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英文資料 High-speed milling High-speed machining is an advanced manufacturing technology, different from the traditional processing methods. The spindle speed, cutting feed rate, cutting a small amount of units within the time of removal of material has increased three to six times. With high efficiency, high precision and high quality surface as the basic characteristics of the automobile industry, aerospace, mold manufacturing and instrumentation industry, such as access to a wide range of applications, has made significant economic benefits, is the contemporary importance of advanced manufacturing technology. For a long time, people die on the processing has been using a grinding or milling EDM (EDM) processing, grinding, polishing methods. Although the high hardness of the EDM machine parts, but the lower the productivity of its application is limited. With the development of high-speed processing technology, used to replace high-speed cutting, grinding and polishing process to die processing has become possible. To shorten the processing cycle, processing and reliable quality assurance, lower processing costs. 1 One of the advantages of high-speed machining High-speed machining as a die-efficient manufacturing, high-quality, low power consumption in an advanced manufacturing technology. In conventional machining in a series of problems has plagued by high-speed machining of the application have been resolved. 1.1 Increase productivity High-speed cutting of the spindle speed, feed rate compared withtraditional machining, in the nature of the leap, the metal removal rate increased 30 percent to 40 percent, cutting force reduced by 30 percent, the cutting tool life increased by 70% . Hardened parts can be processed, a fixture in many parts to be completed rough, semi-finishing and fine, and all other processes, the complex can reach parts of the surface quality requirements, thus increasing the processing productivity and competitiveness of products in the market. 1.2 Improve processing accuracy and surface quality High-speed machines generally have high rigidity and precision, and other characteristics, processing, cutting the depth of small, fast and feed, cutting force low, the workpiece to reduce heat distortion, and high precision machining, surface roughness small. Milling will be no high-speed processing and milling marks the surface so that the parts greatly enhance the quality of the surface. Processing Aluminum when up Ra0.40.6um, pieces of steel processing at up to Ra0.2 0.4um. 1.3 Cutting reduce the heat Because the main axis milling machine high-speed rotation, cutting a shallow cutting, and feed very quickly, and the blade length of the workpiece contacts and contact time is very short, a decrease of blades and parts of the heat conduction. High-speed cutting by dry milling or oil cooked up absolute (mist) lubrication system, to avoid the traditional processing tool in contact with the workpiece and a lot of shortcomings to ensure that the tool is not high temperature under the conditions of work, extended tool life. 1.4 This is conducive to processing thin-walled parts High-speed cutting of small cutting force, a higher degree of stability, Machinable with high-quality employees compared to the company may be very good, but other than the companys employees may Suanbu Le outstanding work performance. For our China practice, we use the models to determine the method of staff training needs are simple and effective. This study models can be an external object, it can also be a combination of internal and external. We must first clear strategy for the development of enterprises. Through the internal and external business environment and organizational resources, such as analysis, the future development of a clear business goals and operational priorities. According to the business development strategy can be compared to find the business models, through a comparative analysis of the finalization of business models. In determining business models, a, is the understanding of its development strategy, or its market share and market growth rate, or the staff of the situation, and so on, according to the companies to determine the actual situation. As enterprises in different period of development, its focus is different, which means that enterprises need to invest the manpower and financial resources the focus is different. So in a certain period of time, enterprises should accurately selected their business models compared with the departments and posts, so more practical significance, because the business models are not always good, but to compare some aspects did not have much practical significance, Furthermore This can more fully concentrate on the business use of limited resources. Identify business models, and then take the enterprise of the corresponding departments and staff with the business models for comparison, the two can be found in the performance gap, a comparative analysis to find reasons, in accordance with this business reality, the final identification of training needs. The cost of training is needed, if not through an effective way to determine whether companies need to train and the training of the way, but blind to training, such training is difficult to achieve the desired results. A comparison only difference between this model is simple and practical training. 1.5 Can be part of some alternative technology, such as EDM, grinding high intensity and high hardness processing High-speed cutting a major feature of high-speed cutting machine has the hardness of HRC60 parts. With the use of coated carbide cutter mold processing, directly to the installation of a hardened tool steel processing forming, effectively avoid the installation of several parts of the fixture error and improve the parts of the geometric location accuracy. In the mold of traditional processing, heat treatment hardening of the workpiece required EDM, high-speed machining replace the traditional method of cutting the processing, manufacturing process possible to omit die in EDM, simplifying the processing technology and investment costs . High-speed milling in the precincts of CNC machine tools, or for processing centre, also in the installation of high-speed spindle on the general machine tools. The latter not only has the processing capacity of general machine tools, but also for high-speed milling, a decrease of investment in equipment, machine tools increased flexibility. Cutting high-speed processing can improve the efficiency, quality improvement, streamline processes, investment and machine tool investment and maintenance costs rise, but comprehensive, can significantly increase economic efficiency. 2 High-speed milling High-speed milling the main technical high-speed cutting technology is cutting the development direction of one of it with CNC technology, microelectronic technology, new materials and new technology, such as technology development to a higher level. High-speed machine tools and high-speed tool to achieve high-speed cutting is the prerequisite and basic conditions, in high-speed machining in the performance of high-speed machine tool material of choice and there are strict requirements. 2.1 High-speed milling machine in order to achieve high-speed machining General use of highly flexible high-speed CNC machine tools, machining centers, and some use a dedicated high-speed milling, drilling. At the same time a high-speed machine tool spindle system and high-speed feeding system, high stiffness of the main characteristics of high-precision targeting and high-precision interpolation functions, especially high-precision arc interpolation function. High-speed machining systems of the machine a higher demand, mainly in the following areas: General use of highly flexible high-speed CNC machine tools, machining centers, and some use a dedicated high-speed milling, drilling. At the same time a high-speed machine tool spindle system and high-speed feeding system, high stiffness of the main characteristics of high-precision targeting and high-precision interpolation functions, especially high-precision arc interpolation function. High-speed machining systems of the machine a higher demand, mainly in the following areas: High-speed milling machine must have a high-speed spindle, the spindle speed is generally 10000 100000 m / min, power greater than 15 kW. But also with rapid speed or in designated spots fast-stopping performance. The main axial space not more than 0 .0 0 0 2 m m. Often using high-speed spindle-hydrostatic bearings, air pressure-bearing, mixed ceramic bearings, magnetic bearing structure of the form. Spindle cooling general use within the water or air cooled. High-speed processing machine-driven system should be able to provide 40 60 m / min of the feed rate, with good acceleration characteristics, can provide 0.4 m/s2 to 10 m/s2 acceleration and deceleration. In order to obtain good processing quality, high-speed cutting machines must have a high enough stiffness. Machine bed material used gray iron, can also add a high-damping base of concrete, to prevent cutting tool chatter affect the quality of processing. A high-speed data transfer rate, can automatically increase slowdown. Processing technology to improve the processing and cutting tool life. At present high-speed machine tool manufacturers, usually in the general machine tools on low speed, the feed of the rough and then proceed to heat treatment, the last in the high-speed machine on the half-finished and finished, in improving the accuracy and efficiency at the same time, as far as possible to reduce processing Cost. 2.2 High-speed machining tool High-speed machining tool is the most active one of the important factors, it has a direct impact on the efficiency of processing, manufacturing costs and product processing and accuracy. Tool in high-speed processing to bear high temperature, high pressure, friction, shock and vibration, such as loading, its hardness and wear-resistance, strength and toughness, heat resistance, technology and economic performance of the basic high-speed processing performance is the key One of the factors. High-speed cutting tool technology development speed, the more applications such as diamond (PCD), cubic boron nitride (CBN), ceramic knives, carbide coating, (C) titanium nitride Carbide TIC (N) And so on. CBN has high hardness, abrasion resistance and the extremely good thermal conductivity, and iron group elements between the great inertia, in 1300 would not have happened significant role in the chemical, also has a good stability. The experiments show that with CBN cutting tool HRC35 67 hardness of hardened steel can achieve very high speed. Ceramics have good wear resistance and thermal chemical stability, its hardness, toughness below the CBN, can be used for processing hardness of HRC 5 0 parts. Carbide Tool good wear resistance, but the hardness than the low-CBN and ceramics. Coating technology used knives, cutting tools can improve hardness and cutting the rate, for cutting HRC40 50 in hardness between the workpiece. Can be used to heat-resistant alloys, titanium alloys, hightemperature alloy, cast iron, Chungang, aluminum and composite materials of high-speed cutting Cut, the most widely used. Precision machining non-ferrous metals or non-metallic materials, or the choice of polycrystalline diamond Gang-coated tool. 2.3 High-speed processing technology High-speed cutting technology for high-speed machining is the key. Cutting Methods misconduct, will increase wear tool to less than high-speed processing purposes. Only high-speed machine tool and not a good guide technology, high-speed machining equipment can not fully play its role. In high-speed machining, should be chosen with milling, when the milling cutter involvement with the workpiece chip thickness as the greatest, and then gradually decreased. High-speed machining suitable for shallow depth of cut, cutting depth of not more than 0.2 mm, to avoid the location of deviation tool to ensure that the geometric precision machining parts. Ensure that the workpiece on the cutting constant load, to get good processing quality. Cutting a single high-speed milling path-cutting mode, try not to interrupt the process and cutting tool path, reducing the involvement tool to cut the number to be relatively stable cutting process. Tool to reduce the rapid change to, in other words when the NC machine tools must cease immediately, or Jiangsu, and then implement the next step. As the machine tool acceleration restrictions, easy to cause a waste of time, and exigency stop or radical move would damage the surface accuracy. In the mold of high-speed finishing, in each Cut, cut to the workpiece, the feed should try to change the direction of a curve or arc adapter, avoid a straight line adapter to maintain the smooth process of cutting. 3 Die in high-speed milling processing of Milling as a highly efficient high-speed cutting of the new method,in Mould Manufacturing has been widely used. Forging links in the regular production model, with EDM cavity to be 12 15 h, electrodes produced 2 h. Milling after the switch to high-speed, high-speed milling cutter on the hardness of HRC 6 0 hardened tool steel processing. The forging die processing only 3 h20min, improve work efficiency four to five times the processing surface roughness of Ra0.5 0.6m, fully in line with quality requirements. High-speed cutting technology is cutting technology one of the major developments, mainly used in automobile industry and die industry, particularly in the processing complex surface, the workpiece itself or knives rigid requirements of the higher processing areas, is a range of advanced processing technology The integration, high efficiency and high quality for the people respected. It not only involves high-speed processing technology, but also including high-speed processing machine tools, numerical control system, high-speed cutting tools and CAD / CAM technology. Die-processing technology has been developed in the mold of the manufacturing sector in general, and in my application and the application of the standards have yet to be improved, because of its traditional processing with unparalleled advantages, the future will continue to be an inevitable development of processing technology Direction. 4 Numerical control technology and equipping development trend and countermeasure Equip the engineering level, level of determining the whole national economy of the modernized degree and modernized degree of industry, numerical control technology is it develop new developing new high-tech industry and most advanced industry to equip (such as information technology and his industry, biotechnology and his industry, aviation, spaceflight, etc. national defense industry) last technology and getting more basic most equipment. Marx has ever said the differences of different economic times, do not lie in what is produced, and lie in how to produce, produce with some means of labor . Manufacturing technology and equipping the most basic means of production that are that the mankind produced the activity, and numerical control technology is nowadays advanced manufacturing technology and equips the most central technology. Nowadays the manufacturing industry all around the world adopts numerical control technology extensively, in order to improve manufacturing capacity and level, improve the adaptive capacity and competitive power to the changeable market of the trends. In addition every industrially developed country in the world also classifies the technology and numerical control equipment of numerical control as the strategic materials of the country, not merely take the great measure to develop ones own numerical control technology and industry, and implement blockading and restrictive policy to our country in view of high-grade, precision and advanced key technology of numerical control and equipping. In a word, develop the advanced manufacturing technology taking numerical control technology as the core and already become every world developed country and accelerate economic development in a more cost-effective manner, important way to improve the overall national strength and national position. Numerical control technology is the technology controlled to mechanical movement and working course with digital information, integrated products of electromechanics that the numerical control equipment is the new technology represented by numerical control technology forms to the manufacture industry of the tradition and infiltration of the new developing manufacturing industry, namely the so-called digitization is equipped, its technological range covers a lot of fields: (1)Mechanical manufacturing technology; (2)Information processing, processing, transmission technology; (3)Automatic control technology; (4)Servo drive technology; (5)Technology of the sensor; (6)Software engineering ,etc. Development trend of a numerical control technology The application of numerical control technology has not only brought the revolutionary change to manufacturing industry of the tradition, make the manufacturing industry become the industrialized symbol , and with the constant development of numerical control technology and enlargement of the application, the development of some important trades (IT , automobile , light industry , medical treatment ,etc. ) to the national economy and the peoples livelihood of his plays a more and more important role, because the digitization that these trades needed to equip has already been the main trend of modern development. Numerical control technology in the world at present and equipping the development trend to see, there is the following several respect 1- in its main research focus. 5 A high-speed, high finish machining technology and new trend equipped The efficiency, quality are subjavanufacturing technology. High-speed, high finish machining technology can raise the efficiency greatly , improve the quality and grade of the products, shorten production cycle and improve the market competitive power. Japan carries the technological research association first to classify it as one of the 5 great modern manufacturing technologies for this, learn (CIRP) to confirm it as the centre in the 21st century and study one of the directions in international production engineering. In the field of car industry, produce one second when beat such as production of 300,000 / vehicle per year, and many variety process it is car that equip key problem that must be solved one of; In the fields of aviation and aerospace industry, spare parts of its processing are mostly the thin wall and thin muscle, rigidity is very bad, the material is aluminium or aluminium alloy, only in a situation that cut the speed and cut strength very small high, could process these muscles, walls. Adopt large-scale whole aluminium alloy method that blank pay empty make the wing recently, such large-scale parts as the fuselage ,etc. come to substitute a lot of parts to assemble through numerous rivet , screw and other connection way, make the intensity , rigidity and dependability of the component improved. All these, to processing and equipping the demand which has proposed high-speed, high precise and high flexibility. According to EMO2001 exhibition situation, high-speed machining center is it give speed can reach 80m/min is even high , air transport competent speed can up to 100m/min to be about to enter. A lot of automobile factories in the world at present, including Shanghai General Motors Corporation of our country, have already adopted and substituted and made the lathe up with the production line part that the high-speed machining center makes up. HyperMach lathe of U.S.A. CINCINNATI Company enters to nearly biggest 60m/min of speed, it is 100m/min to be fast, the acceleration reaches 2g, the rotational speed of the main shaft has already reached 60 000r/min. Processing a thin wall of plane parts, spend 30min only, and same part general at a high speed milling machine process and take 3h, the ordinary milling machine is being processed to need 8h; The speed and acceleration of main shaft of dual main shaft lathes of Germany DMG Company are up to 120000r/mm and 1g. In machining accuracy, the past 10 years, ordinary progression accuse of machining accuracy of lathe bring 5m up to from 10m already, accurate grades of machining center from 3 5m, rise to 1 1.5m, and ultraprecision machining accuracy is it enter nanometer grade to begin already (0.01m). In dependability, MTBF value of the foreign numerical control device has already reached above 6 000h, MTBF value of the servo system reaches above 30000h, demonstrate very high dependability . In order to realize high-speed, high finish machining, if the part of function related to it is electric main shaft, straight line electrical machinery get fast development, the application is expanded further . 5.2 Link and process and compound to process the fast development of the lathe in 5 axes Adopt 5 axles to link the processing of the three-dimensional curved surface part, can cut with the best geometry form of the cutter , not only highly polished, but also efficiency improves by a large margin . It is generally acknowledged, the efficiency of an 5 axle gear beds can equal 2 3 axle gear beds, is it wait for to use the cubic nitrogen boron the milling cutter of ultra hard material is milled and pared at a high speed while quenching the hard steel part, 5 axles link and process 3 constant axles to link and process and give play to higher benefit. Because such reasons as complicated that 5 axles link the numerical control system , host computer structure that but go over, it is several times higher that its price links the numerical control lathe than 3 axles , in addition the technological degree of difficulty of programming is relatively great, have restricted the development of 5 axle gear beds. At present because of electric appearance of main shaft, is it realize 5 axle complex main shaft hair structure processed to link greatly simplify to make, it makes degree of difficulty and reducing by a large margin of the cost, the price disparity of the numerical control system shrinks. So promoted 5 axle gear beds of head of complex main shaft and compound to process the development of the lathe (process the lathe including 5). At EMO2001 exhibition, new Japanese 5 of worker machine process lathe adopt complex main shaft hair, can realize the processing of 4 vertical planes and processing of the wanton angle, make 5 times process and 5 axles are processed and can be realized on the same lathe, can also realize the inclined plane and pour the processing of the hole of awls. Germany DMG Company exhibits the DMUVoution series machining center, but put and insert and put processing and 5 axles 5 times to link and process in once, can be controlled by CNC system or CAD/CAM is controlled directly or indirectly. 5.3 Become the main trend of systematic development of contemporary numerical control intelligently, openly, networkedly. The numerical control equipment in the 21st century will be sure the intelligent system, the intelligent content includes all respects in the numerical control system: It is intelligent in order to pursue the efficiency of processing and process quality, control such as the self-adaptation of the processing course, the craft parameter is produced automatically; Join the convenient one in order to improve the performance of urging and use intelligently, if feedforward control , adaptive operation , electrical machinery of parameter , discern load select models , since exactly makes etc. automatically; The ones that simplified programming , simplified operating aspect are intelligent, for instance intelligent automatic programming , intelligent man-machine interface ,etc.; There are content of intelligence diagnose , intelligent monitoring , diagnosis convenient to be systematic and maintaining ,etc. Produce the existing problem for the industrialization of solving the traditional numerical control system sealing and numerical control application software. A lot of countries carry on research to the open numerical control system at present, such as NGC of U.S.A. (The Next Generation Work-Station/Machine Control), OSACA of European Community (Open System Architecture for Control within Automation Systems), OSEC (Open System Environment for Controller) of Japan, ONC (Open Numerical Control System) of China, etc. The numerical control system melts to become the future way of the numerical control system open. The so-called open numerical control system is the development of the numerical control system can be on unified operation platform, face the lathe producer and end user, through changing, increasing or cutting out the structure target(numerical control function), form the serration, and can use users specially conveniently and the technical know-how is integrated in the control system, realize the open numerical control system of different variety , different grade fast, form leading brand products with distinct distinction. System structure norm of the open numerical control system at present, communication norm , disposing norm , operation platform , numerical control systematic function storehouse and numerical control systematic function software development ,etc. are the core of present research. The networked numerical control equipment is a new light spot of the fair of the internationally famous lathe in the past two years. Meeting production line , manufacture system , demand for the information integration of manufacturing company networkedly greatly of numerical control equipment, realize new manufacture mode such as quick make , fictitious enterprise , basic Entrance that the whole world make too. Some domestic and international famous numerical control lathes and systematic manufacturing companies of numerical control have all introduced relevant new concepts and protons of a machine in the past two years, if in EMO2001 exhibition, Cyber Production Center that the company exhibits of mountain rugged campstool gram in Japan (Mazak) (intellectual central production control unit, abbreviated as CPC); The lathe company of Japanese big Wei (Okuma ) exhibits IT plaza (the information technology square , is abbreviated as IT square ); Open Manufacturing Environment that the company exhibits of German Siemens (Siemens ) (open the manufacturing environment, abbreviated as OME),etc., have reflected numerical control machine tooling to the development trend of networked direction. 5.4 Pay attention to the new technical standard, normal setting-up 5.4.1 Design the norm of developing about the numerical control system As noted previously, there are better common ability, flexibility, adaptability, expanding in the open numerical control system, such countries as U.S.A. ,European Community and Japan ,etc. implement the strategic development plan one after another , carry on the research and formulation of the systematic norm (OMAC , OSACA , OSEC ) of numerical control of the open system structure, 3 biggest economies in the world have carried on the formulation that nearly the same science planned and standardized in a short time, have indicated a new arrival of period of change of numerical control technology. Our country started the research and formulation of standardizing the frame of ONC numerical control system of China too in 2000. 5.4.2 About the numerical control standard The numerical control standard is a kind of trend of information-based development of manufacturing industry. Information exchange among 50 years after numerical control technology was born was all because of ISO6983 standard, namely adopt G, M code describes how processes, its essential characteristic faces the processing course, obviously, he cant meet high-speed development of modern numerical control technologys needs more and more already. For this reason, studying and making a kind of new CNC system standard ISO14649 (STEP-NC) in the world, its purpose is to offer a kind of neutral mechanism not depending on the concrete system, can describe the unified data model in cycle of whole life of the products, thus realize the whole manufacture process, standardization of and even each industrial field product information. The appearance of STEP-NC may be a revolution of the technological field of the numerical control, on the development and even the whole manufacturing industry of numerical control technology, will exert a far-reaching influence. First of all, STEP-NC puts forward a kind of brand-new manufacture idea, in the traditional manufacture idea, NC processes the procedures to all concentrate on individual computer. Under the new standard, NC procedure can be dispersed on Internet, this is exactly a direction of open , networked development of numerical control technology. Secondly, STEP-NC numerical control system can also reduce and process the drawing (about 75%), process the procedure to work out the time (about 35%) and process the time (about 50%) greatly. At present, American-European countries pay much attention to the research of STEP-NC, Europe initiates IMS plan (1999.1.1-2001.12.3) of STEP-NC. 20 CAD/CAM/CAPP/CNC users, manufacturers and academic organizations from Europe and Japan participated in this plan. STEP Tools Company of U.S.A. is a developer of the data interchange software of manufacturing industry in the global range, he has already developed the super model (Super Model ) which accuses of information exchange of machine tooling by counting, its goal is to describe all processing courses with the unified norm. Such new data interchange form has already been verified in allocating the SIEMENS, FIDIA and European OSACA-NC numerical control at present. 6 pairs of basic estimations of technology and industry development of numerical control of our country The technology of numerical control of our country started in 1958, the development course in the past 50 years can roughly be divided into 3 stages: The first stage is from 1958 to 1979, namely closed developing stage. In this stages, because technology of foreign countries blockade and basic restriction of terms of our country, the development of numerical control technology is comparatively slow. During Sixth Five-Year Plan Period , the Seventh Five-Year Plan Period of the country in second stage and earlier stage in the Eighth Five-Year Plan Period , namely introduce technology, digest and assimilate, the stage of establishing the system of production domesticization arisesing tentatively. At this stage , because of reform and opening-up and national attention , and study the improvement of the development environment and international environment, research , development and all making considerable progress in production domesticization of the products of the technology of numerical control of our country. The third stage is and during the Ninth Five-Year Plan Period on the later stage in the Eighth Five-Year Plan Period of the country, namely implement the research of industrialization, enter market competition stage. At this stage, made substantive progress in industrialization of the domestic numerical control equipment of our country. In latter stage for the Ninth Five-Year Plan , the domestic occupation rate of market of the domestic numerical control lathe is up to 50%, it is up to 10% too to mix the domestic numerical control system (popular). Make a general survey of the development course in the past 50 years of technology of numerical control of our country, especially through tackling key problems of 4 Five-Year Plans, all in all has made following achievements. a. Have established the foundation of the technical development of numerical control, has mastered modern numerical control technology basically. Our country has already, the numerical control host computer, basic technology of special plane and fittings grasped and driven from the numerical control system and survey basically now, among them most technology have already possessed and commercialized the foundation developed, some technology has already, industrialization commercialized. b. Have formed the industrial base of numerical control tentatively. In tackling key problems the foundation that the achievement and some technology commercialize, set up the systematic factories of numerical control with production capacity in batches such as numerical control in Central China, numerical control of the spaceflight etc. Electrical machinery plant of Lanzhou, such factory and the first machine tool plant of Beijing , the first machine tool plant of Jinan ,etc. several numerical control host computer factories of a batch of servo systems and servo electrical machineries as the numerical control in Central China, etc. These factories have formed the numerical control industrial base of our country basically. c. Have set up a numerical control research, development, managerial talents basic team. Though has made considerable progress in research and development and industrialization of numerical control technology, but we will realize soberly, the research and development of the technology of advanced numerical control of our country, especially there is greater disparity in current situation and current demand of our country of engineering level in industrializatio n. Though very fast from watching the development of our country vertically, have disparity horizontally more than (compare foreign countries with) not merely engineering level, there is disparity too in development speed in some aspects, namely the engineering level disparity between some high-grade , precision and advanced numerical control equipment has the tendency to expand . Watch from world, estimate roughly as follows about the engineering level of numerical control of our country and industrialization level. a. On the engineering level, in probably backward 10-1 years with the advanced level in foreign countries, it is bigger in high-quality precision and sophisticated technology. b. On the industrialization level, the occupation rate of market is low, the variety coverage rate is little, have not formed the large-scale production yet; The specialized level of production of function part and ability of forming a complete set are relatively low; Appearance quality is relatively poor; Dependability is not high, the commercialized degree is insufficient; Ones own brand effect that the domestic numerical control system has not been set up yet, users have insufficient confidence. c. On the ability of sustainable development, research and development of numerical control technology, project ability is relatively weak to the competition; It is not strong that the technological application of numerical control expands dynamics; Research, formulation that relevant standards are normal lag behind. It is analyzed that the main reason for having above-mentioned disparity has the following several respect. a. Realize the respect. Know to industrys process arduousness , complexity and long-term characteristic of domestic numerical control insufficiently; It is difficult to underestimate to add strangling, system, etc. to the unstandard, foreign blockade of the market; It is not enough to analyse to the technological application level and ability of numerical control of our country. b. System. Pay close attention to numerical control industrialization many in the issue, consider numerical control industrialization little in the issue synthetically in terms of the systematic one, industry chain in terms of technology; Have not set up related system, perfect training , service network of intact high quality ,etc. and supported the system. c. Mechanism. It causes the brain drain, restraining technology and technological route from innovating again, products innovation that the bad machine is made, and has restricted the effective implementation of planning, has often planned the ideal, implement the difficulty. d. Technology. The autonomous innovation in technology of enterprises is indifferent; the project of key technology is indifferent. The standard of the lathe lags behind, the level is relatively low, it is not enough for new standard of the numerical control system to study. 7 pairs of strategic thinking of technology and industrialized development of numerical control of our country 7.1 Strategic consideration Our country make big country, industry is it is it accept front instead of transformation of back end to try ones best to want in shifting in world, namely should master and make key technology advanced, otherwise in a new round of international industrial structure adjustment, the manufacturing industry of our country will step forward and leave the core spaces . We regard resource, environment , market as the cost, it is only an international machining center in the new economic pattern of the world to exchange the possibility got and assemble the centre , but not master the position of the manufacturing center of key technology , will so influence the development process of the modern manufacturing industry of our country seriously. We should stand in the height of national security strategy paying attention to numerical control technology and industrys question , at first seen from social safety, because manufacturing industry whether our country obtain employment most populous trade, the development of manufacturing industry not only can improve the peoples living standard but also can alleviate the pressure of employment of our country , ensure the stability of the society; Secondly seen from national defense security, the western developed country has classified all the high-grade , precision and advanced numerical control products as the strategic materials of the country, realizing the embargo and restriction to our country, Toshiba incident and Cox Report is the best illustration. 7.2 Development tactics Proceed from the angles of the fundamental realities of the country of our country, regard the strategic demand of the country and market demand of national economy as the direction, regard improving our country and making the comprehensive competitive power of equipping industry and industrialization level as the goal, use the systematic method , be able to choose to make key technology upgraded in development of equipping industry and support technology supporting the development of industrialization in our country in initial stage of 21st century in leading factor, the ability to supply the necessary technology realizes making the jump development of the equipping industry as the content of research and development . Emphasize market demand is a direction, namely take terminal products of numerical control as the core, with the complete machine (Such as the numerical control lathe having a large capacity and a wide range, milling machine, high speed high precise high-performance numerical control lathe, digitized machinery of model, key industry key equipment, etc.) drive the development of the numerical control industry. Solve the numerical control system and relevant functions part especially The dependability that (digitized servo system and electrical machinery, high speed electric main shaft system and new-enclosure that equip, etc.) and production scale question. There are no products that scale will not have high dependability; Will not have cheap and products rich in the competitiveness without scale; Certainly, it is difficult to have day holding up ones head finally that there is no scale Chinese numerical control equipment. In equiping researching and developing high-grade , precision and advancedly , should emphasize the production, learning and research and close combination of the end user, regard drawing, using, selling as the goal, tackle key problems according to the national will, in order to solve the needing badly of the country. Numerical control technology, emphasized innovation, put emphasis on researching and developing the technology and products with independent intellectual property right before the competition, establish the foundation for the industry of numerical control of our country, sustainable development of equipment manufacture and even the whole manufacturing industry. 英文翻譯對(duì)照 高速銑削 高速切削加工是一種先進(jìn)制造技術(shù),不同于傳統(tǒng)加工方式。它的主軸轉(zhuǎn)速高、切削進(jìn)給速度高、切削量小,單位時(shí)間內(nèi)的材料切除量卻增加 3 6 倍。它以高效率、高精度和高表面質(zhì)量為基本特征,在汽車工業(yè)、航空航天、模具制造和儀器儀表等行業(yè)中獲得了廣泛的應(yīng)用,取得了重大的經(jīng)濟(jì)效益,是當(dāng)代先進(jìn)制造技術(shù)的重要應(yīng)用。長期以來,人們對(duì)模具的加工一直采用銑削一磨削或者電火花 (EDM)加工、打磨、拋光的方法。雖然電火花可加工硬度很高的工件,但較低的生產(chǎn)率使它的應(yīng)用受到制。隨著高速加工技術(shù)的發(fā)展,采用高速切削取代磨 削拋光和電加工進(jìn)行模具加工已成為可能。使加工周期大為縮短,加工質(zhì)量得到可靠保證,加工成本降低。 1 高速切削加工的優(yōu)勢(shì) 高速切削加工作為模具制造中集高效、優(yōu)質(zhì)、低耗于一身的先進(jìn)制造技術(shù)。在常規(guī)切削加工中備受困擾的一系列問題,通過高速切削加工的應(yīng)用得到了解決。 1.1 提高生產(chǎn)率 高速切削的主軸轉(zhuǎn)速、進(jìn)給速度與傳統(tǒng)切削加工相比,發(fā)生了本質(zhì)性的飛躍,其金屬切除率提高了 30%40%,切削力降低了 30%,刀具的切削壽命提高了 70%。還可加工淬硬零件,許多零件一次裝夾可完成粗、半精和精加工等全部工序,對(duì)復(fù)雜型面也能 達(dá)到零件表面質(zhì)量要求,進(jìn)而提高了加工生產(chǎn)率和產(chǎn)品的市場(chǎng)競(jìng)爭(zhēng)力。 1.2 改善加工精度和表面質(zhì)量 高速機(jī)床普遍具備高剛性和高精度等特點(diǎn),加工時(shí)切削深度小,而進(jìn)給速度較快,切削力低,工件熱變形減少,而加工精度很高,表面粗糙度很小。高速銑削可獲得無銑痕的加工表面,使零件表面質(zhì)量大大提高。加工鋁合金時(shí)可達(dá) Ra0.40.6um,加工鋼件時(shí)可達(dá) Ra0.20.4um。 1.3 減少切削產(chǎn)生的熱量 因?yàn)殂姶仓鬏S高速旋轉(zhuǎn),切削加工是淺切削,同時(shí)進(jìn)給速度很快,刀刃和工件的接觸長度和接觸時(shí)間非常短,減少了刀刃和工件的熱傳導(dǎo)。高 速切削采用干銑或油一氣 (油霧 )潤滑系統(tǒng),避免了傳統(tǒng)加工時(shí)在刀具和工件接觸處產(chǎn)生大量熱的缺點(diǎn),保證刀具在溫度不高的條件下工作,延長了刀具的使用壽命。 1.4 有利于加工薄壁零件 高速切削時(shí)的切削力小,有較高的穩(wěn)定性,可加工高質(zhì)量同本公司內(nèi)部員工相比可能是非常優(yōu)秀的,但是同其他的公司的員工相比工作績(jī)效可能算不了優(yōu)秀。就我們中國實(shí)際來說,我們使用標(biāo)桿分析法來確定員工培訓(xùn)需求是簡(jiǎn)單有效的。這種學(xué)習(xí)標(biāo)桿對(duì)象可以是外部的,也可以是內(nèi)部和外部的結(jié)合。首先要明確企業(yè)的發(fā)展戰(zhàn)略。通過對(duì)企業(yè)內(nèi)外部環(huán)境和組織資 源等分析,明確企業(yè) 未來發(fā)展的目標(biāo)和業(yè)務(wù)重點(diǎn)。根據(jù)企業(yè)的發(fā)展戰(zhàn)略尋找可以比照的標(biāo)桿企業(yè),通過比較分析,最后確定標(biāo)桿企業(yè)。在確定標(biāo)桿企業(yè)后,有一項(xiàng),是了解其發(fā)展戰(zhàn)略,還是其市場(chǎng)占有率和市場(chǎng)增長率,還是員工各方面的情況等等,這要根據(jù)本企業(yè)的實(shí)際情況來確定。由于企業(yè)在不同的發(fā)展時(shí)期,其著力點(diǎn)是不同的,即企業(yè)需要投入的物力人力財(cái)力的重點(diǎn)是不同的。所以在一定的時(shí)期內(nèi),企業(yè)要準(zhǔn)確地選定其跟標(biāo)桿企業(yè)比較的部門和崗位,這樣更加具有實(shí)際意義,因?yàn)闃?biāo)桿企業(yè)并不是處處都好,而且有些方面進(jìn)行比較沒有多少實(shí)際意義,再者這樣可以更充分地集中利用企業(yè)的有限 資源。確定標(biāo)桿企業(yè)后,然后拿本企業(yè)的相應(yīng)的部門和員工同標(biāo)桿企業(yè)進(jìn)行比較,可以發(fā)現(xiàn)兩者在工作績(jī)效的差距,比較分析,尋找原因,根據(jù)本企業(yè)的實(shí)際,最后確定培訓(xùn)需求。培訓(xùn)是需要成本的,如果沒有通過有效的方式,去確定企業(yè)是否需要培訓(xùn)以及培訓(xùn)的方式,而是盲目進(jìn)行培訓(xùn),這樣的培訓(xùn)是難以取得預(yù)期的效果。有比較才有區(qū)別,這種培訓(xùn)分析模型簡(jiǎn)單實(shí)用。 1.5 可部分替代某些工藝,如電火花加工、磨削加工 高速切削的一大特點(diǎn),高速切削已可加工硬度達(dá) HRC60 的零件。采用帶涂層的硬質(zhì)合金刀具加工模具,直接將淬硬工具鋼一次安裝加工成形 ,有效地避免了零件多次安裝造成的裝夾誤差,提高了零件的幾何位置精度。在傳統(tǒng)加工模具的工藝中,對(duì)熱處理硬化后的工件需進(jìn)行電火花加工,用高速切削加工替代傳統(tǒng)切削的加工方法,可以省去模具制造工藝中的電火花加工,簡(jiǎn)化了加工工藝和投資成本。 高速銑削加工可在專用的 CNC 機(jī)床或加工中心上進(jìn)行,也可在加裝高速主軸的普通機(jī)床上進(jìn)行。后者不僅具有普通機(jī)床的加工能力,而且還可進(jìn)行高速銑削,減少了設(shè)備投資,增加了機(jī)床柔性。高速切削可以使加工效率提高、質(zhì)量提高、工序簡(jiǎn)化,機(jī)床投資和刀具投資及維護(hù)費(fèi)用上升,但綜合比較,可以顯著提高 經(jīng)濟(jì)效益。 2 高速銑削加工 高速銑削加工的主要技術(shù) 高速切削技術(shù)是切削加工技術(shù)的發(fā)展方向之一,它隨著 C N C 技術(shù)、微電子技術(shù)、新材料和新工藝等技術(shù)的發(fā)展而邁上更高的臺(tái)階。高速機(jī)床和高速刀具是實(shí)現(xiàn)高速切削的前提和基本條件,在高速切削加工中對(duì)高速機(jī)床的性能和刀具材料的選擇有嚴(yán)格的要求。 2.1 高速銑削加工機(jī)床 為了實(shí)現(xiàn)高速切削加工 一般采用高柔性的高速數(shù)控機(jī)床、加工中心,也有的采用專用的高速銑、鉆床。機(jī)床同時(shí)具有高速主軸系統(tǒng)和高速進(jìn)給系統(tǒng),高的主軸剛度特性,高精度定位功能和高精度插補(bǔ)功能,特別是圓弧高精度插 補(bǔ)功能。高速切削加工對(duì)機(jī)床的工藝系統(tǒng)提出了更高的要求,主要表現(xiàn)在以下幾個(gè)方面: 高速銑削機(jī)床必須具有高速主軸,主軸的轉(zhuǎn)速 10000100000m/min,功率大于 15kW。還應(yīng)具有快速升速、在指定位置快速準(zhǔn)停的性能。主軸的軸向間隙不大于 0 .0 0 0 2 m m 。高速主軸常采用液體靜壓軸承式、空氣靜壓軸承式、混合陶瓷軸承、磁懸浮軸承式等結(jié)構(gòu)形式。主軸冷卻一般采用內(nèi)部水冷或氣冷。 高速加工機(jī)床的驅(qū)動(dòng)系統(tǒng)應(yīng)能夠提供 40 60m/min 的進(jìn)給速度,具有良好的加速度特 性,能夠提供 0.4m/s2 到 10m/s2的加速度和減速度。為了獲得良好的加工質(zhì)量,高速切削機(jī)床必須具有足夠高的剛度。機(jī)床床身材料采用灰鑄鐵,還可以在底座中添加高阻尼特性的混凝土,以防止切削時(shí)刀具顫振影響加工質(zhì)量。具有高速數(shù)據(jù)傳輸率,能夠自動(dòng)加減速。加工工藝有利于切削加工和提高刀具壽命。目前高速機(jī)床的廠家,通常在普通機(jī)床上進(jìn)行低速、大進(jìn)給的粗加工,然后進(jìn)行熱處理,最后在高速機(jī)床上進(jìn)行半精加工和精加工,在提高精度和效率的同時(shí)盡可能地降低加工成本。 2.2 高速切削加工刀具 刀具是高速切削加工中最活躍重要的因素之一,它直接影響著加工效率、制造成本和產(chǎn)品的加工精度。刀具在高速加工過程中要承受高溫、高壓、摩擦、沖擊和振動(dòng)等載荷,因此其硬度和耐磨性、強(qiáng)度和韌性、耐熱性、工藝性能和經(jīng)濟(jì)性等基本性能是實(shí)現(xiàn)高速加工的關(guān)鍵因素之一。高速切削加工的刀具技術(shù)發(fā)展速度很快,應(yīng)用較多的如金剛石 (P C D)、立方氮化硼 (C B N))、陶瓷刀具、涂層硬質(zhì)合金、 (碳 )氮化鈦硬質(zhì)合金 T I C (N)等。立方氮化硼具有很高的硬度、極強(qiáng)的耐磨性和良好的導(dǎo)熱性,與鐵族元素之間有很大的惰性,在 1300也不會(huì)發(fā)生顯著的化學(xué)作用,還具有良好的穩(wěn)定性。實(shí)驗(yàn)表明,用 CBN 刀具切削硬度 HRC3567 的淬火鋼可以達(dá)到很高速度。陶瓷材料具有良好的耐磨性和熱化學(xué)穩(wěn)定性,其硬度、韌性低于 C B N ,可用于加工硬度 H R C 5 0 的零件。硬質(zhì)合金刀具耐磨性好,但硬度比立方氮化硼和陶瓷低。采用刀具涂層技術(shù),可以提高刀具硬度和切削加工的速度,適合切削硬度在 HRC40 50 之間的工件??捎糜谀蜔岷辖?、鈦合金、高溫合金、鑄鐵、純鋼、鋁合金及復(fù)合材料的高速切削,應(yīng)用最為廣泛。精密加工有色金屬或非金屬材料時(shí),選用聚晶金剛石或金剛石涂層刀具。 2.3 高速加工工藝 高速切削的工藝技術(shù)也是進(jìn)行高速切削 加工的關(guān)鍵。切削方法選擇不當(dāng),會(huì)使刀具加劇磨損,達(dá)不到高速加工的目的。只有高速機(jī)床和刀具沒有好的工藝技術(shù)指導(dǎo),高速切削加工設(shè)備也不能充分發(fā)揮作用。在高速切削加工中,應(yīng)盡量選用順銑加工,順銑時(shí)刀具切入工件的切屑厚度為最大,隨后逐漸減小。高速切削加工適于淺的切深,切削深度不超過 0.2mm,可避免刀具的位置偏差,確保加工零件的幾何精度。保證工件上的切削載荷恒定,以獲得好的加工質(zhì)量。高速切削采用單一路徑順銑切削模式,盡量不中斷切削過程和刀具路徑,減少刀具的切入切出次數(shù),以獲得相對(duì)穩(wěn)定的切削過程。減少刀具的急速換向, 在換向時(shí) NC機(jī)床必須立即停止或降速,再執(zhí)行下一步操作。由于機(jī)床的加速度限制,易造成時(shí)間浪費(fèi),而且急?;蚣眲?dòng)會(huì)破壞表面精度。在模具的高速精加工中,在每次切入、切出工件時(shí),進(jìn)給方向的改變應(yīng)盡量采用圓弧或曲線轉(zhuǎn)接,避免采用直線轉(zhuǎn)接,以保持切削過程的平穩(wěn)性。 3 高速銑削在模具加工中的應(yīng)用 高速銑削作為高效切削加工的新方法,在模具制造中得到了廣泛應(yīng)用。在常規(guī)生產(chǎn)連桿鍛模時(shí),用電火花加工型腔需 12 15h,電極制作 2h。改用高速銑削后,采用高速立銑刀對(duì)硬度 H R C 6 0 的淬硬工具鋼進(jìn)行加工。整個(gè)鍛模加工只需 3h20min,工效提高 4 5 倍,加工表面粗糙度達(dá) Ra0.5 0.6m ,質(zhì)量完全符合要求。 高速切削技術(shù)是切削加工技術(shù)的主要發(fā)展方向之一,目前主要應(yīng)用于汽車工業(yè)和模具行業(yè),尤其是在加工復(fù)雜曲面、工件本身或刀具剛性要求較高的加工領(lǐng)域等,是多種先進(jìn)加工技術(shù)的集成,其高效、高質(zhì)量為人們所推崇。它不僅涉及到高速加工工藝,而且還包括高速加工機(jī)床、數(shù)控系統(tǒng)、高速切削刀具及 C A D / C A M 技術(shù)等。模具高速加工技術(shù)目前已在發(fā)達(dá)國家的模具制造業(yè)中普遍應(yīng)用,而在我國的應(yīng)用范圍及應(yīng)用水平仍有待提高,由于其具有傳統(tǒng)加工 無可比擬的優(yōu)勢(shì),仍將是今后加工技術(shù)必然的發(fā)展方向。 4 數(shù)控技術(shù)和裝備發(fā)展趨勢(shì)及對(duì)策 裝備工業(yè)的技術(shù)水平和現(xiàn)代化程度決定著整個(gè)國民經(jīng)濟(jì)的水平和現(xiàn)代化程度,數(shù)控技術(shù)及裝備是發(fā)展新興高新技術(shù)產(chǎn)業(yè)和尖端工業(yè)(如信息技術(shù)及其產(chǎn)業(yè)、生物技術(shù)及其產(chǎn)業(yè)、航空、航天等國防工業(yè)產(chǎn)業(yè))的使能技術(shù)和最基本的裝備。馬克思曾經(jīng)說過 “ 各種經(jīng)濟(jì)時(shí)代的區(qū)別,不在于生產(chǎn)什么,而在于怎樣生產(chǎn),用什么勞動(dòng)資料生產(chǎn) ” 。制造技術(shù)和裝備就是人類生產(chǎn)活動(dòng)的最基本的生產(chǎn)資料,而數(shù)控技術(shù)又是當(dāng)今先進(jìn)制造技術(shù)和裝備最為核心的技術(shù)。當(dāng)今世界各國制造業(yè)廣泛采用數(shù) 控技術(shù),以提高制造能力和水平,提高對(duì)動(dòng)態(tài)多變市場(chǎng)的適應(yīng)能力和競(jìng)爭(zhēng)能力。此外,世界上各工業(yè)發(fā)達(dá)國家還將數(shù)控技術(shù)及數(shù)控裝備列為國家的戰(zhàn)略物資,不僅采取重大措施來發(fā)展自己的數(shù)控技術(shù)及其產(chǎn)業(yè),而且在 “ 高精尖 ” 數(shù)控關(guān)鍵技術(shù)和裝備方面對(duì)我國實(shí)行封鎖和限制政策??傊?,大力發(fā)展以數(shù)控技術(shù)為核心的先進(jìn)制造技術(shù)已成為世界各發(fā)達(dá)國家加速經(jīng)濟(jì)發(fā)展、提高綜合國力和國家地位的重要途徑。 數(shù)控技術(shù)是用數(shù)字信息對(duì)機(jī)械運(yùn)動(dòng)和工作過程進(jìn)行控制的技術(shù),數(shù)控裝備是以數(shù)控技術(shù)為代表的新技術(shù)對(duì)傳統(tǒng)制造產(chǎn)業(yè)和新興制造業(yè)的滲透形成的機(jī)電一體化產(chǎn)品,即所謂 的數(shù)字化裝備,其技術(shù)范圍覆蓋很多領(lǐng)域: (1)機(jī)械制造技術(shù); (2)信息處理、加工、傳輸技術(shù); (3)自動(dòng)控制技術(shù); (4)伺服驅(qū)動(dòng)技術(shù); (5)傳感器技術(shù); (6)軟件技術(shù)等。 5 數(shù)控技術(shù)的發(fā)展趨勢(shì) 數(shù)控技術(shù)的應(yīng)用不但給傳統(tǒng)制造業(yè)帶來了革命性的變化,使制造業(yè)成為工業(yè)化的象征,而且隨著數(shù)控技術(shù)的不斷發(fā)展和應(yīng)用領(lǐng)域的擴(kuò)大,他對(duì)國計(jì)民生的一些重要行業(yè)( IT、汽車、輕工、醫(yī)療等)的發(fā)展起著越來越重要的作用,因?yàn)檫@些行業(yè)所需裝備的數(shù)字化已是現(xiàn)代發(fā)展的大趨勢(shì)。從目前世界上數(shù)控 技術(shù)及其裝備發(fā)展的趨勢(shì)來看,其主要研究熱點(diǎn)有以下幾個(gè)方面 1 4。 5.1 高速、高精加工技術(shù)及裝備的新趨勢(shì) 效率、質(zhì)量是先進(jìn)制造技術(shù)的主體。高速、高精加工技術(shù)可極大地提高效率,提高產(chǎn)品的質(zhì)量和檔次,縮短生產(chǎn)周期和提高市場(chǎng)競(jìng)爭(zhēng)能力。為此日本先端技術(shù)研究會(huì)將其列為 5 大現(xiàn)代制造技術(shù)之一,國際生產(chǎn)工程學(xué)會(huì)( CIRP)將其確定為 21 世紀(jì)的中心研究方向之一。 在轎車工業(yè)領(lǐng)域,年產(chǎn) 30 萬輛的生產(chǎn)節(jié)拍是 40 秒 /輛,而且多品種加工是轎車裝備必須解決的重點(diǎn)問題之一;在航空和宇航工業(yè)領(lǐng)域,其加工的零部件多為薄壁和薄筋,剛度很 差,材料為鋁或鋁合金,只有在高切削速度和切削力很小的情況下,才能對(duì)這些筋、壁進(jìn)行加工。近來采用大型整體鋁合金坯料 “ 掏空 ” 的方法來制造機(jī)翼、機(jī)身等大型零件來替代多個(gè)零件通過眾多的鉚釘、螺釘和其他聯(lián)結(jié)方式拼裝,使構(gòu)件的強(qiáng)度、剛度和可靠性得到提高。這些都對(duì)加工裝備提出了高速、高精和高柔性的要求。 從 EMO2001 展會(huì)情況來看,高速加工中心進(jìn)給速度可達(dá) 80m/min,甚至更高,空運(yùn)行速度可達(dá) 100m/min 左右。目前世界上許多汽車廠,包括我國的上海通用汽車公司,已經(jīng)采用以高速加工中心組成的生產(chǎn)線部分替代組合機(jī)床。美 國 CINCINNATI 公司的 HyperMach 機(jī)床進(jìn)給速度最大達(dá) 60m/min,快速為 100m/min,加速度達(dá) 2g,主軸轉(zhuǎn)速已達(dá) 60 000r/min。加工一個(gè)薄壁飛機(jī)零件,只用 30min,而同樣的零件在一般高速銑床加工需 3h,在普通銑床加工需8h;德國 DMG 公司的雙主軸車床的主軸速度及加速度分別達(dá) 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