Spinning folding control method and system for obliquely-arranged crossed rib barrel

Abstract

The invention provides a spinning folding control method and system for an inclined crossed rib barrel. The method comprises the steps that S1, a process supplement area is additionally arranged below a rib body; s2, using the established finite element simulation model to evaluate the cross rib cylinder after the process supplement area is added; and S3, according to the evaluation result, a preset spinning process scheme is used for completing the workpiece. According to the spinning folding control method for the obliquely-arranged crossed rib barrel, rib folding and influence caused by rib folding can be effectively avoided, the quality of produced parts is greatly improved, operation is easy, implementation is convenient, and good practicability is achieved; and limitation is given to newly-added process supplementation, the influence on the original machining efficiency is extremely small, and the spinning production benefit of the obliquely-arranged cross rib barrel is integrally improved.

Description

Technical Field

[0001] The present invention relates to the technical field of spinning, and particularly to a method and system for controlling the spinning and folding of a thin-walled cylinder with obliquely arranged cross ribs. Background Art

[0002] The thin-walled cylinder with obliquely arranged cross ribs is a component of a rocket fuel tank. At present, the processing route of mechanical milling - bending forming - welding assembly is often used in engineering. However, this process has disadvantages such as long processing cycle, difficult welding and assembly, and low material utilization rate. Flow spinning is a local plastic forming technology and has potential application prospects in the integrated forming of thin-walled cylinders with cross internal ribs. However, due to the complex structure and uneven material flow, folding defects are likely to occur at the cross position of the internal ribs, as Figure 1 shown. This kind of defect destroys the continuity of the metal, reduces the bearing capacity of the part. At the same time, it is also a notch on the workpiece, causing stress concentration during use and becoming a fatigue source, which may lead to fatigue fracture of the component here.

[0003] Due to the requirement of a full and plump rib body, it is necessary to ensure sufficient downward pressure or thinning rate. A larger thinning rate leads to more intense material flow and exacerbates folding. Other common process parameter adjustments, such as feed rate, spinning wheel attack angle, spinning wheel fillet, etc., have no effect on this defect. Therefore, it is urgent to develop a control method to improve the quality of the spinning forming of thin-walled cylinders with obliquely arranged cross ribs. Summary of the Invention

[0004] Aiming at the defects in the prior art, the purpose of the present invention is to provide a method and system for controlling the spinning and folding of a thin-walled cylinder with obliquely arranged cross ribs.

[0005] According to a method for controlling the spinning and folding of a thin-walled cylinder with obliquely arranged cross ribs provided by the present invention, it includes:

[0006] Step S1: Add a process supplementary area under the rib body;

[0007] Step S2: Use the established finite element simulation model to evaluate the cross-rib cylinder after adding the process supplementary area;

[0008] Step S3: According to the evaluation result, complete the workpiece using a predetermined spinning process plan.

[0009] Preferably, it further includes:

[0010] Step S4: If folding occurs in the process supplementary area of the workpiece or the weight of the workpiece exceeds the design index value, machine it to remove.

[0011] Preferably, the step S1 includes:

[0012] Based on the relative motion of the obliquely arranged cross ribs and the predetermined roller, a process supplementary area is added under the rib body; the process supplementary area includes a triangular area, and the bottom boundary is horizontally designed.

[0013] Preferably, the process supplementary area is only added at one corner of the cross position, axially located in the opposite direction of the roller movement, and circumferentially located on the side of the first filling.

[0014] Preferably, the length of the process supplementary area is more than 0.5 times the maximum value of the circumferential width and the axial width of the rib cross area.

[0015] Preferably, according to the circumferential width and the axial width of the cross area, the length of the triangular area is set as follows:

[0016] If the circumferential width Wc of the cross area is equal to the axial width Wa, the length L of the triangular area = 1 * Wc;

[0017] If the circumferential width Wc of the cross area is greater than the axial width Wa, the length L of the triangular area = 1 * Wc;

[0018] If the circumferential width Wc of the cross area is less than the axial width Wa, the length L of the triangular area = 1 * Wa.

[0019] Preferably, the weight of the cross rib cylinder after adding the process supplementary area does not exceed 3% of the weight of the original cross rib cylinder.

[0020] Preferably, the finite element model is locally divided at the rib position so that the rib fillet contains more than 6 meshes; the stress of the cross rib cylinder after adding the process supplementary area under the required load condition is less than the stress of the original cross rib cylinder under the same load condition.

[0021] A spinning and folding control system for an obliquely arranged cross rib cylinder provided by the present invention includes:

[0022] Module M1: Add a process supplementary area under the rib body;

[0023] Module M2: Evaluate the cross rib cylinder after adding the process supplementary area using the established finite element simulation model;

[0024] Module M3: Complete the workpiece according to the evaluation result using the predetermined spinning process plan.

[0025] Preferably, it further includes:

[0026] Module M4: If folding occurs in the process supplementary area of the workpiece or the weight of the workpiece exceeds the design index value, machine it to remove.

[0027] Preferably, the module M1 includes:

[0028] Based on the relative motion between the design of the inclined cross ribs and the predetermined roller, a process supplementary area is added under the rib body; the process supplementary area includes a triangular area, and the bottom boundary is horizontally designed.

[0029] Preferably, the process supplementary area is only added at one corner of the crossing position, axially located in the opposite direction of the roller movement, and circumferentially located on the side of the first filling.

[0030] Preferably, the length of the process supplementary area is more than 0.5 times the maximum value of the circumferential width and the axial width of the rib crossing area.

[0031] Preferably, according to the circumferential width and the axial width of the crossing area, the length of the triangular area is set as follows:

[0032] When the circumferential width Wc of the crossing area is equal to the axial width Wa, the length L of the triangular area = 1 * Wc;

[0033] When the circumferential width Wc of the crossing area is greater than the axial width Wa, the length L of the triangular area = 1 * Wc;

[0034] When the circumferential width Wc of the crossing area is less than the axial width Wa, the length L of the triangular area = 1 * Wa.

[0035] Preferably, the weight of the cross-rib cylinder after adding the process supplementary area does not exceed 3% of the weight of the original cross-rib cylinder.

[0036] Preferably, the finite element model is locally divided at the rib position so that the rib fillet contains more than 6 meshes; the stress of the cross-rib cylinder after adding the process supplementary area under the required load condition is less than the stress of the original cross-rib cylinder under the same load condition.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] 1. The method for controlling the spinning and folding of the inclined cross-rib cylinder provided by the present invention can effectively avoid the generation and influence of rib folding, greatly improve the quality of the produced parts, and is simple to operate and easy to implement, with good practicability.

[0039] 2. The present invention places restrictions on the newly added process supplement, has minimal impact on the original processing efficiency, and overall improves the spinning production efficiency of the inclined cross-rib cylinder.

[0040] Other beneficial effects of the present invention will be elaborated in the specific implementation manner through the introduction of specific technical features and technical solutions. Those skilled in the art should be able to understand the beneficial technical effects brought by the technical features and technical solutions through these introductions. Description of the Drawings

[0041] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non - limiting embodiments read in conjunction with the accompanying drawings:

[0042] Figure 1 It is a diagram of the spinning and folding defects of the inclined cross - rib cylinder in the present invention.

[0043] Figure 2 It is a schematic diagram of the intersection of the inclined ribs in the present invention.

[0044] Figure 3 It is a schematic diagram of the process supplement addition at the intersection of the inclined ribs in the present invention.

[0045] Figure 4 It is a stress distribution diagram of a rib unit with process supplement added in the present invention.

[0046] Figure 5 It is a diagram of the part experiment results with process supplement added in the present invention.

[0047] Figure 6 It is a flowchart of the method of the present invention. Detailed Embodiments

[0048] The present invention will be described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several changes and improvements can still be made. These all fall within the protection scope of the present invention.

[0049] During the process of spinning the inclined cross - rib cylinder, the material will have intense circumferential and axial flow. The reason for the folding at the intersection of the ribs is that excessive axial flow causes poor die - fitting of the material with the upstream of the rib groove, and excessive circumferential flow causes the subsequent supplementary material in the die - fitting - poor area to be not the radial inflow of the wall plate, but to be circumferentially extruded in the rib groove, forming folding.

[0050] By adding process supplement, increasing the size of the rib groove at the easily folded position, and increasing the filling requirement of the material at this position, excessive axial flow of the material and circumferential flow in the rib groove can be controlled, and folding can be avoided to a certain extent. If there is still folding in the process supplement area or the weight of the workpiece exceeds the design index value, it can also be selected to remove the process supplement by a small amount of machining without affecting the original structure.

[0051] A method for controlling the spinning and folding of an inclined cross - rib cylinder includes:

[0052] Step S1: Design process supplement at the intersection of the ribs;

[0053] The process supplement only adds one corner at the intersection position, axially located in the opposite direction of the roller movement, and circumferentially located on the side that is filled first. The length of the process supplement is more than 0.5 times the maximum value of the circumferential width and axial width of the rib intersection area. The weight of the cylinder after adding the process supplement should not exceed 3% of the weight of the original cylinder.

[0054] Step S2: Establish a finite element simulation model to evaluate the deformation strength of the cross-rib cylinder after adding the process supplement;

[0055] Specifically, select a unit containing the rib intersection and import it into the finite element model.

[0056] Establish a material model for the spun cylinder, which includes density, yield strength, elastic modulus, and Poisson's ratio.

[0057] Establish a static analysis step with a process time of 1 s.

[0058] Apply axial constraints at the bottom of the unit, circumferential constraints on both sides, and working condition loads at the top.

[0059] The finite element model needs to be locally divided at the rib position. Among them, there should be at least 10 meshes at the top of the rib, more than 6 meshes at the rib fillet, and the mesh size in the panel area should be at least 1 mm.

[0060] Submit the model for calculation to obtain the deformation result.

[0061] The stress of the cylinder after adding the process supplement under the required load conditions should be less than the stress of the original cylinder under the same load conditions.

[0062] Step S3: Develop a spinning process plan.

[0063] A single roller causes eccentric loading on the mandrel, and the common spinning machines have at most 4 rollers. Therefore, the number of rollers is selected from 2 to 4.

[0064] Step S4: Determine whether the process supplement area needs to be removed by machining according to the machining result of the workpiece or the design index of the workpiece weight.

[0065] When folding occurs in the process supplement area, remove the process supplement by machining.

[0066] When folding does not occur in the process supplement area, but the weight of the cylinder exceeds the design index requirements, remove the process supplement area by machining according to the drawing dimensions.

[0067] The method for controlling the spinning folding of the obliquely arranged cross-rib cylinder provided by the present invention can effectively avoid the generation and influence of rib folding, greatly improve the quality of the produced parts, and is simple to operate and easy to implement, with good practicability.

[0068] The above is the basic embodiment of the present invention. The technical solution of the present invention will be further described below through a preferred embodiment.

[0069] Embodiment 1

[0070] Referring to Figure 6 as shown, a method for controlling the spinning and folding of an inclined cross-reinforced cylinder is as follows:

[0071] Step S1: Based on the relative motion of the inclined cross-reinforcement design and the predetermined spinning wheel, as Figure 2 shown, a process supplement is added below the rib body. The process supplement is a triangular area, and the bottom boundary of the triangular area is horizontally designed, as Figure 3 shown.

[0072] If the circumferential width Wc of the cross region is equal to the axial width Wa, the length L of the triangular region = 1 * Wc;

[0073] If the circumferential width Wc of the cross region is greater than the axial width Wa, the length L of the triangular region = 1 * Wc;

[0074] If the circumferential width Wc of the cross region is less than the axial width Wa, the length L of the triangular region = 1 * Wa.

[0075] In this embodiment, the dimensions of the inclined cross-reinforced cylinder are: outer diameter 400 mm, wall thickness 6 mm, and cylinder length 400 mm. The dimensions of the rib body are: rib height 4 mm, rib width 4 mm, and draft angle 10°. The weight increases by 0.8% after adding the process supplement.

[0076] Step S2: Establish a finite element simulation model of a rib body unit, apply working conditions loads, and compare the changes in stress levels, as Figure 4 shown. Compared with the original cylinder, the stress of the cylinder after adding the process supplement is reduced.

[0077] Step S3: Adopt a 3-spinning-wheel spinning process, and the movement trajectory of the spinning wheel is consistent with the trajectory shown in Figure 2 . The dimensions of the cylinder blank are: inner diameter 394 mm, wall thickness 12 mm, and the pressing-down amount is 5 mm. The feeding speed of the spinning wheel is 1 mm / r, and the rotational speed of the mandrel is 50 r / min.

[0078] Step S4: The result of the workpiece is as Figure 5 shown, and there is no folding problem in the process supplement. In this embodiment, the increased weight of the process supplement is relatively small, and the process supplement can improve the problem of stress concentration, so the process supplement is retained.

[0079] The results of the embodiment show that the design of adding a process supplement at the intersection of the ribs proposed by the present invention can effectively control the spinning and folding of the inclined cross-reinforced cylinder, which has important significance for the manufacturing and process design of the spinning technology in the inclined cross-reinforced cylinder.

[0080] The present invention sets limits on the newly added process supplement, has minimal impact on the original processing efficiency, and overall improves the spinning production efficiency of the inclined cross-rib cylinder.

[0081] The present invention also provides a spinning and folding control system for an inclined cross-rib cylinder. The spinning and folding control system for the inclined cross-rib cylinder can be implemented by executing the process steps of the spinning and folding control method for the inclined cross-rib cylinder. That is, those skilled in the art can understand the spinning and folding control method for the inclined cross-rib cylinder as a preferred implementation manner of the spinning and folding control system for the inclined cross-rib cylinder.

[0082] Specifically, a spinning and folding control system for an inclined cross-rib cylinder includes:

[0083] Module M1: Add a process supplement area below the rib.

[0084] Module M2: Use the established finite element simulation model to evaluate the cross-rib cylinder after adding the process supplement area.

[0085] Module M3: According to the evaluation results, complete the workpiece using a predetermined spinning process plan.

[0086] It further includes:

[0087] Module M4: If folding occurs in the process supplement area of the workpiece or the weight of the workpiece exceeds the design index value, perform machining to remove it.

[0088] The said Module M1 includes:

[0089] Based on the relative motion between the inclined cross-rib design and the predetermined spinning wheel, add a process supplement area below the rib; the process supplement area includes a triangular area, and the bottom boundary is horizontally designed.

[0090] The process supplement area is only added at one corner of the cross position, axially in the opposite direction of the spinning wheel movement, and circumferentially on the side of the first filling.

[0091] The length of the process supplement area is more than 0.5 times the maximum value of the circumferential width and axial width of the rib cross area.

[0092] According to the circumferential width and axial width of the cross area, set the length of the triangular area:

[0093] If the circumferential width Wc of the cross area is equal to the axial width Wa, the length L of the triangular area = 1 * Wc;

[0094] If the circumferential width Wc of the cross area is greater than the axial width Wa, the length L of the triangular area = 1 * Wc;

[0095] When the circumferential width Wc of the cross - over region is less than the axial width Wa, the length L of the triangular region is L = 1 * Wa.

[0096] The weight of the cross - ribbed cylinder with the added process supplementary region does not exceed 3% of the weight of the original cross - ribbed cylinder.

[0097] The finite - element model is locally divided at the rib position so that the rib fillet contains more than 6 meshes; the stress of the cross - ribbed cylinder with the added process supplementary region under the required load - bearing conditions is less than the stress of the original cross - ribbed cylinder under the same load - bearing conditions.

[0098] Those skilled in the art know that, in addition to implementing the system and its various devices, modules, and units provided by the present invention in the form of pure computer - readable program code, the method steps can be logically programmed to enable the system and its various devices, modules, and units provided by the present invention to be implemented in the form of logic gates, switches, application - specific integrated circuits, programmable logic controllers, and embedded microcontrollers, etc., to achieve the same functions. Therefore, the system and its various devices, modules, and units provided by the present invention can be regarded as a kind of hardware component, and the devices, modules, and units included therein for implementing various functions can also be regarded as the structure within the hardware component; the devices, modules, and units for implementing various functions can also be regarded as either software modules for implementing the method or the structure within the hardware component.

[0099] The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the above - mentioned specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Without conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. A method for controlling the spinning and folding of an inclined cross-rib cylinder, characterized in that: include: Step S1: adding a process supplement area below the rib body; Step S2: using the established finite element simulation model to evaluate the cross-ribbed cylinder after adding the process supplement area; Step S3: Based on the evaluation results, a predetermined spinning process scheme is used to complete the part.

2. The method for controlling the spinning and folding of an inclined cross-rib cylinder according to claim 1, characterized in that: Also includes: Step S4: If the workpiece process supplement area is folded or the workpiece weight exceeds the design index value, it is mechanically processed to remove it.

3. The method for controlling the spinning and folding of a cylinder with inclined cross ribs according to claim 1 is characterized in that: The step S1 comprises: Based on the relative movement of the inclined cross rib design and the predetermined rotating wheel, a process supplement area is added below the rib body; the process supplement area includes a triangular area, and the bottom boundary is designed to be horizontal.

4. The method for controlling the spinning and folding of a cylinder with inclined cross ribs according to claim 3 is characterized in that: The process supplement area is only added with a corner at the intersection position, which is located in the opposite direction of the rotation wheel movement in the axial direction and is located on the side of the first filling in the circumferential direction.

5. The method for controlling the spinning and folding of a cylinder with inclined cross ribs according to claim 3 is characterized in that: The length of the process supplement area is more than 0.5 times the maximum value of the circumferential width and the axial width of the rib crossing area.

6. The method for controlling the spinning and folding of a cylinder with inclined cross ribs according to claim 3 is characterized in that: The length of the triangular area is set according to the circumferential width and axial width of the intersection area: If the circumferential width Wc of the intersection area is equal to the axial width Wa, the length of the triangular area L = 1*Wc; If the circumferential width Wc of the intersection area is greater than the axial width Wa, the length of the triangular area L = 1*Wc; If the circumferential width Wc of the intersection region is smaller than the axial width Wa, the length L of the triangular region = 1*Wa.

7. The method for controlling the spinning and folding of an inclined cross-rib cylinder according to claim 1, characterized in that: The weight of the cross-ribbed cylinder after adding the process supplement area shall not exceed 3% of the original cross-ribbed cylinder weight.

8. The method for controlling the spinning and folding of a cylinder with inclined cross ribs according to claim 1, characterized in that: The finite element model is locally divided at the reinforcement position so that the fillet of the reinforcement contains more than 6 grids; the stress of the cross reinforcement cylinder after adding the process supplement area under the required load condition is less than the stress of the original cross reinforcement cylinder under the same load condition.

9. A control system for the spinning and folding of an inclined cross-rib cylinder, characterized in that: include: Module M1: Add a process supplement area under the ribs; Module M2: Use the established finite element simulation model to evaluate the cross-ribbed cylinder after adding the process supplement area; Module M3: Based on the evaluation results, the predetermined spinning process plan is used to complete the part.

10. The control system for the spinning and folding of the inclined cross-rib cylinder according to claim 9, characterized in that: Also includes: Module M4: If the part process supplement area is folded or the part weight exceeds the design index value, it will be mechanically processed to remove it.

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