Understanding Cartridge Filter End-Cap Types and How to Choose the Right One for Your Filtration System

In cartridge-based filtration systems, the end-cap connection plays a critical role in ensuring compatibility, sealing integrity, operational safety, and overall filtration performance. However, this detail is often overlooked—especially by new users. Selecting the wrong end-cap can lead to bypass leakage, reduced filtration efficiency, or complications during maintenance.

This article from Filterfine Vietnam provides a clear overview of the most common end-cap types, how to select the appropriate option, and recommended Entegris filter cartridges that match each application.

1. What Is a Cartridge Filter End-Cap?

The end-cap is the connection interface at both ends of a filter cartridge. It ensures proper installation inside a filter housing. The type of end-cap determines:

• Seal integrity
• Bypass-free performance
• Compatibility with pressure or vacuum systems
• Ease of cartridge replacement
• Compliance with international housing standards

Common end-cap types include: Code 0 (222/Fin), Code 2 (222/Flat), Code 7 (226/Flat), Code F (Flat), and DOE (Double Open End).

2. Common Cartridge End-Cap Types

• Code 0 (222/Fin)

• 222 end with fin structure and an O-ring
• Excellent sealing and easy replacement
• Widely compatible with industrial and pharmaceutical housings

• Code 2 (222/Flat)

• 222 end combined with a flat sealing surface
• Provides better stability and a larger sealing area

• Code 7 (226/Flat)

• 226 end with anti-rotation locking design
• High pressure resistance
• Ideal for quick-change systems requiring secure and reliable sealing

• Code F (Flat)

• Standard flat-end design
• Suitable for a range of general-purpose housings
• Relies on flat flange and O-ring compression for sealing

• DOE (Double Open End)

• Open on both ends, no end-cap
• Used in basic housings or temporary applications

3. Why Choosing the Correct End-Cap Really Matters

✔ Ensures Absolute Sealing (No Bypass)

Incorrect end-caps allow unfiltered liquid to bypass the cartridge, causing contamination and product defects.

✔ Simplifies Maintenance

End-caps such as Code 7 enable fast installation and removal, saving downtime.

✔ Optimizes Pressure Performance

Proper end-cap selection improves mechanical strength, especially under high-pressure conditions.

✔ Guarantees Housing Compatibility

The cartridge and housing must match in standard and design to prevent misalignment, leakage, or improper installation.

4. Entegris Cartridge Filters with Multiple End-Cap Options

As the authorized distributor of Entegris in Vietnam, Filterfine Vietnam provides a wide range of Entegris filter cartridges equipped with all major end-cap types to suit diverse applications—semiconductor, pharmaceutical, food & beverage, ultrapure water, and industrial chemicals.

5. Benefits of Choosing the Right Entegris Cartridge End-Cap

• Stable and consistent filtration performance
• Zero bypass leakage
• Extended cartridge lifetime and reduced clogging
• Faster maintenance and compliance with GMP/ISO
• Broad compatibility across numerous filtration systems

6. Why Choose Filterfine Vietnam?

• Official Entegris distributor in Vietnam
• Engineering team with deep expertise in end-cap specifications, housings, and filtration system design
• Technical consultation tailored to pressure, flow rate, temperature, and O-ring material
• Support for custom-size or special-design cartridges
• Provision of datasheets, CO/CQ, and integrity test reports for GMP validation

7. Conclusion

The end-cap connection is a key factor that directly impacts sealing integrity, system efficiency, and overall operating cost. By selecting genuine Entegris filter cartridges together with professional technical guidance from Filterfine Vietnam, your facility will benefit from a stable, reliable, and internationally compliant filtration system.

👉 Contact Filterfine Vietnam today for expert guidance on choosing the right end-cap type (Code 0, Code 7, DOE, etc.) for your filtration application.