Carbonaceous materials for the production of aluminium — Pitch for electrodes — Part 1: Determination of softening point by the ring-and-ball method
铝生产用碳素材料.电极用沥青.第1部分:用环球法测定软化点
This document specifies the ring-and-ball method, a method of using the ring-and-ball apparatus for the determination of the softening point (softening temperature) of pitch used in the production of aluminium.
The method is applicable to pitches having softening points equal to or greater than 30 °C.