HANDBOOK FILTRATION PARKER

40
The Handbook of Hydraulic Filtration

Transcript of HANDBOOK FILTRATION PARKER

Page 1: HANDBOOK FILTRATION PARKER

The Handbook ofHydraulic Filtration

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The Handbook of Hydraulic

Filtration is intended to

familiarize the user with all

aspects of hydraulic and

lubrication filtration from

the basics to advanced

technology.

It is dedicated as a reference

source with the intent of

clearly and completely

presenting the subject matter

to the user, regardless of the

individual level of expertise.

The selection and proper use

of filtration devices is an

important tool in the battle to

increase production while

reducing manufacturing costs.

This Handbook will help the

user make informed decisions

about hydraulic filtration.

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Contamination Basics 2

Contamination Types and Sources 4

Fluid Cleanliness Standards 12

Filter Media Types and Ratings 16

Filter Media Selection 20

Filter Element Life 22

Filter Housing Selection 24

Types and Locations of Filters 28

Fluid Analysis 32

Appendix 34

Table of Contents

1

PAGESECTION

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Contamination Causes Most Hydraulic Failures

The experience of designers and usersof hydraulic and lube oil systems hasverified the following fact: over 75% ofall system failures are a direct result of contamination!

The cost due to contamination is staggering, resulting from:▼ Loss of production (downtime)

▼ Component replacement costs

▼ Frequent fluid replacement

▼ Costly disposal

▼ Increased overall maintenance costs

▼ Increased scrap rate

Functions of HydraulicFluid

Contamination interferes with the fourfunctions of hydraulic fluids:1. To act as an energy transmission

medium.

2. To lubricate internal moving parts ofcomponents.

3. To act as a heat transfer medium.

4. To seal clearances between movingparts.

If any one of these functions isimpaired, the hydraulic system will notperform as designed. The resultingdowntime can easily cost a large manu-facturing plant thousands of dollarsper hour. Hydraulic fluid maintenancehelps prevent or reduce unplanneddowntime. This is accomplishedthrough a continuous improvementprogram that minimizes and removes contaminants.

Contaminant Damage

▼ Orifice blockage

▼ Component wear

▼ Formation of rust or other oxidation

▼ Chemical compound formation

▼ Depletion of additives

▼ Biological growth

Hydraulic fluid is expected to create alubricating film to keep precision partsseparated. Ideally, the film is thickenough to completely fill the clearancebetween moving parts. This conditionresults in low wear rates. When thewear rate is kept low enough, a compo-nent is likely to reach its intended lifeexpectancy, which may be millions ofpressurization cycles.

Contamination Basics

2

Filtration FactProperly sized, installed, and

maintained hydraulic

filtration plays a key role

in machine preventative

maintenance planning.

Filtration FactThe function of a hydraulic

filter is to clean oil, but the

ultimate purpose is to

reduce operating costs.

Filtration FactThe disposal cost of a

drum of waste oil can be

4X - 5X the cost of a

drum of new oil.

Actual photomicrograph of particulate contamination (Magnified 100x Scale: 1 division = 20 microns)

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The actual thickness of a lubricatingfilm depends on fluid viscosity, appliedload, and the relative speed of the twosurfaces. In many components, mech-anical loads are to such an extremethat they squeeze the lubricant into avery thin film, less than 1 micrometerthick. If loads become high enough, thefilm will be punctured by the surfaceroughness of the two moving parts. The result contributes to harmful friction.

Contamination Basics

3

Micrometer Scale

Particle sizes are generally measuredon the micrometer scale. One microm-eter (or “micron”) is one-millionth ofone meter, or 39 millionths of an inch.The limit of human visibility is approx-imately 40 micrometers. Keep in mindthat most damage-causing particles inhydraulic or lubrication systems aresmaller than 40 micrometers.Therefore, they are microscopic andcannot be seen by the unaided eye.

Typical Hydraulic Component Clearances

Microns 0.5

0.5-10.5-5

1-41-255-40

18-6350-250

130-450

Component Anti-friction bearings Vane pump (vane tip to outer ring) Gear pump (gear to side plate) Servo valves (spool to sleeve) Hydrostatic bearings Piston pump (piston to bore) Servo valves flapper wallActuators Servo valves orifice

Relative Sizes of Particles

Inches.0039.0027.0016.0010.0003 .0001

Substance Grain of table salt Human hair Lower limit of visibility Milled flour Red blood cells Bacteria

Microns10070402582

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ParticulateContaminationTypes

Particulate contamination is generallyclassified as “silt” or “chips.” Silt canbe defined as the accumulation of particles less than 5�m over time. Thistype of contamination also causes system component failure over time.Chips on the other hand, are particles5�m+ and can cause immediate catastrophic failure. Both silt andchips can be further classified as:

Contamination Types and Sources

4

Filtration FactNew fluid is not necessarily

clean fluid. Typically, new

fluid right out of the drum is

not fit for use in hydraulic or

lubrication systems.

Filtration FactAdditives in hydraulic fluid

are generally well below

1 micron in size and are

unaffected by standard

filtration methods.

Hard Particles▼ Silica

▼ Carbon

▼ Metal

Soft Particles▼ Rubber

▼ Fibers

▼ Micro organism

Flow

1. Particulate Silt (0-5um) Chips (5um+)

Types of Contamination

2. Water (Free & Dissolved)

3. Air

Silt

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Damage

Sources

▼ Built-in during manufacturing andassembly processes.

▼ Added with new fluid.

If not properly flushed, contaminantsfrom manufacturing and assembly willbe left in the system.

These contaminants include dust,welding slag, rubber particles fromhoses and seals, sand from castings,and metal debris from machined com-ponents. Also, when fluid is initiallyadded to the system, contamination isintroduced.

During system operation, contamina-tion enters through breather caps,worn seals, and other system openings.System operation also generates inter-nal contamination. This occurs as component wear debris and chemicalbyproducts react with component sur-faces to generate more contamination.

Contamination Types and Sources

5

▼ Ingested from outside the systemduring operation.

▼ Internally generated during operation (see chart below).

Stress raisers causedby particle collisions

A B

C D

A. Three-body mechanical interactions canresult in interference.

B. Two-body wear is common in hydraulic components.

C. Hard particles can create three-body wear to generate more particles.

D. Particle effects can begin surface wear.

Abrasive Wear—Hard particlesbridging two moving surfaces,scraping one or both.

Cavitation Wear—Restrictedinlet flow to pump causes fluidvoids that implode causingshocks that break away criticalsurface material.

Fatigue Wear—Particles bridging a clearance cause a surface stress riser thatexpands into a spall due torepeated stressing of the damaged area.

Erosive Wear—Fine particles ina high speed stream of fluid eataway a metering edge or criticalsurface.

Adhesive Wear—Loss of oil filmallows metal to metal contactbetween moving surfaces.

Corrosive Wear—Water orchemical contamination in thefluid causes rust or a chemicalreaction that degrades a surface.

Generated Contamination

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Contamination Types and Sources

6

Filtration FactSystem ContaminationWarning Signals

• Solenoid burn-out.

• Valve spool decentering,

leakage, “chattering”.

• Pump failure, loss of

flow, frequent

replacement.

• Cylinder leakage, scoring.

• Increased servo hysteresis.

Filtration FactMost system ingression

enters a system through the

old-style reservoir breather

caps and the cylinder rod

glands.

Prevention

▼ Use spin-on or dessicant style filters for reservoir air breathers.

▼ Flush all systems before initial start-up.

▼ Specify rod wipers and replace worn actuator seals.

▼ Cap off hoses and manifolds during handling and maintenance.

▼ Filter all new fluid before it enters the reservoir.

External Contamination Sources

Mobile Equipment 108-1010 per minute*

Manufacturing Plants 106-108 per minute*

Assembly Facilities 105-106 per minute*

* Number of particles greater than 10 microns ingressedinto a system from all sources.

Ingression Rates For Typical Systems

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WaterContamination

Types

There is more to proper fluid maintenance than just removing particulate matter. Water is virtually auniversal contaminant, and just likesolid particle contaminants, must beremoved from operating fluids. Watercan be either in a dissolved state or ina “free” state. Free, or emulsified,water is defined as the water above thesaturation point of a specific fluid. Atthis point, the fluid cannot dissolve orhold any more water. Free water isgenerally noticeable as a “milky” discoloration of the fluid.

Contamination Types and Sources

7

50 PPM 2000 PPM

Typical Saturation Points

Hydraulic Fluid

Lubrication Fluid

Transformer Fluid

300

400

50

.03%

.04%

.005%

Fluid Type PPM %

1000 ppm(.10%)

300 ppm(.03%)

Visual Effects Of Water In Oil

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Damage

▼ Corrosion of metal surfaces

▼ Accelerated abrasive wear

▼ Bearing fatigue

▼ Fluid additive breakdown

▼ Viscosity variance

▼ Increase in electrical conductivity

Anti-wear additives break down in thepresence of water and form acids. Thecombination of water, heat and dissimilarmetals encourages galvanic action. Pittedand corroded metal surfaces and finishesresult. Further complications occur astemperature drops and the fluid has lessability to hold water. As the freezing point

is reached, ice crystals form, adverselyaffecting total system function. Operatingfunctions may also become slowed orerratic.

Electrical conductivity becomes a pro-blem when water contamination weakensthe insulating properties of a fluid, thusdecreasing its dielectric kV strength.

Contamination Types and Sources

8

Filtration FactA simple ‘crackle test’ will

tell you if there is free

water in your fluid. Apply a

flame under the container.

If bubbles rise and ‘crackle’

from the point of applied

heat, free water is present

in the fluid.

Filtration FactHydraulic fluids have the

ability to ‘hold’ more water

as temperature increases.

A cloudy fluid may become

clearer as a system

heats up.

Typical results of pump wear due to particulate and water contamination

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Sources

▼ Worn actuator seals

▼ Reservoir opening leakage

▼ Condensation

▼ Heat exchanger leakage

Fluids are constantly exposed to waterand water vapor while being handledand stored. For instance, outdoor stor-age of tanks and drums is common.Water may settle on top of fluid con-tainers and be drawn into the contain-er during temperature changes. Watermay also be introduced when openingor filling these containers.

Water can enter a system through worncylinder or actuator seals or throughreservoir openings. Condensation isalso a prime water source. As the fluidscool in a reservoir or tank, water vaporwill condense on the inside surfaces,causing rust or other corrosion problems.

Contamination Types and Sources

9

250

200

150

100

50

0

% Water In Oil0.0025

Effect of water in oil on bearing life (based on 100% life at .01% water in oil.)Reference: ”Machine Design” July 86, ”How Dirt And Water Effect Bearing Life” by Timken Bearing Co.

0.01 0.05 0.10 0.15 0.25 0.50

% B

eari

ng L

ife R

emai

ning

Effect Of Water In Oil On Bearing Life

0.0025%0.01%0.05%0.10%0.15%0.25%0.50%

=======

25 ppm 100 ppm 500 ppm1000 ppm1500 ppm2500 ppm5000 ppm

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Prevention

Excessive water can usually beremoved from a system. The same pre-ventative measures taken to minimizeparticulate contamination ingressionin a system can be applied to watercontamination. However, once exces-sive water is detected, it can usually be eliminated by one of the followingmethods:

Absorption

This is accomplished by filter elementsthat are designed specifically to takeout free water. They usually consist of alaminant-type material that transformsfree water into a gel that is trappedwithin the element. These elements fit

into standard filter housings and aregenerally used when small volumes ofwater are involved.

Centrifugation

Separates water from oil by a spinningmotion. This method is also only effective with free water, but for largervolumes.

Vacuum Dehydration

Separates water from oil through a vacuum and drying process. Thismethod is also for larger volumes ofwater, but is effective with both thefree and dissolved states.

Contamination Types and Sources

10

Filtration FactFree water is heavier than

oil, thus it will settle to the

bottom of the reservoir

where much of it can be

easily removed by opening

the drain valve.

Filtration FactAbsorption filter elements

have optimum

performance in low

flow and low viscosity

applications.

Vacuum dehydration system

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Air Contamination

Types

Air in a liquid system can exist ineither a dissolved or entrained (undis-solved, or free) state. Dissolved air maynot pose a problem, providing it staysin solution. When a liquid containsundissolved air, problems can occur asit passes through system components.There can be pressure changes thatcompress the air and produce a largeamount of heat in small air bubbles.This heat can destroy additives, andthe base fluid itself.

If the amount of dissolved air becomeshigh enough, it will have a negativeeffect on the amount of work performed by the system. The workperformed in a hydraulic system relieson the fluid being relatively incom-pressible, but air reduces the bulkmodulus of the fluid. This is due to thefact that air is up to 20,000 times morecompressible than a liquid in which itis dissolved. When air is present, apump ends up doing more work tocompress the air, and less useful workon the system. In this situation, thesystem is said to be ‘spongy’.

Damage

▼ Loss of transmitted power

▼ Reduced pump output

▼ Loss of lubrication

▼ Increased operating temperature

▼ Reservoir fluid foaming

▼ Chemical reactions

Air in any form is a potential source ofoxidation in liquids. This acceleratescorrosion of metal parts, particularlywhen water is also present. Oxidationof additives also may occur. Bothprocesses produce oxides which pro-mote the formation of particulates, orform a sludge in the liquid. Wear andinterference increases if oxidationdebris is not prevented or removed.

Sources

▼ System leaks

▼ Pump aeration

▼ Reservoir fluid turbulence

Prevention

▼ System air bleeds

▼ Flooded suction pump

▼ Proper reservoir design

▼ Return line diffusers

Contamination Types and Sources

11

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In order to detect or correct problems,a contamination reference scale isused. Particle counting is the mostcommon method to derive cleanlinesslevel standards. Very sensitive opticalinstruments are used to count thenumber of particles in various sizeranges. These counts are reported asthe number of particles greater than acertain size found in a specified volume of fluid.

The ISO 4406:1999 (InternationalStandards Organization) cleanlinesslevel standard has gained wide accep-tance in most industries today. Thisstandard references the number of par-ticles greater than 4, 6, and 14 microm-eters in a known volume, usually 1 mil-liliter or 100 milliliters. The number of4+ and 6+ micrometer particles isused as a reference point for “silt” par-ticles. The 14+ size range indicates thequantity of larger particles presentwhich contribute greatly to possiblecatastrophic component failure.

Fluid Cleanliness Standards

12

Filtration FactKnowing the cleanliness

level of a fluid is the basis

for contamination control

measures.

Filtration FactThe ISO code index

numbers can never

increase as the particle

sizes increase

(Example: 18/20/22).

All particle distributions

have more smaller than

larger particles.

An ISO classification of 19/16/13 can be defined as:

Particles> 4 microns (c)

Particles> 6 microns (c)

Particles> 14 microns (c)

ISO CODE 19 / 16 / 13

19

16

13

4+

6+

14+

2,500 - 5,000

320 - 640

40 - 80

Range Number Micron (c) Actual Particle Count Range (per ml)

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13

Fluid Cleanliness Standards

ISO 17/14/11 fluid (magnification 100x)ISO 22/19/17 fluid (magnification 100x)

ISO 4406 Chart

24 23222120191817161514131211109876

RangeNumber More than Up to and including

Number of particles per ml

80,00040,00020,00010,0005,0002,5001,300

640320160804020105

2.51.3.64 .32

160,00080,00040,00020,00010,0005,0002,5001,300

640320160804020105

2.51.3.64

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Component Cleanliness Level Requirements

Many manufacturers of hydraulic andload bearing equipment specify theoptimum cleanliness level required fortheir components. Subjecting compo-nents to fluid with higher contamina-tion levels may result in much shortercomponent life.

In the table below, a few componentsand their recommended cleanlinesslevels are shown. It is always best toconsult with component manufacturersand obtain their written fluid cleanli-ness level recommendations. Thisinformation is needed in order toselect the proper level of filtration. It may also prove useful for any

subsequent warrantyclaims, as it may drawthe line between nor-mal use and excessiveor abusive operation.

Fluid Cleanliness Required forTypical Hydraulic Components

Fluid Cleanliness Standards

14

ISOComponents Code

Servo control valves 17/14/11Proportional valves 18/15/12

Vane and piston 19/16/13pumps/motors

Directional & pressure 19/16/13control valves

Gear pumps/motors 20/17/14

Flow control valves, 21/18/15cylinders

New unused fluid 21/18/15

Filtration FactMost machine and hydraulic

component

manufacturers specify a

target ISO cleanliness

level to equipment in

order to achieve optimal

performance standards.

Filtration FactColor is not a good

indicator of a fluid’s

cleanliness level.

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Fluid Cleanliness Standards

15

SAE AS5049 Revision E (Table 1)Cleanliness Classes For Differential Particle Counts (Particles / 100 mL) (3)

00 0 1 2 3 4 5 6 7 8 9

10 11 12

Classes5 to 15 µm

125 250 500

1 000 2 000 4 000 8 000

16 000 32 000 64 000

128 000 256 000 512 000

1 024 000

15 to 25 µm

22 44 89

178 356 712

1 425 2 850 5 700

11 400 22 800 45 600 91 200

182 400

25 to 50 µm 50 to 100 µm >100 µm6 to 14 µm(c)

(1)(2) 14 to 21 µm(c) 21 to 38 µm(c) 38 to 70 µm(c) >70 µm(c)

4 8

16 32 63

126 253 506

1 012 2 025 4 050 8 100

16 200 32 400

1 2 3 6 11 22 45 90 180 360 720

1 440 2 880 5 760

0 0 1 1 2 4 8 16 32 64 128 256 512

1 024

(1) Size Range, Optical Microscope, based on longest dimension as measured per ARP598, APC Calibrated per ISO 4402:1991.(2) Size Range, APC Calibrated Per ISO 11171 or Electron Microscope, based on projected area equivalent diameter.(3) Classes and contamination limits identical to NAS 1638.

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The filter media is that part of the element which removes the contaminant. Media usually starts out in sheet form,and is then pleated to expose more sur-face area to the fluid flow. This reducespressure differential while increasingdirt holding capacity. In some cases,the filter media may have multiple layers and mesh backing to achievecertain performance criteria. Afterbeing pleated and cut to the properlength, the two ends are fastenedtogether using a special clip, adhesive,or other seaming mechanism. The mostcommon media include wire mesh, cellulose, fiberglass composites, orother synthetic materials. Filter mediais generally classified as either surfaceor depth.

Surface Media

For surface type filter media, the fluidstream basically has a straight throughflow path. Contaminant is captured onthe surface of the element which facesthe fluid flow. Surface type elementsare generally made from woven wire.Since the process used in manufactur-ing the wire cloth can be very accurate-ly controlled, surface type media have aconsistent pore size. This consistentpore size is the diameter of the largesthard spherical particle that will passthrough the media under specified testconditions. However, the build-up ofcontaminant on the element surfacewill allow the media to capture parti-cles smaller than the pore size rating.Likewise, particles that have a smallerdiameter, but may be longer in length(such as a fiber strand), may passdownstream of a surface media.

Depth Media

For depth type filter media, fluid musttake indirect paths through the materi-al which makes up the filter media.Particles are trapped in the maze ofopenings throughout the media.Because of its construction, a depthtype filter media has many pores ofvarious sizes. Depending on the distrib-ution of pore sizes, this media can havea very high captive rate at very smallparticle sizes.

The nature of filtration media and thecontaminant loading process in a filterelement explains why some elementslast much longer than others. In gener-al, filter media contain millions of tinypores formed by the media fibers. Thepores have a range of different sizesand are interconnected throughout thelayer of the media to form a tortuouspath for fluid flow.

Filter Media Types and Ratings

16

Filtration FactSurface media can be

cleaned and re-used. An

ultrasonic cleaner is

usually the best method.

Depth media typically

cannot be cleaned and

it is not re-usable.

Surface Media

74 m

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The two basic depth media types thatare used for filter elements are cellu-lose and fiberglass.

The pores in cellulose media tend tohave a broad range of sizes due to theirregular size and shape of the fibers. In contrast, fiberglass media consist offibers that are very uniform in size andshape. The fibers are generally thinnerthan cellulose fibers, and have a uni-form circular cross section. These typi-cal fiber differences account for theperformance advantage of fiberglassmedia. Thinner fibers mean more actu-al pores in a given space. Furthermore,thinner fibers can be arranged closertogether to produce smaller pores forfiner filtration. Dirt holding capacity,as well as filtration efficiency, areimproved as a result.

Filter Media Types and Ratings

17

Flow Direction

Depth Media

General Comparison Of Filter Media

Media Material

DirtHolding Capacity

Life In a System

InitialCost

Fiberglass

Cellulose (paper)

Wire Mesh

High

Moderate

Low

DifferentialPressure

Moderate

High

Low

High

Moderate

Moderate

Moderate

Low

High

CaptureEfficiency

High

Moderate

Low

Typical coarse fiberglass construction (100X)

Typical fine fiberglass construction (100X)

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The MultipassTest

The filtration industryuses the ISO 4572“Multipass TestProcedure” to evaluatefilter element perfor-mance. This procedureis also recognized byANSI* and NFPA**.During the MultipassTest, fluid is circulatedthrough the circuitunder precisely con-trolled and monitoredconditions. The differential pressureacross the test element is continuouslyrecorded, as a constant amount of con-taminant is injected upstream of theelement. On-line laser particle sensorsdetermine the contaminant levelsupstream and downstream of the testelement. This performance attribute(The Beta Ratio) is determined for several particle sizes. Three important element performancecharacteristics are a result of theMultipass Test:1. Dirt holding capacity.

2. Pressure differential of the test filter element.

3. Separation or filtration efficiency, expressed as a “Beta Ratio”.

Beta Ratio

The Beta Ratio (also known as the filtration ratio) is a measure of the particle capture efficiency of a filterelement. It is therefore a performancerating.

As an example of how a Beta Ratio isderived from a Multipass Test. Assumethat 50,000 particles, 10 micrometersand larger, were counted upstream(before) of the test filter and 10,000particles at that same size range werecounted downstream (after) of the testfilter. The corresponding Beta Ratiowould equal 5, as seen in the followingexample:

Filter Media Types and Ratings

18

Flow MeterDownstream

Sample

UpstreamSample

TestFilter

�P Gauge

Reservoir

Contaminant

Variable Speed Pump

Multipass TestFiltration FactFilter media ratings

expressed as a Beta Ratio

indicate a media’s particle

removal efficiency.

Filtration FactMultipass test results are

very dependent on the

following variables:

• Flow rate

• Terminal pressure

differential

• Contaminant type

# of particles upstream# of particles downstream

“x” is at a specific particle size

50,00010,000

= 5

Bx =

B10 =

* ANSI – American National Standards Institute** NFPA – National Fluid Power Association

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The example would read “Beta tenequal to five.” Now, a Beta Ratio number alone means very little. It is a preliminary step to find a filter’s particle capture efficiency. This efficiency, expressed as a percent, can be found by a simple equation:

So, in the example, the particular filtertested was 80% efficient at removing 10micrometer andlarger particles. Forevery 5 particlesintroduced to the filter at this sizerange, 4 weretrapped in the filtermedia. The BetaRatio/ Efficienciestable shows somecommon Beta Rationumbers and their corresponding efficiencies.

Filter Media Types and Ratings

19

Beta RatioDownstream

ParticlesUpstreamParticles

100,000 > (x) microns

Beta Ratio (x) Efficiency (x)

100,00050,000

100,0005,000

100,0001,333

100,0001,000

100,000500

100,000100

=

=

=

=

=

=

2

20

75

100

200

1000

50.0%

95.0%

98.7%

99.0%

99.5%

99.9%

50,000

5,000

1,333

1,000

500

100

Beta Ratios/Efficiencies

Beta Ratio Capture Efficiency (at a given particle size) (at same particle size)

1.01 1.0%

1.1 9.0%1.5 33.3%2.0 50.0%5.0 80.0%10.0 90.0%20.0 95.0%75.0 98.7%100 99.0%200 99.5%1000 99.9%

Efficiencyx = (1- 1 ) 100Beta

Efficiency10 = (1- 1 ) 100

= 80%5

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A number of interrelated system factors combine to determine propermedia and filter combinations. To accu-rately determine which combination isideal for your system all these factorsneed to be accounted for. With thedevelopment of filtration sizing soft-ware such as inPHorm, this informationcan be used to compute the optimalselection.However, in many instancesthe information available may be limited. In these cases “rules ofthumb”, based on empirical data andproven examples, are applied to try and get an initial starting point.

The charts on the following pages are designed for just those instances.Be aware that rules of thumb utilize“standard” values when looking at com-ponents, ingressions, and other systemparameters. Your specific system mayor may not fit into this “standard” classification.

One of the more important points ofthe charts is to emphasize element efficiency. Note that as less efficientelements are utilized, more passes arerequired to obtain the same ISO

cleanliness level as a more efficientelement. Secondly, the charts indicatethe effect of system pressure on therequired ISO code. As system pressureincreases, the oil film thicknessbetween component parts decreases.This reduction in clearance allowssmaller micron particles to have harmful effects.The charts attempt toprovide flexibility by providing severalpossible solutions for each compo-nent/system pressure combination.

Selection software such as inPHorm(shown left) can be an extremely usefultool in the selection and specificationof the proper filtration product. Withcomputer aided selection, the user canquickly determine the pressure lossacross a given element, and/or housingcombination, within specific operatingparameters. The tedious process ofplotting viscosity at various points and calculating a pressure drop is eliminated. Additionally, selection software can predict system perfor-mance and element life – ideal for predictive maintenance programs.

Filter Media Selection

20

Filtration FactThere is no direct

correlation between

using a specific media and

attaining a specific ISO

cleanliness classification.

Numerous other variables

should be considered, such

as particulate ingression,

actual flow through filters,

and filter locations.

How to use charts:1. Choose the appropriate chart for your

system, hydraulic or lubrication.

2. Starting in the left column, the components are listed by order of sensitivity. Find the most sensitive component used in your system.

3. Following the color band to the right of the component selected, choose thepressure range that the system operateswithin. This step is not required for lubrication systems.

4. Follow the color band to the right of thepressure range selected for the suggestedISO code for the system

5. To the right of the ISO code, in the same color band, are the media efficien-cies required for the corresponding filterplacements. Depending on the selectionthere will be one to three optionsavailable.

6. Be sure that the filter placements recommendation is on the same level as the media efficiency selected.

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Filter Media Selection

Component Type System Pressure Suggested Media Efficiency Number of Minimum FilterCleanliness Code Betax >200 Filter Placements Placements

2

5

2

2

2

5

10

2

5

2

5

5

10

2

5

10

2

5

5

10

5

10

5

10

10

20

10

5

10

17/14/12

16/13/11

16/12/10

18/15/13

18/14/12

17/14/11

19/16/14

18/16/14

18/15/13

20/17/15

19/17/14

19/16/13

21/18/16

20/17/15

20/17/14

<1000

1000-3000

>3000

<1000

1000-3000

>3000

<1000

1000-3000

>3000

<1000

1000-3000

>3000

<1000

1000-3000

>3000

Servo Valves

Proportional

Valves

Variable Volume

Pumps

Vane Pumps

Fixed Piston Pumps

Cartridge Valves

Gear Pumps

Flow Controls

Cylinders

1

2

1.5

2

1

1.5

2.5

1

2

1.5

2.5

1

2

0.5

1.5

2.5

1

2

0.5

1.5

1

2

1.5

2.5

1

2.5

1.5

0.5

1.5

P

P & R

P & O

P & R

P

P & O

P, R & O

P

P & R

P & O

P, R & O

P or R

P & R

O

P or R, & O

P, R & O

P or R

P & R

O

P or R, & O

P or R

P & R

P or R, & O

P, R & O

P or R

P, R & O

P or R, & O

O

P or R, & O

Hydraulic Systems

Component Type Suggested Media Efficiency Number of Minimum FilterCleanliness Code Betax >200 Filter Placements* Placements

1.5

1

2

0.5

1.5

2.5

2

2

5

2

5

10

16/13/11

17/14/12

18/15/13

Ball Bearings

Roller Bearings

Journal BearingsGear Boxes

P or R, & O

P or R

P & R

0

P or R, & O

P, R & O

Lubrication Systems

21

P = Full flow pressure filter (equalsone filtration placement)

R = Full flow return filter (equals onefiltration placement)

O = Off-line (flow rate 10% of reser-voir volume equals .5 of a filtra-tion placement)

* Number of filtration placements insystem, more placements are theoption of the specifier.

Page 24: HANDBOOK FILTRATION PARKER

Contaminant Loading

Contaminant loading in a filter ele-ment is simply the process of blockingthe pores throughout the element. Asthe filter element becomes blockedwith contaminant particles, there arefewer pores for fluid flow, and the pres-sure required to maintain flow throughthe media increases. Initially, the dif-ferential pressure across the elementincreases very slowly because there isan abundance of media pores for thefluid to pass through, and the poreblocking process has little effect on theoverall pressure loss. However, a pointis reached at which successive block-ing of media pores significantlyreduces the number of available poresfor flow through the element. At this point the differential pressureacross the element rises exponentially.The quantity, size, shape and arrange-ment of the pores throughout the

element accounts for why some elements last longer than others.

For a given filter media thickness andfiltration rating, there are fewer poreswith cellulose media than fiberglassmedia. Accordingly, the contaminantloading process would block the poresof the cellulose media element quickerthen the identical fiberglass media element.

The multilayer fiberglass media element is relatively unaffected by contaminant loading for a longer time.The element selectively captures thevarious size particles, as the fluid pass-es through the element. The very smallpores in the media are not blocked bylarge particles. These downstreamsmall pores remain available for thelarge quantity of very small particlespresent in the fluid.

Filter Element Life

22

Diffe

rent

ial P

ress

ure

Time

IncrementalLife

Element Contamination Loading Curve

Filtration FactAs an element loads with

contamination, the

differential pressure will

increase over time; slowly

at first, then very quickly

as the element nears it’s

maximum life.

Page 25: HANDBOOK FILTRATION PARKER

Filter Element Life Profile

Every filter element has a characteris-tic pressure differential versus contam-inant loading relationship. This rela-tionship can be defined as the “filterelement life profile.” The actual lifeprofile is obviously affected by the sys-tem operating conditions. Variations inthe system flow rate and fluid viscosityaffect the clean pressure differentialacross the filter element and have awell-defined effect upon the actual element life profile.

The filter element life profile is verydifficult to evaluate in actual operatingsystems. The system operating versusidle time, the duty cycle and thechanging ambient contaminant condi-tions all affect the life profile of the filter element. In addition, precise

instrumentation for recording thechange in the pressure loss across thefilter element is seldom available. Mostmachinery users and designers simplyspecify filter housings with differentialpressure indicators to signal when thefilter element should be changed.

The Multipass Test data can be used to develop the pressure differential versus contaminant loading relation-ship, defined as the filter element lifeprofile. As previously mentioned, suchoperating conditions as flow rate andfluid viscosity affect the life profile fora filter element. Life profile compar-isons can only be made when theseoperating conditions are identical andthe filter elements are the same size.

Then, the quantity, size, shape, andarrangement of the pores in the filterelement determine the characteristiclife profile. Filter elements that aremanufactured from cellulose media,single layer fiberglass media and multi-layer fiberglass media all have a verydifferent life profile. The graphic comparison of the three most commonmedia configurations clearly shows the life advantage of the multilayerfiberglass media element.

Filter Element Life

Element Types Life Comparison

23

00 5 10 15 20 25 30 35 40 45 50

102030

40

5060

7080

90 6

5

4

3

2

1

100

CAPACITY (GRAMS)

Cellulose MultilayerFiberglass

Single LayerFiberglass

DIF

FERE

NTI

AL

PRES

SURE

(PSI

)

DIF

FERE

NTI

AL

PRES

SURE

(bar

)

Page 26: HANDBOOK FILTRATION PARKER

Filter HousingsThe filter housing is the pressure vesselwhich contains the filter element. Itusually consists of two or more sub-assemblies, such as a head (or cover)and a bowl to allow access to the filterelement. The housing has inlet and out-let ports allowing it to be installed into afluid system. Additional housing featuresmay include mounting holes, bypassvalves and element condition indicators.

The primary concerns in the housingselection process include mountingmethods, porting options, indicatoroptions, and pressure rating. All, exceptthe pressure rating, depend on the phys-ical system design and the preferencesof the designer. Pressure rating of thehousing is far less arbitrary. This shouldbe determined before the housing styleis selected.

Pressure RatingsLocation of the filter in the circuit is theprimary determinant of pressure rating.Filter housings are genericallydesigned for three locations in a cir-cuit: suction, pressure, or return lines.One characteristic of these locations istheir maximum operating pressures.Suction and return line filters are generally designed for lower pressuresup to 500 psi (34 bar). Pressure filter

locations may require ratings from 1500

psi to 6000 psi (103 bar to 414 bar).

It is essential to analyze the circuit forfrequent pressure spikes as well assteady state conditions. Some housingshave restrictive or lower fatigue pressure ratings. In circuits with fre-quent high pressure spikes, anothertype housing may be required to prevent fatigue related failures.

Filter Housing Selection

24

Filtration FactAlways use an element

condition indicator with any

filter, especially those that

do not have a bypass valve.

Filtration FactAn element loading with

contaminant will continue

to increase in pressure

differential until either:

• The element is replaced.

• The bypass valve opens.

• The element fails.

Visual/electrical element condition indicator

Bypass valve Assembly

Pressure housing

Filter element

Inlet port

Drain port

Page 27: HANDBOOK FILTRATION PARKER

The Bypass Valve

The bypass valve is used to prevent thecollapse or burst of the filter elementwhen it becomes highly loaded withcontaminant. It also prevents pumpcavitation in the case of suction linefiltration. As contaminant builds up inthe element, the differential pressureacross the element increases. At apressure well below the failure point of the filter element , the bypass valveopens, allowing flow to go around theelement.

Some bypass valve designs have a“bypass to-tank” option. This allows theunfiltered bypass flow to return to tankthrough a third port, preventing unfil-tered bypass flow from entering thesystem. Other filters may be supplied

with a “no bypass” or “blocked”bypass option. This preventsany unfiltered flow from goingdownstream. In filters with nobypass valves, higher collapsestrength elements may berequired, especially in highpressure filters. Applicationsfor using a “no bypass” optioninclude servo valve and othersensitive component protection. When specifying anon-bypass filter design, makesure that the element has a dif-ferential pressure rating closeto maximum operating pressure of thesystem. When specifying a bypass typefilter, it can generally be assumed thatthe manufacturer has designed the

element to withstand the bypass valvedifferential pressure when the bypassvalve opens.

After a housing style and pressure rating are selected, the bypass valvesetting needs to be chosen. The bypassvalve setting must be selected beforesizing a filter housing. Everything elsebeing equal, the highest bypass cracking pressure available from themanufacturer should be selected. Thiswill provide the longest element life fora given filter size. Occasionally, a lowersetting may be selected to help minimize energy loss in a system, or toreduce back-pressure on another com-ponent. In suction filters, either a 2 or3 psi (0.14 bar or 0.2 bar) bypass valveis used to minimize the chance ofpotential pump cavitation.

Filter Housing Selection

25

950 psi(66 bar) 0 psi

(0 bar)

1000 psi(69 bar)1000 psi

(69 bar)

Filter(Elements Blocked)

Bypass valve50 psi setting

(3.4 bar)

Bypass Filter Blocked Bypass Filter

Flow

0

2

Beta Performance Lost by Cyclic Flow and Bypass Leakage.

Effe

ctiv

e Fi

ltrat

ion

Ratio

B10

4

6

Steady Flow–No Leakage

Unsteady Flow–No Leakage

8

10

0 2 4 6 8 10 12

12

Unsteady Flow–10% Leakage

Unsteady Flow–20% Leakage

Unsteady Flow–40% Leakage

B10 From Multipass Test

BetaLost byCyclicFlow

Page 28: HANDBOOK FILTRATION PARKER

Element ConditionIndicators

The element condition indicator signals when the element should becleaned or replaced. The indicator usu-ally has calibration marks which alsoindicates if the filter bypass valve hasopened. The indicator may be mechan-ically linked to the bypass valve, or itmay be an entirely independent differ-ential pressure sensing device.Indicators may give visual, electrical orboth types of signals. Generally, indica-tors are set to trip anywhere from 5%-25% before the bypass valve opens.

Housing And Element Sizing

The filter housing size should be largeenough to achieve at least a 2:1 ratiobetween the bypass valve setting andthe pressure differential of the filterwith a clean element installed. It ispreferable that this ratio be 3:1 or even higher for longer element life.

For example, the graph on the nextpage illustrates the type of catalogflow/pressure differential curves whichare used to size the filter housing. Ascan be seen, the specifier needs toknow the operating viscosity of thefluid, and the maximum flow rate(instead of an average) to make surethat the filter does not spend a highportion of time in bypass due to flowsurges. This is particularly importantin return line filters, where flow multi-plication from cylinders may increasethe return flow compared to the pumpflow rate.

Filter Housing Selection

26

Filtration FactAlways consider low tem-

perature conditions when

sizing filters. Viscosity

increases in the fluid may

cause a considerable

increase in pressure differ-

ential through the filter

assembly.

Filtration FactPressure differential

in a filter assembly

depends on:

1. Housing and

element size

2. Media grade

3. Fluid viscosity

4. Flow rate

Filtration FactIt is recommended to use

an element condition

indicator with any filter,

especially those that

do not incorporate a

bypass valve.

Filter Element Sizing

3:1 OptimumRatio

CleanElement

P

Diff

eren

tial P

ress

ure

LIFE

Filter Bypass

Cracking Pressure

Page 29: HANDBOOK FILTRATION PARKER

If the filter described in the graph wasfitted with a 50 psi (3.4 bar) bypassvalve the initial (clean) pressure dif-ferential should be no greater than 25psi (1.7 bar) and preferably 16 2¼3 psi(1.1 bar)or less. This is calculated fromthe 3:1 and 2:1 ratio of bypass settingand initial pressure differential.

Most standard filter assemblies utilizea bypass valve to limit the maximumpressure drop across the filterelement. As the filter element becomesblocked with contaminant, the pres-sure differential increases until thebypass valve cracking pressure isreached. At this point, the flowthrough the filter assembly beginsbypassing the filter element and passesthrough the bypass valve. This actionlimits the maximum pressure differen-tial across the filter element. Theimportant issue is that some of thesystem contaminant particles alsobypass the filter element. When thishappens, the effectiveness of the filterelement is compromised and theattainable system fluid cleanlinessdegrades. Standard filter assembliesnormally have a bypass valve crackingpressure between 25 and 100 PSI (1.7and 6.9 bar).

The relationship between the startingclean pressure differential across the

filter element and the bypass valvepressure setting must be considered.A cellulose element has a narrowregion of exponential pressure rise. For this reason, the relationshipbetween the starting clean pressuredifferential and the bypass valve pressure setting is very important. Thisrelationship in effect determines theuseful life of the filter element.

In contrast, the useful element life ofthe single layer and multilayer fiber-glass elements is established by thenearly horizontal, linear region of rela-tively low pressure drop increase, notthe region of exponential pressure rise.Accordingly, the filter assembly bypassvalve cracking pressure, whether 25 or75 PSI (1.7 or 5.2 bar), has relativelylittle impact on the useful life of thefilter element. Thus, the initial pressure differential and bypass valvesetting is less a sizing factor when fiberglass media is being considered.

Filter Housing Selection

27

Typical Flow/Pressure Curves For A Specific Media

0 25 50 75 100 125 150 200 225 250 275 300 325 350 375

0

0.25

0.5

0.75

1.

1.25

1.5

1.75

0

5

10

100 SUS200 SUS15

20

25

100 20 30 40 50 60 70 80 90 100Flow(GPM) (LPM)

(PSI

) Di

ffere

ntia

l Pre

ssur

e (B

ar)

3:1 RATIO▼ 50/3 = 16 2/3 psid (1.1 bar)

2:1 RATIO▼ 50/2 = 25 psid (1.7 bar)

▼ At 200 sus fluid, the maximum flowrange would be between 42 gpmand 54 gpm (159 lpm and 204 lpm)

Page 30: HANDBOOK FILTRATION PARKER

Filter Types and Locations

▼ Suction ▼ Return

▼ Pressure ▼ Off-line

Suction Filters

Suction filters serve to pro-tect the pump from fluidcontamination. They arelocated before the inletport of the pump. Somemay be inlet “strainers”,submersed in the fluid.Others may be externallymounted. In either case,they utilize relativelycoarse elements, due tocavitation limitations ofpumps. For this reason,they are not used as prima-ry protection against contamination.Some pump manufactures do not rec-ommend the

use of a suction filter. Always consultthe pump manufacturer for inletrestrictions.

Types & Locations of Filters

28

To System

Filtration FactSuction strainers are often

referred to by “mesh” size:

60 mesh = 238 micron

100 mesh = 149 micron

200 mesh = 74 micron

Filtration FactThe use of suction filters

and strainers has greatly

decreased in modern

filtration.

Pressure Filters

Pressure filters arelocated downstreamfrom the system pump.They are designed tohandle the systempressure and sized forthe specific flow ratein the pressure linewhere they are located.

Pressure filters areespecially suited forprotecting sensitivecomponents directly downstream fromthe filter, such as servo valves. Locatedjust downstream from the system pump,

they also help protect the entire systemfrom pump generated contamination.

To System

Suction Filter

Pressure Filter

Page 31: HANDBOOK FILTRATION PARKER

Return FiltersWhen the pump is a sensitive compo-nent in a system, a return filter maybe the best choice. In most systems,the return filter is the last compo-nent through which fluid passesbefore entering the reservoir.Therefore, it captures wear debrisfrom system working componentsand particles entering through worncylinder rod seals before such contaminant can enter the reservoirand be circulated. Since this filter islocated immediately upstream fromthe reservoir, its pressure rating andcost can be relatively low.

In some cases, cylinders with largediameter rods may result in “flowmultiplication”. The increased returnline flow rate may cause the filter

bypass valve to open, allowing unfiltered flow to pass downstream.This may be an undesirable conditionand care should be taken in sizing the filter.

Both pressure and return filters cancommonly be found in a duplex ver-sion. Its most notable characteristicis continuous filtration. That is, it ismade with two or more filter cham-bers and includes the necessary valving to allow for continuous, uninterrupted filtration. When a filter element needs servicing, theduplex valve is shifted, diverting flow to the opposite filter chamber.The dirty element can then bechanged, while filtered flow continues to pass through the filterassembly. The duplex valve typicallyis an open cross-over type, whichprevents any flow blockage.

Types & Locations of Filters

29

Cylinder has 2:1 ratio piston area to rod diameter.

Return line filter is sized for 66 gpm (250 lpm).Pressure is generally less than 25 psi (1.7 bar).

33 gpm(125 lpm)

Return LineFilters

Duplex Filter Assembly

Page 32: HANDBOOK FILTRATION PARKER

Off-LineFiltration

Also referred to as recir-culating, kidney loop, orauxiliary filtration, thisfiltration system is totallyindependent of amachine’s main hydraulicsystem. Off-line filtrationconsists of a pump, filter,electrical motor, and theappropriate hardwareconnections. These com-ponents are installed off-line as a small sub-system separate from the working lines, or included in a fluidcooling loop. Fluid is pumped out of thereservoir, through the filter, and back tothe reservoir in a continuous fashion.With this “polishing” effect, off-line fil-tration is able to maintain a fluid at aconstant contamination level. As with areturn line filter, this type of system isbest suited to maintain overall cleanli-

ness, but does not provide specific com-ponent protection. An off-line filtrationloop has the added advantage that it isrelatively easy to retrofit on an existingsystem that has inadequate filtration.Also, the filter can be serviced withoutshutting down the main system. Mostsystems would benefit greatly from having a combination of suction, pres-

sure, return, and off-line filters.The table to the right may behelpful in making a filtrationlocation decision.

Types & Locations of Filters

30

Filtration FactRule of thumb:

size the pump flow of an

off-line package at a

minimum of 10% of the

main reservoir volume.

Filtration FactThe cleanliness level of a

system is directly propor-

tional to the flow rate

over the system filters.

Pump

Off-LineFilter

Optional Cooler

Air breatherExisting

Hydraulicor LubeSystem

Off-Line Filter

Flow Rate Effect on Off-Line FiltrationPerformance

.01

.1

23/21/18

20/18/1519/17/14

18/16/1316/14/12

15/13/10

For beta rated filters witha minimum rating of beta (10) = 75

(Number of particles > 10 micron ingressing per minute)

Source based on Fitch, E.C., Fluid Contamination Control, FES, Inc., Stillwater, Oklahoma, 1988.

Num

ber o

f par

ticle

s up

stre

am p

er m

illili

tre g

reat

er th

an re

fere

nce

size

ISO

Corr

elat

ion

1

10

102

103

103 104 105 106 107 108 109 1010 1011 1012

104

105

106

Ingression rate

1 GP

M (3

.8 lpm

)

10 G

PM (3

8 lpm

)

10

0 GPM

(380

lpm)

Page 33: HANDBOOK FILTRATION PARKER

Types & Locations of Filters

31

Comparison of Filter Types and LocationsFILTERLOCATION ADVANTAGES DISADVANTAGES

Suction • Last chance • Must use relatively(Externally protection for the pump. coarse media,and/or largeMounted) housing size, to keep

pressure drop low due to pump inlet conditions.

• Cost is relatively high.• Much easier to • Does not protect

service than a downstream sump strainer. components from pump

wear debris.• May not be suitable for

many variable volume pumps.

• Minimum system protection.

Pressure • Specific component • Housing is relativelyprotection expensive because it

• Contributes to overall must handle full systemsystem cleanliness level. pressure.

• Can use high • Does not catch wearefficiency, fine filtration, debris from downstreamfilter elements. working components.

• Catches wear debris from pump

Return • Catches wear • No protection fromdebris from components, pump generatedand dirt entering contamination.through worn cylinder • Return line flow surgesrod seals before it enters may reduce filterthe reservoir. performance.

• Lower pressure • No direct componentratings result in lower protection.costs. • Relative initial cost

• May be in-line or is low.in-tank for easierinstallation.

Off-Line • Continuous “polishing” of • Relative initial cost is high.the main system hydraulic • Requires additional space.fluid, even if the system is • No direct component shut down. protection.

• Servicing possible withoutmain system shut down.

• Filters not affected by flowsurges allowing for optimumelement life and performance.

• The discharge line can be directed to the main system pump to provide superchargingwith clean, conditioned fluid.

• Specific cleanliness levelscan be more accurately obtained and maintained.

• Fluid cooling may be easilyincorporated.

Page 34: HANDBOOK FILTRATION PARKER

Fluid Analysis Methods

▼ Patch Test

▼ Portable Particle Counter

▼ Laboratory Analysis

Fluid analysis is an essential part ofany maintenance program. Fluid analy-sis ensures that the fluid conforms tomanufacturer specifications, verifiesthe composition of the fluid, and deter-mines its overall contamination level.

Patch Test

A patch test is nothing more than a visual analysis of a fluid sample. It usually involves taking a fluid sampleand passing it through a fine media“patch”. The patch is then analyzedunder a microscope for both color and

content, and compared to known ISOstandards. By using this comparison,the user can get a “go, no-go” estimateof a system’s cleanliness level.

Another lesser-used deviation of thepatch test would be the actual count-ing of the particles seen under themicroscope. These numbers wouldthen be extrapolated into an ISOcleanliness level.

The margin of error for both of thesemethods is relatively high due to thehuman factor.

Fluid Analysis

32

Filtration FactThe only way to know the

condition of a fluid is

through fluid analysis.

Visual examination is not

an accurate method.

Filtration FactAny fluid analysis should

always include a particle

count and corresponding

ISO code.

Typical test kit

Page 35: HANDBOOK FILTRATION PARKER

Portable Particle Counter

A most promising development in fluidanalysis is the portable laser particlecounter. Laser particle counters arecomparable to full laboratory units incounting particles down to the 2 +micron range. Strengths of this recenttechnology include accuracy, repeata-bility, portability, and timeliness. A testtypically takes less than a minute.Laser particle counters will generallygive only particle counts and cleanli-ness classifications. Water content, viscosity, and spectrometric analysistests would require a full laboratoryanalysis.

Laboratory Analysis

The laboratory analysis is a completelook at a fluid sample. Most qualifiedlaboratories will offer the followingtests and features as a package:

▼ Viscosity

▼ Neutralization number

▼ Water content

▼ Particle counts

▼ Spectrometric analysis (wear metals and additive analysisreported in parts per million,or ppm)

▼ Trending graphs

▼ Photo micrograph

▼ Recommendations

In taking a fluid sample from asystem, care must be taken tomake sure that the fluid sampleis representative of the system.To accomplish this, the fluidcontainer must be cleanedbefore taking the sample andthe fluid must be correctlyextracted from the system.

There is a National Fluid PowerAssociation (NFPA) standard forextracting fluid samples from a reservoir of an operating hydraulicfluid power system.(NFPA T2.9.1-1972).There is also the American NationalStandard method (ANSI B93.13-1972)for extracting fluid samples from thelines of an operating hydraulic fluidpower system for particulate contami-nation analysis. Either extractionmethod is recommended.

In any event, a representative fluidsample is the goal. Sampling valvesshould be opened and flushed for atleast fifteen seconds. The clean samplebottle should be kept closed until thefluid and valve is ready for sampling.The system should be at operating tem-perature for at least 30 minutes beforethe sample is taken.

A complete procedure follows in the appendix.

Fluid Analysis

Portable particle counter

Laboratory Analysis

33

FFLLUUIIDD AANNAALLYYSSIISS RREEPPOORRTT

SSAAMMPPLLEE DDAATTAA

COMPANY NAME: XYZ CorporationSYSTEM TYPE: Hydraulic SystemEQUIPMENT TYPE: LOADERMACHINE ID: x1111FILTER ID:

SAMPLE DATE: 06-01-94HOURS (on oil/unit): 100 / 100SYSTEM VOLUME: 20 LFLUID TYPE:CITGO AW 46ANALYSIS PERFORMED: AI-BSTV4 (W)

AAUUTTOOMMAATTIICC PPAARRTTIICCLLEE CCOOUUNNTT SSUUMMMMAARRYY

W A R N I N G1. The recommended CLEANLINESS Code is not met.

Clean-up maintenance may be warrant.

2. Dotted graph line indicates recommended ISO Code level.

CleanlinessCode

Size Counts per ml.

> 2 µm 353242.0> 5 µm 34434.0> 10 µm 2342.0 26/22/14> 15 µm 154.0> 25 µm 17.0> 50 µm 1.0

FFRREEEEWWAATTEERR

PPRREESSEENNTT

YES

NOX

PARTEST Fluid Analysis ServiceParker Hannifin Corporation16810 Fulton County Road #2Metamora, OH 43540Tele:(419)644-4311Fax:(419)644-6205

SAMPLE CODE: 1034 DATE: 06-01-94XYZ Corporation12345 Middleton Rd.Anywhere USA 41114Attn:

SIZE (microns)

30

29

28

27

26

25

24

23

22

21

20

19

18

17

16

15

14

13

12

11

10

9

8

7

6

5

4

3

2

12 5 10 15 20 25 30 40 50 60 80 100

107

5.04.03.0

2.01.5

106

5.04.03.02.01.5

105

5.04.03.0

2.01.5

104

5.04.03.02.01.5

103

5.04.03.02.01.5

102

5.04.03.02.01.5

101

5.04.03.0

2.01.5

100

5.04.03.02.01.5

10-1

5.04.03.02.01.5

10-2

Number

of

particles

per

ml

>

size

IISSOO CCHHAARRTT RANGECODE

RREEMMAARRKKSS

PPHHOOTTOO AANNAALLYYSSIISSMag.: 100x Vol.: 20 ml Scale: 1 div = 20 µm

Page 36: HANDBOOK FILTRATION PARKER

SAMPLINGPROCEDUREObtaining a fluid sample for particlecounts and/or analysis involves impor-tant steps to make sure you are gettinga representative sample. Often erroneous sampling procedures willdisguise the true nature of systemcleanliness levels. Use one of the following methods to obtain a representative system sample.

I. For systems with asampling valveA. Operate system for a least 1/2 hour.B. With the system operating, open thesample valve allowing 200 ml to 500 ml(7 to 16 ounces) of fluid to flush thesampling port. (The sample valvedesign should provide turbulent flowthrough the sampling port.)C. Using a wide mouth, pre-cleanedsampling bottle, remove the bottle cap and place in the stream of flowfrom the sampling valve. Do NOT“rinse” out the bottle with initial sample. Do not fill the bottle morethan one inch from the top.D. Close the sample bottle immediate-ly. Next, close the sampling valve.(Make prior provision to “catch” thefluid while removing the bottle fromthe stream.)E. Tag the sample bottle with perti-nent data: include date, machine number, fluid supplier, fluid numbercode, fluid type, and time elapsedsince last sample (if any).

II. Systems without asampling valve

There are two locations to obtain asample in a system without a sampling valve: in-tank and in the line. The procedure for both follows:

A. In the Tank Samplingl. Operate the system for at least 1/2 hour.2. Use a small hand-held vacuumpump bottle thief or “bastingsyringe” to extract sample. Insertsampling device into the tank to onehalf of the fluid height. You will prob-ably have to weight the end of thesampling tube. Your objective is toobtain a sample in the middle por-tion of the tank. Avoid the top or bot-tom of the tank. Do not let thesyringe or tubing came in contactwith the side of the tank.3. Put extracted fluid into anapproved, pre-cleaned sample bottleas described in the sampling valvemethod above.4. Cap immediately.5. Tag with information as describedin sampling valve method.

B. In-Line Sampling1. Operate the system for at least 1/2 hour.2. Locate a suitable valve in the system where turbulent flow can beobtained (ball valve is preferred). Ifno such valve exists, locate a fittingwhich can be easily opened to pro-vide turbulent flow (tee or elbow).3. Flush the valve or fitting samplepoint with a filtered solvent. Openvalve or fitting and allow adequateflushing. (Take care to allow for thisstep. Direct sample back to tank orinto a large container. It is not necessary to discard this fluid.)

Appendix

34

Page 37: HANDBOOK FILTRATION PARKER

35

Appendix

4. Place in an approved and pre-cleaned sam-ple bottle under thestream of flow per sampling valve methods above.5. Cap sample bottleimmediately.6. Tag with importantinformation per thesampling valve method.Note: Select a valve orfitting where the pressure is limited to200 PSIG (14 bar) orless.

Regardless of the methodbeing used, observe com-mon sense rules. Anyequipment which is usedin the fluid sampling procedure must bewashed and rinsed with afiltered solvent. Thisincludes vacuum pumps,syringes and tubing. Yourgoal is to count only theparticles already in thesystem fluid. Dirty sampling devices andnon-representative samples will lead to erroneous conclusionsand cost more in the long run.

Model xxxx Lab Report xxxxElement xx Date xxFlow 30 Gpm Tested By xxxFab.Int. 10 In Water Acftd Batch xxxFluid Mil-H-5606/Shell Asa-3 Counts On-Line

98/102F;14.77-15.3 C

Diff. Press. (PSID) INJECTION FLUIDTerminal 235.0 Grav (MG/L) Flow (L/Min)Clean Ass’y 5.0 Initial 1226.8 7 PointHousing 3.2 Final 1279.4 AverageElement 1.8 Average 1253.1 0.453NET 233.2System Gravimetrics (MG/L): Base: 5.0 Final: 11.8

% Net Time Delta P. Grams Inject. Particle Distribution Analysis-Part./H SizeAss’y Added Flow (Up/Down/Beta) Particle SizeElem’t 2 3 5 7 10 12

Clean 4.89 2.22 1.11 0.89 0.22 0.00Fluid 8.32 1.75 0.44 0.00 0.00 0.002.5 25.4 10.8 14.4 0.451 13,178.00 6,682.00 2,678.00 1,382.00 643.30 436.10

7.6 10,168.00 2,863.00 340.30 39.55 3.18 0.231.30 2.33 7.85 34.9 200 1,900

5 31.1 16.7 17.7 0.455 14,060.00 7,214.00 2,822.00 1,427.00 673.00 463.2013.5 11,056.03 3,391.00 406.48 35.91 1.59 0.23

1.27 2.13 6.94 39.7 420 2,00010 35.8 28.3 20.3 0.455 13,900.00 7,207.00 2,817.00 Upstream Particle Count

25.1 10,590.00 3,274.00 395.301.31 2.20 7.13

20 39.0 51.6 22.1 0.453 14,950.00 7,833.00 3,201.00 Downstream Particle Count48.4 9,496.00 2,869.00 375.00

1.57 2.73 8.54 Test Point Beta Ratio40 42.6 98.3 24.2 0.455 12,410.00 6,696.00 2,857.00 1,495.00 700.70 474.68

95.1 7,843.00 2,277.83 380.58 38.83 1.82 0.461.58 2.94 9.51 49.8 390 1,000

80 45.1 191.6 25.6 0.453 11,420.00 6,299.00 2,768.00 1,456.00 681.10 469.30188.4 6,152.00 1,709.00 234.30 32.28 5.46 2.50

1.86 3.69 11.8 45.1 120 190100 45.9 238.2 26.1 0.451 11,130.00 6,136.00 2,717.00 1,427.00 669.40 460.90

235.0 6,013.00 1,690.00 262.50 41.14 8.87 5.231.85 3.63 10.4 34.7 75.5 88.1

Minimum Beta: Ratio’s 1.27 2.13 6.94 32.6 75.5 88.1Time Avg. Beta Ratio’s 1.36 2.42 7.97 37.2 220 800

Anti-static Additive In Test Fluid

Element PressureDrop At TestTermination

Test Point Information

% of Net �Psi

Duration of Test (Minutes)

Assembly �Psi

Element �Psi

CumulativeCapacity(Grams)

Injection Flow(Liters/Min)

Final Capacity (Grams): Apparent: 26.1 Retained: 25.8

Minimum Beta Ratio ForParticle Size During Test

Weighted Avg Beta Ratio For Cumulative Dirt Added Calculated AmountParticle Size Over Test Duration During Test Of Grams Retained

Sample Multipass Lab Report

Page 38: HANDBOOK FILTRATION PARKER

Appendix

36

V i s c o s i t y C o n v e r s i o n C h a r t

M e t r i c C o n v e r s i o n T a b l e

TO CONVERT INTO MULTIPLY BY

Inches Millimeters 25.40Millimeters Inches .03937Gallons Liters 3.785Liters Gallons .2642Pounds Kilograms .4536Kilograms Pounds 2.2046PSI Bar .06804Bar PSI 14.5Centigrade Fahrenheit (�C x 9¼5) +32Fahrenheit Centigrade (�F - 32) /1.8Microns Inches .000039Microns Meters .000001

cSt (Centistokes) SUS (Saybolt Universal Seconds)*10 4620 9325 11630 13932.4 15040 18550 23270 32490 417

Comparisons are made at 100° F (38° C). For other viscosityconversion approximations, use the formula: cSt =

* NOTE: Saybolt universal seconds may also be abbreviated SSU.

SUS4.635

Page 39: HANDBOOK FILTRATION PARKER

Appendix

37

Viscosity vs. Temperature

2000

1000 500

200

100 50 20 10 8 6 4 3 2

1.5 1 .9 .8 .7 .6

-60

-40

-20

020

4060

8010

015

020

025

030

035

040

050

0

-51

-40

-29

-18

-74

1627

3852

6693

121

149

204

260 10

,000

5,00

0

1,00

0

500

250

100

50 40 35

Kinematic Viscosity—Centistokes

Viscosity—Saybolt Universal Seconds

Tem

pera

ture

�F

Tem

pera

ture

�C

SAE 6

0SA

E 50

Bunke

r "C"

& SA

E 50

Hydr

aulic

Flui

d M

IL-O

-560

6

MIL-

L-780

8

AN-0-9 G

rade

1010

No. 4 F

uel

No. 3 Fu

el

No. 2 F

uel

Diesel

Fuel

JP-5

Kero

sene

JP-4

Avera

geAvia

tion G

asoli

ne—

Avera

ge

SAE 7

0SA

E 40

SAE 3

0

SAE 2

0SA

E 10

Page 40: HANDBOOK FILTRATION PARKER

Parker Hannifin CorporationHydraulic Filter Division16810 Fulton County Road #2Metamora, OH 43540Phone: (419) 644-4311Fax: (419) 644-6205http://www.parker.com/filtration

Catalog HTM-410M, 10/05, T&M Printed in USA

Contact Parker’s worldwide service and distribution network by calling:

Argentina • +54 (1) 752 4129Australia • +61 (2) 634 7777Austria • +43 (2622) 23501 3Belgium • +32 (2) 762 1800Brazil • +55 (11) 3917 1407Canada • 1-800-272-7537China • +86 (21) 6249 9755 Czech Republic • +42 (2) 752544Denmark • +45 (43) 541133Finland • +358 (0) 8784211France • +33 (50) 258025Germany • +49 (69) 311096Hong Kong • +852 2428 8008Hungary • +36 (1) 25 22 539India • +91 (22) 577 1671Italy • +39 (2) 451921Japan • +81 (45) 861-3811Korea • +82 (2) 561 0414Mexico • 1-800-272-7537Netherlands • +31 (5410) 85000New Zealand • +64 (9) 573 1523Norway • +55 (99) 867760Poland • +48 (22) 461455Singapore • +65 261 5233South Africa • +27 (11) 9703630Spain • +34 (1) 6757300Sweden • +46 (8) 760 2960Taiwan • +886 (2) 781 3206United Arab Emirates • +971 (2) 788587United Kingdom • +44 1924 487000 United States of America • 1-800-272-7537Venezuela • +58 (2) 238 5422

Parker Worldwide Sales Offices

Filtration Group Technical Sales & Service Locations

Finite Filter Division500 Glaspie StreetOxford, MI 48371Phone: (248) 628-6400Fax: (248) 628-1850

Hydraulic Filter Division16810 Fulton County Road #2Metamora, OH 43540Phone: (419) 644-4311Fax: (419) 644-6205

Process Filter Division1515 W. South StreetP.O. Box 1300Lebanon, IN 46052Phone: (765) 482-3900Fax: (765) 482-8410

Racor Division3400 Finch RoadP.O. Box 3208Modesto, CA 95353Phone: (800) 344-3286Phone: (209) 521-7860Fax: (209) 529-3278

Racor DivisionHydrocarbon ProductsRoute #3 Box 9Henryetta, OK 74437Phone: (918) 652-4481Fax: (918) 652-8882

Filter Division U.K.Churwell ValeShaw Cross Business ParkDewsbury, England WF12 7RDPhone: +44 1924 487000Fax: +44 1924 487060

Filter Division U.K.UCC ProductsP.O. Box 3Thetford, NorfolkIP24 3RT EnglandPhone: (44) 1842-754251Fax: +44 1842-753702

Finn Filter DivisionFin-31700Urjala As., FinlandPhone: (358) 3 54 100Fax: (358) 3 54 10100

Parker Hannifin Ind. e Com.Ltda. Filter DivisionVia Anhanguera, Km. 25,305276-977 – São Paulo– SP, BrazilPhone: +55 (11) 847 1222Fax: +55 (11) 847 1610

Parker Hannifin Asia PacificCompany, LTD902 Dae Heung Bldg.648-23 Yeoksam-dongKangnam-ku, Seoul,Korea 135-080Phone: 82 2 561 0414Fax: 82 2 556 8187