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Particle Contamination – ISO And NAS Cleanliness Codes

Oil cleanliness is critical to the reliability of your machinery. As technology advances, the demands placed on a lubricant are ever-increasing: pressures and temperatures are higher, reservoir sizes are smaller and component tolerances are tighter.

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
(ACHIEVABLE) 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
-

Understanding Oil Cleanliness

100-times magnified, 1 scale mark = 10μm

NAS Class 3

NAS Class 8

NAS Class 12

CARDEV Systems

Products that can achieve results that are

“Cleaner Than New”

ByPass Filtration Systems

Permanently installed bypass filtration using the flow and pressure of the system that is being filtered. All CARDEV bypass filtration is covered by our lifetime warranty*

Mobile Offline Filtration Systems

Mobile or permanently installed offline filtration systems that work independently of the system being filtered, using integrated pumps to provide pressure and flow.