ISO Grade Viscosity downgradeISO Grade Viscosity downgrade

in a Bambury gearbox.in a Bambury gearbox.

Viscometric analysis.Viscometric analysis.

Mineral Oil ISO 320 vs PAO Oil ISO

220220

"The Polymer" taken from DeviantArt

ConsiderationsConsiderations

• OEM Recommendation: ISO 320 Mineral Gear• OEM Recommendation: ISO 320 Mineral Gear

Oil. VI 98.Oil. VI 98.

• Alternative: ISO 220 PAO Gear Oil. VI 155.

"The Polymer" taken from DeviantArt

10000.0

Viscosity cSt vs Temp °C

8000.0

9000.0

7000.0

8000.0

5000.0

6000.0

Vis

cosi

ty c

St

3000.0

4000.0

Vis

cosi

ty c

St

2000.0

3000.0

0.0

1000.0

0.0 10.0 20.0 30.0 40.0 50.0 60.0 70.0 80.0 90.0 100.00.0 10.0 20.0 30.0 40.0 50.0 60.0 70.0 80.0 90.0 100.0

Temperature °C

p Min ISO 320 p PAO ISO 220"The Polymer" taken from DeviantArt

Sometimes, tweaking the numbers (log10) helps to visualize the data.. I am Afraid this

case not much ☺… R2 might be better, but it is not too bad.case not much ☺… R2 might be better, but it is not too bad.

Log10 Viscosity vs Temp C

4

4.5

Log10 Viscosity vs Temp C

R² = 0.9713

3.5

Log

10

Vis

cosi

ty c

St

R² = 0.977

1.5

2

2.5

Log

10

Vis

cosi

ty c

St

0.5

1

1.5

0

0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95

log MIN log PAO Lineal (log MIN) Lineal (log PAO)log MIN log PAO Lineal (log MIN) Lineal (log PAO)

"The Polymer" taken from DeviantArt

Well, we can see in the graphs the different behaviour of the fluids when heat affects

them, at low temp, there is a wide gap between the lines, nevertheless, at highthem, at low temp, there is a wide gap between the lines, nevertheless, at high

temps, the curves get along each other. Let´s look at temps above 40 °C

Viscosity cSt vs Temp °C

350.0

400.0

Viscosity cSt vs Temp °C

250.0

300.0

350.0

Vis

cosi

ty c

St

150.0

200.0

Vis

cosi

ty c

St

0.0

50.0

100.0

0.0

40.0 50.0 60.0 70.0 80.0 90.0 100.0

Temperature °C

p Min ISO 320 p PAO ISO 220p Min ISO 320 p PAO ISO 220

"The Polymer" taken from DeviantArt

It is a little bit hard to tell any significative differences, don´t you agree? Let´s see now

what the logs say about:what the logs say about:

Log10 Viscosity vs Temp C

R² = 0.9892.4

2.6

Log10 Viscosity vs Temp C

R² = 0.9922

2.2

2.4

Log

10

Vis

cosi

ty c

St

1.6

1.8

Log

10

Vis

cosi

ty c

St

1

1.2

1.4

1

40 50 60 70 80 90 100

Temp °C

log MIN log PAO Lineal (log MIN) Lineal (log PAO)log MIN log PAO Lineal (log MIN) Lineal (log PAO)

"The Polymer" taken from DeviantArt

Conclusions:Conclusions:

• I think that an ANOVA exercise might clarify a little bit more if• I think that an ANOVA exercise might clarify a little bit more if

are there, or not, any significative differences between the 2

fluids @ operation temperature.fluids @ operation temperature.

• As stated before, if the additive chemistry (and the base fluid

nature) has been chosen, I certainly would trust in nature) has been chosen, I certainly would trust in

calculations like this to support a project involving an ISO

viscosity grade downgrade, from mineral to Synthetic in order

to achieve energy savings, without a negative compromise toto achieve energy savings, without a negative compromise to

the equipment remaining life.

• Any comment, shall be received gladly:• Any comment, shall be received gladly:

ariel.hernandez@terra.com.mx

"The Polymer" taken from DeviantArt