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China's CNC machine tools have achieved great development in terms of product category, technology level, quality and output, and have made major breakthroughs in some key technologies. According to statistics, currently there are 1,500 kinds of CNC machine tools available in the market in China, covering almost all types of metal cutting machine tools and the major forging machinery. The wide area can be matched with Japan, Germany, and the United States. This indicates that the domestic CNC machine tools have entered a period of rapid development.
In recent years, China's machine tool industry has continuously undertaken the task of providing high-level numerical control equipment for the national key projects and defense military construction. For example, the domestic XNZD2415 CNC gantry hybrid machine tool fully absorbs the advantages of flexible configuration and diversity of the parallel machine tool and the large processing range of the traditional machine tool. The basic gantry is formed by a two-degree-of-freedom parallelogram parallel mechanism, and a two-degree-of-freedom series structure is added on the parallel platform. The A, C-axis pendulum heads, coupled with the longitudinal movement of the table, can complete five degrees of freedom of movement. This configuration is the first in the world. Based on the real-time and reliability of the RT-Linux developed CNC system, it can be connected to multiple PLCs in the same network, and can control the five-axis linkage of the machine tool to realize human-machine dialogue. The working space of this machine is 4.5mx1.6mx1.2m, A-axis angle ± 1050, C-axis continuous rotation angle 0-4000, spindle speed (stepless) up to 10000r/min, repeatable positioning accuracy ± 0.01mm, three-dimensional Surfaces such as turbine blades and guide vanes are five-axis high-speed machining.
Ultra-precision spherical lathes provide basic equipment for the processing of gyroscopes. These lathes can also be used for the processing of lens molds, camera plastic lenses, bar code reading devices, and lasers, etc.
High-speed five-axis gantry milling machine adopts oil mist lubrication and cooling in the milling head, cross beam pre-stress anti-deformation control and other technologies. This type of milling machine can be used for processing aerospace, aerospace, shipbuilding, water pump blades, and high-grade molds.
The SSCKZ80-5 5-axis turning and milling compound machining center can meet the requirements for processing of large-scale, high-rigidity, and complex-shaped large-scale rotary parts in the aerospace, aviation, shipbuilding and railway transportation industries, such as the machining of aircraft engine spindles and landing gears. Ship engine piston, supercharger worm differential commutator and spiral blade processing.
The TW250 high-speed, high-efficiency turning center adopts a double-spindle structure. The two tool holders are located on the axis of the spindle, and the number of control axes is 8, and 4-axis linkage can be realized. The upper and lower tool holders equipped with 12-position servo-driven bidirectional power tools can perform either 2-axis or 4-axis machining on either spindle. The machine tool adopts modular design technology and can be derived as double-spindle double-spindle, single-spindle double-spindle, double-spindle single-spindle, and other turning centers or CNC lathes according to the user's different requirements.
The XKAE2720 bridge beam girder gantry machining center can meet the needs of the aviation, aerospace, military, locomotive vehicles, molds, printing machinery and other industries.
MJ-860DT double-turret 4-axis counter CNC lathe is a large-scale, heavy-load, high-stiffness, multi-axis control CNC lathe, suitable for large-scale workpieces (such as high-strength heat-resistant titanium nickel Alloy steel parts) for strong cutting at low and medium speeds are also suitable for metallurgy, locomotive, papermaking machinery and other industries for high-efficiency and powerful turning of large workpieces, especially long-axis parts.
TK68125A floor type CNC boring and milling machine can be widely used in large and medium-sized diesel engine, engineering machinery, automobile, shipbuilding, aerospace and aviation industries. It is especially suitable for high-speed and high-efficiency machining of complex parts with space curved surfaces.
TK6913B floor-standing CNC boring and milling machine has formed its own core technology in high rigidity square ram, CNC movable spindle assembly, CNC rotary table, CNC rotary dial, large chain magazine, modular development and other aspects.
Shaanxi Hanjiang Machine Tool Co., Ltd. regards the high-precision ball screw pair and the rolling linear guide pair for the numerical control machine tools as the main attack direction. In 2004, it produced 50,000 sets of ball screw pairs and 20,000 sets of rolling linear guides, among which were CNC machine tools. Supporting high-precision products account for more than 80% of production and sales. Yantai Global Machine Tool Accessories Co., Ltd. takes advantage of the strong driving force of enterprise restructuring, fully implements the industrialization strategy, and promotes the development of the company. In 2004, the sales revenue of CNC machine tools' functional components reached more than 40 million yuan. Compared with 2003, the output of CNC tool holders increased by 121.24%, and the output of CNC rotary tables and numerical control index heads increased by 45.6%.
Luoyang Axis Research Technology Co., Ltd. has developed and produced 8 categories, 13 series, more than 160 kinds of electric spindles and spindle units. In 2004, domestically-made drive units were used to support domestic electric spindles, and high localization reduced the production cost of the products, thereby increasing the competitiveness of the main plant.
At the end of 2004, Lilim in Vietnam. In the international bidding for CNC machine tools organized by the company, Wuhan Heavy Machine Tool Group defeated rivals such as Germany and Romania and won an order for a CNC double-column heavy-duty vertical lathe with a machining diameter of 8m, which created the largest export of large-format CNC machine tools in China. In January 2005, Wuzhong Heavy Machinery Co., Ltd. valued US$500,000 for CKJ5255/I type ¢5.. 5m heavy duty CNC lathe exported to Thailand. According to user SCI, this product will be used for the valve body processing of the country's very large valves and is Thailand's largest imported mechanical processing equipment to date. : Wuzhong's CKX53160 16m super heavy-duty, single-axis, vertical turning and milling machine originally had only three companies from the Czech Republic, Germany, and Russia in the world. Wuzhong independently developed and produced five units, and its function was continuously improved. According to reports, Wuzhong has made repeated gains in the heavy-duty and super-heavy-duty machine tool industry for many years. Its numerically controlled vertical-vehicle products have a market share of 60% in the domestic market, and the market competitiveness of boring machines and milling machines also ranks in the forefront.
At present, China has been able to supply networked, integrated, and flexible CNC machine tools. At the same time, China has also entered the ranks of the world's high-speed CNC machine tools and high-precision precision CNC machine tool manufacturing countries. At present, China has successfully developed a number of CNC machine tools with spindle speeds of 8000-10000 r/min or more. In recent years, China's CNC machine tool industry has vigorously promoted the use of CAD and other technologies. Many companies have started and plan to implement ERP, MRPII, and e-commerce.
Second, China's huge market for CNC machine tools
At present, China is in the middle period of industrialization, that is, from the solution of the shortage-based opening to the gradual transformation of building an economically strong country, from the shift from poverty alleviation to wealth, coal, automobiles, steel, real estate, building materials, machinery, electronics, chemicals, etc. are based on heavy industry. The strong growth momentum of the high-growth industry constitutes a huge demand for the machine tool market, especially CNC machine tools. According to the KPMG accounting firm's analysis, China has surpassed Germany to become the world's largest machine tool market. In 2005, market sales will reach 7 billion US dollars. CNC machine tools have become the mainstream of machine tool consumption. China's future market for CNC machine tools is huge. It is estimated that the consumption of CNC machine tools will still exceed 6 billion U.S. dollars in 2010, and the number of machines will exceed 100,000 units. Experts pointed out that the proportion of medium-to-high-end CNC machine tools will increase substantially, the proportion of economic-type CNC machine tools will not change much, and the demand for non-CNC-based ordinary machine tools will be greatly reduced.
The Investment Research Institute of the State Planning Commission predicts that during the “10th Five-Year Plan†period, China’s total investment in fixed assets will reach 22 trillion yuan, and the average annual growth rate will be 37%. According to the interaction between fixed asset investment and machinery market consumption in the past, during the “10th Five-Year Plan†period, the business opportunities bred by China’s machinery market amounted to RMB 320-400 billion. In terms of transportation, during the “10th Five-Year Plan†period only RMB 100 billion will be invested in Western Railway development, and in the next 10 years western traffic will be invested RMB 7,000 to RMB 800 billion. Special equipment such as wheel lathes, 2m large-scale sawing machines, and spiral welded pipe expansion machinery are useful. In the next five years, the water conservancy project will invest 530 billion yuan, the first phase of environmental protection investment will be 188.8 billion yuan, the second phase investment will be 260 billion yuan, and the corresponding machinery and equipment will have huge demand; 300 machinery manufacturers will carry out technological transformation, and the number of CNC machine tools to be purchased will be very impressive. . In 2004, there were about 17,000 mold factories in China with an annual production value of about RMB 53 billion. The required machinery is biased towards high-precision, high-efficiency, high-speed milling equipment, virtual-axis machine tools, compound processing machines, and slow-cut wire cutting. Machine and so on.
According to reports, during the “Eleventh Five-Year Plan†period, the state’s investment in the equipment manufacturing industry will be mainly concentrated in aerospace, aviation, shipbuilding, automobiles, weapons, machinery, and electronic information industries.
The subcontracting and production of civil aviation passenger aircraft in the aviation industry has further expanded. With the United States Boeing and European Airbus subcontract production of passenger aircraft parts will increase significantly; with foreign cooperation in the production and self-development of military aircraft and military helicopters will enter the batch. The manufacture of aircraft wings, fuselage, and tail fins, and engine parts requires a large number of high-speed five-axis machining centers, gantry mobile high-speed machining centers, precision CNC lathes, precision horizontal machining centers, multi-axis boring and milling centers, precision gears, and thread processing. CNC machine tools and so on.
In 2005, the aerospace industry will concentrate on launching the Shenzhou-6 spacecraft. During the “Eleventh Five-Year Plan†period, moon-flying satellites and dozens of various space satellites will be launched. The aerospace industry requires a large number of precision, high-speed, small and medium-sized CNC machine tools, such as precision CNC lathes and turning centers, vertical and horizontal conversion five-axis machining centers, high-precision electric machining machines, high-precision universal grinding machines, and coordinate grinders.
In 2004, China produced 8 million tons of shipbuilding, accounting for 15% of the world's shipbuilding market and ranking third in the world. Shipbuilding will reach 10 million tons in 2005, accounting for 18% of the world's shipping market. During the "Eleventh Five-Year Plan" period, China's shipbuilding industry will have great development and become a powerful shipbuilding nation in the world. At present, apart from Shanghai Waigaoqiao, which is building a large-scale ship assembly plant with the highest level of modernization, the largest scale, and the most advanced technological facilities, the two major shipbuilding industry groups, the South and the North, are also planning to build and expand an extra large shipbuilding company. The shipbuilding industry is in urgent need of manufacturing heavy-duty, ultra-heavy gantry milling boring machines for heavy-duty diesel engines and heavy-duty CNC floor boring and milling machines as well as large CNC lathes and turning and milling centers, large CNC gear grinding machines, crankshaft boring and milling machines, large crankshaft turning and milling centers and crankshaft grinding machines.
The automobile manufacturing industry is a large demand for machine tools, accounting for about 40% of the total consumption of machine tools. In 2005, the annual automobile production in China will reach about 5.6 million vehicles, and by the end of the “Eleventh Five-Year Planâ€, it will reach 80.1 million vehicles. At the same time, the output of automobile parts will increase substantially. The automotive industry needs a large number of high-efficiency, high-performance, special-purpose CNC machine tools and flexible production lines, such as flexible production lines mainly for high-speed horizontal machining centers for engine machining and CNC machine tools for crankshaft machining. Automotive parts production demand a large number of CNC lathes, vertical and horizontal machining centers, CNC high-efficiency grinding machines and CNC gear processing machine tools.
The demand for the manufacturing of weapons and equipment for numerical control is even more extensive and requires reliable and stable CNC machine tools. Domestic CNC machine tools have a large market space. Weapons manufacturing industry needs a large number of CNC lathes, vertical and horizontal machining centers, five-axis machining centers, gantry boring and milling machines, boring and milling machining centers, and gear processing machine tools.
In 2004, China's newly installed power generation capacity was 71.38 million kW, a record in history, but the nation’s electricity supply and demand remained tight. During the “Eleventh Five-Year Plan†period, the power industry will continue to maintain rapid growth. The power generation equipment manufacturing industry needs heavy-duty CNC boring and milling machines, large-scale floor boring and milling machines, large-scale CNC lathes, blade root groove-specific milling machines, and blade NC machining machines. The power transmission and transformation equipment manufacturing industry needs CNC lathes, machining centers, and CNC boring machines.
The metallurgical equipment manufacturing industry will focus on the manufacture of continuous casting and rolling complete sets of equipment, and demand for large-sized gantry milling machines, large CNC lathes and other equipment.
China's railways, highways, energy, water conservancy, airports and towns and cities need a lot of construction machinery. The construction machinery manufacturing industry needs a large number of small and medium-sized CNC machine tools such as CNC lathes, medium-sized machining centers, CNC milling machines, and gear processing machines.
In 2004, the national mold output value increased by 17.8% year-on-year. China's current large-scale, sophisticated, complex, long-life mold is still a large number of imports, in 2004, imports of mold 1.872 billion US dollars, an increase of 32.4%. The mold market is mainly concentrated in East China and South China, accounting for approximately 75% of national sales. Recently, Jiangsu Suzhou has been planning to build the largest mold manufacturing base in Asia. The mold manufacturing industry demands high-speed CNC milling machines, coordinate measuring machines, precision electric machine tools, high-precision machining centers, and precision grinding machines.
99.5% of the equipment in the electronic information equipment manufacturing industry depends on imports. In 2004, the import value reached 10 billion yuan. The industry needs a large number of small precision CNC machine tools such as high-speed milling centers, high-speed machining centers, small precision lathes, small precision presses, precision and ultra-precision machining-specific CNC machine tools, and precision electric machine tools.
Third, domestic CNC machine tools are still lagging behind
The important components of CNC machine tools include CNC systems, tool magazines and robots, CNC tool holders and turntables, spindle units (electric spindles), ball screws and rolling guides, protective covers, and numerical control tools. The performance has become a determinant of the overall performance. The CNC system consists of a display, servo controller, servo motor, various switches, and sensors. Of course, the development of ordinary machine tools to CNC machine tools is not just a matter of adding systems. For example, from the development of milling machines to machining centers, the structure of machine tools has changed. The most important thing is to increase the number of magazines, and the accuracy has been greatly improved. The main function of the machining center is milling, boring and drilling. Currently the world's three largest manufacturers are: Japan's Fanuc, Germany's Siemens, Japan's Mitsubishi, and its products are widely spread, but the technology is not necessarily the highest, and the rest are France Num, Spain Van Gogh.
The numerical control machine tool uses the binary mathematics method to input, the processing process may arbitrarily program, the main axle and the feed speed may change according to the processing craft need, and may realize the multi-coordinate linkage, the easy processing complex surface. For the processing object has "variable, changeable, changeable" features, change batches to facilitate the adjustment, can achieve complex varieties of medium and small batch of flexible production, meet the community's demand for product diversification. However, the price is relatively expensive, and it is necessary to correctly analyze the economic rationality of its use. The combination of hardware and software can realize the functions of information feedback, compensation, automatic acceleration and deceleration, and can further improve the machining accuracy, efficiency, and automation of the machine tool. CNC machine tools are electromechanically integrated machine tools that are mainly electronically controlled. They give full play to the unique advantages of microelectronics and computer technology. They are easy to implement informatization, intelligence, and networking, and can easily form various advanced manufacturing systems, such as FMS. , FTL, FA, and even future CIMS can maximize the company's labor productivity.
CNC machine tools are a combination of mechanical, electrical, liquid, gas and light multidisciplinary high-tech, especially based on modern advanced technologies such as electronics and computers. They must have a solid technical foundation and are mutually compatible. If not all, CNC machine tools are difficult to develop smoothly. CNC machine tools are composed of three main parts: host computer, various components (functional parts) and numerical control system. They also need advanced automated tooling to achieve the processing. Each link must be practically cleared in terms of technology and quality to ensure reliable work. Stability can ensure the precision, efficiency and automation of CNC machine tools. Otherwise, it is difficult to use in actual production.
The overall technological development capability and technical foundation of the CNC machine tool industry in China is weak, and the application of information technology is not high. The existing source of informatization technology in the industry mainly relies on the introduction of foreign technology, and the foreign parties have control over the core technologies of many high-tech products. Our dependence on foreign technologies is relatively high, and the introduction of imported technologies still remains in the grasp. The increase in the technology and localization rate has not risen to the extent that it has formed the ability to independently develop products and technological innovation. The high-performance and practical CNC machine tools with high precision, high speed, high efficiency, compound functions, and multi-axis linkage basically rely on imports.
Compared with foreign products, the gap in China is mainly due to the high-speed, high-efficiency and precision of machine tools. For high-speed machining technology, research abroad has been conducted for many years, systematically studied the mechanism of high-speed machining, machine tool structure, machine tool stiffness and precision, and developed a variety of high-speed milling centers, high-speed machining centers, Widely used in aircraft aluminum alloy parts and mold processing.
The high speed machining center of foreign ball screw driven high speed machining speed is mostly above 40m/min, the maximum has reached 90m/min, the processing center of linear motor drive reaches up to 120m/min; while the domestic machining center fast feed is mostly at 30m Around 60 min/min, individual processing centers driven by linear motors have only prototyped samples. The spindle speed of foreign high-speed machining centers is generally 12,000-25,000r/min, and the maximum has reached 70,000r/min. In the structure, it adopts the unique box-in-box structure or gantry-type structure adapted to the requirements of high-speed machining.
According to statistics, China's large-scale high-performance super-precision machine tools produce less than a thousand units a year, accounting for only 1.5% to 2.5% of the total domestic machine tools and total value, less than 1/20 of Germany or Japan. Foreign horizontal machining centers are equipped with machine tool accuracy and temperature compensation systems, and machining accuracy is relatively stable, while domestic research and development is still in progress; positioning accuracy of foreign machining centers is basically in accordance with the German standard VDI3441 acceptance, the following stroke 1000mm, positioning accuracy can be controlled at 0 Within .006-0.0lmm, but the domestic positioning accuracy is relatively low.
In 2004, China's metal processing machine tool consumption reached 9.5 billion U.S. dollars, accounting for 1/5 of the world total. Among them, the import share accounted for 63%, and the import value of CNC machine tools was 3.4 billion U.S. dollars, accounting for 78.6% of all imported metal cutting machine tools. In order to meet the needs of the manufacturing industry, the country spends over one billion US dollars each year to introduce CNC machine tools. The core technology of CNC machine tools is the CNC system. 90% of our products are imported from abroad. Not only is the price high, the long import cycle can not meet the requirements of the host plant. Moreover, the reliability and quality of the machine tools assembled using imported devices will also be affected. In 2004, about 10,000 units were consumed in the Mainland, but the total number of enterprises on the mainland combined lost about 2,000 units. Taiwan Province, with only eight or nine production and processing center factories, sold 3,300 units to the mainland.
Fourth, vigorously promote the development of CNC machine tools in China
In order to further promote the development of CNC machine tools in China, enterprises must be regarded as the main body of development. Relying on universities and research institutes, the government provides guidance and support in macroeconomic policies, and social intermediary agencies provide high-quality services in order to gradually improve the machine tool industry.
1. Increase government support
From May 26th to 28th, 2005, the “China-made CNC Machine Tool Development Symposium†organized by China Machine Tool Industry Association was held in Dalian. The project centered on the “High-end CNC Machine Tool Application and Demonstration Project†and the “Special Plan of CNC Machine Tool Industry Developmentâ€. In order to meet the technical reform needs of key users and promote the development of domestic high-end CNC machine tools, the National Development and Reform Commission requested the China Machine Tool Industry Association to do a series of substantive work and quickly implement certain key tasks identified in the minutes of this meeting. The meeting also called for checking the commitment made by the machine tool industry at the China CNC Machine Tool Show held in Shanghai in 2006.
According to the “Special Plan for the Development of National CNC Machine Tool Industry,†the next five years, the machine tool industry will create 20 CNC machine tool industrialization bases and 10 supporting basic functional component industrial bases. The base companies will enjoy national policies and funding. stand by. The new products and high-end CNC machine tool products developed and produced by CNC machine tool industrialization bases implement a VAT return policy. The "Planning" will also give support to the enterprises that have entered the industrialization base to the funds of the national debt project. The initial construction of the enterprise technology development center and technical engineering research center, as well as the first and first set of new products, will also be given a certain risk subsidy. If a machine tool company wants to enter the industrialization base, its technology development investment must not be less than 5% of the product sales revenue. If this index is reached, a certain degree of subsidies will be granted to the country each year. If the goals of the "planning" can be achieved, by the end of the "Eleventh Five-Year Plan" period, the domestic market share of domestic CNC machine tools will increase to more than 50%. At the same time, the domestic market share of all domestic machine tool products will also increase to more than 60%.
2. Improve comprehensive application efficiency
In order to improve the overall application efficiency (OAEE) of the equipment, numerical control equipment should be able to operate in a stable and reliable manner over a long period of time, be highly efficient in product processing, and quickly produce quality-qualified product parts. Some domestic experts analyzed the main factors affecting OAEE and proposed to design, implement and implement a digital integrated automation technology based on integrated application integration of people, information, technology, resources, organizations, and management systems from the e-M overall solution technology. Enterprise application integration fundamentally improves the industrial application level of numerical control equipment.
3. Improve development capabilities
Raising development capacity is not an easy task. Nowadays, large companies in the West have adopted a market strategy of blockade and dumping on CNC machine tools. The first is the blockade. The blockade does not result in dumping. Its CNC system was sold at a very expensive price in the Chinese market and gained high profits. Once Chinese companies have developed the same products, they immediately cut prices significantly, even to the cost of Chinese companies. Under this circumstance, the state must give more support to domestic enterprises, just as the United States, Germany, and Japan supported the domestic companies.
4. Develop functional components
Some experts predicted that in the next 5 to 10 years, the machine tool industry will aim more at buying parts and components to assemble machine tools and put them into the market. The machine tool industry must produce high-quality CNC machine tools quickly to meet the needs of the market. The functional components for CNC machine tools must be given priority in rapid development. Today, advanced numerical control systems, high-speed precision spindle units, high-speed rolling components, and numerically-controlled tool carriers have become important indicators of the level of CNC machine tools. Their price also constitutes the main component of the price of the CNC machine tool. A rough calculation of the price of the functional components of the CNC machine tool has accounted for about 70% of the cost of the entire machine.
At present, the production of functional components in China is slow, with few varieties and low levels of industrialization. It cannot meet market requirements and has to rely on imports. Due to the high price of imported functional components, the price of the whole CNC machine tool continues to rise. The CNC machine tools produced in China have almost lost their competitive advantage. The market shows that the same level of CNC machine tools, South Korea's price is almost flat with the price of our country, this phenomenon has a lot to do with the main components of our mainframe production plant to purchase the functions required by the CNC machine tools.
Experts, scholars, and entrepreneurs of the machine tool industry in China have all witnessed the tremendous development prospects of the functional component industry. Many companies have also targeted this market and have initially formed a number of professional manufacturers of functional components through the introduction of technologies, cooperative production or independent development. However, China's functional components manufacturing enterprises are generally small in scale and disperse in their layout; some of them are still attached to host plants or research institutes and have not yet been introduced to the market, thus failing to become leading companies. Some varieties have no supply of commodities; some functional components still have a gap with the products of internationally renowned manufacturers. Enterprises that can produce functional components will not be able to survive for a long time if they do not rationalize the system, do not enlarge the market, and do not raise the current level of products and catch up with the international advanced level as soon as possible. A product from the successful development to a small amount of production, if not form a scale as soon as possible, will not be able to lower the cost, will not occupy the market, it can not create a brand.
5. Speed ​​up the introduction of absorption
According to relevant sources, South Korea uses US$1 to introduce advanced technology and uses US$5 for digestion and absorption, while China uses US$1 to introduce advanced technology and uses 0.2 US dollars to absorb and digest it.
In the past 20 years, international industries have achieved phased changes and shifts. China has seized this opportunity to rely on the export of processing trade and a large number of labor-intensive products, and has increased its national strength as China's manufacturing industry has participated in the international division of labor. Many European and American companies have gone bankrupt or merged due to poor management, such as Ma Hao and Sibina. Japan's economy is sluggish, and many machine tool manufacturers that were famous in the 1980s have closed down, such as the Niigata Iron Works. Shenyang Machine Tool Group purchased the Hess Company in Germany in October 2004 and injected liquidity. It is currently negotiating with Wu Cheng on cross-regional restructuring. Dalian Machine Tool Company has also introduced many advanced technologies from Germany. Shanghai Ming Jing Company also successively acquired Warrenberg in Germany and Chiba Corporation in Japan in 2003 and 2004, and occupied 53.6% and 65% of the shares respectively.
Analysis of Current Situation of CNC Machine Tools in China and Suggestions
First, the achievements of the domestic CNC machine tool industry in recent years