Unlike the Turbomolecular Pump the Diffusion Pump recquires a working fluid to move gas molecules. This fluid is commonly reffered to as an oil, due to the fluids resembling oils in feel and consitency. Below is a list of various Diffusion Pump Oils and their physical properties.
Dow Corning
Silicone Oils
Physical Properties
| Name |
Vapor Pressure |
Viscosity 25°C |
Boiling Point 0.5 torr |
Flashpoint |
Condensation Point |
Density
|
| DC 702[1] |
1 x 10⁻⁶ Torr |
45 mm²/s |
180°C |
≥ 193°C |
°C |
1070 kg/m³
|
| DC 704[2] |
2 x 10⁻⁸ Torr |
39 mm²/s |
215°C |
221°C |
°C |
1070 kg/m³
|
| DC 705[3] |
3 x 10⁻¹⁰ Torr |
175 mm²/s |
245°C |
243°C |
°C |
1090 kg/m³
|
Kurk J. Lekser Corporation
Silicone Oils
Physical Properties
| Name |
Vapor Pressure |
Viscosity 25°C |
Boiling Point 0.06 torr |
Flashpoint |
Condensation Point |
Density
|
| KJLC 704[4] |
8.4 x 10⁻⁸ Torr |
46 mm²/s |
223°C |
220°C |
°C |
1100 kg/m³
|
| KJLC 704-T[5] |
8.4 x 10⁻⁸ Torr |
37 mm²/s |
210°C |
220°C |
°C |
1070 kg/m³
|
| KJLC 705[6] |
3 x 10⁻¹⁰ Torr |
165-185 mm²/s |
245°C |
243°C |
°C |
1090 kg/m³
|
VacOil
Silicone Oils
Physical Properties
| Name |
Vapor Pressure |
Viscosity 25°C |
Flashpoint |
Condensation Point |
Density
|
| DP Grade 704[7] |
6.65 x 10⁻⁸ Torr |
36 mm²/s ± 4 mm²/s |
≥ 210°C |
≥ -35°C |
1050 ∼ 1080 kg/m³
|
Leybold
Hydrocarbon Oils
Physical Properties
| Name |
Vapor Pressure |
Viscosity 25°C |
Boiling Point 0.06 torr |
Flashpoint |
Condensation Point |
Density
|
| Diffilen Leicht |
|
mm²/s |
°C |
°C |
°C |
kg/m³
|
| Diffilen |
|
mm²/s |
°C |
°C |
°C |
kg/m³
|
| Diffilen Extra |
|
mm²/s |
°C |
°C |
°C |
kg/m³
|
| Diffilen Ultra |
|
mm²/s |
°C |
°C |
°C |
kg/m³
|
| LVO 500[8] |
4 · 10⁻⁹ mBar |
mm²/s |
°C |
> 250 °C |
°C |
868 kg/m³
|
| LVO 521[9] |
6 · 10⁻⁶ mBar |
mm²/s |
°C |
196 °C |
°C |
885 kg/m³
|
Silicone Oils
Physical Properties
| Name |
Vapor Pressure |
Viscosity 25°C |
Boiling Point 0.06 torr |
Flashpoint |
Condensation Point |
Density
|
| LVO 521[10] |
3 · 10⁻¹⁰ mBar |
mm²/s |
°C |
240 °C |
°C |
1095 kg/m³
|
Santovac
Polyphenyl Ether Oils
Physical Properties
| Name |
Vapor Pressure |
Viscosity 38°C |
Viscosity 90°C |
Viscosity 260°C |
Boilding Point 0.5 Torr |
Flashpoint |
Condensation Point |
Density
|
| Santovac 5[11] |
4 x 10⁻¹⁰ Torr |
363 mm²/s |
13.1 mm²/s |
1.2 mm²/s |
275 °C |
288°C |
|
1198 kg/m³
|
Apiezon
Hydrocarbon Oils
Physical Properties
| Name |
Vapor Pressure |
Viscosity 20°C |
Viscosity 40°C |
Flashpoint |
Pour Point |
Density
|
| AP201[12] |
4 x 10⁻⁶ Torr |
76 mm²/s |
22 mm²/s |
196°C |
-30°C |
885 kg/m³
|
Cambridge Mill Products
Silicone Oils
Physical Properties
| Name |
Vapor Pressure |
Viscosity 25°C |
Flashpoint |
Density
|
| CMP 704[13] |
10⁻⁶ to 10⁻⁸ Torr |
mm²/s |
221°C |
1070 kg/m³
|
Ideal Vacuum Products
Silicone Oils
Physical Properties
| Name |
Vapor Pressure |
Viscosity 25°C |
Boiling Point |
Flashpoint |
Density
|
| IVP 702[14] |
|
45 mm²/s |
180°C |
193°C |
1090 kg/m³
|
| IVP 704[15] |
|
39 mm²/s |
215°C |
221°C |
1065 kg/m³
|
| IVP 705[16] |
|
175 mm²/s |
245°C |
243°C |
1090 kg/m³
|
Varian
Polyphenyl Ether Oils
Physical Properties
| Name |
Vapor Pressure |
Viscosity 38°C |
Viscosity 90°C |
Viscosity 260°C |
Boilding Point 0.5 Torr |
Flashpoint |
pour Point |
Density
|
| Neovac SY [17] |
|
mm²/s |
mm²/s |
mm²/s |
275 °C |
287°C |
40°F |
1195 - 1201 kg/m³
|
References