1 Introduction In recent years, with the rapid development of China's economy, the demand for automobiles has continued to grow, and the automobile and auto parts manufacturing industry has become the largest and most important user in the gold Cutting Machine tool and tool industry. The engine is the heart of the car, and its parts manufacturing process is generally higher than other car parts. Advanced tools such as coated tools, ceramic tools, and superhard tools are widely used in engine manufacturing processes. Most of China's automobile production lines (especially car production lines) are imported from abroad. At the time of production, imported tools are mainly used on the production line, and the cutting amount of tools is also recommended by foreign countries. These tools combine advanced technologies such as new materials, new processes, cutting principles, surface treatments, etc., with high performance, high life and high reliability, which basically represent the advanced level of modern cutting tool technology. Since China's tool manufacturing enterprises have long been mainly oriented to the manufacturing industries such as trucks and tractors, the level of tool technology is relatively low compared to the car manufacturing industry. Therefore, it is very important for domestic tool manufacturers to participate in the competition between domestic and international markets and to improve the overall technical level of the company. 2 China's automobile engine manufacturing technology development trend and tool application status 2.1 Automobile engine manufacturing technology development trend Domestic new production of automobile engine production line has three obvious trends in manufacturing technology: (1) High-speed realization of high-speed cutting processing basic requirements Yes: 1 use machine tool spindles that can achieve high-speed operation; 2 use high-precision, high-rigidity HSK tool holders with strong chucks; 3 use advanced tools such as coated carbide, cermet, ceramics, CBN, PCD. (2) Flexibility Flexibility is one of the development trends of engine manufacturing. A production line that uses a CNC or a machining center to realize flexible processing at a local station of a conventional automatic line is called a flexible automatic line (FTL), and is generally used in a Japanese factory. A flexible manufacturing system consisting of a dedicated machining center is mainly used for cylinder head and cylinder processing. From the perspective of production, it can reach an annual output of 50,000 pieces from the traditional FMS system to 200,000 pieces of traditional automatic line production. (3) High efficiency From the perspective of the Japanese automobile manufacturing industry, the cutting efficiency is increased by 28% every five years, and the cutting speed is increased by an average of 19%, and the feed rate is increased by 8% on average, and the cutting efficiency has increased in recent years. More than 30%. At present, the production cycle of the main parts of the engine has been shortened to 30 to 40 seconds, which is more than 50% shorter than a decade ago. For example, a cylinder of gray cast iron material is milled by a high-speed machining center, and the cutting speed can reach V=700-1500 m/min, and the cutter adopts a CBN insert. When milling aluminum alloy cylinders and cylinder heads, PCD tools are widely used. Considering the high centrifugal force generated during high-speed rotation, the cutter body is made of high-strength aluminum alloy material. In short, an obvious trend in the engine manufacturing industry is to use high-speed machining technology to improve efficiency, shorten delivery time, reduce production costs, and improve market competitiveness. 2.2 Current status of tool application The automobile industry is the industry with the most application of special tools, and it is also a measure of the technical level of a country or a tool company. Most of China's automobile production lines (especially car production lines) are imported from abroad, and the tools are mainly imported with the equipment. At present, the domestic automobile production lines are American type, European type, Japanese and Korean type, and autonomous type mainly based on European equipment. In this way, the mainstream of the five major tool factions is active in China: First, the mountain specialties (including Seco), Sandvik has a large and complex tool branch, which has the largest sales volume in the Chinese market; the second is the American department, mainly Kenner and English. Gesell, Wannite, etc. are the representatives; the third is the European Department, mainly in Germany, including MAPAL, Guehring, Widia, TITEX, Walter, etc.; Fourth, Japan and South Korea, including Mitsubishi, Sumitomo, Toshiba, OSG, Yu Jie , Fujitsu, Hitachi, etc., as well as Taegutec and KORLOY in South Korea; the fifth is the Israeli department, mainly ISCAR. These companies almost fill the market space for automotive tools. In some large automobile manufacturers, domestically produced tools may only account for about 10% of the total project. Therefore, imported tools still occupy a dominant position. 2.3 The main problems existing in the country The overall state of the domestic tool industry is low starting point and late start. Advanced CNC tools are only developed and produced with the development of CNC machine tools in recent years. Therefore, the basics of CNC tool products are relatively weak and the development speed is slow. Competitiveness is not strong. The main reason why foreign tool industry can grab the Chinese market is: foreign tool products are of high grade, full variety, good quality; and the tools are closely related to the machine tool, foreign machine tools often use tools that have been used abroad; The types of domestically produced tools are incomplete, and most of the foreign tools are used in product finishing, high-performance cutting and special requirements. The combined effect of many factors has formed the passive situation of domestically produced tools. There are many obstacles in the process of localization of tools, and there are congenital systemic obstacles. Taking the car production line as an example, in the initial stage of introducing the car model and the CNC automatic production line, China often does not pay attention to the domestic matching problem of the tool, and does not timely improve the technical level of the domestic car cutter. After the introduction of the production line, the number of special tools and tools that come with it is numerous, and the requirements of process technology and specialization are very high. The varieties, quality, supply and service capabilities of the existing domestic tools are difficult to meet the requirements. At the same time, dozens of foreign tool brands that are well-equipped and ready-to-use have made the localization of tools difficult, and they are obviously in a passive state. 3 Domestic tool manufacturers' participation in international competition Since the 1980s, cutting technology and tools have gradually entered a new stage of high-speed, high-efficiency and innovative processes, driven by the development of the world's manufacturing industry and technological advancement. The processing efficiency has doubled, making an important contribution to the development of the manufacturing industry. Efficient cutting processes and tools have become the basic process and key technology in the automotive industry. New cutting processes such as high-speed cutting, dry cutting, and hard cutting are changing the traditional processing technology and showing great vitality. The author believes that the most fundamental way for domestic tool manufacturers to participate in international competition is to improve the overall tool technology level of the company. Specifically, we must work hard in the following three aspects. 3.1 Accelerate the development of new tool technology (1) Comprehensively improve the performance of various tool materials based on hard alloys In the development of modern tool materials, cemented carbide plays a leading role. In addition, the performance of other tool materials has been significantly improved, expanding their respective application areas, forming a whole pattern of various tool materials with unique advantages, scope of use and complement each other. It is the comprehensive and rapid development of tool materials that lays the foundation for today's high-speed, high-efficiency metal cutting. The performance of cemented carbide is continuously improved, and the application surface is expanding, becoming the main tool material for cutting, which plays an important role in promoting the improvement of cutting efficiency. First of all, the development of fine-grained, ultrafine-grained cemented carbide materials has significantly improved the strength and toughness of cemented carbide materials, and the solid carbide tools produced by it (especially the large and medium-sized general-purpose cutters such as drill bits) , end mills, taps, etc.) a large number of replacement of traditional high-speed steel tools, so that the cutting speed and processing efficiency are greatly improved, the general-purpose tools with a large amount of wide-area are brought into the field of high-speed cutting. Secondly, the development and application of new processes such as cemented carbide pressure sintering improve the intrinsic quality of cemented carbide, and the development of special grades for different processing needs further improves the performance of cemented carbide. Developed a graded hard alloy with good resistance to plastic deformation and toughness. As a base material for chemically coated cemented carbide inserts, it improves the cutting performance and application range of coated carbide inserts. The variety of ceramic and cermet cutting tool materials is increased, the strength and toughness are improved, the application field and processing range are continuously expanded, and the hard alloy can be replaced in the finishing and semi-finishing of steel and cast iron, which improves the processing efficiency and product quality. At present, such tool materials can be used not only in single-piece and small-batch production, but also in mass production of pipelines. Because of the low price, they can be used as the preferred tool for dry cutting and hard cutting. The improvement of PCD and CBN super-hard tool materials and the improvement of manufacturing process have enabled the application field to expand. Cylinder boring tools made of CBN have been used in the production of automatic production lines and cast iron and quenching hardware, and have expanded from the field of finishing to semi-finishing, which has greatly improved the cutting efficiency. Aluminum alloy is an important material widely used in the automotive industry, and efficient processing of aluminum alloy is a key technology. At present, due to the wide application of various high-performance PCD tools, the cutting efficiency is significantly improved, and the highest cutting speed has reached 7000m/min. Products have been expanded from turning tools and face milling cutters to end mills, drill bits, reamers, forming tools and more. (2) Coating as a key technology to improve tool performance Tool coating technology has made significant progress in recent years, and surface coating has become a key technology to improve tool performance. Chemical vapor deposition (CVD) is still the main coating process for indexable inserts. New processes such as medium temperature CVD, thick film Al2O3, and transition layer have been developed to improve the wear resistance of CVD coatings based on the improvement of matrix properties. Both sex and toughness have been significantly improved. CVD diamond coatings have also made great progress, improving the surface finish of the coating and entering a practical stage. At present, the coating ratio of foreign carbide indexable inserts has reached more than 70%. During this period, the progress of physical vapor deposition (PVD) coating technology is particularly striking, and new progress has been made in coating furnace structure, process, automatic control technology, etc., not only for high-speed cutting, dry cutting Hard-cut high-heat-resistance coatings (such as Super TiAlN) and TiAlCN general-purpose coatings with better overall performance and DLC, W/C anti-friction coatings, and through the innovation of coating structure, developed nano-multiple The layer structure coating greatly improves the hardness and toughness of the coating. New advances in PVD coating technology show the great potential and unique advantages of coating technology for improving tool performance. Through the control of coating process parameters and the adjustment of target and reaction gases, new high-performance coatings can be continuously developed. Layers to meet the needs of processing diversity. Coating technology will be a shortcut to improve and improve tool performance, and has a very broad application prospect. (3) Constantly innovating tool structure With the rapid development of the manufacturing industry, key industries such as the automobile industry, aerospace industry, and mold industry are constantly placing higher demands on cutting processing, and promoting the sustainable development of indexable tools. The special set of tools developed for the automobile assembly line has broken through the traditional practice of supplying tools on demand and “closed door makingâ€, and has become an important process factor for innovating the processing technology, improving the processing efficiency and reducing the processing cost, and plays an important role. The agile manufacturing of the automotive industry has become a powerful driving force for the innovation of indexable tool structures, and has promoted the emergence of high-efficiency machining tools such as multi-function face milling cutters, various modular end mill systems, and large feed milling cutters. In order to meet the needs of high-efficiency processing of aluminum alloy components, advanced tools such as aluminum alloy high-speed machining face milling cutters with novel structure have been developed. With the perfection and popularization of the five-axis linkage CNC tool grinding machine, the geometric parameters of the universal cutters such as end mills and drill bits are further diversified, and the traditional pattern of standard tool parameters is changed, which can adapt to different materials to be processed. And the processing conditions, the cutting performance is also improved accordingly. Some innovative tool configurations can also produce new cutting results. For example, unequal helix angle end mills can effectively suppress tool vibrations, improve machine surface finish, and increase tool depth and depth compared to standard end mills. Speed ​​of development; development of carbide taps and carbide thread milling cutters to increase threading efficiency to high-speed cutting levels, especially for carbide thread milling cutters, which not only have high machining efficiency, but also have good versatility, which can significantly reduce the tool cost. 3.2 Emphasis on supporting technology and tool management The cutting technology (including the connection method between the tool holder and the machine tool spindle, the clamping method of the tool in the tool holder, the balance of the tool system and the tool management, etc.) is the progress of the cutting technology. Gradually developed, it is an indispensable part of modern cutting technology, and it keeps pace with cutting technology and cutting tools, constantly changing the connotation of cutting technology and promoting the advancement of cutting technology. With the development of cutting technology, the tool industry is undergoing a revolution in operating mechanisms. In the face of increasingly new production models and new workpiece materials, tools are no longer a simple product that can be “sold outâ€, but an important technological factor in optimizing the processing or production line processing technology. Tool manufacturers must be able to provide users with complete processing technology to help users achieve the goal of improving processing efficiency and product quality, reducing manufacturing costs, which has become the direction and business purpose of foreign tool manufacturers business development. At present, tool manufacturers bring the tool industry to a higher stage of development through various forms of business services such as “serving users†and “providing solutionsâ€. Facts have proved that this practice of foreign tool manufacturers is conducive to the continuous improvement of the overall level of manufacturing, bringing greater economic benefits to users, and will certainly be welcomed by users. The development direction of Tool Management is the general contracting of tools. All the tools of a factory (shop) are outsourced to a company for overall management, to meet the needs of various processing tools, and provide comprehensive procurement, inventory management, including tools. Complete sets of services such as grinding, cleaning adjustment and distribution. According to the information provided by Walter, the cost of the tool only accounts for about 3% of the total processing cost, but it will affect the production efficiency by 20% to 30%. Therefore, in order to effectively reduce the processing cost, the tool cost should be increased appropriately. , using efficient tools to enhance tool management. This is very important to improve the competitiveness of production companies. The concept of tool management first appeared in the United States, and its core is to achieve the following objectives through tool outsourcing: 1 reduce initial investment (tool regrind business can be outsourced or undertaken by tool management suppliers); 2 reduce inventory funds (tool inventory funds from tools) Manage the supplier's commitment); 3 reduce management costs, enabling companies to focus on their core business. Tool management was promoted in the US and Europe from the late 1990s to the beginning of this century. As the tool suppliers in the European and American markets are relatively mature and the operation is relatively standardized, tool management has gradually been recognized by users. For users in the United States or Germany, there are a large number of mature tool manufacturers in the local factory, users can get very timely service, which undoubtedly provides great convenience for the development of tool management business. In China, the development of tool management seems to be somewhat sluggish, and it is only beginning to be applied first in the automotive industry. As the current high-end tool market in China still uses imported tools as the main body, it will create obstacles to tool management in terms of tool supply, information transmission, production cycle, customs declaration and transportation. The resulting shutdown will be the bottom line that users can bear. In addition, there is a concern that it is currently impossible to rule out, that is, users are more likely to rely on tool management suppliers. If another new tool management supplier is selected in the next round of selection, there will inevitably be confusion during the handover. This is mainly due to the fact that the users who are managing the tools are not mature enough, and the number of tool management suppliers available in the Chinese market is still too small. 3.3 Starting from the basics, solving the key tools for processing typical parts (1) Roughing of the crankshaft Due to the particularity of the crankshaft structure of the engine, the current domestic car crankshaft production line is mostly a flexible transfer line (FTL). It is characterized by not only processing the same series of crankshafts, but also processing variants, replacement products and new products. The metal working process of the crankshaft is: milling end face, fixed total length, drill quality center hole, car size end outer circle → milling spindle neck and shoulder shoulder → milling connecting rod neck and shoulder shoulder → car pull spindle neck and sinking groove → car pull Connecting rod neck and sinking groove → gun drilling oil hole → cleaning → fillet rolling → flange drilling tapping → fine grinding spindle neck (CBN) → fine grinding rod neck (CBN) → oblique cutting small end → oblique Cutting the flange end → car rolling thrust surface, milling key groove → dynamic balance → abrasive belt polishing spindle, connecting rod and flange outer diameter → cleaning, cooling → detection classification. For the case where the side of the crankshaft balance block needs to be machined, the CNC neck milling or CNC high-speed outer milling should be preferred for the spindle neck machining, and the CNC high-speed outer milling is used for the processing of the connecting rod neck. If the blank is a forged steel blank, CNC internal milling is more conducive to chip breaking. It is not advisable to use CNC car-car pull. Since the side of the balance block is intermittently turned, the crankshaft speed is very high (about 1000r/m), so the phenomenon of chipping will be quite serious. For the case where the side of the crankshaft balance block does not need to be processed, the spindle neck processing is more reasonable with the CNC car-car pull, and higher machining precision can be obtained. Since the rod neck axis is not on a center line (such as the six-cranked crankshaft), there is some trouble in using the car-car drawing process, and it is more reasonable to use CNC high-speed outer milling. For the machining of crankshafts with undercuts, the CNC-car pull process is superior. If there is an undercut in the axial direction, CNC high-speed external milling and CNC internal milling cannot be processed, and the car-car pull can be processed. For the above processing methods, independent double-cutter, modular tool system, etc. should be used to achieve flexible processing. (2) Indexable face milling cutters In the modern automobile manufacturing industry, the application of face milling is extremely common. In order to meet the needs of the automotive industry, tool manufacturers have also introduced milling cutters and inserts for milling cast iron and other materials. These tools and inserts have greatly improved machining efficiency and surface quality of parts. The use of high-hardness, high-strength tool materials and proper coating is the primary measure to extend tool life. At the same time, improving tool geometry is also an important means of increasing tool life, especially for the milling of cast iron. Milling of cast iron is an important issue in the automotive industry. Various alloy cast irons, including gray cast iron, ductile iron and compacted graphite cast iron, have different processing characteristics. For example, gray cast iron contains a network of hard structures, which is characterized by large brittleness, which is prone to chipping during machining; ductile iron and creep The cast iron has certain plasticity and can produce iron filings, but the workpiece will also produce “flanging†when the cutter is cut out, which may easily lead to damage of the cutting edge. Therefore, it is very important to optimize the geometrical angle of the milling cutter. For example, conventional cast iron milling cutters have negative axial and radial rake angles (double negative angle milling cutters), and this negative geometric angle makes the cutting edge relatively strong. In contrast, the positive and negative angle milling cutters (positive axial rake angle, negative radial rake angle) are smoother to cut, reducing the power requirements of the machine tool and making it easier to use advanced tool materials. (3) Hole processing tools In the hole processing, high-speed steel twist drills are still widely used, but the gap between the processing precision and processing efficiency of various enterprises has gradually widened. The material of the high-speed cutting bit is mainly made of ceramic-coated cemented carbide. For example, MAZAK and Mori Seiki manufacture ceramic cast bits. When processing non-ferrous materials such as aluminum alloys, diamond-coated carbide drills, DLC coated carbide drills or drill bits with diamond sintered body teeth may be used. Among various coated drill bits, ceramic coated carbide drills pay special attention to wear resistance, heat resistance and lubricity. The coating process also adopts multi-layer coating methods, such as using TiAlN, TiN, TiCN and other composite nitrogen. The compound forms a composite coating structure. The cutting of the drill bit is increasing at a high speed, and the cutting speed can reach 200 to 300 m/min, respectively, depending on the material to be processed. The newly developed SU, ST, and SH solid carbide drills are optimized for the grooved structure combined with the nc-TiAlN coating to reshape the performance of the solid carbide twist drill. The large chip space and the sharp curved edge make the chip removal smooth, forming a unique high rigidity and high durability, which is especially suitable for efficient processing of mass production of automotive parts. At present, the processing of high-precision holes, threaded holes, bolt holes, etc. is progressing toward high-speed cutting. The cutting parameters of the drilling tool are similar to those of the ball end mill, and it also shows the trend of high speed and large feed. Cutting practice proves that increasing the cutting speed is beneficial to the rationalization of the chip shape and improving the surface roughness of the machined surface; increasing the feed rate is very beneficial for chip breaking, chip removal and tool life extension. Therefore, in the future, drilling tools will continue to develop along the direction of high speed and large feed. 4 Conclusion In recent years, China's tool industry has faced fierce competition in domestic and international markets, actively carried out key technological transformations, introduced advanced foreign technology and equipment, and comprehensively improved the technological level and manufacturing capabilities of enterprises, and made great progress. However, it must be clearly seen that domestic tool companies still have a large gap in terms of technology level, production process and manufacturing equipment compared with their foreign counterparts. The quality of the manufactured tool products, processing life, reliability, technical services, etc. The aspect is still not fully able to meet the growing needs of users. Therefore, we have a long way to go, we still have a lot of work to do, there is still a long way to go, we have to work harder.
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