Rolling Bearing Faults; Faults At The External Fan - Siemens SIMOTICS XP Operating Instructions Manual

8.6.4

Rolling bearing faults

Damage to rolling bearings can be difficult to detect in some cases. If in doubt, replace the
rolling bearing. Use other bearing designs only after consulting the manufacturer.
Table 8- 3 Rolling bearing faults
↓ Bearing overheats
↓ Bearing "whistles"
↓ Bearing "knocks"
Possible causes of faults
X High coupling pressure
X Belt tension too high
X Bearing contaminated
X High ambient temperature
X X Insufficient lubrication
X X Bearing canted
X X Insufficient bearing play
X Excessive bearing play
X X Bearing corroded
X Too much grease in bearing
X Wrong grease in the bearing
X Friction marks on raceway
X Brinelling or scoring
8.6.5

Faults at the external fan

The following table shows the possible causes of and remedial measures for faults on forced-
ventilated machines.
Table 8- 4 Cooling system faults
↓ High temperature rise with load
Possible causes of faults
X Wrong direction of rotation of the separately
driven fan
X Separately driven fan is not running
X Reduced air flow
1MB..5/6 shaft height 71 ... 355
Operating Instructions, 10/2021, A5E41926185A
Remedial measures
Align the machine more accurately.
Reduce the drive belt tension.
Clean or replace the bearing. Check the seals.
Use a suitable high-temperature grease.
Grease the bearings as instructed.
Contact the service center.
Contact the service center.
Contact the service center.
Replace the bearing. Check the seals.
Remove surplus grease.
Use the correct grease.
Replace the bearing.
Replace the bearing. Avoid any vibration at standstill
Remedial measures
Check the electrical connections to the separately driven fan.
Check the separately driven fan and its connections.
Check the air ducts; clean the machine.
Operation
8.6 faults
101