Methods and apparatus for producing fibers from igneous rock, including basalt include heating igneous rock by electrical conductive coils to achieve an homogenous melt and forming homogenous fibers from the melt.

Methods and apparatus for producing fibers from igneous rock, including basalt include heating igneous rock by electrical conductive coils to achieve an homogenous melt and forming homogenous fibers from the melt.

A holding member is used in a glass manufacturing apparatus that cools down a glass raw material that has been levitated by gas and has been heated and melted, and manufactures glass. The holding member includes a gas injection surface that includes a plurality of injection ports from which the gas is injected. The gas injection surface includes a first region and a second region, the first region including first injection ports that are some injection ports of the plurality of injection ports, the second region including second injection ports that are different from the first injection ports from among the plurality of injection ports. The first region is located inside the second region, when the gas injection surface is viewed from the top. An area of the injection ports per unit area of the first region is smaller than the area of the injection ports per the unit area of the second region. The area of the injection ports per the unit area of the first region is a ratio of the total of cross-sectional areas of the first injection ports to the area of the first region when the gas injection surface is viewed from the top. The area of the injection ports per the unit area of the second region is the ratio of the total of cross-sectional areas of the second injection ports to the area of the second region when the gas injection surface is viewed from the top.

A holding member is used in a glass manufacturing apparatus that cools down a glass raw material that has been levitated by gas and has been heated and melted, and manufactures glass. The holding member includes a gas injection surface that includes a plurality of injection ports from which the gas is injected. The gas injection surface includes a first region and a second region, the first region including first injection ports that are some injection ports of the plurality of injection ports, the second region including second injection ports that are different from the first injection ports from among the plurality of injection ports. The first region is located inside the second region, when the gas injection surface is viewed from the top. An area of the injection ports per unit area of the first region is smaller than the area of the injection ports per the unit area of the second region. The area of the injection ports per the unit area of the first region is a ratio of the total of cross-sectional areas of the first injection ports to the area of the first region when the gas injection surface is viewed from the top. The area of the injection ports per the unit area of the second region is the ratio of the total of cross-sectional areas of the second injection ports to the area of the second region when the gas injection surface is viewed from the top.

An apparatus for manufacturing glass includes a furnace. A doghouse of the furnace receives and melts solid-glass forming material using one or more submerged combustion burners. An elongated tank positioned downstream of the doghouse includes a melting chamber, a refining chamber, and a thermal conditioning. The melting chamber has in inlet through which molten glass is received from the doghouse. The refining chamber is positioned downstream of the melting chamber and receives molten glass from the melting chamber. The thermal conditioning chamber is positioned downstream of the refining chamber and receives molten glass from the refining chamber. Additionally, the thermal conditioning chamber delivers molten glass to a glass forming machine.

An apparatus for manufacturing glass includes a furnace. A doghouse of the furnace receives and melts solid-glass forming material using one or more submerged combustion burners. An elongated tank positioned downstream of the doghouse includes a melting chamber, a refining chamber, and a thermal conditioning. The melting chamber has in inlet through which molten glass is received from the doghouse. The refining chamber is positioned downstream of the melting chamber and receives molten glass from the melting chamber. The thermal conditioning chamber is positioned downstream of the refining chamber and receives molten glass from the refining chamber. Additionally, the thermal conditioning chamber delivers molten glass to a glass forming machine.

A process for treating a fused refractory product including more than 10% by mass of ZrO.sub.2, or “base product.” The process includes heating at least a portion of the surface of the product, so as to melt ZrO.sub.2 crystals in a superficial region extending to a depth of less than 2000 μm. The process includes cooling the molten superficial region obtained in the preceding step so as to obtain a protective layer.

A process for treating a fused refractory product including more than 10% by mass of ZrO.sub.2, or “base product.” The process includes heating at least a portion of the surface of the product, so as to melt ZrO.sub.2 crystals in a superficial region extending to a depth of less than 2000 μm. The process includes cooling the molten superficial region obtained in the preceding step so as to obtain a protective layer.

Methods and apparatus for producing fibers from igneous rock, including basalt include heating igneous rock by electrical conductive coils to achieve an homogenous melt and forming homogenous fibers from the melt.

Methods and apparatus for producing fibers from igneous rock, including basalt include heating igneous rock by electrical conductive coils to achieve an homogenous melt and forming homogenous fibers from the melt.