(1) the basic situation of China's foundry industry
According to the relevant data analysis estimates, China has about 20,000 foundries of various types of sites, the number of employees is about more than 1.2 million, with an annual output of 12 million tons of castings or so, casting output value of more than 40 billion yuan, ranked second in the world in 1994, the export of casting of about 550,000 tons, the total value of 3.3 billion yuan. billion U.S. dollars. From the industrial structure, there are a large number of production plants or companies belonging to the host casting plant or foundry; also in the implementation of the process of specialization in the implementation of the development of a large number of independent professional foundries (specializing in the process); there are also reform and opening up since the establishment of the townships of the numerous small foundry sites. In terms of scale and level, both advanced technology, high degree of mechanization, annual output of tens of thousands of tons of castings of large foundries; there are backward technology, simple equipment, basically hand-operated, annual output of castings of hundreds of tons of small foundries. Full labor productivity, cast iron, for example, the national average of 8 to 10 tons / person year or so. General foundry cast iron and steel castings per ton of energy consumption were 550-650 kg of standard coal and 900-1000 kg of standard coal. In the past decade, through technological transformation, a number of enterprises have made greater progress and improvement, the formation of a number of advanced level of casting backbone production plant, but in general, China's foundry industry is still faced with poor economic efficiency, low casting quality, energy, material consumption is high, poor labor conditions, environmental pollution and other serious problems.
Statistical analysis of 1989-1992 shows that the market demand for castings on the prosperity of the trend, China's casting production by alloy type, cast iron parts accounted for 81% to 83%, cast steel parts accounted for 13% to 15%, non-ferrous alloy castings accounted for 3.5% to 4.5%. The annual output of investment castings 170,000 tons, die casting annual output of about 250,000 tons, accounting for 2%.
In 1994, China's production of various types of castings are shown in Table 1-1-1, various types of castings production in the various regions awarded in Table 1-1-2.
(2) the last 5-10 years in China's foundry industry, technological progress and development of change
with the Reform and opening up, as well as the "Seventh Five-Year Plan", "Eighth Five-Year Plan" of technological transformation, so that China's foundry industry has undergone many changes. Casting technology, technical level and casting quality level in general than the previous 10 years has improved somewhat, the emergence of a number of key key foundries with the international level in the 80s. China's casting industry, technological progress and development changes are mainly manifested in:
1) the application of new equipment to improve the level of mechanization of China's casting production.
──machine tools, oil, general and heavy machinery industries such as mass production has introduced more than 80 resin sand production line. At the same time, the domestic development and equipment 5 ~ 20 tons / hour capacity of resin sand technology and equipment applications formed a number of tree finger sand process-based casting production, improve the technical level of casting production, so that China's large and medium-sized castings of the dimensional accuracy of CT9-11 level, the surface roughness up to Ra12.5 ~ 50μm, the quality of its close to the level of international level in the 1980s. At present, China has formed an annual output of more than 700,000 tons of resin sand castings production capacity, and can successfully produce 150-ton weight resin sand cast steel parts. Some domestic factories have been able to adapt to the requirements of the international market, using resin sand process to produce machine tool castings and other castings for export.
--Automobile, internal combustion engine and other industries have introduced 31 punching molding lines in large-volume flow production. On the basis of digestion and absorption, the domestic independent development and development of air-punch molding machine and line 29 sets (articles). As these automatic molding line into production and the use of high-quality fine steel shot cleaning, in our country formed a number of advanced technology using large finger production of castings of the plant, so that part of the foundry production of the cylinder block, cylinder head and box and other castings of the dimensional accuracy of the ISOCT6-8 level, the surface roughness of Ra12.5 ~ 25μm, close to the quality level of similar castings abroad. The quality of the castings is close to the quality level of similar castings in foreign countries. In addition, China has also introduced vertical and horizontal parting of high pressure, injection pressure, extrusion and static pressure and "V" method and other advanced molding production line more than 70, which improves the quality level of China's high-strength thin-walled castings has played a significant role in promoting.
──Disappearing mold process due to high dimensional accuracy (up to 0.2mm or less), surface finish (Ra5~6μm), low production cost, investment, etc., in recent years in Europe and the United States and other countries has been the rapid development. Our country has applied the disappearing mold technology to produce automotive aluminum alloy intake pipe, as well as valves, fittings and other cast iron parts.
── cast iron pipe to be industry has introduced about 10 sets of diameter 1m below the medium-sized ductile iron pipe centrifugal casting equipment, each factory to form 3-5 million tons / year of production capacity. At the same time, the country has developed a ductile iron pipe water-cooled metal-type centrifugal machine and a variety of auxiliary equipment, is expected to centrifugal ductile iron pipe in the next 2 ~ 3 years, the annual output of our country will be a rapid increase in ductile iron pipe.
──Heavy machinery industry, the introduction of AOD and VOD and other furnace refining technology and equipment, with automatic control of 80 tons of large electric arc furnace and other advanced equipment, greatly improving the intrinsic quality of high-grade alloy cast steel parts.
──In recent years, China **** the introduction of various types of core-making machine more than 110 (sets). China has been able to mass produce various types and models of hot core box machine, shell core machine. Triethylamine method of cold core box equipment and core unit after digestion and absorption has been successfully developed or put into use. Core level has improved greatly.
──In recent years, the introduction of more than 100 sets of die-casting machine, and the successful development of their own 16,000Kn die-casting machine. Aluminum die casting level has also improved greatly.
2) the development and application of new materials to improve the service life and reliability of the machine.
── China's rich rare earth resources in casting production has been widely used. Rare earth magnesium ductile iron has been in the automobile, diesel engine, as well as other mechanical products in a large number of applications. Rare earth low-carbon cast steel and heat-resistant cast steel in machinery and metallurgical products have been well applied, and obtain considerable technical and economic benefits.
──High-strength, high modulus of elasticity of gray cast iron has been successfully applied to machine tool castings, improve the accuracy of the machine tool; high-strength thin-walled gray cast iron parts casting technology, so that the thinnest wall thickness of only 4 ~ 6 mm cylinder, cylinder head castings of the body of the body hardness of the cross-section of the difference between the HB<30, the organization of the fine and uniform.
── Peristaltic cast iron has been in the automobile exhaust pipe and high-powered diesel engine cylinder head application, so that the service life of the automobile exhaust pipe increased by 4 ~ 5 times, to more than 100,000 miles.
-High phosphorus, boron and vanadium and titanium wear-resistant cast iron has been in the machine tool rails, cylinder heads and piston rings on a large number of applications, so that its wear resistance and service life increased by 1 to 2 times; high-chromium and low-chromium wear-resistant cast iron has been in a large number of applications in the wear-resistant parts, the service life of the material than the original were increased by 8 to 10 times and 2 to 3 times.
──ZL206 high-temperature and heat-resistant aluminum alloy and ZM6 heat-resistant and high-strength rare-earth magnesium alloy and other new aviation materials.
3) The popularization and application of new techniques and technologies have promoted the improvement of casting technology and the quality of castings in terms of internal and external appearance.
──After more than ten years of research and development, has formed China's own inoculant, spheroidizing agent and creep agent series, and gradually formed according to the national standard of commercial supply of three agents of the production base, and vigorously promote the improvement of the intrinsic quality of China's cast iron parts.
──In recent years, the development and promotion of a variety of advanced cast iron smelting equipment, thereby further increasing the liquid iron temperature, reduce liquid iron oxidation. External hot air (wind temperature 500 ~ 600) cupola has begun to be applied in our country, so that the liquid iron temperature of 1500. cupola - electric furnace duplex melting process has been widely used in large quantities of water and mass production.
-In the cylinder block, cylinder head and other high-strength thin-walled castings and other aspects of high-volume streaming production in the application of the filter technology to improve the intrinsic quality of the castings, reduce the slag hole defects.
──Metal type sand casting technology in the diesel engine crankshaft has been successfully applied, it effectively improves the quality of the crankshaft and yield.
─The company has successfully produced 600,000-kilowatt steam turbine high and medium pressure cylinder blocks, 125,000-170,000-kilowatt hydraulic turbine stainless steel blades, large steel castings with a gross weight of 330 tons, and large aluminum alloy castings with a gross weight of 5 tons and a net weight of 2.7 tons.
──Hot core box, shell core, cold core box and other advanced resin sand core technology has been more commonly used in automotive, internal combustion engines, tractors, machine tools and other industries on the castings, greatly improving the dimensional accuracy of the castings.
──Domestic has successfully developed horizontal continuous casting technology and equipment, and the production of 60~200 and 40x40~200x200 ink cast iron and gray cast iron profiles. The material has a series of advantages such as dense organization, high strength, pressure resistance, high dimensional accuracy and surface finish.
──China's precision casting technology has made great progress, the use of near-net-shape technology to produce aero-engine blades without margins, reaching the international level of the 1980s. At present the production of stainless steel fine casting capacity has reached 10,000 tons / year, its dimensional accuracy and surface roughness to reach the international level, to meet the export requirements.
4) the supply of raw and auxiliary materials began to improve.
The quality and supply of raw and auxiliary materials casting has long been restricting the development of China's foundry industry and improve the quality of castings. After the majority of casting workers for more than 40 years of appeal and hard work, the situation began to improve.
── casting sand, bentonite and other resources for more systematic research and groundwork. Under the unified planning, Inner Mongolia Daling, Bahuta, East and West Duchang, Henan Zhengan, Fujian Dongshan, Pingtan and other more than 30 sand quarries all realize the washing of raw sand, so that the mud content of raw sand is less than 0.8%. At present, the annual output of washed sand from these quarries reaches more than 150~2 million tons, and the annual output of scrubbed sand is more than 500,000 tons.
-China has been able to mass production and commercial supply of resin sand molding and core making with a variety of resins, hardeners and auxiliary materials, as well as commercial supply of resin sand film.
-All kinds of auxiliary materials, such as paint and binding agent, have been introduced and commercialized, laying the foundation for the future development of the system.
──Production of high-temperature high-quality iron casting coke required in China has initially built production bases, the formation of a certain finger scale, in order to stabilize the quality of nodular graphite cast iron parts and high-strength gray cast iron parts to create favorable conditions.
5) advanced testing methods and electronic technology in casting production has been applied and development.
──In recent years in many key to be the backbone of the industry foundry site more direct-reading spectrometers and thermal analyzers, fast and effective control of the furnace metal liquid million points and impurity elements accountant, the use of acoustic frequency, speed of sound, and other testing methods to control the quality of the castings, to ensure that the casting of the intrinsic quality of the reliable and stable.
-Coordinate measuring instrument has been applied in a few large foundries, effectively guaranteeing the dimensional accuracy of molds, core boxes and castings.
──Electronic computers have been used in foundry production. Currently used in production management and various data processing, automated control of the production process, as well as casting process design and other areas.
──Manipulators and robots in the casting production of sand, cleaning process, as well as die-casting mold casting began to be applied.
1.2 Market Demand Analysis
(1) from the casting production status quo and production growth trend of casting demand analysis
According to China's overall national economic development plan envisioned in the 90's China's gross domestic product will be 8% to 9% growth rate. The scale of economic construction will continue to expand, casting exports will also increase, China's casting production is expected to continue to grow. At the same time, due to technological progress factors, such as improving casting dimensional accuracy, thin casting wall thickness, long casting service life, expanding the application of light alloy castings, the use of engineering plastics, dirty stamping - - welded structural parts, etc., casting production is forecasted to continue to grow at an average annual rate of about 4%. By 2000, China's annual output of castings will reach about 13.5 million tons.
(2) from the focus of the host product development casting demand analysis
─ ─ automotive castings rise, to 2000, the type of automotive castings will reach 1.5 million tons per year.
──Because of the prosperity of the construction industry and the country's vigorous development of water, oil, gas pipeline, cast iron pipe production will grow at a faster rate, to 2000 will be more than 2.3 million tons. Centrifugal ductile iron pipe due to the introduction of nearly 10 sets of hosts have been put into production, to 2000 when its output will exceed 500,000 tons, so that its proportion in the cast iron pipe from the current 5% to 20% to 25%.
── Railway locomotives, power generation equipment, metallurgical mines and a variety of specialized machinery due to national investment in infrastructure tilted to a greater growth is expected by the year 2000 when the production than the current production growth of more than 30%, castings production will also increase.
──Agricultural machinery, internal combustion engine castings will continue to have a steady growth in production to 2000 is expected to produce more than 2 million tons.
──Machine tools, valves, hydraulic castings production will also have some growth, due to the application of resin sand, the export of such castings will increase. Machine tool castings accounted for the proportion of all casting weight may still be about 7%.
(3) from the development of key host products on the various types of casting alloy demand analysis
1) cast iron production continues to grow, but the proportion of the total casting output is still maintained at about 80% to 82%, the proportion of the composition of its internal will produce a large change.
── Ductile iron parts due to the sharp increase in automobile production and nearly 10 sets of centrifugal team ink cast iron pipe production line successively put into production, as well as it further replaces part of the cast steel and malleable cast iron parts and a substantial increase, is expected to 2000, China's team ink cast iron parts accounted for the proportion of more than 15%, the annual output of 2 million tons.
---Malleable cast iron parts in the pipe joints, fasteners and line fittings and other products still have a certain market, but because it is in the automotive industry with a sharp decline in the amount of decline is large. It is expected that by 2000, its proportion will fall to 2% to 3%, the annual output of 300,000 to 400,000 tons.
── Gray cast iron parts due to several major products, such as automobiles, diesel engines, tractors, machine tools, a variety of professional machines are still a large number of applications, its output will continue to grow. Expected to 2000, the annual output of 9 million tons, it accounts for the weight of all castings will be slightly reduced in the proportion of about 65%.
2) non-ferrous alloy castings production and the proportion of a larger increase.
──As a result of the next 5 to 10 years China's small cars, motorcycles and leisure office supplies production increased rapidly, China's aluminum alloy castings and aluminum, zinc alloy die casting production will increase substantially. It is expected that by 2000, aluminum alloy castings production is likely to reach about 800,000 tons, accounting for 6% of the total output of castings, due to the limitations of non-ferrous production, the growth rate will also be constrained.
──Copper alloy castings production change little, the proportion will decline.
3) the annual output of steel castings will decline, about 1.2 million tons or so, it will be a slight decline in the proportion of all castings, but which the demand for alloy castings will further increase, so that it accounted for the proportion of all castings rose to 25% to 30%.
(4) international market demand analysis
In recent years, the world's annual output of castings sign of a stable period, generally in the 70-75 million tons, of which ductile iron castings and aluminum alloy castings to a higher rate of growth, while the general grey cast iron parts, malleable cast iron parts and cast steel parts have declined. Due to the impact of energy labor prices and environmental factors, the future casting production in the western industrialized countries will gradually reduce the general castings to developing countries, but at the same time will be exported to developing countries with high value-added, high technology content of high-quality castings. Such as 1990~1993 casting exports in China by an average annual growth rate of 15%, to 2000, China's casting exports may reach 1 million tons, more than 1 times the present growth.
1.3 revitalization goals
(1) revitalization of the overall goal
Can be envisioned in fifteen years or a little more time to fundamentally change the backwardness of China's casting production, and strive to basically meet the country's pillar industries - machinery industry, automobile industry and high technology industries on the demand for high-quality castings, as well as the national economy, infrastructure and people's lives. Demand, so that the overall technical level of China's foundry industry close to the world level.
Before 2000 for the first stage of revitalization. In accelerating the digestion and absorption of the introduction of technology and equipment at the same time, combined with China's specific production conditions and resources, and actively research and development of casting new processes, new materials, new technologies and new equipment, and effectively address the commercialization of casting raw and auxiliary materials, so that their quality and variety of casting technology to meet the requirements of the development of the formation of a number of backbone foundry production enterprises in the international market with competitiveness. Improve the quality and reliability of domestic casting machinery and process equipment to promote China's casting production of high quality, low consumption, high efficiency, less pollution, to revitalize the general objective of laying the foundation.
2001 to 2010 for the revitalization of the second phase. The main casting product performance, quality and reliability to reach the international level at the time, in China to form a more complete supply system of raw and auxiliary materials, as well as independently developed casting machinery and process equipment system.
(2) recent goals
It is expected that by 2000, China's casting output will reach 13.5 million tons. The main contradiction is to improve the quality of castings grade, technical and economic benefits, as well as to solve the working conditions and environmental pollution. Strive "Ninth Five-Year Plan" or a longer period of time through market competition, survival of the fittest, deepen institutional reform and macro-control, so that China's foundry gradually adjusted to a more reasonable level, the formation of about 6,000 or so plants, the number of employees for the industry's basic team of 60 ~ 800,000 people, and to make 1/4 of them to become a key foundry! To achieve economies of scale. These key foundries in the 10% (about 150) to become the backbone of the industry, respectively, to reach or close to the industrialized countries in the late 80's and early 90's of the level of production technology; 90% (about 1,400) of the key foundries to reach the level of industrialized countries in the 80's. The key foundries in the 80's, the level of the industry.
1.4 Recent scale of economic production development goals
By product type production refers to the different ways, all types of castings of the backbone of the foundry's scale of economic production and development goals are:
1) high-volume production of automobiles, internal combustion engines, tractor castings and cast iron pipe, the scale of the economy of batch size of 15,000 to 20,000 tons / year? Plant above. Among them, certain large foundries (group companies) and centrifugal ductile iron pipe plant should reach 50,000 tons / year? Plant above. First of all, the car casting industry to be in the casting quality, mechanization and automation, process technology level, personnel quality and environmental quality, etc. in the "Ninth Five-Year Plan" period to further improve the overall level of production to reach the level of industrially developed countries at the end of the 80's level, a part of the level of the early 90's, and has the ability to compete in the international market. Competitiveness in the international market.
2) into mass production of machine tools, valves, railway locomotives and general-purpose special-purpose machinery castings, the scale of the economic batch of 0.7 million tons / year? Plant above. In technology and equipment should vigorously promote resin sand technology, so that such castings within the quality, dimensional accuracy and surface roughness to meet today's international standards, the overall level of production, including the degree of mechanization, to reach the level of industrially developed countries in the early 1990s. Environmental quality in line with national standards, the establishment of an export base for this type of castings.
3) single piece, small batch production of heavy, large-scale mining, power plant, metallurgy and other machinery castings, the scale of the economic batch should be 0.7 million tons / year? Factory above. Process technology and equipment level, environmental quality to reach the level of industrially developed countries in the late 80's and early 90's, can provide high quality and reliable castings for the key equipment of major national engineering projects, and competitive in the international market.
4) mass production of small precision castings (such as hydraulic parts, small compressors and high-tech castings, etc.), should be as centralized as possible according to the process requirements of the production, the scale of the economic batch size should reach 1,000 to 2,000 tons / year? Plant above; investment castings in a variety of relatively centralized specialized production based on efforts to improve the economic scale, to 500 tons / year? Plant above. The application of the then international advanced level of technology, materials and equipment, so that the hydraulic parts of the gross bad quality problems have been completely resolved, the precision and surface roughness of investment castings to reach the international level of similar products. Environmental quality to meet national standards and establish a part of the high value-added castings export base.
5) aluminum alloy castings of the scale of the economic batch should be 500 ~ 1000 tons / year? Factory above. Castings quality and economic efficiency should reach the level of industrial advanced countries in the early 1990s, to meet the needs of automotive, instrumentation and other industries, environmental quality should meet national standards.
(3) Visionary Goals
To 2010, the use of the world's advanced casting technology and equipment suitable for China's national conditions, the formation of a more complete supply system for China's casting of raw and auxiliary materials and the ability to independently develop the casting machinery and process equipment system. Castings in quantity and quality to fully meet the needs of the machinery industry, and some of the medium and high-grade castings for export. Adjustment of foundry points to 5,000 casting enterprises, and make 60% of them (about 3,000) to become a key casting enterprises, of which 30% (about 900) for the backbone of the enterprise, the level of its production technology, casting product performance and environmental protection quality and so on to reach the international level at that time, 70% (about 2,000) to reach the level of industrially developed countries at the end of the 1990s.