Fluke 7312, Руководство пользователя

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characteristics, which are somewhat poorer than water. The viscosity changes
significantly with temperature and also causes thermal expansion to occur.
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
Table 2 and Figure 6 on pages 36 and 37 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 to be used as
a general guide in choosing a fluid. Though every effort has been made to pro-
vide correct information we cannot guarantee accuracy of data or assure suit-
ability of a fluid for a particular application. Specifications may change and
sources sometimes offer differing information. Hart Scientific cannot be liable
for any personal injury or damage to equipment, product or facilities resulting
from the use of these fluids. The user of the bath is responsible for collecting
correct information, exercising proper judgment, and insuring safe operation.
Operating near the limits of certain properties such as the flash point or viscos-
ity can compromise safety or performance. Your company’s safety policies re-
garding flash points, toxicity, and such issues must be considered. You are
responsible for reading the MSDS (material safety data sheets) and acting
accordingly.
8.1.11.2 About the Graph
The fluid graph visually illustrates some of the important qualities of the fluids
shown.
Temperature Range: The temperature scale is shown in degrees Celsius. The
shaded bands indicate the fluids’ general range of application. Qualities includ-
ing pour point, freeze point, important viscosity points, flash point, boiling
point and others may be shown.
Freezing Point: The freezing point of a fluid is an obvious limitation to stir-
ring. As the freezing point is approached high viscosity may also limit
performance.
Fume Point: The point at which a fume hood should be used. This point is
very subjective in nature and is impacted by individual tolerance to different
fumes and smells, how well the bath is covered, the surface area of the fluid in
the bath, the size and ventilation of the facility where the bath is located and
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8 General Operation
Heat Transfer Fluid