Blade tenon tooth repairing method

Abstract

The invention belongs to the field of turbine blade repairing, and discloses a blade tenon tooth repairing method which comprises the following steps: grinding a grinding part matched with a tenon tooth of a blade to be repaired on an oilstone; wherein the grinding part is consistent with the surface shape of a tenon tooth of a blade to be repaired, and the size is reduced according to a preset proportion; the grinding part of the oilstone is completely soaked in lubricating oil for preset time; and the surface of the grinding part of the soaked oilstone is tightly attached to the tenon tooth surface of the to-be-repaired blade to be ground and repaired, the error between the actual size and the target size between the opposite tenon tooth rolling rods is measured at intervals in the repairing process, and tenon tooth repairing of the to-be-repaired blade is completed when the error is smaller than a preset error threshold value. By analyzing the shape of the cutter, the operation mode, the quality of the surface to be repaired and the like in the repairing process, the problem that the original blade cannot meet the design and assembly test run requirements after being repaired is solved, effective repairing of the blade with the tenon tooth defect is achieved, and therefore the manufacturing cost is effectively reduced, and resource waste is reduced.

Description

Technical Field

[0001] The invention belongs to the field of turbine blade repair and relates to a blade tenon repair method. Background Art

[0002] As a key part of the engine, blades play a vital role in aircraft or gas turbines. The relevant matching dimensions of the blades are not only an important assembly indicator before the first test run, but also an important inspection requirement during the engine overhaul. As a key part of the blade, the tenon has always been a focus of attention during blade processing, assembly, test runs and engine return to the factory. The main surface quality problems of the tenon include cracks, wrinkles and dimensional tolerances, and cracks and wrinkles account for a large proportion of the fluorescent inspection when the engine is returned to the factory. The above problems will make it impossible to assemble the blades and the turbine disk, affecting the safety of the engine.

[0003] At present, because there is no precise repair method, the blades are usually replaced when such situations occur. However, blades are usually made of special alloy materials, which are not only expensive but also difficult to process, so the manufacturing cost of a single blade is considerable. In addition, replacing blades requires professional technicians to perform precise operations, including disassembling old blades, cleaning the mounting surface, installing new blades, and debugging, all of which require a lot of manpower and time. Summary of the invention

[0004] The purpose of the present invention is to overcome the above-mentioned shortcomings of the prior art and provide a blade tenon repair method.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] The present invention provides a method for repairing tenon teeth of a blade, comprising: grinding a grinding portion on an oilstone to match the tenon teeth of a blade to be repaired; wherein the grinding portion has a surface shape consistent with the tenon teeth of the blade to be repaired, and a size reduced according to a preset ratio; soaking the grinding portion of the oilstone in lubricating oil for a preset time; grinding and repairing the surface of the soaked grinding portion of the oilstone against the tenon teeth surface of the blade to be repaired, and measuring the error between the actual size and the target size relative to the tenon teeth roller at intervals during the repair process, and completing the tenon teeth repair of the blade to be repaired when the error is less than a preset error threshold.

[0007] Optionally, when grinding a grinding portion on the oilstone to match the tenon of the blade to be repaired, the length of the grinding portion does not exceed 2 / 3 of the length of the oilstone, the width of the grinding portion does not exceed 1 / 2 of the width of the oilstone, and the height of the grinding portion does not exceed 1 / 6 of the height of the oilstone.

[0008] Optionally, the oilstone is a triangular prism oilstone, and the bottom surface angle of one side of the oilstone where the grinding portion is provided is smaller than the tenon angle of the blade to be repaired.

[0009] Optionally, when the thermal conductivity and thermal diffusivity of the material of the blade to be repaired are both higher than the corresponding preset thresholds, before the grinding repair of the grinding portion of the soaked oilstone is carried out close to the tenon surface of the blade to be repaired, it also includes: using a rubber wheel to enter along the tenon side surface of the repaired blade and repairing it on a polishing machine along the entire tenon surface, and during the repair process, the blade basin and blade back of the tenon are repaired symmetrically.

[0010] Optionally, when the rubber wheel is used to enter along one side surface of the tenon of the repair blade and repair along the entire tenon surface on the polishing machine, the linear speed of the rubber wheel is 18 to 22 m / s.

[0011] Optionally, when the rubber wheel is used to enter along one side surface of the tenon of the repair blade and repair along the entire tenon surface on the polishing machine, the diameter of the rubber wheel is 60 to 125 mm.

[0012] Optionally, when the rubber wheel is used to enter along one side surface of the tenon of the repair blade and repair along the entire tenon surface on a polishing machine, the rotation speed of the polishing machine is 3000-7000 rpm.

[0013] Optionally, before grinding the grinding portion on the oilstone to match the tenon of the blade to be repaired, the method also includes: obtaining the defect type of the tenon of the blade to be repaired; when the defect type of the tenon of the blade to be repaired is wrinkles on the non-working surface and width dimension deviation, continuing with subsequent repair steps; when the defect type of the tenon of the blade to be repaired is wrinkles on the working surface and surface cracks, ending the repair.

[0014] Optionally, when the material of the blade to be repaired is a cast high-temperature alloy mainly containing Co, the lubricating oil does not contain copper and lead; when the material of the blade to be repaired is a cast high-temperature alloy mainly containing Cr, the lubricating oil does not contain copper, lead, tin and bismuth.

[0015] Optionally, after completing the tenon repair of the blade to be repaired, the method further includes: performing visual and fluorescent inspections on the tenon surface of the blade to be repaired.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] The blade tenon repair method of the present invention adopts an oil stone as a repair tool, which is adapted to the unique structural characteristics, material characteristics and defect characteristics of the blade tenon, realizes a repair process with strong stability, and the repair surface has no scratches, and basically no further trimming is required. At the same time, by grinding a grinding part matching the blade tenon to be repaired on the oil stone, the accuracy and pertinence of the repair tool are ensured, which not only improves the accuracy of the repair, but also effectively avoids the problem of poor repair effect caused by repair damage. In addition, by reducing the size, it can be ensured that the oil stone will not damage the surface that does not need to be ground during grinding, and the part that needs to be repaired can be gradually and evenly removed, thereby achieving an ideal repair effect. The grinding part of the oil stone is immersed in lubricating oil for a preset time, which can effectively reduce friction and heat during the grinding process, and is more conducive to removing surface defects of parts. In addition, during the repair process, the error between the actual size and the target size relative to the tenon roller is measured at intervals, which can not only timely adjust the grinding force and angle to ensure that the size of the tenon after the repair is accurate and correct, but also timely understand the current repair effect to avoid excessive repair causing the blade to be scrapped. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The present invention is a flowchart of a blade tenon repair method according to an embodiment of the present invention.

[0019] Figure 2 Schematic diagram of a blade tenon structure according to an embodiment of the present invention.

[0020] Figure 3 This is a schematic diagram of repairing a rubber wheel according to an embodiment of the present invention.

[0021] Figure 4 Schematic diagram of the oilstone structure according to an embodiment of the present invention.

[0022] Figure 5 Schematic diagram of oilstone repair according to an embodiment of the present invention.

[0023] Figure 6 Schematic diagram of another blade tenon structure according to an embodiment of the present invention.

[0024] Among them: 1- non-working surface of tenon; 2- rubber wheel; 3- oilstone; 4- lifting position; 5- pressing position. DETAILED DESCRIPTION

[0025] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0026] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0027] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0028] See also Figure 1 In one embodiment of the present invention, a blade tenon repair method is provided to achieve effective repair of blades with defective tenons, reduce manufacturing costs and reduce resource waste.

[0029] Specifically, the blade tenon repair method of the present invention comprises the following steps:

[0030] S1: Grinding a grinding portion on an oilstone to match the tenon of the blade to be repaired; wherein the grinding portion has the same surface shape as the tenon of the blade to be repaired, and the size is reduced according to a preset ratio.

[0031] S2: Soak the entire grinding part of the oilstone in lubricating oil for a preset time.

[0032] S3: The grinding surface of the soaked oilstone is placed close to the tenon surface of the blade to be repaired for grinding and repair, and the error between the actual size and the target size between the tenon rollers is measured at intervals during the repair process. When the error is less than a preset error threshold, the tenon repair of the blade to be repaired is completed.

[0033] Specifically, by analyzing the tool shape, operation method and quality of the surface to be repaired during the repair process, the problem of the original blade being unable to meet the design and assembly test requirements after repair was overcome.

[0034] In the selection of repair tools, we tried to analyze and test tools of different materials such as files and small grinding wheels. Since the part to be repaired is the tenon part of the blade, the main characteristics of the repair are superficial wrinkles with a depth of no more than 0.02mm or out-of-size parts. Using a small grinding wheel will increase the stress concentration of the repaired part, causing more obvious cracks; using a file for repair will result in obvious scratches on the repaired part and its surroundings; the above two repair methods will result in no guarantee of safety performance.

[0035] The present invention uses an oil stone as a repair tool. This gentle method has strong stability during the repair process, and the final repaired surface has no scratches. Basically, no further finishing is required. Considering quality and economy, this type of repair method is more suitable for engineering applications.

[0036] The blade tenon repair method of the present invention adopts an oil stone as a repair tool, which is adapted to the unique structural characteristics, material characteristics and defect characteristics of the blade tenon, realizes a repair process with strong stability, and the repair surface has no scratches, and basically no further trimming is required. At the same time, by grinding a grinding part matching the blade tenon to be repaired on the oil stone, the accuracy and pertinence of the repair tool are ensured, which not only improves the accuracy of the repair, but also effectively avoids the problem of poor repair effect caused by repair damage. In addition, by reducing the size, it can be ensured that the oil stone will not damage the surface that does not need to be ground during grinding, and the part that needs to be repaired can be gradually and evenly removed, thereby achieving an ideal repair effect. The grinding part of the oil stone is immersed in lubricating oil for a preset time, which can effectively reduce friction and heat during the grinding process, and is more conducive to removing surface defects of parts. In addition, during the repair process, the error between the actual size and the target size relative to the tenon roller is measured at intervals, which can not only timely adjust the grinding force and angle to ensure that the size of the tenon after the repair is accurate and correct, but also timely understand the current repair effect to avoid excessive repair causing the blade to be scrapped.

[0037] In a possible implementation, when grinding a grinding portion on the oilstone to match the tenon of the blade to be repaired, the length of the grinding portion does not exceed 2 / 3 of the length of the oilstone, the width of the grinding portion does not exceed 1 / 2 of the width of the oilstone, and the height of the grinding portion does not exceed 1 / 6 of the height of the oilstone.

[0038] Specifically, limiting the specific size of the grinding part can ensure the efficiency and accuracy of the grinding operation. The width of the grinding part not exceeding 1 / 2 of the width of the oilstone is conducive to more precise grinding control, especially when processing complex or fine tenons, it can reduce errors and improve grinding accuracy. The height of the grinding part is limited to within 1 / 6 of the height of the oilstone, which helps maintain stability during the grinding process, reduce vibration or instability caused by excessively high grinding part, and further improve grinding quality and safety.

[0039] In a possible implementation manner, the oilstone is a triangular prism oilstone, and the bottom surface angle of one side of the oilstone where the grinding portion is provided is smaller than the tenon angle of the blade to be repaired.

[0040] Specifically, the bottom surface angle of one side of the grinding portion of the limit oilstone is set smaller than the tenon angle of the blade to be repaired, which can effectively avoid damage to the surface that does not need to be ground during grinding.

[0041] In a possible embodiment, before grinding a grinding portion on the oilstone to match the tenon of the blade to be repaired, the process also includes: obtaining the defect type of the tenon of the blade to be repaired; when the defect type of the tenon of the blade to be repaired is wrinkles on the non-working surface and width dimension out of tolerance, continuing with subsequent repair steps; when the defect type of the tenon of the blade to be repaired is wrinkles on the working surface and surface cracks, ending the repair.

[0042] Specifically, the three surface quality conditions of the tenon are classified into surface cracks, surface wrinkles and width dimension deviation. Among them, surface crack defects are not allowed to be repaired; surface wrinkles can only be repaired on the non-working surface of the tenon, and when the width dimension deviation is exceeded, the non-working surface can also be repaired.

[0043] In a possible embodiment, when the thermal conductivity and thermal diffusivity of the material of the blade to be repaired are both higher than the corresponding preset threshold values, before the grinding repair of the grinding portion of the soaked oilstone is carried out in close contact with the tenon surface of the blade to be repaired, it also includes: using a rubber wheel to enter along one side surface of the tenon of the repaired blade and repairing it on a polishing machine along the entire tenon surface, and during the repair process, the blade basin and blade back of the tenon are repaired symmetrically.

[0044] Specifically, for blades to be repaired whose thermal conductivity and thermal diffusivity are both higher than the preset threshold, a rubber wheel combined with a polishing machine is used for mechanical processing to perform pretreatment before oilstone grinding. On the one hand, it can significantly improve the repair speed and quickly remove damage or irregularities on the surface of the blade tenon in a mechanized manner, laying a good foundation for subsequent oilstone grinding. On the other hand, the flexibility of the rubber wheel ensures a close fit with the tenon surface, while reducing secondary damage that may be caused by direct hard contact and protecting the integrity of the blade. Furthermore, the symmetrical repair of the blade basin and blade back ensures the uniformity and balance of the tenon, which is crucial to the subsequent performance and life of the blade.

[0045] In a possible implementation manner, when the rubber wheel is used to enter along one side surface of the tenon of the repaired blade and repair along the entire tenon surface on the polishing machine, the line speed of the rubber wheel is 18-22 m / s.

[0046] Optionally, when the rubber wheel is used to enter along one side surface of the tenon of the repair blade and repair along the entire tenon surface on the polishing machine, the diameter of the rubber wheel is 60 to 125 mm.

[0047] Optionally, when the rubber wheel is used to enter along one side surface of the tenon of the repair blade and repair along the entire tenon surface on a polishing machine, the rotation speed of the polishing machine is 3000-7000 rpm.

[0048] In the process of pre-treating the tenons of the repaired blades with a rubber wheel and a polisher, the precise control of the parameters of setting the linear speed and diameter of the rubber wheel and the speed of the polisher brings multiple advantages. The appropriate linear speed ensures efficient contact and friction between the rubber wheel and the tenon surface, which can quickly remove damage without overheating or aggravating damage due to excessive speed. The wide range of rubber wheel diameters can flexibly cope with tenons of different sizes and shapes, achieving more comprehensive coverage and more uniform repair results. The precise control of the polisher speed makes the entire repair process smoother and more controllable.

[0049] In a possible implementation manner, after the tenon repair of the blade to be repaired is completed, the method further includes: visually and fluorescently inspecting the tenon surface of the blade to be repaired.

[0050] Specifically, tenon repair processing verification is carried out at the processing site, and visual and fluorescent inspections are used to determine whether the blades are crack-free and meet surface integrity requirements, thereby ensuring the quality of the repair.

[0051] In a possible implementation, the blade tenon repair method of the present invention is described by taking a working blade of a certain machine as an example. The Co content of this blade material is relatively high, and it belongs to a cast high-temperature alloy with poor machining performance. The size and repair position of the tenon to be repaired are as follows: Figure 2 shown.

[0052] The specific implementation steps are as follows:

[0053] 1. Before repair, measure the actual size between the relative tenon rollers and perform repairs within the dimensional tolerance.

[0054] 2. Use manual operation, see Figure 3 , use the rubber wheel (A80K) 2 to enter along one side of the tenon tooth, and trim along the entire tooth surface on the polishing machine JX-22. During repair, ensure that the tenon blade basin and blade back are repaired symmetrically.

[0055] 3. Grind the oilstone according to the size of the tenon to be repaired. Figure 4 The bottom angle α of the grinding part on one side of the oilstone is ground to 38 degrees (slightly smaller than the tenon angle), the length L of the grinding part is 7 mm, the width D of the grinding part is 5 mm, and the height H of the grinding part is 1 mm.

[0056] 4. Soak the area within 7mm of the oilstone in lubricating oil (without copper and lead).

[0057] 5. See Figure 5 During repair, place the grinding surface of the oilstone 3 close to the tenon surface, lift the bottom of the oilstone 3 at the lifting position 4, and press the oilstone 3 at the pressing position 5 to polish the entire tenon surface. During operation, the force on the entire surface must be uniform.

[0058] 6. When repairing, use a caliper to measure the actual size between the relative tenon rollers, and it is not allowed to exceed the target value.

[0059] 7. Clean the repaired surface of the blade after repair.

[0060] 8. Perform visual and fluorescent inspection of the repaired surface.

[0061] In this implementation, the tools used and the specific parameters are shown in Table 1:

[0062] Table 1

[0063] Serial number name Specifications / Parameters 1 Rubber wheel Diameter 60mm 2 Polishing Machine 7000 rpm 3 Whetstone WA300P ST 150×10×10

[0064] The tenon repair processing verification was carried out at the processing site. Visual and fluorescent inspections showed that there were no cracks and the surface integrity requirements were met. The assembly was completed in one go without replacing the blades and the test performance met all design indicators.

[0065] In a possible implementation, the blade tenon repair method of the present invention is described by taking a working blade of a certain machine as an example. The Cr content of this blade material is relatively high, and it belongs to a cast high-temperature alloy with good high-temperature performance, but its thermal conductivity and thermal diffusivity are very low, and its mechanical processing performance is poor and it is very easy to produce cracks and wrinkles. The tenon shape and repair part of the working blade that need to be repaired are as follows Figure 6 shown.

[0066] The specific technical implementation is as follows:

[0067] 1. Grind the oilstone according to the size of the tenon to be repaired, and grind the bottom angle α of the grinding part of the oilstone to 38 degrees (slightly smaller than the tenon angle). The length L of the grinding part is 10 mm, the width D of the grinding part is 7 mm, and the height H of the grinding part is 2 mm.

[0068] 2. Soak the area within 15 mm of the oilstone in lubricating oil (excluding copper, lead, tin and bismuth).

[0069] 3. When repairing, place one side of the oilstone close to the tenon surface, support the bottom of the oilstone while pressing the oilstone, and polish the entire tenon surface. The operation requires uniform force on the entire surface.

[0070] 4. When repairing, use a caliper to measure the actual size between the relative tenon rollers, and it is not allowed to exceed the target value.

[0071] 5. Clean the repaired surface of the blade after repair.

[0072] 6. Perform visual and fluorescent inspection of the repaired surface.

[0073] In this implementation, the tools used and the specific parameters are shown in Table 2:

[0074] Table 2

[0075] Serial number name Specifications / Parameters 1 Whetstone WA210P ST 150×10×10

[0076] The tenon repair processing verification was carried out at the processing site. Visual and fluorescent inspections showed that there were no cracks and the surface integrity requirements were met. The assembly was completed in one go without replacing the blades and the test performance met all design indicators.

[0077] The above contents are only for explaining the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A blade tenon repair method, characterized in that: include: Grinding a grinding portion on an oilstone to match the tenon of the blade to be repaired; wherein the grinding portion has the same surface shape as the tenon of the blade to be repaired, and the size is reduced according to a preset ratio; Soak the entire grinding part of the oilstone in lubricating oil for a preset time; The grinding surface of the soaked oilstone is placed close to the tenon surface of the blade to be repaired for grinding and repair, and the error between the actual size and the target size between the tenon rollers is measured at intervals during the repair process. When the error is less than the preset error threshold, the tenon repair of the blade to be repaired is completed.

2. The blade tenon repair method according to claim 1, characterized in that: When a grinding portion matching the tenon of the blade to be repaired is ground on the oilstone, the length of the grinding portion does not exceed 2 / 3 of the length of the oilstone, the width of the grinding portion does not exceed 1 / 2 of the width of the oilstone, and the height of the grinding portion does not exceed 1 / 6 of the height of the oilstone.

3. The blade tenon repair method according to claim 1, characterized in that: The oilstone is a triangular prism oilstone, and the bottom surface angle of one side of the oilstone where the grinding portion is arranged is smaller than the tenon angle of the blade to be repaired.

4. The blade tenon repair method according to claim 1, characterized in that: When the thermal conductivity and thermal diffusivity of the material of the blade to be repaired are both higher than the corresponding preset thresholds, before the grinding repair of the surface of the grinding portion of the soaked oilstone against the tenon surface of the blade to be repaired, the method further includes: A rubber wheel is used to enter along one side surface of the tenon of the repaired blade and repair is performed on a polishing machine along the entire tenon surface. During the repair process, the blade basin and blade back of the tenon are repaired symmetrically.

5. The blade tenon repair method according to claim 4, characterized in that: When the rubber wheel enters along one side surface of the tenon teeth of the repaired blade and repairs along the entire tenon tooth surface on the polishing machine, the line speed of the rubber wheel is 18-22 m / s.

6. The blade tenon repair method according to claim 4, characterized in that: When the rubber wheel is used to enter along one side surface of the tenon teeth of the repaired blade and repair along the entire tenon tooth surface on the polishing machine, the diameter of the rubber wheel is 60-125 mm.

7. The blade tenon repair method according to claim 4, characterized in that: When the rubber wheel is used to enter along one side surface of the tenon tooth of the repair blade and repair along the entire tenon tooth surface on the polishing machine, the rotation speed of the polishing machine is 3000-7000 revolutions / min.

8. The blade tenon repair method according to claim 1, characterized in that: Before the grinding portion matching the tenon teeth of the blade to be repaired is ground on the oilstone, the method further comprises: Obtain the defect type of the tenon of the blade to be repaired; when the defect type of the tenon of the blade to be repaired is wrinkles on the non-working surface and width dimension deviation, continue with subsequent repair steps; when the defect type of the tenon of the blade to be repaired is wrinkles on the working surface and surface cracks, end the repair.

9. The blade tenon repair method according to claim 1, characterized in that: When the material of the blade to be repaired is a cast high-temperature alloy mainly containing Co, the lubricating oil does not contain copper and lead; when the material of the blade to be repaired is a cast high-temperature alloy mainly containing Cr, the lubricating oil does not contain copper, lead, tin and bismuth.

10. The blade tenon repair method according to claim 1, characterized in that: After the tenon teeth of the blade to be repaired are repaired, the method further comprises: The tenon surfaces of the blades to be repaired are inspected visually and fluorescently.

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