A shot peening method for correcting out-of-tolerance chordal shape of panel-type parts

Abstract

This invention belongs to the field of shot peening forming technology and discloses a shot peening correction method for out-of-tolerance chordal shape of panel-type parts. The method includes the following steps: dividing the panel thickness zone; measuring the out-of-tolerance data and drawing an out-of-tolerance chart; determining the shot peening correction area based on the degree of out-of-tolerance; determining the shot peening correction machine parameters based on the panel thickness and out-of-tolerance data; providing pre-shot peening protection to the non-shot peening areas of the part; and shot peening correction using the machine tool. This invention solves the technical problems of low efficiency, low accuracy, and reliance on manual experience in existing correction methods. It achieves accurate identification and correction of out-of-tolerance chordal shape of panel parts.

Description

Technical Field

[0001] This invention application belongs to the field of shot peening forming technology, specifically relating to a shot peening correction method for panel-type parts with out-of-tolerance chordal shape. Background Technology

[0002] As a crucial component of aircraft structure, the manufacturing quality of wing panels directly impacts aircraft safety and flight life. Shot peening, an advanced specialized sheet metal processing technology, plays a key role in wing panel manufacturing. This technology uses high-speed jets of tiny shot to precisely impact the metal surface, inducing plastic deformation in the material's surface layer. This allows for the precise forming of complex shapes while simultaneously enhancing the material's strength and fatigue life.

[0003] However, the complexity of shot peening technology cannot be ignored. The key lies in precisely controlling a series of interrelated process parameters to ensure the stability of the forming process and the accuracy of the results. These parameters include, but are not limited to, shot peening pressure, shot size, blasting angle, and shot peening speed. The selection and control of these parameters not only require extremely high technical precision but also necessitate consideration of material properties, panel structural characteristics, and final forming requirements. Any minute deviation can significantly impact the forming accuracy.

[0004] In practical applications, due to the interrelationships and constraints among these process parameters, it is often necessary to determine the optimal parameter combination through extensive experimentation and optimization. However, even with such efforts, it is still difficult to completely avoid forming defects caused by improper parameter settings, such as out-of-tolerance chordal shapes of the panel. Typically, addressing these issues relies heavily on manual experience to perform multiple trial-and-error corrections, which is not only inefficient and costly but also fails to guarantee consistent forming quality. Furthermore, due to the inaccuracy of correction, manual shaping by workers is still required, which not only demands a high level of skill from workers but also further increases manufacturing costs and uncertainty.

[0005] To overcome these limitations, it is necessary to develop a more accurate and efficient calibration method to precisely identify and correct deviations in the chordal shape of paneling. This invention is based on this urgent need, providing a reliable parameter selection method for addressing the problem of deviations in the chordal shape of paneling, improving the stability and accuracy of calibration results, and also helping to reduce manufacturing costs, increase production efficiency, and promote the further development and widespread application of shot peening technology. Summary of the Invention

[0006] This invention application addresses the technical problems of low efficiency, low accuracy, and reliance on manual experience in existing shaping methods by proposing a shot peening method for correcting out-of-tolerance chordal shapes of panel-type parts. This method enables accurate identification and correction of out-of-tolerance chordal shapes of panel parts.

[0007] To achieve the aforementioned objectives, the technical solution adopted in this application is as follows:

[0008] A shot peening method for correcting outdated chordal shape of panel-type parts, comprising the following steps:

[0009] Step 1: Divide the wall panel thickness zone;

[0010] Step 2: Measure the out-of-tolerance data and draw a chart showing the out-of-tolerance of the panel shape;

[0011] Step 3: Determine the shot peening correction area based on the degree of deviation;

[0012] Step 4: Determine the parameters of the shot peening and straightening machine based on the wall panel thickness and out-of-tolerance data;

[0013] Step 5: Perform pre-shot peening protection on non-shot peening areas of the parts;

[0014] Step 6: Shot peening and alignment of the machine tool.

[0015] As a further aspect of the present invention: Step 1 specifically involves: performing geometric analysis on the wing panel to divide the panel into a thickness zone of less than 2 mm, a thickness zone of 2 to 5 mm, and a thickness zone of more than 5 mm.

[0016] As a further aspect of the present invention: Step 2 specifically involves: placing the wing panel with out-of-tolerance chordal shape after shot peening onto a tooling fixture, recording the maximum gap between the panel and the template at the contour boundary of each rib, as well as the location of the fitting area, and drawing a chart of out-of-tolerance chordal shape; a chordal template is provided at each rib on the tooling fixture, and its shape fits the theoretical chordal shape of the panel.

[0017] As a further aspect of the present invention: Step 3 specifically involves: determining the length range of the wall panel's out-of-tolerance shape using a tooling fixture, which is the shot peening correction length range, and the width range being the entire width of the wall panel, excluding the wall panel edge depression area where the thickness differs from the surrounding web plate by more than 2mm.

[0018] As a further aspect of the present invention: In step 4, the shot medium is selected based on the maximum deviation of the wall plate thickness and the external clearance, specifically as follows:

[0019] When the wall panel thickness is greater than 5mm, large-size shot can be used (the type of shaped shot should be consistent with the type of tangential shot peening).

[0020] When the wall panel thickness is between 2 and 5 mm, the shot medium is determined based on the maximum deviation of the gap in the wall panel thickness. When the maximum deviation is greater than 5 cm, large-size shot can be used (the type of correcting shot is consistent with the type of tangential shot peening); when the maximum deviation is greater than 2 cm but less than 5 cm, small-size shot can be used (the type of correcting shot is consistent with the type of tangential shot peening); when the maximum deviation is less than 2 cm, manual shot peening is performed using an ultrasonic correction machine.

[0021] When the wall panel thickness is less than 2mm, manual shot peening with a rotary blade is used for shaping. The rotary blade shot peening speed is generally 5000-6500r / min.

[0022] As a further aspect of the present invention: the shot peening pressure of the large-size shot is generally selected to be 0.6 to 0.9 times the tangential shot peening forming pressure, and the shot peening pressure of the small-size shot is generally selected to be 1 to 1.5 times the tangential shot peening forming pressure; the shot peening speed of the machine tool is selected to be 6 to 10 m / min.

[0023] As a further aspect of the present invention: Step 5 specifically involves protecting the edges of unreinforced wall panels, thin web areas with a thickness of less than 2 mm, and web depression areas with a thickness difference of more than 2 mm from the surrounding webs. For reinforced wall panels, the top of the vertical reinforcement, the root R area, web depression areas, and edges need to be protected.

[0024] As a further embodiment of the present invention: Step 6 specifically involves: suspending and clamping the wall panel onto the machine tool fixture, with the front beam of the part facing upwards and the rear beam facing downwards, ensuring that the ribbed wall panel maintains horizontal ribs, clamping in a free state, without applying prestress, and performing reverse shot peening on the correction area using predetermined shot peening parameters.

[0025] Compared with the prior art, the beneficial effects of this application are:

[0026] 1. This invention achieves precise correction of the chordal shape of the panel by more accurately controlling the shot peening and shaping parameters, thereby reducing rework and scrap caused by insufficient forming accuracy and thus reducing production costs.

[0027] 2. Traditional methods often rely on experience-based adjustments and repeated trial and error, requiring a high level of operator experience. This invention reduces reliance on manual experience, minimizes production delays and cost increases due to insufficient experience, and improves the stability and reliability of the production process.

[0028] 3. By accurately identifying the degree of deviation of the wall panel and controlling the shot peening and shaping parameters, this invention reduces the multiple trial and error processes caused by improper selection of shaping parameters, thereby shortening the production cycle and improving production efficiency.

[0029] 4. In summary, this invention offers numerous advantages, including improved production efficiency, enhanced forming accuracy, and reduced reliance on manual experience, significantly lowering manufacturing costs compared to existing technologies. These advantages give this invention broad application prospects and market competitiveness in the aerospace manufacturing industry.

[0030] The present application will be further described below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0031] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof.

[0032] In the attached diagram:

[0033] Figure 1 This is a schematic diagram of thickness partitioning for wall panel-type parts provided in an embodiment of the present invention;

[0034] Figure 2 This is a schematic diagram of the wall panel-type parts and tooling frame provided in an embodiment of the present invention;

[0035] Figure 3 This is a schematic diagram illustrating the out-of-tolerance chordal shape of a wall panel part provided in an embodiment of the present invention.

[0036] The numbers in the diagram are explained as follows: 1. Wire template; 2. Wall panel whose wire shape fits the template after shot peening; 3. Wall panel whose wire shape exceeds the tolerance after shot peening. Detailed Implementation

[0037] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0038] The purpose of this invention is to provide a shot peening correction method for panel-type parts with out-of-tolerance chordal shape, which can solve the problem that improper selection of shot peening parameters leads to out-of-tolerance chordal shape after forming, affecting delivery.

[0039] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0040] This application uses a wall panel component as an example, where the thickness of the entire component varies within the range of 1 to 8 mm. For example... Figure 1 As shown, the specific steps are as follows:

[0041] Step 1: Divide the wall panel thickness zone.

[0042] A geometric analysis was performed on the wing panels, dividing them into three thickness zones: less than 2 mm, 2–5 mm, and greater than 5 mm. See Table 1 for details.

[0043] Table 1. Panel Thickness Zoning (Unit: mm)

[0044] rib 0～17 17～20 20～22 22～28 thickness Greater than 5 2～5 Greater than 5 Less than 2

[0045] Step 2: Measure the out-of-tolerance data and draw a chart showing the out-of-tolerance of the panel shape.

[0046] The out-of-tolerance wing panel, after shot peening, is placed on a tooling fixture. Each rib on the tooling fixture has a chordal template, such as... Figure 2 As shown, its shape fits the theoretical chordal shape of the panel. Record the maximum gap between the panel and the template at the contour boundary for each rib, as well as the location of the fitting area, and draw a shape deviation chart.

[0047] Table 2. Chart of out-of-tolerance dimensions of wall panels in the tangential direction (unit: cm)

[0048]

[0049]

[0050] Step 3: Determine the shot peening correction area based on the degree of deviation.

[0051] The shot peening surface is the inner surface of the wing panel. For areas where the panel thickness is less than 2mm, shot peening is not performed using a machine tool. The length range for shot peening is determined based on the thickness, from rib 0 to rib 22, and the width range is the entire width of the panel, excluding the recessed area at the panel edge where the thickness difference from the surrounding web is more than 2mm.

[0052] Step 4: Determine the parameters of the shot peening and straightening machine based on the wall panel thickness and out-of-tolerance data.

[0053] The selection of shot medium can be determined based on the maximum deviation of the wall plate thickness and the clearance between the outer ribs. For areas with a wall plate thickness greater than 5 mm, i.e., ribs 0 to 17 and 20 to 22, ASH460 shot is used for shot peening. For areas with a wall plate thickness between 2 and 5 mm, the shot medium is determined based on the maximum deviation of the clearance between the wall plate thickness and the outer ribs. For areas with a wall plate thickness less than 2 mm, manual shot peening with a rotary vane is used for shaping, with a rotary vane peening speed of 5000 r / min.

[0054] The shot peening pressure for ASH460 is selected as 0.8 times the tangential shot peening forming pressure, i.e., 0.12 MPa for 0-17 ribs and 0.16 MPa for 20-22 ribs. The shot peening pressure for ASH230 is selected as 1.2 times the tangential shot peening forming pressure, i.e., 0.16 MPa for 17-20 ribs.

[0055] The machine tool speed is selected as 6m / min.

[0056] Step 5: Perform pre-shot peening protection on the non-shot peening areas of the parts.

[0057] For unreinforced wall panels, the edges, thin web areas with a thickness of less than 2 mm, and web depression areas with a thickness difference of more than 2 mm from the surrounding webs need to be protected. For reinforced wall panels, the top of the vertical reinforcement, the R-zone of the reinforcement roots, web depression areas, and edges need to be protected.

[0058] Step 6: Shot peening and reshaping of the machine tool.

[0059] Hang the wall panel on the machine tool fixture with the front beam facing up and the rear beam facing down. Make sure the ribbed wall panel is kept horizontal. Clamp it in a free state without applying prestress. Use the predetermined shot peening parameters to perform reverse shot peening on the correction area.

[0060] Thus, the objective of this invention has been achieved.

[0061] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A shot peening method for correcting out-of-tolerance chordal shape of panel-type parts, characterized in that, Includes the following steps: Step 1: Divide the panel thickness zones; Through geometric analysis of the wing panels, divide the panels into zones with a thickness of less than 2 mm, a thickness of 2-5 mm, and a thickness of more than 5 mm. Step 2: Measure the out-of-tolerance data and draw the out-of-tolerance chart of the panel shape; place the wing panel with out-of-tolerance chordal shape after shot peening on the tooling fixture, record the maximum gap between the panel and the template at the contour boundary of each rib, as well as the location of the fitting area, and draw the out-of-tolerance chart; a chordal template is set at each rib on the tooling fixture, and its shape fits the theoretical chordal shape of the panel; Step 3: Determine the shot peening correction area based on the degree of deviation; determine the length range of the wall panel's shape deviation through the tooling fixture, which is the shot peening correction length range. The width range is the entire width of the wall panel, excluding the wall panel edge depression area where the thickness difference from the surrounding web plate is more than 2mm. Step 4: Determine the parameters of the shot peening and straightening machine based on the wall plate thickness and out-of-tolerance data; select the shot medium based on the maximum out-of-tolerance value of the wall plate thickness and the external clearance, specifically: When the wall panel thickness is greater than 5mm, use ASH460 shot. When the wall panel thickness is between 2 and 5 mm, the shot medium is determined based on the maximum deviation of the gap in the wall panel thickness. When the maximum deviation is greater than 5 cm, ASH460 shot is used; when the maximum deviation is greater than 2 cm but less than 5 cm, ASH230 shot is used; when the maximum deviation is less than 2 cm, an ultrasonic peening machine is used for manual shot peening. When the wall panel thickness is less than 2mm, manual shot peening with a rotary blade is used for shaping. The rotary blade shot peening speed is 5000-6500r / min. Step 5: Protect the non-shot-peened areas of the parts before shot peening; for unreinforced wall panels, protect the edges of the wall panels, thin web areas with a thickness of less than 2mm, and web depression areas with a thickness difference of more than 2mm from the surrounding webs; for ribbed wall panels, protect the top of the vertical ribs, the rib root R area, web depression areas, and edges. Step 6: Shot peening and alignment of the machine tool.

2. The shot peening method for correcting out-of-tolerance chordal shape of panel-type parts according to claim 1, characterized in that, In step 4, the shot peening pressure of the ASH460 projectile is selected to be 0.6 to 0.9 times the tangential shot peening forming pressure, and the shot peening pressure of the ASH230 projectile is selected to be 1 to 1.5 times the tangential shot peening forming pressure; the shot peening speed of the machine tool is selected to be 6 to 10 m / min.

3. A shot peening method for correcting out-of-tolerance chordal shape of panel-type parts according to claim 1 or 2, characterized in that, Step 6 specifically involves: suspending and clamping the wall panel onto the machine tool fixture, with the front beam of the part facing upwards and the rear beam facing downwards, keeping the ribs of the ribbed wall panel horizontal, clamping it in a free state, without applying prestress, and performing reverse shot peening on the correction area using predetermined shot peening parameters.

4. The shot peening method for correcting out-of-tolerance chordal shape of panel-type parts according to claim 1, characterized in that, The thickness zone division in step 1 is based on the ribs of the wall panel.

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