New Cosmos Electric SDM-72, Instruction Manual

Page: 19 / 24

- 17 -
2) Correlation between the Abrasion of the Bearing and Steel Dust Concentration in the
Grease.
Table 2 shows the inspection results of correlation between the abrasion of the bearing
and steel dust concentration by disassembling and inspecting the bearing of various
rotating machinery such as motors, pumps and blowers.
Table 2 Correlation between the Abrasion of the Bearing and Steel Dust
concentration in the Grease
Fe concentration %Wt Number of bearing and status of abrasion
0.3 – 1.0
◆◆◆
0.1 – 0.3
●●▲▲▲▲
0.05 – 0.1
●●●●●
0.03 – 0.05
○○
0.01 – 0.03
○○○○○○○○○
0 – 0.01
○○○○○○○○○○○
Table number of bearings 36 pieces
◆
= Large damage (continuous flaking of inner and outer rings)
▲
= Medium damage (partial flaking of inner and outer rings)
●
= Slight damage (slight flaking, discolored abrasion of inner and outer rings)
○
= No abnormality
3) Criterion
The following table is an example of the criterion.
This criterion is relatively strict in order to carry out appropriate corrective
lubrication improvements, to detect the abnormal trend at an early stage.
Table 3 Criterion of the Steel Dust Concentration in the Oil
Criterion (ppm)
Countermeasure
Large sized
machine
Small sized
machine
Normal Less than 30 Less than 100 Management of steel dust contents
in the oil at normal cycle
Precaution 30- 100 100- 300
Repeat lubrication and re-measure
the steel dust concentration 1
month later.
Irregular More than 100 More than 300
Countermeasure for improvement
of lubrication, precision diagnosis
at short cycle management.
−17−
- 17 -
2) Correlation between the Abrasion of the Bearing and Steel Dust Concentration in the
Grease.
Table 2 shows the inspection results of correlation between the abrasion of the bearing
and steel dust concentration by disassembling and inspecting the bearing of various
rotating machinery such as motors, pumps and blowers.
Table 2 Correlation between the Abrasion of the Bearing and Steel Dust
concentration in the Grease
Fe concentration %Wt Number of bearing and status of abrasion
0.3 – 1.0
◆◆◆
0.1 – 0.3
●●▲▲▲▲
0.05 – 0.1
●●●●●
0.03 – 0.05
○○
0.01 – 0.03
○○○○○○○○○
0 – 0.01
○○○○○○○○○○○
Table number of bearings 36 pieces
◆
= Large damage (continuous flaking of inner and outer rings)
▲
= Medium damage (partial flaking of inner and outer rings)
●
= Slight damage (slight flaking, discolored abrasion of inner and outer rings)
○
= No abnormality
3) Criterion
The following table is an example of the criterion.
This criterion is relatively strict in order to carry out appropriate corrective
lubrication improvements, to detect the abnormal trend at an early stage.
Table 3 Criterion of the Steel Dust Concentration in the Grease
Criterion Countermeasure
Normal value Smaller than 0.05%
Management of steel dust contents
in the grease at normal cycle
Precaution
value
0.05 – 0.1%
Repeat grease lubrication and
remeasure the steel dust
concentration 1 month later.
Irregular
value
Greater than 0.1%
Countermeasure for improvement of
lubrication, precision diagnosis at
short cycle management.