1 Hydroflow Filtration Systems F I L T R A T I O N S Y S T E M S HYDROFLOW SURFACE FILTRATION Versus DEPTH FILTRATION In Metalworking Fluids SURFACE

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Hydroflow Filtration SystemsF I L T R A T I O N S Y S T E M S

HYDROFLOW

SURFACE FILTRATION Versus DEPTH FILTRATION In Metalworking Fluids

SURFACE FILTRATION, refers to a method which traps particulate on the surface of a disposable or permanent filter media. The solids in the fluid need to stack up on each other and build a filter cake to increase the effectiveness and efficiency of the system. In flat bed vacuum or pressure filters, the performance depends on the nature of the solids, the distribution of the particle sizes and the velocity thought the media. Generally, 15-20 Micron is the best level of filtration on flat bed, surface filters – ROLL MEDIA OR PERMANENT MEDIA VACUUM AND PRESSURE FILTERS

DEPTH FILTRATION, refers to a method which traps particles throughout the cross-section of the filter medium. These are also referred to as Pre-Coat Filters. In the case of the Star Filter, the medium is the cellulose “filter aid” which provides a wide distribution of particles, establishes an effective filter cake and provides great dirty holding capacity. Because of the many types and grades of available filter-aids, Pre-Coat Filters can provide filtration to 1 Micron. PRECOATED PRESSURE FILTERS, STAR FILTER

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HYDROFLOW

A Wide Distribution Of

Particle Size And Shape

Creates The Best Filter Cake

And Yields High Filter Efficiency

Coarse Grinding, Aluminum Oxide Wheels Conventional and Creep Feed Grinding, Where A Mix Of Material And Wheel Brake Down Is Present

BUILDING A FILTER CAKE

Filter Cake

Filter Media Or Septum

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HYDROFLOW

A Narrow Distribution Of

Particle Size And Shape

Seals Off The Filter Media

Which Results In Less Dirt Holding

And Increase Operation Cost

Fine Grinding, Honing

Diamond & CBN Wheels

Cast Iron, Carbide, Glass & Ceramics

SURFACE BLINDING

Surface BlindingFilter Media Or Septum

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HYDROFLOW

A Filter Aid Can Be Used To

“Precoat” The Filter Septum

Creating A Filter Cake For Trapping

The Fine Particulate

FILTER AIDS - PRECOAT

Precoat FilterFilter Media Or Septum

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HYDROFLOW

THE KEY INGREDIENTS TO BUILDING A CAKE:

Good Distribution Of Solids

Large Amount Of Filter Area

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HYDROFLOW

In Cake Building applications, The amount of dirt a given area can hold is based on the flow rate or velocity through the media

FILTER AREA

Low Flow Allows The Cake To Build, Keeping The Paths Open For Additional

Flow To Pass and Dirt to be captured

10 Square Feet Of Filter Area.

High Flow Causes The Cake To Compress, Restricting The Paths,

Leading To Premature Loading

1 Square Foot Of Filter Area.

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HYDROFLOW

Permanent Or Disposable Roll Media

Reduces The Ability To Build A Cake And Leads To Surface Blinding And Reduced Efficiency

Heavy Dirt Load And / Or A Poor Distribution Of Particle Shape & Size

FLAT BED SURFACE FILTRATION

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HYDROFLOW

Contaminates Are Trapped Within The Cake

Cellulose Filter Aid Creates A True Depth Cake

Which Increases Dirt Holding Capacity And Filtration Efficiency

STAR FILTER DEPTH FILTRATION

MIC

RO

SC

RE

EN

S

EP

TU

M

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HYDROFLOW

The New Media Quickly “Blinds Off” Resulting In Rapid Regenerations

Regeneration Cycle Introduces Small Section Of New Media

Flow Takes The Path Of Least Resistance, Quickly Coating The New Section

FLAT BED FILTER REGENERATION

Permanent Or Disposable Roll Media

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HYDROFLOW

The Entire Filter Area Is Renewed And Recoated So The Velocity Stays Low Resulting In Long Efficient Filter Cycles

Increase In Vacuum Compress The Filter Cake, Restricting Flow

A Gentile Backwash Of Clean Fluid Releases The Compact Filter Cake

The Dense Filter Cake, Laden With Solids Quickly Settles To The Conveyor

STAR FILTER REGENERATION CYCLE

Documents

1 Hydroflow Filtration Systems F I L T R A T I O N S Y S T E M S HYDROFLOW SURFACE FILTRATION Versus DEPTH FILTRATION In Metalworking Fluids SURFACE