Process of molding exothermic compositions

Claim 1

A PROCESS FOR THE PRODUCTION OF FOUNDRY MOLDS EQUIPPED WITH EXOTHERMIC RISER SLEEVES WHICH ARE FORMED IN SITU, PROCESS COMPRISING (1) INSERTING A SLIGHTLY-TAPERED, CYLINDRICAL PLUG INTO THE TOP PORTION OF THE MOLD TO FORM AN ANNULAR SPACE BETWEEN THE PLUG AND THE MOLD, SAID PLUG BEING SUPPORTED ON THE PATTERN; (2) FILLING AND RAMMING THE ANNULAR SPACE WITH MOLD- ING SAND; (3) WITHDRAWING THE PLUG AND INSERTING A SMALLER, SLIGHTLY-TAPERED, CYLINDRICAL PLUG INTO THE CAVITY FROM WHICH THE LARGER PLUG WAS WITHDRAWN TO FORM AN ANNULAR SPACE BETWEEN THE PLUG AND THE WALL OF THE CAVITY, SAID PLUG BEING SUPPORTED ON THE PATTERN; (4) FORMING AN INSULATING SHOULDER BY RAMMING THE LOWER PORTION OF THE ANNULAR SPACE WITH MOLDING SAND; (5) FILLING AND RAMMING THE REMAINDER OF THE ANNULAR SPACE WITH GREEN EXOTHERMIC COMPOSITION; AND (6) WITHDRAWONG THE PLUG TO COMPLETE THE MOLD.