Annular groove processing method, annular groove and aircraft engine

Abstract

The present invention discloses an annular slot processing method, an annular slot and an aircraft engine, comprising the following steps: S1, enlarging the opening of the slot; S2, processing the inner surface of the enlarged slot; S3, repairing the enlarged slot to make it finally formed. The slot includes a first side and a second side, the first side is a short side, and the second side is a long side. The use of the above processing method has the following advantages: first, by enlarging the size of the slot, the processability of the turning process can be improved, and the use of different tools for processing before the two is avoided, and the tool connection is further avoided, which fundamentally eliminates the problem of tool connection, reduces subsequent polishing and repair, improves efficiency, and finally repairs it to form the final design requirements of the part.

Description

Technical Field

[0001] The invention belongs to the field of mechanical manufacturing, and in particular relates to an annular slot processing method, an annular slot and an aeroengine. Background Art

[0002] like Figure 1 As shown in the figure, a certain type of component structure in an aircraft engine, such as a combustion chamber flame tube, has an annular slot designed on the inner ring and outer ring inlet end wall of the flame tube, and a circle of air film holes are processed in the narrow slot. The gas enters from the air film holes and then passes through the slot, which is conducive to the formation of the first and end air films and enhances the cooling effect. For this type of annular slot structure, the slot width is significantly smaller than the depth, and the ratio of the slot width to the depth is about 1:3, which is a deep narrow slot. The turning method is commonly used for the processing of this structure.

[0003] like Figure 2-3 As shown, since the slot is narrow and the material of such parts is generally a high-temperature alloy material that is difficult to cut, the prior art usually uses a grooving tool to process the entire slot. The grooving tool used is relatively slender, which limits the tool feed size, resulting in extremely low cutting efficiency and high tool wear. Therefore, the tool needs to be replaced frequently, thereby increasing the tool cost. In addition, due to the poor rigidity of the tool, the temperature of the processing part is high, and the tool is prone to chipping.

[0004] Finally, since the slit is processed with a grooving tool, and one side of the slit is a profile, and the profile is processed with an inner or outer cylindrical tool, a large cutter connection is easily generated between the slit and the profile, and the size of the cutter connection can reach more than 0.1 mm, which will affect the product quality. Additional polishing, grinding and other processes are required to remove it and make it a smooth transition, which increases processing time and cost and is not conducive to batch production. Summary of the invention

[0005] The technical problem to be solved by the present invention is to overcome the defects of low processing efficiency, short tool life and easy tool connection in the prior art, and to provide a ring-shaped slot processing method and a ring-shaped slot.

[0006] The present invention solves the above technical problems through the following technical solutions:

[0007] A method for processing an annular groove comprises the following steps:

[0008] S1, expand the opening of the slot;

[0009] S2, processing the inner surface of the enlarged slot;

[0010] S3, repairing the enlarged seam to give it a final shape.

[0011] The slot includes a first side and a second side, the first side is a short side, and the second side is a long side.

[0012] In this technical solution, firstly, by enlarging the size of the slot, the processability of the turning process can be improved, and the use of different tools for processing the two can be avoided, further avoiding the problem of tool connection, fundamentally eliminating the problem of tool connection, reducing subsequent polishing and repair, improving efficiency, and finally repairing it to form the final design requirements of the part.

[0013] Preferably, in S1, expanding the opening of the slot includes: expanding the first side of the slot away from the second side by spreading.

[0014] In the present technical solution, the dimension development method is adopted, that is, the short side of the slit is rotated at a certain point (such as the intersection point of the root and the fillet) according to the final size, and finally an angle is formed with the long side, thereby expanding the root opening size, forming a structure with better openness, improving the turning processability, and facilitating the entry of the tool.

[0015] Preferably, the angle formed by the first side and the second side of the slot is in a range of 30° to 45°.

[0016] In this technical solution, in order to achieve the effect of convenient processing of the slit, the larger the angle, the better. In order to ensure the rigidity of the tool, the front cutting edge of the tool must be an acute angle. However, the smaller the angle, the worse the rigidity. Therefore, the minimum angle is not less than 30°. At the same time, in order to facilitate the subsequent reading of the slit, the angle should not be too large to facilitate plastic deformation. Therefore, the maximum angle is not greater than 45°.

[0017] Preferably, in S2, processing the enlarged inner surface of the slot includes: using a turning tool to process the inner surface of the slot and processing along the slot profile to the root of the slot at one time.

[0018] In this technical solution, since the slot profile is processed by an inner or outer round tool in the prior art, the intersection between the two tools is bound to produce a cutter connection, the size of which can reach more than 0.1mm, and a subsequent polishing process is required to remove the cutter connection, which increases the processing time and cost and is not conducive to batch production. The turning tool used in this technical solution can process the slot profile and the root at one time, without having to process the slot multiple times, which reduces the processing efficiency.

[0019] Preferably, the machining allowance of the slot profile is not less than 0.05 mm.

[0020] In the present technical solution, a machining allowance of not less than 0.05 mm is left for the groove profile for processing by the turning tool so that the long side of the groove can be formed at one time without any tool connection. If there is no machining allowance, the turning tool will form a tool connection step on the long side of the groove at the root of the groove, which is inconvenient to remove.

[0021] Preferably, the size of the turning tool matches the root size of the slot.

[0022] In this technical solution, since the shape of the turning tool used is consistent with the size of the root of the slot, the use of different tools for processing the two is avoided, and the connection of tools is further avoided, which fundamentally eliminates the problem of tool connection, reduces subsequent polishing and repair, and improves efficiency.

[0023] Preferably, the turning tool comprises a rounded corner portion, and the rounded corner portion is a cutting edge.

[0024] In this technical solution, compared with the groove cutter in the prior art, the cutting edge can improve cutting efficiency, tool life and reduce processing and manufacturing costs.

[0025] Preferably, in S3, repairing the enlarged slit to give it a final shape comprises: repairing the enlarged slit by rolling to give it a final shape.

[0026] In the present technical solution, since the seam is a wake-up structure, it is very suitable for turning processing. In addition, the workpiece is rotating, so it is convenient to repair it by rolling. After the surface of one side of the seam is rolled, the original shape of the seam can be restored, and the surface layer is strengthened to increase the ultimate strength and yield point. The performance, fatigue resistance, wear resistance and corrosion resistance of the workpiece are significantly improved.

[0027] The present invention also provides an annular slot, which is processed according to the above method.

[0028] The present invention further provides an aircraft engine, the aircraft engine comprising a combustion chamber flame tube, the combustion chamber flame tube comprising the annular slot described above.

[0029] The present invention also provides an annular slot, which is processed according to the above method.

[0030] The positive and progressive effects of the present invention are: first, by expanding the size of the slot, the corresponding depth of the slot becomes shallower, forming a structure with better openness, which can improve the processability of turning. Then, by using the designed forming tool, the slot profile and the root can be processed and formed at one time, without having to process the slot multiple times, which reduces the processing efficiency. In addition, since the slot profile is processed by an inner or outer circle tool in the prior art, the intersection between the two tools is bound to produce a cutter connection, and the size of the cutter connection can reach more than 0.1mm. It is necessary to use a subsequent polishing process to remove the cutter connection, which increases the processing time and cost and is not conducive to batch production. Since the shape of the forming tool matches the size of the root of the slot, it avoids the use of different tools for processing the two before, further avoids the cutter connection, fundamentally eliminates the problem of cutter connection, reduces subsequent polishing and repairs, and improves efficiency. Finally, the expanded slot side is rolled and formed by rolling to form the final design requirements of the part. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the inner and outer ring structure of a flame tube in an engine combustion chamber;

[0032] Figure 2 A schematic diagram of a method for machining an inner slit by a grooving cutter commonly used in the prior art;

[0033] Figure 3 It is a schematic diagram of a method of machining an outer slit by a grooving cutter commonly used in the prior art;

[0034] Figure 4 This is a flow chart of the annular slot processing in the present invention;

[0035] Figure 5 A schematic diagram of the first side of the slot formed in the present invention;

[0036] Figure 6 It is a schematic diagram of one-step forming processing using a forming knife that is consistent with the root of the slit in the present invention;

[0037] Figure 7 It is a schematic diagram of the final forming by roller rolling method in the invention.

[0038] Description of reference numerals:

[0039] Slot 1

[0040] First side 2

[0041] Second side 3

[0042] Root 4

[0043] Forming knife 5

[0044] Roller structure 6 DETAILED DESCRIPTION

[0045] The present invention is further described below by way of examples, but the present invention is not limited to the scope of the examples.

[0046] Example 1

[0047] This embodiment is aimed at a certain type of component structure in an aircraft engine, such as the annular grooves on the inner and outer ring inlet end walls of the combustion chamber flame tube, and a circle of air film holes is processed in the narrow groove. The gas enters from the air film holes and then passes through the groove, which is conducive to the formation of the first and end air films and enhances the cooling effect. The width of the groove is significantly smaller than the depth, and the ratio of the groove width to the depth is about 1:3, which is a deep narrow groove. For this type of annular groove, this embodiment provides an annular groove processing method, such as Figure 4 As shown, the following steps are included:

[0048] S1, expanding the opening of slot 1;

[0049] S2, processing the inner surface of the enlarged slot 1;

[0050] S3, repairing the enlarged slot 1 to give it a final shape.

[0051] The slot includes a first side 2 and a second side 3 , wherein the first side 2 is a short side of the slot, and the second side 3 is a long side of the slot.

[0052] like Figure 5 As shown, specifically, in S1, expanding the opening of the slot 1 includes: expanding the first side 2 of the slot 1 away from the second side 3 by expanding. The dotted line portion is the state when the first side 2 is not expanded.

[0053] Through the size development method, that is, by rotating the short side of the slot at a certain point (such as the tangent point of the root and the fillet) according to the final size, it finally forms an angle with the long side, thereby expanding the root opening size, forming a structure with better openness, improving the turning processability, and facilitating the entry of the tool.

[0054] It should be noted that the solution for expanding the slot opening is not limited to the above-mentioned development method, as long as the slot opening can be expanded to enable the forming knife to perform subsequent processing.

[0055] In the present embodiment, the angle formed by the first side 2 and the second side 3 of the slit through the unfolding method is 45°. It should be noted that the angle between the first side and the second side after the unfolding method is not limited to the above 45°. In other embodiments, the angle may also be 30°, etc. However, if the angle formed by the first side and the second side is too small, there will not be enough space for the forming knife to process along the profile of the slit to the root of the slit at one time. If the angle formed by the first side and the second side is too small, it may cause the root of the slit to deform, and it cannot be restored in the subsequent rolling process, affecting the quality. Therefore, in the present embodiment, 45° is a more compromising angle, which has enough space for the forming knife to process along the profile of the slit to the root of the slit at one time, and will not affect the deformation of the root of the slit, resulting in quality problems. In order to facilitate the processing of the slit, the larger the angle, the better. In order to ensure the rigidity of the tool, the front cutting edge of the tool must be an acute angle. However, the smaller the angle, the worse the rigidity. Therefore, the minimum angle is not less than 30°. At the same time, in order to facilitate the subsequent reading of the slit, the angle should not be too large to facilitate plastic deformation. Therefore, the maximum angle is not greater than 45°.

[0056] like Figure 6 As shown, specifically, in S2, processing the inner surface of the enlarged slot 1 includes: using a turning tool to process the inner surface of the slot and processing along the profile of the slot 1 to the root 4 of the slot 1 at one time.

[0057] Since the slot profile is processed by inner or outer round tools in the prior art, the intersection between the two tools is bound to produce a cutter connection, the size of which can reach more than 0.1mm, and a subsequent polishing process is required to remove the cutter connection, which increases the processing time and cost and is not conducive to batch production. The turning tool used in this technical solution can process the slot profile and the root into shape at one time, without having to process the slot multiple times, which reduces the processing efficiency.

[0058] In this embodiment, the turning tool is a pre-designed forming tool 5, the size of which matches the root size of the slot. Since the shape of the forming tool used matches the root size of the slot, it is avoided that the two are processed by different tools before, and the connection of tools is further avoided, which fundamentally eliminates the problem of tool connection, reduces subsequent polishing and repair, and improves efficiency. The rounded corner part of the forming tool is the cutting edge. Compared with the slotting tool in the prior art, the cutting edge can improve cutting efficiency, tool life and reduce processing and manufacturing costs.

[0059] The forming knife 5 is generally made of cemented carbide, and its hardness needs to be harder than the workpiece material (i.e., the slot). The forming knife used in this embodiment is a high-temperature alloy tool, and the slot is made of a high-temperature alloy material (GH5188). The slot material in this embodiment is generally required to have good ductility and low yield strength to facilitate subsequent processing of the slot to make it plastically formed.

[0060] In this embodiment, the machining allowance of the profile of the slot 1 is not less than 0.05 mm. This allowance is used for machining the turning tool so that the long side of the slot can be formed at one time without a tool joint. If there is no machining allowance, the turning tool will form a tool joint step on the long side of the slot at the root of the slot, which is inconvenient to remove.

[0061] like Figure 7 As shown, specifically, in S3, repairing the enlarged slit 1 to make it finally formed includes: repairing the enlarged slit by rolling to make it finally formed. In this embodiment, the rolling method is specifically to use a roller structure 6 to roll the enlarged slit 1. Each time the rolling is performed, the angle between the first side and the second side of the slit gradually decreases until the angle is 0, that is, the two sides tend to be parallel.

[0062] Taking into account that there will be a certain amount of springback, a slight compensation will be made during rolling, such as rolling the second side with a little more feed. At the same time, in order to prevent the slot from deforming due to overpressure, an annular block can be placed in the slot to serve as a limiter.

[0063] Through the above rolling method, the original shape of the slot can be restored, and the surface layer is strengthened to increase the ultimate strength and yield point, and the performance, fatigue resistance, wear resistance and corrosion resistance of the workpiece are significantly improved.

[0064] It should be noted that since the slit is annular in structure, it is very suitable for turning processing, and the workpiece is rotating, so it is convenient to use rolling. However, the method for repairing it after processing is not limited to the rolling method provided in this embodiment, and mold pressing can also be used. However, compared with using rolling, using mold pressing to repair the slit is costly and inefficient.

[0065] Before rolling, the part of the slot 1 to be rolled needs to be pre-treated, and the pre-treatment method is: 1. Heating to make the part to be rolled easier to plastically deform. 2. Adding lubricating oil to facilitate extrusion without causing "tearing" on the slot surface.

[0066] In the present technical solution, since the slot 1 is an annular structure, it is very suitable for turning processing. In addition, the workpiece is rotating, which makes it easy to repair it by rolling. After the surface of one side of the slot is rolled, the original shape of the slot can be restored, and the surface layer is strengthened to increase the ultimate strength and yield point. The performance, fatigue resistance, wear resistance and corrosion resistance of the workpiece are significantly improved.

[0067] In this embodiment, the turning process and the rolling process are both performed on a lathe. This method can realize the processing of annular slots on an outer circle or an inner circle, and can avoid the problems caused by secondary clamping.

[0068] It should be noted that the above-mentioned processing method for the annular groove is not only suitable for processing parts with deep narrow grooves such as military and civil aviation engines, but also can be used for parts with similar structures in other industries.

[0069] This embodiment also provides an annular slot, which is processed according to the above method.

[0070] According to the above steps, first, by expanding the size of the slot, the corresponding depth of the slot becomes shallower, forming a structure with better openness, which can improve the processability of turning. Then, the designed forming tool is used to process the slot profile and the root at one time, without having to process the slot multiple times, which reduces the processing efficiency. In addition, since the slot profile is processed by an inner or outer circle tool in the prior art, the intersection between the two tools is bound to produce a cutter connection, and the size of the cutter connection can reach more than 0.1mm. It is necessary to use a subsequent polishing process to remove the cutter connection, which increases the processing time and cost and is not conducive to batch production. Since the shape of the forming tool matches the size of the root of the slot, it avoids the use of different tools for processing the two before, further avoids the cutter connection, fundamentally eliminates the problem of cutter connection, reduces subsequent polishing and repairs, and improves efficiency. Finally, the rolling method is used to roll one side of the expanded slot to form the final design requirements of the part.

[0071] This embodiment also provides an aircraft engine, which includes a combustion chamber flame tube, and the combustion chamber flame tube includes the annular slot described above.

[0072] Although the specific embodiments of the present invention are described above, it should be understood by those skilled in the art that this is only for illustration and the protection scope of the present invention is defined by the appended claims. Those skilled in the art may make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but these changes and modifications all fall within the protection scope of the present invention.

Claims

1. A method for processing an annular slot, characterized in that: The following steps are involved: S1, expand the opening of the slot; S2, processing the inner surface of the enlarged slot; S3, repairing the enlarged seam to make it finally formed; Wherein, the slot comprises a first side and a second side, the first side is a short side, and the second side is a long side; Wherein, in S2, processing the enlarged inner surface of the slot includes: A turning tool is used to machine the inner surface of the slot and to machine along the slot profile to the root of the slot at one time.

2. The method for processing an annular groove according to claim 1, characterized in that: In S1, the opening of the enlarged slot includes: The first side of the slot is expanded away from the second side by generating.

3. The method for processing an annular groove according to claim 2, characterized in that: An angle formed by the first side and the second side of the slot is in a range of 30° to 45°.

4. The method for processing an annular groove according to claim 1, characterized in that: The machining allowance of the slot profile is not less than 0.05 mm.

5. The method for processing an annular groove according to claim 1, characterized in that: The size of the turning tool matches the root size of the slot.

6. The method for processing an annular groove according to claim 1, characterized in that: The turning tool includes a rounded corner portion, which is a cutting edge.

7. The method for processing an annular groove according to claim 1, characterized in that: In S3, repairing the enlarged slot to make it finally formed includes: The enlarged seam is repaired by rolling to give it a final shape.

8. An annular slot, characterized in that: The slot is processed according to the method according to any one of claims 1-7.

9. An aircraft engine, characterized in that: The aircraft engine comprises a combustion chamber flame tube, and the combustion chamber flame tube comprises the annular slot as described in claim 8.

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