Considering EP additives
EP additives in the lubricant can extend bearing service life when, in accordance with ISO 281:2007, κ < 1 and the factor for the contamination level ηc ≥ 0,2. Under these conditions, a value of κ = 1 can be applied in the calculation of aSKF, if a proven lubricant with effective EP additives is used. In this case, the life modification factor has to be limited to aSKF ≤ 3, but should never be lower than aSKF for normal lubricants.
For the remaining range, the life modification factor aSKF can be determined using the actual κ of the application. In case of severe contamination, i.e. contamination factor ηc < 0,2, the possible benefit of an EP additive has to be proved by testing. Refer to the information about EP additives presented in Lubrication.