Performance Benefits

  • Long Life – Therminol 55 is a true 290°C (550°F) fluid. You will get years of reliable, cost effective performance, even when operating your system continuously at 290°C (550°F). This means you do not have to over specify your fluid.
  • Non Fouling – Excellent resistance to fouling - Because Therminol 55 is a synthetic fluid, it resists the effects of oxidation 10 times better than mineral oils. Less oxidation and solids formation. For systems without nitrogen inerting, the performance advantages are significant.
  • Superb Low Temperature Pumpability – Excellent Low Temperature Pumpability - Therminol 55 is still pumpable at -25°C (-15°F ), compared to some mineral oils that will not pump at temperatures below -7°C (20°F ). With Therminol 55, your heat transfer fluid system can start-up quickly and easily.

Typical Properties

AppearanceClear yellow liquid
CompositionSynthetic hydrocarbon mixture
Maximum bulk temperature290°C (550°F)
Extended maximum use temperature315°C (600°F)
Maximum film temperature335°C (635°F)
Normal boiling point351.0°C (664.0°F)
Pumpability, at 300 mm2/s (cSt)-8°C (17°F)
Pumpability, at 2000 mm2/s (cSt)-28°C (-19°F)
Freezing point-40°C (-40°F)
Flash point COC (ASTM D-92 / DIN 51376)177°C (350°F)
Autoignition temperature (ASTM E-659)343°C (650°F)
Autoignition temperature (ASTM D-2155)357°C (657°F)
Pour point (ISO 3016)-54.0°C (-65.0°F)
Minimum liquid temperatures for fully developed turbulent flow (NRe > 10000)
10 ft/sec, 1 in tube (3.048 m/s, 2.54 cm tube)67°C (152°F)
20 ft/sec, 1 in tube (6.096 m/s, 2.54 cm tube)45°C (114°F)
Minimum liquid temperatures for transitional region flow, (NRe > 2000)
10 ft/sec, 1 in tube (3.048 m/s, 2.54 cm tube)24°C (75°F)
20 ft/sec, 1 in tube (6.096 m/s, 2.54 cm tube)11°C (52°F)
Heat of vaporization at max. use temperature228.0 kJ/kg (98.1 Btu/lb)
Kinematic viscosity at 100°C (ASTM D-445 / DIN 51562)3.52 mm2/s (cSt)
Kinematic viscosity at 40°C (ASTM D-445 / DIN 51562)19.00 mm2/s (cSt)
Liquid density at 25°C (ASTM D-4052 / DIN 51757)868.0 kg/m3 (7.30 lb/gal)
Average molecular weight320
Pseudocritical temperature512.0°C (953.0°F)
Pseudocritical pressure13.2 bar (191.0 psia)
Pseudocritical density258.00 kg/m3 (16.10 lb/ft3)
Moisture content, maximum (ASTM E-203 / DIN51777)250 ppm
Dielectric constant @ 23°C (ASTM D-924)2.23
Notice: Although the information and recommendations set forth herein are presented in good faith, Eastman Chemical Company and its wholly owned subsidiary Solutia Inc. make no representations or warranties as to the completeness or accuracy thereof. You must make your own determination of their suitability and completeness for your own use, for the protection of the environment, and for the health and safety of your employees and purchasers of your products. Nothing contained herein is to be construed as a recommendation to use any product, process, equipment, or formulation in conflict with any patent, and we make no representations or warranties, express or implied, that the use thereof will not infringe any patent. NO REPRESENTATIONS OR WARRANTIES, EITHER EXPRESS OR IMPLIED, OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR OF ANY OTHER NATURE ARE MADE HEREUNDER WITH RESPECT TO INFORMATION OR THE PRODUCT TO WHICH INFORMATION REFERS AND NOTHING HEREIN WAIVES ANY OF THE SELLER'S CONDITIONS OF SALE.

Safety Data Sheets providing safety precautions that should be observed when handling and storing our products are available online or by request. You should obtain and review available material safety information before handling our products. If any materials mentioned are not our products, appropriate industrial hygiene and other safety precautions recommended by their manufacturers should be observed.