Crucial technology of 5 axes CNC Machining is discussed

Time:2023-06-14 11:08:48
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source:KOMANG CNC Machining

The article introduced the definition that 5 axes machine, characteristic, classification; Linkage of the 3+2 in describing 5 axes CNC Machining, 4+1, 5 axes machines the characteristic of mode and size range of pipe bent 3 kinds; Emphasize the crucial technology that introduced 5 axes treatment, include software of CAD/CAM of craft of 5 axes equipment, treatment, 5 axes, this 3 person the core technology that is 5 axes treatment, be short of one cannot. 1 overview is well-known, numerical control machine tool is the main production facility of current and modern chemical plant, numerical control technology is advanced the crucial technology of production technology, conventional treatment is being replaced stage by stage by CNC Machining, level of CNC Machining technology already made report a country is advanced one of main index of production technology. Machining center of 5 axes linkage represented the top level of numerical control machine tool, reflected the development level of the equipment manufacturing industry of a country. The numerical control equipment of our country passes development of more than 60 years, in make multinomial technology obtain very great progress, but in equipment of high-end CNC Machining production respect foundation still compares weakness, software platform and database are machined to develop a respect to still lag behind at world advanced level in much axis linkage, want farther promotion. Application of 5 axes CNC Machining is very wide, of the core part that basically uses in the high-end product such as water and electricity of aerospace, irrigation works, ship make, the dynamo rotor in equipment of water and electricity of large whole impeller, irrigation works makes the aviation engine that has structure of complex curved surface for example, the turbine in car engine and mould are made wait for a domain. These spare partses are the core component of relevant product, affect the function of the product and quality directly. In western equipment manufacturing industry relatively the country that develop, manufacture efficiency to rise, machining center of 5 axes linkage already got applied extensively in each domain of manufacturing industry. Nowadays, as contemporary product quality rise, ask reductive of spare parts amount begs spare parts precision even at the same time rise, this makes the complex abnormity of structural unifinication the demand of the spare parts is bigger and bigger, its delivery time is shorter and shorter, of the treatment advantage in view of machining center of 5 axes linkage and price of machining center of 5 axes linkage reduce, machining center of 5 axes linkage will make each domain get be popularizinged extensively in treatment. Accordingly, begin 5 axes the research of processing technique special be necessary and the sense is great. CNC Machining of 2 5 axes is so called 5 axes CNC Machining is the CNC Machining that points to the linkage that can dominate 5 above reference axis at the same time, include 3 straight bobbin among them (XYZ) and two runner shaft coming back (ABC3 two in runner shaft coming back) . After 5 axes treatment combines all sorts of treatment functions together, after realizing workpiece to hold clip in, finish the mill to many, boring, get the treatment that waits for much talk working procedure, avoided effectively for many times to install the error that places generation, shortened production is periodic, improve spare parts quality. As the structure the wide application of complex product, equipment of demand numerical control has higher process capability and treatment efficiency, from this, technology of 5 axes CNC Machining got wide development field. The characteristic of 5 axes CNC Machining has: Cutting tool can be entered model antrum is in-house, machine 3 axes to machine the place that be less than, the sidewall that this kind of mode is helpful for using short cutting tool to machine a spare parts and model antrum, raise the tigidity of cutting tool, reduce vibration, raise the precision of the spare parts; Reduce tool clamping apparatus amount and cover an area of an area; Reduce fiducial changeover, raise treatment precision; Shorten new product research and development is periodic; Shorten manufacturing process catenary, simplify manufacturing management. 5 axes are machined according to linkage number of axle different, can divide for " 3+2 " , " 4+1 " , 5 axes linkage machines 3 kinds of mode. 2.

1 " 3+2 " the axis machines mode " 3+2 " the commonly used mode that treatment is 5 axes treatment, what it points to is to be in process of 5 axes treatment, in two runner shaft coming back (two in ABC) after vector way is certain, 3 straight bobbin (the way that XYZ) makes 3 axes combine motion to finish a spare parts to machine. Mode of this kind of treatment can improve manufacturing efficiency, reduce the number that hold clip, avoid the mounting error of the spare parts. When mode of this kind of treatment is machining the bottom of spare parts of casing, mould or sidewall, can use snickersnee to provide treatment to raise treatment tigidity. Undertaking " 3+2 " when 5 axes machine mode, want to build fixed position coordinate to fasten first, the fixed position that the part is having after the runner shaft coming back that decides a machine tool next is machined, kong Shi is machined on oblique plane, use pattern of this kind of treatment, body reveals very tall efficiency. "3+2 " the process designing of 5 axes treatment of mode is relatively simple, to 5 axes machine tool wear away small (the service life of runner shaft coming back is lower than linear service life) . "3+2 " the inadequacy of 5 axes treatment of mode is: Existence machines bounds between two vector when treatment, in precision the meeting when be being machined on not tall 5 axes machine tool arises " step " , and treatment of 5 axes linkage can avoid. 2.

2 " 4+1 " the axis machines mode " 4+1 " what axial treatment points to is: When undertaking 5 axes are machined, a runner shaft coming back (one of ABC axis) angle is affirmatory, 3 when remain straight bobbin add axis of a whirligig to be able to do associated motion to complete the treatment of the spare parts at the same time. Mode of treatment of this kind of 5 axes suits to machine approximate swing tower kind spare parts. Use below the circumstance that makes sure cutting tool is hands-off use " 4+1 " axial treatment can reduce a spare parts to hold clip number, improve manufacturing efficiency, raise the treatment precision of the spare parts. 2.

Linkage of 3 5 axes machines treatment of 5 axes linkage to point to 5 movement rod (include XYZ_ two in linear axis and ABC runner shaft coming back) a kind of pattern that at the same time motion has machining to the spare parts. When undertaking 5 axes linkage is machined, can be opposite the direction of cutting tool axes in machining a process undertakes optimizing, change the vector way of cutter shaft, assure to go up to be able to maintain the most efficient cutting pattern in method of whole cutting tool, have successional, without the trace receiving a knife of treatment, exterior surface roughness is good wait for an advantage. Treatment of 5 axes linkage can control machining error not only, and can improve quality of spare parts surface, can ask according to craft at the same time, even ground excises material of complex curved surface, the stress that can control workpiece effectively so and heat change. The whole that machining engine of airscrew, aviation for example needs to use 5 axes linkage to machine the quality that assures a product and precision when impeller. If the graph shows 1 times,above machines mode 3 kinds: Graph the 5 axes part that the crucial technique that 3 5 axes process mode of treatment of 1 5 axes wants to machine a high quality needs to have advanced 5 axes equipment, efficient 5 axes process designing software and reasonable 5 axes treatment craft, 3 person be short of one cannot. Particular operation flow is: The basis machines a condition, finish the three-dimensional model of the spare parts and cutter track setting with CAD/CAM software, according to postposition of machine tool function processing creates numerical control program; Apply emulation software to undertake owing cutting next, cut too, collision detects and try cutting; Operate 5 axes machine tool to complete the treatment of the spare parts finally. 3.

Machine tool of 1 5 axes machine tool of 5 axes numerical control charges a machine tool at 3 number of axle relatively for, it is the question that raises two runner shaft coming back not just, it is having very big promotion on technology of algorithmic, control, its key technology incorporates technology of main shaft speed, drive and control technology, these parameter affected the size range of pipe bent of machine tool of 5 axes numerical control and treatment precision. 3.

Speed of 1 main shaft. Machine tool of 5 axes numerical control is in complex abnormity when, often need to use small diameter cutting tool to improve quality of spare parts surface, for this need main shaft has higher rotate speed. The main shaft of 5 axes machine tool uses electric main shaft mostly nowadays (main shaft speed maintains basically will improve efficiency in 20000 ～ 50000r/min) , reduce energy loss. In subtle milling (milling cutter diameter is used commonly 0.

1 ～ 2mm) in machining a process, need machine tool has higher main shaft rotate speed. 3.

2 drive technology. When undertaking complex curved surface is machined, the main shaft rotate speed that often needs pair of 5 axes machine tools and angle have apply the brake and speed change in order to suit all sorts of model the treatment of the face. Be in to achieve higher feed rate or go up in the method taking a knife of stone's throw, machine the outline of the spare parts smoothly, this has very tall main shaft acceleration with respect to requirement equipment. Accordingly, in process of 5 axes treatment, the acceleration of main shaft machines those who controlling a part the life of precision and cutting tool. Current, common machining center is main it is to use servo electric machinery and ball guide screw to come drive is steep the axis moves, but already began to use linear electric machinery now to equipment of high-end numerical control, the DMC75VLinear high speed that is like German DMU company 5 axes machining center. The advantage of linear electric machinery includes: Can simplify machine tool structure, motion of circumgyrate of lieutenant general of subtractive machine tool changes the mechanical drive disk assembly that is sharp movement, reduce energy loss, raise a spare parts effectively to machine precision thereby, assure the stability of the dynamic function of each axis and mobile linear velocity. Nowadays, the campaign that machining center of major 5 axes linkage uses torsion electric machinery basically to control main shaft head and circumgyrate workbench and swing. Torsion electric machinery is a kind of synchronous electric machinery, belong to orgnaization of direct actuating device, it secures the component that has need drive on rotor, can reduce mechanical drive component as far as possible so. The servo of torsion electric machinery answers delicacy, output torque is big, without transmission clearance, without the contact between the spare parts transmission (avoid wear and tear) wait for a characteristic, its angular velocity is the 6 times above of orgnaization of worm of traditional worm wheel, the acceleration that swings in head of drive main shaft can amount to 3g above. The mechanical drive structure that uses torsion electric machinery to replace a tradition can simplify equipment, reduce component amount, improve transmission efficiency, increase the stability that whole orgnaization runs at the same time, improve the treatment quality of the spare parts and efficiency thereby. 3.

3 control technology. While treatment of 5 axes linkage should realize 5 movement rod namely, move, the treatment of the spare parts that finish. As a result of the existence of whirligig axis, bringing about coordinate to fasten is athletic change, make the algorithm that process designing algorithm compares 3 axes machine tool a lot of more complex, all sorts of interpolation operation amounts are huge, at the same time subtle whirl reference axis error will cause very big machining error. For this, ask system of numerical control of machining center of 5 axes linkage has powerful control and servo ability and efficient operation speed and control precision, still ask the system has good cutter shaft center to control administrative ability at the same time, realize compensation of cutting tool length and compensation of cutting tool radius, realize cylinder thereby face and tilt the efficient treatment of working surface. It is at present in treatment of 5 axes linkage, commonly used numerical control system has: The ITNC530 of the Siemens840D of German Siemens company and Heidenhain company, they apply extensively in the numerical control equipment of all sorts of high end. Nextpage3.

2 5 axes machine craft of craft of 5 axes CNC Machining differentiate mode has: Press thick, finish machining cent, wait for an element according to the appearance of the spare parts, dimension and precision, thick precision work apart principle undertakes craft differentiates; Center cent by cutting tool, differentiate by what the cutting tool of the choice has technology, can reduce the number that change a knife, shorten handling time, improve treatment precision and efficiency; By treatment place is divided, the principle that follow has first close hind far, first brief hind numerous, first the aperture after plane. When finish machining of 5 axes linkage, ability of the tigidity of 5 axes equipment, cutting and by the hardness of cutting material it is the factor that should consider. According to machining procedure, general when 5 axes finish machining obligate 0.

5 ～ 0.

The surplus finish machining of 8mm. Too large cutting amount is unallowed, it will cause damage to the main shaft of 5 axes machine tool, when accordingly technologist is making craft plan, answering to consider the cutting parameter when 5 axes linkage is machined again, written inform operation personnel note. Making should undertake emulation test and verify before treatment of 5 axes linkage at the same time, avoid collision and the generation that cut a phenomenon too. 3.

3 5 axes machine crucial technology 3.

1 cutter shaft is controlled. The cutting tool contrail in process of treatment of 5 axes linkage is very complex with abstraction, give the curved surface of complex different component and space for treatment, often need to undertake the change of coordinate department and cutter shaft will complete the treatment of the spare parts for many times, consider the harmonious sex of each movement rod even at the same time, avoid the generation of phenomenon of interference, collision, because this is carrying out Cheng,the need before foreword uses CAD/CAM software to undertake test and verify to cutter shaft. 3.

2 try cut treatment. In process of treatment of 5 axes linkage, what assure to process a system to raise the efficiency that much axis machines to reach is rigid, the cost that actual cutting parameter often wants to compare the set in NC program is low (move fold inferior cost first as far as possible, rise slowly next, till find an optimal program) ; Additional, it is when the 5 motion reference axis of 5 axes equipment when motion, its tigidity wants than 3 axes equipment low, if processing is bad, machine what affect the function of equipment and product directly precision. 3.

3CAD/CAM software. Want to realize the 5 axes treatment of complex curved surface, the key needs software of 5 axes CAD/CAM to implement treatment technology. The software that can undertake 5 axes process designing nowadays has NX, HyperMILL, Cimatron, Powermill, Caxa to make an engineer wait, have a function as a result of Powermill software among them powerful, the operation is handy wait for a characteristic, in home market have rate rising in year after year. More and more schools, factory is weaving with Powermill software 5 axes machine cutter track now, complete the treatment of complex abnormity spare parts. The 5 axes treatment in Powermill software is a lot of more politic, among them " curved surface is umbriferous finish machining " politic size range of pipe bent mass of wide, generated cutting tool method is efficient, special the treatment that applies to complex curved surface, more and more get the favour of mechanical workmanship division. For this, consider " curved surface is umbriferous finish machining " the meaning of principle, relevant parameter and use method, good to using sense of strategy of treatment of this 5 axes is great. 3.

4 cutter track are optimized. When program of work out NC, should avoid cutter shaft needless, exceeding swings, those who because machine tool main shaft or workbench are too frequent,prevent swing, cause the damage of the machine tool. When undertaking cutter track is optimized, emphasize the setting that should note join cutter track, after building much axis cutter track, still require a basis feature of machine tool function, spare parts, adjust parameter of join cutter track, optimize cutting tool method. 3.

5 emulation test and verify. Because 5 axes equipment is precious, machine program amount is large, question of the interference that needs a consideration, collision is more, before be being machined actually so, must undertake imitate is machined first. The CAM software nowadays can undertake the test and verify of the program basically only, emulate the effective treatment circumstances such as actual craft tool very hard, before undertaking actual 5 axes linkage is machined so, the much axis numerical control that suggests process designing personnel uses major emulates software (VERICUT) undertakes emulation machining, come the security of craft of test and verify and program, dependability, enhance the safe safeguard of handlers and machine tool at the same time. 4 epilogue the definition that the article introduced 5 axes to machine, characteristic, classification; Emphasize the crucial technology that introduced 5 axes CNC Machining, include software of CAD/CAM of craft of 5 axes equipment, treatment, 5 axes. This is answered when undertaking much axis is machined 3 person have thorough research, find out optimal program, choose optimal parameter, ability realizes the efficient, high quality of 5 axes to machine. Current, CNC Machining forward high speed, efficient way develops, use 5 axes CNC Machining, can simplify craft tool, because manipulate the error effect to product precision,reduce, shortened greatly cutting handling time acquires better treatment surface quality. Produce the periodic, competition ability that reduces the labour cost, treatment precision that raises a part and enterprise to shorten, more and more make kind of enterprise use 5 axes treatment to replace original treatment mode. Author: Cao writes Ming Jiwen dragon CNC Milling CNC Machining