Improvement Of Casting Product Quality By Introduction Of Middle Frequency Induction Technology

With the development of the manufacturing technology for diesel engines, the requirement to cylinder block, cylinder head comprehensive performance is getting more and more strict, high strength, high durability, good structure evenness, machining performance, high temperature stability, size accuracy have become the basic requirements for cylinder block and cylinder head and iron molten technology plays a decisive role in the casting iron material and the final product. This text illustrates how to use middle frequency induction furnace technology to reform the existing iron melting conditions and settle the problems of iron molten non-stable, which directly affect quality of casting parts and diesel engines.This text includes the purpose of the technology reformation to the existing foundry melting process, the advantages of the reformation plan for the cupola furnace and middle –frequency furnace to realize the double furnaces combination work, how to design the process parameters for the middle – frequency furnace according to our company foundry process requirements. The text illustrates the characteristic of the middle - frequency induction furnace and the advanced technology which mainly from the four aspects of middle-frequency power supply, melting management computer system, furnace body coils and water supply system to state the furnace composition and its operation diagrams. Analyzing the theoretical basis of using parallel inverters in the middle – frequency power supply and the inverters working process as well as the designing basis and mode are given to several main parameters in the middle-frequency power supply.The whole work process of the middle frequency power supply from the commissioning preparation to trial production is described in details, with the accuracy guarantee of the middle-frequency power supply rated power, temperature and frequency control, the iron molten chemical composition adjustment is correct high temperature iron molten is purified, which realized the foundry process for the density structure of the casting parts ,good physical mechanical performance, no defects or less defects. For this reformation our company's diesel engines quality have come to a new level.From the process analysis, equipment study and selection to equipment installation and ready made iron molten, the author experienced the whole series process and made the conclusion as the above, this thesis is the combination of theory and practice.