Patent № 95580 METHOD OF CENTRIFUGAL CASTING OF MULTILAYER ROLLS AND ROLLERS (the priority from 25.08.2010).
The invention relates to metallurgy, in particular to producing multilayer products. A method of centrifugal casting multilayer rolls and rollers includes application on the inner surface of mold of an insulating coating with a thickness of 2-6 mm, filling of the working layer of alloyed cast iron into molds, which is rotated around a horizontal axis, feed of flux on the free surface of working layer, and when the free surface of alloyed iron active layer reaches the temperature Tsol + 10-20 °C an additional buffer layer is fed making 15-20 % of the volume of working layer, then the mold is stopped and transferred into vertical position, filling the core of cast iron with a temperature of Tl + 110-300 °C for 30-60 seconds at reaching the temperature of the free surface of working layer Tsol - 18-180 °C, at mass flow rate of cast iron, which corresponds to the relation:
where VM.Pour. - mass flow of cast iron, kg/s, m - mass of cast alloyed iron of active layer, kg, TF.S. - temperature of the free surface of alloyed cast iron before pouring the core layer, °C, tPour. – time of casting of core iron within 30-60 s, TPour. - temperature of pouring core iron, °C, K - coefficient taking into account the conditions of heat transfer in the mold, and K = 1.1-1.5. Technical effect: obtaining a strong connection of two alloys of dissimilar chemical composition and even distribution of the hardness of the working layer with a minimal decline in depth.