| 摘要 |
In a method of making a glass sheet using an overflow fusion downdraw process, a glass sheet quality metric level Q1 is selected, where Q1 is a measure of allowable retardation in the glass sheet. A glass ribbon temperature T1 at which a potential glass ribbon thermal artifact could occur in a glass ribbon while the glass ribbon is being drawn through a drawing machine enclosure is identified. A thermal artifact envelope E1 is determined, where E1 contains types of glass ribbon thermal artifacts allowable at T1 and Q1. A glass melt is overflowed from an isopipe to form a glass ribbon at the root of the isopipe. The glass ribbon is drawn below the root of the isopipe through the drawing machine enclosure to form the glass sheet. The drawing machine enclosure is altered at a location corresponding to where the glass ribbon would be at T1 such that during drawing of the glass ribbon the potential glass ribbon thermal artifact is not formed in the glass ribbon at T1 or, if the potential glass ribbon thermal artifact is formed in the glass ribbon at T1, the potential glass ribbon thermal artifact is within E1. |
