CNC Machining equipment and advanced processing technique

1mm, plane of the generation before comparing raises one times above. Afore-mentioned development trends of the structural member of craft characteristic aviation of 2 aviation structural member decided its craft characteristic: The structure is complex, treatment difficulty is great -- spare parts appearance involves the complex and academic external form such as appearance of airframe appearance, wing appearance and area of alar body confluence, and need to undertake covering closing with many spare partses; Cutting treatment amount is large -- material purify rate achieves 90% above, partial part is achieved even 98% ; Bao Bi, changeful form -- put in structure of many Bao Bi, deep antrum, for typical weak rigid structure; Treatment precision is tall -- assemble the amount such as harmonious face, nodical aperture much, demand of spare parts production precision is high; Proportion of difficult treatment material is large -- the proportion of difficult treatment material that is a delegate with titanium alloy, composite material is larger and larger, posed grim challenge to aviation manufacturing industry. Equipment of CNC Machining of aviation structural member expands the directional rapid development as aviation industry, on one hand, size of plane structural member is larger and larger, the structure is more and more complex; Treatment precision is taller and taller; On the other hand, proportion of difficult treatment material is higher and higher in plane structural member, make treatment efficiency progressively become the crucial factor that restricts plane development and batch production. To get used to the requirement of CNC Machining of efficient, high accuracy of aviation structural member, the characteristic such as high speed, high spirit, intelligence, compound, environmental protection became implementation the main development direction that CNC Machining of modern plane structural member equips. Treatment of 1 high speed is the processing technique of main avenue high speed that realizes efficient treatment not only twice land improves the manufacturing efficiency, treatment precision that improves a spare parts and exterior quality, and a few solves hard problems in solving low speed effectively to machine: Certain and the treatment that implements ultrathin part for example, special material (if fiber increases plastic wait) efficient treatment. High speed treatment still is to realize these plane structural member at present the main avenue of efficient treatment. In recent years, the technology got swift and violent development related high speed treatment, the each function index that reflects high speed process capability rises ceaselessly. The high speed main shaft of current application, rotate speed can amount to 420000 R/min, taller even; Linear electric machinery and pitching moment electric machinery already entered applied phase stage by stage, feed rate is rapidder and rapidder, achieve 120m/min; Feed acceleration is bigger and bigger, acceleration of feed of bed of large scale computer is achieved 9.

81m/s2, medium or small acceleration of machine tool feed is achieved 19.

62m/s2, mirror what acceleration change leads to add acceleration (Jerk) already became a when measure high speed performance main target; Cutting efficiency is taller and taller, the material purify rate of CNC Machining of aluminium alloy structural member is as high as 5000 ～ 7000cm3/min. Current, the high speed that is a delegate with the Ecospeed series machine tool that company of German DS Technologie manufactures main shaft of machine tool of 5 coordinate paralell connection swings speed achieves 80 ° / S, acceleration achieves 685 ° / S2, outclass strings together online bed commonly; Speed of shift of its linear axis exceeds 50m/min, acceleration is achieved 9.

81m/s2; Main shaft is highest rotate speed 30000r/min, power achieves 80kW, in production of structural member of aviation aluminium alloy metallic purify rate can amount to 7000cm3/min, representing the top level that high speed of current aviation structural member machines undoubtedly. In the meantime, as the ceaseless development of machine tool technology, main shaft of high speed report also begins to apply at the efficient treatment of titanium alloy stage by stage, the main shaft of high speed report that the H22-3R horizontal machine tool that manufactures like INGERSOLL company used OMLAT, main shaft is the 10000r/min of top rotate speed, largest torque 830Nm, when 1000r/min torque can maintain in 400Nm, when 3000r/min power still exceeds 150Nm for 45kW, torque, for titanium alloy efficient treatment provided good hardware basis. Equipment of Nextpage2 aviation numerical control is progressively nicety changes what ask as plane whole function to rise, plane structural member to dimension the way with bigger, taller precision develops, the accurate treatment of large structural member is the challenge that efficient CNC Machining must face implementation plane structural member. And as character of base of numerical control machine tool is large structure and thermal stability rise, the breakthrough that technology of full closed-loop control, temperature compensates technology, online monitoring technology to wait in real time, can make numerical control machine tool obtains better treatment precision. Current, the arrange almsgiver that raises machine tool precision wants to have: The casing in casing heats up symmetrical structure design, can acquire tall tigidity, high accuracy and low mobile quality; Finite yuan the structure optimizes a design, make tigidity of machine tool structure distributings equably, natural frequency raises 3 ～ 4 times, reduce vibration, raise the surface to machine quality; Undertake temperature is controlled and be compensatinged in real time to calorific component; Sum of errors of precision of machine tool geometry is hot be out of shape real time monitoring and compensation. The application of these technologies makes machine tool precision rises greatly, machine tool of numerical control of class of current offer rice already aborning gets applied, most typical delegate is the accurate boring milling machine of Swiss DIXI company: ≤ of fixed position precision 0.

8 μ M, repeat ≤ of fixed position precision 0.

1 μ M. The intelligence that 3 aviation numerical control equips is changed, flexible the meet an emergency that changing intelligence of numerical control machine tool is the generation in showing numerical control machine tool can obtain treatment process, oscillatory, heat is out of shape wait for the information related to treatment, be compensated automatically and optimize a machine tool to machine function, in order to improve quality of treatment precision, surface and treatment efficiency. Current, a lot of machine tools are progressively and compositive Artis from adaptive control system, can pass monitoring of machine tool main shaft not only (cutting tool detects evenly, conflict detects, bearing detects etc) reach cutting tool monitoring (damaged detects, wear away detect etc) the overload protection that realizes cutting tool, machine tool, and can reach a system through machining the data in the process to collect automatic judgement has adjusting control of real time speed, realize the efficient treatment of stable load thereby. To improve utilization rate of equipment and installations and CNC Machining efficiency further, aviation manufacturing industry begins a large number of introducing flexible production unit (FMC) reach flexible production system (FMS) , and horizontal machining center and stand lie changeover machining center discharges bits function as a result of its good, in flexible production unit and flexible more wide application received in production system. Be in flexible in production system, many treatment facilities and cutting tool are online detect, treatment coordinate department searchs automatically to assisting device to be united in wedlock together to be able to realize efficient automation to machine: Automatic exchange and implementation of the system that hold clip machine workbench of the spare parts change automatically; Treatment coordinate department searchs what the system uses the implementation that measure a head to machine coordinate to fasten is automatic search, set and compensation; Online testing system realizes cutting tool to undertake detect and be inputtinged automatically to using the main parameter such as the length of cutting tool, diameter, undertake to cutting tool error according to using a requirement compensation or condition are judged. The new development of CNC Machining technology is large the CNC Machining of aviation structural member, the key depends on quality and efficiency. And the main factor that restricts CNC Machining quality and efficiency, depend on condition of machine tool hardware on one hand, and more important what still depend on propping up efficient CNC Machining is relevant make can technology, if cutting tool technology, tool technology, craft is designed,reach emulation technology to wait. The technology of development cutting tool of technology of 1 cutting tool is one of crucial technologies of CNC Machining, also be the bottleneck of a technology that restricts difficult treatment material to machine efficiency. As the progress of cutting tool technology, structure of cutting tool material and cutting tool is improved ceaselessly, cutting tool sort is increasing, how logical choice cutting tool and cutting parameter are the core place that improves CNC Machining efficiency. The respect is machined in aluminium alloy material, technology of high speed cutting has received comprehensive application, many in process of high speed rough machining application but dislocation high speed establishs milling cutter, the metallic purify that can achieve 6000cm3/min on machine tool of high-power high speed is led, finished cost is attainable also effective control; Cutting tool of integral hard alloy is the main cutting tool that high speed of current aluminium alloy machines, the precision work that basically is used at aluminium alloy spare parts or narrow thick finish machining of groove, the exterior quality that can have acquired has longer cutting tool life. And pottery and porcelain, diamond and cubic nitrogen change boron to wait exceed strong cutting tool to have extremely tall wearability, accept the restriction of cutting speed scarcely, cutting fights force small, did not accumulate bits tumour, can the treatment efficiency of machine tool of high speed of utmost ground play, special agree with the high speed treatment of aluminium alloy, the first selection cutting tool that makes treatment of aluminium alloy high speed stage by stage. The respect is machined in titanium alloy material, because the cutting processability of titanium alloy is poorer (its are in relative to cutting sex 0.

15 ～ 0.

25 between) , speed of the cutting when using a tradition to machine means does not exceed 50m/min commonly, rate of excision of rough machining metal does not exceed 40cm3/min commonly, rate of excision of finish machining metal does not exceed 10cm3/min. Current, production enterprise has begun a few aviation of domestic to explore and apply titanium alloy efficient treatment method: Rough machining is used but the puissant cutting that dislocation corn milling cutter realizes to cut deep, small feed greatly, this cutting tool avoided effectively to be hanged greatly extend cutting tool in machining a process brace up quiver phenomenon, establish milling cutter to machine efficiency than common cylinder taller; The cutting tool that insert mill is used to undertake machining to round horn first before finish machining, make finish machining surplus even; Cutting tool of PVD coating hard alloy is used to undertake in finish machining process small cut wide, big cut deep high speed milling (cutting speed achieves 170m/min) means, make finish machining time shortens 60% above. The development of Nextpage2 tool technology is current, the way holding clip of structural member of domestic large aviation is relatively single: Aluminium alloy structural member basically uses obligate craft side piece, use bolt impaction or vacuum adsorption; The difficult treatment material such as titanium alloy basically uses pressing plate impaction; Beehive core material basically uses solid of felt of double-faced adhesive plaster to hold. And numerical control developed country already used the automatic clamping apparatus that takes pneumatic, hydraulic pressure and control system in great quantities. Use numerical control many a little bit of adsorption of self-adjusting, vacuum or mechanical collet flexible clamping apparatus, the flexible, fast fixed position that can realize the large structural member of pair of different figure to go up in the machine tool and outfit are placed, already became numerical control tool to devise made development way, it is the another crucial technology that improves CNC Machining efficiency. This technology is machining Bao Bi structural member, large answer material structural member and envelope kind the advantage when the spare parts particularly apparent. Current, industry of domestic share aviation already began to introduce contain flexible the treatment that the equipment of special numerical control of clamping apparatus has composite material. The respect is machined in beehive core material, zhejiang university excogitates a kind of high speed that is based on strong magnetic field and tribology principle to machine solid to support a method, develop a corresponding tool, obtain favorable applied result, the quality of nest core and efficiency all have treatment bee to promote considerably. 3 technology design and Cheng of emulation technology craft make up personnel to make full use of the whole process that all sorts of technology natural resources have spare parts craft and numerical control to program is numerical control craft to design namely, it affects a spare parts to produce plan and the quality that the spot machines directly, it is the link with crucial production of whole numerical control. The is much breed, small lot normally production task that aviation manufacturing industry faces, task of new machine development is onerous, design of numerical control technology already was become restrict numerical control to produce new " bottleneck " . Here setting falls, domestic aviation industry develops the efficient Cheng that is based on knowledge to invent technical research in succession, become joint development of relevant school of flying company and country among them the fast Cheng that is based on three-dimensional feature organizes a system, this system falls in CAD/CAPP/CAM compositive environment, it is a foundation in order to machine a feature, realized the fast process designing to plane structural member. At present this system already completed development and score success of test and verify. Foreign circumstance, after door subsidiary buys UG on the west, devoting oneself to to build fictitious environment (craft designs an environment) with real environment (effective treatment environment) without seam platform, in order to realize CAM-CNC compositive: In the workshop digitlization cooperates with below platform, information of system of the machine tool in coming true to design a process in craft (if life of setting of systematic kernel, precision, high-quality instruction, cutting tool manages,wait) compositive, in CNC upright implementation is in the line is emulated and of workpiece online detect, answer information feedback CAM system. This purpose is carried out facilitate not only technology design is as compositive as what process information actually, also will promote NC the efficiency of to program and quality considerably at the same time. The copy of CNC Machining process is really fictitious one of core technologies of production technology, main component is emulated for geometry and physics is emulated. The CNC Machining that at present domestic aviation manufacturing industry undertakes emulates the level that still keeps in geometry to emulate only to go up, its action basically is problem of collision of the validity that checks contrail of cutting tool of numerical control program and geometrical interference, and should realize more accurate emulation to must be opposite the physical phenomenon in machining a process undertakes study. Abroad studies in physical emulation technology the respect starts earlier, already developed corresponding emulation software, wait like Cutpro, MetalMAX, AdvantEdge, make the earliest in the aviation such as Boeing, Pu Hui success application receives in the enterprise, already used the many production fields such as cutting tool, car, mould now. Home, the person such as Beijing aerospace university Professor Liu strong developed a milling treatment is kinetic emulate optimize systematic SimuCut, what this system can realize milling process is mechanical emulate those who reach cutting parameter to optimize a choice, already received success application in war industry industry. Cutting of vibration of technology of 4 other and relevant forward position is in cutting tool (tool) or add on workpiece the low frequency of one or more different way, intermediate frequency or supersonic vibration, make the tradition closes cutting area treatment turns cutting into the area periodic the interrupted cutting process of the discontinuous, instant that open, move back and forth. Compare with common cutting photograph, oscillatory cutting has cutting power quality of surface of low, workpiece carries small, heat in metal cutting significantly advanced advantage, there was wide application in the domain such as bore, tap, milling, turning, grinding at present, it is direction of a of machining significant progress. The beehive core with foreign relatively successful application is supersonic cut, its cut force is small, cut precision is tall, cut brim is flowing, without damaged drossy, can solve difficult problem of processing technique of beehive core featheredge well. Additional, green creates the advanced production pattern that considers environmental influence and resource efficiency integratedly as a kind, already became the vane that manufacturing industry develops stage by stage. Current, industry of domestic share aviation is passing high speed processing technique, minim hard lubricant technology (MQL) , become all sorts of group of ways such as processing technique, make stride to green stage by stage. CNC Milling CNC Machining