8 General Operation
8.1.10.3Mineral Oil
Mineral oil or paraffin oil is often used at moderate temperatures above the range of water. Mineral oil is relatively inexpensive. At lower temperatures mineral oil is quite viscous and control may be poor. At higher temperatures vapor emission becomes significant. The vapors may be dangerous and use of a fume hood is highly recommended. As with most oils mineral oil will expand as temperature increases so be careful not to fill the bath too full that it over- flows when heated. The viscosity and thermal characteristics of mineral oil is poorer than water so temperature stability will not be as good. Mineral oil has very low electrical conductivity. Use caution with mineral oil since it is flam- mable and may also cause serious injury if inhaled or ingested.
8.1.10.4Silicone Oil (Dow Corning 200.05, 200.10, 200.20)
Silicone oils are available which offer a much wider operating temperature range than mineral oil. Like most oils, silicone oils have temperature control characteristics which are somewhat poorer than water. The viscosity changes significantly with temperature and thermal expansion also occurs. These oils have very high electrical resistivity. Silicone oils are fairly safe and
8.1.10.5Halocarbon 0.8
Halocarbon 0.8 is a low temperature fluid with a wide temperature range. It may be used as low as
8.1.11Fluid Characteristics Table
Table 2 on page 31 provides help in selecting a heat exchange fluid media for your constant temperature bath. This table provides a numerical representation of most of the physical qualities important in making a selection. The list is not all inclusive. There may be other useful fluids not shown in this listing.
The table includes information on a variety of fluids which are often used as heat transfer fluid in baths. Because of the temperature range some fluids may not be useful with your bath.
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