Electromagnetic valve for controlling the flow of molten, magnetic material

An electromagnetic valve for controlling the flow of molten, magnetic material comprising:

• a) a housing;
• b) a composite nozzle mounted within said housing, said composite nozzle being comprised of:
• i) an inner sleeve composed of an erosion resistant refractory ceramic material, said inner sleeve having a wall thickness in the range of about 3 to 7 mm;
• ii) an outer shell composed of a refractory ceramic material, said outer shell having a wall thickness in the range of about 10 to 25 mm;
• and
• iii) a layer of heat-setting compressible refractory material sandwiched between said inner sleeve and said outer shell, said heat-setting compressible refractory material having a thickness in the range of about 1 to 2 mm, wherein said heat-setting compressible refractory material is compressible through substantially the entire range of about 70.degree. F. to about 2600.degree. F. and has a setting temperature that lies within the range of about 2600.degree. F. to about 2700.degree. F.;
• c) an induction coil mounted circumferentially around said composite nozzle in such an arrangement as to allow an electromagnetic field generated by said induction coil to slow the passage of said magnetic material through said composite nozzle;
• and
• d) means for applying an alternating electric current to said induction coil.

An electromagnetic valve for controlling the flow of molten, magnetic material comprising:

• a) a housing;
• b) a nozzle mounted within said housing, said nozzle being comprised of:
• i) a refractory inner sleeve composed of zirconia ceramic having a wall thickness in the range of about 3 to 7 mm, wherein said refractory inner sleeve is subject to destructive mechanical forces due to thermal gradients present within said refractory nozzle;
• ii) a refractory outer shell composed of mullite ceramic having a wall thickness in the range of about 10 to 25 mm;
• and
• iii) a layer of heat-setting compressible refractory material composed of unset, high alumina, heat-setting mortar having a thickness in the range of about 1 to 2 mm, wherein said heat-setting compressible refractory material is sandwiched between said refractory inner sleeve and said refractory outer shell, is compressible through substantially the entire range of about 70.degree. F. to about 2600.degree. F. and has a setting temperature that lies within the range of about 2600.degree. F. to about 2700.degree. F.;
• c) an induction coil mounted circumferentially around said nozzle in such an arrangement as to allow an electromagnetic field generated by said induction coil to slow the passage of said magnetic material through said nozzle;
• and
• d) means for applying an alternating electric current to said induction coil.

An electromagnetic valve for controlling the flow of molten steel comprising:

• a) a housing;
• b) a nozzle mounted within said housing, said nozzle being comprised of:
• i) a refractory inner sleeve composed of zirconia ceramic, said refractory inner sleeve having a wall thickness in the range of about 3 to 7 mm, said inner sleeve also having a wall thickness that does not vary by more than +/- 5 mm along the entirety of said inner sleeve;
• ii) a refractory outer shell composed of mullite ceramic, said refractory outer shell having a wall thickness in the range of about 10 to 25 mm;
• and
• iii) a layer of heat-setting compressible refractory material sandwiched between said refractory inner sleeve and said refractory outer shell, wherein said heat-setting compressible refractory material is composed of unset, high alumina, heat-setting mortar having a thickness in the range of about 1 to 2 mm, is compressible through substantially the entire range of about 70.degree. F. to about 2600.degree. F. and has a setting temperature that lies within the range of about 2600.degree. F. to about 2700.degree. F.;
• c) an induction coil mounted circumferentially around said nozzle in such an arrangement as to allow an electromagnetic field generated by said induction coil to slow the passage of said molten steel through said nozzle;
• and
• d) means for applying an alternating electric current to said induction coil.

An electromagnetic valve for controlling the flow of molten, magnetic material comprising:

• a) a housing;
• b) a nozzle mounted within said housing, said nozzle being comprised of:
• i) a refractory inner sleeve composed of zirconia ceramic having a wall thickness in the range of about 3 to 7 mm;
• ii) a refractory outer shell composed of mullite ceramic having a wall thickness in the range of about 10 to 25 mm;
• and
• iii) a layer of heat-setting compressible refractory material composed of unset, high alumina, heat-setting mortar having a thickness in the range of about 1 to 2 mm, wherein said heat-setting compressible refractory material is sandwiched between said refractory inner sleeve and said refractory outer shell, is compressible through substantially the entire range of about 70.degree. F. to about 2600.degree. F. and has a setting temperature that lies within the range of about 2600.degree. F. to about 2700.degree. F.;
• c) an induction coil mounted circumferentially around said nozzle in such an arrangement as to allow an electromagnetic field generated by said induction coil to slow the passage of said magnetic material through said nozzle;
• and
• d) means for applying an alternating electric current to said induction coil.

An electromagnetic valve for controlling the flow of molten, magnetic material comprising:

• a) a housing;
• b) a nozzle mounted within said housing, said nozzle being comprised of:
• i) a refractory inner sleeve composed of zirconia ceramic having both an inner and outer surface;
• ii) a layer of heat-setting compressible refractory material composed of unset, high alumina, heat-setting mortar surrounding and in contact with said refractory inner sleeve on the outer surface of said sleeve, wherein said heat-setting compressible refractory material is compressible through substantially the entire range of about 70.degree. F. to about 2600.degree. F. and has a setting temperature that lies within the range of about 2600.degree. F. to about 2700.degree. F.;
• and
• iii) a refractory outer shell composed of mullite ceramic and having both an inner and outer surface, said outer shell surrounding said layer of heat-setting compressible refractory material, whereby the inner surface of said shell is in substantial contact with said layer of compressible refractory material;
• c) an induction coil mounted circumferentially around said nozzle in such an arrangement as to allow an electromagnetic field generated by said induction coil to slow the passage of said magnetic material through said nozzle;
• and
• d) means for applying an alternating electric current to said induction coil.

A process of controlling the flow of molten, magnetic material in a continuous casting system comprising the steps of:

• a) first applying an alternating electric current to an induction coil mounted within an electromagnetic valve to initiate gravitational flow of liquid magnetic material through said electromagnetic valve;
• said electromagnetic valve comprising:
• i) a housing;
• ii) a nozzle mounted within said housing, said nozzle being comprised of:
• 1) a refractory inner sleeve composed of an erosion resistant ceramic material;
• 2) a refractory outer shell;
• and
• 3) a layer of heat-setting compressible refractory material sandwiched between said refractory inner sleeve and said refractory outer shell, wherein said heat-setting compressible refractory material is compressible through substantially the entire range of about 70.degree. F. to about 2600.degree. F. and has a setting temperature that lies within the range of about 2600.degree. F. to about 2700.degree. F.;
• iii) an induction coil mounted circumferentially around said nozzle in such an arrangement as to allow an electromagnetic field generated by said induction coil to slow the passage of said magnetic material through said nozzle;
• and
• iv) means for applying an alternating electric current to said induction coil;
• and
• b) then varying the electric current applied to said induction coil to regulate the flow of said magnetic material through said nozzle.

A process of controlling the flow of molten steel in a continuous casting system comprising the steps of:

• a) first pouring molten steel into a tundish to initiate gravitational flow of liquid steel through an electromagnetic valve, said electromagnetic valve comprising:
• i) a housing;
• ii) a nozzle mounted within said housing, said nozzle being comprised of:
• 1) a refractory inner sleeve composed of zirconia ceramic, said refractory inner sleeve having a wall thickness in the range of about 3 to 7 mm, said sleeve having a wall thickness that does not vary by more than +/- 5 mm along the entirety of said inner sleeve;
• 2) a refractory outer shell composed of mullite ceramic, said refractory outer shell having a wall thickness in the range of about 10 to 25 mm;
• and
• 3) a layer of heat-setting compressible refractory material sandwiched between said refractory inner sleeve and said refractory outer shell, wherein said heat-setting compressible refractory material is composed of unset, high alumina, heat-setting mortar having a thickness in the range of about 1 to 2 mm, is compressible through substantially the entire range of about 70.degree. F. to about 2600.degree. F. and has a setting temperature that lies within the range of about 2600.degree. F. to about 2700.degree. F.;
• iii) an induction coil mounted circumferentially around said nozzle in such an arrangement as to allow an electromagnetic field generated by said induction coil to slow the passage of said molten steel through said nozzle;
• and
• iv) means for applying an alternating electric current to said induction coil;
• and
• b) then varying the electric current to said induction coil to regulate the flow of said molten steel through said nozzle.

A refractory composite nozzle for use in an electromagnetic valve comprised of:

• a refractory inner sleeve composed of an erosion resistant ceramic material;
• a refractory outer shell;
• and
• a layer of heat-setting compressible refractory material sandwiched between said refractory inner sleeve and said refractory outer shell, wherein said heat-setting compressible refractory material is compressible through substantially the entire range of about 70.degree. F. to about 2600.degree. F. and has a setting temperature that lies within the range of about 2600.degree. F. to about 2700.degree. F.