Abstract: An apparatus for treating molten metal includes a treatment vessel for holding molten metal and a removable cover or hood for the vessel. Sealing means are provided between the cover and the vessel to provide a gas tight treatment zone. The sealing means include mating peripheral flanges on the vessel and cover, with the cover flange having two spaced annular sealing strips for contacting the vessel flange and a metal annular splash protector. These sealing strips include a thermal barrier strip formed of a deformable fibrous refractory material to provide a gas tight, a thermal barrier between the interior of the vessel and the exterior and a metal annular strip upon which the cover is supported on the vessel with the cover flange at a fixed distance above the vessel flange and the thermal barrier strip is compressed therebetween to a controlled degree.

Abstract: An apparatus for treating molten metal includes a treatment vessel for holding molten metal and a removable cover or hood for the vessel. Sealing means are provided between the cover and the vessel to provide a gas tight treatment zone. The sealing means include mating peripheral flanges on the vessel and cover, with the cover flange having two spaced annular sealing strips for contacting the vessel flange and a metal annular splash protector. These sealing strips include a thermal barrier strip formed of a deformable fibrous refractory material to provide a gas tight, a thermal barrier between the interior of the vessel and the exterior and a metal annular strip upon which the cover is supported on the vessel with the cover flange at a fixed distance above the vessel flange and the thermal barrier strip is compressed therebetween to a controlled degree.

Abstract: An apparatus for treating molten metal includes a treatment vessel for holding molten metal and a removable cover or hood for the vessel. Sealing means are provided between the cover and the vessel to provide a gas tight treatment zone. The sealing means include mating peripheral flanges on the vessel and cover, with the cover flange having three spaced annular sealing strips for contacting the vessel flange. These sealing strips include a first outer annular strip formed of an elastomeric material to give an air tight seal between the cover and vessel and a second middle annular strip formed of a deformable fibrous refractory material to provide a thermal barrier between the interior of the vessel and the outer annular strip. A third inner annular strip is a rigid metal strip upon which the cover is supported on the vessel with the cover flange at a fixed distance above the vessel flange and the outer sealing strip and middle sealing strip compressed therebetween to a controlled degree.