Verre — Viscosité et points viscosimétriques fixes — Partie 6: Détermination de la température de ramollissement

The temperatur above which the glass is capable of most forming operations is determined by measuring the elongation of a round glass fibre under its own weight. Closely defines requirements for the test specimen, procedure and apparatus lead to optimum repeatability of the specified temperature point. The furnace is specified with essential aspects.