Three-phase squirrel cage induction motors in flameproof enclosure type ASA and E2-ASA
frame size 63 – 355
8.1
Dismounting of the terminal box
(see fig. 1 and 2)
dismount the terminal box cover (1) enabling thus the access to the
screws fixing the supply cable to the terminals (bushings). Use a proper wrench to
unscrew the hexagon socket head cap screws. To remove the terminal box cover
tap it alternatively with a wooden, plastic or rubber hammer avoiding to lock it.
using a hexagon wrench unscrew the presser (2) and take off the supply
cable from the terminal box
remove the terminal box (3) using an adequate device
unscrew the nuts (4) at the bottom of the terminals, loosing the wire
terminals
the bushings can be removed using a socket wrench after the terminal
box is dismounted
8.2
Dismounting of the fan
(see fig 1 and 2)
remove the fan cowl (6); in case of motors with regreasable bearings,
prior to removing the cowl, the lubricating devices (5) must be taken off
remove the safety ring (7)
using an adequate device remove the fan (8) from the shaft
8.3
Dismounting of the rotor
(see fig 1 and 2)
dismounting should be made observing the operation succession given in
fig. 1 and 2
using appropriate dismounting devices (mechanical presses with
threaded rods and central screw), the shields should be pulled-off from the
housing. When pulling the shields, the pressure should be applied gently,
evenly, to avoid the damaging of the contact surfaces forming flame-proof
joints or the bearings.
8.4 Dismounting of the bearings
Mechanical jaw pullers or other proper dismounting tools should be used to
remove the bearings from the shaft or from the shields
8.5
Re-mounting of the motor
It should be done in reverse order of the dismounting operations (see fig. 1
and 2)
Before mounting, the surfaces forming flameproof joints between stator-
shields, stator-terminal box, terminal box-terminal cover and the thread joints
of the cable entries, shall be protected with a thin layer of grease having the
technical parameters according to
Annex 4
or other similar grease.
