anticipated service – normal service or heavy service. The
ambient temperature determines the required oil viscosity.
Consider the full range of high and low ambient temperatures
at the compressor’s location when selecting an oil. It may
be necessary to use an ISO 100 in summer and an ISO
68 in winter. Synthetic oils generally have a wider ambient
temperature range due to their higher viscosity index.
For the purpose of selecting a suitable crankcase oil for
a Corken compressor, normal and heavy service are
defined below.
Normal Service
“Normal service” can be defined as anything that is not
considered “heavy service” as described below.
Common examples of “normal service” applications:
• LPG liquid transfer (intermittent duty)
• Ammonia liquid transfer (intermittent duty)
• Most tank evacuation applications
Conventional mineral based oils have been used
successfully for many years in these services.
Heavy Service
“Heavy Service” is defined as an application where the
compressor is subject to any one (or more) of the following:
• Continuous duty service (several hours each day or more)
• Compressor consistently loaded at or near its maximum
horsepower rating
• Compressor speed is at or near its maximum speed rating
• Services with a “wet” gas such as natural gas with high
content of heavy hydrocarbons such a butane, pentane, etc.
• Services dealing with low vapor pressure hydrocarbons
(such as butane unloading in winter) where condensation
in the gas can result in dilution of the crankcase oil
• Compressors operating at high or low temperature extremes
Synthetic oils are recommended for “heavy” services.
Crankcase Oil Recommendations (Except Ammonia Service)
Normal Service
Ambient Temperature
1
Oil Product
Oil Type
2
Viscosity ISO
3
Viscosity Index
3
Pour Point
3
40 to 100°F (4 to 38°C)
Mobil DTE 10 Excel 100
C
100
127
-27°F (-33°C)
Mobil Rarus 427
C
100
100
16°F (-9°C)
Phillips 66 Gas Compressor Oil
C
100
102
-20°F (-29°C)
Chevron Regal R&O
C
100
97
5°F (-15°C)
Sunoco Sunvis 900
C
100
95
-15°F (-26°C)
10 to 65°F (-12 to 18°C)
Mobil DTE 10 Excel 68
C
68
156
-38°F (-39°C)
Mobil DTE Heavy Medium
C
68
95
5°F (-15°C)
Phillips 66 Premium Gas Compressor Oil
B
68
133
-27°F (-33°C)
Chevron Regal R&O
C
68
99
-11°F (-24°C)
Sunoco Sunvis 900
C
68
104
-21°F (-29°C)
Heavy Service
10 to 100°F (-12 to 38°C) Mobil SHC 627
4
S
100
162
-49°F (-45°C)
Royal Purple Synfilm NGL 100
S
100
130
-44°F (-42°C)
Dyna-Plex 21C Synzol CO ISO 100
S
100
132
-49°F (-45°C)
-20 to 90°F (-29 to 32°C) Mobil SHC 626
4
S
68
165
-59°F (-51°C)
Royal Purple Synfilm NGL 68
S
68
132
-76°F (-60°C)
Crankcase Oil Recommendations (Ammonia Service Only)
Normal Service
Ambient Temperature
1
Oil Product
Oil Type
2
Viscosity ISO
3
Viscosity Index
3
Pour Point
3
40 to 100°F (4 to 38°C)
Mobil Rarus 427
C
100
100
16°F (-9°C)
10 to 65°F (-12 to 18°C)
Phillips 66 Ammonia Compressor Oil
C
68
102
-27°F (-33°C)
Chevron Capella P68
C
68
96
-44°F (-42°C)
Mobil Rarus 426
C
68
105
16°F (-9°C)
Heavy Service
10 to 100°F (-12 to 38°C) Mobil Gargoyle Arctic SHC 228
5
S
100
147
-43°F (-45°C)
Royal Purple Uni-Temp 100
S
100
124
-53°F (-47°C)
-20 to 90°F (-29 to 32°C) Mobil Gargoyle Arctic SHC 226E
5
S
68
136
-58°F (-50°C)
Royal Purple Uni-Temp 68
S
68
118
-51°F (-46°C)
1
Consult Corken for oil recommendations in very hot climates—ambient temperatures consistently above 100°F (38°C).
2
Oil type: C=Conventional, S=Synthetic, B=Conventional/Synthetic blend
3
Information available from oil manufacturers at the time of publication.
4
Mobil SHC oils are synthetic oils which require that the crankcase be flushed of residual mineral oil.
5
Mobil Gargoyle Arctic SHC oils are synthetic oils which require that the crankcase be flushed of residual mineral oil.
10
