Glass Viscometers

PSL Rheotek glass viscometers are mouth blown from low-expansion borosilicate glass tubing in our glassblowing workshop in Essex. The precision bore used for the capillary section is held to the close tolerance of ± 0.01mm. Glass viscometers are clearly marked with timing lines and other inscriptions as well as a unique serial number. A glass bridge is provided to give additional strength and the finished instrument is fully annealed.

For measuring transparent liquids, we recommend the ASTM Ubbelohde viscometer. The constant of this viscometer is temperature independent. Designed with an air arm, which has access to atmoshpere, the ASTM Ubbelohde Viscometers returns accurate results using an approximate quantity of sample.  For measuring opaque liquids, we recommend the U-Tube reverse flow viscometer.