Glass fiberization

Claim 2

A glass fiber insulation blanket produced by a process comprising: heating to molten attenuable condition a glass having the following composition: ______________________________________ SiO.sub.2 61 to 72% Al.sub.2 O.sub.3 2 to 8% Fe.sub.2 O.sub.3 0.2 to 1% CaO 4.7 to 7.5% MgO 0 to 5% Na.sub.2 O + K.sub.2 O 14 to 18% B.sub.2 O.sub.3 0 to 6% F 0 to 1.5% BaO 0 to 2.5% ZrO.sub.2 0 to 2.5% Misc ≦1% ______________________________________ introducing the molten glass into a spinner for delivery to the interior surface of the spinner peripheral wall, said spinner peripheral wall having a multiplicity of orifices therein; rotating said spinner to effect the centrifugal passage of the molten glass through the spinner orifices in a multiplicity of streams; attenuating said glass streams into fibers by means of an internal combustion burner providing a generally downwardly directed annular gaseous blast adjacent the exterior of said spinner peripheral wall, said gaseous blast having an elevated temperature contributing to the maintenance of the glass streams in attenuable condition for a time sufficient to effect attenuation thereof, the centrifugal acceleration at the spinner peripheral wall, the spinner diameter, the peripheral velocity of the spinner, and the burner pressure falling within the following ranges: ______________________________________ centrifugal acceleration 4000 m/sec.sup.2 to 20000 m/sec.sup.2 spinner diameter 550 mm to 1500 mm peripheral velocity 50 m/s to 130 m/s burner pressure 100 mm to 900 mm (water column) ______________________________________ and collecting said fibers in the form of a blanket on a foraminous substantially horizontal conveyor disposed beneath said spinner, the glass fiber of said blanket having the following characteristics: ______________________________________ fineness 2 (5 g) to 5 (5 g) micronaire conductivity 30 × 10.sup.-3 to 55 × 10.sup.-3 (W/m° K.) density 8 to 75 (Kg/m.sup.3). ______________________________________

Claim 3

A glass fiber insulation blanket produced by a process comprising: heating to molten attenuable condition a glass having the following composition: ______________________________________ SiO.sub.2 61 to 72% Al.sub.2 O.sub.3 2 to 8% Fe.sub.2 O.sub.3 0.2 to 1% CaO 4.7 to 7.5% MgO 0 to 5% Na.sub.2 O + K.sub.2 O 14 to 18% B.sub.2 O.sub.3 0 to 6% F 0 to 1.5% BaO 0 to 2.5% ZrO.sub.2 0 to 2.5% Misc ≦1% ______________________________________ introducing the molten glass into a spinner for delivery to the interior surface of the spinner peripheral wall, said spinner peripheral wall having a multiplicity of orifices therein; rotating said spinner to effect the centrifugal passage of the molten glass through the spinner orifices in a multiplicity of streams; attenuating said glass streams into fibers by means of an internal combustion burner providing a generally downwardly directed annular gaseous blast adjacent the exterior of said spinner peripheral wall, said gaseous blast having an elevated temperature contributing to the maintenance of the glass streams in attenuable condition for a time sufficient to effect attenuation thereof, the centrifugal acceleration at the spinner peripheral wall, the spinner diameter, the peripheral velocity of the spinner, and the burner pressure falling within the following ranges: ______________________________________ centrifugal acceleration 4000 m/sec.sup.2 to 20000 m/sec.sup.2 spinner diameter 550 mm to 1500 mm peripheral velocity 50 m/s to 130 m/s burner pressure 100 mm to 900 mm (water column) ______________________________________ and collecting said fibers in the form of a blanket on a foraminous substantially horizontal conveyor disposed beneath said spinner, the glass fiber of said blanket having the following characteristics: ______________________________________ fineness 2 (5 g) to 5 (5 g) micronaire conductivity K at 24° C. 30 × 10.sup.-3 to 55 × 10.sup.-3 (W/m°K) density 8 to 75 (Kg/m.sup.3) ______________________________________ wherein conductivity (K) and density (ρ) are interrelated according to the following formula: K=A+B(ρ)=C/ρ in which A=25.89×10 -3 B=0.02×10 -3 to 0.2×10 -3 C=0.100 to 0.300.

Claim 4

A glass fiber insulation blanket produced by a process comprising: heating to molten attenuable condition a glass having the following composition: ______________________________________ SiO.sub.2 61 to 72% Al.sub.2 O.sub.3 2 to 8% Fe.sub.2 O.sub.3 0.2 to 1% CaO 4.7 to 7.5% MgO 0 to 5% Na.sub.2 O + K.sub.2 O 14 to 18% B.sub.2 O.sub.3 0 to 6% F 0 to 1.5% BaO 0 to 2.5% ZrO.sub.2 0 to 2.5% Misc ≦1% ______________________________________ introducing the molten glass into a spinner for delivery to the interior surface of the spinner peripheral wall, said spinner peripheral wall having a multiplicity of orifices therein; rotating said spinner to effect the centrifugal passage of the molten glass through the spinner orifices in a multiplicity of streams; attenuating said glass streams into fibers by means of an internal combustion burner providing a generally downwardly directed annular gaseous blast adjacent the exterior of said spinner peripheral wall, said gaseous blast having an elevated temperature contributing to the maintenance of the glass streams in attenuable condition for a time sufficient to effect attenuation thereof, the centrifugal acceleration at the spinner peripheral wall, the spinner diameter, the peripheral velocity of the spinner, and the burner pressure falling within the following ranges: ______________________________________ centrifugal acceleration 4000 m/sec.sup.2 to 20000 m/sec.sup.2 spinner diameter 550 mm to 1500 mm peripheral velocity 50 m/s to 130 m/s burner pressure 100 mm to 900 mm (water column) ______________________________________ and collecting said fibers in the form of a blanket on a foraminous substantially horizontal conveyor disposed beneath said spinner, the glass fiber of said blanket having the following characteristics: ______________________________________ fineness 2 (5 g) to 5 (5 g) micronaire conductivity K at 24° C. 30 × 10.sup.-3 to 55 × 10.sup.-3 (W/m°K) density 8 to 75 (Kg/m.sup.3) ______________________________________ wherein conductivity (K) and density (ρ) are interrelated according to the following formula: K=A+B(ρ)=C/ρ in which A=25.89×10 -3 B=0.02×10 -3 to 0.2×10 -3 C=0.100 to 0.300.

Claim 5

Mat formed of fibers of a glass material, the fibers being produced by passing material in a molten state through orifices placed on the periphery of a spinner and being attenuated by gas currents surrounding the spinner, characterized in that the mass of particles of which the diameter is greater than 10 times the average diameter of the fibers constitutes less than 1% of the mass of the mat.

Claim 6

Mat formed of fibers of a glass material, the fibers being produced by passing material in a molten state through orifices placed on the periphery of a spinner and being attenuated by gas currents surrounding the spinner, characterized in that the mass of particles of which the diameter is greater than 10 times the average diameter of the fibers constitutes less than 1% of the mass of the mat.

Claim 7

Mat according to claim 3 wherein the mass of particles of which the diameter is greater than 20 times the average diameter of the fibers constitutes less than 0.30% of the mass of the mat.

Claim 8

Mat formed of fibers of a glass material, the fibers being produced by passing the material in a molten state through orifices placed on the periphery of a spinner and being attenuated by gas currents surrounding the spinner, characterized in that the mass of unfiberized particles of which the apparent diameter is greater than 40 micrometers represents no more than 1% of the mass of fibers forming the mat.

Claim 9

Mat formed of fibers of a glass material, the fibers being produced by passing the material in a molten state through orifices placed on the periphery of a spinner and being attenuated by gas currents surrounding the spinner, characterized in that the mass of unfiberized particles of which the apparent diameter is greater than 40 micrometers represents no more than 1% of the mass of fibers forming the mat.

Claim 10

Mat according to claim 5 in which the mass of unfiberized particles, of which the diameter is greater than 40 micrometers, represents no more than 0.80% of the entire mass of fibers forming the mat.

Claim 11

Mat according to claim 5 in which the ponderal proportion of the unfiberized particles of which the diameter is greater than 80 micrometers is no more than 0.30%.

Claim 12

Mat formed of fibers of a glass material, the fibers being produced by passing the material in a molten state through the orifices placed on the periphery of a spinner and being attenuated by gas currents surrounding the spinner, characterized in that the coefficient of variation of the diameter of the fibers is less than 0.65%.

Claim 13

Mat formed of fibers of a glass material, the fibers being produced by passing the material in a molten state through the orifices placed on the periphery of a spinner and being attenuated by gas currents surrounding the spinner, characterized in that the coefficient of variation of the diameter of the fibers is less than 0.65%.

Claim 14

Mat according to claim 8, characterized in that the coefficient of variation of the diameter of the fibers is less than 0.6.

Claim 15

Mat formed of a glass material, the fibers being produced by passing the material in a molten state through orifices placed on the periphery of a spinner and being attenuated by gas currents surrounding the spinner, characterized in that the ratio of the specific weight, or mass per surface unit, m expressed in kg/m 2 to the thermal resistance at 297° K. expressed by m 2 .°K./W, is at most equal to 0.026 p+0.2, p being the volumetric mass of the mat in kg/m 3 .

Claim 16

Mat formed of a glass material, the fibers being produced by passing the material in a molten state through orifices placed on the periphery of a spinner and being attenuated by gas currents surrounding the spinner, characterized in that the ratio of the specific weight, or mass per surface unit, m expressed in kg/m 2 to the thermal resistance at 297° K. expressed by m 2 .°K./W, is at most equal to 0.026 p+0.2, p being the volumetric mass of the mat in kg/m 3 .

Claim 17

Mat according to any one of claims 3, 5, 8 or 10, characterized in that the amount of dust freed by a specimen subjected to the final test in the application is less than 0.1 mg/m 2 of border surface.

Claim 18

Mat according to any one of claims 3, 5, 8 or 10, characterized in that the tensile strength to the rings (ASTM-C 681-76) in the direction of the length of the mat is at least equal to 200 gf/g.

Claim 19

Mat according to any one of claims 3, 5, 8 or 10, characterized in that its resistance to the passage of air (ISO-DIS-4638) is at least 4 Rayl/cm for a volumetric mass of 10 kg/m 3 .

Claim 20

Mat according to any one of claims 3, 5, 8 or 10, characterized in that its resistance to the passage of air is at least 10 Rayl/cm for a volumetric mass of 20 kg/m 3 .

Claim 21

Mat according to any one of claims 3, 5, 8 or 10, wherein the compression rate for a storage time of three months is greater than or equal to 5.