On the whole, developed countries have advanced casting technology, good product quality, high production efficiency, less environmental pollution, and a commercialized series of raw and auxiliary materials. For example, a transnational service system has been established in Europe. Production is generally mechanized, automated and intelligent (computer control and robot operation).
1.Molding materials and casting technology
In the production of important castings, there are high requirements for materials, such as nodular cast iron with P ≯ 0.04% and s ≯ 0.02%, cast steel with P and s ≯ 0.025%. The contents of C and S1 are controlled timely and accurately by thermal analysis technology. The contents of more than a dozen elements are analyzed by direct reading spectrometer in 2-3 minutes with high precision. Advanced nondestructive testing technology is used to effectively control the quality of castings.
Liquid metal filtration technology is widely used. The grade a qualification rate of radiographic inspection of filtered steel castings is increased by 13%, and the tensile strength and elongation of aluminum magnesium alloy are increased by 50% and more than 100% after filtration. EPC technology was successfully used to mass produce complex castings such as automobile 4-cylinder block and cylinder head, with a productivity of 180 type / hour. C a D / C a m / RPM technology is adopted in process design and die processing; In the specialized and complete preparation of casting machinery, CIM s technology was adopted. In the whole process of casting production, the technical standards are actively and strictly implemented, and the casting scrap rate is only 2% – 5%; The standard is updated quickly (the standard age is 4-5 years); Certification of 15090000, 15014000, etc. is generally carried out.
2.Casting alloy materials and melting
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. For example, various important components such as automobile driving rod, cylinder block, cylinder liner, piston and connecting rod 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 various important automobile parts made of magnesium alloy is second only to aluminum alloy.
Hot blast cupola, two rows of cupola with large spacing and oxygen enriched air supply are adopted. The electric furnace adopts charge preheating, reduces melting temperature, improves furnace operation rate, reduces furnace cover opening time, strengthens thermal insulation 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 factors such as high labor cost and poor production conditions, robots are widely used. Due to the strict environmental protection law (9 countries stipulate 100-250 mg / m3 for electric furnace dust discharge, 100-100 mg / m3 for cupola dust discharge, 11 countries stipulate 100-100 mg / m3, or 0.25-1.5 K molten iron; 8 countries stipulate 100-250 mg / m3 for sand treatment dust discharge), foundries pay attention to environmental protection technology.
Pay attention to the development and use of Internet technology, and establish their own home pages and sites one after another. E-commerce, remote design and manufacturing, virtual foundry are developing rapidly in the.