A furnace for melting vitrifiable material, in particular glass, employs a submerged burner, the furnace including a wall cooled by a cooling fluid, the face of the wall facing toward the interior of the furnace having, before vitrifiable material is melted in the furnace, an attachment texture for so-called self-crucible devitrified vitrifiable material.

A furnace for melting vitrifiable material has a composable wall structure, formed by modules, each comprising two flat metal panels separated by a gap for the circulation of cooling water.

A furnace for melting vitrifiable material has a composable wall structure, formed by modules, each comprising two flat metal panels separated by a gap for the circulation of cooling water.

A glass sheet of the present invention has a content of Li.sub.2O+Na.sub.2O+K.sub.2O of from 0 mol % to less than 1.0 mol % and a content of B.sub.2O.sub.3 of from 0 mol % to less than 2.0 mol % in a glass composition, has a β-OH value of less than 0.20/mm, and has a thermal shrinkage ratio of 20 ppm or less when increased in temperature from normal temperature at a rate of 5° C./min, kept at a temperature of 500° C. for 1 hour, and decreased in temperature at a rate of 5° C./min.

A refractory article includes a body including a ceramic having an aluminosilicate present in an amount of at least 70 wt % and not greater than 99 wt % for a total weight of the body, and the body further includes a dopant including a Mg-containing oxide compound and a Fe-containing oxide compound, and the dopant is present in an amount within a range including at least 1 wt % and not greater than 12 wt %.

A refractory article includes a body including a ceramic having an aluminosilicate present in an amount of at least 70 wt % and not greater than 99 wt % for a total weight of the body, and the body further includes a dopant including a Mg-containing oxide compound and a Fe-containing oxide compound, and the dopant is present in an amount within a range including at least 1 wt % and not greater than 12 wt %.

A glass element has, per kg of glass, 50 or fewer inclusions having a size of 2 μm to 10 μm. The glass element can be made of borosilicate glass.

A glass article is designed at least in part in the form of a glass tube element including at least one shell which encloses at least one lumen. For at least one light transmission analysis of the glass article, a ratio of an average amplitude transmission factor and a specific amplitude transmission factor is greater than 1.00001.

Provided is a glass substrate having low chargeability. A glass substrate contains, as a glass composition in terms of % by mass, 1.7 to less than 9% B.sub.2O.sub.3, 0.01% or less Li.sub.2O, 0.001 to 0.03% Na.sub.2O, 0.0001 to 0.007% K.sub.2O, 0.0011 to 0.035% Na.sub.2O+K.sub.2O, and more than 0 to 0.4% SnO.sub.2.

An apparatus for transferring molten glass includes a wall including a refractory material and a metal layer provided on an inside of the refractory material, the metal layer coming into contact with the molten glass, and the metal layer being configured to guide the molten glass, the apparatus including a heater including a metal cover protruding to an inside of the wall, the metal cover coming into contact with the molten glass, the heater including a heat generating element electrically insulated from the metal cover, and the heat generating element receiving electric power to radiate heat rays to heat the metal cover from an inside.