The invention relates to a fiberglass material manufacture method and facility, were in molten glass is converted into fiberglass material via the steps of spinning, drawing, sizing, and collecting, followed by a step of producing a resulting fiberglass material that is then subjected to thermal desizing. The fumes from the melting furnace are used to preheat a combustion reagent from the melting furnace in two steps: a first step in which air is heated via heat exchange with the fumes, and a second step in which the combustion reagent is preheated via heat exchange with the hot air, the air then being used in the step of desizing the fiberglass material.

A thermal insulation product based on mineral wool, characterized in that the fibers have a micronaire of less than 10 l/min, preferably less than 7 l/min and especially between 3 and 6 l/min, and in that the material has a thermal conductivity of less than 31 mW/m.Math.K, especially less than 30 mW/m.Math.K. The parameters for obtaining this product are in particular the pressure of the burner, the rotation speed of the fiberizing spinner and the daily fiber output per spinner orifice.

The invention relates to a thermal insulation product based on mineral wool comprising mineral fibers, the product comprising two main faces and longitudinal and transverse edges perpendicular to the main faces, the product being characterized by the following orientation fractions: a longitudinal orientation fraction greater than or equal to 48%, or even 50%, along an angle of more or less 6? with respect to the plane of the main faces, when the mineral fibers are counted only in a longitudinal cross-section, and a mean orientation fraction greater than or equal to 40%, or even 45%, along an angle of more or less 6? with respect to the plane of the main faces, when the mineral fibers are counted both in a transverse cross-section and in a longitudinal cross-section.

The invention allows the insulating power of a thermal insulation product based on mineral wool to be improved without increasing its thickness.

Glass fibers have a chemical composition that includes the following constituents, in a weight content that varies within the limits defined below: SiO.sub.2 50-70%, Al.sub.2O.sub.3 0-5%, CaO+MgO 0-7%, Na.sub.2O 5-15%, K.sub.2O 0-10%, BaO 2-10%, SrO 2-10%, ZnO<2%, and B.sub.2O.sub.3 5-15%.

A nonwoven fibrous insulation product has at least a bi-modal fiber diameter distribution designed to provide the product with selected thermal insulating and physical performance properties that are affected by fiber diameter such as rigidity and recovery properties. The product is made by: forming two or more fiber groupings that each have a selected fiber diameter distribution with a selected mean fiber diameter wherein the selected fiber diameter distributions of the fiber groupings differ from each other. The fibers of the fiber groupings are intermingled and entangled together in selected percentages by weight to form a product with a selected density and thickness that exhibits selected product performance properties based on the properties of the fiber groupings and the relative percentages by weight of the fiber groupings.

The invention relates to a thermal insulation product based on mineral wool comprising mineral fibers, the product comprising two main faces and longitudinal and transverse edges perpendicular to the main faces, the product being characterized by the following orientation fractions: a longitudinal orientation fraction greater than or equal to 48%, or even 50%, along an angle of more or less 6? with respect to the plane of the main faces, when the mineral fibers are counted only in a longitudinal cross-section, and a mean orientation fraction greater than or equal to 40%, or even 45%, along an angle of more or less 6? with respect to the plane of the main faces, when the mineral fibers are counted both in a transverse cross-section and in a longitudinal cross-section. The invention allows the insulating power of a thermal insulation product based on mineral wool to be improved without increasing its thickness.

A mineral fiber forming device including: a centrifuge configured to rotate about a rotation axis, the centrifuge including an annular wall pierced by a plurality of orifices, the axis of symmetry of the annular wall being the rotation axis; a first annular inductor configured to heat a top part of the annular wall; a second annular inductor configured to heat a bottom part of the annular wall. The device makes it possible to increase its energy efficiency and very greatly reduce, even cancel altogether, its carbon dioxide emission level.

A thermal insulation product based on mineral wool, characterized in that the fibers have a micronaire of less than 10 l/min, preferably less than 7 l/min and especially between 3 and 6 l/min, and in that the material has a thermal conductivity of less than 31 mW/m.Math.K, especially less than 30 mW/m.Math.K. The parameters for obtaining this product are in particular the pressure of the burner, the rotation speed of the fiberizing spinner and the daily fiber output per spinner orifice.

A mineral fiber forming device including: a centrifuge configured to rotate about a rotation axis, the centrifuge including an annular wall pierced by a plurality of orifices, the axis of symmetry of the annular wall being the rotation axis; a first annular inductor configured to heat a top part of the annular wall; a second annular inductor configured to heat a bottom part of the annular wall. The device makes it possible to increase its energy efficiency and very greatly reduce, even cancel altogether, its carbon dioxide emission level.

A thermal insulation product based on mineral wool, characterized in that the fibers have a micronaire of less than 10 l/min, preferably less than 7 l/min and especially between 3 and 6 l/min, and in that the material has a thermal conductivity of less than 31 mW/m.Math.K, especially less than 30 mW/m.Math.K. The parameters for obtaining this product are in particular the pressure of the burner, the rotation speed of the fiberizing spinner and the daily fiber output per spinner orifice.