Fluids and Elastomers for Low-Temperature Heat Transfer and Hydraulic Systems

• Published in: ASLE transactions 1966-01, Vol.9 (1), p.59-66
• Main Author: Armstrong, C. S.
• Format: Article
• Language: English
• ISSN: 0569-8197
• DOI: 10.1080/05698196608972122

Five fluids (a dimethyl silicone, a silicate ester, a branched chain chloro-fluorocarbon, a cyclic fluorinated ether and a fluorinated polyether) were evaluated for use as the fluid in a single pass, gas actuated hydraulic system capable of operation from −150 to 275 F. Important physical and chemical properties, including thermal stability, lubricity, viscosity, pour, low-temperature characteristics and flash point, were determined. Specific heat, thermal conductivity and density values were compiled from manufacturer's data. The fluorinated polyether was chosen as the most suitable fluid for the low-temperature system. The phenyl silicones were determined to be the only elastomers suitable for use in dynamic and static seals of the system. Several typical phenyl silicone compounds were tested for compatibility with the five low-temperature fluids. Leakage tests were run in a static seal fixture with several of the fluids. A proprietory phenyl silicone compound was chosen as the best material for use with the fluorinated polyether. Fluid and elastomer performance in the low-temperature system are covered briefly. Presented as an American Society of Lubrication Engineers paper at the Lubrication Conference held in San Francisco, Calif., October 18-20, 1965.