76
As a policy of continual improvement, STAUFF reserves the right to alter the specification without prior notice.
201.031
Date of Issue: 06 November 2018
Hence there may be a possible source of conflicting information when comparing cleanliness levels
recommended from different sources.
The table gives a selection of maximum contamination levels that are typically issued by component
manufacturers. These relate to the use of the correct viscosity mineral fluid. An even cleaner level may
be needed if the operation is severe, such as high frequency fluctuations in loading, high temperature or
high failure risk.
11.8 Hydraulic System Target Cleanliness Levels
Where a hydraulic system user has been able to check cleanliness levels over a considerable period, the
acceptability, or otherwise, of those levels can be verified.
Thus if no failures have occurred, the average level measured may well be one which could be made a
bench mark. However, such a level may have to be modified if the conditions change, or if specific
contaminant-sensitive components are added to the system. The demand for greater reliability may also
necessitate an improved cleanliness level.
The level of acceptability depends on three features:
- The contamination sensitivity of the components
- The operational conditions of the system
- The required reliability and life expectancy
Contamination Codes
ISO4409:1999
Corresponding
Codes NAS1638
Recommended
Filtration
Degree
Typical Applications
4μm(c)
6μm(c)
14μm(c)
βx200
14
12
9
3
3
High precision and
laboratory servo-
systems
17
15
11
6
3-6
Robotic and servo
systems
18
16
13
7
10-12
Very sensitive
– high
reliability systems
20
18
14
9
12-15
Sensitive
– reliable
systems
21
19
16
10
15-25
General equipment of
limited reliability
23
21
18
12
25-40
Low pressure
equipment not in
continuous service
Содержание LPM-II-plus
Страница 1: ...Manual Particle Monitor LPM II plus...
