12.4.2.5
Interpretation of the oil analysis for a cylinder oil with BN 40 or higher
For a cylinder oil with BN 40 or higher, refer to
for the interpretation of the drain oil
analysis results.
Fig 12-3
Interpretation of the oil analysis for cylinder oils with BN 40 or higher
0
0
100
200
300
400
500
600
700
10
20
30
40
50
60
70
00115
Residual BN in mg KOH/g
BN and/or
Iron alert area
BN and/or
Iron alert area
Iron alert area
Danger area. Do not operate in this area
Safe area
T
otal iron (Fe) in mg/kg
NOTE:
There are smooth transitions between the different areas shown in
Use the data that follows for an interpretation of the oil analysis:
•
Safe area
If the residual BN is between BN 25 and BN 50, and the iron (Fe) content is less than
200 mg
⁄
kg, the operation is thought to be safe.
•
Alert area
The lower alert range for piston underside residual BN is between BN 10 and BN 25. In this
area there might be a risk of corrosion. This is because the base additives could be not
sufficient to neutralize the sulphuric acid from the fuel.
The upper alert limit for piston underside residual BN is above BN 50. Higher values can
cause damage to the piston running system. This is because the alkalinity of the cylinder
oil gets too high. This operation can cause excessive deposits on the piston. If there are
excessive deposits on the piston, the lubricant film can break down and thus cause wear of
the piston running system.
The alert range for iron (Fe) content in the drain oil is between 200 mg/kg and 500 mg/kg.
X52
AA00-0000-00AAA-030G-A
Operation Manual
Cylinder oils
Winterthur Gas & Diesel Ltd.
- 458 -
Issue 002 2018-11
