Klymenko S. Technology of casting heads and engine blocks made of gray and ductile cast iron on gasified patterns with forced cooling molds of refrigerants.

Dissertation is devoted to the development of technologies for production of castings heads and engine blocks made of gray and ductile cast iron on gasified patterns with adjustable mold cooling refrigerants. With the application of known and new techniques are studied heat transfer processes between the liquid metal, casting, which solidifies and cools in vacuum sand mold with differentiated thermal characteristics for targeted intensive action of a liquid and gas, as well as dynamic movements of loose filler shapes. This is main fact in the regulation of which is developed by the novelty varieties Lost Foam Casting Process with evacuated quartz sand molds. Analysis of all series of experiments to control the intensity of heat exchange between the liquid metal solidifies and cools the sand mold casting showed that in all cases the application of the developed methods of regulation in the mold of heat exchange processes can increase their intensity is 1.3 - 1.7 times. The studies used the original alpha-calorimeter for thermal analysis of the interaction of metal casting and mold with simultaneous computer display and graphical interpretation of temperature fields and the casting mold. The original method to determine the influence of the dynamic movement of the unbound mold of the refractory metal solidifying on cooling and casting using a vibrating table with variable frequency and amplitude, as well as cast sample with elements of different thicknesses. It is shown that the gasification in the form of expanded polystyrene pattern accelerates cooling of the molten metal and causing it to hardening, as compared with the molding in a cavity mold. The result of the research structures and physico-mechanical properties of gray and ductile cast iron obtained from the evacuated forms with different heat storage capacity, as well as an increase in the convective component of the cooling process of cast metal, steel data to justify and the laws of the relevant changes in the structure molten metal predetermined prediction performance cast complex structures of variable section, in particular, heads and engine blocks. Created new ways of controlled cooling of castings in sand mold for inventions, technological schemes introduced in production of castings Lost Foam Casting process for the production of castings weighing 25 - 750 kg. The technology implemented in the production of cast designs motor group in the first place, head, cylinder block, low metal consumption and increased service life of gray and ductile cast iron. New technology using specific gray and ductile iron castings possible to reduce the weight by 25 - 30% and 40 - 45%, respectively, and reduce production costs by 4.5 - 7.0 thousand Grn. / Ton casting.