Glass manufacturing – Processes – Forming product or preform from molten glass
Patent
1993-02-03
1994-06-28
Lindsay, Robert L.
Glass manufacturing
Processes
Forming product or preform from molten glass
65 8, 156 624, 222 55, C03B 3704
Patent
active
053243382
DESCRIPTION:
BRIEF SUMMARY
The invention concerns, in mineral felt production, a method for regulating a weight related parameter in the mineral fibre felt, by continuously adjusting the speed of the formed felt to the fibre flow from a fiberizing unit. The speed of the conveyors for the fibre felt are regulated by a first, feed-forward connected regulating device, wherein the measured value consists of the power consumption of the drive means for the fiberizing unit. This first regulating device is corrected by a second, feed-back connected regulating device, wherein the measured value consists of a weight related parameter of the fibre felt and this second regulating device is corrected in turn by a third feed-back connected regulating device wherein the measured value also consists of a weight related parameter of the fibre felt.
Mineral wool products are manufactured e.g. so that the necessary raw material is melted in a melting furnace, mineral melt is continuously withdrawn from the furnace through a discharge opening and converted to fibres in a fiberizing unit, which can e.g. consist of a plurality of rotating wheels, from which the mineral melt is slung under the formation of fibres. The thus formed fibres are transported by means of an air current from the fiberizing unit and are collected onto a conveyor in the form of a fibre felt. This felt can be of the desired final thickness, or form a so called primary web consisting of a thin layer of fibres, which thereafter are laid one on top of the other to form a secondary felt of the desired thickness, e.g. folded by means of a pendulum conveyor.
At some stage of manufacture, a suitable binder is added to the fibres, e.g. a resin, which at a final stage of the processing of the fibre felt is activated e.g. by heat. Thereby the fibres are fixed to each other under the formation of a form stable felt of the desired density and thickness, which thereafter is shaped to form the desired product.
The manufactured fibre felt should naturally exhibit as few as possible variations as to its structure, especially to its weight such as the weight of manufactured felt per time or length unit, its density and/or surface weight. This is achieved by maintaining the melt mass flow from the dicharge opening of the furnace as constant as possible and by regulating the speed of the fibre processing line following the fiberizing unit.
The speed of the fibre processing line is regulated on the basis of variations in the melt flow, which result in variations in the power consumption of the fiberizing unit, and on the basis of a weight related parameter of the fibre felt.
The invention is characterized in that a weight related parameter of the fibre felt, for example the surface weight of the fibre felt, is measured at least at two locations of the fibre felt. One of the locations is situated in the beginning of the felt forming line or procedure, where the felt has not necessarily yet been stabilized, and the second location is situated at the end of the felt forming line where the felt certainly has been stabilized, suitably somewhat before curing. The value which is measured in the beginning of the felt line is, over a second regulating device, used to carry out a correction on the first regulating device that regulates the speed of the conveyors. Obtaining a measurement result at an early stage, preferably as close as possible after the pendulum conveyor, makes it possible to carry out a rapid or immediate corrective regulation of the process system. Due to the fact that the felt has not stabilized itself completely at this point, this immediate measurement signal is not completely reliable. Although it reflects fairly well relative changes in the felt, the absolute level is not quite reliable and thus a second measurement signal is needed to correct the first one. According to the invention this second point of measurement is located at a distance from the first point of measurement, where the felt has been stabilized. This measured value from the later part of the fibre felt is in turn feed-b
REFERENCES:
patent: 4210432 (1980-07-01), Brelen et al.
patent: 4240815 (1980-12-01), Brelen et al.
patent: 4582520 (1986-04-01), Sturm
patent: 4592769 (1986-06-01), Lemaignen
Lindsay Robert L.
Paroc Oy AB
LandOfFree
Method for regulating a weight related parameter of a mineral fi 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 for regulating a weight related parameter of a mineral fi, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for regulating a weight related parameter of a mineral fi will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2375297