The technology studies key of milling of aluminium alloy high speed

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The KR214 of machining center of milling of 6 coordinate high speed that A company produces, this equipment main shaft can come true double swing, workbench amount to accuses circumgyrate workbench, main shaft is highest rotate speed 24000rpm, those who use is system of FIDIA C20 numerical control, this machine tool basically is used at machining some whole cabin paragraph. Integral cabin paragraph the aluminium alloy forging that the structure is cylinder and cone, two end carry casing to add configuration of the envelope intermediate, the surface outside cabin body has opening of ellipse of all sorts of U chamfer, square aperture, round Kong He; Inside model two end have the side inside U handle; Cave in, annular muscle, two end panel have lacy with butt joint aperture, envelope ply is 3mm commonly. Inside model the space is lesser, structure complex, wall thin, treatment face is much. Head of main shaft of linkage of complex, much axis, machine tool enters cutting tool contrail knife of the treatment inside cabin body, advance and retreat produces risk of collision and interference phenomenon, treatment implementation, easily to wait for a characteristic greatly hard. Be aimed at above problem, the article studied cabin style is much a few crucial technologies of milling of axial high speed. Milling of high speed of engineering technology of milling of 1 high speed because its cutting speed force of stability of tall, cutting, cutting is small, special apply to treatment to produce product of heat build-up metabolic easily. The Bao Bi in the product that my factory produces more (buccal casing, bracket) , machine milling method commonly, the spare parts is out of shape big, form tolerancepublic errand assures not easily, take the kind that increase effectiveness for a given period of time or machines repeatedly for many times more but assure product quality very hard still, and working procedure is longer, treatment cycle is long. Deepness of cutting of high speed cutting and cutting force are small, make cutting tool, workpiece is out of shape small, maintained the accuracy of dimension, also make cutting destroys a layer to attenuate, leftover stress is little, agree with machine Bao Bi. Be aimed at the craft characteristic of high speed milling, with body of 3 kinds of large circle, thin wall (dimension is in 400 above of 700 × ) for the object, undertake craft experiments, fumbled technological process, achieve reduce process, improve quality, shorten periodic purpose. 1) flatness of high speed mill can be achieved 0.

02mm above, general and planar treatment can replace the working procedure that establishs Che Pingduan range; 2) Bao Bi treatment outfit clip is very important, general extruding type presses type to be out of shape than going up small; 3) rough machining is the quantity of the biggest excision inside pursuit unit time, not tall to exterior quality and precision requirement, important is to let a machine tool balance the job, avoid the sharp change of cutting direction; 4) semifinishing machining is for before the remain after line working procedure is machined becomes flowing, surplus is even. Answer because of this semifinishing machining along the ship milling after rough machining, cut process stability, cutting is successive; 5) finish machining contrail should surface of clingy spare parts, pliable and smooth, change along acuteness direction. Quality of process designing of cutting of high speed of process designing of cutting of 2 high speed affects the quality of the product directly, process designing wants to notice: 1) reduce program block as far as possible, raise a program to treat rate; 2) use suitable mill commonly, suitable mill can produce less heat in metal cutting, reduce cutting tool load, acquire better exterior quality; 3) the quick inverting of the sharp change that reduces rate and cutting tool, make orbit light suitable; 4) reduce cutting tool cut cut, obtain stable cutting process; 5) reduce milling bear variation, control of use mental allowance is even; 6) machine to 5 axes, the content that treatment of dimensional curved surface involves is more, involve treatment to guide move face of curved surface, interference, contrail to limit the technical content such as knife of area, advance and retreat and control of cutter shaft vector. The key that machines orbit design is controlling vector of cutting tool axis to be in at passing the constant change of dimensional position or make the vector of cutting tool axis and machine tool primitive coordinate department makes a vacuum a certain angle, the side edge that uses milling cutter or treatment of bottom blade cutting will finish. The vector change control of cutting tool axis is like below a few kinds of means commonly (if pursue,1 is shown) . From the point of the vector control means of cutting tool axis, the cutting means that milling of 5 axes numerical control machines is OK will undertake reasonable cutting tool contrail designs a program according to the treatment of real product. The application that 3 much axes process emulation technique and development because when milling of 5 coordinate high speed is machined, cutting tool contrail is more complex, rate of cutting tool motion is very rapid, treatment risk is great, the method that uses conventional test cutting consequently goes when program of test and verify not only efficiency is low, occupy machine and debug time to grow, and the risk that involves in process of itself test and verify is bigger, modify the program very hard by hand at the same time to book a target, the application that because this is right,the treatment of this kind of machine tool has emulation a technology is very crucial. The CNC Machining that VERICUT software is development of American CGTECH company emulates a system, by NC motion of program verification module, machine tool emulates module, optimize module of feature of method module, much axis module, advanced machine tool, substance to compare the module composition such as module and CAD/CAM interface, can emulate all sorts of CNC systems, can emulate a knife already file, can emulate the NC order that CAD/CAM postposition handles again, its are whole emulation process includes program verification, analysis, machine tool to emulate, optimize and model output. If the graph is shown 2 times,be the whole machine tool that exports from model of → of model of cutting of → of VERICUT of → of software of prototype → CAM to emulate technological process. 3.

Compose of emulation environment of 1 machining complex builds a program to be emulated to NC program comes true to machine in VERICUT software, need beforehand the emulation environment that compose builds whole machining complex. The common procedure that its compose establishs is as follows: Machining complex is analysed (library of the semifinished product that system of coordinate of journey of principle of motion of model of system of CNC of machine tool of affirmatory numerical control and function, machine tool configuration and dimension, machine tool, each reference axis, machine tool and place use, cutting tool and clamping apparatus library) → builds model of machine tool geometry (build, change into format of STL of VERICUT software practicable) → builds machine tool file (build model of machine tool sports, namely component tree, add the geometrical model of each component, exact location) → builds user file and control system file (to the machine tool configuration number controls a system) → builds → of cutting tool library to set machine tool parameter (machine tool parameter needs to install, for instance each axis journey, machine tool at 0 o'clock, machine tool reference point, machine tool changes knife dot to wait) → saves all files. If the graph is shown 3 times,be Duan Ling of some whole cabin, material is aluminous forging, spare parts interior has a lot of model the face needs to machine, but interior space is lesser, preventing collision safety to machine is serious content, use Vericut to emulate treatment process accurately, to the collision of generation real time is adjusted, realize safe treatment. The development postposition processing of 4 aftertreatments program is the most important is the knife that makes CAM software the NC program that orbit translate into suits numerical control system to machine, take a knife through reading file, according to form of structure of machine tool campaign and control statement, undertake coordinate motion commutation and statement form are changed. Use talent of correct postposition processing system only the knife the numerical control program that orbit output can have correctly machining for machine tool of system of corresponding numerical control, because this weaves,pattern plate of correct postposition processing system is the premise condition of numerical control process designing and treatment and one of crucial technologies. The main content of the aftertreatment includes the content of 3 respects: Numerical control system controls the output of the instruction: End of head of compensation of the fixed position that basically includes machine tool sort and machine tool configuration, machine tool, interpolation, main shaft, feed, time-out, cooling, cutting tool, fixed loop, program exports the control that waits for a respect; Format changeover: Data type changes processing of as whole as the circle, string to wait: The control that the output format that basically is aimed at numerical control system is like the respect such as character of address of unit, output; Algorithmic processing: The coordinate commutation when basically be being machined in the light of much coordinate, cross speed of quadrantal processing, feed to control. 4.

The 1 development process that is an introductory aftertreatment with UGNX 1) structure of understanding aftertreatment program 2) 5 coordinate machine tool machines Dao Weiwen the treatment of milling of 5 coordinate numerical control in data structure UGNX, knife the structure of the file basically includes key word and digital information. Key word basically includes CIRCLE of interpolation of GOTO of Fedrat of speed of Speed of rotate speed of cutting tool Tool and its parameter Tldata, main shaft, feed, linear interpolation, circular arc, the subprogram is called reach a loop to call Cycle, lubricant reach a program to end End to wait. Knife dot information basically includes cutting tool coordinate to nod X, Y, Z and VectorX of information of vector of cutting tool axis, VectorY, VectorZ. How is the main task of the aftertreatment aimed at a knife namely the data structure information of the file, course geometry commutation, numeric computation and the machine program code that try output of file of solution, code, format to match amount to to accuse machine tool system to identify. 3) postposition of machine tool of 5 coordinate numerical control handles algorithm generally speaking, 5 coordinate linkage is the X that points to numerical control machine tool, Y, Z3 the random in mobile coordinate and the A of 3 rotational coordinate that circle axis of X, Y, Z to rotate, B, C the linear interpolation of 5 coordinate moves, it is the random in X, Y, Z and A of 3 rotational coordinate, B, C normally the 5 coordinate linkage of 2 composition, if the graph shows the coordinate system for 5 coordinate machine tool 4 times. The campaign of rotational coordinate A, B, C can come true by the roll of circumgyrate workbench, OK also by cutting tool swing will come true. Because the athletic way of machine tool of different type numerical control is abhorrent, algorithm of its postposition processing is not consequently identical also. The coordinate of machine tool motion that 5 coordinate machine is cutting tool the coordinate that fastens at coordinate of machine tool motion relatively, is not the coordinate that cutting tool photograph fastens to workpiece coordinate (if pursue,5 are shown) . 4) when undertaking machining on the 4 coordinate that a few issues that want an attention take circumgyrate workbench in application or machine tool of 5 coordinate numerical control, need notes the following problems: The whirligig of workbench of circumgyrate of problem of address of word of ① circumgyrate motion moves word address code and its corner to express by bout have a change of luck, code of this word address is one of A, B, C, U, V, W commonly, but do not concern on behalf of the correspondence with reference axis usually, a of that is to say (or U) do not state circumgyrate workbench circles X axis to rotate certainly, b (or V) do not state circumgyrate workbench circles Y axis to rotate certainly, c (or W) do not state circumgyrate workbench circles Z axis to rotate certainly, and requirement process designing person very clear its motion concerns, so that apply afore-mentioned algorithm to undertake postposition is handled, corner era enters the word address of circumgyrate workbench when output. Still should notice next, general workbench of circumgyrate of machine tool of 4 coordinate numerical control is to serve as the accessory of the machine tool to provide an user, can ask by craft installation is on the workbench of the machine tool (resemble installing dividing head to install the workbench in milling machine to go up euqally) , the runner shaft of such circumgyrate workbench can agree with X axis, can agree with Y axis, also can agree with Z axis, answer when postposition is handled special attention, this problem often is encountered in 4 coordinate CNC Machining. The account that this problem produces problem of ② corner trend is two knives cent belongs to Ι and Π quadrant (inside YZ plane) , the settlement of this problem the jumping-off place of method is corner + 360 ° or - 360 ° , do not affect real position of the job so, and the contrail that makes cutting tool presses a demand moves. Much coordinate CNC Machining two successive knives linear interpolation is between the dot, two knives the differential seat angle between the dot does not allow too big (90 ° of ＜ ＜ ) , otherwise linear interpolation error is very big. The ③ feed dot, dot that retreat a knife and movement of knife of advance and retreat; ④ outputs the processing of event of cutting tool news; Department of ⑤ translation coordinate is handled with runner shaft coming back. 4.

2The development FIDIA KR214 of KR214 aftertreatment program rotates to take the 6 axes of workbench machining center of milling of 5 linkage high speed, type of motion of its machine tool is shown 6 times like the graph, among them C axis depends on for driven for axis of drive shaft, A axis, rotate workbench is W axis. Because show some CAM software not to support the aftertreatment of numerical control program of 6 axes linkage mostly, and in be being machined actually, general 5 axes linkage is enough and contented generated need. What machine in the light of this machine tool is characteristic, can weave according to need X, Y, Z, A, C5 program of axial linkage aftertreatment and the program of 5 axes aftertreatment that include 3 linear axes and A/W. Program of program of these two kinds of aftertreatments can satisfy project requirement, modify the aftertreatment program that suits KR214(or machine tool of K211) numerical control. CNC Milling