| Symbol | ec |
|---|---|
| Unit | - |
| Attribute-ID | beiwertec |
| Numeric ID | 462 |
| Value Type | PMDouble |
The contamination quotient ec (also impurity coefficient) takes into account the reduction to the bearing life due to contaminants in the lubricant.
Foreign particles in the lubricant lead to plastic deformations on the bearing raceway. This causes excess stresses on these positions, resulting in a reduction of the bearing life.
Contamination quotient ec acc. to DIN ISO 281
| Contamination Coefficient | eC | |
| dpw < 100 mm |
dpw ≥ 100 mm |
|
| Extremely high cleanliness Particle size in the magnitude of the lubricating film thickness; laboratory conditions |
1 | 1 |
| High cleanliness Fine filtration of the oil supply; sealed, greased bearings |
0.8 - 0.6 | 0.9 - 0.8 |
| Normal cleanliness Oil filtered through a fine filter; greased bearings with sealing shields |
0.6 - 0.5 | 0.8 - 0.6 |
| Light contamination Light contamination of the lubricant |
0.5 - 0.3 | 0.6 - 0.4 |
| Heavy contamination Bearing area heavily contaminated; inadequate sealing |
0.1 - 0.0 | 0.1 - 0.0 |
| Very heavy contamination | 0.0 | 0.0 |
For additional information regarding calculation of the contamination quotient see DIN/ISO 281 (2010) p. 32 ff.