engine oil analysis - georgia department of transportation - aashto … · oil analysis for...
TRANSCRIPT
Agenda
1. Purpose and Objective
2. Engine Oil
3. Experimental Program
4. Baseline Oil Analyses
5. Analysis Program
6. Analysis Results
7. Recommendations
1. Purpose and Objective
Purpose
Understand how (fast) engine oil changes over time to investigate the potential for extending drain intervals.
Objective
Push the drain interval limit while maintaining sufficient oil quality to NOT endanger the engine.
2. What is engine oil?
A formulated blend of base oil and various additives
Base oil (75 to 99% by volume)• Petroleum based derived from crude – conventional or mineral
• Polyalphaolefin (PAO) synthesized hydrocarbon – synthetic oil
• Mixture of the two – synthetic blend oil
2. What is engine oil?
Additives (1 to 25% by volume)• Surface Protection
• Anti-wear
• Corrosion Inhibitor
• Detergent
• Dispersant
• Friction Modifiers
• Performance
• Pour Point Depressant
• Seal Swell Agent
• Viscosity Modifier
• Protective
• Antifoaming Agent
• Antioxidant
2. What happens as oil ages?
1. Physical Change
• Viscosity increase – soot contamination through blow-by
• Viscosity decrease – mechanical degradation (molecular shearing) or dilution
• Corresponding density changes
2. What happens as oil ages?
2. Chemical Change• Oxidation – reaction of base oil with oxygen
• Additive Depletion – decomposition or mass transfer
• Thermal and/or Compressive Heating
3. Contamination• Water
• Dirt
• Fuel
• Soot
• Glycol
• Wear metals
Changes are not independent One source – if left long enough –
may have a domino effect
3. Analysis Equipment
• Benchtop analysis to avoid time delay in results
• OSA4 TruckCheck ($50k) and Spectro Scientific MicroLab 30 ($80k)• Chemical analysis by infrared spectrometer – TBN, oxidation,
nitration, water, soot, glycol
• Viscosity (40 and 100C) by Kinematic Viscometer
• Metals analysis by Optical Emission Spectrometer
• Perform ~3 analyses per hour
• Consumables• CheckFlush fluid
• Standardization fluids
3. Threshold Oil Parameters
• Ideally set specific to each engine/equipment type
• Sump capacity
• Operating conditions
• General min/max values applicable across the fleet
• Tended towards conservative values
• Set in consultation with Mr. Diego Navarro
• Used to trigger an oil change
3. Threshold Oil Parameters
Full list of thresholds in project report
Key Parameters
1. TBN: 4 mg KOH/g
2. Viscosity: 12.5 – 16.3 cSt (40 wt oil)
3. Silicon: 40 ppm (10 ppm if dirt)
4. Aluminum: 15 ppm (with Si)
5. Iron: 100 ppm
6. Potassium and Sodium (glycol): 50 ppm both
Agenda
1. Purpose and Objective
2. Engine Oil
3. Experimental Program
4. Baseline Oil Analyses
5. Analysis Program
6. Analysis Results
7. Recommendations
4. Baseline Oil Analyses
Three oil types
1. Conoco HD Fleet Supreme conventional 15W-40
2. Xtreme Fleet synthetic blend 15W-40
3. Shell Rotella T6 full synthetic 5W-40
Analyzed samples of fresh oil and compared with manufacturer published values
1. Conventional: 18 bulk tank samples
2. Synthetic blend: 24 bulk tank samples
3. Synthetic: 30 bulk tank & 12 retail samples
4. Baseline Oil Analyses
Conoco HD Fleet
SupremeConventional 15W-40
Xtreme FleetSynthetic Blend 15W-40
Shell Rotella T6Full Synthetic 5W-40
Published
Avg.
Measured Published
Avg.
Measured Published
Avg. Measured
Div 10
Bulk Tank
Div 3
Bulk Tank Retail A Retail B
Viscosity, 40C
(cSt)115 N/A 116.4 100.2 87 N/A 81 N/A N/A
Viscosity, 100C
(cSt)15.2 14.99 15.8 13.9 14.2 12.84 13.2 12.98 13.61
Viscosity Index 135 N/A 144 141 169* N/A 165 N/A N/A
TBN
(mg KOH/g)9.5 9.33 10.1 8.61 10.6 9.53 9.53 9.45 9.38
* Value not published, calculated value
5. Analysis Program
2014-16 Charlotte Area
• Analyzed oil from all machines in 4 classes
• 200 hr / 5,000 mile interval
• 47 total machines
• Selected 3 to 4 machines in each class for extended drain intervals
• Ultimately put all IMAP trucks on extended intervals
• Conventional & synthetic oils
2016-18 Wilmington Area
• 4 equipment classes
• 13 total machines
• 3 to 4 machines in each all for extended intervals
• Included Navistar DT466 engine to continue study
• 3 additional engines to add to the previous study
• Blend & synthetic oils
5. Studied Equipment
2014 – 2016 Charlotte Area (Div. 10)
Class 0209International 7300
Navistar DT466 7.6L I6
Conventional
Class 0210Ford F350
Powerstroke 6.4L V8
Powerstroke 6.7L V8
Rotella T6 synthetic
5. Studied Equipment
2014 – 2016 Charlotte Area (Div. 10)
Class 0303New Holland T6030
NH 6.7L 6-cylDeere 6420
Deere 4.5L 4-cyl Conventional
Class 0311Deere 7600
Deere 6.8L 6-cyl
Deere 6140M
Deere 4.5L 4-cyl
Conventional
5. Studied Equipment
2016 – 2018 Wilmington Area (Div. 3)
Class 0205
International 7300Navistar DT466 6.7L I6
2 using Rotella T6 synthetic
2 using synthetic blend
Class 0212
Mack GU713MP7-395C 11L I6
Synthetic blend
5. Studied Equipment
2016 – 2018 Wilmington Area (Div. 3)
Class 0314
JCB 3C15JCB 444 4.4L 4-cyl
Synthetic blend
Class 1854
Hyundai R140LC-7AMitsubishi D04FC-TAA 4.2L 4-cyl
Synthetic blend
Agenda
1. Purpose and Objective
2. Engine Oil
3. Experimental Program
4. Baseline Oil Analyses
5. Analysis Program
6. Analysis Results
7. Recommendations
6. Analysis Results
Equipment
No. of Samples
Analyzed
No. of Machines
Sampled
0209 Crew Cab Chassis 178 13
0210 IMAP Truck 358 12
0303 Mowing Tractor 162 8
0311 Sideboom Mowing Tractor 252 14
0205 Single-Axle Dump 3 1
0212 Tandem-Axle Dump 42 3
0314 Backhoe Loader 23 3
1854 Excavator 21 3
Total 1,039 57
Collected 3 samples (150 ml) at pre-determined intervals and averaged the results
6. Analysis Results
• TBN key to chemical change
• Time (use) dependent
• Viscosity decrease due to fuel dilution
• Specific to engine type
• Contamination was not an issue (water, glycol, soot)
• Very little wear metals produced
• Copper passivation
• Isolated engine issues
6. TBN – Conventional Oil
• Tractors performed similarly
• TBN is use dependent
• TBN decrease 0.4 per 100 hrs
• Threshold at 1350 hrs
y = -0.0039x + 9.37
R² = 0.4263
0
2
4
6
8
10
12
0 100 200 300 400 500
To
tal
Ba
se N
um
ber
(m
g K
OH
/g)
Oil Age (hrs)
0303 & 0311 Mowing Tractors
0311
0303
• TBN is not use dependent
• TBN remained unchanged to 11k miles
y = -0.00002x + 9.22
R² = 0.0171
0
2
4
6
8
10
12
0 2,000 4,000 6,000 8,000 10,000 12,000
To
tal
Ba
se N
um
ber
(m
g K
OH
/g)
Oil Age (miles)
0209 Crew Cab Chassis
0209
215-6377
6. TBN – Synthetic Blend
Preliminary Results
y = -0.0044x + 9.1993
R² = 0.3586
0
2
4
6
8
10
12
0 100 200 300 400
To
tal
Ba
se N
um
ber
(m
g K
OH
/g)
Oil Age (hrs)
0314 Backhoes and 1854 Excavators
0314
1854
y = -0.00034x + 9.83
R² = 0.97367
y = -0.00040x + 9.70
R² = 0.96948
0
2
4
6
8
10
12
0 2,000 4,000 6,000 8,000 10,000 12,000
To
tal
Ba
se N
um
ber
(m
g K
OH
/g)
Oil Age (miles)
0212 Tandem Axle Dump Trucks
• ~0.4 decrease per 100 hrs
• Threshold at ~1200 hrs
• ~0.4 decrease per 1,000 miles
• Threshold at ~14k miles
6. TBN – Synthetic
• More variable
• Faster (?) to threshold
• Fairly consistent / predictable
• 12k miles to TBN of 4
y = -0.0004x + 9.16
R² = 0.5807
0
2
4
6
8
10
12
0 2,000 4,000 6,000 8,000 10,000 12,000 14,000
To
tal
Ba
se N
um
ber
(m
g K
OH
/g)
Oil Age (miles)
0210 IMAP Trucks - 6.4 L
y = -0.0004x + 9.10
R² = 0.824
0
2
4
6
8
10
12
0 2,000 4,000 6,000 8,000 10,000 12,000 14,000
To
tal
Ba
se N
um
ber
(m
g K
OH
/g)
Oil Age (miles)
0210 IMAP Trucks - 6.7 L
6. TBN – Conv. vs Synthetic
One oil drain in two IMAP trucks with 6.7L engine
0
2
4
6
8
10
12
0 2,000 4,000 6,000 8,000 10,000 12,000 14,000
Tota
l B
ase
Nu
mb
er (
mg K
OH
/g)
Oil Age (miles)
Conventional
Synthetic
6. Viscosity – Conventional Oil
• 0311 might trend upward
• All results within specification
• Some low viscosity
• Not time (use) dependent
6
8
10
12
14
16
18
0 2,000 4,000 6,000 8,000 10,000 12,000
Vic
osi
ty a
t 1
00
C (
cSt)
Oil Age (miles)
0209 Crew Cab Chassis
0209
215-6377
6
8
10
12
14
16
18
0 100 200 300 400 500
Vic
osi
ty a
t 1
00
C (
cSt)
Oil Age (hrs)
0303 & 0311 Mowing Tractors
0311
0303
6. Viscosity – Synthetic Blend
Preliminary Results
6
8
10
12
14
16
18
0 100 200 300 400
Vis
cosi
ty a
t 1
00
C (
cSt)
Oil Age (hrs)
0314 Backhoes and 1854 Excavators
0314
1854
6
8
10
12
14
16
18
0 2,000 4,000 6,000 8,000 10,000 12,000
Vis
cosi
ty a
t 1
00
C (
cSt)
Oil Age (hrs)
0212 Tandem Axle Dump Trucks
6. Viscosity – Synthetic
• Low viscosity at 1k miles
• Fuel dilution (known to the 6.4L engine)
• At the SAE min for 40 wt oil
• Very consistent
6
8
10
12
14
16
18
0 2,000 4,000 6,000 8,000 10,000 12,000 14,000
Vis
cosi
ty a
t 1
00
C (
cSt)
Oil Age (miles)
0210 IMAP Trucks - 6.4 L
6
8
10
12
14
16
18
0 2,000 4,000 6,000 8,000 10,000 12,000 14,000
Vis
cosi
ty a
t 1
00
C (
cSt)
Oil Age (miles)
0210 IMAP Trucks - 6.7 L
6. Oil Contamination
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
0 100 200 300 400 500
Co
nta
min
an
t C
on
ten
t (%
)
Oil Age (hrs)
0311 Sideboom Mowing Tractors
Soot (3% max)
Water (0.5% max)
Glycol (0% max)
6. Wear Metals – 0303 Tractors
0
5
10
15
20
0 50 100 150 200 250 300
Alu
min
um
(p
pm
)
Oil Age (hrs)
0
20
40
60
80
100
120
0 50 100 150 200 250 300
Iro
n (
pp
m)
Oil Age (hrs)
0
10
20
30
40
50
60
70
0 50 100 150 200 250 300
Co
pp
er (
pp
m)
Oil Age (hrs)
0
2
4
6
8
10
12
0 50 100 150 200 250 300
Ch
rom
ium
(p
pm
)
Oil Age (hrs)
6. Copper – New Tractors
0
10
20
30
40
50
60
70
0 100 200 300 400 500 600
Cop
per
(p
pm
)
Tractor Age (hrs)
838-0311
838-0312
838-0313
838-0314
7. Recommendations
Class Engine
Recommended
Drain Interval Comments
0209 Navistar DT466 10,000 miles Likely longer, need additional data
02106.4L 5,000 miles Viscosity / Fuel Dilution
6.7L 10,000 miles Consider conventional oil
0303
0311All 500 hrs Likely longer, need additional data
Opportunity to extend drain intervals without significant danger of unacceptable oil quality
7. Recommendations
Class Engine (Sump) Count
Avg Ann.
Use
Est. Cost
per Oil
Change
Estimated Annual Savings
Oil Changes
per Machine
Annual
Cost
Annual
Oil (gals)
0209 Navistar DT466 (30) 164 10,187 mi $ 250 1 per yr $ 41,000 1,230
0210
PwrStrk 6.4L (15) 22 28,040 mi $ 170 None $ 0 0
PwrStrk 6.7L (13) 55 33,014 mi $ 170 3 per yr $ 28,050 536
0303
NH 6.7L (22) 64 216 hrs $ 300 None $ 0 0
Deere 4.5L (16) 54 302 hrs $ 300 1 per yr $ 16,200 216
0311
Deere 6.8L (24) 43 420 hrs $ 300 1 per yr $ 12,900 258
Deere 4.5L (16) 20 564 hrs $ 300 1 per yr $ 6,000 80
NH6.7L (22) 55 387 hrs $ 300 1 per yr $ 16,500 302
Estimated Annual Savings $ 120,650 2,622
Take Aways
1. Benchtop analyzers costly, but work well
2. Conventional oil performed very well
3. Engine influenced oil performance
4. Chemical change the driver
5. Extended drain intervals worth considering
6. Potential for significant savings
