ASTM subcommittee on flow behaviour of petroleum products started development of the new method in 2002, when an interlaboratory study was conducted to determine a precision and bias statement
The American Society for Testing and Materials (ASTM) has released the new standard D7042: Standard Test method for dynamic viscosity and density of liquids by Stabinger Viscometer (and the calculation of kinematic viscosity).
This method is based on the Stabinger Viscometer SVM 3000 from Anton Paar.
ASTM subcommittee D02.07A on flow behaviour of petroleum products started development of the new method in June 2002, when an interlaboratory study was conducted to determine a precision and bias statement for the new standard.
Twelve laboratories in the USA, Germany, Great Britain, Belgium, and Austria independently tested ten base oil stocks using the SVM 3000.
The results were compared to the same samples measured on kinematic viscometers in accordance with the ASTM D445 standard test method.
Digital density meters according to ASTM D4052 were used for density reference.
The precision obtained by the SVM 3000 in this study was shown to be equivalent to the D445 precision with no significant bias found between the methods.
The D7042 standard can be obtained online from ASTM.
The Stabinger Viscometer was introduced to the market in 2002.
The idea was to have an instrument as compact and easy to use as the well-known DMA series of bench-top density meters.
By using a frictionless floating rotor and eddy current torque measurement, this rotational viscometer achieves accuracy equivalent to traditional glass capillary viscometers while covering the whole range of Newtonian viscometry with one measuring geometry, says Anton Paar.
An integrated density cell displays both the dynamic and the kinematic viscosity.
The new method, which can be used in the place of D445, offers several significant advantages: faster measurements, no water bath required, very small space requirement, small sample (from 3ml) and solvent volume (from 6ml), automatic viscosity index measurement, optional low temperature measurements down to -56C.
One instrument covers the entire range - no capillaries to change
