Filter Cartridge End Caps
There are a variety of different “end cap” configurations which have developed over the years and it is important to understand their advantages and disadvantages and where and when they should be used.
Double Open End
The simple DOE is a standard for many plastic housings and relies upon the pressure of the closed housing to force a seal on the top and bottom of the filter cartridge. On some cartridges the knife edge seal will simply push into the cartridge media whilst other cartridges use a seal material, typically Silicone or EPDM. It may be considered the least secure form of seal and is sufficient for many applications.
Generally used for industrial applications the Code 3 utilises an end cap with 2 BS222 O rings with a flat top.The end cap is a simple push fit into a retainer at the base of the filter housing .Some housings have cartridges kept in place by a simple retaining plate at the top of the housing. This type is very common and generally universally available. It is a good style for use with Carbon or AlcaFil N or B cartridges
An industry standard for Pharmaceutical,Chemical and Beverage applications the Code 7 has an end cap with 2 BS226 O rings and a locking lug and a spear top. The cartridges are inserted and then turned to complete a secure seal with cartridges then held in place by a top retaining plate. A common and universal fitting. The best style for AlcaMem, AlcaPleat and AlcaFil B cartridges.
Falling in between a C3 and C7 the Code 8 is generally considered for industrial or semi critical applications. It uses an end cap with 2 BS222 O rings with a spear top. The end cap is a simple push fit into a retainer at the base of the filter housing with the cartridges being held in place by a top retaining plate. May be considered for Carbon,AlcaFil B or AlcaPleat cartridges.
Using and end cap with 2 BS226 O rings and a locking lug with a flat top this configuration is often used for gas applications.
Uses an end cap with 2 BS224 O rings and a spear top. This may not be considered as a universal fitting and cartridges are not readily available from sources other than the original supplier thereby limiting choice. Alchemy can supply a housing adaptor for this style if required.
A BS213 internal fitting designed for plastic housings.