LUBRICANT LUBRICANT &&

LUBRICATIONLUBRICATION

Crude Oil

Gasoline Kerosene Fuel Oil Oil Lubricant

H.C. Oil

Wax AromaticS & N

Contaminant

Hydrocracking

Catalitic Treatment

1000-3000 psi

430 – 550 C

H.C. Lube Oil

Additives

n-Parafin

Chemical Additives

1. Oxidation Inhibitor (O)

2. Rust Inhibitor (R)

3. Anti Wear & Extreme Pressure (EP)

4. Friction Modifier (W )

5. Detergent & Dispersant (D)

6. Pour-point Depressant (P)

7. Foam Inhibitor (F)

8. Viscosity Index Improver (VI)

Tabel hal. 25

Synthetic Oil

Hydrocarbon Poly Alpha-Olefins (PAOs)

Viscosity

Y

X

UF

Newtonian Fluid = dU/dy

h

F/A = U/h = (F/A) / (U/h)

= Shear Stress / Shear Rate

= Absolute Viscosity (Dyne.s/cm2 - Poise)

v = Kinematic Viscosity

v = / (Stoke – St)

(cSt – mm2/s)

= Density (grm/cm3)

Saybolt Universal Seconds (SUS)

SUS

SUSvityVisKinematic

180)(22.0)(cos

Tabel hal, 28

Viscosity vs Temperature

log. log (v + 0.7) = A – B log T

T = Temperature

v = Kinematic viscosity

A, B = Constants – given oil

T

BA

''log

Tbea /''

Vogel Equation

)( refTTref e

= Viscosity-Temp. Coeff

12

12 )/ln(

TT

Viscosity Index

HL

ULVI

L = Viscosity (40C) dari zero-VI oil

H = viscosity (40C) dari 100-VI oil

U = vsicosity (40C) dari Unkown-oil

ASTM

Y

UHN

NantiVI

log

loglog

10000715.0

1)log(

Y = Viscosity cSt(100 C) unkown oil

Viscosity vs Pressure

P

e P

0

0

ln

= Pressure-viscosity Coeff.

Roelands Equation

Z

C

P

1)2.1(log2.1log 0

C = konstanta – unit (196.1 MPa atau 28440 psi)

Z = 0.6 = 0.4 – 0.8 synthetic oil

)864.0885.0(

)2.1)log(log

)2.1)log(log

81.7

4040

100100

4040

405.1

10040

HF

H

H

FHHz