METHOD OF MANUFACTURING MULTILAYER SHELL MOLD ACCORDING TO INVESTMENT PATTERNS Russian patent published in 1997 - IPC

FIELD: molding processes. SUBSTANCE: method includes formation of multilayer mold from ceramic suspension with ethylsilicate binder by way of multiple immersion of mold into suspension, dusting each layer with calcined refractory material, drying each layer, melting pattern in hot air and calcining shell. Method is distinguished with that hot air is fed with velocity 10-20 m/s and simultaneously the pattern is treated with dry saturated steam for 2-20 min. After pattern melting is terminated, steam is removed. EFFECT: improved quality of molds due to elimination of fractures when melting pattern in hot air.