Method of heat retention in a blind riser

摘要

A method of the heat-retention in a blind riser in metal casting by using a sand mould, characterized in that an exothermic moulded composition is arranged in a drag holding cavity below a blind riser in the cope of the mould or in the neighborhood of the blind riser before the melt is poured, and thereafter the melt is poured to cause the exothermic moulded composition to float up into the blind riser to retain heat therein.