![background image](http://html.mh-extra.com/html/abb/amd-rg-355/amd-rg-355_installation-operation-and-maintenance-instructions_3045307101.webp)
Instruction, operation and maintenance instructions
High voltage flameproof motors for explosive atmosphere
AMD Rg 355-400-450-500
Horizontal motors with sleeve bearings – Assembly and
disassembly instructions
Oil lubricated DIN-EF sleeve bearings
Issued by: MOLM
Sheet No.
3AAM101048 E
Rev. B 01.2023
Page 2 of 5
W
e r
eserve
a
ll
rig
ht
s i
n t
his
do
cument an
d in t
he
inf
orm
at
io
n
con
tai
n
e
d
the
rein.
R
epr
o
duct
ion
,
use of
di
sc
losu
re
t
o t
h
ird
par
tie
s
w
itho
ut
ex
pr
es
s aut
h
or
ity
is
st
ric
tly
for
bidd
en.
Important!
Explosion-proof motors should be serviced,
following the proper instructions, only by trained
and certified personnel, preferably under the
supervision of
Service organization.
Maintenance operations must comply with the
rules specified in the EN/IEC 60079-17 and
60079-19 Standards.
Machine disassembly
The following sequence of operations applies to the
usual maintenance jobs, that can be required during
the overhauls.
Disconnect all cables and leads for power supply,
instrumentation, monitoring equipment and
earthing. Drain oil from both bearings. If the
bearings have a separate flood-oil supply,
disconnect the oil feed and return lines.
Remove the N-end mounted fan cover, external
fan, temperature sensors and auxiliary devices, if
any.
Remove the machine holding-down bolts and any
dowel pins (if any), then uncouple the shaft.
Pull the coupling hub from the shaft extension
(see 3AAM101031). If the machine has a
coupling at each end, remove both.
Remove the bolts (1), which connect the flange of
the bearing housing top part (2) at the bearing
endshield (3).
Remove bolts (4) and cylindrical pins (5) at the
split of the bearing housing top part.
Remove the bolts (7), which connect the bearing
housing top part and detach the oil seal (8) and
cover (9) from the housing.
Carefully raise the bearing housing top part (2)
just enough for the housing joint to open evenly,
then swing it out of the bearing endshield (3) and
lift it off. Use the eyebolts on top of the bearing
housing top part (2) for lifting!
Remove both halves of the oil seals (8).
Dismantle the shaft oil seals (10) and (11). For
this purpose slightly pull up the relevant upper
halves and tilt until the garter spring (12) can be
unlatched.
Open the garter spring (12) by turning left on the
lock and carefully remove the lower half of the
seal.
Mark the assembly position of the bearing shell
top part (13) and take it off carefully.
Remove the bolts of the loose oil ring (14) and
carefully handle the two halves in a way not to
affect their true geometric shape.
Disconnect the thermometers
and
other
instruments, if any.
Raise the shaft (lifting point = middle of the shaft
extension) by only one or two tenth of a millimeter
just enough to relieve the bearing shell bottom
part (15).
Pay attention: the air gap between the flame
arrester (18) and the shaft is only few tenths
of millimeters!
Protect the shaft extensions before you attach the
lifting means to the shaft.
If necessary, extend the shaft by means of bolted
extensions. After raising the shaft, hold the shaft
in position with wooden blocks, so you can use
the crane for further work.
Repeat the operations on both sides.
The disassembly work described below must be
done at N.D.E. first!
Turn the bearing shell part (15) until it can be
removed. Lift it by using eyebolts in the threaded
holes at the bottom and remove.
Now dismantle the bottom half of the bearing
housing (6) and bolts (16). The bottom half
housing is centered and secured to the endshield
by two conical pins, that must be removed. Take
care of the correction thickness for axial and
radial centering of the bearings, of the following
types:
for axial centering (magnetic centering
between stator and rotor) some ring shaped
thickness can be inserted between the
bearing and the endshield.
for radial centering some brass thickness
can be glued upon the fitting of the bearing
provided on the endshield.
Take good note of these centering thickness, and
if the removal is necessary mark them in a way
that permits their exact reposition on site during
the reassembling of the machine.
Release the labyrinth flame arrester (18) by
loosing the relevant screws. REMARK: Between
the flame seal and its fitting on the endshield
some annular thicknesses can be inserted, to
obtain the axial centering of the flame seal
against the labyrinth ferrule provided on the shaft.