Installation, operation and maintenance instructions
High voltage flameproof motors for explosive atmosphere
AMD Rg 355-400-450-500
Horizontal motors with rolling bearings – Assembly and
disassembly instruction
Issued by: MOLM
Sheet No.
3AAM101047 E
Rev. B 01.2023
Page 4 of 4
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housing hole and two isolating washers. Extreme
care is to be taken when dismantling.
-
Check the surfaces of the flame-arresters to
ensure there are no incisions or signs of contact
with the shaft during rotation.
Note! Protect the bearings against dust and
moisture by wrapping them in protective waxed
or oiled paper, if they are to be reused.
It is not recommended to re-use the bearings
after dismantling.
Machine assembly
The motor can be reassembled following the
disassembly operations in reverse order.
Make sure that all the internal components
fastened with screws are well tightened and
provided with the relevant locking devices.
Check the flame-arresters before assembling the
internal surface is to be free of scores or signs of
rubbing with the shaft. Check the correct
roundness and cylindrical geometry before
assembling.
Warning:
The original inner diameter dimensions of
the flame arrester are not to be changed under any
circumstances!
If assembling new bearings, the type must be
exactly the same as indicated on the plate on the
motor. Before assembling the bearings, make
sure that the clamping surface on the shaft, the
bearing and the shield housing are perfectly clean
and without burrs. To assemble the bearings, it is
advised to heat them (with induction heater or oil
bath) to a temperature between 100°C and 120°C.
Never heat the bearings with a naked flame! For
an isolated, check that the isolating layer in the
shield housing hole and the isolating washers are
intact. Assemble the isolated bearing first, so as to
be able to check its isolation resistance before
assembling the second bearing.
All the surfaces of the flat and embedded joints,
machined with a reduced roughness (flame
arrester joints) are to be examined to ensure there
is no scoring or damage and are to be smeared
with a thin film of an appropriate silicon grease
(see the relevant drawings for further details)
before assembly, to prevent rust forming. The
spigoted joint between casing and shields has a
very small clearance, to ensure the centering of
the rotor to the stator, consequently in this zone a
molybdendisulphide grease is to be used (anti rust
type)when assembling, to avoid any seizing. Any
damaged flame arrester joints are to be restored
to the original shape, dimension and roughness as
indicated on the original drawing before being
reassembled.
When reassembling the terminal boxes (main
and auxiliary) carefully check the joining
surfaces between the boxes and their covers, to
ensure there are no scratches or damage.
Before closing and tightening the bolts, smear
the coupled surfaces with a slight film of silicon
grease.
Important!
If screws or bolts have to be replaced, it is
compulsory to use screws and bolts of the same
quality and mechanical strength as the original
components, as indicated on the motor plate.
