Basket & Screen Data - W&O Supply, Inc.

Basket & Screen DataCylindrical baskets for simplex and duplexstrainers up to 8" sizeBasket and Screen DesignScreen ConstructionThe basket or screen is theheart of an Eaton Strainer andis designed to be both effective and durable to perform itsfunction correctly. Eatonsupplies baskets and strainersin both standard and heavyduty designs. Standard designbaskets meet the needs ofmost applications. The heavyduty design design is usedmost often in applications withhigher viscosity liquids.Y strainer screens are rolled toform a perfect cylinder and areinduction welded along theseam. A neat weld must beapplied along the perforatedsheet seam to prevent thepossible bypass of solids andto provide a seam of acceptable strength. Eaton Y-Strainerscreen seats are machined tospecific dimensions and,accordingly, both the O.D. andlength of these screens areclosely toleranced.Eaton Baskets and screensare available in two standardmaterials: 1) Type 316 stainless steel and 2) Monel. Thesematerials cover nearly allcorrosion resistance levelsneeded in strainer services. Awide range of perforations andmesh provides removal ofsolids from 1/2" down to aslow as 40 micron. For special,unique applications Eaton cancustom fabricate a basketfrom just about any material toyour exact specifications.Basket ConstructionSlant top baskets for Model 510 simplex and Model 570 duplex strainerssizes 8" to 36"Each style basket includes aperforated sheet which isinduction welded to a rigid topring and solid bottom cap.Special attention is paid to thewelds along the perforatedsheet seam to prevent thepossible bypass of solids andto maintain the basket’sstrength. A handle is thenwelded to the I.D. of the topring to facilitate easy removal.Heavy duty baskets have reinforcing strips inductionwelded along the perforation’sseam and circumferentially onthe outside of the mid-sectionof the basket. The perforatedsheet is placed inside the topring and bottom cap as well.Perforated Sheet—SpecificationAll Eaton baskets and screensare made of perforated sheet.The percentage of open areaof a screen generally dictatesthe internal pressure drop thatwill be experienced across it.Other factors, though, mustbe taken into consideration toproduce a screen that willprovide a reasonable servicelife. The objective is to selecta perforation with the bestbalance of open area, holearrangement and sheetthickness.Eaton baskets are made usingperforated sheet with roundholes because of its greaterinherent strength and resistance to stress cracking.Pleated basket for Model 72simplex and Model 50 duplexstrainers sizes 10" to 18"24EATON FILTRATION Standard Cast Pipeline Strainers

Open AreaPerforationsPerforated sheet can have anopen area from 15% to 75%.In general, the larger the openarea of perforated sheet, thethinner the sheet thicknessmust be. As holes arepunched closer together toincrease the perforated openarea, the solid portionbetween holes distorts andbecomes weak. Table A onpage 27 describes the sheetthickness which is used toconstruct baskets andscreens.Eaton baskets and screens areavailable in 1/32", 3/64", 1/16",1/8", 5/32", 1/4", 3/8" and 1/2"perforations and in meshsizes: 20, 40, 60, 80, 100, 200and 325. However, over manyyears we have found that forgeneral service there is oneperforation for each size andtype of strainer which is mostpopular. This is called thestandard perforation and is thesize furnished with thestrainer unless anotherperforation is specified.Another factor in controllingthe sheet thickness is thehole diameter. The smaller thehole diameter, the thinner thesheet. The rule of thumb usedby commercial perforatedsheet manufacturers is thathole dimensions smaller thanthe plate thickness areimpractical and costly tomanufacture. Eaton basketsand screens have between28% to 63% open area withgauge thickness from 18(0.048") to 25 (0.021"),depending upon the size ofthe perforations and the sizeand model ofthe strainer.Hole ArrangementHoles can be punched in astraight line or in a staggeredpattern. Eaton baskets andscreens have a staggeredpattern which increases theopen area, provides extrastrength and creates lesspressure drop.Wire Mesh SpecificationsPartial cutaway of plug type duplex strainershowing basket in positionAll Eaton strainers areavailable with woven wiremesh screens. Wire meshprovides smaller openingsthan can be obtained byperforating for very finestraining applications downto 40 micron.Woven mesh is constructedsimilarly to fabric and is wovenon machines like those usedin the textile industry.Eaton baskets and screens aremade using monofilamentmesh having equal wire sizeand wire count in bothdirections to produce squareopenings. Other types ofmesh such as Dutch (orHollander) are also available.Dutch weave has a greaterquantity of wires in onedirection and fewer wires of alarger diameter in the otherdirection. This creates arectangular opening. As withperforated sheet, the bestwire mesh selection is abalance of open area, wirediameter and type of weave.Cutaway of Y strainer shows strainer screenin positionWe have standardized certainmesh sizes based on pastexperience which we feel willprovide the best strainer operation and longest life.Cone type temporary strainer is shown boltedbetween two pipe flangesEATON FILTRATION Standard Cast Pipeline Strainers25

Basket & Screen DataPattern ExamplesStaggered HolesStraight Holes1/32"1/16"1/8"1/4"Plain Dutch WeaveStandard wire mesh linersfor Eaton baskets and screensare available from 20 mesh to400 mesh. For any size mesh,there are several differentopen area selections basedon the diameter of the wiresused. Twenty mesh means20 wires per inch in both avertical and horizontaldirection. Therefore, as thewire size increases, the holesize decreases. Eaton basketsoffer wire mesh with openingsfrom 0.034" to 0.0015" (20mesh to 400 mesh).Woven in an over and underpattern in one direction wherethe horizontal wires are largerin diameter than the verticalwires which are driven closeand crimped at each pass.This weave produces greaterstrength, but lower flowrates than a square weave.Most often used in steamapplications.Open Area– Actual SizeThe open area of wire mesh isa function of both the weaveand the wire diameter. Eatonuses a plain square weave inmost cases because itsstraight-through flow pathcreates the least pressuredrop. In almost all cases, themesh is reinforced with aperforated metal backinghaving greater than a 60%open area. This combinationaffords the greatest degree ofstrength, yet offers a lowerpressure drop than othertypes of wire mesh.– Actual Size– Actual Size– Actual SizeMagnetic strainerelement capturesmicroscopic iron andsteel particles26OpeningsEATON FILTRATION Standard Cast Pipeline StrainersIn certain instances, such as Ystrainer in steam applications,the increased pressure dropresulting from the use of aDutch weave is not as criticalas the retention of smallparticles. Therefore, inapplications which involvesteam, Eaton suggests theuse of weave such as the 30 x160 size which can withstanda much higher differentialpressure without bursting.Eaton can supply baskets andscreens having open areasfrom 14% to 46%.Plain Square WeaveWoven in an over and underpattern of wire having thesame diameter. This weaveproduces a square openinghaving excellent flowcharacteristics.Mesh Liners AvailableThe size of mesh liners isdetermined by the numberof openings per linear inch.The standard sizes Eatoncan furnish are 20, 40, 60,80, 100, 200, 325 and 400.Magnetic InsertsAlthough a mesh lined Eatonstrainer basket will catch andremove very small unwantedparticles (down to 400 mesh),there are applications wheremicroscopic iron or steelparticles are present in thefluid. Being so tiny they willoften pass through the finestmesh screen. The problem isparticularly prevalentwhenever there is wear of ironor steel parts against eachother in the system. Examplesare cooling or lubricating linesto bearings, liquids beingprocessed on rolls or rollermills such as paint or ink, andany material passing through agear system.A simple, cost effective way toremove these damage-causingparticles is to install magneticinserts in the Eaton strainerbasket. All the fluid passesover the powerful magnetswhich catch those fine steel oriron particles which mightotherwise pass through themesh lining of the basket. Themagnets are Alnico,guaranteed to retain theirmagnetism indefinitely, and sopowerful they will hold metalseveral times their ownweight. They are completelyencased and sealed in a 1/8"thick type 316 stainless steelshell—thus assuring freedomfrom contamination orcorrosion.

Wire Mesh WeavesTable A. Perforated Basket Sheet nessUSS Gauge #26HolePatternStraight%Open d52.01/226Staggered47.9Plain Square WeaveTable B. Mesh Basket Sheet ches0.0340MeshOpeningMicrons864%Open 836.0MeshSize20Plain Dutch WeaveMesh Liners20 Mesh40 Mesh60 Mesh80 MeshEATON FILTRATION Standard Cast Pipeline Strainers27

Basket Effective AreaStrainerModel30R28Pipe Size1-1/2PerforationSize5/32Nominal Areaof Pipe (sq in)2.03Gross ScreenArea (sq in)35.4Free Area (sq in)22.3Ratio Free Areato Pipe 8501-1/21/82.0339.719.09.45021/83.3564.030.79.2502 2.0345.022.010.653BTX21/83.3565.031.09.353BTX2 ATON FILTRATION Standard Cast Pipeline Strainers

materials: 1) Type 316 stain-less steel and 2) Monel. These materials cover nearly all corrosion resistance levels needed in strainer services. A wide range of perforations and mesh provides removal of solids from . 1 / 2" down to as low as 40 micron. For special, unique applications Eaton can custom fa