SKF TKGT 1, Instructions For Use Manual

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37 SKF TKGT 1
4.4 Contamination
Application conditions:
• Wind turbines main shaft bearing.
• Large size Spherical roller bearing.
• High load, low speed, standing still conditions.
• 2 samples (1 & 2) taken from two different wind turbine parks –
Sampled from housing.
Grease used in both applications (similar grease):
• Lithium/Mineral – NLGI 1.
Nature of analysis:

Shelf life/Quality

Routine control

Damage

Grease performance

Trend analysis

Change of grease

Contamination expected

Other reasons: ..........................................................
Testing
Sample First visual
inspection
(3.3) Consistency test
(3.4) Oil bleeding test
(3.5) Contamination
test (3.6)
Fresh unused Brown NLGI class:
1
DAvFresh :
40 mm
SFresh :
1177 mm 2
Sample:
Wind turbine
park 1 Brown, oily
NLGI class:
0.5
NLGI difference:
-0.5
DAvUsed :
40 mm
SUsed :
1177 mm
2
%Diff :
0
Very few and
small sized
particles
Sample:
Wind turbine
park 2 Darkening, oily
NLGI class:
000
NLGI difference:
-3
DAvUsed :
44.5 mm
SUsed :
1476 mm
2
%Diff :
+25
Many big
particles
Interpretation
Sample 1:
Sample 2:
- Sample in good condition.
- Severe grease softening.
Check for possible sources of oil contamination.
Check sealing and leakage.
X