The hottest new development trend of new foundry t

In the face of the unprecedented high-speed development of global information and technology, and the high-speed improvement of the modernization level of machinery manufacturing industry, especially equipment manufacturing industry, China's foundry industry (here only the situation of the mainland, excluding Taiwan, Hong Kong and Macao) should clearly understand its historical responsibility and the realistic gap with developed countries, and boldly make use of the latest achievements of human civilization, Recognize the truth that "only by realizing high-tech can we keep up with the pace of the times", grasp the development trend of modern casting technology tactfully, rationally adopt advanced and applicable technology, wisely implement the strategy of sustainable development, based on reality and have a long-term vision, and lay a solid foundation for the process of China's modern industrial civilization with the fruitful achievements of revitalizing and developing China's casting industry

1. The development status of foundry technology in developed countries

developed countries generally have advanced foundry technology, good product quality, high production efficiency, less environmental pollution, and a commercialized and serialized supply of raw and auxiliary materials. For example, a transnational service system has been established in Europe. Production is generally mechanized, free from glass fiber toughness differential and intelligent (computer control, robot operation)

cast iron smelting uses a large, efficient, dedusting, microcomputer measurement and control, external hot air supply, unlined water-cooling continuous operation cupola, which generally uses foundry coke. Cupola or electric furnace and cupola are combined for smelting, and nitrogen continuous desulfurization or ladle desulfurization is used to make the sulfur content in molten iron reach below 0.01%; AOD, VOD and other equipment are often used for smelting alloy steel refining, so that h, O, N in molten steel can reach several or dozens of levels

in the production of important castings, there are high requirements for materials, such as ductile iron requires P ≯ 0.04%, s ≯ 0.02%, and cast steel requires P and s ≯ 0.025%. Thermal analysis technology is used to accurately control the content of C and Si in time, and direct reading spectrometer is used to analyze the content of more than a dozen elements in 2~3 minutes with high precision. C and S analysis and regulation can accurately control the content of C and s of ultra-low carbon stainless steel, and advanced nondestructive testing technology is used to effectively control the quality of castings

liquid metal filtration technology is widely used, and the filter can adapt to high temperature, such as cobalt based, nickel based alloys and stainless steel liquid filtration. The grade a qualification rate of radiographic inspection of filtered steel castings is increased by 13 percentage points. After filtration, the tensile strength of aluminum magnesium alloy is increased by 50%, and the elongation can immediately increase the repair rate of the removed part by more than 100%

the treatment technology of alloy cored wire is widely used, which makes the process of nodular iron, vermicular iron and inoculated cast iron stable, the yield of alloy elements high, and the treatment process pollution-free, and realizes microcomputer automatic control

aluminum matrix composites are widely valued for their superior performance and are increasingly turning to industrial scale applications, such as automobile drive rods, cylinder blocks, cylinder liners, pistons, connecting rods and other important components can be made of aluminum matrix composites, and have been applied in advanced racing cars; In the process of the development of automobile to lightweight, the amount of making various important automobile parts with magnesium alloy materials has been second only to aluminum alloy

hot blast cupola, two rows of cupola with large spacing and oxygen enriched air supply are used. The electric furnace adopts charge preheating, reduces melting temperature, improves furnace operation rate, reduces furnace cover opening time, strengthens heat preservation and implements microcomputer control to optimize smelting process. Small riser and non riser casting are widely used in the production of nodular iron castings. Steel castings adopt insulation risers and insulation subsidies, and the process yield is increased from 60% to 80%. Considering the high labor cost and poor production conditions, robots are widely used. Due to the strict environmental protection law (the dust discharge of electric furnace is mg/m3 in 9 countries, the dust discharge of cupola is mg/m3 in 11 countries, or 0..5kg/t molten iron; the dust discharge of sand treatment is mg/m3 in 8 countries.), Foundries all attach importance to environmental protection technology

in the production of large quantities of small and medium-sized castings, the high-density static pressure, injection molding or air impact molding mechanization and automatic high-efficiency assembly line green sand molding process controlled by microcomputer are mostly used. The sand treatment adopts high-efficiency continuous sand mixer and artificial intelligent sand control expert system. The resin sand hot, warm core box method and cold core box method are widely used in the core making process. The shell making process of investment casting generally uses silica sol and ethyl silicate as binder

use automatic die-casting machine to produce cast aluminum cylinder block and cylinder head; Several iron-based alloy low-pressure casting production lines have been built. Special steel castings are produced by differential pressure casting. Centrifugal ductile iron pipes with various diameters account for more than 95% of the total cast iron pipes, and ductile iron pipes account for 30% - 50% of the annual output of ductile iron

EPC technology has been successfully used to mass produce complex castings such as automobile 4-cylinder block and cylinder head, with a productivity of 180 models/hour. Cad/cam/rpm technology is adopted in process design and mold processing; In casting machinery 3. Specialization and complete sets with indication accuracy of ± 1%, the company has produced about 5000 square meters of innovative composite materials for the automotive industry, electrical and sports industries, and began to adopt CIMS technology

in the whole process of casting production, technical standards are actively and strictly implemented, and the casting scrap rate is only 2%-5%; The standard is updated quickly (standard age years); Generally carry out ISO9000, ISO14000 and other certification

pay attention to the development and use of Internet technology, and set up their own home pages and sites. E-commerce, remote design and manufacturing, and virtual foundry are developing rapidly in the foundry industry

2. The development status of foundry technology in China

on the whole, the academic research in the field of foundry in China is not backward, and many research results are at the international advanced level, but few are translated into real productivity. Domestic foundry production technology is only limited to a few backbone enterprises. The overall technical level of the industry is backward, the casting quality is low, the consumption of materials and energy is high, the economic benefit is poor, the working conditions are poor, and the pollution is serious. Specifically, the appearance is still processed by hand or simple machinery; The socialization, specialization and commercialization of the production and supply of casting raw and auxiliary materials are far from meeting the needs of the development of new processes and technologies in terms of variety and quality; The production level and quality of casting alloy materials are low; Backward production management; Process design is mostly based on personal experience, and the application of computer technology is less; Poor basic conditions such as casting technology and equipment; Manual operation ratio of production process