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 [1] [2] |
45 mm²/s [1] |
180°C [1] [2] |
≥ 193°C [1] |
°C |
1070 kg/m³ [1]
|
DC 703 [2] |
1 x 10⁻⁷ Torr [2] |
mm²/s |
200°C [2] |
°C |
°C |
1090 kg/m³ [2]
|
DC 704[3] |
2 x 10⁻⁸ Torr |
39 mm²/s |
215°C |
221°C |
°C |
1070 kg/m³
|
DC 705[4] |
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[5] |
8.4 x 10⁻⁸ Torr |
46 mm²/s |
223°C |
220°C |
°C |
1100 kg/m³
|
KJLC 704-T[6] |
8.4 x 10⁻⁸ Torr |
37 mm²/s |
210°C |
220°C |
°C |
1070 kg/m³
|
KJLC 705[7] |
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[8] |
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
|
Oil D |
|
mm²/s |
°C |
°C |
°C |
kg/m³
|
Oil E |
|
mm²/s |
°C |
°C |
°C |
kg/m³
|
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[9] |
4 · 10⁻⁹ mBar |
mm²/s |
°C |
> 250 °C |
°C |
868 kg/m³
|
LVO 521[10] |
6 · 10⁻⁶ mBar |
mm²/s |
°C |
196 °C |
°C |
885 kg/m³
|
Note: Oil D is similar to Apiezon A, and Oil E to Apiezon B. [2]
Silicone Oils
Physical Properties
Name |
Vapor Pressure |
Viscosity 25°C |
Boiling Point 0.06 torr |
Flashpoint |
Condensation Point |
Density
|
LVO 521[11] |
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[12] |
4 x 10⁻¹⁰ Torr |
363 mm²/s |
13.1 mm²/s |
1.2 mm²/s |
275 °C |
288°C |
|
1198 kg/m³
|
Apiezon
Formerly part of Shell Chemical Co. Ltd.[2]
Hydrocarbon Oils
Physical Properties
Name |
Vapor Pressure |
Viscosity 20°C |
Viscosity 40°C |
Boiling Point (at 10⁻² Torr) |
Flashpoint |
Pour Point |
Density |
Molecular Weight
|
A |
2 x 10⁻⁵ Torr[2] |
mm²/s |
mm²/s |
110°C[2] |
°C |
°C |
873.5 kg/m³[2] (at 15°C) |
414 Da[2]
|
B |
4 x 10⁻⁷ Torr[2] |
mm²/s |
mm²/s |
125°C[2] |
°C |
°C |
871 kg/m³[2] (at 15°C) |
468 DA[2]
|
C |
1 x 10⁻⁸ Torr[2] |
mm²/s |
mm²/s |
°C |
°C |
°C |
kg/m³ |
574 DA[2]
|
G |
1 x 10⁻⁶ Torr[2] |
mm²/s |
mm²/s |
°C |
°C |
°C |
kg/m³ |
|
BW |
1 x 10⁻⁷ Torr[2] |
mm²/s |
mm²/s |
°C |
°C |
°C |
kg/m³ |
|
AP201[13] |
4 x 10⁻⁶ Torr |
76 mm²/s |
22 mm²/s |
°C |
196°C |
-30°C |
885 kg/m³ |
|
Cambridge Mill Products
Silicone Oils
Physical Properties
Name |
Vapor Pressure |
Viscosity 25°C |
Flashpoint |
Density
|
CMP 704[14] |
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[15] |
|
45 mm²/s |
180°C |
193°C |
1090 kg/m³
|
IVP 704[16] |
|
39 mm²/s |
215°C |
221°C |
1065 kg/m³
|
IVP 705[17] |
|
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 [18] |
|
mm²/s |
mm²/s |
mm²/s |
275 °C |
287°C |
40°F |
1195 - 1201 kg/m³
|
Concolidated Electrodynamics Corporation
i-diamyl sebacate
Physical Properties
Name |
Vapor Pressure |
Viscosity 25°C |
Boiling Point |
Flashpoint |
Density |
Molecular Weight |
Formula
|
Amoil |
1 x 10⁻⁵ torr [2] |
mm²/s |
111°C [2] |
96°C[19] |
1019 kg/m³ [2] |
306.2 Da [2] |
C₆H₄(COOC₅H₁₁)₂ [2]
|
Amoil S |
1 x 10⁻⁶ torr [2] |
mm²/s |
111°C [2] |
118°C[19] |
925.1 kg/m³ [2] |
343.3 Da [2] |
C₈H₁₆(COOC₅H₁₁)₂ [2]
|
n-dibutyl phthalate
Physical Properties
Name |
Vapor Pressure |
Viscosity 25°C |
Boiling Point |
Flashpoint |
Density |
Molecular Weight |
Formula
|
Butyl phthalate |
3 x 10⁻⁵ torr [2] |
mm²/s |
85°C [2] |
94°C [19] |
1046.5 kg/m³ [2] |
278.1 Da [2] |
C₆H₄(COOC₄H₉)₂ [2]
|
n-dibutyl Sebacate
Physical Properties
Name |
Vapor Pressure |
Viscosity 25°C |
Boiling Point |
Flashpoint |
Density |
Molecular Weight |
Formula
|
Butyl Sebacate |
2 x 10⁻⁵[19] / 3 x 10⁻⁵ torr [2] |
mm²/s |
90°C [2] |
103°C[19] |
933 kg/m³ [2] |
314.3 Da [2] |
C₈H₁₆(COOC₄H₉)₂ [2]
|
d-2-ethyl hexyl phthalate
Physical Properties
Name |
Vapor Pressure |
Viscosity 25°C |
Boiling Point |
Flashpoint |
Density |
Molecular Weight |
Formula
|
Octoil |
3 x 10⁻⁷ torr[2] |
mm²/s |
122.5°C[2] |
125°C [19] |
910.3 kg/m³ [2] |
390.3 Da[2] |
C₆H₄(COOC₄H₁₇)₂[2]
|
Octoil S |
3 x 10⁻⁸ torr[2] |
mm²/s |
143.5°C[2] |
140°C[19] |
910.3 kg/m³ [2] |
426.3 Da[2] |
C₈H₁₆(COOC₄H₁₇)₂[2]
|
National Researach Corporation
chlorinated diphenyl
Physical Properties
Name |
Vapor Pressure |
Viscosity 25°C |
Boiling Point |
Flashpoint |
Density |
Molecular Weight |
Formula
|
Narcoil 10 |
3 x 10⁻⁴ torr [2] |
mm²/s |
°C |
°C |
1540 kg/m³ [2] |
326 Da [2] |
C₈H₁₆(COOC₄H₉)₂ [2]
|
d-2-ethyl hexyl phthalate
Physical Properties
Name |
Vapor Pressure |
Viscosity 25°C |
Boiling Point |
Flashpoint |
Density |
Molecular Weight |
Formula
|
Narcoil 20 |
3 x 10⁻⁸ torr[2] |
mm²/s |
143.5°C[2] |
°C |
910.3 kg/m³ [2] |
426.3 Da[2] |
C₈H₁₆(COOC₄H₁₇)₂[2]
|
Narcoil 40 |
3 x 10⁻⁷ torr[2] |
mm²/s |
122.5°C[2] |
°C |
910.3 kg/m³ [2] |
390.3 Da[2] |
C₆H₄(COOC₄H₁₇)₂[2]
|
Vacuum Industrial Applications Ltd.
chlorinated diphenyl
Physical Properties
Name |
Vapor Pressure |
Viscosity 25°C |
Boiling Point |
Flashpoint |
Density |
Molecular Weight |
Formula
|
Viacoil 10 |
3 x 10⁻⁴ torr [2] |
mm²/s |
°C |
°C |
1540 kg/m³ [2] |
326 Da [2] |
C₈H₁₆(COOC₄H₉)₂ [2]
|
d-2-ethyl hexyl phthalate
Physical Properties
Name |
Vapor Pressure |
Viscosity 25°C |
Boiling Point |
Flashpoint |
Density |
Molecular Weight |
Formula
|
Viacoil 20 |
3 x 10⁻⁸ torr[2] |
mm²/s |
143.5°C[2] |
°C |
910.3 kg/m³ [2] |
426.3 Da[2] |
C₈H₁₆(COOC₄H₁₇)₂[2]
|
Viacoil 40 |
3 x 10⁻⁷ torr[2] |
mm²/s |
122.5°C[2] |
°C |
910.3 kg/m³ [2] |
390.3 Da[2] |
C₆H₄(COOC₄H₁₇)₂[2]
|
Litton Engineering Labs.
Naphthene Oils
Physical Properties
Name |
Vapor Pressure |
Viscosity 25°C |
Boiling Point |
Flashpoint |
Density |
Molecular Weight |
Formula
|
Molecular Lubricant A |
1 x 10⁻⁶ torr [19] |
mm²/s |
°C |
°C |
873.5 kg/m³[19] |
Da |
|
Molecular Lubricant B |
1 x 10⁻⁷ torr [19] |
mm²/s |
°C |
°C |
871 kg/m³[19] |
Da |
|
Unknown Maker
Physical Properties
Name |
Vapor Pressure |
Viscosity 25°C |
Boiling Point |
Flashpoint |
Density |
Molecular Weight |
Formula
|
Myvane 20 |
torr |
mm²/s |
°C |
°C |
853 kg/m³ [2] |
Da |
|
References