China's foundry industry status quo and development strategies
China's foundry industry status quo and development strategies
Yan Aimin (Ahui Research Institute of Mechanical Science)
1, the status of China's foundry industry
The foundry industry is a traditional industry with a long history. Casting occupies a very important position in machinery manufacturing, casting technology is one of the main technologies for the sustainable development of the national economy. For example, in the machine tools, pumps, diesel engine and other products on the castings accounted for 80%; in television, coal mining machinery and other products accounted for more than 45%; in automotive products accounted for 30%. In the industrial policy of China's automobile manufacturing industry, casting production has been listed as a key development product. Since the founding of the People's Republic of China, a large number of scientific and technical personnel in the foundry industry in China have carried out a large number of effective basic theories and applied technology research, which has brought China's casting technology level to or close to international standards in many fields and has achieved remarkable results.
1.1 Casting Industry Scale and Casting Production in China
According to reports, there are about 22,000 foundry factories in China, and the total number of employees is more than 1.2 million, of which about 3.5% are engineers and technicians. The number of factories and the number of employees in the industry ranks first in the world. Since the reform and opening up, China's foundry companies have introduced a large number of foreign advanced casting technologies and equipment and advanced management techniques through technological transformation or joint ventures, which has increased their efforts in digestion, absorption and independent research and development, and formed a batch of economies of scale and product quality. This is the cornerstone of the development of the foundry industry in China, which has reached the international advanced level and has exported high-level castings to modern casting companies. In addition, there are a number of scientific research institutes engaged in the research of foundry technology and institutions of higher learning that cultivate advanced technical talents for the development of the foundry industry. This provides a strong support for the sustainable development of the foundry industry.
China's foundry companies can produce various kinds of castings, which can basically meet the needs of national economic development and can be partially exported. In recent years, the output of castings in China is between 10 and 12 million tons, ranking second only to the United States. However, in the year 2000, statistics of state-owned 9,374 companies showed that the output of castings reached 13.95 million tons, surpassing that of the United States for the first time (1312). 10,000 tons, ranking first in the world, which fully shows that the demand for castings is increasing in all sectors of the national economy. The foundry industry is promising. In recent years, the export of castings in China has also increased year by year. It was 403,000 tons in 1993, 665,000 tons in 1995, 1.04 million tons in 1998, and 1.1 million tons in 1999. Currently, the export castings account for about 10% of the total casting output. After China's accession to the WTO, the export volume of China's castings will have greater growth.
1.2 Progress of China's Foundry Technology
1.2.1 Modeling Materials and Casting Process
(1) Sand processing
Since the 1980s, sand casting has imposed higher requirements on the performance of natural silica sand, and thus natural sand processing techniques such as washing, scrubbing and flotation have emerged, and a production capacity of 10 million tons has been formed.
(2) Cast coating
China basically solved the problem of production and supply of water-based and alcohol-based paints for cast iron castings, and successfully developed V-methods, metal molds, cast pipes, and special paints for lost foam.
(3) Casting process
The traditional casting process has made significant progress. Sand casting adopts advanced production equipment and advanced manufacturing technology. Special casting, continuous casting and continuous casting and rolling processes have been applied one after another. China has established various types of molding lines and core lines up to 500, including high-pressure molding, electro-magnetic micro-pressure shock, box-free injection pressure, resin sand, air punch molding, metal-type sand, v-form, lost foam casting, etc. .
1.2.2 Cast Alloy Material
(1) Casting Alloy Material
In the second half of the 20th century, China was particularly active in the research and application of cast alloy materials. The production technology of rare earth nodular cast iron with Chinese characteristics, such as quenched ductile iron, has reached the international advanced level, and has been widely used in diesel engines, agricultural machinery, automobiles, gears and anti-wear parts and other mechanical products. The application range has been expanding, and the output has increased significantly year by year. The vermicular cast iron has been applied to exhaust pipes, high horsepower diesel engine heads, glass molds and other products; high-strength, high-elasticity gray cast iron, wear-resistant wear-resistant alloy cast iron, high-strength gray cast iron has been in the machine tool rails, The application of diesel engine cylinder liners, cylinder blocks, cylinder heads, piston rings, and grinding balls has achieved good results; In addition, alloy cast steel, non-ferrous metals, and cast composite materials have also been developed and applied. It is worth mentioning that after more than ten years of research and development, the foundry scientists and technicians in China have formed a production base for inoculants, nodulizers, and vermicularizers, which has facilitated the development and application of cast alloy materials. .
1.3 Computers are increasingly used in foundry production
The application of computers in foundry production will lead to the development and fundamental deterioration of the foundry technology. After more than 20 years of hard work, relevant universities, research institutes and key casting companies in China have achieved the results of the points. Computer-assisted design, composition and mechanical performance assisted design, numerical simulation of the solidification process and temperature field of casting alloys, numerical simulation of the filling process of castings, casting process, quality of casting alloys, quality of castings, and testing and control of casting equipment have been carried out. Foundry database, management, computer graphics, robots and robot applications, etc., and applied in the production, its wider application range, and achieved good economic benefits.
2, Problems in China's Foundry Industry
After decades of efforts, China's foundry industry has made significant technological progress, but there is still a large gap compared with advanced foundry countries.
2.1 Economic Scale
Since the reform and opening up, with the establishment and continuous improvement of the socialist market, the number of factory points in China's foundry companies has been increasing, but there are many factories, small scale, and low degree of specialization. The situation is still outstanding. According to the calculation of 13.95 million tons of castings in 9,374 state-owned foundry enterprises in 2000, the average output of each enterprise is about 1,599 tons. If calculated by 22,000 foundry points, the average output of each foundry is less than 1,000 tons. Among them, those with an annual output of 300 tons or less accounted for about 33.7%; those with an annual output of 300-500 tons accounted for 53.3%; and those with an annual output of more than 5,000 tons accounted for only 17%. However, the average size of foundry companies in industrialized countries are all above 5000 tons. The total labor productivity of our country is about 12 tons per person per year, and the per capita output value is about 45,000 yuan per person per year. The per capita annual output of developed countries is 60 to 80 tons, and the per capita annual output value is over 300,000 yuan.
2.2 Overall casting quality
Since the reform and opening up, China's casting production technology has made significant progress, but it is still one of the few key enterprises that can produce high-quality castings. In general, there is a big gap between the appearance quality, inherent quality, and consistency of quality of the castings compared with foreign countries. The dimensional accuracy of castings is generally 1-2 levels lower than that of foreign countries, and the surface roughness is 1-2 levels worse than that of foreign countries. The wall thickness of castings is much thicker than that of foreign countries. Taking the cylinder block of engine cast iron as an example, all overseas adopt HT250, and many enterprises in China still use HT200; China's casting size accuracy is CT8-CT12, roughness is 25um-100um, wall thickness is 4.2-4.5±0.8 ~1.0mm, while the foreign casting size accuracy is generally CT6-CT8, roughness is 12.5um-25um, wall thickness is 3.2 ± 0.5mm. Concerning the material composition of castings, China still uses gray cast iron as the main material, accounting for approximately 61.9% of the total casting output (including about 70% of the HT250 grades), and ductile iron accounts for about 16.7%, which is lower than the world average (>20%). Far lower than Japan (30.8%) and the United States (29.6%). The proportion of alloy steel in steel castings is 25% in China and 42%-60% in foreign countries. In addition, there is a large gap between the consistency and stability of the material composition, organization, and performance compared with the developed countries in the foreign foundry industry.
2.3 Basic conditions for casting production technology and equipment
China's casting production process, technical equipment, backward production process control, incomplete detection means, is caused by China's casting quality is not high, one of the important reasons for poor economic efficiency.
Smelting: Casting coke is commonly used to cast cast iron in foreign countries. The temperature of hot metal is above 1500°C. Metallurgical coke or local coke is commonly used in China, and less than 1% of foundry coke is used. The temperature is generally lower than 1400°C; in the smelting of alloy steels in developed countries, AOD and VOD equipments are mostly used, but China still uses the original electric furnace production methods; the smelting of non-ferrous alloys, the vast majority of China still use foreign fuels that have been eliminated. Coke boilers.
Moulding and Core Making: In China, except for a few key foundries for automobiles and internal combustion engines that use high-density static pressure, injection pressure, and air-jet molding machines and other efficient line molding, Most foundries still use shock pressure modeling or manual molding, and core production is still based on tung oil, synthetic fat, and clay sand.
Process Design: CAD/CAM is commonly used abroad, except for a few companies in China, most of them are designed with the experience of technicians.
Casting raw and auxiliary materials: The production and supply of foreign foundry raw and auxiliary materials has formed a set of socialized, specialized, and commercialized systems. After years of hard work, China has made great progress, but there is still a big gap with the developed countries.
2.4 Energy Consumption and Pollution
According to information, the energy consumption of casting production in China is about twice that of the founding countries. The energy consumption per ton of qualified castings produced in China is 550 to 700 kg of standard coal, 300 to 400 kg of standard coal is used abroad, and the energy consumption of China's 1 ton of qualified steel castings is 800 to 1,000 kg of standard coal, while that of foreign countries is 500 to 800 kg of standard coal. .
According to statistics, the input of materials and energy in the casting production process in China accounted for about 55-70% of the output value. About 1 ton of qualified castings are produced, approximately 300kg of waste residue and 50kg of dust are to be discharged. Exhaust gas 1000 ~ 2000m3, waste sand 1.3 ~ 1.5 tons. The total amount of pollutants discharged by the entire foundry industry is: 4.2 million tons of waste residue, 700,000 tons of dust, 140-279 billion m3 of exhaust gas, and 1810-20.90 million tons of waste sand. This shows the seriousness of the environmental pollution in the foundry industry. In foreign countries, the emission of three wastes of one ton of qualified castings is less than one tenth of that of China. In developed countries, foundry plants are used for environmental protection investments that account for 20-30% of investment in foundry equipment, while China only accounts for 5-18%.
3, Countermeasures for the development of the foundry industry
The guiding ideology for the development of the foundry industry is to take the market as the orientation, focus on the adjustment of industrial structure, take the upgrading of industrial technology as the goal, use advanced technology as the means to strengthen technological innovation and corporate culture construction, and improve the quality of castings, economic benefits, and markets. Overall competitiveness.
3.1 Accelerate the pace of modern enterprise system construction and do a good job in industrial restructuring
To adhere to the basic principles of reform, reorganization, transformation, and strengthening of management, intensify the reform of the enterprise, and accelerate the construction of "clear property rights, clear rights and responsibilities, separation of government and enterprise, and management science." Modern enterprise system. We must actively explore and improve the adjustment of property rights and ownership structure in the light of reality. Casting companies with low overall quality and poor performance will implement "returning from the country". While establishing a modern enterprise system, we must also strengthen corporate culture and scientific management. Market-oriented, through market research and analysis, to grasp the direction of market development. It is necessary to apply scientific and effective management methods and correctly formulate the company's development strategy.
3.2 Strengthen industrial structure adjustment and optimization to form a reasonable economic scale
Profits and ownership adjustments should be used as opportunities to effectively adjust and optimize the industrial structure to form an economic scale focused on product specialization. The powerful foundry companies have achieved a highly competitive economic scale through mergers, reorganizations, and alliances based on the laws of market economy. Small businesses follow the path of “professionalism, refinement, and speciality” and build professional small-scale foundries with lean personnel, flexible operation, and strong resilience. Through cooperation and establishment of corporate networks, they establish partnerships with large-scale enterprise groups and complement each other. Improve the socialization of production and form your own competitive advantage.
3.3 Strengthen technological progress and improve technological innovation capabilities
Technical innovation is a systematic project. It is necessary to grasp the "three combinations", that is, the combination of technological innovation and institutional innovation, the combination of technological innovation and technological transformation, and the relationship between technological innovation and structural adjustment. Combine. Enhancing enterprise technological innovation ability is the key to improving the core competitiveness of enterprises. It is necessary to establish and perfect the technological innovation system with enterprises as the main body as soon as possible. First, to speed up the construction of technological innovation capabilities of enterprises, large and medium-sized foundry companies must establish enterprise technology centers. The second is to actively promote the joint development of production, learning and research. Third, gradually increase investment in technological innovation of enterprises, and focus on the development of high-tech and new technologies such as computer-aided design, auxiliary manufacturing, auxiliary process management, computer integrated manufacturing systems, computer simulation technology, agile manufacturing technology, rapid response manufacturing technology, and precision manufacturing technology. The application of materials and new techniques in casting production will use high technology to transform and upgrade casting companies and promote the upgrading of enterprises' technologies.
3.4 Actively adopt advanced and applicable casting technology and equipment to continuously improve the quality of castings
If casting companies want to increase their product quality, gain an advantage in market competition, increase their market share and increase their export ratio, they must carry out the process equipment that cannot guarantee the improvement of casting quality. Technological transformation. Enterprises should adopt advanced, mature and applicable process technologies and equipment suitable for the company's conditions according to the product quality requirements. It is necessary to continuously improve the grade and quality of casting products by optimizing the structure of casting production technology. While strengthening production management, enterprises must strengthen product quality management, strengthen quality awareness, establish and improve quality assurance systems, improve inspection methods, and promptly revise enterprise product quality standards, produce according to internationally recognized quality standards, and increase the competitiveness of enterprise products. .
3.5 Develop Green Casting Technology to Improve Cleaner Production Level
The foundry industry is an industry with large resource consumption and harsh working conditions. Its dust, flue gas, waste residue, waste sand, waste water, and noise all contribute to the social environment and human health. . Many foundry companies in the cities have been forced to relocate to suburbs, rural areas and even mountainous areas due to environmental issues. However, no matter where they are moved, if they do not take environmental protection measures, the hazards still exist. The first is to reduce the sources of pollution by shutting down small-scale, technologically backward, inferior product quality, and heavily polluting foundry sites through the industry. The second is to actively promote the use of casting environmental protection new technologies, new materials and equipment that are suitable for the country’s situation and are effective. Third, the relevant government departments actively support the research and development of advanced technologies and clean production technologies. They must implement the limited goals, highlight the priorities, and select the best ideas for development. They should focus on the development of new technologies, new processes, high-quality, high-efficiency, energy-saving, material-saving, and less-pollution technologies. New materials, new equipment. Fourth, as the main body of clean production, enterprises must also invest in capital, and increase the research, development and application of clean production and environmental protection technologies. Enterprises must create conditions, implement the ISO14000 environmental management system standards, and pass certification as soon as possible to gain competitive rights to participate in the market.
3.6 Enhancing Market Development Capabilities and Improving Trade Awareness and International Management Level
After China's entry into the WTO, domestic foundry companies will be integrated into the world economic trend. In the face of fierce competition in foreign markets, enterprises will require higher market development capabilities. Enterprises should raise their awareness of trade and economics, be familiar with WTO rules, and apply the WTO anti-dumping laws and relevant laws and regulations of China to enhance their self-protection capabilities. Second, under the premise of ensuring quality, efforts should be made to reduce production costs and increase product competitiveness. It is necessary to rely on sincerity and strictly implement product contracts and delivery dates to increase the level of international operations.
3.7 Implement Talent Strategy and Create Excellent Employment Mechanism
Talent is the key factor in determining the rise and fall of a business. Foundry companies face the fierce market competition, but also face the talent competition of domestic and foreign companies. In order to survive and develop in the fierce market competition, enterprises must implement a talent strategy, which must be advancing with the times and people-oriented. The first is to formulate a policy for attracting and stabilizing talents for science and technology, striving to create a good atmosphere for retaining talents, attracting talents, respecting talented people, protecting talents, retaining people from undertakings, keeping policies, keeping people in good standing, and outstanding talents. Second, we must create conditions for creating talents. To attract scientific and technological talents to work in enterprises, the third is to strengthen the building of a talent team and create a large number of composite talents who are good at science and technology to welcome new and operational management. Fourth, it is necessary to strengthen the training of all staff and comprehensively improve the skills and quality of employees.
From "Foundry World Report"