introduction to oil analysis

8/2/2019 Introduction to Oil Analysis

1/29

Click to edit Master subtitle style

3/29/12

Brief introduction to oilanalysis


2/29


3/29/12

By the end of thispresentation you will beable toRead ISO cleanness code for the oilKnow about the oil types

Familiar with some chemical properties of theoil

Familiar with contamination type of the oil

Familiar with sample point do and do not


3/29

3/29/12

Predictive

maintenance (PdM

)Predictive maintenance techniques help determines thecondition of equipment in order to predict whenmaintenance should be performed. This approach

Offers cost savings over routine or time-based becausetasks are performed only when warranted.

The main value of Predicted Maintenance is to allowscheduling of corrective maintenance

Prevent unexpected equipment failures. The key is "theright information in the right time".

By knowing which equipment that needs maintenance, themaintenance work can be better planned (spare parts,

people )and what would had been "unplanned stops" aretransformed to shorter and less "planned stops" thusincreasing plant availability.

increased plant safety, less accidents with negative impacton environment,

optimized spare parts handling


4/29


3/29/12

Technologies applied inPdm

vibration and sound measurement analysisthermal imageoil analysismotor current signaturealso ultra sonic and non destructive test


5/29

3/29/12

MaintenanceIdentify and measure lube

contamination and component wear

Eliminate unnecessary overhauls orinspections

Reduce in service failures and fieldrepairs

Establish proper lubricant serviceintervals

Management

Improve cost assessment and control

for equipment, labor and materials


6/29

3/29/12

What we need from

our oilPrevent wear(anti wear additives)

Reduce friction and coolant for surface

Be stable wide temperature rangetemperatures

Maintain viscosity throughout serviceinterval

To keep internal components cleanTo prevent rust(rust inhibitor)

To maintain high levels of effectivenessthroughout service life


7/29

3/29/12

Oil classification

typesMineral oils

Manufactured from crude oil containingmany impurities; it has to be distilled toseparate it into Gases, fuel liquids,lubricant fractions and heaviercomponents such as asphalt Further

processing of the lubricant removesadditional impurities

Synthetic oils


8/29

3/29/12

As a rule of thumb Oilconsider to becontaminated whenchemical properties are

changed from OEMstandard or the base linemeasurements


9/29


10/29

3/29/12

DIELECTRIC

STRENGTHThis test measures an oil's ability to

withstand an electric current withoutfailing. Oil is placed in the gap between

two electrodes and an increasinglyhigher voltage is applied to the oil untilan arc forms across the gap

In large transformers, the circulating oil

is formulated to act as an insulator. Therelative insulating capacity of thetransformer oil is indicated by thedielectric strength. Generally, small

amounts of water, dirt, or metal will


11/29

3/29/12

FERROGRAPHY

Ferrography is an analytical technique inwhich wear metals and contaminant

particles are magnetically separated

from a lubricant and arranged accordingto size and composition for furtherexamination. It is widely used in oilanalysis to

determine component condition throughdirect examination of wear metal

particles.


12/29

3/29/12

Total Acid Number

(TAN)Measures the total amount of acidic

material present in the lubricant.Generally, an increase in TAN above that

of the new product indicates oiloxidation or contamination with an acidic

product

units

milligrams of potassium-hydroxide pergram of sample, or mg/Gm or mg/KOH gr

New fresh oil will start around 0 2


13/29

3/29/12

Oil sample analysis

grouped in three maincategories

1. Wear metals

2. Contaminants

3. Additives


14/29

3/29/12

Wear metalsAdhesive wearExcessive load, low speed and/or reductions in fluidviscosity can reduce the oil film thickness to a pointwhere metal-to-metal contact occurs. Surface

asperates are "cold welded" together and particlesare sheared off as surfaces move.


15/29

3/29/12

Wear metals

Abrasive wearAbrasive wear occurs when a harder material is rubbing

against a softer material.Abrasive wear is a primary wear mechanism. Particles enter

the clearance space between two moving surfaces, and actlike cutting tools to remove material from the surfaces. The

particle sizes causing the most damage are those equal to

and slightlylarger than the clearance space


16/29

3/29/12

Wear metals

Fatigue wear

Fatigue wear of a material is caused by a cyclingloading during friction, spalling, and pitting of the

component part Surfaces.


17/29

3/29/12

Wear is controlled withantiwear additives, whichcoat the lubricated surfaces

and reduce direct part to

part contact.


18/29

3/29/12

Contaminants

Depending upon the circumstances,many different substances may beclassified as contaminants. Silicon, in the

form ofSilicon dioxide (sand) is one of the most

common contaminants

What about other types ofcontamination?

As destructive as particulatecontamination can be, there are othercontaminants that also contribute to oildegradation and premature machine


19/29

3/29/12

effect of watercontamination

Water alone is a significant factor inlubricant degradation. When combinedwith iron or copper particles, water

becomes even more powerful inattacking lubricant base-stocks andadditives. The adverse effects of waterin oil include:

Lubricant breakdown, through oxidationand additive break down.

Changes in viscosity, affecting the abilityof a lubricant to maintain the film

thickness necessary to protect the


20/29

3/29/12

Example show watercontent level andbearing life


21/29

3/29/12

As a rule of thumbwater concentrationshould not exceed

300 PPM.


22/29

3/29/12

Other CONTAMINENT

sourceSOURCES

1-Aluminium

Pistons, bearings2- Copper

Bearings, bushings, washers etc.

3- Iron

Piston rings, ball and roller bearings


23/29

3/29/12

3. Additives

Additives are chemical compoundsadded to oils, fuels, and coolants toimpart specific beneficial properties

Additives create new fluid properties,enhance properties already present andreduce the rate at which undesirablechanges take place in a fluid during

serviceundesirable changes take place in a fluid

during service.

MOLYBDENUM


24/29

3/29/12

How is oil cleanliness

quantified?ISO 4406 establishes the relationship

between particle counts andcleanliness ,This international standard

uses a code system to quantifycontaminant levels by particle size inmicrometers (m). Using ISO 4406, amachine owner/operator can set simple

limits for excessive contamination levels,based on quantifiable cleanlinessmeasurements.


25/29

3/29/12

ISO 4406


26/29

3/29/12

EXAMPLE

ISO 4406 Rating -- 16/13/11

16 = range of number of particles >4




27/29

3/29/12

How clean does your oil

need toMachine/element

ISO Target

Roller bearing16/14/12

Journal bearing17/15/12

Industrial gearbox

17/15/12

Determine the proper sampling


28/29

3/29/12

Determine the proper samplingpoint and method do and do

not.

Do

Sample from live fluid zones Turbulentzones such as Elbows if applicable

Downstream of system(Bearings, gears)if applicable

Sample while machine isRunning

Sample under typical working conditions

Do not

Dead legs

Laminar flows


29/29

3/29/12

Sample report

1

introduction to oil analysis

Documents