Alan Chi Engel

US Patent:

54313740, Jul 11, 1995

Filed:

Oct 29, 1993

Appl. No.:

8/143112

Inventors:

Dominique Janssen - Tyler TX
Jon Bell - Whitehouse TX
Dave Moore - Rantoul IL
Bruce Winter - Mahomet IL
George Sundy - Mahomet IL
Alan J. Engel - Sewickley PA

Assignee:

Vesuvius Crucible Company - Wilmington DE

International Classification:

B22D 4142
B22D 4158

US Classification:

266 45

Abstract:

A unitized nozzle and top plate assembly for use in a slide gate valve is disclosed which comprises a nozzle having porous, gas permeable walls, a top plate having an opening through its thickness for regulating a flow of molten metal, such as steel, and a recess circumscribing the opening for receiving and securing the discharge end of the nozzle to the top plate. The depth of the recess is at least 50%, and preferably 70-80% of the thickness of the top plate in order to minimize the contact between molten metal and the surface of the top plate opening, which in turn reduces the amount of flow-obstructing alumina deposits which accumulate in this area of the slide gate valve. To prevent leaks from occurring in the system supplying pressurized argon through the porous nozzle walls, the gas coupling that is normally welded directly to the steel can surrounding the nozzle is instead mounted on the end of a steel pipe connected to the can. The thermal resistance of the steel pipe substantially reduces the temperature that the coupling is exposed to. The invention also encompasses a method for facilitating the assembly and maintenance of the slide gate valve by the use of the unitized nozzle and top plate in lieu of the in situ mounting of such a nozzle on a top plate already installed in such a valve.