A method for processing aviation foam parts

Abstract

The invention discloses a method for machining aviation foam parts, which mainly includes the steps of: arranging; milling reference surface, anti-reverse angle and through hole; finishing arc surface; rough machining cavity surface; finishing cavity surface; benchwork blanking, etc. The invention solves the technical problems of easy brittle fracture of parts, low production efficiency and high production cost in the prior art through the aviation foam parts machining method.

Description

Technical Field

[0001] The invention relates to the field of aviation parts manufacturing, and in particular to a method for processing aviation foam parts. Background Art

[0002] PMI (polymethacrylimide) has the characteristics of good wave transmission, high specific strength, good heat resistance, good photosensitivity, and excellent electrical insulation. The strength of PMI foam exceeds that of honeycomb core materials and PET foam, and its specific strength (strength / density) is also much greater than other non-metallic structural materials. The manufactured parts have the characteristics of high unit strength, good rigidity, and light weight. It is widely used in the key auxiliary fields of shock absorption and sound absorption between the skin and trusses of aviation fuselages and wings.

[0003] In the prior art, a certain aircraft PMI foam part has a trapezoidal cross-section and a single-peak structure, with a length of 2020mm×width of 50mm×height of 45mm, and is in the form of a long and thin strip. The peak part is prone to brittle fracture at the peak due to the large amount of cutting removal and excessive milling vibration. Single-piece processing has low production efficiency. If vacuum suction cups are used for clamping and processing, after milling, the stress release will cause the part to warp and deform, and even cause the part to be scrapped. Summary of the invention

[0004] The purpose of the present invention is to provide a method for processing aviation foam parts to solve the technical problems of brittle fracture of parts, low production efficiency and high production cost in the prior art.

[0005] To achieve the above object, the present invention provides an aviation foam parts processing method, comprising the following steps:

[0006] S1. Arrangement: Arrange parts according to their maximum contour, arrange parts with the same height on the same foam blank, set the lower groove width to 15mm, and the process table thickness to 20mm;

[0007] S2, milling reference surface and anti-reverse angle, through hole: glue the blank to the machine tool workbench at intervals of 200mm around the blank, and the bonding range should not exceed 10×10mm; if the gap of the blank warping deformation is greater than 0.5mm, it is necessary to glue the process block on the side wall in the long direction of the blank; the top surface of the process block should be greater than 10mm away from the reference surface;

[0008] Drill 12 symmetrical through holes, of which 6 are reference holes and the other 6 are glue holes. The distance between the glue holes is 200mm. The process table and the workbench are bonded to ensure that the clamping force is dispersed to each supporting surface of the process table, reducing the risk of part cutting vibration and brittle fracture.

[0009] S3 finishing arc surface: The highest point of the arc surface of the part is 1mm away from the reference surface as the cutting point, and the area within 3mm of the maximum outer contour of the arc surface is reciprocated along the long direction of the surface to ensure that the reference surface provides stable support for the efficient rough machining cavity when using a smaller thickness blank;

[0010] After finishing the arc surface, use a tool slightly larger than the diameter of the glue hole to drill the glue hole. The drilling depth is to the bottom of the process table to remove the material in the adhesion area between the process table and the workbench to facilitate the disassembly of the parts.

[0011] S4. Rough machining of cavity surface: level the reference surface on the CNC machine tool, glue the process table and glue holes on the machine tool workbench at intervals of 200mm, and complete the workpiece clamping; use the solid hard end milling cutter specially used for the previous process for rough machining. The machining sequence is rough milling the right end bevel, rough milling the outer contour, and rough milling the process connection, leaving a uniform allowance of 2mm on one side.

[0012] S4, Finishing the cavity surface: Use small cutting amount and fast feed process to mill parts to ensure the outer dimensions;

[0013] After finishing the cavity surface, use a tool slightly larger than the diameter of the glue hole to drill the glue hole. The drilling depth is to the bottom of the process table to remove the material in the adhesion area between the process table and the workbench to facilitate the disassembly of the parts.

[0014] S5. Blanking by fitter: On the bench, the fitter wears white gloves and uses a utility knife to cut and connect the parts in an area 5mm away from the edge of the parts. After finishing, the parts are finished.

[0015] Further, in S2, in the process block for bonding the side wall in the long direction of the blank, the order of bonding the process blocks is:

[0016] S201, firstly place the bottom surface of the process block close to the workbench, and then move the process block horizontally to close to the side surface of the blank;

[0017] S202, first use glue to bond the process block to the workbench, and then use glue to bond the process block to the side of the blank.

[0018] Furthermore, the six reference holes in S2 are auxiliary reference holes for reviewing the position status of the parts, of which two reference holes are used for part straightening and alignment and for establishing the machining coordinate system, and the remaining four reference holes are used to detect power failure, gas failure, and tool milling failure of the machine tool;

[0019] The steps for using the 6 glue filling holes in S2 are as follows:

[0020] S211, use a solid hard end mill to drill a glue injection hole on the workbench surface, and use an air gun to clean the foam dust in the hole;

[0021] S212. Use a syringe to fill the glue holes with glue. The thickness of the glue filling is 5 mm. Visually check the fullness of the glue at the bottom of the glue filling holes.

[0022] S213, use an air gun to blow dry the glue, 1 minute for each hole;

[0023] S214, pressing the process table to check the adhesion between the workpiece and the workbench.

[0024] Furthermore, the milling reference surface, anti-backlash angle and through hole in S2 adopts a solid hard end mill with an installation diameter of 10mm, a blade length of 70mm and a tool bar clearance of 110mm; the milling reference surface, anti-backlash angle and through hole are divided into milling process and drilling process, and the milling process adopts a spindle speed of 12000r / min and a feed speed of 20000 mm / min; the cutting width is 10mm and the cutting depth is 70mm; the drilling process adopts a spindle speed of 3000r / min and a feed speed of 200mm / min.

[0025] Furthermore, in S3, a solid hard end mill with a diameter of 12 mm and a tip radius of R1 mm is used for finishing the milling of the arc surface; the milling process uses a spindle speed of 12000 r / min and a feed speed of 20000 mm / min; the cutting width is 1.2 mm and the cutting depth is 25 mm; the drilling process uses a machine tool spindle speed of 3000 r / min and a feed speed of 200 mm / min.

[0026] Furthermore, the specific steps of rough machining the cavity surface in S4 are:

[0027] S41, rough milling the right end inclined surface: use a special solid hard end mill to cut outside the processed area, reciprocate along the long direction of the inclined surface of the part to machine the bevel of the part;

[0028] S42, rough milling of the outer contour: using a dedicated solid hard end mill full-edge cutting process method, milling out 80 30×15mm process connection ends;

[0029] S43, Milling process connection: Use full-edge cutting process method to mill out 80 process connection ends to ensure the thickness of 5mm.

[0030] Furthermore, the finishing of the cavity surface in S5 uses a solid hard end mill with a diameter of 12 mm and a tip radius of 1 mm; the milling process uses a spindle speed of 12000 r / min; a feed speed of 20000 mm / min; a plane cutting width of 1.2 mm; a plane cutting depth of 5 mm; a chamfer cutting width of 11 mm; and a chamfer cutting depth of 0.25 mm.

[0031] Based on the above technical solution, the embodiments of the present invention can produce the following beneficial effects:

[0032] (1) The present invention provides a method for processing aviation foam parts, which uses glue bonding technology to disperse the pressing force, reduce cutting vibration, reduce operating difficulty and brittle fracture risk, and save costs; and uses sticky block processing technology to solve the impact of blank warping and deformation on parts;

[0033] (2) The present invention provides a method for processing aviation foam parts, which adopts multi-level rough processing technology to solve the brittle fracture at the peak; high-efficiency and high-speed processing technology to improve production efficiency; reduce the number of milling tools and reduce production costs; and bench cutting technology to solve the cutting force winding. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a processing flow chart of an embodiment of the present invention;

[0035] Figure 2 is a side view of a through hole structure according to an embodiment of the present invention;

[0036] Figure 3 is a structural diagram of a through hole structure according to an embodiment of the present invention;

[0037] Figure 4 Schematic diagram of a finely machined cambered surface according to an embodiment of the present invention;

[0038] Figure 5 is a side view of a finely machined cambered surface according to an embodiment of the present invention;

[0039] Figure 6 Schematic diagram of the precision-machined cavity surface according to an embodiment of the present invention;

[0040] Figure 7 It is a schematic diagram of a rough-machined inclined surface according to an embodiment of the present invention. DETAILED DESCRIPTION

[0041] In order to better understand the purpose, structure and function of the present invention, a method for processing aviation foam parts of the present invention is further described in detail below in conjunction with the accompanying drawings.

[0042] In the description of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0043] As shown in the figure, the present invention provides a method for processing aviation foam parts, comprising the following steps:

[0044] S1. Arrangement: Arrange parts according to their maximum contour, arrange parts with the same height on the same foam blank, set the lower groove width to 15mm, and the process table thickness to 20mm;

[0045] S2, milling reference surface and anti-reverse angle, through hole: glue the blank to the machine tool workbench at intervals of 200mm around the blank, and the bonding range should not exceed 10×10mm; if the gap of the blank warping deformation is greater than 0.5mm, it is necessary to glue the process block on the side wall in the long direction of the blank; the top surface of the process block should be greater than 10mm away from the reference surface;

[0046] like Figure 2-3 As shown, 12 mutually symmetrical through holes are drilled, of which 6 through holes are reference holes and the other 6 through holes are glue holes. The distance between the glue holes is 200mm. The process table and the workbench are bonded to ensure that the clamping force is dispersed to each supporting surface of the process table, reducing the risk of part cutting vibration and brittle fracture.

[0047] like Figure 4-5 As shown, S3 finishing arc surface: the highest point of the arc surface of the part is 1mm away from the reference surface as the cutting point, and the area within 3mm of the maximum outer contour of the arc surface is reciprocated along the long direction of the surface to ensure that the reference surface provides stable support for the efficient rough machining cavity when using a smaller thickness blank;

[0048] After finishing the arc surface, use a tool slightly larger than the diameter of the glue hole to drill the glue hole. The drilling depth is to the bottom of the process table to remove the material in the adhesion area between the process table and the workbench to facilitate the disassembly of parts.

[0049] If the cavity surface is milled first and the bottom of the part is left hanging, the cutting force during machining will accumulate along the long direction of the arc surface, and the cutting force will reach its highest value at the top of the part, causing brittle fracture of the part.

[0050] S4. Rough machining of cavity surface: level the reference surface on the CNC machine tool, glue the process table and glue holes on the machine tool workbench at intervals of 200mm, and complete the workpiece clamping; use the solid hard end milling cutter specially used for the previous process for rough machining. The machining sequence is rough milling the right end bevel, rough milling the outer contour, and rough milling the process connection, leaving a uniform allowance of 2mm on one side.

[0051] S4. Finishing the cavity surface: Use a small amount of cutting and fast feed process to mill parts to ensure the outer dimensions, such as Figure 6 As shown;

[0052] After finishing the cavity surface, use a tool slightly larger than the diameter of the glue hole to drill the glue hole. The drilling depth is to the bottom of the process table to remove the material in the adhesion area between the process table and the workbench to facilitate the disassembly of the parts.

[0053] S5. Blanking by fitter: On the bench, the fitter wears white gloves and uses a utility knife to cut and connect the parts in an area 5mm away from the edge of the parts. After finishing, the parts are finished.

[0054] Further, in S2, in the process block for bonding the side wall in the long direction of the blank, the order of bonding the process blocks is:

[0055] S201, firstly place the bottom surface of the process block close to the workbench, and then move the process block horizontally to close to the side surface of the blank;

[0056] S202, first use glue to bond the process block to the workbench, and then use glue to bond the process block to the side of the blank.

[0057] Furthermore, the six reference holes in S2 are auxiliary reference holes for reviewing the position status of the parts, of which two reference holes are used for part straightening and alignment and for establishing the machining coordinate system, and the remaining four reference holes are used to detect power failure, gas failure, and tool milling failure of the machine tool;

[0058] The steps for using the 6 glue filling holes in S2 are as follows:

[0059] S211, use a solid hard end mill to drill a glue injection hole on the workbench surface, and use an air gun to clean the foam dust in the hole;

[0060] S212. Use a syringe to fill the glue holes with glue. The thickness of the glue filling is 5 mm. Visually check the fullness of the glue at the bottom of the glue filling holes.

[0061] S213, use an air gun to blow dry the glue, 1 minute for each hole;

[0062] S214, pressing the process table to check the adhesion between the workpiece and the workbench.

[0063] Furthermore, a solid hard end mill with a diameter of 10 mm, a blade length of 70 mm, and a tool shank clearance of 110 mm is installed in the milling reference surface, anti-backlash angle, and through hole in S2; the milling reference surface, anti-backlash angle, and through hole are divided into milling process and drilling process, and the milling process adopts a spindle speed of 12000 r / min and a feed speed of 20000 mm / min; the cutting width is 10 mm and the cutting depth is 70 mm; the drilling process adopts a spindle speed of 3000 r / min and a feed speed of 200 mm / min.

[0064] Furthermore, in S3, a solid hard end mill with a diameter of 12 mm and a tip radius of R1 mm is used for finishing the milling of the arc surface; the milling process uses a spindle speed of 12000 r / min, a feed speed of 20000 mm / min, a cutting width of 1.2 mm, and a cutting depth of 25 mm; the drilling process uses a spindle speed of 3000 r / min and a feed speed of 200 mm / min.

[0065] Furthermore, the specific steps of rough machining the cavity surface in S4 are:

[0066] S41, rough milling the right end inclined surface: use a special solid hard end mill to cut outside the processing area, reciprocate along the long direction of the inclined surface of the part to process the bevel of the part, such as Figure 7 As shown;

[0067] S42, rough milling of the outer contour: using a dedicated solid hard end mill full-edge cutting process method, milling out 80 30×15mm process connection ends;

[0068] S43, Milling process connection: Use full-edge cutting process method to mill out 80 process connection ends to ensure the thickness of 5mm.

[0069] Furthermore, the finishing of the cavity surface in S5 uses a solid hard end mill with a tool diameter of 12 mm and a tool tip radius of 1 mm; the milling process uses a spindle speed of 12000 r / min; a feed speed of 20000 mm / min; a plane cutting width of 1.2 mm; a plane cutting depth of 5 mm; a chamfer cutting width of 11 mm; and a chamfer cutting depth of 0.25 mm.

[0070] It is to be understood that the present invention is described by some embodiments, and it is known to those skilled in the art that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. In addition, under the teachings of the present invention, these features and embodiments may be modified to adapt to specific circumstances and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the scope of protection of the present invention.

Claims

1. A method for processing aviation foam parts, characterized in that: The following steps are involved: S1. Arrangement: Arrange parts according to their maximum contour, arrange parts with the same height on the same foam blank, set the lower groove width to 15mm, and the process table thickness to 20mm; S2, milling reference surface and anti-reverse angle, through hole: glue the blank to the machine tool workbench at intervals of 200mm around the blank, and the bonding range should not exceed 10×10mm; if the gap of the blank warping deformation is greater than 0.5mm, it is necessary to glue the process block on the side wall in the long direction of the blank; the top surface of the process block should be greater than 10mm away from the reference surface; Drill 12 symmetrical through holes, of which 6 are reference holes and the other 6 are glue holes. The distance between the glue holes is 200mm. The process table and the workbench are bonded to ensure that the clamping force is dispersed to each supporting surface of the process table, reducing the risk of part cutting vibration and brittle fracture. The six reference holes are auxiliary reference holes for reviewing the position status of the parts, of which two reference holes are used for part straightening and alignment and for establishing a machining coordinate system, and the remaining four reference holes are used to detect power outages, gas outages, and tool milling failures of the machine tool; The steps for using the 6 glue injection holes are as follows: S211, use a solid hard end mill to drill a glue injection hole on the workbench surface, and use an air gun to clean the foam dust in the hole; S212. Use a syringe to fill the glue holes with glue. The thickness of the glue filling is 5 mm. Visually check the fullness of the glue at the bottom of the glue filling holes. S213, use an air gun to blow dry the glue, 1 minute for each hole; S214, pressing the process table to check the adhesion between the workpiece and the workbench; S3, Finishing arc surface: The highest point of the arc surface of the part is 1mm away from the reference surface as the cutting point, and the area within 3mm of the maximum outer contour of the arc surface is reciprocated along the long direction of the reference surface to ensure that the reference surface provides stable support for the efficient rough machining cavity when using a smaller thickness blank; After finishing the arc surface, use a tool slightly larger than the diameter of the glue hole to drill the glue hole. The drilling depth is to the bottom of the process table to remove the material in the adhesion area between the process table and the workbench to facilitate the disassembly of parts. The finishing milling of the arc surface adopts a solid hard end mill with a tool diameter of 12mm and a tool tip radius of R1mm; the milling process adopts a spindle speed of 12000r / min and a feed speed of 20000 mm / min; the cutting width is 1.2mm and the cutting depth is 25mm; the drilling process adopts a spindle speed of 3000r / min and a feed speed of 200mm / min; S4, rough machining of cavity surface: level the reference surface on the CNC machine tool, glue the process table and the glue injection hole on the machine tool workbench at intervals of 200mm, and complete the workpiece clamping; use the solid hard end milling cutter dedicated to the previous process for rough machining, and the machining sequence is rough milling the right end inclined surface, rough milling the outer contour, and rough milling the process connection, leaving a uniform allowance of 2mm on one side; The specific steps of rough machining the cavity surface are: S41, rough milling the right end inclined surface: use a special solid hard end mill to cut outside the processed area, reciprocate along the long direction of the inclined surface of the part to machine the bevel of the part; S42, rough milling of the outer contour: using a dedicated solid hard end mill full-edge cutting process method, milling out 80 30×15mm process connection ends; S43, milling process connection: adopt full-edge cutting process method, mill out 80 process connection ends, and ensure the thickness size of 5mm; S5. Finishing the cavity surface: Use a small cutting amount and fast feed process to mill the parts to ensure the external dimensions. After finishing the cavity surface, use a tool slightly larger than the diameter of the glue hole to drill the glue hole. The drilling depth is to the bottom of the process table to remove the material in the adhesion area between the process table and the workbench to facilitate the disassembly of the parts. S6. Blanking by fitter: On the bench, the fitter wears white gloves and uses a utility knife to cut and connect the parts in an area 5mm away from the edge of the parts. After finishing, the parts are finished.

2. The method for processing aviation foam parts according to claim 1, characterized in that: In the process block for bonding the side wall in the long direction of the blank in S2, the order of bonding the process blocks is: S201, firstly place the bottom surface of the process block close to the workbench, and then move the process block horizontally to close to the side surface of the blank; S202, first use glue to bond the process block to the workbench, and then use glue to bond the process block to the side of the blank.

3. The method for processing aviation foam parts according to claim 1, characterized in that: The milling reference surface, anti-backlash angle and through hole in S2 adopts a solid hard end mill with an installation diameter of 10mm, a blade length of 70mm and a tool bar clearance of 110mm; the milling reference surface, anti-backlash angle and through hole are milling and drilling processes, and the milling process adopts a spindle speed of 12000r / min and a feed speed of 20000 mm / min; the cutting width is 10mm and the cutting depth is 70mm; the drilling process adopts a spindle speed of 3000r / min and a feed speed of 200mm / min.

4. The method for processing aviation foam parts according to claim 1, characterized in that: The finishing of the cavity surface in S5 uses a solid hard end mill with a tool diameter of 12 mm and a tool tip radius of 1 mm; the milling process uses a spindle speed of 12000 r / min; a feed speed of 20000 mm / min; a plane cutting width of 1.2 mm; a plane cutting depth of 5 mm; a chamfer cutting width of 11 mm; and a chamfer cutting depth of 0.25 mm.

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