Bosch Rexroth IndraDyn S - MKE Project Planning Manual

Project Planning Manual | Rexroth MKE Synchronous Motors Electric Drivesand Controls| Bosch Rexroth AG 89/131Operating Conditions and Application Notes●●a shift in the position of the axis if the driving pinions are not defined axiallyon the machine side,a thermally dependent component of the axial force if the driving pinionsare defined axially on the machine side. This causes the risk of exceedingthe maximum permissible axial force or of the play within the gears increasingto an impermissible degree.9.10.4 Bearing LifetimeIn such cases, you should therefore preferably use drive elementswith their own bearings which are connected to the motor shaft viaaxially compensating couplings.The bearing lifetime is an important criterion for the availability of MKE motors.When the lifetime is considered, the "mechanical lifetime" of bearing componentsand materials is differentiated from the "grease lifetime" of the bearinglubricant.If the MKE motors are operated within the limits specified for radial and axialloads, the nominal service life of the bearings is as follows:Mechanical service life of bearingsMechanical bearing lifetime with increasedradial forceL 10h = 30,000 operating hours(calculated according to ISO 281, ed. 12/1990)This applies to all MKE motors based on the following:●●●The permitted loads from the corresponding chapter "Technical Data" arenever exceeded.The motor is operated under the permitted conditions for use and in thepermitted ambient temperature range of 0 °C to +40 °C.Differing loads can have the following effects:●●●Premature failure of the bearing due to increased wear or mechanicaldamage.Reduction of the grease lifetime leads to premature failure of the bearing.Avoid exceeding the load limits.In other cases, the bearing lifetime is reduced as follows:L 10h Bearing lifetime (according to ISO 281, ed. 12/1990)F radial Determined permissible radial force in N (Newtons)F radial_ist Actually acting radial force in N (Newtons)Fig.9-20: Calculation of the bearing service life L10h if the permissible radial forceFradial is exceededUnder no circumstances may the actually acting radial force F radial_istbe higher than the maximum permissible radial force F radial_max.