Scrapedown Limited Presentation

1.

Analysis of Scrapedown Cylinder Oils
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2. Scrapedown Cylinder Oils - Conclusions of Feedrate Study

Scrapedown Cylinder Oils Conclusions of Feedrate Study
• Most important properties
1 Iron - Clear indicator of wear
2 TBN - Best indicator for feedrate optimization
3 PQ - Safeguard for monitoring non-corrosive wear
4 Viscosity - Monitors excessive system oil contamination
• Important secondary properties
– Vanadium - Helps identify excessive blowby
– Phosphorus - Monitors system oil contamination
• Analytical Ferrography
– Wear type analysis is useful
– Wear Ratings are semi-quantitative and not very useful
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3. Scrapedown Cylinder Oils - Analysis of Iron

Scrapedown Cylinder Oils Analysis of Iron
800
700
600
500
Iron
(M1311)
ppm
400
300
200
100
0
0
100
200
300
400
500
600
700
800
Iron (D5185), ppm
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4. Scrapedown Cylinder Oils - TBN Analysis

Scrapedown Cylinder Oils TBN Analysis
• TBN is measured by conventional ASTM D2896
(potentiometric titration with perchloric acid).
• TBN is an excellent indicator for how close one is
to high wear situations.
– Low TBN indicates the potential for excessive corrosive
wear
– High TBN indicates the potential for excessive ring
deposits resulting in adhesive wear
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5. Scrapedown Cylinder Oils - Iron Correlation with TBN

Scrapedown Cylinder Oils Iron Correlation with TBN
2000
1500
Iron
ppm
1000
500
0
0
10
20
30
40
50
60
70
TBN
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6. Scrapedown Cylinder Oils - Margin of Safety

Scrapedown Cylinder Oils Margin of Safety
1000
800
600
Iron
ppm
400
Margin of
Safety
200
0
0
10
20
30
40
50
60
70
TBN
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7. Scrapedown Cylinder Oils - PQ versus TBN

Scrapedown Cylinder Oils PQ versus TBN
400
One High PQ Data Point Removed
350
300
250
PQ
200
150
100
50
0
0
10
20
30
40
50
60
70
TBN
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8. Scrapedown Cylinder Oils - Optimum Feed Rate

Scrapedown Cylinder Oils Optimum Feed Rate
• To determine the optimum feedrate, the following
issues need to be addressed:
– What is the range of engine loads and what is typical?
– What is the range of fuel sulfur levels and what is
typical?
– What are the worst wear conditions for this engine?
• High load / high sulfur fuel
• Low load / high sulfur fuel
• Low sulfur fuel
– Develop a plan for feedrate reduction/increase
• Recommend 0.05 g/BHPh intervals for decreases
– Determine a failsafe feedrate for the worst of conditions
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9. Scrapedown Cylinder Oils - Optimization Target

Scrapedown Cylinder Oils Optimization Target
1000
800
600
Iron
ppm
400
Margin of
Safety
200
0
0
10
20
30
40
50
60
70
TBN
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10. Scrapedown Cylinder Oils - Analytical Ferrography

Scrapedown Cylinder Oils Analytical Ferrography
Analytical Ferrography
• Monitors sizes and
types of wear debris
present in oils
• Estimates relative
amounts of each wear
type (Wear Rating)
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11. Scrapedown Cylinder Oils - Analytical Ferrography Results

Scrapedown Cylinder Oils Analytical Ferrography Results
• Typical samples contain:
– Normal rubbing wear
– Iron oxides
– Corrosive wear
– Some fatigue wear
Iron easily measured
by ICP-AES
• Less frequently observed are significant amounts
of:
– Severe sliding wear
– Cutting wear
– Spall particles
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12. Scrapedown Cylinder Oils - Analytical Ferrography Results

Scrapedown Cylinder Oils Analytical Ferrography Results
• Typically Found
– Normal Rubbing Wear
– Corrosive Wear
– Rust and Dark Iron Oxides
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13. Scrapedown Cylinder Oils - Analytical Ferrography Results

Scrapedown Cylinder Oils Analytical Ferrography Results
• Often Found
– Fatigue Wear
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14. Scrapedown Cylinder Oils - Analytical Ferrography Results

Scrapedown Cylinder Oils Analytical Ferrography Results
• Not Frequently Found
– Cutting Wear
– Severe Sliding Wear
– Spheres
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15. Scrapedown Cylinder Oils - Analytical Ferrography Results

Scrapedown Cylinder Oils Analytical Ferrography Results
• Wear types can be useful to help identify the
primary wear mechanism.
• Wear Ratings do not adequately distinguish low
from high wear.
– Subjective
– No standard reference has been established
– Scrapedown oils contain many wear particles and wear
particle types
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