Parameter of high speed cutting optimizes the application of processing technique

To satisfy modern plane concealed body, supersonic fast cruise, exceed groovy motor-driven, Gao Xin news perception ability, macrobian life, structure is light quantify the function that waits for a respect to ask, new technology, new structure, new data was used in great quantities in the design, structural member also day trend size is large change, the structure complications, make change development accurately [1] . The development trend of structural member decided its craft characteristic: The structure is complex, treatment difficulty is great; Cutting treatment amount is large; Bao Bi, changeful form; Requirement of spare parts production precision is advanced. Implementation high accuracy, efficient to structural member of whole of this kind of aviation the cutting treatment with high reliability is a when aviation manufacturing industry is faced with main task all the time. As the development of technology of high speed cutting, treatment of high speed cutting machines effect to lead force of tall, cutting to the heat of small, workpiece is out of shape and be heated up with its expand good, economic benefits reachs mass of surface of small, treatment high appropriate treatment is sophisticated with long and thin Bao Bi wait for distinct advantage, in the treatment that is used extensively at aerospace whole structural member [2] . Processing technique of high speed cutting is to be in design of system of control of system of machine tool structure and material, high speed main shaft, fast feed system, high-powered CNC, machine tool makes technology, high-powered knife place material of system, high-powered cutting tool and cutting tool to design production technology, efficient high accuracy to check cutting of technology, high speed. It has treatment effect to lead force of tall, cutting precision of small, treatment and exterior quality are advanced characteristic, already mixed in aviation, spaceflight, car, mould the industry such as accurate machinery got applied extensively, obtained major economic benefits. The emulation that the core of processing technique of high speed cutting is cutting parameter is optimized. The exploration of parameter of high speed cutting was experienced from copy common cutting to machine parameter (treatment efficiency is low, bao Bi machines exterior quality to differ) , use try cut a method to get high speed to machine cutting parameter (requirement of can contented quality, efficiency rises somewhat, cost is high, cycle is long) process. Be in at present home, most aviation industry used the method that is based on kinetic emulation technology to optimize cutting parameter, changed a tradition to get the means of cutting parameter. High speed milling machines treatment of cutting of kinetic emulation high speed to want to have high main shaft rotate speed, rotate speed of general main shaft is in of 10000~20000r/min above for high speed cutting; Feed rate is very high, amount to 15~50m/min normally, highest can amount to 90m/min. But after the main shaft rotate speed that if be in treatment,increases a machine tool purely and feed speed, with respect to the vibration that can bring mill to cut the cutting tool in machining a process or work, namely flutter phenomenon. Flutter is phenomenon of a kind of when arise between the cutting tool in metallic cutting process and workpiece relatively intense self excited vibration. The occurrence meeting of flutter brings about cutting force peak value to increase apparently, make machine exterior surface roughness and dimension precision to drop apparently, serious when can make cutting tool burst, main shaft is damaged; Can cause certain pollution to machining an environment normally in addition [3] . How to solve afore-mentioned problems to become the difficult problem that high speed cutting studies, then Beijing aerospace university passed the problem that machines occurrence flutter to high speed cutting to undertake study, put forward to be based on the theory that parameter of true treatment of high speed cutting optimizes kinetic copy, after stabilizing region through finding the flutter of cutting, undertake optimizing to cutting parameter, solved the flutter problem that high speed cutting brings. Stable region is flutter to have consideration to the stability of milling process flutter inside frequency domain namely, give out the stable area of cutting process (deepness of main shaft rotate speed, cutting) [3] . And be based on kinetic copy parameter of true high speed CNC machining optimizes a technology is through be opposite " main shaft + cutting tool (geometry, material) + workpiece (material) " the CNC Machining machining complex that form has test of systematic mode parameter and cutting process kinetic emulation computation, get flutter of power of torque of cutting force, cutting, main shaft, cutting to stabilize the mechanical information such as region, optimize software to realize parameter of pair of cutting of high speed CNC Machining through cutting parameter optimize [4] . If use numerical control machine tool to machine kinetic characteristic test to analyse a system,high speed milling machines kinetic copy Allah (DynaCut software) generate frequency noisy function and mode parameter, process kinetic emulation system in milling next (SimutCut software) in, combinative frequency noisy function and mode parameter undertake flutter stabilizes region and time domain to emulate, get cutting power / cutting torsion / cutting power / the time domain information such as cutting ply and curve of flutter stability region, output file of emulation data table, choose optimized cutting parameter according to emulating data table file finally, the cutting parameter such as deepness of rotate speed of first-rate machine tool, cutting is chosen in making the spare parts is machining a process [5-8] . The application of processing technique of high speed cutting on wainscot of large and complex whole short for Shaanxi Province of brief introduction of 1 whole wainscot flies to a company some model machine whole wainscot, used large size, big ply, become sectional belt length joist, belt maintains design of shape of buccal casing reseau, central ala length is close 4.

6m, length of ala of China and foreign countries is close 10.

8m, use 5 whole wainscot on 3 times to divide a distribution, complete machine shares 24 wainscot. If wainscot structure pursues 1, the graph is shown 2 times, and put in following difficulty: Rate of purify of Nextpage · material is old. The material of integral wainscot uses Russian aluminium, 1973T2 and 1611T, beforehand drawing extruding plank. The largest size is material × 800mm of 11000mm × 9000mm, wollens most heft 2.

5t, material value is high, material purify rate is 90% the left and right sides. · changeful form. Spare parts structure is complex, ply dimension change is big, spare parts thick is 67mm, the smallest part is only 2.

5mm. From the point of structural tigidity, some local tigidity are very strong, and some local tigidity are very weak, stress of interior of the material when treatment is released inhomogenous, the spare parts is out of shape not easy control. · structure is complex, treatment difficulty is great. The underside of integral wainscot is wing theory appearance, magic art of wing of long joist edge cover to distributing, especially thickening spends envelope of wainscot of ala of China and foreign countries. Theoretic exterior face and alar bowstring face are not parallel. Grow joist, costal region to wait to be shown with wainscot underside change horny condition. Before flying company of short for Shaanxi Province was not using high speed cutting, wainscot of whole of ala of China and foreign countries machines man-hour to be 410h about in first spare parts, and a plane shares 24 wainscot, machine a method according to this, a machine tool can machine the wainscot of a machine 1 year only, treatment efficiency is low, affect the pay plan of the plane directly. Of program of technology of treatment of 2 high speed make machine efficiency to solve integral wainscot low be out of shape with the spare parts problem, short for Shaanxi Province flew to a company to undertake fumble and trying to processing technique of high speed cutting, through optimizing treatment technology program is mixed in the treatment process in wainscot use be based on kinetic copy the application that parameter of true high speed CNC Machining optimizes a technology, obtained better result. (1) machine plan. Machine efficiency to rise, prevent a spare parts to be out of shape, making the classics on technology program careful research, prove repeatedly, make treatment program finally be: Machine face of appearance of theory of wainscot of rework of the form inside wainscot first when machining integral wainscot, and cent rough machining and finish machining undertake; The fixed position of the spare parts uses craft protruding stage to if the graph is shown 3 times,impose the kind of craft wall. Machine means to cutting, in growing joist except wainscot " T " model groovy treatment is used " T " model the knife uses common CNC Machining outside, the others thick, precision work is same the treatment plan that adopts high speed treatment. If the graph is shown 3 times,make structure of body wainscot T chamfer. (2) integral wainscot machines specific flow. · small cutting measures surface of fluctuation of mill semifinished product; Two sides of · mill positive and negative machines standard limit; 3 axes of · are thick the form inside a side of the surface on mill (high speed milling, prevent to be out of shape) ; 3 axes of · are thick mill T chamfer; 3 axes of · are thick a side of appearance of theory of the surface below mill (high speed milling, prevent to be out of shape) ; Stage of protruding of craft of · mill spare parts; · essence mill leaves the outside on semifinished product; Two sides of positive and negative of · essence mill machines standard limit; 5 axes of · the form inside a side of the surface on mill of essence of life (high speed milling) ; 5 axes of · T of mill of essence of life chamfer; Mill of 5 axes essence issues · a side of exterior theory appearance (high speed milling) ; · mill appearance, next makings. Specific place is shown 4 times like the graph. Parameter of cutting of treatment of cutting of 3 high speed is decided really it is with the wainscot on 2# of the ala central exemple, its structure signal is shown 3 times like the graph, uses device is JOBS143 milling machine of high speed of numerical control of door of 5 axes dragon, material is 1973T2. (1) data is collected. Place cutting tool outfit on machine tool main shaft, be linked together equipment of sensor and cutting tool, pulse, get through be being attacked to cutting tool hammer direction of X of machine tool main shaft and Y direction hammer attack test data. Via DynaCut software processing, get cutting tool of φ 32-R3-L80 hard alloy " machine tool - cutting tool " systematic mode parameter, if express,1 is shown. (2) use SimuCut software to undertake to experimental data flutter stabilizes region analysis. Open SimuCut V1.

22, cutting tool of hard alloy of φ 32-R 3-L80 " machine tool - cutting tool " systematic mode parameter guides dynamic character commands column, input parameter of information of cutting tool, workpiece and cutting means, undertake flutter stabilizes region to emulate, generate flutter to stabilize a curve thereby, if the graph is shown 5 times, stable region is partly below the curve among them, use at parameter of preliminary and affirmatory cutting. Nextpage stabilizes region curve according to gotten flutter, parameter of preliminary and certain technology, if express,2 are shown. (3) generate kinetic time domain to emulate. Through inputting coefficient of material of cutting tool parameter, choice, and the cutting parameter related the input, undertake cutting force is emulated, generate time domain to if the graph is shown 6 times,be emulated. (4) the cutting parameter that the choice optimizes undertakes machining. The ability that machines equipment data, actually according to generated emulation analysis (equipment parameter sees a table 3) and the actual and particular case of my group, undertake optimizing to preliminary and affirmatory craft parameter, the cutting parameter that chooses to optimize machines this spare parts. Decided what cutting tool of hard alloy of use φ 32-R 3-L80 machines finally to optimize parameter according to this method: N of main shaft rotate speed: 12000r/min; Feed speed F: 4800mm/min; C of every tine feed: 0.

2mm/z; Cut wide Ae: 32mm; Cut deep Ap: 5mm. (5) use the efficiency contrast that before optimizing, undertakes machining with parameter of the cutting after optimizing. According to machining the effective treatment after before parameter is optimized, be being optimized with parameter to the spare parts data has statistic, the cutting handling time that place of this norms cutting tool uses to need before this spare parts is machining parameter to optimize is 9.

38h, and use the cutting parameter after optimizing to undertake machining, time shortens for 4.

14h, make the treatment efficiency of this spare parts rose thereby 127% . Use this method to be opposite all treatment integral wainscot cutting tool of the ala undertook flutter stable region is analysed and machine craft parameter to optimize in the center of this, make time of machining of central ala wainscot decreases by original 180h 60.

05h, at the same time of the spare parts be out of shape rate is apparent reduce, the spare parts machines quality to get rising significantly, benchwork burnish workload decreases 60% the left and right sides. The last word uses processing technique of high speed cutting, make the cutting of wing whole wainscot machines efficiency to rise greatly, assured the manufacturing form a complete set of plane whole wainscot, the treatment quality that improved wainscot of whole of ala of large scale computer at the same time, reduced spare parts treatment to be out of shape; The research of processing technique of high speed cutting offerred effective method and way for the treatment of part of whole of large and complex Bao Bi; The research of processing technique of cutting of high speed of wainscot of large and complex whole uses the aircraft, bridge of costal region of the casing of large whole end that carries for sequel 8 series model reachs ongoing aircraft, whole, whole, connect begin high speed efficient cutting treatment laid solid foundation. CNC Milling