Test cell innovation enables simple and reliable ASTM D2983 testing for low-temperature viscosity of ATF, hydraulic fluids, and lubricants

An acceleration of low-temperature studies by automobile manufacturers began in the 1950s due to the failure of automatic transmissions in cold temperatures.  Later, in 1971, a procedure was written and accepted as ASTM D2983.  The original technique used a balsa wood block to hold samples in a cold air cabinet. The samples were removed from the cabinet and tested with a rotational, bench-top Viscometer.  In the mid-1990s, Tannas developed and patented the SimAir® Test Cell for use in a ‘constant’ temperature liquid bath to dramatically improve the test operation, usability, and precision of the test and licensed the technology to King Refrigeration for use in their low-temperature baths.

The innovative design of the SimAir® Test Cell allows the constant temperature baths offered by Tannas and King to closely simulate the sample cooling profiles of the original cold air cabinet technique during the 16-hour soak period.  Additionally, with each test cell cooling independently of the others in the bath, this permits flexibility in starting and stopping sample tests without affecting other samples in the bath.  With bath sample capacities of up to (12) test cells, this provides greater adaptability with increased sample throughput and improved precision over air baths, ‘programmable’ liquid baths, and other thermoelectrically cooled techniques.

The one viscometer, mounted on top of the bath, easily attaches to the SimAir® Spindles via a Quick Connect for viscosity measurements at the end of the designated soak period, while the sample remains at temperature in the liquid bath.  Since meniscus levels can fluctuate depending on sample type and temperature, the large viewing window of the bath allows the operator to properly align the Spindle immersion mark to the meniscus of the sample, according to the test method requirements.  The King BLB is a widely used low-temperature test for a variety of industry specifications.