Guide to Industrial Liquid Filter Cartridges

For instance, polyester (PE) filter cartridges offer a wider range of chemical compatibility compared to polypropylene (PP) filters, but PP filter cartridges work better for oil filtration applications. Additional factors you might need to determine about the material you wish to filter include:

Once we have a complete understanding of what you need to filter, we can direct you to the best style and material industrial filter cartridge for your application.

All filter cartridges have a micron (µm) rating and efficiency to ensure they will provide adequate liquid filtration. A micron is a unit of measurement equivalent to one millionth of a meter. We sell industrial filter cartridges with micron ratings from less than 1 micron up to 200 microns. How big is a micron exactly? Well, just for reference the average human hair is 90 microns and a white blood cell is 25 microns!

Industrial filter cartridges also have varying levels of efficiency. Nominal filtration means that the filter cartridge can trap particle sizes down to the listed micron rating. Nominal filtration cartridges may only have an efficiency of 75% of sediment capture at a specific micron rating. If you need more thorough liquid filtration, absolute rated filter cartridges filter to a higher degree of accuracy with efficiencies often close to or above 99% at their listed micron rating. Many filtration systems will use nominal filters earlier in the filtration process with absolute filtration at the end to ensure no contaminants are missed.

Gaskets

The gasket is a ring of rubber or similar material that seals the filter cartridge and the housing to eliminate sediment bypass. Factors in finding the best gasket for your application include: chemical compatibility, temperature and required service life. The Cary Company sells a range of gasket materials.

• Buna N, or nitrile-butadiene, offers good resistance to oils such as vegetable oil, petroleum oil, mineral oil, etc. Buna N is one of the most commonly used sealing elastomers known for its sealing property. It is resistant to lubricants and petroleum-based fuels.
• Ethylene Propylene is a synthetic elastomer with excellent resistance to weathering, sun and ozone. There are multiple types of ethylene propylene including EPR and EPDM, a copolymer and terpolymer respectively. Common industry applications are pharmaceutical, food and beverage, drinking water, etc. Ethylene propylene offers good wear and compression set resistance.
• Viton is also known as fluoroelastomer or FKM, which is a fluorocarbon-based synthetic rubber. Viton gaskets have excellent permeation resistance and good resistance to oxygen, fuels and many organic solvents and chemicals. This gasket material does well in high temperatures but is not ideal in low temperature applications.
• Also known as polytetrafluoroethylene (PTFE), Teflon gaskets offer good wear resistance and have one of the lowest coefficients of friction against solids. Due to its excellent chemical resistance, it is commonly used in chemical processing as well as medical and food production industries.
• Neoprene O-Ring or Chloroprene (CR) is a multi-purposed elastomer. This gasket ring is suitable for use with oils and most chemicals. Neoprene O-ring has good resistance to the sun, ozone, fire, alcohol, ammonia and weather.
• Silicone gaskets offer excellent temperature resistance for both hot and cold applications. They can resist warping and maintain a tight seal for extended periods of time. These gaskets provide good resistance towards a range of chemicals, oils and solvents.

End Cap Options: SOE or DOE

Single open ended (SOE) cartridges have a side of the cartridge sealed to ensure filter bypass is impossible on one side of the cartridge. The seal is typically a polypropylene cap. SOE filters are often used in sanitary applications but are associated with a higher cost. Double open ended (DOE) cartridges do not have a seal on either side of the filter cartridge. This option tends to be more common of the two types as eliminating sediment bypass can still be accomplished by relying on the filter housing.

End Cap Configuration Types

Type 226 have double gaskets and locking fins to ensure the filter cartridge is properly installed into the cartridge housing as it must be twisted as it is installed. The double gasket will prevent containment bypass by sealing against the housing. Type 226 is often used in sanitary applications.

Type 222 are often used with single open end cartridge filters. Double gaskets will seal the filter against the cartridge filter housing to prevent bypass.

Double open end (DOE) gasket filters have openings on both ends of the filter cartridge. This end cap option features gaskets to aid in sealing the filter against the housing.

When used in a multi-cartridge filter housing, the fin end cap sits inside the top retaining plate. However, these end caps are also used in singe cartridge filter vessels as well.

Commonly referred to as flat end filter cartridges, the closed end cap is a flat disc with no opening that is attached to one side of a filter cartridge. This end cap seals one side of a double open end filter cartridge allowing it to function as a single open end cartridge.

The spring end cap will collapse with pressure allowing for easy installation into housings. Spring end caps are often used with string wound cartridges, but can be used with other types of filter cartridges.

Filter Cartridge Core Material

Not every filter cartridge has a core. Often used for low micron ratings, the filter cartridge core provides support and prevents cartridge collapse. An inner core is particularly useful for additional support in high pressure applications.

Common materials for the inner core of filter cartridges include polypropylene, tinned steel, type 304 or 316 stainless steel and even glass. The inner core material is dependent on filtration temperature, chemical compatibility and application type.

Bag filters filter by capturing debris when fluid flows through small pores in the felt or mesh filtration media. The micron rating depends on the size of the openings in the media.

There is a wide range of filter bags and filter cartridges, each with their own dirt loading capacity, recommended flow rate, etc.

Filter Bags:

• Economic
• Wide range of filtration medias
• Less solid waste products in smaller volume applications
• Space-efficient for storage
• Can filter large micron sizes (We have liquid filter bags with ratings from 1 micron up to 1500 micron!)

Filter Cartridges:

• Pleated filters offer increased surface area as compared to filter bags
• Tend to have a longer service life
• Ideal for absolute filtration down to small micron ratings
• Provide surface or depth filtration

Feel like you are ready to shop our industrial filtration selection? Check out our liquid filter cartridges or filter bags. Still need more information? We have additional resources below!