The high speed of plane frame spare parts is machined

Content summary: Develop the latent capacity that high speed machines adequately to be in the production of component part of plane airframe whole, should the process that will include cutting process, collateral project and clamping apparatus to be conceived inside considers as a whole. Structural member is a kind of the largest part in aircraft spare parts. This kind of spare parts basically is made with aluminium alloy. Be based on workmanship and consideration of spare parts weight, aluminium board basically is used to be become via riveting previously (up to now still partial part uses this kind of method to make) . Adopted the design technique that differs right-down now, need general a variety of different functions are compositive go up to a structural member. This is compositive design technology. This kind of spare parts is to use a hypostatic aluminium to base classics milling is machined and be become. This kind of part is very complex, the underside that includes minimum normally and thin wall (0.

6~2mm) , submit honeycomb form. The geometrical appearance of this kind of spare parts is formed by the curved surface of different face and regulation. Be close to a plane the surface of exterior outline also is must be free curved surface. Graph the girder of plane of Pilatus PC 9 of 1 whole structure (the picture offers: StarragHeckert company) for example, the girder of plane of Pilatus PC 9, forming by 156 different spare partses in the design previously. Such, with respect to need all sorts of equipment that fold a turn are mixed assemble clamping apparatus. On plane of Pilatus PC 12, this kind of component used compositive design technology. The amount of the spare parts reduces 3, and it is to use simple bolt to join (graph 1) . Before 25 years, when this aircraft company is developing an aircraft, because do not have complex software tool, NC technology still is in primary level, can use trival programming language only, if APT, Fortran defines complex geometrical form etc; NC machine tool still uses 21/rD to control, recruit those who made complex form face and geometrical appearance badly to generate thereby. As a result of some kind of reason afore-mentioned reasons, to control aluminium weight, use aluminium board to make frame, be about to the plank of more than kinds of 20 different figure shapes assemble and join makes an old structural member together. The spare parts shapes the process is very complex. Workpiece material should pass machining and 4 heat treatment 12 times, the abhorrent, drawing as a result of geometrical appearance / rupture etc, cause percent defective extremely tall. The assembly of this kind of frame needs 6 working procedure, and the drawing issue that must consider data. Nowadays, process designing system and CNC machine tool can have made our milling treatment gives the appearance that cannot make before. Previously, use conventional technology, need 20 many plank to shape a part that ability makes, use 2 parts only now. Geometrical form is very complex, must satisfy all requirements of the spare parts completely. With a hypostatic aluminium base mill makes a part, among them the material of 98% became useless bit. The professional knowledge requirement that process of process designing of NC of treatment of the 3 situations product that finish needs is highest, all sorts of the requirement is compositive differring manufacturing technology: Design of cutting tool of CAD/CAM, cutting, clamping apparatus and milling technology. Need working procedure of 3 be sanctimonious to be able to make a parts of such a frame only now: 1) gets a course beforehand cutting contains clip to manage the raw material that uses opening, 2) milling spare parts, 3) hand is moved get a rivet aperture (use clamping apparatus) . Spare parts burr is finished in machining a process. After first item inspection is eligible, milling machines a process to undertake automatically, need not operator interpose. Simplified greatly so of dimension and crackle detect, compare with the production method photograph previously, reduced manufacturing cost. Compositive structure still is assembled to the spare parts have major effect. Whole module (component) can assemble directly. Makes spare parts common difference is very strict, have very good interchangeability. Assemble precision to get assuring, and the process is stable, shortened substantially needs assembly time. Graph 2 special agree with the STC 1000/130 machine tool of the StarragHeckert company that 5 axes linkage machines, when power is 70kW, main shaft rotate speed is 24, the machine tool that 000r/min applies to high speed milling and cutting tool preform are the knife that use water the aluminium of will thick 127mm or 76mm board be sure to cuts similar figure. Preform dimension is 840 × 665mm, weigh 90kg or 60kg. Clamping apparatus includes angle board and standard aperture department and treatment work the 2nd vacuum joint is comfortable match board. The machine tool uses special the Sidalagehaikete that applies to treatment of 5 axes linkage STC 1000/130 machine tool: Main shaft power is 70kW, 2) of graph of 24000r/min (of highest when 100% load move turn up; Main shaft taper hole: HSK63A; Journey of axis of machine tool X/Y/Z is: 1700mm/1600mm1950mm; Main shaft but bend limits: - 60/+100 ° ; Workbench is B axis. This machine tool uses armor plate to solder structure, have taller stiffness. Whole treatment process needs 7 cutting cutting tool and 4 bit. Cutting tool is integral cutter hub, the biggest diameter is 32mm, the razor blade that appearance cooperates can prevent his to leave the damage that mental efforts may cause when the rotate speed cutting with be as high as 24000r/min. Diameter of all cutting tool is in 25mm above, hollow and cooling, oily mist is lubricant. At first diameter is less than the cutting tool of 25mm to be knife of integral hard alloy, use contractive type knife handle. Cutting tool length is 90 with 220mm.

. Knife handle of along with of overall cutting cutting tool passes a balance, when 24000r/min turns balance quality is Q2.

5. To assure to machine the safety of the process, defined the cutting parameter of every cutting tool accurately, use special software namely, had knowledge to cutting tool component critical speed (from brace up) detect. The spare parts completes full treatment via holding clip 2 times (include riveting aperture) . To prevent Bao Bi the stress in treatment is out of shape and assure strict pilot public errand, face mill and circumjacent milling used high speed milling to machine craft. Inside total milling handling time, the time of about 60% needs treatment of 5 axes linkage, 40% what rough machining takes total handling time, the hand uses treatment basically is to go burr and drill partial rivet hole. When the graph holds clip 2 times 3, use one special work comfortable the technology that mixes clamping apparatus clip to hold a spare parts to already machined a face to go up is built child the result anticipates more than secure work with bolt above all go up in clamping apparatus, measure head identifying part with Leinishao. Working procedure of the first be sanctimonious is the knife head that uses diametical 63mm, edge Z scale moves, workpiece thick mill comes adjacent and final figure. The feed speed when thick mill can amount to 17m/min, metallic excision rate amounts to 6500mm3/min. The 2nd working procedure is to use 25mm whole hard alloy to establish milling cutter thick mill to give spare parts appearance. Because face of this one outline is curved surface, want to use 5 axes linkage to machine ability to obtain unanimous finish machining consent to differ. Establish milling cutter with hard alloy of diametical 16mm whole subsequently, give a quantity to have precision work to this appearance with the feed of 9m/min () of 5 axes linkage. 2 outfit of the spare parts place treatment to also use same clamping apparatus. When holding clip 2 times, use special work comfortable the technology that mixes clamping apparatus clip to hold a spare parts to already machined a face to go up is built child (graph 3) . Its the first working procedure still is the milling cutter that uses 63mm, along Z face thick mill gives spare parts rough sketch, the treatment method that also holds clip with afore-mentioned first time with foreword of come off work is same. Subsequently finish machining is very crucial. Right now, the spare parts has become paper-thin, extremely easy damage leaves in vibration. To prevent attaint spare parts, spare parts outline should be machined first when finish machining, rework groove. Last working procedure still includes to use 10mm of a diameter to establish milling cutter to take spare parts and technology child detached. With respect to the spare parts treatment case looks, to this kind of new-style plane, each result all is head and shoulders above expect a demand. What machine the spare parts precision that go out to be located in completely inside the limits of strict public errand of the requirement, have complete interchangeability. Whole production cycle shortened 75% reduced manufacturing staff. Because adopt successive treatment chain, can realize sudden shift and simplified content sheds chain. CNC Milling