Glass Wool Producing Process
Jeffrey G. Gardner, David H. Keating, in Methods in Enzymology, 2012
6.2 Cell capture during growth in insoluble carbon sources
6.2.1 Removal of cells by filtration
Glass wool was placed at the bottom of a 50-ml syringe. The suspension of cells/phenol:ethanol stop solution was then forced through the syringe, trapping the insoluble carbon source in the glass wool, and the cells collected in a tube. The cells were then recovered by centrifugation as described above. A limitation of this method was the low flow rate resulting from the presence of the insoluble material.
An alternative method for separation of cells from insoluble material involves the use of a very low speed spin at 500 × g for 5 min at 4 °C to pellet the insoluble carbon sources, but not the cells. The cell suspension was then transferred to a fresh 50 ml conical tube and subjected to a subsequent high-speed spin at 10,000 × g for 5 min at 4 °C to recover the cells. The cells were then flash frozen and subjected to RNA extraction as discussed in the following sections.
John Willoughby, in Plant Engineer's Reference Book (Second Edition), 2002
30.9.2 Glass wool
Glass wool is made from borosilicate glass whose principal constituents are sand, soda ash dolomite, limestone, ulexite and anhydrite. They are melted in a furnace at about 1400°C and then fed along a channel to a forehearth, where the glass flows through bushings into spinners. These rapidly rotating spinners have several thousand small holes around the perimeter through which the glass is forced by centrifugal force to become fibreized. Immediately after formation, the fibres are sprayed with resinous binders, water repellents and mineral oils as appropriate and fall under suction onto a moving conveyor which takes the wool to one of three production lines (Figure 30.3).
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Figure 30.3. The glass wool manufacturing process. 1 Tank; 2 forehearth; 3 spinners; 4 conveyor; 5 curing oven; 6 trimmers; 7 slitters; 8 bandsaw; 9 guillotine; 10 rolling machine
220.127.116.11 Main line
The wool passes through an oven which cures the resinous binder and determines the thickness of the product. On leaving the oven, the insulation is trimmed, slit and chopped into the appropriate product length prior to reaching the packing station, where it is either packaged as rolls or slabs.
The uncured wool from the forming conveyor is separated into ‘pelts’ which are converted into pipe sections by being wrapped around a heated mandrel and the wall thickness set by counter rollers. The sections are then passed through a curing oven before being trimmed, slit, covered and packaged.
18.104.22.168 Blowing wool line
The water-repellent wool is shredded by a flail and pneumatically transferred to a rotating drum nodulator to be further processed before bagging.
22.214.171.124 Product range
A wide product range, from lightweight mats through flexible and semi-rigid, to rigid slab. Pipe sections, loose wool, blowing wool, moulded products and mattresses.
126.96.36.199 Typical properties
Glass wool products have a limiting temperature of 540°C but are mostly used in buildings and H & V applications where a limiting working temperature of 230°C is recommended.
Fire safety Basic wool is non-combustible to BS 476:
Density range 10–75 kg/m3.
Thermal conductivity 0.04–0.03 W/mK at 10°C mean: 0.07–0.044 W/mK at 100°C mean.
Ozone depletion ZODP
188.8.131.52 Special applications
Acoustic absorption in duct lining and splitters. Decorative facings for ceiling and lining panels. Tensile strength for good draping qualities. Loft insulation up to 200 mm thick, cavity wall insulation. Fire stopping and small-cavity fire barriers.
The Whole Glass Wool Producing Process is finished.