Finding the cleanliness level required by a system
- Starting at the left hand column, select the most sensitive component used in the system.
- Move to the right to the column that describes the system pressure and conditions.
- Here you will find the recommended ISO class level, and recommended element micron rating.
| Low/Medium Pressure Under 2000 psi (moderate conditions) |
High Pressure 2000 to 2999 psi (low/medium with severe conditions¹) |
Very High Pressure 3000 psi and over (high pressure with severe conditions¹) |
||||
| ISO Target Levels |
Micron Ratings |
ISO Target Levels |
Micron Ratings |
ISO Target Levels |
Micron Ratings |
|
| Pumps | ||||||
| Fixed Gear or Fixed Vane | 20/18/15 | 20 | 19/17/14 | 10 | 18/16/13 | 5 |
| Fixed Piston | 19/17/14 | 10 | 18/16/13 | 5 | 17/15/12 | 3 |
| Variable Vane | 18/16/13 | 5 | 17/15/12 | 3 | N/A | N/A |
| Variable Piston | 18/16/13 | 5 | 17/15/12 | 3 | 16/14/11 | 3² |
| Valves | ||||||
| Check Valve | 20/18/15 | 20 | 20/18/15 | 20 | 19/17/14 | 10 |
| Directional (Solenoid) | 20/18/15 | 20 | 19/17/14 | 10 | 18/16/13 | 5 |
| Standard Flow Control | 20/18/15 | 20 | 19/17/14 | 10 | 18/16/13 | 5 |
| Cartridge Valve | 19/17/14 | 10 | 18/16/13 | 5 | 17/15/12 | 3 |
| Proportional Valve | 17/15/12 | 3 | 17/15/12 | 3 | 16/14/11 | 3² |
| Servo Valve | 16/14/11 | 3² | 16/14/11 | 3² | 15/13/10 | 3² |
| Actuators | ||||||
| Cylinders, Vane Motors, Gear Motors | 20/18/15 | 20 | 19/17/14 | 10 | 18/16/13 | 5 |
| Piston Motors, Swash Plate Motors | 19/17/14 | 10 | 18/16/13 | 5 | 17/15/12 | 3 |
| Hydrostatic Drives | 16/15/12 | 3 | 16/14/11 | 3² | 15/13/10 | 3² |
| Test Stands | 15/13/10 | 3² | 15/13/10 | 3² | 15/13/10 | 3² |
| Bearings | ||||||
| Journal Bearings | 17/15/12 | 3 | N/A | N/A | N/A | N/A |
| Industrial Gearboxes | 17/15/12 | 3 | N/A | N/A | N/A | N/A |
| Ball Bearings | 15/13/10 | 3² | N/A | N/A | N/A | N/A |
| Roller Bearings | 16/14/11 | 3² | N/A | N/A | N/A | N/A |
¹ Severe conditions may include high flow surges, pressure spikes, frequent cold starts, extremely heavy duty use, or the presence of water
² Two or more system filters of the recommended rating may be required to achieve and maintain the desired Target Cleanliness Level.