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.
Pour Point:
This represents a handling limit for the fluid.
Viscosity:
Points shown are at 50 and 10 centistokes viscosity. When viscosity
is greater than 50 centistokes stirring is very poor and the fluid is unsatisfactory
for bath applications. Optimum stirring generally occurs at 10 centistokes and
below.
33
8 General Operation
Bath Fluid
Fluid
(# = Hart Part
No.)
Lower
Temperature
Limit*
Upper
Temperature
Limit*
Flash
Point
Viscosity
(centistokes)
Specific
Gravity
Specific Heat
(cal/g/°C)
Thermal
Conductivity
(cal/s/cm/°C)
Thermal
Expansion
(cm/cm/°C)
Resistivity
(10
12
-cm )
Halocarbon 0.8
#5019
–90°C (v)**
70°C (e)
NONE
5.7 @ –50°C
0.8 @ 40°C
0.5 @ 70°C
1.71 @ 40°C
0.2
0.0004
0.0011
Methanol
–96°C (fr)
60°C (b)
54°C
1.3 @ –35°C
0.66 @ 0°C
0.45 @ 20°C
0.810 @ 0°C
0.792 @ 20°C
0.6
0.0005 @ 20°C
0.0014 @ 25°C
Water
0°C (fr)
95°C (b)
NONE
1 @ 25°C
0.4 @ 75°C
1.00
1.00
0.0014
0.0002 @ 25°C
Ethylene
Glycol—50%
#5020
–35°C (fr)
90°C (b)
NONE
7 @ 0°C
2 @ 50°C
0.7 @ 100°C
1.05
0.8 @ 0°C
0.001
Mineral Oil
#5011
40°C (v)
190°C (fl)
190°C
15 @ 75°C
5 @ 125°C
0.87 @ 25°C
0.84 @ 75°C
0.81 @ 125°C
0.48 @ 25°C
0.53 @ 75°C
0.57 @ 125°C
0.00025 @ 25°C
0.0007 @ 50°C
5 @ 25°C
Dow Corning
200.5
Silicone Oil
–40°C (v)**
133°C (fl, cc)
133°C
5 @ 25°C
0.92 @ 25°C
0.4
0.00028 @ 25°C
0.00105
1000 @ 25°C
10 @ 150°C
Dow Corning
200.10
#5012
–35°C (v)**
165°C (fl, cc)
165°C
10 @ 25°C
3 @ 135°C
0.934 @ 25°C
0.43 @ 40°C
0.45 @ 100°C
0.482 @ 200°C
0.00032 @ 25°C
0.00108
1000 @ 25°C
50 @ 150°C
Dow Corning
200.20
#5013
7°C (v)
230°C (fl, cc)
230°C
20 @ 25°C
0.949 @ 25°C
0.370 @ 40°C
0.393 @ 100°C
0.420 @ 200°C
0.00034 @ 25°C
0.00107
1000 @ 25°C
50 @ 150°C
Dow Corning
200.50
Silicone Oil #5014
25°C (v)
280°C (fl, cc)
280°C
20 @ 25°C
0.96 @ 25°C
0.4
0.00037 @ 25°C
0.00104
1000 @ 25°C
50 @ 150°C
Dow Corning 550
#5016
70°C (v)
232°C (fl, cc)
300°C (fl, oc)
232°C
50 @ 70°C
10 @ 104°C
1.07 @ 25°C
0.358 @ 40°C
0.386 @ 100°C
0.433 @ 200°C
0.00035 @ 25°C
0.00075
100 @ 25°C
1 @ 150°C
Dow Corning 710
#5017
80°C (v)
302°C (fl, oc)
302°C
50 @ 80°C
7 @ 204°C
1.11 @ 25°C
0.363 @ 40°C
0.454 @ 100°C
0.505 @ 200°C
0.00035 @ 25°C
0.00077
100 @ 25°C
1 @ 150°C
Dow Corning
210-H
Silicone Oil
66°C (v)
315°C (fl, oc)
315°C
50 @ 66°C
14 @ 204°C
0.96 @ 25°C
0.34 @ 100°C
0.0003
0.00095
100 @ 25°C
1 @ 150°C
Heat Transfer Salt
#5001
145°C (fr)
530°C
NONE
34 @ 150°C
6.5 @ 300°C
2.4 @ 500°C
2.0 @ 150°C
1.9 @ 300°C
1.7 @ 500°C
0.33
0.0014
0.00041
1.7
Ω
/cm
3
*Limiting Factors — b - boiling point e - high evaporation fl - flash point fr - freeze point v - viscosity — Flash point test
oc = open cup cc = closed cup
**Very low water solubility, ice will form as a slush from condensation below freezing.
Table 2
Table of Various Fluids and Their Properties
