Refractory nozzle

Abstract

A refractory nozzle is provided for arrangement in or on a wall of a metallurgical crucible, particularly for steel melts, having a discharge duct surrounding a flow passage, wherein the discharge duct has a surface delimiting the flow passage and an outer housing. In order to improve the known solutions of the prior art, one embodiment of the nozzle is characterized by the discharge duct having an upper part and a lower part with the lower part being fixed in or on the upper part, wherein the surface of the upper part delimiting the flow passage is made of a different material than the surface of the lower part delimiting the flow passage. In a second embodiment the nozzle is characterized by the discharge duct having an upper part and a lower part with the lower part being fixed on or in the upper part, wherein the diameter of the flow passage in the upper part is greater than the diameter in the lower part.

1 . A refractory nozzle for arrangement in or on a wall of a metallurgical crucible, particularly for steel melts, the nozzle comprising a discharge duct surrounding a flow passage, the discharge duct having a surface delimiting the flow passage and an outer housing ( 4 ), the discharge duct having an upper part ( 10 ) and a lower part ( 6 ) with the lower part ( 6 ) being fixed on or in the upper part ( 10 ), wherein the surface of the upper part ( 10 ) delimiting the flow passage ( 2 ) is made of a different material than the surface of the lower part ( 6 ) delimiting the flow passage ( 2 ), and wherein the material of the lower part ( 6 ) delimiting the flow passage ( 2 ) is at least partially surrounded by a heater ( 7 ).  
   
   
       2 . The refractory nozzle according to  claim 1 , wherein a thermally highly insulating material is arranged between the heater ( 7 ) and the housing ( 4 ).  
   
   
       3 . The refractory nozzle according to  claim 1 , wherein a diameter of the flow passage ( 2 ) in the upper part ( 10 ) is larger than a diameter of the flow passage ( 2 ) in the lower part ( 6 ).  
   
   
       4 . A refractory nozzle for arrangement in or on a wall of a metallurgical crucible, particularly for steel melts, the nozzle comprising a discharge duct surrounding a flow passage, the discharge duct having a surface delimiting the flow passage and an outer housing ( 4 ), the discharge duct having an upper part ( 10 ) and a lowest part ( 6 ) with the lowest part ( 6 ) being fixed on or in the upper part ( 10 ), wherein the surface of the upper part ( 10 ) delimiting the flow passage ( 2 ) is made of a different material than the surface of the lowest part ( 6 ) delimiting the flow passage ( 2 ), and wherein the material of the lowest part ( 6 ) delimiting the flow passage ( 2 ) is at least partially surrounded by a heater ( 7 ).  
   
   
       5 . The refractory nozzle according to  claim 4 , wherein a thermally highly insulating material is arranged between the heater ( 7 ) and the housing ( 4 ).  
   
   
       6 . The refractory nozzle according to  claim 4 , wherein a diameter of the flow passage ( 2 ) in the upper part ( 10 ) is larger than a diameter of the flow passage ( 2 ) in the lowest part ( 6 ).