tion with mineral oil since it is flammable and may also cause serious injury if
inhaled or ingested.
8.1.10.4
Silicone Oil
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 non-toxic.
Silicone oils are fairly expensive.
8.1.11
Fluid Characteristics Charts
CAUTION:
Due to the unique properties of silicone oils and their ability
to migrate and creep through seals, adequate ventilation must be used to
prevent oil vapors from creating an oily, dirty environment. Oily, dirty en-
vironments reduce the lifetime of the instruments electrical components.
Table 2 and Figure 4 on pages 32 and 33 have been created to provide help in
selecting a heat exchange fluid media for your constant temperature bath.
These charts provide both a visual and 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 charts include 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.
8.1.11.1
Limitations and Disclaimer
The information given in this manual regarding fluids is intended only to be
used as a general guide in choosing a fluid. Though every effort has been made
to provide correct information we cannot guarantee accuracy of data or assure
suitablility of a fluid for a particular application. Specifications may change
and sources sometimes offer differing information. Hart Scientific cannot be li-
able for any personal injury or damage to equipment, product or facilities re-
sulting from the use of these fluids. The user of the bath is responsible for
collecting correct information, exercising proper judgement, and insuring safe
operation. Operating near the limits of certain properties such as the flash point
or viscosity can compromise safety or performance. Your company’s safety
policies regarding flash points, toxicity, and such issues must be considered.
You are responsible for reading the MSDS (material safety data sheets) and act-
ing accordingly.
8.1.11.2
About the Chart
The fluid chart visually illustrates some of the important qualities of the fluids
shown.
31
8 General Operation
Heat Transfer Fluid
