Donaldson Hydraulic Filters Catalog

TECHNICAL REFERENCE

Combining the ISO Rating and Filter Performance Ratings

While filter manufacturers publish beta ratings for filter media to describe efficiency performance levels, a direct connection between the beta rating scale and the ISO rating scale cannot be made. The solution is monitoring filter media performance at removing particles in the 4 m, 6 m, and 14 m ranges. Fluid analysis and field monitoring are the only ways to get these measurements. Combine data from several tests to form a range of performance. Remember, actual filter performance will vary between applications. Here’s how to determine which filter media will best protect your hydraulic components: plot any media performance range on the Application Guide to Donaldson Filter Media (page 158), then connect the dots to make a line. On the same graph, plot your component requirement. (Reference chart below for some popular components, or ask your supplier for the recommended ISO rating.) If the line of the media falls below the ISO line, or if the bottom line of the filtration range does not intersect the ISO line, the component will be protected.

Typical ISO Cleanliness Here are some typical ISO cleanliness recommendations from component manufacturers. (These are guidelines; always check the ratings specified by the manufacturer of your specific components.)

Pressure

<3000 PSI >3000 PSI 210 Bar >210 Bar

Pumps

--- ISO RATINGS ---

Fixed Gear Pump Fixed Vane Pump Fixed Piston Pump Variable Vane Pump Varibale Piston Pump Valves Directional (solenoid) Pressure (modulating) Flow Controls (standard)

19/17/15 19/17/14 18/16/14 18/16/14 17/15/13 20/18/15 19/17/14 19/17/14 20/18/15 20/18/15 18/16/14 18/16/13 18/16/13 16/14/11* 20/18/15 19/17/14 18/16/13 20/18/15 19/17/15

18/16/13 18/16/13 17/15/13 17/15/13 16/14/12 19/17/14 19/17/14 19/17/14 20/18/15 19/17/14 17/15/13 17/15/12* 17/15/12* 15/13/10* 20/18/15 18/16/13 17/15/12 19/17/14 18/16/13

Check Valves

Cartridge Valves

Load-sensing Directional Valves Proportional Pressure Controls Proportional Cartridge Valves

Micron Sizes of Familiar Particles

Servo Valves

Actuators Cylinders Vane Motors

Grain of table salt

100 m 80 m 40 m 25 m 10 m

Human hair

Lower limit of visibility

Axial Piston Motors

Gear Motors

White blood cell Talcum powder Red blood cell

Radial Piston Motors

8 m 2 m

* Requires precise sampling practices to verify cleanliness levels. Source: Vickers

Bacteria

Silt

<5 m

40 μm

80 μm

25 μm

10 μm

100 μm

2 μm

28 • Hydraulic Filters & Accessories