METHOD FOR TEMPERING GLASS SHEETS

摘要

A method for tempering substantially flat glass sheets. A glass sheet is heated to a tempering temperature and quenching is conducted by blasting cooling air to both surfaces of the glass sheet. The quenching of a top surface and a bottom surface of the glass sheet's both side lanes is commenced earlier or is performed at the early stage of quenching more effectively than the quenching of a top surface and a bottom surface of the glass sheet's middle lane. As a result, the compressive stress required for a desired tempering degree is established on both surfaces of the side lanes earlier than on both surfaces of the middle lane. In order to achieve this, the cooling air enclosures above and below a glass sheet are provided with a subarea of weakened cooling effect.

主权项

1. A method for tempering glass sheets, which comprises heating a glass sheet to a tempering temperature and conducting a quenching step by blasting cooling air to both surfaces of the glass sheet, wherein, in order to eliminate the bi-stability of a tempered, substantially flat glass sheet, the quenching of a top surface and a bottom surface of the glass sheet's both side lanes is commenced earlier or performed at the early stage of quenching more effectively than the quenching of a top surface and a bottom surface of the glass sheet's middle lane, and thereby the compressive stress required for a desired tempering degree is established on both surfaces of the side lanes earlier than on both surfaces of the middle lane.