When should I change my Oil?

Training Session, May 2011

Moussa ZIDOUNE, PhD, Chemist

Agenda

Lubricants

Test Methods

Reports and Interpretation

Conclusion

Mineral Oils: products of the distillation of crude petroleum, consiting of hydrocarbon chains: Paraffinic Naphtenic Aromatic

Synthetic Oils: oils made by chemical synthesis: Polyalphaolefins (PAO) Polyglycols (PAG) Ester oils Silicones

Semi-synthetic: blends of mineral oils with synthetic base oils

Vegetable Oils: made of soja, corn, castor, canola, cotton seed

Base Oils – General Classification

Classification of Lubricants by Additives

Additives are substances formulated for the improvement of the anti-friction, chemical and physical properties of base oils (mineral, synthetic, vegetable or animal), which results in enhancing the lubricant performance and extending the useful life of equipments.

Additives can make up to 30% of the lubricant.

Friction modifiers

Anti-wear

Extreme pressure (EP)

Anti-rust and corrosion inhibitors

Anti-oxidants

Detergents

Dispersants

Pour point depressants

Viscosity index enhancers

Anti-foaming agents

Engine oils

Gear oils

Hydraulic oils

Compressor oils

Transformer oils (insulating oils)

Turbine oils

Cutting fluids (coolants)

Classification of Lubricants by application

Functions of engine oil: Provision of stable oil film between sliding

surfaces

Provision of reliable engine operation in a wide temperature range.

Rust/corrosion protection of the engine parts

Cleaning sludge from the engine parts

Sealing piston ring - cylinder gap

Prevention of foaming

Cooling the engine parts

Engine Oils

Hydraulic Oils

Characteristics and properties Thermal and chemical stability Low compressibility Hydraulic stability Good lubrication Low foaming Emulsion capacity

Benefits of Oil Analysis

Reduction in maintenance costs Reduction in unscheduled downtime Reduction in unscheduled maintenance Reduction in machine power consumption Effective maintenance scheduling Improved equipment reliability. Maximization of oil change out intervals. Minimization of installation errors. Increase in equipment availability Reduction in disposal cost

Oil Analysis allows detection of:

Dirt and dust Water Glycol Fuel Soot Sulfates and nitrates Particles

Inductively Coupled Plasma (ICP) Direct Reading Ferrography (DR) Analytical Ferrography (AF) Filter Debris Analysis (PT)

Contamination Degradation of the lubricant Kinematic viscosity (VIS) Oxidation (FTIR) Acid number (AN) Base number (BN)

Wear

Test Methods

SP – Spectroscopy VIS – Viscosity FTIR – Infrared Analysis

TAN – Total Acid Number TBN – Total Base Number

PC – Particle count DR – Direct reading AF – Analytical Ferrography

FU- Fuel FP – Flash Point FIRE – Fire Point

GYL – Glycol Water -Tests

PT – Filter Analysis VCT – Varnish Test

Machine and Lubricant Condition

MACHINERY

AFDRPC

LUBRICANTS

FTIR VISTAN TBNWater, FU

SP

PCDR

SP - Analytical SpectroscopyDetects 22 elements (Particles <7 microns in size)

Wear Metals

Contamination- Boron, Sodium, Silicium, Potassium, Aluminum

Additives - Calcium, Phosphorus, Zinc, Magnesium, Barium

• Aluminum • Barium • Boron • Cadmium • Calcium • Chrome • Copper • Iron • Lead • Magnesium • Manganese • Molybdenum • Nickel • Potassium • Phosphorous • Silicium • Silver • Sodium • Tin • Titanium • Vanadium • Zinc

VIS - Viscosity

Measures the resistance to flow

Measured in centiStokes (cSt)

40 ◦C and/or 100 ◦C

Affected by: Oxidation Contamination

Change oil if the limit is > 20%, and Monitor trend if > 10%!

FTIR – Infrared Analysis

Fingerprint of the lubricant

Soot Level Oil Degradation

Oxidation Nitrates Sulfates

Contamination Glycol Water Fuel

Additives Level Mineral or Synthetic Base Oil Wavelength (cm-1)

Ab

sor b

ance

Water & glycol

Thickening Oil Degradation Products

New oil

Oxidation

4000

3500

3000

2500

2000

1500

1000

Total Acid Number(TAN) Total Base Number (TBN), ASTM D974 & ASTM D4739

TAN indicates oil oxidation or contamination by an acidic product. Acid number increases with oxidation Recommended for all industrial equipment

TBN measures the alkaline content of oil. Abnormal reduction indicates reduced acid neutralizing capacity. Recommended for engines

Effects of Water on Oil

Causes hydrolisis and oxidation

Generates acids

Thickening

Varnish and sludge

Contributes to foaming and emulsion

Effects of Water Contamination on the Machine

Water accelerates machine deterioration

Corrosion: water in oil confers their maximum destruction potential to acids

Loss of lubricating film, cavitation, lower filtration capacity and blocks valves.

Bearing wear due to water contamination

Hot Plate Test - Semi-quantitative FTIR (infrared) - Qualitative Spectroscopy – Indicative Karl Fischer – Coulometric titration -

Quantitative Distillation, ASTM D95 - Quantitative

Water Detection Methods

The hot plate test is very effective in detecting water in quantities equal to or higher than 0.1% (1000 ppm or more).

Results: 0.0%, 0.1%, 1.0%, 2.0%, 5%

Hot Plate Detection Method

0.0%, 0.1% 1.0% 2.0%

FTIR Detection Method

Water & glycol

Degradation Products (nitrate-sulfate)

Oil Thickening

New Oil

3.5

3.0

2.5

2.0

1.5

1.0

0.5

4000 3500 3000 2500 2000 1500 1000

Wavelength (cm-1)

Ab

sorb

ance

Oxidation

Spectroscopy

Presence of boron, B

Presence of sodium, Na

Presence of potassium, K

Distillation MethodCooler

Water

Heating plate

Quantitative Method for High Concentration (5% -100%)

Applicable when and where water contamination level is critical and must be kept very low.

Both equipment and oil can accept a certain amount of water

Result is given in percent (ex: 0.1% = 1000 ppm).

KF - Karl Fisher ASTM D4928

Antifreeze

Glycol and water are the main constituents (50/50) of antifreeze or coolant liquids.

Ethylene Glycol (High heath transfer)

Propylene Glycol (More toxic, less popular)

Additives: Phosphates, borates, molybdates, silicates, nitrates, potassium ...etc

Glycol Contamination

Effects of Glycol

Oil thickening, change in viscosity Emulsion and gels, dispersion Acid formation Precipitation of additives Lower oil debit Filter degradation Bad lubrification

Glycol Detection Methods

FTIR DetectionDegradation Products

(nitrate-sulfate)

Oil Thickening

New Oil oxydation

3.5

3.0

2.5

2.0

1.5

1.0

0.5

4000 3500 3000 2500 2000 1500 1000

Wave length (cm-1)

Abs

orba

nce

Water & glycol

Detection by Spectroscopy

Presence of Boron, B

Presence of sodium, Na

Presence of potassium, K

Presence of silicium, Si

Detection by ASTM D2982 Method Colorimetric method

A HCL solution is added to oil to oxidize glycol

The reaction produces aldehyde

Aldehyde reacts alternatively with a reactant, producing a positive color change from colorless to pink / to purple

The darker the color, the more glycol there is

Results: 0.01%, 0.05% and 1 %

Detection by GC ASTM D4291 Method

This method is the most precise, although more expensive and more time consuming than others.

The most widely used GC procedure is ASTM 4291.

First you must extract glycol

Extract is then injected into the GC where polar components are separated and detected on a chromatogram.

1. Fuel Dilution ASTM D3828

2. FTIR Detection

3. Detection by Flash Point

4. GC, ASTM D Detection is the most precise and most expensive method.

5. The most currently used GC method is ASTM 3524

Fuel ContaminationFU - percent of unburned diesel or gasoline

present in engine

FP - Temperature at which the lubricant flashes when exposed to an open flame

FIRE - Temperature at which the lubricant continues to burn when exposed to an open flame

FP – Flash Point ASTM D92 FIRE – Fire Point ASTM D92

CLP - Temperature at which crystals of paraffin wax precipitate from solution to obstruct filtration systems.

PP - Temperature at which the fuel or oil is not moving (immobilized) once at an angle of 90 degrees to a horizontal surface.

CLP – Cloud Point ASTM D97 PP – Pour Point ASTM D97

Recommended on all pieces of equipment requiring filtration

Cleanliness level expressed in ISO 4406 (1999) or NAS 1638 codes

Dimensions () and quantity of the particles Water particles are also counted Evaporation may be used to eliminate part of this

water for a better particle counting.

PC – Particle Counting

17/14/13 4

6

14

ISO 4406:1999

Particles by ml

More than Up to Scale

160,000 320,000 25

80,000 160,000 24

40,000 80,000 23

20,000 40,000 22

10,000 20,000 21

5,000 10,000 20

2,500 5,000 19

1,300 2,500 18

640 1,300 17

320 640 16

160 320 15

80 160 14

40 80 13

20 40 12

10 20 11

5 10 10

2.5 5 9

1.3 2.5 8

0.64 1.3 7

ISO 4406 NAS 1638

23/21/18 12

22/20/18 --

22/20/17 11

22/20/16 --

21/19/16 10

20/18/15 9

19/17/14 8

18/16/13 7

17/15/12 6

16/14/12 --

16/14/11 5

15/13/10 4

14/12/9 3

13/11/8 2

12/10/8 --

12/10/7 1

12/10/6 --

Comparison between ISO 4406 & NAS 1638 Cleanliness codes

DR – Direct Reading

Recommended for gearboxes, differentials and screw compressors

Detects metallic, non–metallic particles, contaminants included

Indicates changes in wear rate and severity

Quantitative Ferrography

AF – Analytical Ferrography In-depth DR

Type of wear

Detection of large particles

Degradation products by

oxidation in suspension

Recommended systematically

when particles are detected

Wear Particles - Debris

By abrasion Copper Alloy Slicing

Red OxidesBlack Oxides

Particle Quantifier, PQ

Sensitive Magnetometer - measures the mass of ferrous debris in the sample – in PQ index.

The PQ index test is quantitative

Recommended for motor oils

When iron is high and PQ is low ~> small particles

When iron and PQ are high ~> small particles

When PQ is high and iron is low ~> large particles

Interpretation of PQ results

Analex PQA

Questions

Oxidation

Thermal Degradation

Factors: air, heath, water; contamination, radiation, additive degradation, etc.

Varnish

Varnish is a thin, oil-insoluble layer of oil-degradation residues and by-products that develops over time on the internal surfaces of lubricated equipment. This can even occur on well-maintained machines with clean lubricants.

Causes

How do we Measure Varnish?

Varnish formation potential is measured by : quantitative spectrophotometric analysis (QSA)

Contaminant, sub-product evaluation method based on the extraction by disssolution of insoluble contaminants, through amembrane, measured in CIE_dE, on a scale of 1 to 100.

The higher CIE_dE is, the higher the proportion of varnish in the oil.

Varnish Results

MONITOR MARGINAL CRITICALNORMAL

CIE_dE Results on a 1 – 100 scale

< 15 15 ~ 30 30 ~ 40 > 40

Photo of membrane

PT – Filter Analysis

Used in the aviation industry

Indicates the type of wear particles

Dissolution and filtration of magnetic particles

Action!!

Change oil if viscosity is 20% of initial value

Change oil if fuel has been detected and low viscosity

Change oil if glycol has been detected

Action !! Filter oil if code is higher than recommended

Inspect machine if wear is severe

Proceed to AF test if volume of large particles is high

Eliminate the source of water infiltration

Monitor color and odor of oil, oxidation index

Eliminate varnish if detected

Test Packages

ENGINES

TESTS COMPLÉMENTAIRES CODE DESCRIPTION MÉTHODEQUANTITÉ D’HUILE

REQUISE CALENDRIER         

  SP  ANALYSE SPECTROMÉTRIQUE ICP ASTM D5185      FTIR  ANALYSE INFRAROUGE... FOURIER JOAP    

MOBFTV VIS100  VISCOSITÉ À 100 ◦C  ASTM D445 100ml MENSUEL  FU  DILUTION DU CARBURANT ASTM D3828      HP  TEST DE CRÉPITEMENT PMC      COPOF  COULEUR,ODEUR,CLARTÉ,PRÉCIPITÉ,MOUSSE PMC    

           SP  ANALYSE SPECTROMÉTRIQUE ICP ASTM D5185      FTIR  ANALYSE INFRAROUGE... FOURIER JOAP    

  VIS100  VISCOSITÉ À 100 ◦C  ASTM D445    MOBPLUS TBN  INDICE D'ALCALINITÉ ASTM D4739 100ml MENSUEL

  FU  DILUTION DU CARBURANT ASTM D3828      HP  TEST DE CRÉPITEMENT PMC      COPOF  COULEUR,ODEUR,CLARTÉ,PRÉCIPITÉ,MOUSSE PMC    

  SP  ANALYSE SPECTROMÉTRIQUE ICP ASTM D5185     FTIR  ANALYSE INFRAROUGE... FOURIER JOAP     VIS40  VISCOSITÉ À 40 ◦C  ASTM D445     VIS100  VISCOSITÉ À 100 ◦C  ASTM D445    

MENGP VI  INDICE DE VISCOSITÉ (VIS40+VIS100)  ASTM D2270 100ml MENSUEL

GCFCHROMATOGRAPHIE EN PHASE GAZEUSE CARBURANT ASTM D3524, ASTM D3525    

PQ  INDICE DE QUANTIFICATION DES PARTICULES PMC     HP  TEST DE CRÉPITEMENT PMC      COPOF  COULEUR,ODEUR,CLARTÉ,PRÉCIPITÉ,MOUSSE PMC    

HYDRAULIQUEPompes hydrauliques, Valves hydrauliques, Actionneurs hydrauliques

CODE DES TESTS COMBINÉS CODE DESCRIPTION MÉTHODE

QUANTITÉ D’HUILE REQUISE CALENDAR

SP  ANALYSE SPECTROMÉTRIQUE ICP ASTM D5185    

FTIR  ANALYSE INFRAROUGE … FOURIER JOAP    

PRAN VIS40  VISCOSITÉ À 40 ◦C   ASTM D445 100ml MENSUEL

  PC  COMPTAGE DE PARTICULES ISO 4406    

COPOF  COULEUR,ODEUR,CLARTÉ,PRÉCIPITÉ, MOUSSE   PMC    

       

SP  ANALYSE SPECTROMÉTRIQUE ICP ASTM D5185    

FTIR  ANALYSE INFRAROUGE … FOURIER JOAP    

VIS40  VISCOSITÉ À 40 ◦C   ASTM D445    

PRANP PC  COMPTAGE DE PARTICULES ISO 4406 100ml MENSUEL

TAN  INDICE D’ACIDITÉ ASTM D974,ASTM D664    

KF  TITRATION D’EAU DE KARL FISCHER ASTM D4928    

COPOF  COULEUR,ODEUR,CLARTÉ,PRÉCIPITÉ, MOUSSE  PMC    

BOÎTE À ENGRENAGE, DIFFERENTIEL & COMPRESSEUR

CODE des TESTS COMBINÉS CODE DESCRIPTION MÉTHODE

QUANTITÉ D’HUILE REQUISE CALENDRIER

  SP  ANALYSE SPECTROMÉTRIQUE ICP ASTM D5185     FTIR  ANALYSE INFRAROUGE… FOURIER JOAP    

DROT VIS40  VISCOSITÉ À 40 ◦C   ASTM D445 100ml MENSUEL DR  LECTURE DIRECTE PMC      COPOF  COULEUR,ODEUR,CLARTÉ,PRECIPITÉ,MOUSSE  PMC               SP  ANALYSE SPECTROMÉTRIQUE ICP ASTM D5185      FTIR  ANALYSE INFRAROUGE… FOURIER JOAP      VIS40  VISCOSITÉ À 40 ◦C   ASTM D445    

DROTP DR  LECTURE DIRECTE PMC 100ml MENSUEL  KF  TITRATION D’EAU DE KARL FISCHER ASTM D4928      TAN  INDICE D’ACIDITÉ ASTM D974,ASTM D664      COPOF  COULEUR,ODEUR,CLARTÉ,PRECIPITÉ,MOUSSE  PMC    

GRAISSERoulements, Compresseurs, Différentiel,

Boîte à engrenages, Transmission, Turbine

CODE des TESTS COMBINÉS CODE DESCRIPTION MÉTHODE

QUANTITÉ D’HUILE REQUISE CALENDRIER

GRS SP    ANALYSE SPECTROMÉTRIQUE PMC  2g  MENSUEL 

GRSPQ GRS   ANALYSE SPECTROMÉTRIQUE ICP PMC 10g MENSUEL

PQ   INDICE DE QUANTIFICATION DES PARTICULES PMC    

VERNISCompresseurs, Boîtes à engrenages, Hydraulique, Turbines

CODE des TESTS COMBINÉS CODE DESCRIPTION MÉTHODE

QUANTITÉ D’HUILE REQUISE CALENDRIER

  QSA   ANALYSE SPECTROPHOTOMÉTRIQUE QUANTITATIVE PMC    

VBT GAF    ANALYSE GRAVIMÉTRIQUE (FILTRATION) PMC 200 ml TRIMESTRIEL 

COPOF    COULEUR,ODEUR,CLARTÉ,PRÉCIPITÉ,MOUSSE PMC    

       

Aviation

Spectrometric  wear metal check (ASTM 5185) Viscosity , ASTM D 445 Acidity (TAN) Water content (KF) Particle count, (NAS 1638 / ISO4406)

Aviation Hydraulic Fluid

Patch test (PT) Chip test when recommended

Metal filter analysis

Test Reports

Sample Report

Sample Report

Sample Report

Sample Report

Sample Report

Sample Report

QUESTIONS