Leak-Proof Upper Tundish Nozzle

Abstract

A leak-proof gas injected upper tundish nozzle including a protective can, and a ceramic inner portion disposed within the protective can. The ceramic inner portion may has gas flow pathways therein which have been formed using a sacrificial mold when producing the ceramic inner portion. A gas flow seal is formed on the interior surfaces of the gas flow pathways within the ceramic inner portion. The gas flow seal blocks gas leakage from the gas flow pathways into any cracks in the ceramic inner portion. The gas flow seal is formed of nickel or an alloy of nickel.

What is claimed is: 
     
         1 - 10 . (canceled) 
     
     
         11 . A gas injected upper tundish nozzle, the nozzle comprising:
 a protective can;   a ceramic inner portion disposed within the protective can, the ceramic inner portion having gas flow pathways therein, the gas flow pathways having been formed using a sacrificial mold when producing said ceramic inner portion;   a gas injection port attached to the protective can, the gas injection port allowing for injection of gas through the protective can and into the gas flow pathways within the ceramic inner portion;   a gas flow seal formed on interior surfaces of the gas flow pathways within sthe ceramic inner portion, the gas flow seal blocking gas leakage from the gas flow pathways into any cracks in the ceramic inner portion;   the gas flow seal being formed of nickel or an alloy of nickel.   
     
     
         12 . The gas injected upper tundish nozzle as recited in  claim 11  wherein the gas flow passages include a gas pressure/distribution manifold and individual gas injection channels. 
     
     
         13 . The gas injected upper tundish nozzle as recited in  claim 12  wherein the sacrificial mold includes a proto-manifold and proto-injection channels formed of sacrificial material. 
     
     
         14 . The gas injected upper tundish nozzle as recited in  claim 13  wherein the gas flow seal is formed by depositing nickel or nickel alloy onto the proto-manifold and proto-injection channels by a method selected from the group consisting of electroless plating, nickel foil strip application, sputtering, physical vapor deposition, chemical vapor deposition, plasma deposition, and metal printing. 
     
     
         15 . The gas injected upper tundish nozzle as recited in  claim 14  wherein additional nickel or nickel alloy is deposited into the gas pressure/distribution manifold and individual gas injection channels after the sacrificial mold has been removed from said ceramic inner portion. 
     
     
         16 . The gas injected upper tundish nozzle as recited in  claim 11  wherein the protective can is formed of a metal material. 
     
     
         17 . The gas injected upper tundish nozzle as recited in  claim 16  wherein the protective can is formed of a steel material. 
     
     
         18 . The gas injected upper tundish nozzle as recited in  claim 11  wherein the ceramic inner portion is formed from a refractory material consisting of a ceramic oxide of one or more of aluminum, silicon, magnesium, chromium, or zirconium, or mixtures thereof. 
     
     
         19 . The gas injected upper tundish nozzle as recited in  claim 11  wherein the gas distribution channels have gas outlets to release the gas into steel flowing within the upper tundish nozzle. 
     
     
         20 . The gas injected upper tundish nozzle as recited in  claim 12  wherein the gas flow seal is formed by depositing nickel or nickel alloy into said gas pressure/distribution manifold and individual gas injection channels after the sacrificial mold has been removed from the ceramic inner portion.