VEM A21 Serie Instructions De Montage, D'utilisation Et D'entretien page 23

Additional Installation, Operating and Maintenance Instructions (Translation)
If the condensate drain holes are closed with a plug, the condensate water must be drained frequently by hand.
7. Bearings
VEM motors are equipped with anti-friction bearings from respected manufacturers. The rated bearing lifetime is at
least 20,000 h with the exploitation of the maximum permissible load. The rated bearing lifetime for motors installed
in a horizontal position without additional axial loading is 40,000 h in the case of coupling service.
The versions
fixed bearing at N-end
without fixed bearing (floating bearing arrangement)
permanent lubrication
lubrication device
heavy bearing on D-end (for increased lateral forces)
and the
figures of bearing arrangement
disk spring or wave washer types
V-ring types
can be taken from the overviews of the bearing arrangements. The respective flat grease nipples are contained in
the tables of the design drawings. Motors in the normal versions with two deep groove ball bearings have preload-
ed bearings. Versions with cylindrical roller bearings on the D-end (heavy bearing arrangement VL) are excepted
from the preloading.
The most important prerequisite for achieving the normal bearing lifetime is correct lubrication, i.e. the use
of the right kind of grease according to the application, the filling with the correct amount of grease and
the maintenance of the subsequent lubrication periods.
The frame sizes 56 to 160 are equipped with life-lubricated bearings. These bearings are to be changed promptly in
accordance with the usable grease life. In the case of motors from size 180, the bearings must be lubricated
promptly in accordance with the usable grease life to keep the nominal bearing lifetime. Under normal operating
conditions, the lubrication filling will allow 10,000 operating hours for the 2-pole version and 20,000 operating hours
for the 4-pole version without lubrication. Under normal service conditions, for version with lubrication device, 2,000
or 4,000 operational hours will apply.
Design of the motor
Design series A2.., A4..
Design series ARB, ARC
Customer request
After approx. 5 re-greasings this old grease should be removed, e.g. as part of inspection work.
The final information about bearing size, grease type and lubrication periods must be taken from the
nameplate.
Motors of design series ARB are equipped with lubrication device as standard. In addition to the given regular lubri-
cation periods they must be lubricated after each prolonged blockage. After extended storage the bearing grease
must be checked visually and exchanged when the grease has hardened or other irregular conditions are visible. If
the motors will only be put into operation 3 years or longer after delivery by the manufacturer, the bearing grease
must be changed in any case. Motors with closed or sealed bearings must be changed after a storage period of 4
years by new ones from the same type.
3.2 Use of cylindrical roller bearings
By using cylindrical roller bearings ("heavy bearing arrangement" VL), relatively high radial forces or masses can be
taken up at the motor shaft end. Examples: belt drives, pinions or heavy couplings. The minimum radial force at the
shaft end must amount to a quarter of the permissible radial force. Account must be taken of the permissible shaft
end loading. These values can be taken from catalogue.
Low-voltage asynchronous motors, three-phase roller table motors with squirrel-cage rotor for
mains and inverter operation (EM/03-188 D/0214)
or from the below mentioned tables.
Grease type Name acc. to
Asonic GHY 72
Berutox FH 28 KN
Only after consultation with design department of VEM
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Temperature
DIN 51825 range in °C
KE2/3R-40 -40 bis +180
KHC1R-30 -30 bis +180
English