THE USE OF PGM STIRRERS IN SUBSTRATE GLASS TO INFLUENCE GLASS HOMOGENEITY

Since 1985, Eglasstrek has gone down new paths and used PGM (Platinum Group Metals) paddle stirrers for technical and LCD substrate glass.

The special stirrer construction which has now been technically optimized guarantees that all molten glass particles are subjected to the maximum shear force. In the stirrer chamber, the molten glass is exposed to a local high velocity differential. The increasing shear force acting on the glass results in a completely thermal and above all chemical homogeneity of the molten glass passing through of suitable viscosity.

Eglasstrek stirrers avoid platinum inclusions, so as to ensure low viscosity and rotation (0.5 - 6 RpM). Further, the cross-section of the annular connector between the stirrer body (75 - > 120 mm in diameter) and the platinum stirrer chamber (200 - > 250 mm in diameter) is kept small, whereby the paddles welded on to the stirrer body can be about 20 -75 mm. It is helpful to keep the paddle at the end of the stirrer at an angle to increase the stirrer function.

Moreover, our stirrers placed on the floor have an arched paddle. These parts move the glass in the area below the stirrers and therefore allow no stationary parts. The molten glass leaving the stirrer chamber has a viscosity of < 10³ dPa dependent on technical specifications.

Experience has shown that with our system cord free substrate glass for LCD FLOAT® and also Overflow Fusion can be produced. With the help of Eglasstrek know-how established glass producers world wide use the stirrer system for LCD floaT® and produce 30 to 40 tons per day. The concept can be altered to accommodate higher tonnage.