The Dynamic Filtration Efficiency (DFE) Test is Hy-Pro's standard for testing filter elements. Throughout this four-part series  (find parts two, three and four) we'll discuss what it is, why it matters and why elements engineered with this test in mind outperform others in real-life applications.

First, let's start with the basics.

Why are filters used? How are they rated?

All hydraulic and lube systems have a critical contamination tolerance level that is often defined by -- but not limited to -- the most sensitive system component such as servo valves or high-speed journal bearings. Defining the ISO fluid cleanliness code upper limit is a function of component sensitivity, safety, system criticality and ultimately getting the most out of hydraulic and lube assets.

The Problem: Hydraulic Pump Failure 

Pumps are the heart of hydraulic systems. When the pump fails, the entire system is down until the pump is operational again. This poses a serious threat to any operation relying on hydraulic systems for productivity.

Recently, a hydraulic valve manufacturer was losing 25 pumps a year on their centralized hydraulic system at a cost of $2,440 each -- and that’s only the pump cost. When you account for maintenance resources, lost oil and lost production, each failure costs ~$25,320.

The Application

A hydraulic valve manufacturer required pristine fluid (< 14/12/9) to test flow across an 80-micron orifice on their test stand. Gross amounts of contamination in the fluid would skew the test results, invalidating any data collected.

The system held 100 l (26.4 gal ) of ISO VG 32 fluid with a flow rate of 25 lpm (6.6 gpm ).Through observing the manufacturer’s sampling practices, discussing fluid handling best practices and interpreting their lab reports, three independent problems were identified:

Do you have trouble translating your fluid analysis reports into useful information you can act upon? If you were to notice high levels of Ba on your report would you know what it is and where its likely coming from?

If you could use a hand we’ve got the perfect tool in our new Fluid Analysis Reference Guide. Within the chart below are contaminants found on fluid analysis test reports listed according to their chemical symbol (often how they'll be listed on the reports) and the various sources from which they are known to occur. 

Hopefully, this chart will be a handy reference for reading and analyzing your fluid analysis reports.