F
OR
M
ODELS
: JGI, JGM, JGN, JGP
AND
JGQ
S
ECTION
4 L
UBRICATION
PAGE 4-4
•
Higher wax content
•
Viscosity Index, greater than 90
•
Pour point around 25°F (-4°C)
•
This is the most common mineral oil base stock.
N
APTHENIC
O
ILS
•
Solvent refined or hydro-treated
•
South Louisiana crude
•
Lower Wax content
•
Viscosity Index, less than 80
•
Lower pour point than paraffinic oils
•
Better additive solvency
Synthetic Lubricants
Synthetic lubricants are man-made materials with more consistent, controlled chemical
structures than petroleum lubricants. This improves predictability of viscosity and thermal
stability that results in much higher viscosity indexes than mineral oils. Additives can be
used to modify all the common lubrication characteristics to meet or exceed the perfor-
mance of mineral oils. There are three major types of synthetic fluids used for lubrication.
They are commonly referred to as PAO, Diester, and PAG.
NOTE: Most synthetic lubricants with the proper viscosity are acceptable for use in
the compressor frame. Check with your lubricant supplier or Ariel before
using ANY lubricant, if you have any questions about the applicability of the
lubricant in the frame.
P
OLYALPHAOLEFINS
(PAO) - S
YNTHESIZED
H
YDROCARBONS
•
Compatible with mineral oils
•
Most of the same properties as mineral oils
•
Requires additives to improve detergent action and improve seal compatibility
•
Soluble in hydrocarbon gases
•
High viscosity index, approximately 150
•
Low pour point
•
High flash point
O
RGANIC
E
STERS
- D
IESTERS
AND
P
OLYOLESTERS
•
Compatible with mineral oils, PAO and PAG oils
•
Incompatible with some rubbers (O-rings), plastics, and paints; compatible with Viton
•
Primarily used in air compressors
•
Leaves a soft carbon deposit when oxidized
•
Breaks down in water
•
Higher flash point than mineral oils
•
Can be made only to a viscosity of approximately (85-90 cSt at 40°C)
•
Higher viscosity achieved with additives or blending with heavier oils
•
Low viscosity index, approximately 70
