Outside-to-Inside Flow
Definition
A flow configuration in which liquid enters the outer surface of the element and exits through the core, using the full pleat area for filtration.
Outside-to-inside flow is the standard for high-flow pleated elements. Contaminant collects on the large outer pleat surface, maximizing dirt-holding capacity and keeping ΔP low over the service life.
This configuration also allows very high per-element flow rates, which is why it is used almost universally in 6" high-flow platforms.
Relevance for high-flow filtration
R+F elements replicate the OEM outside-to-inside design and end-cap sealing so replacement is a true drop-in.
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Related terms
A large-format filter element designed to process very high liquid flow rates through a single cartridge, reducing the number of elements, housing size, and change-out labor compared with standard cartridges.
Pleated Filter ElementA filter whose media is folded into pleats to pack a large surface area into a compact element, lowering pressure drop and extending life.
226 O-Ring InterfaceA common cartridge end-cap connection using dual 226-code O-rings with a locating fin or bayonet, sealing the element into the housing tube sheet.
End Cap (DOE / SOE)The molded or welded cap that seals each end of a filter element and defines how it interfaces with the housing.
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