Rotational Viscometers

 Note: Many of the following models have been replaced by the TBS2100E---Call or email for details!!!  

Tapered Bearing Simulator (TBS) Viscometer

Each of the TBS Viscometers described in this section are easy-to-operate, bench-top devices designed to measure high temperature high shear rates (HTHS) of lubricating oils and other fluids. The four different models of the TBS Viscometer (TBS500, TBS600, SuperShear TBS, and the TBS2100) are suitable for production control as well as excellent research tools. These TBS Viscometers are the only commercially available, very high shear (10⁵  to 7.5 • 10⁶  sec^-1  and beyond), broad temperature range, absolute viscometers. An Automation Package is also available for virtually unattended operation. 

The TBS Viscometer has been shown in ASTM studies to be the most accurate and precise of all high shear viscometers. It has also been shown in ASTM studies to closely correlate with, and predict, actual performance of engine oils in bearings. 

Samples can be analyzed on a continuous basis every five minutes. Using the chase-flush technique originally developed by Tannas, an oil sample is injected into the viscometer in a manner completely replacing the previous sample without the need for time-consuming solvent cleaning. With the use of a special Idling Oil, the unit can remain running indefinitely on standby. 

Depending on the temperature control source chosen, the operating temperature of the TBS line of instruments ranges from 40°C to over 200°C with close temperature control of +0.1°C.

Organic and water-based fluids, including engine oils, automatic transmission fluids, hydraulic fluids, inks, low-melting waxes and polymeric solutions have been tested on the TBS at viscosities ranging from 1 to 100 centipoise (cP). The TBS Viscometer meets the HTHS requirements in the SAE J300, ILSAC GF-2, and CEC L-36-A-90 specifications and is the instrument of choice for determining high shear absolute viscosity values used in the Viscosity Loss Trapezoid (VLT) now required for automatic transmission fluid and for railroad engine oil.