chord length inspection template are prepared by photosensitive resin 3D printing or metal processing. The side of the trailing edge inspection template and the chord length inspection template near the outer ring of the nozzle ring is provided with a positioning structure that fits the outer ring of the nozzle ring. The cross-section of the trailing edge inspection template is a U-shaped structure, which can wrap the trailing edge of the exhaust edge of the blade. The end face of the trailing edge inspection template is 3~5mm away from the trailing edge of the exhaust edge of the blade. The distance between the trailing edge inspection template and the chord length inspection template and the inner ring of the nozzle ring is 4-6mm. The contour tolerance of the trailing edge inspection template and the chord length inspection template and the blade fitting surface is -0.01mm~-0.04mm. S2. Exhaust edge grinding inspection: After grinding the exhaust edge of the blade to a certain extent, insert the trailing edge inspection template into the exhaust edge of the blade and observe whether the trailing edge inspection template is fully inserted into the exhaust edge of the blade. If it is not fully inserted, grind it again to a certain extent according to the gap between the inner wall of the trailing edge inspection template and the exhaust edge of the blade until the trailing edge inspection template is fully inserted into the exhaust edge of the blade and the inner wall of the trailing edge inspection template is in close contact with the exhaust edge of the blade without shaking. S3. Blade chord length detection: After the blade exhaust edge is polished, the chord length detection template is attached to the back side of the blade, and the normal distance between the chord length detection template on the back side of the blade and the end face of the trailing edge detection template is measured. When the normal distance is 20mm, the patch polishing is qualified. If the normal distance is greater than 20mm, the blade chord length is too large, and the blade exhaust edge patch needs to be polished again.

2. The method for testing the patching and grinding of nozzle ring blades according to claim 1, characterized in that, In step S1, one end of the chord length detection template is provided with a bending structure, which is attached to the air intake edge of the blade and extends to the front side of the blade.

3. The method for testing the patching and grinding of nozzle ring blades according to claim 1, characterized in that, If, in step S2, the trailing edge detection template is not in contact with the blade exhaust edge after being fully inserted and the trailing edge detection template can wobble, it indicates that excessive grinding has been applied, making it difficult to repair and requiring scrapping.

4. The method for testing the patching and grinding of nozzle ring blades according to claim 1, characterized in that, The tolerance for the normal distance in step S3 is ±0.01mm.

5. A method for testing the grinding and patching of nozzle ring blades according to claim 1 or 4, characterized in that, If the normal distance in step S3 is less than 20mm, it indicates that the trailing edge of the exhaust edge of the blade has been excessively ground and is difficult to repair, so it should be scrapped.

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