Patent EA-001327-B1 (EA)
Title: Slagline sleeve for submerged entry nozzle, method of manufacturing and composition thereof
Inventor: HOOVER DONALD B
IPC: C04B35/66
Filed: 1997-07-08
Abstract: 1. A composition for forming a slagline sleeve which comprises zirconium oxide, graphite and resin binder capable of forming a resite during a curing reaction which liberates water, said zirconium oxide optionally containing a stabilizing amount of CaO or MgO within the crystalline structure thereof; wherein the improvement comprises an effective amount of CaO containing powder incorporated in said composition to counteract contractile forces which develop when said resin is cured to form said resite; said CaO containing powder being separate and distinct from said optional CaO or MgO contained within the crystalline structure of said zirconium oxide. 2. The composition of claim 1 wherein said CaO containing powder is selected from the group consisting of dead burned lime and doloma. 3. The composition of claim 2 which comprises 80-90% by weight of zirconium oxide partially stabilized with CaO or MgO, 10-20% graphite, 5-10% antioxidant, 10-20% phenolic resin solution containing 40-60% by weight of phenolic resin dissolved therein, and about 5% doloma. 4. The composition of claim 3 which comprises about 12% graphite, about 83% zirconium oxide, about 5% doloma, and about 11% phenolic resin solution containing furfuraldehyde solvent containing about 50% by weight of said phenolic resin dissolved therein. 5. A method for making a nozzle for pouring molten metal, said nozzle comprising a body portion and a slagline sleeve portion attached thereto; said body portion having a shape which includes an exterior surface and an inner surface region wherein said inner surface region defines a bore extending therethrough for the passage of molten metal; said slagline sleeve portion being located around at least a circumferential portion of said exterior surface for contact with a slag layer in a continuous casting mold; said method comprising forming said body portion by molding a first mixture containing resin binder, graphite and metal oxide refractory particles, into the shape of said body portion and then curing the resin of said first mixture; and forming a second mixture which comprises zirconium oxide, graphite and resin binder capable of forming a resite during a curing reaction which liberates water, coating said second mixture onto at least a circumferential portion of said exterior surface and then curing said resin of said second mixture to form a resite, said zirconium oxide optionally containing a stabilizing amount of CaO or MgO within the crystalline structure thereof; wherein the improvement comprises the further inclusion of an effective amount of CaO containing powder in said second mixture to counteract contractile forces which deveiop when said resin of said second mixture is cured to form said resite, said CaO containing powder being separate and distinct from said optional CaO or MgO contained within the crystalline structure of said zirconium oxide. 6. The method of claim 5 wherein said first mixture comprises doloma, graphite and resin binder. 7. The method of claim 6 wherein said CaO containing powder is selected from the group consisting of dead burned lime and doloma. 8. The method of claim 7 wherein said second mixture comprises 80-90% by weight of zirconium oxide partially stabilized with CaO or MgO, 10-20% graphite, 5-10% antioxidant, 10-20% by weight of a phenolic resin solution containing 40-60% by weight of phenolic resin dissolved therein, and about 5% by weight of doloma. 9. The method of claim 8 wherein said second mixture comprises about 12% by weight graphite, about 83% by weight zirconium oxide, about 5% by weight doloma and about 11 % by weight of phenolic resin solution containing furfuraldehyde solvent containing about 50% by weight of said phenolic resin dissolved therein. 10. The nozzle comprising a body portion and a slagline sleeve portion attached thereto, said body portion having a shape which includes an exterior surface and an inner surface region wherein said inner surface region defines a bore extending therethrough for the passage of molten metal, said slagline sleeve portion being located around at least a circumferential portion of said exterior surface for contact with a slag layer in a continuous casting mold, said body portion is formed by molding a first mixture containing resin binder, graphite and metal oxide refractory particles, into the shape of said body portion and then curing the resin of said first mixture, and forming a second mixture which comprises zirconium oxide, graphite and resin binder capable of forming a resite during a curing reaction which liberates water, coating said second mixture onto at least a circumferential portion of said exterior surface and then curing said resin of said second mixture to form a resite, said zirconium oxide optionally containing a stabilizing amount of CaO or MgO within the crystalline structure thereof, wherein the improvement comprises the further inclusion of an effective amount of CaO containing powder in said second mixture to counteract contractile forces which deveiop when said resin of said second mixture is cured to form said resite, said CaO containing powder being separate and distinct from said optional CaO or MgO contained within the crystalline structure of said zirconium oxide. 11. The nozzle of claim 10 wherein said first mixture comprises doloma, graphite and resin binder. 12. The nozzle of claim 11 wherein said CaO containing powder is selected from the group consisting of dead burned lime and doloma. 13. The nozzle of claim 12 wherein said second mixture comprises 80-90% by weight of zirconium oxide partially stabilized with CaO or MgO, 10-20% graphite, 5-10% antioxidant, 10-20% by weight of a phenolic resin solution containing 40-60% by weight of phenolic resin dissolved therein, and about 5% by weight of doloma. 14. The nozzle of claim 13 wherein said second mixture comprises about 12% by weight graphite, about 83% by weight zirconium oxide, about 5% by weight doloma and about 11 % by weight of phenolic resin solution containing furfuraldehyde solvent containing about 50% by weight of said phenolic resin dissolved therein.made by the process of claim 8. 15. The nozzle of claim 10 which has been subjected to carbonizing conditions whereby the resin of said first and second mixtures is carbonized thus forming a carbon matrix in said body portion and said slagline sleeve portion.