PROCESS AND INSTALLATION FOR CASTING LARGE-SIZED REVOLVING PARTS WITH IMPOSED CHARACTERISTICS

The invention relates to a process for preparing a moulding sand meant for casting large-sized revolving parts by non-conventional processes and to an installation allowing the preparation of a multilayer moulding sand. According to the invention, the process consists in successively depositing some layers with a thickness in the range of 1.3-2 cm comprising SIOsand with a grain size ranging between 0.002 and 0.15 mm and chromite sand, respectively, comprising 55% CrOand 21% FeOwith a grain size ranging between 0.01-0.1 mm, by means of an adjustable strickle under the influence of a vibration ranging from 30 to 50 Hz, wherein there are introduced the classic ingredients for the moulding sands with suitable grain size. According to the invention, the installation comprises a vibrating platform (1) which is vibrated with the system comprising a motor (2), an eccentric table (3), a damping unit (4) whereon there is located the metal shuttering (5) with a central core (6) placed therein, which creates the casting cavity (7) wherein the molten alloy reaches by means of the pouring gate (8).