filter microns

GTS-200rev 7/05

Filter MediaTechnology

Media Choices: Purely synthetic or Duratek™,our blend of synthetic and natural fibers

Our exclusive Spider-Web® Nanofiber Technology is available on either media

Choose Media to Conquer Your Challenging Environment

Learn why Lowest ∆P is Important!

Specially Formulated to ProtectGas Turbines, Compressors and Generators

Take a Close Look at Donaldson Filter Media

Duratek™ (Donaldson’s proprietary blend of natural &synthetic fibers) -- Synthetic fibers mixed in add strength andmoisture resistance.

In these photos taken with our scanning electron microscope (SEM), you’re seeing filter media magnified200, 500, or 1000 times! Note the pore size (spaces between the fibers) and the construction of the fibers(smooth, rough, large, small.)

Duratek™ with Spider-Web® -- Adding DonaldsonSpider-Web®, our patented layer of nanofibers, over the Duratek™

substrate creates very small pore sizes, enabling entrapmentof very small (even sub-micron!) particulate.

Synthetic (Donaldson’s man-made filter media) -- Bycontrolling the fiber diameter and the pore size, we candesign filter media to be effective in various environments(desert, arctic/frost, urban, industrial, marine, etc.)The smooth fibers provide low impedance to airflow --helping to maintain low ∆P for the entirelife of the filter.

Synthetic with Spider-Web® -- Note the ‘web’ of ourpatented nanofiber technology bonded over the synthetic substrate.This media formulation has proven to be the most effective filtersolution for gas turbine protection......best filtering efficiency, bestpulsing characteristics, best ∆P over the life of the filter.

Examine the heart of the filter system -- the filter media.

And Now It’s Dirty -- Spider-Web® catches most of the very fine particulate, allowing two majorbenefits: (a) very fine particles that cause fouling (those less than 5µmin size) are more effectively captured, and (b) pulse-cleaning is moreeffective due to the surface-loading characteristics of the Spider-Web®

layer. (This photo shows Synthetic/Spider-Web®; the surface loadingcharacteristics are the same for Duratek/Spider-Web®.)

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Premium Protection:Synthetic MediaOur man-made fibers, with theircontrolled fiber diameter and poresize, result in superior dust-holdingcapacity and low impedence toairflow. It helps keep ∆P lowthroughout the entire life of thefilter, which typically ranges from2 to 4 years depending on theharshness of the environment.Synthetic media is sturdy anddurable, even under normal-filter-killing conditions such as consistentor prolonged moisture, sticky/wethydrocarbons, salt, or very dusty/sandy.

Synthetic media is the basis for thebest filtration performance in mostcases.

Donaldson Offers a Wide Choice of MediaSo That You Can Choose the Best Filter for Your Particular Environment!

Outstanding Protection:Duratek™ MediaOur special blend of synthetic andnatural fibers, which we callDuratek™, is designed to resist theintermittant moisture that powerplants and oil/gas field operationsso often deal with, such as morningdew and coastal storms. Becauseof the synthetic fibers and theaddition of certain resins,Duratek™ withstands harshconditions, including high humidityand wet tropical environments.This cost-effective blend offers low∆P, little or no media swelling/bunching, and high dust holdingcapacity.

Increase Media Powerby Adding Spider-Web®

Spider-Web® is Donaldson’sproprietary & patented nanofibertechnology that catches very fine(even sub-micron!) particulatebefore it reaches the mediasubstrate. Spider-Web® is atreatment that is bonded to asubstrate -- either synthetic orDuratek™ filter media.

As you can see in the photos ofmedia (magnified 100’s of times) onthe previous page, the Spider-Web®

layer is made of fibers so fine thatthey don’t impede airflow, yet arestrong enough to capture very smallparticles. This is important formost turbine installations becausethe particles smaller than 5µ arethe ones that cause fouling of thecompressor blades. Spider-Web®

protects your turbine fromexcessive and premature fouling.

And now, even higher performanceis available in our Spider-Web® XPoption. Learn mor about it on page5 of this document.

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Better turbine protectionLess blade foulingHigher turbine outputLess maintenance costImproved turbineavailability

What can better air filtration mean to your

operation?

Superior - Recommendedwhen highest filtrationefficiency is needed.

Matching Filter Mediato Your Environmental ChallengeDonaldson Media Choices: Synthetic/

Spider-WebXPSynthetic/

Spider-Web Synthetic Duratek/Spider-Web Duratek

Desert: Arid; frequently heavywindblown dust concentration. Superior Satisfactory Satisfactory Recommended Adequate

Arid/Semi-Arid with frequentseasonal ground fog. Superior Recommended Satisfactory Satisfactory Adequate

Arctic: very cold, dry air; snowand frost frequently build up onfilters. Superior Satisfactory Satisfactory Recommended Adequate

Urban/industrial : Variety ofcontaminants, includingmoderate amounts ofhydrocarbons.

Superior Satisfactory Satisfactory Recommended Adequate

Marine, coastal , tropical andsemi-tropical (i.e., hot, humid,moisture-laden) environments Superior Recommended Satisfactory Satisfactory Adequate

Recommended - Good filterlife, good filtration efficiency,and best operating character-istics and economic value forthis environment.

Adequate - Reasonable filterlife and adequate filtrationefficiency.

Satisfactory - Reasonable orgood filter life with better thanadequate filtration efficiency,but may not offer the bestoperating characteristics andeconomic value for thisenvironment.

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Donaldson Spider-Web is the firstfilter media to effectively combinevery high filter efficiency with lowairflow restriction both initiallyand throughout the life of thefilter.

The result is better turbineprotection, lower overall turbineoperating costs and higher turbineavailability.

Spider-Web AdvantagesSurface-LoadingDonaldson’s patented Spider-Web mediatechnology consists of a “web” of sub-micron diameter fibers bonded to a substrateof Donaldson cellulose or synthetic filtermedia. The nanofiber web significantlyimproves the media’s ability to collect dustparticles on its surface, and minimizes thenumber of particles that penetrate into itsdepth. In traditional filter media withoutSpider-Web, particle ingress shortens filterservice life.

DurabilityThe patented nanofiber web is extremelydurable, as well as resistant to moisture andhigh temperature. This robust nanofiberlayer protects the turbine and deliverssuperiorself-cleaning performance throughout the lifeof the filter.

Low Pressure DropIncoming air passes through the Spider-Weblayer without increasing filter pressure drop.Spider-Web fibers are very small comparedto the airflow passages between mediafibers. Particles collect on the Spider-Weblayer, keeping the media pores open. Intraditional filter media, dust particles lodgein the pores between fibers and becomeimbedded in the media depth. Eventuallypores plug, causing filter pressure drop toincrease.

High EfficiencyInitiallyTraditional filters have an initial periodduring which filter efficiency must build upto peak levels, but Spider-Web filters arehighly efficient from the time they areinstalled. Spider-Web media accelerates theforming of a dust cake on the media surface,bringing the efficiency to nearly 100% veryquickly.

Because its fibers are less than 0.3µm in size,Spider-Web minimizes the number of fineparticles that pass through the media duringseasoning.Throughout filter service lifeSpider-Web’s unique surface loadingcapabilities cause incoming dust particles tocontinuously build up on the media’s surfacerather than its depth, thereby maintaininghigh efficiency and extending filter servicelife.

On Sub-Micron ParticlesAnother advantage of Spider-Web is itsability to capture sub-micron size particles.Because Spider-Web is made up of a tight‘web’ of sub-micron diameter fibers, it ismuch more efficient than traditional filtermedia at collecting dust particles less thanone micron in diameter.

Performance Improvementsfor Pulse-Cleaned FiltersBetter Dust Particle ReleaseDust particles are more easily dislodged duringpulse cleaning, because they load on the surfaceof Spider-Web filter media rather than in itsdepth. In traditional filter media, dust particlesbecome lodged in media pores, making itdifficult to remove them during the pulse-cleaning process.

Improved TurbineAvailabilityThe improved pulse cleaning performance ofSpider-Web filters results in fewer planned andunplanned maintenance outages for filterreplacement. This extended filter life, and thereduction in the amount and frequency ofturbine cleaning provides improved turbineavailability.

Lower, Stabilized PressureDropSpider-Web’s improved dust particle releasecapabilities result in a lower, stabilized filterpressure drop. The pressure drop of a pulse-cleanfilter system with Spider-Web filters stabilizes ata lower level than the same filter system withtraditional filters, because the media’s surfaceloading properties greatly improve dust particlerelease during the pulse-cleaning operation.

This photo fromour ScanningElectron Micro-scope showsSpider-Webmedia magnified2500 times! Notethe nanofiber‘web’ over thefilter mediasubstrate.

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To furtherenhance filter

efficiency on sub-micron particulate, Donaldson has developedand patented Spider-Web XP.Spider-Web XP features the web of sub-micron diameter fibers onboth sides of the filter media substrate. Thanks to this uniquedesign, initial filter efficiency is improved. For urban andindustrial locations with high concen-tration of particles belowone micron in size,Spider-Web XP offers superior turbine protection against fouling.

Spider-Web® XP reduces blade fouling significantly by capturingmore particulate that is smaller than 2µm. Tests on DonaldsonGDX filter pairs show (see graph below) that Donaldson Spider-Web XP reduces by about HALF the sub-micron particulate thatpenetrates through to reach the turbine blades compared toregular Spider-Web. And, Spider-Web XP captures FOUR TIMESas much sub-micron particulate particulate than a standard"blended" media (such as our Duratek).

The secret to this extra performace is bonding our patentedSpider-Web® nanofibers in very thin but robust layers on bothsides of the substrate media.The nanofibers are what enhance filter efficiency, especially onparticles smaller than 1 µm, the ones the are primarily responsiblefor compressor fouling.

As shown in these photos of the media (taken with our scanningelectron microscope at 500X magnification) the larger fibers aresandwiched between layers of very fine fibers. This triple-layer iswhat makes Donaldson Spider-Web® XP the most effective filtermedia for gas turbine protection!

GDX Element Pair* Tested at1630 cubic feet per minute (cfm), or0.77 cubic metres per second (cms)

*One conical & one cylindrical together

Choose Spider-Web XPfor Premium Performance

0.0

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SAE Fine Dust Loading (grams)

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∆∆∆∆∆P with SAE Fine Test Dust Load

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Initial Efficiency by Particle Size

Donaldson Spider-Web XP mediaDonaldson Duratek Spider-Web mediaDonaldson Duratek media (no Spider-Web)

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Air Filter Classification Equivalency TableMeeting global standards: ASHRAE 52.1, EN 1779,Eurovent 4/5, BS 6540, DIN 24 185

FilterType Eurovent EN779

ASHRAE52.1

Efficiency

MeasuredBy

forCoarse

Dust

EU1 G1* <65%

SyntheticDust

WeightArrestance

EU2 G2* 65<80%

EU3 G3* 80<90%

EU4 G4* >90%

forFine Dust

EU5 F5** 40<60%

Atmo-spheric

Dust SpotEfficiency

EU6 F6** 60<80%

EU7 F7 80<90%

EU8 F8 90<95%

EU9 F9 >95%

EuropeanHEPA

Standards

EU10 H10 85%

SodiumChloride or

LiquidAerosol

EU11 H11 95%

EU12 H12 99.5%

EU13 H13 99.95%

EU14 H14 99.995%

US HEPAStandard 99.97% DOP test

MIL Std 282

MERV:MinimumEfficiencyReportingValues(ASHRAE Standard52.2)

Microns(Log Scale)

0.001 0.01 0.1 1.0 10 100 1000

HumanHair

SAE Fine Dust

SAE Coarse Dust

Mist

Tobacco Smoke Coal Dust

Milled Flour

Pollen

BacteriaVirus

Colloidal Silica

Carbon Black

Diesel Soot

AqueousSalts

MetalIons

AtomicRadii

RelativeSize of

CommonMaterials

DOP Test

Beach Sand

Lint

Donaldson®

Atomized NaCl

Scanning ElectronMicroscope

OpticalMicroscope

Visible toNaked Eye

By: Mark Gogins

TestAerosols

MoldSporesSmog

Relative Dust/Particle Sizes

How Big is a Micron?As a unit of measure, 1 micron also called micro meter) =1 millionth of a meter or .000039 inch.

Symbol = µm

Size examples of familiarparticles:100µm = Grain of table salt

(.004 inch )40µm = Lower limit of visibility

(.0015 inch)10µm = Talcum powder

(.0004 inch)2µm = Bacteria (.00008 inch)

>90%>90%>90%>95%

>85%>85%>85%>90%

20% – 34.9%35% – 49.9%50% – 69.9%70% – 84.9%

Less than 20%Less than 20%Less than 20%Less than 20%

(E3)Composite Avg. Particle

Size Efficiency (PSE)3.0 – 10.0 Microns

––––

>90%>90%>90%>95%

Less than 75%75% – 84.9%85% – 94.9%

>95%

MERV 13MERV 14MERV 15MERV 16

4

––––

Less than 50%50% – 64.9%65% – 79.9%80% – 89.9%

––––


3

––––

––––

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2

<65%65% – 69.9%70% – 74.9%

>75%

––––

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1

AverageArrestance byASHRAE 52.1

Method





MERVRatingGroup

>90%>90%>90%>95%

>85%>85%>85%>90%

20% – 34.9%35% – 49.9%50% – 69.9%70% – 84.9%




––––

>90%>90%>90%>95%

Less than 75%75% – 84.9%85% – 94.9%

>95%


4

––––

Less than 50%50% – 64.9%65% – 79.9%80% – 89.9%

––––


3

––––

––––

––––


2

<65%65% – 69.9%70% – 74.9%

>75%

––––

––––


1


Method




>90%>90%>90%>95%

>85%>85%>85%>90%

20% – 34.9%35% – 49.9%50% – 69.9%70% – 84.9%




––––

>90%>90%>90%>95%

Less than 75%75% – 84.9%85% – 94.9%

>95%


4

––––

Less than 50%50% – 64.9%65% – 79.9%80% – 89.9%

––––


3

––––

––––

––––


2

<65%65% – 69.9%70% – 74.9%

>75%

––––

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1


Method





MERVRatingGroup

* Tested per EN 779** Efficiency @ 0.4 µm

HEPA = High EfficiencyParticulate Air Filter

Salt 100µµµµµm

Talc 10µµµµµm

Bacteria2µµµµµm

Visbility40µµµµµm

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Pre-Filters

Pre-filters -- both wraps andpanels -- have the job of

extending the life of the primaryfilter by capturing largerparticulate, such as seeds, leaves,airborne fibers,etc. They aremade of low-cost,relatively lowefficiencymaterials, anddesigned to bechanged moreoften than primary filters, andthrown away. (Cleaning andreusing them is neverrecommended.)

The filter media Donaldson usesfor our most popular pre-filtersare made of polyester fibers, airlaid (aka dry laid) in a randomly-oriented fashion to form a web.

Our pre-filter wrap is a “high loft”media, meaning it has quite a bitof air space between the fibersthroughout the depth of the mediamat, yet is visibly thicker & morerobust than competitive offerings.This enables good airflow throughthe wrap even after it hascaptured much particulate.

Our pre-filter panel is made oflonger, rather coarse fibers,packed more densely than thewrap media. The higher packingdensity enables good pleating,good effici-ency on largerparticulate,and strength.Choose eitherbeverageboardor metalframe.

PROBLEM: One of our customersin Canada was seeing fast foulingof the compressor, which led toloss of turbine output. This meantloss of revenue!

ANALYSIS: Since they had twoturbines running side-by-side, thecusomter decided to testDonaldson filters against the‘brand X’ commodity filtersthey’d been using. They chose toinstall Donaldson filter cartridgesmade with Spider-Web® (ourexclusive & proprietary fine fibermedia technology) to capture themajority of the very fine dirtparticles that they suspected hadbeen fouling the compressor.Both the brand X and Donaldsonfilters were new & clean at thebeginning of the test.

Why Sub-Micron Size Dirt Can Hurt!(a true story from one of our customers)

Actual photos taken by our customer of a section of bladefrom the 3rd stage of the stator

A) After 2360 operational hours, theblades behind ‘brand X’ are fouled --and causing turbine output loss!

B) After 2360 operational hours, theblades behind the filters with DonaldsonSpider-Web® are still clean -- andmaintain-ing turbine output at optimallevels!

CONCLUSION: After 2360operating hours, the stator bladeson the turbine behind brand Xwere black with fouling, asshown in photo A. Atthe same time, the blades behindSpider-Web® were still clean &shiny! (photo B)

LONG-TERM BENEFIT: Customermeasured their increased ouputfrom the turbine protected bySpider-Web® filters, as illustratedin the graph below. Increasedoutput value = OVER $100,000 peryear! The extra $6200 they paidfor a full set of Spider-Web filters(over the price of the commodityfilters) was an investment thatpaid for itself in the first 2 monthsof operation!

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0

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0 20 40 60 80

Operation Days

% P

ower

Los

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DonaldsonCompetition

XLR, GDX, GDS, GTM, Spider-Web, Spider-Web XP, Duratek, and Pleatloc are tradenames of the Donaldson Company, Inc.Donaldson Company, Inc. reserves the right to change or discontinue any model or specification at any time and without notice.Copyright 2005. Printed in U.S.A. An Equal Opportunity Employer

Corporate HeadquartersServing the AmericasDonaldson Company, IncPO Box 1299, 1400 W. 94th St.Minneapolis MN 55440 USAPhone: 1-952-887-3131Fax: 1-952-887-3843email: [email protected]

European HeadquartersServing Europe, Africa, Middle EastDonaldson Europe, BVBAResearch Park Zone 1, Interleuvenlaan 1B-3001 Leuven, BelgiumPhone: +32-16-38-3940Fax: +32-16-38-3939email: [email protected]

Donaldson Middle-East OfficeAbu Dhabi, United Arab EmiratesPhone: 00 971-6 7 45-2238

Donaldoson Gesellschaft m.b.H.Dulmen, GermanyPhone: +49 25 94 78 10

Asia/Pacific HeadquartersServing the Asia/Pacific RegionDonaldson Filtration Asia Pacific Pte LtdNo. 3, Changi Business Park Vista #02-00Singapore 486051Phone: 65-6311-7373Fax: 65-6311-7398email: [email protected]

Donaldson Australasia Pty. Ltd.New South Wales, AustraliaPhone: 61-02-4352-2022

DI Filter Systems Pvt. Ltd.New Delhi, IndiaPhone 0091-124-229-0350

Donaldson Shanghai OfficeShanghai, Peoples Republic of ChinaPhone 86-21-5425-3508

Donaldson Far East Ltd.Hong KongPhone 852-2402-2830

Nippon Donaldson, Ltd.Tokyo, JapanPhone: 81-42-540-4112

Donaldson Korea Company, LtdSeoul, Republic of KoreaPhone: 82-2-517-3333

www.donaldson.comWhere to Find Us:

Improving on Already-Great Filtration: PowerCoreHow can anyone improve on filtermedia that’s as highly efficient asSpider-Web? One way we’ve foundis to package it differently.

Traditionally, Donaldson filtermedia is dimpled and pleated tocreate more filter surface area in arelatively small space. Our newestmedia packaging technique, calledPowerCore, uses layers of corru-gated media (our normal syntheticor Duratek with Spider-Web) tocreate even more filtering surface --which gives us flexibility relative tofilter shape and size. PowerCorefilters can offer same/similarfiltering power in a smallerpackage, or more filtering power inthe same/similar size package.PowerCore filters can be square,oval, or round.

This is a pairof panel filters usedin the new Donaldson XLRinlet filtration system. Because ofPowerCore technology, XLR provideshigh performance with only half asmany filters as our GDX system.

Volvo FL6 mediumduty trucks use thiscompact ob-round-shaped PowerCorefilter to save space.

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