Filter Cartridges

Cartridge Construction Types

Industrial filter cartridges fall into two fundamental categories based on how they capture particles: depth filtration and surface filtration.

Depth Filtration Cartridges

Depth cartridges capture particles throughout the full thickness of the filter media, not just at the surface. They have high dirt-holding capacity and long service life, making them well suited for applications with moderate to heavy particulate loads.

Melt-Blown Cartridges are manufactured by blowing molten polypropylene fibers onto a core, creating a graded-density structure that is denser at the center and more open at the outside. This gradient captures progressively finer particles as liquid moves inward, which maximizes dirt-holding capacity and extends cartridge life. Melt-blown cartridges are the most common depth cartridge for general industrial use. Eaton's LOFTREX series is the industry standard.

String Wound / Wound Depth Cartridges are manufactured by winding yarn or fiber around a central core in a pattern that creates a depth filtration matrix. They are economical, effective for coarse to medium filtration, and available in a variety of fiber materials including cotton, polypropylene, and polyester.

Surface Filtration Cartridges

Surface cartridges capture particles on the outer layer of the filter media. They offer more precise particle retention than depth cartridges and are available in both nominal and absolute ratings.

Pleated Cartridges have a folded pleated media structure that provides the largest surface area of any cartridge style. More surface area translates to higher flow rates, lower initial pressure drop, and longer service life between replacements. Pleated cartridges are available in polypropylene, polyester, glass microfiber, and PTFE media. Eaton's LOFPLEAT and LOFPLEAT AG series are designed for standard and high-purity applications respectively.

High Flow Pleated Cartridges are oversized pleated cartridges designed for systems that require very high flow rates with fewer elements. They reduce the total number of cartridges needed, which simplifies change-outs and lowers housing size requirements. Eaton's LOFPLEAT HF series is designed for these applications.

Membrane Cartridges provide absolute-rated filtration, meaning they remove a validated percentage of particles at a specific micron size. Membrane cartridges are used in applications where precision and regulatory compliance are required, such as pharmaceutical, biotech, and high-purity water processing. Available in polyethersulfone, PTFE, nylon, and polypropylene membrane media. Eaton's LOFMEM series covers this category.

Specialty Cartridges

Activated Carbon Cartridges use carbon media to adsorb dissolved chemicals, chlorine, taste, and odor from liquids. They are commonly used in water treatment, food and beverage, and process water polishing applications.

Stainless Steel Cartridges are cleanable, reusable cartridges for high-temperature or high-pressure applications where disposable media is not practical.

Resin-Bonded Fiber Cartridges use a rigid, bonded fiber structure for consistent flow and particle retention. They do not release fibers into the filtrate, making them suitable for applications where media migration is a concern.

How to Select the Right Filter Cartridge

Step 1: Match Your Housing

The cartridge must physically fit your housing. Key specifications to match:

Specification	Common Options
Cartridge length	9.75 in. or 10 in., 20 in., 30 in., 40 in.
Cartridge diameter	Approximately 2.5 in. standard, 4.5 in. big blue, 6 in. and larger high flow
End cap configuration	DOE double open end, 222 flat, 222 fin, 226 flat, 226 fin, Code 3, Code 7
Seal material	Silicone, EPDM, Buna-N, Viton, FKM

Step 2: Choose Your Filtration Type

• Depth filtration, including melt-blown and wound cartridges, for general-purpose filtration with high dirt-holding capacity
• Surface filtration, including pleated cartridges, for higher flow, longer life, and more precise particle retention
• Membrane filtration for absolute-rated filtration where validated removal is required
• Specialty cartridges, including carbon, stainless, and resin-bonded cartridges, for specific contaminant removal or reusability

Step 3: Select Your Micron Rating

The micron rating determines the smallest particle size captured. Lower micron means finer filtration but also more flow restriction. If you are unsure, start coarser and work finer until you achieve the desired result.

• Sub-micron to 1 micron for fine particle and bacteria-level removal using membrane or high-efficiency pleated cartridges
• 1 to 10 micron for fine industrial filtration using pleated or melt-blown cartridges
• 10 to 50 micron for general process protection using pleated, melt-blown, or wound cartridges
• 50 to 100+ micron for coarse pre-filtration and equipment protection

Step 4: Confirm Material Compatibility

The cartridge media and seal materials must be compatible with your process liquid and operating temperature. Polypropylene is the standard for most water and mild chemical applications. Polyester and glass microfiber handle higher temperatures. PTFE and specialty membranes are used for aggressive chemicals. Always verify chemical compatibility before ordering.

Performance and Maintenance

Filter cartridges are consumable components replaced on a regular cycle. Monitor the differential pressure across the housing to determine when cartridges need to be changed. A recommended change-out threshold is approximately 30 PSI of differential pressure, though this varies by cartridge type and application.

Additional indicators that a cartridge needs replacement:

• Reduced flow rate through the system
• Visible decline in product quality or clarity
• The cartridge has reached the end of its manufacturer-recommended service interval

Replacing cartridges too early wastes usable life. Replacing them too late risks contaminant bypass, reduced product quality, or physical damage to the cartridge element.

Shop by Brand and Series

Eaton Filtration

• LOFTREX - Melt-blown polypropylene depth cartridges. The industry standard for general industrial liquid filtration.
• LOFTREX-M - Modified melt-blown cartridges with enhanced construction for higher performance applications.
• LOFPLEAT - Pleated polypropylene surface cartridges for high flow and extended service life.
• LOFPLEAT AG - Pleated cartridges for high-purity applications with absolute-rated options.
• LOFPLEAT HF - High flow pleated cartridges for systems requiring maximum flow with fewer elements.
• LOFMEM - Membrane cartridges for absolute-rated filtration in pharmaceutical, biotech, and high-purity water.

Graver Technologies

• QMC Series - High-performance pleated cartridges available in multiple media types and end cap configurations.

Harmsco

• Hurricane - Up-flow cartridge filters with patented design for improved filtration efficiency and reduced air entrapment.

Shelco Filters

• Melt-blown, pleated, wound, resin-bonded fiber, stainless steel, and carbon block cartridges optimized for dirt-holding capacity and extended service life.

NeoLogic Solutions

• Melt-blown and pleated cartridges for standard industrial and high-purity applications.

EverWave Filtration Products

• Replacement filter cartridges for a range of industrial applications.

Applications

Industrial filter cartridges from CFS are used across industries where fine particle removal and product purity are critical, including:

• Food and Beverage
• Chemical Processing
• Pharmaceutical and Biotechnology
• Water and Wastewater Treatment
• RO Pre-Filtration
• Petroleum and Petrochemical
• Cosmetics and Personal Care
• Electronics and Semiconductor
• Paint, Coatings, and Inks
• Plating Solutions
• Metal Working Fluids

Not sure which cartridge is right for your application? Call (855) 236-0467 or submit a quote request for expert guidance, pricing, and availability.