Temperature stability is critical for ASTM D445 Kinematic Viscosity

Temperature control is the single most important parameter for obtaining accurate and precise kinematic viscosity measurements. For petroleum products even more so, as their rate of viscosity change per unit of temperature is significantly greater than other types of materials. Thus, a slight variation in temperature can have a very large effect on the viscosity of a fluid. the bath temperature for most high temperature measurements, 40 degrees C and 100 degrees C, must be controlled to within +/- 0.002 deg. C and for low temperatures, typically -20 deg. C and -40 deg. C, a stability of +/- 0.05 deg C is required. That is an extremely tight window and great care must be taken to achieve this control.

Lawler Model 86-20 High Temperature Viscosity Bath is designed with tight 0.02 degree temperature stability in mind. Instead of an open bath jar, an enclosed cabinet design is used to prevent room drafts from affecting temperature. And more importantly, a sophisticated process grade temperature controller is used with 0.01 degree resolution. It is the only one on the market used with such resolution. Other units use 0.1 degree resolution controllers which make it impossible to verify the 0.02 or even 0.05 degree stability requirement. http://www.lawlercorp.com/d445_high.html

Lawler Model 70 Series Low Temperature Kinematic Viscosity Baths are similar and additionally are built with Lawler's advanced refrigeration system to reach temperatures as low as -70 degrees C with +/-0.05 temperature stability or better. http://www.lawlercorp.com/D445_1_UK.htm

ASTM D2983 Low Temp. Brookfield Viscosity Spindle Clips

At the suggestion of a customer many years ago, there is a very simple and inexpensive method to making the spindle suspension clips using an ordinary paper clip. Cut the paper clip per this drawing.

Water Separability Paddle Cleanliness

With all the concern for cleanliness of the glassware for this ASTM D1401 test, it was recently discovered that the paddle itself may cause cleanliness problems. Most paddles are soldered to the shaft. It is unclear how to thoroughly clean soldered edges. To eliminate any possibility of impurities, the paddle and shaft should be one piece of metal. Lawler supplies a one piece paddleand shaft to address this concern. Learn more about out D1401 Water Separability bath here: http://www.LawlerCorp.com/d1401.html