REACTION CRUCIBLE FOR ALUMINOTHERMIC WELDING OPERATIONS, HAVING A REFRACTORY SHUTOFF ELEMENT

摘要

A reaction crucible (1) intended for carrying out aluminothermic welding operations is provided with a bottom (20) having an outflow opening (4) and contains a fine-grain aluminothermic mixture. In order to retain the slag (7) formed as a reaction product of the aluminothermic reaction in the reaction crucible (1), there is provided a shutoff element (10), the density of which is greater than that of the slag (7) and less than that of the molten steel (6), wherein the shutoff element (10) is incorporated into said mixture. The shutoff element (10) consists of a shell (11) which surrounds a filling (12) that consists of a metallic solid body, such that the latter does not prevent the steel (6) from flowing out and only comes into operation once the steel (6) has passed out of the reaction crucible and the outflow opening (4) has been closed by the shutoff element (10).