28
ROSSI
GEARMOTORS
UT.D 123 rev. 3
6 - Lubrication
6.1 - General
Gear reducers and gearmotors must be lubricated with polyglycol or
polyalphaolephines based synthetic oil depending on the series (s. lubri-
cation table at ch. 6.2)
They are supplied FlLLED WlTH OlL or WlTHOUT OIL depending on type
and size (see lubrication table at ch. 6.2). When supplying WITHOUT OIL,
the filling up to specified level (normally stated by means of transparent
level plug) is Buyer’s responsibility (see ch. 20 or SPT scheme attached)
and has to be carried out with gear reducer at rest.
With transparent level plug refer to its centre line when filling with oil.
Every gear reducer has a
lubrication plate.
Concerning lubricant type, how supplied status of gear reducers, plugs,
filling instructions, oil-change interval, etc. see lubrication table at ch. 6.2.
Be sure that for gear reducers and gearmotors size
100,
the filler plug is metal type provided with filter and valve (see
following picture).
Attention!
When these gear reducers are supplied with oil
(special design) the
filler plug is supplied loose
and is to be mounted
in the correct position (s. ch. 20 or SPT scheme attached) in place of the
fitted plug.
When gear reducer or gearmotor is
provided with a
plug for flowing over
level
(red colour) fill after unscrewing
a.m. plug in order to check the obtai-
ned level by oil outlet.
When gear reducer or gearmotor is
provided with a
level plug with rod
,
fill with oil up to specified level on rod.
When gear reducer or gearmotor is
supplied with a level plug (size
100),
the necessary lubricant quantity is that
which reaches a.m. Ievel in center line of plug (gear reducer at rest) and
not the approximate quantity given on the catalogue.
Usually bearings are automatically and continuously lubricated (bathed,
splashed, through pipes or by a pump) utilizing the main gear reducer lubri-
cant. The same applies for backstop devices, when fitted to gear reducers.
In certain gear reducers in vertical mounting positions V5 and V6, and
right-angle shaft gear reducers in horizontal positions B3, B6 (though
not gearmotors in this case, for which the above indications hold good)
upper bearings are independently lubricated with a special grease «for
life», assuming pollution-free surroundings. The same applies for motor
bearings (except some cases in which relubrication device is adopted)
and backstop devices when fitted to motors.
Always be sure that the gear reducer is located as per the mounting
position ordered, which appears on the name plate (fig. 1, ch. 1).
Combined gear reducer units.
Lubrication remains independent, thus
data relative to each single gear reducer hold good.
6.3 - Lubrication of extruder support
(
parallel
and
right angle shafts
)
The lubrication
of
extruder support
is
separate
from the gear reducer, except:
– in presence of the independent cooling unit, if applied to lubricate
both
the gear reducer
and
the support.
The
separate lubrication
of extruder support sensibly improves the
reliability and real life of the axial bearing; the separation between gear
reducer and support is granted by a seal ring.
With separate lubrication, for the extruder support, use polyalphao-
lephines based synthetic oil (MOBIL SHC XMP 680, CASTROL Tribol
1510/680) with
ISO 680 cSt
viscosity grade.
With
common
lubrication
(in presence of independent cooling unit, if
applied to lubricate both the gear reducer and the support), lubricant ISO
viscosity grade must be according to the instructions given in ch. 6.2
«lubrication table» and oil must be polyalphaolephine based synthetic
type.
For the filling up of oil of extruder support, see the table below.
For the lubrication of gear reducer refer to ch. 6.2, lubrication table.
7 - Commissioning
7.1 - General
Carry out a general check, making particularly sure that the
gear reducer is filled with synthetic oil in the correct
quantity, with the proper viscosity and one of the
brands recommended in table 6.2
.
If an external lubricating system is present (forced lubrication,
cooling unit) oil is to be filled to the correct level with the external
system full of oil.
Be sure that the
safety and control devices assembled
on the gear reducer
and requiring electric power supply
at user’s care
are active and running
. Be sure that the
independent cooling unit with coil
, if present,
is wor-
king during the gear reducer running
(see 5.5).
Where star-delta starting is being used, input voltage must match
the motor lower voltage (
connection).
For asynchronous three-phase motor, if the direction of rotation is
not as desired, invert two phases at the terminals.
Before running gear reducers fitted with
backstop device
, make
sure that the
direction of rotation in machine, gear reducer and
motor all correspond correctly.
Attention!
One or more startings in the false direction,
even if short, could irremediably damage the backstop
device, the coupling seats and/or the electric motor.
A
running-in
period with gear reducer running at 50% of rated tor-
que is suggested as follows:
– of approx. 400
1 600 h for gear reducers with worm gear pairs
in order to reach maximum efficiency;
– of approx. 200
400 h for gear reducers with bevel and/or
cylindrical gear pairs in order to reach the best possible running
conditions.
The temperature of both gear reducer and lubricant may well rise
beyond normal values during running-in, but lower than the maxi-
mum value stated on name plate. After the running-in period it may
be necessary to verify the gear reducer fixing bolt tightening.
During the first running hours it is possible to have a slight seepage
of grease from the seal rings, which will not affect the good running.
Note: worm gear reducer efficiency is lower in the
first running
hours
(about 50) and at every cold starting (efficiency will be better
with oil temperature increasing).
At first commissioning do all checks listed in table 14.
Repeat checks after 24 h and after one week for the
machines of category 2.
Check that the unit is not faulty (broken bearings, keys, shafts, etc.)
or shows signs of incipient malfunction (e.g. increased running
noise/vibration, etc.).
7.2 - Measurement of surface temperature
Measure by a thermometer the surface temperature of gear reducer
close to the high speed shaft (gear reducer) or at the coupling sur-
face between motor and gear reducer (gearmotors) in the position
which is most protected from air circulation.
When commissioning
this temperature is to be kept under con-
trol
and the max value is to be noted; the values are to be periodi-
cally checked (according to table 15) and compared with those which
were previously noted in order to verify if there is any increase; if
a signifiicant increase (
≈
10%) occurs, something is not working
properly and the machine must be stopped: consult ROSSI MOTO-
RIDUTTORI.
Attention!
Measure the difference in temperature (
T) compared to
ambient temperature at the same operating conditions.
Note
: the max surface temperature is reached after approx
1÷4
h
running on full load (the heating time is proportional to gear reducer
size). The difference in temperature shall not exceed ambient tempe-
rature by more than
45 K.
U
T.C
764
Filler plug
Plug for flowing
over level
Gear reducer
Lubrication of extruder support
size
Separate lubrication
1)
Common lubrication
2)
125 ... 451
Filling up
Filling up
to the level (of support) to the level (of gear red.)
1) Support with metal filter plug with filter and valve, level and drain plug.
2) The level is metal only in the gear reducer casing.
