Turning method for small space of lightweight cabin section

Abstract

The invention relates to a turning method for a small space of a lightweight cabin section, and belongs to the technical field of spacecraft cabin machining. A cabin section three-dimensional model is manufactured according to the size of the light-weight cabin section real object; extracting features of a semi-closed groove needing to be processed from the cabin section three-dimensional model, and obtaining size information of the semi-closed groove; according to the size information of the semi-closed groove, a set of special turning tool for the semi-closed groove is manufactured; according to the size information of the semi-closed groove and the set of special turning tool, total turning steps are planned, and turning parameters are matched; the machining of the semi-closed rotation characteristics of the light-weight cabin is completed by adopting the planned cutter, the total turning steps and the turning parameters; the special hard alloy integral turning tool is designed, the machining route of the semi-closed groove characteristics is designed, turning parameters are matched, and the problem that narrow part characteristic machining cannot be achieved through a conventional method is solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of the processing of spacecraft cabin bodies, and relates to a turning method for a narrow space of a lightweight cabin section. Background Art

[0002] As a key component for carrying and connecting various functional components, the weight control of the spacecraft cabin body is a key issue, and the spacecraft cabin body is developing towards lightweight design. A certain lightweight thin-walled cabin section is a large lightweight thin-walled shell made of high specific strength aluminum alloy 5B70, and there is a strong demand for weight reduction. In order to fully reduce the weight on the premise of ensuring reliability, the sealed cabin body adopts an integral panel structure, in which the skin and the stiffeners are integrally processed from thick plates, the number of welds is reduced, and the continuous rib configuration is adopted to improve the sealing performance and reliability, and the structural quality is reduced. The cabin section structure is as Figure 1 shown.

[0003] The main technical difficulties in the development of a certain lightweight cabin section can be mainly attributed to the following two aspects:

[0004] 1) The groove for installing the hook on the internal pressure-bearing layer of the cabin body is a semi-closed structure, as Figure 2 shown. During the production process, turning processing is required. There is interference between the groove structure and the turning tool during the processing, and conventional turning tools cannot process the groove features of the product.

[0005] 2) It is difficult to suppress the vibration during turning.

[0006] After the product is integrally formed, the overall numerical control processing process route is adopted. Different from the traditional processing of the wall panel closely attached to the rigid fixture, the lightweight thin-walled cabin body is hollow and there is no rigid fixture for effective support. During the process of turning the groove features inside the cabin, due to the influence of resonance, turning force change, etc., it is very easy to cause machining vibration, and the machining risk is high.

[0007] Aiming at the difficulties that the cabin body is thin and prone to vibration during the manufacturing process of the lightweight cabin section, and there is machining interference in some narrow spaces of features, there is an urgent need for a turning tool and method for a narrow space of a lightweight cabin section to ensure the research and development progress and quality of the lightweight cabin body. Summary of the Invention

[0008] The technical problem solved by the present invention is: overcoming the deficiencies of the prior art, proposing a turning method for a narrow space of a lightweight cabin section, designing a special integral carbide turning tool, and designing a processing route for semi-closed groove features, and matching turning parameters to solve the problem that the conventional method cannot realize the processing of features in narrow parts.

[0009] The technical solution adopted by the present invention is:

[0010] A turning method for a narrow space of a lightweight cabin section, comprising:

[0011] Create a 3D model of the cabin section according to the physical size of the lightweight cabin section;

[0012] Extract the semi-closed groove features to be machined from the 3D model of the cabin section to obtain the size information of the semi-closed grooves;

[0013] Make a set of special turning tools for the semi-closed grooves according to the size information of the semi-closed grooves;

[0014] Plan the total turning steps and match the turning parameters according to the size information of the semi-closed grooves and this set of special turning tools;

[0015] Complete the machining of the semi-closed rotary features of the lightweight cabin body using the planned tools, total turning steps, and turning parameters.

[0016] In the above-mentioned turning method for the narrow space of the lightweight cabin section, the size information of the semi-closed grooves includes feature dimensions and geometric tolerances.

[0017] In the above-mentioned turning method for the narrow space of the lightweight cabin section, the special turning tools include 3 tools; one of them is a standard tool, and the other 2 tools are customized according to the size information of the semi-closed grooves.

[0018] In the above-mentioned turning method for the narrow space of the lightweight cabin section, the opening of the semi-closed groove is located at the side wall of the 3D model of the cabin section, and the bottom side wall of the semi-closed groove slopes upward; the cutting head of the standard tool is a horizontal structure; the cutting heads of the 2 customized tools are downward-sloping structures.

[0019] In the above-mentioned turning method for the narrow space of the lightweight cabin section, the 2 customized tools are both made of cemented carbide; the main cutting edge angle of the first customized tool is 15°, and the negative cutting edge angle is 45°; the main cutting edge angle of the second customized tool is 15°, and the negative cutting edge angle is 55°.

[0020] In the above-mentioned turning method for the narrow space of the lightweight cabin section, the planned total turning steps include 4 turning steps:

[0021] The first turning step:

[0022] Use the standard tool, install the standard tool parallel to the X-axis of the machine tool, and machine the part of the semi-closed groove opening parallel to the X-axis of the machine tool;

[0023] The second turning step:

[0024] Use the standard tool, install the tool body of the standard tool perpendicular to the side wall of the semi-closed groove, that is, rotate 5.3° during installation; use the contour copying turning path for turning;

[0025] The third turning step:

[0026] Select the first customized tool with a main cutting edge angle of 15° and a negative cutting edge angle of 45°; the first customized tool is installed parallel to the X-axis of the machine tool, and the bottom of the semi-closed groove is finish-machined with the tool path reciprocating.

[0027] The fourth turning step:

[0028] Select the second customized tool with a main cutting edge angle of 15° and a negative cutting edge angle of 55°; finish-machine the bottom of the semi-closed groove with the tool path reciprocating.

[0029] In the above-mentioned turning method for a narrow space of a lightweight cabin section, the turning parameters corresponding to the first turning step are:

[0030] The width of the standard tool is 3 mm; the turning step is 2.5 mm, the rotational speed S is 8 - 10 r / min, the feed rate F is 0.08 - 0.1 mm / min; the allowance left on the side wall is 0.1 mm - 0.5 mm.

[0031] In the above-mentioned turning method for a narrow space of a lightweight cabin section, the turning parameters corresponding to the second turning step are:

[0032] The rotational speed S is 8 - 10 r / min, the feed rate F is 0.08 - 0.1 mm / min, and the side wall of the semi-closed groove is turned to the current unprocessed position.

[0033] In the above-mentioned turning method for a narrow space of a lightweight cabin section, the turning parameters corresponding to the third turning step are:

[0034] The step is 0.1 mm, the rotational speed S is 8 - 10 r / min, the feed rate F is 0.08 - 0.1 mm / min, and the side wall of the semi-closed groove is turned to the current unprocessed position.

[0035] In the above-mentioned turning method for a narrow space of a lightweight cabin section, the turning parameters corresponding to the fourth turning step are:

[0036] The step is 0.1 mm, the rotational speed S is 8 - 10 r / min, the feed rate F is 0.08 - 0.1 mm / min, and the side wall of the semi-closed groove is turned.

[0037] The beneficial effects of the present invention compared with the prior art are:

[0038] (1) By designing two special turning tools for semi-closed grooves, the present invention solves the problem that the characteristics of a narrow space in a lightweight cabin section cannot be machined. By optimizing the turning route and matching the turning parameters, the vibration during machining is suppressed, and the machining accuracy of the product is guaranteed.

[0039] (2) In view of the difficulties that the wall thickness of the lightweight cabin section is thin, prone to machining vibration, and there is machining interference in some narrow feature spaces, the present invention designs a set of special solid carbide integral turning tools, designs a machining route for semi-closed groove features, and matches the turning parameters to solve the problem that the machining of features in narrow parts cannot be achieved by conventional methods;

[0040] (3) A set of special solid carbide integral turning tools of the present invention includes 1 standard tool and 2 customized tools, and the dimensional parameters of the 2 customized tools are respectively designed. The main cutting edge angle of the first customized tool is 15°, and the negative cutting edge angle is 45°; the main cutting edge angle of the second customized tool is 15°, and the negative cutting edge angle is 55°, which are respectively used for different turning steps to ensure the final forming accuracy. Description of the Drawings

[0041] Figure 1 is the turning flow chart of the narrow space of the lightweight cabin section of the present invention;

[0042] Figure 2 is the schematic diagram of the semi-closed groove of the present invention;

[0043] Figure 3 is a set of special turning tools for semi-closed grooves of the present invention;

[0044] Figure 4 is the schematic diagram of the first turning step of the present invention;

[0045] Figure 5 is the schematic diagram of the second turning step of the present invention;

[0046] Figure 6 is the schematic diagram of the third turning step of the present invention;

[0047] Figure 7 is the schematic diagram of the fourth turning step of the present invention. Detailed Embodiments

[0048] The present invention will be further described below in conjunction with embodiments.

[0049] The present invention provides a turning method for narrow spaces in lightweight cabin sections. In view of the difficulties that the wall thickness of the lightweight cabin section is thin, prone to machining vibration, and there is machining interference in some narrow feature spaces, the present invention designs a set of special solid carbide integral turning tools, designs a machining route for semi-closed groove features, and matches the turning parameters to solve the problem that the machining of features in narrow parts cannot be achieved by conventional methods.

[0050] The turning method for narrow spaces in lightweight cabin sections, as Figure 1 shown, specifically includes the following steps:

[0051] Make a three-dimensional model of the cabin section according to the physical dimensions of the lightweight cabin section.

[0052] Extract the semi-closed groove features to be machined from the three-dimensional model of the cabin section to obtain the size information of the semi-closed groove; the size information of the semi-closed groove includes feature dimensions and geometric tolerances.

[0053] According to the size information of the semi-closed groove, make a set of special turning tools for the semi-closed groove. The special turning tools include 3 tools; one of the tools is a standard tool, and the other 2 tools are customized according to the size information of the semi-closed groove. The opening of the semi-closed groove is located at the side wall of the three-dimensional model of the cabin section, and the bottom side wall of the semi-closed groove slopes upward, as Figure 2 shown.

[0054] The cutting head of the standard tool is a horizontal structure, as Figure 3 shown. The cutting heads of the 2 customized tools are downward-sloping structures. The specific design is as follows: both of the 2 customized tools select cemented carbide materials; the main cutting edge angle of the first customized tool is 15°, and the negative cutting edge angle is 45°; the main cutting edge angle of the second customized tool is 15°, and the negative cutting edge angle is 55°, as Figure 3 shown.

[0055] The considerations in the tool design of the present invention are as follows:

[0056] One of them selects a standard tool, and the other 2 need to be professionally designed according to the groove size. The tool design should follow the requirements in the following several directions.

[0057] 1) Select a tool body material with good economy according to the material of the product to be machined;

[0058] 2) Design the tool shape according to the shape and size of the turning surface, and require that the turning tool does not interfere with the product to be machined;

[0059] 3) The cutting edge is the most important turning part. Control the shape of the cutting edge and clarify the sizes of the main cutting edge angle and the negative cutting edge angle;

[0060] 4) Increase the tool strength as much as possible while ensuring the turning effect.

[0061] The 2 designed tools select cemented carbide material as the tool body design material according to the turning characteristics of aluminum alloy 5B70, and extract the product structure dimensions according to the shape of the turning surface

[0062] According to the size information of the semi-closed groove and this set of special turning tools, plan the total turning steps and match the turning parameters.

[0063] The planned total turning steps include 4 turning steps:

[0064] The first turning step:

[0065] As Figure 4As shown, a standard tool is used. The standard tool is installed parallel to the X-axis of the machine tool, and the semi-closed groove is machined with the opening in the part parallel to the X-axis of the machine tool.

[0066] The turning parameters corresponding to the first turning step are:

[0067] The width of the standard tool is 3 mm; the turning step is 2.5 mm, the rotational speed S is 8 - 10 r / min, the feed rate F is 0.08 - 0.1 mm / min; the allowance left on the side wall is 0.1 mm - 0.5 mm.

[0068] The second turning step:

[0069] As Figure 5 shown, a standard tool is used. The tool body of the standard tool is installed perpendicular to the side wall of the semi-closed groove, that is, rotated by 5.3° during installation; a contour profiling turning path is used for turning.

[0070] The turning parameters corresponding to the second turning step are:

[0071] The rotational speed S is 8 - 10 r / min, the feed rate F is 0.08 - 0.1 mm / min, and the side wall of the semi-closed groove is turned to the current unprocessed position.

[0072] The third turning step:

[0073] As Figure 6 shown, the first customized tool with a main cutting edge angle of 15° and a negative cutting edge angle of 45° is selected; the first customized tool is installed parallel to the X-axis of the machine tool to finish machining the bottom of the semi-closed groove, and the tool path reciprocates.

[0074] The turning parameters corresponding to the third turning step are:

[0075] The step is 0.1 mm, the rotational speed S is 8 - 10 r / min, the feed rate F is 0.08 - 0.1 mm / min, and the side wall of the semi-closed groove is turned to the current unprocessed position.

[0076] The fourth turning step:

[0077] As Figure 7 shown, the second customized tool with a main cutting edge angle of 15° and a negative cutting edge angle of 55° is selected; the bottom of the semi-closed groove is finish machined, and the tool path reciprocates.

[0078] The turning parameters corresponding to the fourth turning step are:

[0079] The step is 0.1 mm, the rotational speed S is 8 - 10 r / min, the feed rate F is 0.08 - 0.1 mm / min, and the side wall of the semi-closed groove is turned.

[0080] Use the planned cutting tools, total turning steps, and turning parameters to complete the machining of the semi-closed rotary features of the lightweight cabin body.

[0081] In view of the difficulties in the lightweight cabin section, such as thin wall thickness, easy generation of machining vibration, and machining interference in some narrow feature spaces, the present invention designs a set of special solid carbide turning tools, designs the machining route for semi-closed groove features, and matches the turning parameters to solve the problem that the features in narrow parts cannot be machined by conventional methods.

[0082] A set of special solid carbide turning tools of the present invention includes 1 standard tool and 2 customized tools, and the dimensional parameters of the 2 customized tools are designed respectively. The main cutting edge angle of the first customized tool is 15°, and the negative cutting edge angle is 45°; the main cutting edge angle of the second customized tool is 15°, and the negative cutting edge angle is 55°, which are used for different turning steps respectively to ensure the final forming accuracy.

[0083] Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solution of the present invention by using the methods and technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modification, equivalent change, and modification made to the above embodiments based on the technical essence of the present invention without departing from the technical solution of the present invention shall fall within the protection scope of the technical solution of the present invention.

Claims

1. A method for turning a light-weight cabin section in a narrow space, characterized in that: include: Make a three-dimensional model of the cabin according to the actual size of the lightweight cabin; Extract the semi-enclosed groove features that need to be processed from the cabin 3D model and obtain the semi-enclosed groove size information; According to the size information of the semi-closed groove, a set of special turning tools for the semi-closed groove is manufactured; According to the semi-enclosed groove size information and the set of special turning tools, plan the overall turning steps and match the turning parameters; The planned tools, overall turning steps and turning parameters are used to complete the processing of the semi-enclosed rotary features of the lightweight cabin.

2. The method for turning a lightweight cabin section in a narrow space according to claim 1, characterized in that: The semi-closed groove size information includes characteristic size and shape and position tolerance.

3. The method for turning a lightweight cabin section in a narrow space according to claim 2, characterized in that: The special turning tool includes three tools; one of which is a standard tool, and the other two tools are customized according to the size information of the semi-closed groove.

4. The method for turning a lightweight cabin section in a narrow space according to claim 3 is characterized in that: The opening of the semi-enclosed groove is located at the side wall of the three-dimensional model of the cabin section, and the bottom side wall of the semi-enclosed groove is inclined upward; the blade head of the standard tool is a horizontal structure; the blade heads of the two customized tools are a downward inclined structure.

5. The method for turning a lightweight cabin section in a narrow space according to claim 4, characterized in that: The two customized cutting tools are both made of cemented carbide; The main deflection angle of the first customized tool is 15°, and the negative deflection angle is 45°; the main deflection angle of the second customized tool is 15°, and the negative deflection angle is 55°.

6. The method for turning a lightweight cabin section in a narrow space according to claim 4, characterized in that: The total turning steps of the plan include 4 turning steps: 1st turning step: Use standard tools, which are installed parallel to the X-axis of the machine tool, and the opening of the semi-closed groove is parallel to the X-axis of the machine tool; 2nd turning step: A standard tool is used, and the tool body of the standard tool is installed vertically to the side wall of the semi-enclosed groove, that is, it is rotated 5.3° during installation; the contour profiling turning path is used for turning; 3rd turning step: The first customized tool with a main deflection angle of 15° and a negative deflection angle of 45° is selected; the first customized tool is installed parallel to the X-axis of the machine tool, and the bottom of the semi-closed groove is finely machined, and the tool trajectory reciprocates; 4th turning step: The second customized tool with a main deflection angle of 15° and a negative deflection angle of 55° was selected to finish the bottom of the semi-closed groove, with the tool trajectory moving back and forth.

7. The method for turning a lightweight cabin section in a narrow space according to claim 6, characterized in that: The turning parameters corresponding to the first turning step are: The width of the standard tool is 3mm; the turning step is 2.5mm, the rotation speed S is 8-10r / min, the feed speed F is 0.08-0.1mm / min; the side wall allowance is 0.1mm-0.5mm.

8. The method for turning a lightweight cabin section in a narrow space according to claim 6, characterized in that: The turning parameters corresponding to the second turning step are: The rotation speed S is 8-10r / min, the feed speed F is 0.08-0.1mm / min, and the side wall of the semi-closed groove is turned to a position that cannot be currently processed.

9. The method for turning a lightweight cabin section in a narrow space according to claim 6, characterized in that: The turning parameters corresponding to the third turning step are: The step distance is 0.1mm, the rotation speed S is 8-10r / min, the feed speed F is 0.08-0.1mm / min, and the side wall of the semi-closed groove is turned to a position that cannot be currently processed.

10. The method for turning a lightweight cabin section in a narrow space according to claim 6, characterized in that: The turning parameters corresponding to the fourth turning step are: The step distance is 0.1mm, the rotation speed S is 8-10r / min, the feed speed F is 0.08-0.1mm / min, and the side wall of the semi-closed groove is turned.

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