Shot peening strengthening machining device and method for internal threads of aeronautical parts
By designing a shot peening device and method for strengthening the internal threads of aerospace parts, the problems of uneven shot peening and poor process adaptability were solved, achieving uniform strengthening and efficient production of internal threads, improving the fatigue strength and stress corrosion resistance of parts, and making it suitable for multi-variety small-batch production.
Patent Information
- Application Number
- CN202511469955.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-15
- Publication Date
- 2026-01-09
AI Technical Summary
Existing technologies lack dedicated shot peening devices for internal threads of aerospace parts, making it difficult for shot to cover evenly, affecting shot peening intensity and coverage. Furthermore, the lack of customized parameter systems results in poor process adaptability and an inability to meet the needs of multi-variety, small-batch production.
A shot peening strengthening device for internal threads of aerospace parts was designed, including a shot peening cover plate, shot peening gasket, shot peening plug, rod, shot peening cover, shot peening base and shot peening machine worktable. Through centerline coincidence design and parameter optimization, the uniformity of shot peening and processing efficiency are ensured. Nylon shot peening plug is used to protect the inside of the parts. Combined with specific parameters such as shot peening pressure, flow rate and rotation speed, uniform coverage is achieved.
It improves the fatigue strength and stress corrosion resistance of the internal threads of aerospace parts, provides good device protection, has short changeover and adjustment time, long service life, adapts to multi-variety small-batch production, and ensures timely delivery of aerospace products.
Smart Images
Figure CN121290280A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of surface strengthening technology for aerospace components, specifically to a shot peening strengthening device and method for the internal thread structure of aerospace components, used to improve the fatigue strength and stress corrosion resistance of the internal threads of aerospace components. Background Technology
[0002] Aerospace components are prone to fatigue cracking during pressure testing, with most cracks originating at the root of internal threads. Shot peening, which uses shot impact to induce plastic deformation on the internal thread surface, forms a residual compressive stress layer, significantly improving fatigue strength and resistance to stress corrosion. The areas adjacent to the internal thread structure within aerospace components require high surface roughness and precise dimensions to meet the product's sealing characteristics. However, traditional shot peening equipment is mostly designed for planar or external surfaces, lacking specialized devices for complex internal cavities such as internal threads. Internal threads are closed or semi-open structures; under traditional shot peening methods, shot cannot evenly cover stress concentration areas such as the tooth root and flank, resulting in insufficient shot peening intensity and coverage, affecting the shot peening effect. The geometric characteristics of the thread, such as pitch and tooth angle, require a high degree of adaptation to the shot peening method; otherwise, local over-peening or under-peening can easily occur, even leading to deformation. Furthermore, there is currently a lack of customized parameter systems for shot-peened parts with different internal threads, resulting in poor process adaptability. Therefore, a shot peening device and method specifically designed for the internal thread structure of aerospace components is needed. Summary of the Invention
[0003] The purpose of this invention is to propose a shot peening strengthening device and method for the internal thread structure of aerospace parts, effectively solving the technical difficulties of shot peening the internal threads of aerospace parts and meeting the design requirements of drawings. This shot peening strengthening device features good protective effect, short changeover and adjustment time, and long service life, and can meet the production mode of multiple varieties and small batches of aerospace parts. This shot peening strengthening method should feature good shot peening uniformity, high processing efficiency, wide engineering applicability, and stable and reliable quality, ensuring timely delivery of aerospace products.
[0004] The technical solution of this invention: A shot peening strengthening device for internal threads of aerospace parts includes a shot peening cover plate 2, a shot peening washer 3, a shot peening plug 4, a rod 6, a shot peening outer cover 7, a shot peening base 8, and a shot peening machine worktable 9. The shot peening washer 3 is disposed on the upper end face of the shot peening part, the shot peening cover plate 2 is disposed on the outer edge of the shot peening washer 3, and the shot peening washer 3 is provided with a through hole for the shot gun 1 to pass through. One end of the rod 6 is connected to the shot peening cover plate 2, and the other end is connected to the shot peening machine worktable 9. The shot peening base 8 is installed on the shot peening machine worktable 9, the shot peening plug 4 is installed inside the shot peening part 5, and the shot peening outer cover 7 is connected to the shot peening cover plate 2 and installed on the shot peening machine worktable 9.
[0005] Furthermore, the bottom of the shot peening cover plate 2 is provided with several slots evenly distributed along the circumference, which are installed in conjunction with the corresponding number of rods to fix the upper end of the rods to the shot peening cover plate; the shot peening machine worktable is provided with several through-hole slots evenly distributed along the diameter direction, the number of through-hole slots is the same as the number of slots, and the positions correspond one-to-one. The through-hole slots are installed in conjunction with the corresponding number of rods to fix the lower end of the rods to the shot peening machine worktable 9.
[0006] Furthermore, the lower end of rod 6 is a locking pin structure, which is inserted into the through hole slot of the shot peening machine's worktable. By adjusting the depth of the locking pin inserted into the through hole slot, it can be adapted to shot peening parts of different heights.
[0007] Furthermore, the center lines of the shot peening plug, shot peening cover plate, shot peening washer, multiple rods, shot peening cover, shot peening base, shot peening machine workbench, shot peening plug, and shot peening parts coincide.
[0008] Furthermore, the outermost diameter of the shot peening plug fits tightly against the inner wall below the relief groove of the shot peening part.
[0009] Furthermore, the upper edge of the shot peening plug is provided with a bevel, which fits into the transition fillet below the relief groove; the inner wall of the shot peening plug is provided with a radial groove.
[0010] Furthermore, the shot peening plug is made of nylon.
[0011] An installation method for the device involves inserting the shot peening plug 4 into the shot peening part 5 along its internal thread. During installation, ensure that the distance between the maximum outer diameter of the shot peening plug 4 and the inner wall of the shot peening part 5 is uniform. Slowly insert the plug until the bottom of the shot peening plug 4 is completely fitted with the bottom of the inner hole of the shot peening part 5. At the same time, ensure that the beveled surface of the upper edge of the shot peening plug fits with the transition fillet below the internal thread relief groove of the shot peening part 5, and that the shot peening plug 4 does not deviate. Install the shot peening base 8 on the shot peening machine worktable 9, and install the shot peening part 5 on the shot peening base 8, ensuring that the internal thread of the shot peening part 5 is horizontal relative to the shot peening machine worktable 9. Install the shot peening washer 3 onto the shot peening part 5, ensuring that their center lines coincide; Multiple rods 6 are installed at their upper ends in the slots evenly distributed on the shot peening cover plate 2, ensuring that the top of the rods 6 fits tightly against the bottom of the shot peening cover plate and that the height of the rods 6 is uniform. Align the shot peening cover plate 2 with the shot peening washer 3, and at the same time align the lower end of the rod 6 on the shot peening cover plate 2 with the through hole slot of the shot peening machine worktable 9, and install it downwards. Install the shot peening cover plate 2 on the step of the shot peening washer 3, and install the lower end of the rod 6 on the shot peening machine worktable 9. Ensure that the lower end of the rod 6 is inserted into the through hole slot of the shot peening machine worktable 9 to a uniform depth, and ensure that the shot peening cover plate 2 and the shot peening washer 3 fit tightly without gaps. The shot peening cover 7 is installed on the shot peening machine worktable 9 along the outer circle of the shot peening cover plate 2, and the shot peening cover 7 is tightly fitted to the shot peening cover plate 2; After the above process is completed, the center lines of the shot peening parts 5, shot peening plug 4, shot peening cover 2, shot peening washer 3, multiple rods 6, shot peening cover 7, shot peening base 8, and shot peening machine worktable 9 should coincide, and the above components can rotate together along the center of the shot peening machine worktable.
[0012] A shot peening strengthening method for the internal threads of aerospace parts is disclosed, implemented using the aforementioned apparatus. The shot peening gun 1 of the shot peening machine is aligned with the centerline of the part being peened. The gun moves vertically up and down at a speed of 20 mm / s, with a shot spray angle of 90°. The shot peening pressure of the shot peening machine is 0.45 MPa, the shot flow rate is 2.5 kg / min, and the rotation speed of the shot peening machine's worktable is 12 R / min. The highest point of the shot peening gun's vertical movement is higher than the highest point of the internal thread, and the lowest point is lower than the lowest point of the internal thread. The distance between the highest and lowest points of the shot peening gun is a fixed value of 40 mm. One cycle consists of the shot peening gun moving from the highest point to the lowest point and back again, with two cycles in total. n The number of times is given, where n is the number of data points on the shot peening saturation curve.
[0013] Technical effects of the present invention: This invention provides a shot peening strengthening device and method for the internal thread structure of aerospace parts, effectively solving the technical difficulties of shot peening internal threads of aerospace parts, meeting the design requirements of drawings, and significantly improving the fatigue life strength and stress corrosion resistance of aerospace parts. This shot peening strengthening device offers good protection, short changeover and adjustment time, and long service life, meeting the needs of multi-variety, small-batch production of aerospace parts. This shot peening strengthening method provides good shot peening uniformity, high processing efficiency, wide engineering applicability, and stable and reliable quality, ensuring timely delivery of aerospace products. Specifically, it includes the following advantages: 1) By using shot peening washers, shot peening plugs, rods, and shot peening bases of different sizes to match different shot peening parts, the rest of the structure does not need to be modified. The tooling is widely used, reducing tooling changeover time and tooling costs.
[0014] 2) The through-hole fitting rod on the shot peening machine worktable allows the shot peening cover plate and shot peening washer to be pressed onto the shot peening parts by gravity, so that the shot peening parts are stable and do not shake during the shot peening process, and the protection effect is good.
[0015] 3) The center lines of all components, including the shot peening plug, shot peening cover, shot peening washer, rod, shot peening cover, shot peening base, shot peening machine worktable, shot peening plug, and shot peening parts, are aligned, so that each component rotates along the same center line during the shot peening process, making the shot peening strengthening effect more uniform.
[0016] 4) The shot peening plug fits tightly against the inner wall of the shot peening part, preventing shot and dust from entering the part; the chamfer of the upper edge of the shot peening plug fits with the transition fillet below the relief groove, protecting the transition fillet, providing good protection and ensuring good quality stability during the shot peening process.
[0017] 5) The shot peening gasket, shot peening cover plate, and rod can be assembled into a single structure and directly installed on the parts; The shot peening plug has a groove in the middle hole, which makes it easy to remove from the inside of the part and facilitates tooling operation.
[0018] 6) The shot peening plug is made of nylon, which has good wear resistance and improves the tooling life.
[0019] 7) The shot peening pressure and shot flow rate are used together to achieve the highest and most stable shot peening intensity and good processability.
[0020] 8) The four parameters of the distance between the highest and lowest points of the spray gun, the speed of the spray gun movement, the rotation speed of the shot peening machine table, and the number of cycles are used in combination to achieve uniform coverage and stable shot peening intensity for the parts, which significantly improves the fatigue life, strength and stress corrosion resistance of aerospace parts. Attached Figure Description
[0021] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0022] Figure 1 This is a schematic diagram of an embodiment of a shot peening and strengthening device for internal threads of aerospace parts provided by the present invention; Figure 2 This is a schematic diagram of a shot peening cover plate according to an embodiment of a shot peening strengthening device for internal threads of aerospace parts provided by the present invention. Figure 3 This is a schematic diagram of a rod from an embodiment of a shot peening and strengthening device for internal threads of aerospace parts provided by the present invention; Figure 4 This is a schematic diagram of a shot peening plug according to an embodiment of a shot peening strengthening device for internal threads of aerospace parts provided by the present invention.
[0023] Among them, 1. shot peening gun, 2. shot peening cover plate, 3. shot peening gasket, 4. shot peening plug, 5. shot peening parts, 6. rod, 7. shot peening cover, 8. shot peening machine base, 9. shot peening machine worktable. Detailed Implementation
[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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, 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.
[0025] The features and illustrative embodiments of various aspects of the present invention will now be described in detail. Numerous specific details are set forth in the following detailed description to provide a thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention may be practiced without requiring some of these specific details. The following description of embodiments is merely intended to provide a better understanding of the invention by illustrating examples of the invention. The invention is by no means limited to any specific setups and methods set forth below, but covers any improvements, substitutions, and modifications to structures, methods, and devices without departing from the spirit of the invention. Well-known structures and techniques are not shown in the drawings and the following description to avoid unnecessarily obscuring the invention.
[0026] It should be noted that, unless otherwise specified, the embodiments of the present invention and the features thereof can be combined with each other, and the various embodiments can be referenced and cited in each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.
[0027] One embodiment of the present invention provides a shot peening strengthening device for internal threads of aerospace parts, the structural schematic diagram of which is shown below. Figure 1 .
[0028] The assembly includes a shot peening cover plate 2, a shot peening washer 3, a shot peening plug 4, rods 6, a shot peening outer cover 7, a shot peening base 8, and a shot peening machine worktable 9. The shot peening washer 3 is mounted on the shot peening cover plate 2, the shot peening cover plate 2 is connected to four rods 6, the four rods 6 are mounted on the shot peening machine worktable 9, the shot peening base 8 is mounted on the shot peening machine worktable 9, the shot peening outer cover 7 is connected to the shot peening cover plate 2 and mounted on the shot peening machine worktable 9, and the shot peening plug 4 is installed inside the shot peening component 5.
[0029] The shot peening washer 3 is installed on the upper surface of the shot peening part 5 through a stepped hole, so that the shot peening washer 3 and the center line of the shot peening part 5 coincide. The purpose is to make the shot peening washer 3 and the shot peening part 5 rotate along the same center line during the shot peening process.
[0030] The bottom of the shot peening cover plate 2 is provided with four slots evenly distributed along the circumference, which are installed in conjunction with the corresponding number of rods 6. Rods 6 of different lengths can be set on the same shot peening cover plate 2, so that the shot peening cover plate 2 can be placed horizontally and stably on the shot peening washer 3.
[0031] The bottom of the rod 6 is equipped with a locking pin of a certain length, which is inserted into the slot of the shot peening machine worktable 9. The height of the shot peening cover plate 2 relative to the shot peening machine worktable 9 is adjusted by adjusting the depth of the locking pin inserted into the slot. The purpose is to make the shot peening cover plate 2 and the shot peening washer 3 fit against the upper surface of the shot peening part 5 and press it onto the shot peening part 5 by their own weight, so that the shot peening part is stably placed on the shot peening machine worktable 9.
[0032] The shot peening machine worktable 9 is provided with four through-hole slots evenly distributed along the diameter direction, which are installed in conjunction with the corresponding number of rods 6 to ensure that the center lines of the shot peening machine worktable 9, the four rods 6, and the shot peening cover plate 2 coincide. The purpose is to make the shot peening machine worktable 9, the four rods 6, and the shot peening cover plate 2 rotate along the same center line during the shot peening process.
[0033] The shot peening base 8 is installed on the shot peening machine worktable 9. The shot peening part 5 is placed on the shot peening base 8 through the lower inner hole, so that the inner thread of the shot peening part 5 is horizontal relative to the shot peening machine worktable. The purpose is to make the bottom of the shot peening part 5 stably placed on the shot peening machine worktable 9. The shape of the shot peening base 8 can be adjusted to suit different irregular shot peening parts 5.
[0034] The shot peening plug 4 is installed below the internal thread relief groove inside the shot peening part 5. The bottom of the shot peening plug 4 is in contact with the bottom of the shot peening part 5, and the circumferential chamfer of the upper edge of the shot peening plug 4 is in contact with the transition fillet below the internal thread relief groove of the shot peening part 5. The purpose is to prevent the shot ejected during the shot peening process from entering the interior of the shot peening part 5 through the gap between the shot peening part 5 and the shot peening plug 4, thereby avoiding the generation of foreign matter.
[0035] Among them, the center lines of the shot peening parts, shot peening plugs, shot peening covers, shot peening washers, rods, shot peening covers, shot peening bases, and shot peening machines are aligned so that each part rotates along the same center line during the shot peening process.
[0036] The second embodiment of the present invention provides an installation and usage method for a shot peening strengthening device for internal threads of aerospace parts: Insert the shot peening plug 4 into the shot peening part 5 along the internal thread. During installation, ensure that the distance between the maximum outer circle of the shot peening plug 4 and the inner wall of the shot peening part 5 is uniform. Slowly insert it until the bottom of the shot peening plug 4 is completely in contact with the bottom of the inner hole of the shot peening part 5. At the same time, ensure that the circumferential chamfer of the upper edge of the shot peening plug is in contact with the transition fillet below the internal thread relief groove of the shot peening part 5, and that the height of the shot peening plug 4 is uniform and consistent without any offset. Install the shot peening base 8 on the shot peening machine worktable 9, and install the shot peening part 5 on the shot peening base 8, ensuring that the internal thread of the shot peening part 5 is horizontal relative to the shot peening machine worktable 9. Install the shot peening washer 3 on the shot peening part 5, ensuring that the center lines of the two coincide. The inner diameter of the shot peening washer 3 is 2mm smaller than the nominal diameter of the inner thread of the shot peening part 5. This ensures that the shot will not be sprayed onto the upper surface of the shot peening part 5 during the shot peening process without affecting the movement of the spray gun. Four rods 6 are installed in evenly distributed grooves on the shot peening cover plate 2, ensuring that the top of the rods 6 fits tightly against the bottom of the shot peening cover plate and that the height of the four rods 6 is uniform. Align the shot peening cover plate 2 with the shot peening washer 3, and at the same time align the rod 6 on the shot peening cover plate 2 with the slot of the shot peening machine worktable 9. Then install it downwards, install the shot peening cover plate 2 on the shot peening washer 3, and install the rod 6 on the shot peening machine worktable 9. Ensure that the rod 6 is inserted into the slot of the shot peening machine worktable 9 at a uniform depth, and ensure that the shot peening cover plate 2 and the shot peening washer 3 fit tightly without gaps. The shot peening cover 7 is installed on the shot peening machine worktable 9 along the outer circle of the shot peening cover plate 2. The shot peening cover 7 is of uniform height and fits tightly with the shot peening cover plate 2. After the above process is completed, the center lines of shot peening parts 5, shot peening plug 4, shot peening cover 2, shot peening washer 3, four rods 6, shot peening cover 7, shot peening base 8, and shot peening machine worktable 9 should coincide, and the above components can rotate together around the center of the shot peening machine worktable. After a part has been shot peened, clean the dust and residual shot from the surface of the shot peening device, lift the shot peening cover 7 upwards, then lift the shot peening cover plate 2 and rod 6, then lift the shot peening washer 3 and shot peening part 5, clean the shot and dust inside the shot peening part 5, remove the shot peening plug 4 after cleaning, and then clean the shot peening plug 4; then replace the part and repeat the above installation steps to shot peening the next part.
[0037] A third embodiment of the present invention provides a method for shot peening internal threads of a part using the aforementioned shot peening strengthening apparatus for internal threads of aerospace parts.
[0038] Based on the structure and size of the internal thread, ASH70 cast steel shot was selected. The shot can evenly hit the tooth flank and tooth root of the thread, so that all parts of the internal thread can get good coverage and shot peening intensity. The nozzle of the shot peening gun is a 45° reflective nozzle. The center line of the shot stream is at a 90° angle to the internal thread of the shot-peened part. The purpose is to ensure that the shot hits the root of the thread perpendicularly during the shot peening process.
[0039] Based on the structure of the spray gun and the required shot peening intensity, the shot peening pressure is set to 0.45 MPa and the shot flow rate is set to 2.5 kg / min. The shot peening pressure and shot flow rate are used in combination. If the shot peening pressure is too high, the shot flow rate will not be enough to provide a uniform shot flow, resulting in unstable shot peening intensity. If the shot flow rate is too high, the shot peening pressure will not be enough to give the shot sufficient kinetic energy, which will also result in unstable shot peening intensity. Only when the shot peening pressure and shot flow rate are in the optimal ratio can the most stable and highest shot peening intensity be obtained.
[0040] During shot peening, the shot blasting gun is positioned vertically at the center line of the shot peening machine's worktable. During shot peening, the gun moves vertically at a uniform speed, with the highest point higher than the highest point of the internal thread and the lowest point lower than the lowest point. The distance between the highest and lowest points is 40mm, greater than the height of the internal thread. The gun's moving speed is 20mm / s. The shot peening machine's worktable rotates the peened part at a uniform speed around its center, with a rotation speed of 10R / s. The combined use of the gun's moving speed and the worktable's rotation speed ensures that the shot trajectory on the part's internal thread is different during each shot peening cycle, resulting in uniform shot peening across all parts of the internal thread. The number of cycles is set to 32, providing sufficient time for shot peening to achieve 100% coverage. The distance between the highest and lowest points, the gun's moving speed, the worktable's rotation speed, and the number of cycles are used in combination to ensure uniform coverage and stable shot peening intensity, and to generate a suitable saturation curve by controlling the number of cycles.
[0041] In summary, the present invention has the following characteristics: (1) The present invention provides a shot peening strengthening device for internal threads of aerospace parts, including a shot peening plug; a shot peening cover plate; a shot peening washer; a rod; a shot peening cover; a shot peening base; a shot peening machine worktable; the shot peening washer is installed on the shot peening cover plate, the shot peening cover plate is connected to the rod, the rod is installed on the shot peening machine worktable, the shot peening base is connected to the shot peening part and installed on the shot peening machine worktable, the shot peening cover is connected to the shot peening cover plate and installed on the shot peening machine worktable, and the shot peening plug is installed inside the shot peening part.
[0042] (2) The shot peening gasket includes multiple shot peening gaskets of different sizes, which are matched with different shot peening parts. The shot peening gasket is installed on the shot peening part to protect the upper end face of the shot peening part so that the shot peening part is not hit by shot during the shot peening strengthening process.
[0043] (3) The bottom of the shot peening cover plate is provided with several slots evenly distributed along the circumference, which are used to install the corresponding number of rods to fix the rods on the shot peening cover plate.
[0044] (4) The shot peening machine workbench is provided with several through-hole slots evenly distributed along the diameter direction, which are installed in conjunction with the corresponding number of rods.
[0045] (5) The bottom of the rod is provided with a certain length of locking pin, which is inserted into the slot of the shot peening machine worktable. By adjusting the depth of the locking pin inserted into the slot, it can be adapted to shot peening parts of different heights.
[0046] (6) The shot peening base includes multiple shot peening bases of different sizes, which are matched with different shot peening parts. The shot peening base is installed on the shot peening machine worktable so that the internal thread of the shot peening part is in a horizontal position relative to the shot peening machine worktable.
[0047] (7) The center lines of the shot peening plug, shot peening cover, shot peening washer, rod, shot peening cover, shot peening base, shot peening machine workbench, shot peening plug, and shot peening parts are coincident.
[0048] (8) The shot peening plug includes multiple shot peening plugs of different sizes, which are installed inside the shot peening part. The largest outer circle of the plug is tightly fitted with the inner wall below the relief groove of the shot peening part, so that the shot and dust and other foreign matter in the shot peening process cannot enter the part.
[0049] (9) The upper edge of the shot peening plug is designed with a circumferential bevel that fits with the transition fillet below the relief groove, so that the transition fillet is not hit by the shot during the shot peening process.
[0050] (10) A groove is designed in the middle hole of the shot peening plug to facilitate the operator to remove the shot peening plug from the inside of the part by hand.
[0051] (11) A moving space for the spray gun is provided below the shot peening plug, so that the spray gun can move into the part for more uniform shot peening. At the same time, the space stores the sprayed shot, preventing the shot from entering the contact area between the shot peening plug and the shot peening part.
[0052] (12) The shot peening plug is made of nylon, which has good wear resistance and is not easily worn or deformed after long-term shot peening strengthening process; the material is softer than the shot peening parts, which prevents the shot peening parts from being scratched during use.
[0053] (13) The shot peening strengthening process method matching the shot peening strengthening process device for internal threads of aerospace parts provided by the present invention uses ASH70 cast steel shot. The shot peening gun of the shot peening machine coincides with the center line of the shot peening part. The shot peening gun moves vertically up and down. The moving speed of the shot peening gun is 20mm / s. The shot spraying angle is 90°. The shot peening pressure of the shot peening machine is 0.45MPa. The shot flow rate of the shot peening machine is 2.5kg / min. The rotation speed of the shot peening machine worktable is 12R / min. The highest point of the shot peening gun in the vertical direction is higher than the highest point of the internal thread, and the lowest point is lower than the lowest point of the internal thread. The distance between the highest point and the lowest point of the shot peening gun is a fixed value of 40mm. The shot peening gun moves from the highest point to the lowest point and back from the lowest point to the highest point, which is one cycle. The number of cycles is 32.
[0054] In summary, the shot peening strengthening device and method for internal threads of aerospace parts provided by this invention effectively solves the technical difficulties of shot peening internal threads of aerospace parts, meets the design requirements of drawings, and significantly improves the fatigue life strength and stress corrosion resistance of aerospace parts. This shot peening strengthening device offers good protection, short changeover adjustment time, and long service life, meeting the needs of multi-variety, small-batch production of aerospace parts. This shot peening strengthening method provides good uniformity of shot peening, high processing efficiency, wide engineering applicability, and stable and reliable quality, ensuring timely delivery of aerospace products.
[0055] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should be covered within the protection scope of the present invention.
Claims
1. A shot peening and strengthening device for internal threads of aerospace parts, characterized in that, The assembly includes a shot peening cover plate, a shot peening washer, a shot peening plug, a rod, a shot peening outer cover, a shot peening base, and a shot peening machine worktable. The shot peening washer is located on the upper surface of the shot peening part, and the shot peening cover plate is located on the outer edge of the shot peening washer. The shot peening washer has a through hole for the shot gun to pass through. One end of the rod is connected to the shot peening cover plate, and the other end is connected to the shot peening machine worktable. The shot peening base is installed on the shot peening machine worktable, the shot peening plug is installed inside the shot peening part, and the shot peening outer cover is connected to the shot peening cover plate and installed on the shot peening machine worktable.
2. The shot peening and strengthening device for internal threads of aerospace parts according to claim 1, characterized in that, The bottom of the shot peening cover plate is provided with several slots evenly distributed along the circumference, which are installed in conjunction with the corresponding number of rods to fix the upper end of the rods to the shot peening cover plate; the shot peening machine worktable is provided with several through-hole slots evenly distributed along the diameter direction, the number of through-hole slots is the same as the number of slots, and the positions correspond one-to-one. The through-hole slots are installed in conjunction with the corresponding number of rods to fix the lower end of the rods to the shot peening machine worktable.
3. The shot peening and strengthening device for internal threads of aerospace parts according to claim 1, characterized in that, The lower end of the rod has a locking pin structure, which is inserted into the through hole slot of the shot peening machine's worktable. By adjusting the depth of the locking pin inserted into the through hole slot, it can be adapted to shot peening parts of different heights.
4. The shot peening and strengthening device for internal threads of aerospace parts according to claim 2, characterized in that, Shot peening plug, shot peening cover plate, shot peening washer, multiple rods, shot peening cover, shot peening base, shot peening machine workbench, shot peening plug, center line coincidence of shot peening parts.
5. The shot peening and strengthening device for internal threads of aerospace parts according to claim 1, characterized in that, The outermost diameter of the shot peening plug fits tightly against the inner wall below the relief groove of the shot peening part.
6. The shot peening and strengthening device for internal threads of aerospace parts according to claim 1, characterized in that, The upper edge of the shot peening plug is provided with a bevel, which fits with the transition fillet below the relief groove; the inner wall of the shot peening plug is provided with a radial groove.
7. The shot peening and strengthening device for internal threads of aerospace parts according to claim 1, characterized in that, The shot peening plug is made of nylon.
8. A method for installing the device as described in any one of claims 1-7, characterized in that, Insert the shot peening plug into the shot peening part along the internal thread. During installation, ensure that the distance between the maximum outer diameter of the shot peening plug and the inner wall of the shot peening part is uniform. Slowly insert it until the bottom of the shot peening plug is completely in contact with the bottom of the inner hole of the shot peening part. At the same time, ensure that the bevel of the upper edge of the shot peening plug is in contact with the transition fillet below the relief groove of the internal thread of the shot peening part, and that the shot peening plug does not shift. Install the shot peening base on the shot peening machine worktable, and install the shot peening parts on the shot peening base, ensuring that the internal threads of the shot peening parts are horizontal relative to the shot peening machine worktable. Install the shot peening gasket onto the shot peening part, ensuring that their center lines coincide; Multiple rods are installed at their upper ends in the evenly distributed grooves on the shot peening cover plate, ensuring that the top of the rod fits tightly against the bottom of the shot peening cover plate and that the height of the rod is uniform. Align the shot peening cover plate with the shot peening washer, and at the same time align the lower end of the rod on the shot peening cover plate with the through hole slot of the shot peening machine worktable. Install it downwards, install the shot peening cover plate on the step of the shot peening washer, and install the lower end of the rod on the shot peening machine worktable. Ensure that the lower end of the rod is inserted into the through hole slot of the shot peening machine worktable to a uniform depth, and ensure that the shot peening cover plate and the shot peening washer fit tightly without gaps. Install the shot peening cover along the outer circle of the shot peening cover plate on the shot peening machine worktable, and ensure that the shot peening cover fits tightly against the shot peening cover plate; After the above process is completed, the center lines of the shot peening parts, shot peening plugs, shot peening cover plates, shot peening washers, multiple rods, shot peening covers, shot peening bases, and shot peening machine worktables should coincide, and all the above components can rotate together around the center of the shot peening machine worktables.
9. A shot peening strengthening method for internal threads of aerospace parts, implemented using the apparatus described in any one of claims 1-7, characterized in that, The shot peening gun of the shot peening machine is aligned with the centerline of the part being shot peened. The gun moves vertically up and down at a speed of 20 mm / s. The shot spray angle is 90°. The shot peening pressure is 0.45 MPa, the shot flow rate is 2.5 kg / min, and the rotation speed of the shot peening machine's worktable is 12 R / min. The highest point of the shot peening gun's vertical movement is higher than the highest point of the internal thread, and the lowest point is lower than the lowest point of the internal thread. The distance between the highest and lowest points of the shot peening gun is a fixed value of 40 mm. One cycle consists of the shot peening gun moving from the highest point to the lowest point and back again. The number of cycles is 2. n The number of times is given, where n is the number of data points on the shot peening saturation curve.