ISO 7884-5:1987 Preview
Glass -- Viscosity and viscometric fixed points -- Part 5: Determination of working point by sinking bar viscometer
This standard was last reviewed and confirmed in 2010. Therefore this version remains current.
The specified method is suitable for characterizing the low-viscosity range of glass working: A vertically positioned narrow metal rod, i.e. the bar, is allowed to sink under its own weight into the melt. From the rate of sinking the dynamic viscosity is calculated. The teoretical basis relation and the apparatus including method of measurements are described.