Glass manufacturing – Processes of manufacturing fibers – filaments – or preforms – Formation of fiber or preform utilizing fluid blast
Patent
1997-11-20
1999-05-04
Chin, Peter
Glass manufacturing
Processes of manufacturing fibers, filaments, or preforms
Formation of fiber or preform utilizing fluid blast
65460, 65466, 65510, 65521, 65522, 65524, C03B 3704, C03B 3706, C03B 544, C03B 3710
Patent
active
059000376
DESCRIPTION:
BRIEF SUMMARY
The invention relates to a method for producing mineral wool with the molten mineral material being fed into a spinner as defined in the opening clause of claim 1, and to an apparatus for fiberization of mineral material by means of internal centrifuging with a spinner as defined in the opening clause of claim 2.
Mineral fibers of high quality may be produced by internal centrifugation wherein the mineral melt is fed into the interior of a spinner rotating at high speed and having a multiplicity of small orifices in its peripheral wall wherethrough the melt may emanate as melt filaments of correspondingly small diameter. The exiting filaments are subjected to the blast of an annular burner and thereby attenuated to form fibers of a required fineness which subsequently solidify and accumulate on a lower conveyor where the mineral fiber mat is formed. Such process is well known in the art as so-called TEL process.
With such fiberizing units, mineral materials of varying compositions are fiberized. Such mineral compositions may have high, normal or low melting points and thus different fiberization temperatures. The burner of such fiberizing units, on the other hand, operates with a specified optimum adjustment and thus at a specified operation temperature which should not be changed substantially so as not to leave the region of optimum burner operation. Thus, the blast gases of the burner may have a temperature of 1550-1600.degree. C. with optimum burner operation adjustment, which would be a suitable temperature for fiberizing high-melting glasses. Through minor changes of the burner adjustment this temperature could be lowered to e.g. 1300-1350.degree. C. with still close to optimum burner adjustment so as to accommodate different temperature needs of lower melting glasses.
Overheating of the filaments of materials with low melting point will lead to a reduction of viscosity to such an extent that the melt attenuated by the blast gases will escape the attenuation zone before solidification such that, under the influence of surface tensions, the still molten fibers will transform into unfiberized particles undesirable in the resulting mineral wool mat.
Thus, there is a need to fiberize other mineral material like low-melting glasses with temperatures of the blast gasses as low as 1200.degree. C. or even less. Reduction of the burner outlet temperature to such extent by changing the burner adjustment would lead to non-optimum burner operating conditions which are undesirable.
It is thus an object of the present invention to provide a method and an apparatus which allow fiberization of low-melting mineral materials requiring substantially lower blast gas temperatures than produced by the burner at optimum operating conditions.
This object is attained in methodical respect in that the exit area of the burner is subdivided into an annular radially inner hot zone and an annular radially outer cooling zone of substantially lower temperature. In constructional respect, this object is obtained in that there are provided injection means for cooling gas like air in the outer peripheral wall of the burner outlet, and that the direction of injection is essentially transverse to the flow direction of the burner gases in the region of injection.
With the invention thus the temperature of the blast gases is not reduced homogenically as in the case where the admission of combustibles to the burner was reduced, or where cooling air was premixed to the burner gases. This has as consequence that the radially inner zone remains comparatively hot and possibly even at the temperature of the uncooled burner gases. This effect is desirable as the region of the rows of orifices in the peripheral wall of the spinner should be kept at comparatively high temperatures above the liquidus or the temperature of devitrification or cristallisation to allow the flow of glass through the orifices.
On the other hand, it is desirable to cool down the attenuated fibers rather rapidly so as to solidify them sufficiently to avoid a spring-back ef
REFERENCES:
patent: 2931062 (1960-04-01), Leaman
patent: 3304164 (1967-02-01), Charpentier et al.
patent: 5154746 (1992-10-01), Okuma et al.
patent: 5554324 (1996-09-01), Bernard et al.
patent: 5601628 (1997-02-01), Battigelli et al.
Aube Jean-Yves
Thouvenin Jean-Marie
Yang Alain
Chin Peter
Isover Saint-Gobain
Ruller Jacqueline A
LandOfFree
Method and apparatus for producing mineral wool does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for producing mineral wool, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for producing mineral wool will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1867519