Hole wall reinforcement device and hole wall reinforcement method
By using the spinning head and spinning structure of the hole wall strengthening device, combined with forward and reverse spinning components, the problem of reaming loss during hole wall strengthening is solved, achieving better fatigue resistance and residual compressive stress distribution.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SHANGHAI AIRCRAFT MFG
- Filing Date
- 2026-05-07
- Publication Date
- 2026-06-05
AI Technical Summary
In the existing technology, the strengthening layer is lost during the reaming process, resulting in an unsatisfactory strengthening effect and a low level of residual compressive stress.
A hole wall strengthening device is adopted, including a positioning component, a spinning head and a driving component. The spinning structure on the spinning head squeezes the hole wall, and combined with the forward and reverse spinning components, uniform plastic deformation of the hole wall is achieved, avoiding reaming.
It improves the fatigue resistance of the hole wall, reduces material damage, enhances the uniformity of residual compressive stress distribution, and improves the hole wall quality and strengthening effect.
Smart Images
Figure CN122142679A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of surface strengthening technology, and in particular to a hole wall strengthening device and a hole wall strengthening method. Background Technology
[0002] In fields such as aerospace manufacturing, the area around connection holes in structural components is more prone to fatigue failure due to stress concentration. Therefore, surface strengthening of the hole walls is typically performed to generate residual compressive stress at the hole wall location, thereby improving the fatigue life around the connection holes.
[0003] In related technologies, cold expansion extrusion of the connecting hole wall is typically performed using a slotted mandrel and a support rod. During the strengthening process, the large contact area between the slotted mandrel and the hole wall results in excessive resistance, making it easier for material flow near the hole wall to cause residue or damage to the hole wall due to the slotted mandrel's opening position. Therefore, reaming is required after strengthening to eliminate residue and surface defects from the extrusion process. However, reaming results in the loss of the strengthening layer, affecting the strengthening effect. Furthermore, this method leads to a lower residual compressive stress level near the hole wall at the end of the connecting hole facing the slotted mandrel, resulting in an unsatisfactory strengthening effect. Summary of the Invention
[0004] The purpose of this invention is to provide a hole wall strengthening device and a hole wall strengthening method, which avoids the reaming process of the strengthening layer and improves the hole wall quality and strengthening effect.
[0005] This invention provides a hole wall strengthening device, comprising:
[0006] A positioning component is provided with a guide hole. The positioning component is used to connect with the workpiece and to make the axis of the guide hole coincide with the axis of the hole to be strengthened on the workpiece.
[0007] A spinning head, the axis of which coincides with the axis of the guide hole and is rotatable about the axis of the guide hole, the spinning head is provided with a spinning structure that extends along the axial direction of the spinning head, and the spinning structure is used to compress the hole wall of the hole to be strengthened;
[0008] A drive assembly, mounted on the positioning assembly, is capable of driving the spinning head to rotate about the axis of the guide hole.
[0009] As a preferred technical solution for the hole wall strengthening device, the spinning head includes an extrusion section and a spinning section. The extrusion section can guide the spinning section into the hole to be strengthened, and the spinning structure is disposed in the spinning section.
[0010] As a preferred technical solution for the hole wall strengthening device, the driving component can also drive the spinning head to move axially along the guide hole.
[0011] As a preferred technical solution for the hole wall strengthening device, the spinning structure includes a first spinning part and a second spinning part, and the outer surfaces of the first spinning part and the second spinning part are smoothly transitioned.
[0012] As a preferred technical solution for the hole wall strengthening device, when the spinning head rotates forward, the first spinning part is used to squeeze the hole wall of the hole to be strengthened; when the spinning head rotates in reverse, the second spinning part is used to squeeze the hole wall of the hole to be strengthened.
[0013] As a preferred technical solution for the hole wall strengthening device, the spinning structure is configured as a plurality of structures, which are spaced apart circumferentially along the spinning head.
[0014] As a preferred technical solution for the hole wall strengthening device, the positioning component includes a mold base and a positioning seat. The mold base is used to fix and connect with the workpiece, and the positioning seat is positioned and cooperates with the mold base. The positioning seat has the guide hole.
[0015] As a preferred technical solution for the hole wall strengthening device, it further includes a base and a housing. The base is fixedly connected to the positioning seat, and the housing is fixedly connected to the base. The base and the housing together form a receiving space for accommodating the driving component, and the driving component is installed in the receiving space.
[0016] This invention provides a method for strengthening pore walls, implemented using any of the pore wall strengthening devices described above, the method comprising:
[0017] Position the positioning component on the workpiece so that the axis of the guide hole coincides with the axis of the hole to be strengthened.
[0018] The drive assembly drives the spinning head to rotate around the axis of the guide hole and squeeze part of the hole wall to be strengthened.
[0019] As a preferred technical solution for hole wall strengthening, the driving component drives the spinning head to rotate around the axis of the guide hole and squeeze a portion of the hole wall to be strengthened, including:
[0020] The drive assembly drives the spinning head to rotate clockwise around the axis of the guide hole by a first preset angle;
[0021] The drive assembly causes the spinning head to reverse the axis of the guide hole by a second preset angle;
[0022] The drive assembly drives the spinning head to rotate clockwise around the axis of the guide hole by a third preset angle;
[0023] The sum of the first preset angle and the third preset angle equals the second preset angle.
[0024] The beneficial effects of this invention are as follows:
[0025] This invention provides a hole wall strengthening device. By protruding a spinning structure on the spinning head, only the spinning structure compresses the hole wall to be strengthened, reducing the resistance during the extrusion process of the spinning head. There is no need to set a slotted bushing. The spinning head is driven to rotate by a drive component to achieve surface strengthening of the entire hole wall. It can effectively control the cumulative plastic deformation of the hole wall, prevent damage to the hole wall material, and eliminate the need for reaming. This improves the hole wall quality and hole wall strengthening effect, thereby producing a better fatigue resistance effect. Attached Figure Description
[0026] Figure 1 This is a schematic diagram of the hole wall strengthening device in an embodiment of the present invention;
[0027] Figure 2 This is a cross-sectional view of the hole wall strengthening device in an embodiment of the present invention;
[0028] Figure 3 This is a schematic diagram of the spinning head in an embodiment of the present invention;
[0029] Figure 4 This is a cross-sectional view of the spinning head in an embodiment of the present invention;
[0030] Figure 5 This is a schematic diagram illustrating the fit between the spinning head and the bore wall in the first strengthening stage of an embodiment of the present invention.
[0031] Figure 6 This is a schematic diagram illustrating the fit between the spinning head and the hole wall during the second strengthening stage in an embodiment of the present invention.
[0032] Figure 7 This is a schematic diagram showing the fit between the spinning head and the hole wall after the reinforcement is completed in an embodiment of the present invention.
[0033] In the picture:
[0034] 100. Workpiece; 110. Reinforced area;
[0035] 1. Outer shell; 2. Base; 3. Drive assembly; 31. Body; 32. Output end; 4. Mold base; 5. Positioning seat; 6. Positioning pin; 7. Spinning head; 71. Extrusion section; 72. Spinning section; 721. First spinning section; 722. Second spinning section. Detailed Implementation
[0036] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. 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.
[0037] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The terms "first position" and "second position" refer to two different positions. Furthermore, "above," "on top of," and "over" the first feature in relation to the second feature includes the first feature directly above and diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "under," and "below" the first feature in relation to the second feature includes the first feature directly below and diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.
[0038] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.
[0039] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.
[0040] like Figures 1-7As shown, this embodiment of the invention provides a hole wall strengthening device for strengthening the hole wall of a hole to be strengthened on a workpiece 100. The workpiece 100 includes, but is not limited to, various structural components on aircraft, and the hole to be strengthened is a connection hole for mating with fasteners. The hole wall strengthening device includes a positioning assembly, a spinning head 7, and a driving assembly 3. The positioning assembly has a guide hole and is used to connect to the workpiece 100, aligning the axis of the guide hole with the axis of the hole to be strengthened on the workpiece 100. The spinning head 7 is movably disposed within the guide hole, its axis aligning with the axis of the guide hole and capable of rotating around the axis of the guide hole. The spinning head 7 has a protruding spinning structure extending axially along the spinning head 7, which is used to compress the hole wall of the hole to be strengthened. Aligning the axis of the spinning head 7 with the axis of the guide hole avoids impact on the hole wall during the rotation of the spinning head 7, resulting in a more uniform distribution of residual compressive stress in the strengthened area 110 of the hole wall after strengthening. The driving assembly 3 is mounted on the positioning assembly and can drive the spinning head 7 to rotate around the axis of the guide hole. By protruding a spinning structure on the spinning head 7 to compress the hole wall to be strengthened, a certain degree of plastic deformation is generated at the contact point between the hole wall and the spinning structure, forming a strengthened region 110. The strengthened region 110 has a high residual compressive stress, thereby improving the fatigue resistance of the hole wall in the strengthened region 110. The spinning head 7 only compresses the hole wall with the spinning structure, thus reducing the interaction force between the spinning head 7 and the hole wall, eliminating the need for a slotted bushing. By driving the spinning head 7 to rotate through the drive assembly 3, the strengthened region 110 can be continuously extended circumferentially along the hole wall, ultimately achieving surface strengthening of the entire hole wall. This effectively controls the cumulative plastic deformation of the hole wall, prevents damage to the hole wall material, and eliminates the need for reaming, thereby improving the hole wall quality and strengthening effect, and ultimately producing a better fatigue resistance.
[0041] Specifically, such as Figures 1-3As shown, the spinning head 7 includes an insertion section 71 and a spinning section 72. The insertion section 71 guides the spinning section 72 into the hole to be strengthened, and the spinning structure is disposed on the spinning section 72. The insertion section 71 facilitates the spinning head 7's passage through the hole to be strengthened. The insertion section 71 includes a small end and a large end, with the large end connected to the spinning section 72. During the strengthening operation, the small end of the insertion section 71 first enters the hole to be strengthened, followed by the large end of the insertion section 71 and the spinning section 72. The spinning structure compresses the corresponding hole wall until the spinning section 72 partially passes through the hole, ensuring the spinning structure fully adheres to and compresses the hole wall along its axial direction. The process of the spinning head 7 entering and passing through the hole to be strengthened can be driven by an additional driving component or by a driving assembly 3. In this embodiment, the driving assembly 3 can also drive the spinning head 7 to move axially along a guide hole, allowing the spinning head 7 to pass through or be pulled out of the hole to be strengthened. The drive assembly 3 can be a stroke-rotation composite hydraulic cylinder, capable of simultaneously outputting linear reciprocating motion and rotary motion, thereby driving the spinning head 7 through the hole to be strengthened and rotating it. The specific structure of the stroke-rotation composite hydraulic cylinder is prior art and will not be described here. The drive assembly 3 can also be a combination of two drive devices. For example, the first drive device drives the spinning head 7 to rotate, and the output shaft of the second drive device is connected to the body of the first drive device, enabling the first drive device to move axially along the guide hole, thus driving the spinning head 7 to move axially along the guide hole. In this embodiment, the drive assembly 3 is preferably a single stroke-rotation composite hydraulic cylinder to reduce the volume of the hole wall strengthening device.
[0042] Furthermore, such as Figures 1-2As shown, the positioning assembly includes a mold base 4 and a positioning seat 5. The mold base 4 is fixedly connected to the workpiece 100. The positioning seat 5 and the mold base 4 are positioned and engaged by several positioning pins 6. The positioning seat 5 has a guide hole. The positioning seat 5 and the mold base 4 are positioned and engaged by multiple positioning pins 6 to ensure the positioning accuracy between the positioning seat 5 and the mold base 4 through over-positioning. The hole wall strengthening device also includes a base 2 and a housing 1. The base 2 is fixedly connected to the positioning seat 5, and the housing 1 is fixedly connected to the base 2. The base 2 and the housing 1 together form a receiving space for accommodating the drive assembly 3. The drive assembly 3 is installed in the receiving space. The drive assembly 3 includes a body 31 and an output end 32. The body 31 is fixedly connected to the inner wall of the housing 1, and the output end 32 is fixedly connected to the spinning head 7. The spinning head 7 passes through the base 2 and then through the guide hole on the positioning seat 5. When installing the positioning component onto the workpiece 100, the relative positional relationship between the guide hole after positioning and mating of the mold base 4 and the mounting hole of the mold base 4 is first determined by the relative positional relationship between the guide hole and the mounting hole of the mold base 4. Combined with the hole position of the hole to be strengthened on the workpiece 100, a threaded hole corresponding to the mounting hole of the mold base 4 is opened on the workpiece 100. The mold base 4 is then fixedly connected to the workpiece 100 by fasteners, so that the guide hole on the positioning base 5 is coaxial with the hole position of the hole to be strengthened on the workpiece 100, thereby achieving coaxiality between the spinning head 7 and the hole to be strengthened.
[0043] Specifically, such as Figures 3-4 and refer to Figures 5-6As shown, the spinning structure includes a first spinning portion 721 and a second spinning portion 722, with a smooth transition between their outer surfaces. In this embodiment, the outer surface of the first spinning portion 721 is preferably a cylindrical surface, and the outer surface of the second spinning portion 722 is preferably a cylindrical surface, with the two surfaces tangentially arranged. In other embodiments, the outer surfaces of the first spinning portion 721 and the second spinning portion 722 can also be set as other types of curved surfaces, including but not limited to parabolic surfaces and toothed surfaces, and the smooth transition between the outer surfaces of the first spinning portion 721 and the second spinning portion 722 can be achieved by the tangency of the curved surfaces or the continuous and uniform change of curvature at the junction of the two curved surfaces. When the spinning structure enters the hole to be strengthened, the spinning structure compresses the hole wall, at which point the transition position of the outer surfaces of the first spinning portion 721 and the second spinning portion 722 contacts the hole wall. When the spinning head 7 rotates clockwise, the outer surface of the first spinning part 721 faces the hole wall to be strengthened along the rotation direction of the spinning head 7, thus the first spinning part 721 is used to compress the hole wall to be strengthened. When the spinning head 7 rotates counterclockwise, the outer surface of the second spinning part 722 faces the hole wall to be strengthened along the rotation direction of the spinning head 7, thus the second spinning part 722 is used to compress the hole wall to be strengthened. By setting the first spinning part 721 and the second spinning part 722, the spinning head 7 can effectively compress the hole wall in both clockwise and counterclockwise directions, and in different directions. Thus, by changing the rotation direction of the spinning head 7 during the strengthening process, pressure is applied to the hole wall material in different directions, effectively disrupting the original grain structure of the material, promoting grain refinement and dislocation reorganization, thereby forming a more robust strengthened region 110. At the same time, it helps to push plastic deformation and residual compressive stress radially deeper into the material, forming a stress gradient that smoothly decays from the surface to the interior of the hole wall, further improving the fatigue resistance of the strengthened region 110.
[0044] Optionally, multiple spinning structures are configured, spaced apart circumferentially along the spinning head 7. During the strengthening process, these multiple spinning structures simultaneously compress and strengthen different areas of the hole wall, thereby improving work efficiency. The number of spinning structures is even, such as 2, 4, 6, or 8, and they are evenly distributed circumferentially along the spinning head 7, ensuring that the multiple spinning structures are centrally symmetrical about the axis of the spinning head 7. During operation, the interaction forces between two spinning structures radially opposite each other along the spinning head 7 and the hole wall are equal in magnitude and opposite in direction, thus canceling out the torques acting on the spinning head 7, preventing bending or torsional deformation of the spinning head 7, and further ensuring a uniform distribution of residual compressive stress in the strengthened area 110.
[0045] Furthermore, such as Figures 3-4As shown, the curvature of the first spinning section 721 is greater than that of the second spinning section 722. In the initial stage of spinning reinforcement of the hole wall, the spinning head 7 rotates forward to make the first spinning section 721 with greater curvature undergo plastic deformation more quickly; then the spinning head 7 reverses to re-extract the hole wall area that has already undergone plastic deformation, thereby uniformly distributing the stress in the area and improving the surface quality of the hole wall.
[0046] This invention provides a method for strengthening pore walls, implemented using a pore wall strengthening device. The pore wall strengthening method includes:
[0047] Position the positioning component on the workpiece 100 so that the axis of the guide hole coincides with the axis of the hole to be strengthened.
[0048] The drive component 3 drives the spinning head 7 to continuously squeeze part of the hole wall to be strengthened.
[0049] By using the hole wall strengthening device in this embodiment and the hole wall strengthening method in this embodiment to strengthen the hole wall, the extrusion resistance of the spinning head 7 is smaller, the rotation resistance of the spinning head 7 during the strengthening process is smaller, the plastic deformation of the material at the hole wall is controllable, effectively avoiding damage to the hole wall material, and no reaming is required after strengthening, so the strengthened area 110 will not be damaged. The hole wall quality and hole wall strengthening effect are further improved, resulting in a better fatigue resistance effect.
[0050] Specifically, such as Figures 5-7 As shown, the drive assembly 3 drives the spinning head 7 to rotate around the axis of the guide hole and continuously press the hole wall of the hole to be strengthened, including:
[0051] The drive component 3 drives the spinning head 7 to rotate clockwise around the axis of the guide hole by a first preset angle;
[0052] The drive component 3 drives the spinning head 7 to rotate in reverse around the axis of the guide hole by a second preset angle;
[0053] The drive component 3 drives the spinning head 7 to rotate clockwise around the axis of the guide hole by a third preset angle;
[0054] The sum of the first preset angle and the third preset angle equals the second preset angle.
[0055] After the spinning head 7 passes through the hole to be strengthened, both the spinning head 7 and the hole are in their initial state. In this initial state, the drive assembly 3 drives the spinning head 7 to rotate clockwise around the axis of the guide hole by a first preset angle, such as... Figure 5 As shown, this process is the first reinforcement stage. Please refer to... Figures 5-6 As shown, during the first strengthening stage, the first spinning part 721 of the spinning head 7 sweeps along the circumferential direction across the hole wall in an arc-shaped trajectory with a first preset angle. Please refer to... Figure 5As shown in trajectory S1, the corresponding hole wall is plastically deformed by compression. During this process, due to the large curvature of the first spinning part 721, the hole wall is more easily plastically deformed, which helps to reduce the resistance in the subsequent strengthening stage. After the first strengthening stage, the obtained strengthened region 110 is as follows: Figure 6 As shown. Please continue to refer to. Figure 6 As shown, after the first strengthening stage, the drive assembly 3 drives the spinning head 7 to reverse the axis of the guide hole by a second preset angle. This process is the second strengthening stage. During the second strengthening stage, the trajectory swept by the second spinning part 722 first passes through the strengthened area 110 of the first strengthening stage, and then passes through the unstrengthened area of the first strengthening stage. It should be noted that the movement of the second spinning part 722 in the second strengthening stage is continuous. In this embodiment, for ease of description, it is distinguished. During the process of the trajectory swept by the second spinning part 722 passing through the strengthened area 110 of the first strengthening stage, the second spinning part 722 performs a secondary compression on the strengthened area 110, and the compression direction is opposite to the compression direction of the first spinning part 721, thereby effectively disrupting the original grain structure of the material, promoting grain refinement and dislocation reorganization, and thus forming a more robust strengthened area 110. After the second spinning part 722 reverses to the edge of the strengthened area 110 of the first strengthening stage, the trajectory swept by the second spinning part 722 passes through the unstrengthened area of the first strengthening stage and compresses it. Please refer to... Figure 6 The trajectory S2 is shown in the diagram. During the second strengthening stage, the strengthened area 110 of the first strengthening stage is successively squeezed by the first spinning part 721 and the second spinning part 722, and the second spinning part 722 further strengthens the area that was not strengthened in the first strengthening stage. After the second strengthening stage is completed, the drive assembly 3 drives the spinning head 7 to rotate clockwise around the axis of the guide hole by a third preset angle; this process is the third strengthening stage. During the third strengthening stage, the trajectory swept by the first spinning part 721 strengthens the area that has only undergone the strengthening in the second strengthening stage. Please refer to... Figure 6The trajectory S3 is shown in the diagram. The first spinning section 721 performs a secondary extrusion on the area, and the extrusion direction is opposite to that of the second spinning section 722, which can also form a more resilient reinforced area 110. Furthermore, by combining the fact that the sum of the first and third preset angles equals the second preset angle, the inner wall area swept by the spinning structure is extruded twice, resulting in a better strengthening effect. The values of the first, second, and third preset angles depend on the number of spinning structures. If the number of spinning structures is n, then the second preset angle is 360° / n, and the sum of the first and third preset angles is 360° / n. Preferably, the first and third preset angles are equal, i.e., both are 180° / n. In this embodiment, there are four spinning structures, evenly distributed along the circumference of the spinning head 7. Correspondingly, the second preset angle is 90 degrees, and the first and second preset angles are equal and both are 45°.
[0056] For example, the thickness of the workpiece 100 ranges from 6 to 40 mm, such as 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, 15 mm, 16 mm, 17 mm, 18 mm, 19 mm, 20 mm, 21 mm, 22 mm, 23 mm, 24 mm, 25 mm, 26 mm, 27 mm, 28 mm, 29 mm, 30 mm, 31 mm, 32 mm, 33 mm, 34 mm, 35 mm, 36 mm, 37 mm, 38 mm, 39 mm, or 40 mm. The diameter of the hole to be reinforced ranges from 6.5 to 25.5 mm, for example, it can be 6.5 mm, 7 mm, 7.5 mm, 8 mm, 8.5 mm, 9 mm, 9.5 mm, 10 mm, 10.5 mm, 11 mm, 11.5 mm, 12 mm, 12.5 mm, 13 mm, 13.5 mm, 14 mm, 14.5 mm, 15 mm, 15.5 mm, 16 mm, 16.5 mm, 17 mm, 17.5 mm, 18 mm, 18.5 mm, 19 mm, 19.5 mm, 20 mm, 20.5 mm, 21 mm, 21.5 mm, 22 mm, 22.5 mm, 23 mm, 23.5 mm, 24 mm, 24.5 mm, 25 mm, or 25.5 mm. Taking workpiece 100 as an example of a 10mm thick 7050-T7451 aluminum alloy sheet with a 9.5mm diameter hole to be strengthened, the process of strengthening the hole wall of the hole to be strengthened on workpiece 100 using the hole wall strengthening device in this embodiment is described. First, select the appropriate specifications of the spinning head 7 and positioning assembly according to the sheet thickness, hole diameter, and expected strengthening area 110 depth; process holes and threads are machined on workpiece 100 according to the specifications of the die base 4, and the die base 4 is connected to workpiece 100 through the threaded hole, ensuring that the coaxiality deviation between the center hole of the die base 4 for the positioning seat 5 to pass through and the hole to be strengthened is ≤0.001d, where d is the diameter of the hole to be strengthened; then, the spinning head 7 is installed to the output end 32 of the stroke rotary composite hydraulic cylinder; then, the positioning seat 5 is positioned and engaged with the die base 4 through the positioning pin 6; then, the stroke end of the stroke rotary composite hydraulic cylinder is started, causing the extrusion section 71 to move towards the... The spin head 72 is inserted and passes through the hole to be strengthened until part of the spin section 72 also passes through the hole, aligning the middle of the spin section 72 with the hole wall. The stroke end of the stroke rotary hydraulic cylinder is then closed. The rotation end of the stroke rotary hydraulic cylinder is then started, causing the spin head 7 to rotate 90° clockwise, then 180° counterclockwise, and finally 90° clockwise to complete the surface strengthening operation of the hole wall. The rotation end of the stroke rotary hydraulic cylinder is then closed. The stroke end of the stroke rotary hydraulic cylinder is then started, causing the spin head 7 to disengage from the strengthened hole. Finally, the hole wall strengthening device is removed from the workpiece 100, and the process holes on the workpiece 100 are sealed.After actual verification and comparison, the fatigue DFR value of the unstrengthened hole wall on workpiece 100 is 116MPa, the fatigue DFR value of the hole wall after being strengthened by push-out cold expansion extrusion in related technologies is 129MPa, and the fatigue DFR value of the hole wall after being strengthened by the hole wall strengthening device and hole wall strengthening method in this embodiment is 138MPa, and the strengthening effect is significantly improved.
[0057] The above description is merely a preferred embodiment of the present invention and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of disclosure in this invention is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the above-disclosed concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this invention.
[0058] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.
Claims
1. A hole wall strengthening device, characterized in that, include: A positioning component is provided with a guide hole. The positioning component is used to connect with the workpiece (100) and make the axis of the guide hole coincide with the axis of the hole to be strengthened on the workpiece (100). A spinning head (7) has its axis aligned with the axis of the guide hole and can rotate around the axis of the guide hole. The spinning head (7) has a spinning structure protruding from it. The spinning structure extends along the axial direction of the spinning head (7). The spinning structure is used to press the hole wall of the hole to be strengthened. The spinning structure includes a first spinning part (721) and a second spinning part (722). The outer surfaces of the first spinning part (721) and the second spinning part (722) are smoothly transitioned. A drive assembly (3) is mounted on the positioning assembly, and the drive assembly (3) is capable of driving the spinning head (7) to rotate about the axis of the guide hole.
2. The hole wall strengthening device according to claim 1, characterized in that, The spinning head (7) includes an extrusion section (71) and a spinning section (72). The extrusion section (71) can guide the spinning section (72) into the hole to be strengthened. The spinning structure is disposed on the spinning section (72).
3. The hole wall strengthening device according to claim 2, characterized in that, The drive assembly (3) can also drive the spinning head (7) to move axially along the guide hole.
4. The hole wall strengthening device according to claim 1, characterized in that, When the spinning head (7) rotates forward, the first spinning part (721) is used to press the hole wall of the hole to be strengthened; when the spinning head (7) rotates in reverse, the second spinning part (722) is used to press the hole wall of the hole to be strengthened.
5. The hole wall strengthening device according to claim 1, characterized in that, The spinning structure is configured as a plurality of structures, which are spaced apart circumferentially along the spinning head (7).
6. The hole wall strengthening device according to any one of claims 1-5, characterized in that, The positioning component includes a mold base (4) and a positioning seat (5). The mold base (4) is used to fix and connect with the workpiece (100). The positioning seat (5) is positioned and cooperates with the mold base (4). The positioning seat (5) has the guide hole.
7. The hole wall strengthening device according to claim 6, characterized in that, It also includes a base (2) and a housing (1), the base (2) being fixedly connected to the positioning seat (5), the housing (1) being fixedly connected to the base (2), the base (2) and the housing (1) together forming a receiving space for accommodating the drive component (3), and the drive component (3) being installed in the receiving space.
8. A method for strengthening the pore wall, characterized in that, The hole wall strengthening method, implemented by any one of claims 1-7, comprises: Position the positioning component on the workpiece (100) so that the axis of the guide hole coincides with the axis of the hole to be strengthened. The drive assembly (3) drives the spinning head (7) to rotate around the axis of the guide hole and squeeze the hole wall of the hole to be strengthened.
9. The hole wall strengthening method according to claim 8, characterized in that, The drive assembly (3) drives the spinning head (7) to rotate around the guide hole axis and press the hole wall of the hole to be strengthened, including: The drive assembly (3) drives the spinning head (7) to rotate clockwise around the axis of the guide hole by a first preset angle; The drive assembly (3) drives the spinning head (7) to reverse the axis of the guide hole by a second preset angle; The drive assembly (3) drives the spinning head (7) to rotate clockwise around the axis of the guide hole by a third preset angle; The sum of the first preset angle and the third preset angle equals the second preset angle.