"Microns" or Micron Ratings:
Now this is a term that carries some serious weight when selecting a fuel filter.
Seems that average Joe is more impressed by the smaller the number, than the
method used to measure or give the filter this "rating', the quality and type
of media used within the filter, and the capacity of the fuel filter( dirt/water
holding capacity).
Hmmm, rated 60 GPH with a 2 mic element-sounds way overkill to me considering
my engine only has 300 HP and burns 16 GPH at WOT. This is where Joe has missed
the big picture.
The "micron rating" of fuel filters is a very simple way of allowing someone
to select just one of the requirements for filtration. Our experience with
marine fuel systems has proven to us that the nominal micron rating is not
the best way of choosing correct filtration. Micron rating should only be used
to categorize the media since the most fuel filter ratings were developed based
on single-pass efficiency tests using uniform spherical particles as a system
contaminant. In real life, diesel fuel contains contaminants of various sizes
ranging from sub micron to 100's of microns in size.
Keep this very important point in mind when you only think "micron rating"
when choosing a filter - NEVER will you find a fuel filter with a rating of
10 microns, 2 microns, etc., that will stop 100% of the particles larger that
this nominal rating. NEVER... What you will find with a quality filter is:
1) Beta Ratio micron rating
2) Fuel flow vs. pressure drop rating when clean
3) Dirt holding capacity vs fuel flow-pressure drop
4) "Free" and "Emulsified" water separation ratings
5) Ratings / specifications from SAE, ISO and other world recognized organizations
6) Other important parameters concerning collapse and pressure ratings, etc.,
that were developed in conjunction with a specific requirement from an engine
manufacturer.
Keep in mind that Cummins, specifically, does not recognize micron ratings
as significant and specifically recommends the use of "Beta ratio" in selecting
a filter to meet system requirements. I am certain many engine manufactures
are of the same as to their requirements.
More help follows if you want to get real serious about fuel filtrations basics:
A "NO BS" guide to filtration and what it all about - Trust me, no "gizmos"
here!! http://wfc2.xapnet.com/filtration_basics/index.php
FRAM ( those "auto guys") also makes it easy to understand some basics about
microns and "BETA" test methods http://www.fram.com/pdf/FluidFilterRating.pdf |
