Code ISO 4406 | Number of Particles/100ml | NAS 1638 | |||
---|---|---|---|---|---|
>4μm | >6μm | >14μm | |||
23/21/18 22/20/18 22/20/17 |
8,000,000 4,000,000 4,000,000 |
2,000,000 1,000,000 1,000,000 |
250,000 250,000 130,000 |
12 - 11 |
Very Contaminated - Breakdowns Inescapable |
22/20/16 21/19/16 20/18/15 |
4,000,000 2,000,000 1,000,000 |
1,000,000 500,000 250,000 |
64,000 64,000 32,000 |
- 10 9 |
|
19/17/14 18/16/13 |
500,000 250,000 |
130,000 64,000 |
16,000 8,000 |
8 7 |
Minimum required cleanliness class for high pressure - servo valve hydraulic systems, new/fresh oil DIN51524 |
17/15/12 16/14/12 |
130,000 64,000 |
32,000 16,000 |
4,000 4,000 |
6 - |
|
16/14/11 15/13/10 14/12/9 13/11/8 |
64,000 32,000 16,000 8,000 |
6,000 8,000 4,000 2,000 |
2,000 1,000 500 250 |
5 4 3 2 |
(ACHIEVEABLE) Results After CARDEV Microfiltration |
12/10/8 12/10/7 12/10/6 |
4,000 4,000 4,000 |
1,000 1,000 1,000 |
250 130 64 |
- 1 - |
100-times magnified, 1 scale mark = 10μm
NAS Class 3

NAS Class 8

NAS Class 12
