Wear metal analysis

MAINLUBE SUPERIOR MAINTENANCE LUBRICANTS PTY. LTD.

14 Underwood Avenue, Botany NSW 2019, Sydney, Australia

Ph +61-2-9700-0880, Fax +61-2-9700-0881

Wear Particle Analysis

The Wear particle Analysis is a Pro-active Predictive

Maintenance System.

Wear Metals Particles are extracted from an oil sample

then magnified up to a 1000X for

wear mode identification.

Wear mode identification is possible when viewing;

> What the particles are, > The particle’s size, > How the metal particle was removed, > Temperature of removal.

The above information can determine the machine’s past, and therefore future Wear Mode.

Pro-Active Maintenance uses the Wear Mode

information to correct and prevent future reocurrence. © Mainlube Superior Maintenance Lubricants Pty Ltd of 17

Wear Modes in Machinery

Normal Rubbing Wear is when the machine’s normal operation lightly defoliates

the wear surface.

Normal Rubbing Wear Particles depending on the machine, are 0-10 microns

sized platelets. In a gearbox situation Normal Rubbing Wear could register

0-60 ppm of wear metals using Atomic Absorption Spectrometer.

This is a visual example of Normal Rubbing Wear Particles

@ 600X Sized 5-10 microns.

The images below are from machines that appear to be in an

“exaggerated” Normal Rubbing Wear Mode. If the wear mode is building,

then it’s not normal. (Scuffing Wear)

They are the end result of other larger wear modes being milled down as

they are forced through the load zone by the lubricant flow. They appear,

as a heavy concentration of Normal Rubbing Wear Particles.

© Mainlube Superior Maintenance Lubricants Pty Ltd of 17

Three Body Contact is the cause of most damage.

Below shows the normal “Lubricating Film Thickness” in each application in operating conditions.

Particles larger than the “lubrication film thickness” become Three Body Contact Contaminate Particles

as the lubricant flow forces them through the load zone, easily penetrating the lubricating film,

continually damaging load bearing surfaces

Roller Bearings 0.4 to 1 Micron

Ball Bearings 0.4 to 0.7 Micron

Journal Bearings 0.5 to 25 Microns

Hydrostatic Bearings 5 to 100 Microns

Gears 0.1 to 1 Micron

Dynamic Seal 0.05 to 0.5 Micron

Gear Pump, Tooth to side plate 0.5 to 5 Microns

Gear Pump, Tooth tip to case 0.5 to 5 Microns

Vane Pump, Sides 5 to 13 Microns

Vane Pump, tip 0.5 to 1 Micron

Piston Pump, piston to bore 5 to 40 Microns

Piston Pump, Valve plate to cylinder 0.5 to 5 Microns

Servo Valves, Orifice 130 to 450 Microns

Servo Valves, Flapper Wall 18 to 63 Microns

Servo Valves, Spool to Sleeve 1 to 4 Microns

Actuators 130 to 450 Microns

Human Hair 70 to 100 Microns


3 body Fatigue, Spheres, Laminar, Dark Metallo and Black Oxide Wear Metal Particles are made possible by Fluid Contamination.

Abrasion Three-body sliding contact ploughs and cuts away material from component surface, leading to loss of load bearing surface, misalignment and leakage. Fatigue Three-body rolling contact roughens and microdents surfaces, fracturing load bearing surfaces. Erosion Particles suspended in high velocity fluid impact against surface, cutting and wearing away load bearing surfaces. Striction Particles lodged between machine components during the down periods cause slip stick and jamming when machines restarted. Fouling Of nozzles, flow passages, oil galleries, feed lines, heat exchangers. Corrosion Attack by water or aggressive chemicals such as organic Acids formed during oxidation of fluids. Fluid Breakdown Involves diverse mechanisms such as contaminate catalysed reactions, precipitation of additives by foreign chemicals or water, and depleting anti-wear additives by particle induced wear. © Mainlube Superior Maintenance Lubricants Pty Ltd of 17

Spherical Particles sized 4-5 microns are generated in 2 and 3 Body

Fatigue cracks on rolling bearing wear surfaces.

As the lubricant flow forces wear metals through rolling bearing tracks, 2 and 3

Body Fatigue cracks trap the wear metal debris, the rotation rolls the debris over

and, building the Sphere until it is large enough to escape. Research has shown,

as the bearing is failing, one to two million spheres will be released, pre-warning

an up and coming bearing failure. Other Spheres are generated in gears,

these Spheres are usually 10 microns or larger. The images below show

Spherical Wear Metal Particles from gears and bearings.


Sliding Wear occurs when the lubricants film strength has been insufficient in

providing separation between two wear surfaces, allowing metal to metal contact.

It’s like the glacier sliding down the hill, it bulldozers along the surface

tearing everything off in it’s path. Severe sliding wear generates extreme heat,

in some cases over 1000°C in the load zone. How many times you have seen

a large gearbox showing gear case temperatures above 100°C?

How much energy would it take to heat the gearbox to this temperature?

How much energy is being wasted by tearing off metal, which could be

turned into production?

To generate this heat, the machine is tearing off of 50 to 200 micron

chunks of metal and releasing them into the lubricant flow. This forces

the metal chunks through the rolling elements of the machine causing

secondary wear. Gear faces subject to high temperatures over time,

anneal the gear tooth surfaces, softening them promoting further wear.

Here are examples of Sliding Wear Particles 500X-600X Sized 40-200 Microns.


Cutting Wear Particles are caused by hard contamination, usually

Silica (Sand), or other hard contaminants, or an acute angle of

metal to metal contact that has occurred between the machine’s components.

The distinctive curled swarf, shapes of Cutting Wear Particles, show a hard

contaminate has penetrated the lubricating film, gouging out the metal.

Cutting Wear is an abnormal wear mode. Cutting Wear Particles results

in machinery damage and should corrected as soon as possible.

Filtergram Analysis identifies all wear mode types present, then recommends

changes and monitors the immediate effect of the changes to ensure success.


2 Body Fatigue Wear chunks occur when the machines cyclic application

of the stress, is in excess of the design value.

The machine has been overloaded, past the capabilities of the metals surface,

slightly collapsing the metals sub-surface creating a crack or dent.

Repetitive bruising in this area further fractures the metals sub-surface causing

the area to eventually spall out. This creates the familiar deep pitting and scaring

damage observed on load bearing surfaces. Spheres are usually generated in

these areas.

2 Body Fatigue Wear Particles are flat platelets with a major dimension to

thickness ratio of approximately 10:1, a smooth surface and a random

irregularly shaped circumference.

These spalling metal particles are carried by the oil flow through other load

zones, snowballing the effect and further damaging load-bearing surfaces.

Damage will continue to this machine until the contamination is completely

removed




3 Body Fatigue Wear Chunks are wear metal Particles that began when

a foreign body was forced through the load zone creating a micro crack or dent.

Repetitive bruising in this area fractures the metals surface, causing the area to

eventually spall out. This creates the familiar loss of hardened surface, scaring

and light pitting damage observed on load bearing surfaces.

These spalling metal particles are carried by the oil flow through other load

zones, snowballing the effect and further damaging load-bearing surfaces.


removed.


changes and monitors the immediate effect of the changes to ensure success. If

not corrected this wear mode will escalate in Scuffing Wear and eventual failure.

Three Body Wear

Scuffing Wear

© Mainlube Superior Maintenance Lubricants of 17

Scuffing Wear Typical of “Running In” mode.

New machinery must be “run in” to allow load-carrying surfaces to “bed in”.

When the components of a machine are new, especially after an overhaul,

bearings and gears can be sourced from may different places. There are hills

and valleys present that must be smoothed out to achieve the correct “light

defoliation” of the wear surface to settle the machine down into Normal Rubbing

Wear mode.

After a machine has “bedded in” the machine must be flushed and refilled with

fresh lubricant. If left, scuffing wear will be carried by the oil flow through other

load zones, snowballing the effect generating 3 Body Fatigue Wear, then on to

Laminar Wear and further damaging the new load bearing surfaces.


removed.

Filtergram Analysis identifies all wear mode types present then recommends


The images below are from a large reduction box that has been freshly

overhauled and run for 100 hours and benchmarked.


Red Iron Oxide Particles are easily formed when water is present in the

system, or has been in the system in the past.

If heavy amounts of large Red Iron Oxide Particles are found in the sample, this

will indicate the presents of water in the system.

Red Iron Oxide particles vary in colour and size with the amount of water present.

The presence of other minerals, in the water and the size of the crystals, all have

an effect on the way the Red Oxide Particles form. Below are several different

forms of Red Iron Oxide Particles, the effect of the formation of these particles

on the metal surfaces causes severe surface corrosion damage and subsequent

loss of load carrying surface area, this is catalysed by the formation of the Red

Iron Oxide Particles.




Dark Metallo & Black Oxide Particles are formed when machine is being over

driven beyond the capability of the lubricant. The heat and pressure generated

causes lubricant starvation. When Red Iron Oxide (rust), is forced through the

load zone it polymerises and forms Dark Metallo-Oxide and Black Oxide

Particles. Water is not present when Black Oxide Particles and Dark Metallo-

Oxides are formed. There are many forms of Iron Oxides FeO, Fe2O3 and

Fe3O4.

To rectify this wear mode the lubricant should be up graded to a product more

suitable to the machines operating environment. It is not unusual to see particles

oxidised to varying degrees of colour , from straw through to blue purple.




Laminar Wear is a secondary wear mode, which is the end result of all wear

modes being forced through the load zone by the lubricant flow. Their passage

damages load bearing surfaces, forming large “rolled out” particles that contain

all wear modes created earlier. The machine’s rolling elements roll the abnormal

Wear Metal Particles flat, to the distinctive length to thickness 30:1 ratio.

Typical operating lubrication film clearance in Industrial Ball Bearing, Roller

Bearing and Meshing Gear Sets are of 0.1 to 1-Micron clearance. When spalls or

breakages occur, or foreign contaminates are introduced to the lubrication

system, the foreign particles could be 100’s of microns in size, the human hair is

60 to 100 microns in diameter. The lubricant flow forces these huge foreign

particles, through the machine’s rolling gears and bearings causing extensive

damage to the machines running surfaces.

As these chunks of metal, up to 500 microns in size, are forced through the

bearings and gears, with a maximum clearance of 1 micron, they crush and mill

down forming the 0 to 15 microns sized abnormal wear metals that register when

an Atomic Absorption Spectrometer test is preformed. Most people have

trended the wear rate using the Atomic Absorption Spectrometer from the

local Caterpillar Agent or Fuel Company. The problem with this type of

analysis is wear particles are required to be milled down by the

machine’s rolling elements to the small size of 0-10 microns before they

register in the test. Particles bigger than 10-micron increase the particle

count but cannot be identified. This means this the Atomic Absorption

Spectrometer often only registers the introduction of a contaminant 2 to 3

months after the event. Undetected contaminates cause extensive damage to

the machine’s wear surfaces, shortening their life by cracking and denting the

surface in the end forming other abnormal wear metals shown ahead. Filtergram

Analysis identifies all wear mode types present, then recommends changes and

monitors the immediate effect of the changes to ensure success.

Damage will continue to the machine until the contamination is completely

removed. © Mainlube Superior Maintenance Lubricants Pty Ltd of 17

Here are examples of Laminar Wear Particles 500X-600X Sized 40-200

Microns.

Note: See how as the time extends the particles are broken up smaller.


ISO SOLID CONTAMINANT CODE ISO 4406

Range Number Chart

Range Number 24 indicates 80,000 to 160,000 particles per ml of oil Range Number 23 indicates 40,000 to 80,000 particles per ml of oil Range Number 22 indicates 20,000 to 40,000 particles per ml of oil Range Number 21 indicates 10,000 to 20,000 particles per ml of oil Range Number 20 indicates 5,000 to 10,000 particles per ml of oil Range Number 19 indicates 2,500 to 5,000 particles per ml of oil Range Number 18 indicates 1,300 to 2,500 particles per ml of oil Range Number 17 indicates 640 to1,300 particles per ml of oil Range Number 16 indicates 320 to 640 particles per ml of oil Range Number 15 indicates 160 to 320 particles per ml of oil Range Number 14 indicates 80 to 160 particles per ml of oil Range Number 13 indicates 40 to 80 particles per ml of oil Range Number 12 indicates 20 to 40 particles per ml of oil Range Number 11 indicates 10 to 20 particles per ml of oil Range Number 10 indicates 5 to 10 particles per ml of oil Range Number 9 indicates 2.5 to 5 particles per ml of oil Range Number 8 indicates 1.3 to 2.5 particles per ml of oil Range Number 7 indicates 0.64 to 1.3 particles per ml of oil Range Number 6 indicates 0.32 to 0.64 particles per ml of oil Range Number 5 indicates 0.16 to 0.32 particles per ml of oil Range Number 4 indicates 0.08 to 0.16 particles per ml of oil Range Number 3 indicates 0.04 to 0.08 particles per ml of oil Range Number 2 indicates 0.02 to 0.04 particles per ml of oil Range Number 1 indicates 0.01 to 0.02 particles per ml of oil


ISO SOLID CONTAMINANT CODE ISO 4406

The ISO Solid Contaminant Code ISO 4406 is the single most wide spread system for representing contaminant

levels in Hydraulic or Lube Oil Systems.

ISO 4406 uses 2 range numbers, the first one representing particle counts above 5 microns and the second one

represent particles counts above 15 microns.

The first range number is separated for the second range number by a slash, (eg 15/12) From the chart, the particle

count ranges correspond to each adjacent range.

A typical ISO Code for a hydraulic system is ISO 16/13.

By checking the Range Chart we can see that

Range Number 16 means there are between 320 and 640 particles per ml of oil bigger than 5 microns.

And

Range Number 13 means there are between 40 and 80 particles per ml of oil bigger than 15 microns included in this

first total of between 320 and 640 particles per ml of oil.

This equates to approximately I milligram of dirt per litre of fluid or 1 ppm.

A Vickers Chart of Recommended Cleanliness Codes uses the Pal or Vickers System, same as this ISO 4406

System’s Range Numbers. Vickers being a leading Hydraulic Equipment Manufacturer developed this system to

prevent unnecessary wear in hydraulic systems.

The difference between the Vickers System and ISO 4406 is that Vickers also consider particles 2 microns and

greater, this range is recorded by adding another set of numbers in front for the number of particles greater than 2

microns. eg 18/15/12, or;

(1300 to 2500 particles >2 microns/ 160 to 320 particles >5 microns/ 20 to 40 particles >15 microns).

At all times the first Range Number will indicate the total number of particles of all sizes per ml of lubricant, the

subsequent Range Numbers indicate the sizing of the particles in this first total

Both systems without the previous page’s chart offer limited information until the system has been learnt and

understood. Once this is accomplished the user will notice any unusual Range Number changes and be very accurate

with early detection and correction of abnormal wear modes.


Mainlube Lubricant’s Analysis Requesting Sheet

Maintenance Lubricants Pty Ltd, PO Box 353, Botany NSW 1455 14 Underwood Avenue, Botany NSW 2019 Ph.02-9700-0880, Fax 9700-0881, E-mail: [email protected]

Today’s Date: ___/___/___ Sample Received: ___/___/___Lab Sent: ___/___/___ Test Results: ___/___/___

NOTE: TO ENSURE PROCESSING OF THIS SAMPLE ALL APPLICATION DETAILS MUST BE COMPLETED

CUSTOMER NAME, ADDRESS, PH & FAX. _________________________________________________________________________________________________ _________________________________________________________________________________________________ _________________________________________________________________________________________________ Attention : Phone : Fax :

NOTE: TO ENSURE PROCESSING OF THIS SAMPLE ALL APPLICATION DETAILS MUST BE COMPLETED APPLICATION DETAILS

Unit, Vehicle, Plant, Rego, Id, Number, Name, etc:______________________________________ Equipment Make :_________________________ Equipment Model:____________________ Total Machine Hours/Kms:_____________ Hours/Kms on Oil:______________

Lubricant Brand, Machine Location :___________________________ Type, & SAE :___________________________________________

Filter Changed: Yes / No. Fuel Type: Diesel/Petrol/Electric/Gas Other ___________________ Top Up Ltrs : ______________. Oil Changed: Yes / No. OIL QUANTITY _________Litres HP/kW _______________

Sample Taken From: θ Engine; θ Hydraulics; θ Reduction Gearbox; Type:_____________ θ Manual Transmission; θ Auto Transmission;

θ Front Axle; θ Rear Axle; θ Final Drive which? __________;θ Turbine; θ Bearing Housing & Type__________________

θ Air Compressor; θ Refrigeration Compressor; θ Vacuum Pump; θ Heat Transfer System; Other ___________________ Metal Types expected in sample eg: Steel, Bronze etc:___________________________________________________________________________; How & Where Was Sample Taken: ___________________________________________________________________________________ Any Recent repairsrepairs:___________________________________________________________________________ _________________________________________________________________________________________________

Please continue on back of form with further relevant observations on, Lubricant smell, visual appearance, type of environment, temperature etc, Information Important to Oil Test:

θ θ Person Completing/Requesting Test,

Print Name: ___________________________Signed: ________________________Date: ____/____/____

TEST TYPES REQUIRED:

Wear Particle Analysis @ $85 per each normal to $140 on complex samples. Predicts future wear & machine life, checks machine’s condition often providing several months warning of component failure allowing planned downtime. Wear Metal PPM Analysis @ $70 Per Sample. Used for evaluating past machine wear, provides PPM Wear Metals Sized 0-5 Microns, Particle Count, Water, Fuel, Soot, Oxidation. Lubricant Condition Analysis @ $70 Per Sample. Used for establishing lubricant condition, whether lubricant should be changed and project remaining lubricant life. Please Note: Urgent Rush Wear Particle Analysis can be completed @ plus 100% rate, turn around approx 2 hours from receipt.

Please do not completely fill the sample bottle as this can prevent correct agitation and subsequent testing. Please fill the Mainlube sample bottle to between the 2nd and 3rd rings, about ¾ full. For Wear Metal PPM Analysis also fill the Red Cap with the same unused clean new oil as the sample. Affix the white Cap and fill out this sheet correctly and send with sample to the above address. Photocopy this sheet and fill out to send with your sample and keep for your records.


Test No.

Wear metal analysis

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