Pleated filter element
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A Metal Pleated Filter Element is a rigid, self-supporting filter made entirely of metal, typically stainless steel (most common: 304, 316, 316L), but sometimes also nickel or other specialty alloys. The key feature is its pleated design, which creates a large surface area within a compact housing.The filter media itself is a sintered metal powder or a fine metal mesh, formed into a thin sheet and then folded into precise pleats. This construction allows for high dirt-holding capacity and consistent filtration performance.
Characteristics
Extreme Durability: They are mechanically strong and can withstand high differential pressures, pressure shocks, and vibrations without collapsing.
High Temperature Resistance: They can operate continuously at temperatures exceeding 500°C (932°F), making them ideal for hot gas filtration.
Chemical Compatibility:Stainless steel and specialty alloys offer excellent resistance to a wide range of chemicals, solvents, and corrosive process streams.
Reusable & Cleanable: This is a major advantage. Unlike disposable filters, metal pleated elements can be cleaned multiple times (via back-pulsing, ultrasonic cleaning, or chemical baths) and reinstalled, leading to a lower total cost of ownership over time.
Their robust construction allows for a very long operational life, even with repeated cleaning cycles.
Precise Filtration: They are available in very fine absolute micron ratings, often down to 0.5 microns or even smaller for some mesh types.
Construction and Materials
Media:
Sintered Metal Powder: Metal powder is sintered (heated without melting) to create a porous sheet. This provides a depth filtration effect with a labyrinthine pore structure, offering high dirt-holding capacity.
Woven Wire Mesh: Multiple layers of fine stainless steel mesh are often laminated together. This provides a more surface-type filtration and can achieve very fine ratings.
Pleats: The media is precision-pleated to ensure uniform flow and maximize surface area.
Core and Cage: The pleat pack is supported by an internal core (center tube) and often an external cage to prevent pleat deformation under pressure.
End Caps:The element is sealed with metal end caps, typically welded to create a robust, leak-proof unit.
Common Filtration Ratings
Metal pleated elements are available in a wide range of absolute and nominal micron ratings. Common ratings include:
Coarse:40, 25, 10 microns
Medium: 5, 3 microns
Fine: 1, 0.5 microns (and even sub-micron for specialized mesh elements)
Applications
Metal pleated filters are used wherever conditions are too harsh for polymer or cellulose filters.
1.Chemical & Petrochemical Industry
2.Oil & Gas Industry
3.Power Generation
4.Pharmaceutical & Bio-Tech
5.Food & Beverage
6.Hydraulics & Lubrication
7.Pulp & Paper
Cleaning and Maintenance
The ability to clean these filters is critical.Common methods include:
Backflushing/Back-Pulsing:
The most common method.
Clean fluid or air is pumped in the reverse direction to dislodge the filter cake.
Often automated in-place.
Ultrasonic Cleaning:
Effective for deep-seated contaminants.
The element is placed in an ultrasonic bath.
ChemicalCleaning/Soaking:
Using solvents or detergents to dissolve specific contaminants.
ThermalDegreasing:
Baking the element in an oven to burn off organic residues.
Important:
The cleaning method must be chosen based on the contaminant to avoid damaging the delicate media.Performance should be
verified after cleaning by abubble point test or other integrity test.
Summary:
Metal Pleated Filter Elements are the premium choice for demanding filtration tasks.While their upfront price is higher,their
exceptional durability,reusability,and performance under extreme conditions of temperature,pressure,andcorrosion make them an
economically superior and technically essential solution for countless critical industrial processes.
