Coalescer/Separator Cartridges for Aviation Fuel

Qualified to EI 1581 5th Edition

Coalescer/Separator Cartridges Qualified to EI 5th Edition - #1923

The following products have been fully qualified to the EI 1581 5th Edition specification


The I-6xxC5 (TB), I-6xxMM, and I-6xxA4 Series coalescers (“xx” denotes nominal cartridge length) incorporate multi-layered pleated media designed to provide superior dirt holding capacity in the field, combined with 0.4 micron efficiency. The I-6xxC5 (TB) replaces both Velcon’s I-6xx85 (TB) and I-6xx87 (TB) cartridges. These cartridges are available in either threaded base or open-end configuration. For more information concerning coalescer dimensions and general specifications please refer to Velcon’s data sheet #1732.


The SO-6xxV5, SO-6xxPV5, and SO-6xxVA5 are Teflon® Coated Screen (TCS) cartridges. SO-6xxVSN, SO-6xxPVSN, and SO-6xxVASN are synthetic separator cartridges. To achieve optimum flow distribution all of these cartridges incorporate a variable hole pattern inner tube combined with a uniform hole pattern outer tube specifically designed for installation in vertical filter/separators. Please refer to Velcon’s data sheet #1521 for overall separator dimensions and general specifications.

Teflon® Coated

Screen Separators

Close-up of water being

repelled by separator


Velcon Filters, LLC. has tested and qualified a comprehensive range of products to meet the EI 1581 5th Edition Specification. For a complete listing of Velcon’s current qualification tests, please view the following web page:

The categories for this specification are:


This category replaces the previous class A, B, & C of EI 1581 Third Edition. Velcon’s new coalescer cartridges that meet Category C requirements are the I‑6xxC5 Series (“xx” denotes nominal cartridge length). These cartridges have been developed to provide
better water removal performance in surfactant-laden fuels, and improved filtration efficiency combined with longer life. Category ‘C’ cartridges can be used at any point in the fuel distribution system – from refineries to final fuelling of aircraft. All of Velcon’s TCS Separator Cartridges are qualified for Category C.


This category covers military fuels, such as JP8 (similar to Jet A but containing anti-icing and other additives). Velcon’s coalescer products for this category are the I-6xxMM Series cartridges. The separators for this category are currently TCS Separators SO-6xxV5, SO-6xxVA5, and SO-6xxPV5, as well as Synthetic Separators SO-6xxVSN, SO-6xxPVSN, and

Category M qualified cartridges also qualify for Category C.


This category is for military fuels such as JP8+100.
The ‘+100’ additive allows fuels to run at higher operating temperatures and reduces maintenance for high performance military jet engines. Velcon’s coalescer cartridges for the M100 Category are the I-6xxA4 Series. The TCS Separators for M100 are currently the SO-6xxCM and SO-6xxGS (three-stage).




The 5th Edition also allows operators to incorporate third stage filter cartridges with each category. Velcon has currently qualified the CDF®-2xx Series monitor (water absorbing) cartridges for Category C and the FOW-2xx Series filter cartridges for Category M100.

Another aspect of the EI 1581 5th Edition specification is the description of filter/separators as Type S (water and dirt), Type S-LW (for applications where low amounts of water are expected) and Type S-LD (for applications where low amounts of dirt are expected). Products qualified for Type S are also qualified for Types S-LD and Type S-LW.

To obtain your authorized Velcon EI 1581 5th Edition Similarity Data Report for existing vessels, please complete the Velcon Similarity Certificate Form, #1728 (formerly called the “Fast Fax” form).