The three current TEOST® tests operate under temperatures and environmental conditions identified as significant in internal combustion engines to simulate the oxidation and deposit-forming tendencies of engine oils. Oil samples, treated with catalyst, are pumped over a heated steel Depositor Rod on which deposits form. The weight of the Depositor Rod after the test is subtracted from its pre-test weight and added to the particulate weight collected by filtering the remaining oil. The results are reported in milligrams.
In the mid-1980s, Savant Labs developed a unique two-stage oxidation/deposition test technique for engine oils formulated for high-temperature performance. Joint cooperation with Chrysler Corporation resulted in a modified, very high temperature cyclic technique successfully applied to oils blended for turbocharger lubrication temperatures. The technique, known as TEOST® 33C, became ASTM D6335, and Savant Labs received a Chrysler Technology Award in 1993.
Additional work proved successful in modifying the TEOST® to measure deposits on a thin-film of circulating oil. This lower, but constant temperature application, correlated to the piston ring belt area of the combustion engine. The TEOST MHT® (Moderately High Temperature) protocol later became ASTM D7097. International engine oil specifications now include both 33C and MHT®.
As engine designs have evolved over the years, particularly turbochargers, the need for an additional modification to the TEOST® platform became evident with the trends in increasing oil change intervals, improved fuel efficiency, and longer residence times for turbocharger cooling. Development began in 2017 on a new lower-temperature, high-duty cycle deposit test to accurately assess deposit formation in modern engines. This technique, known as TEOST Turbo®, became ASTM D8447 in 2022.
33C Reference Oils | ASTM D6335 | MHT® Oils & Catalyst | ASTM D7097 | TEOST® Calibration Oil | Turbo® | ASTM D8447 |
---|---|---|---|
CG-1 | LDF-4 | TPC-1 | MDF-4 |
T33C-1 | MDF-4 | ||
HDF-4 |
For a complete listing of part numbers and available container sizes of Tannas Reference Oils, please review the Tannas Reference Oils & Catalysts Parts List.
Visit our Certified Reference Materials page to download SDS sheets or Oil Certificates.
Instruments:
500700: TEOST® Trident, 110V, 50/60 Hz Power
500800: TEOST® Trident, 220V, 50/60 Hz Power
Depositor Rods:
500020: TEOST® 33C Depositor Rods (10 rods/box)
500021: TEOST MHTurbo® Depositor Rods (10 rods/box)
Optional Accessories:
500990: Trident Mass Flow Controller
500995: MHT® Mass Flow Controller
500075: Thermocouple Depth Gauge
500070: Two-Channel Chart Recorder – R
500065: Chart Recorder Paper – R
500024: Chart Recorder Pen – Black
500067: Chart Recorder Pen – Red
Spare Parts & Consumables
501000: TEOST Turbo® Parts Assembly
500030: TEOST® Filter Cartridges w/Caps
500612: T/C Main (J-type)
500614: T/C Over-Temp. (K-type)
500409: Depositor Rod O-Rings (20/pack)
500892: Filtering Flask Funnel
500016: Steel Wool
500019: Pipe Cleaners (100/box)
500084: Disposable Pipette
500872: Thermocouple Collar Assembly
200103: Syringe (100 microliters)
500076: Weighing Boats
Allen Keys for cabinet (P/Ns 500610, 500611, 500613)
Contact Tannas for additional spare parts, reference oils, and accessories to run the Turbo®, MHT® and 33C tests.
Depositor Rods crafted from precision machined steel meet Tannas specifications for exclusive use in TEOST® tests. All rods undergo a rigorous inspection and measurement process prior to acceptance.
Mass Flow Controllers, utilized for all three TEOST® tests, introduce various components to the test oil such as reactive gases and air. The MHT® Mass Flow Controller solely operates with the D7097 test, while the Trident Mass Flow Controller operates with both ASTM D6335, D7097, and D8447 tests.