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NT 1003-A00 09 18 AZ O e
8. DRILLED PISTON PUMP
Drilling the piston permits the circulation of the product behind
the piston and therefore avoids any "dead" zone.
It also helps to avoid any over-pressure problems related to
the expansion of hot products.
The piston is drilled with 2 holes (A) though only one remains
open,
always on the inlet side
(the other is closed in the fac-
tory).
If the rotation direction of the pump requires the standard
assembly to be changed, open the plugged hole by removing
the screw and use the screw to close the other hole on the
discharge side, with removable thread locker (typ Loctite
®
243*).
The screw must be recessed from cylinder rubbing surface
(1 mm).
* Loctite
®
is a registered trademark.
Dimension
and position of holes
Ø A
C ± 0.2
B ± 0.2
M4
2,3
25,5
7. MAINTENANCE
7.1 Greasing
Except for special cases, the MOUVEX pump only requi-
res lubrication of the shaft inlet bearing.
Use a grease for good quality ball bearings.
Lubrication must be done every 1,000 hours of operation
or at least once a year.
The quantity of grease to be added must not exceed 5 cm
3
.
For pumps operating at high temperatures (in principle
from 100°C upwards) use a grease with a high drop
point.
If the pump is equipped with a Stofer oiler, and when the
type of product requires it, the pump must be greased
before each start-up, after each shutdown and every 3
to 4 hours of continuous operation.
Preference should be given to lubricants insoluble in the
product pumped and, in the case of hot products, lubri-
cants that maintain good viscosity at the operating tem-
perature.
The other elements of the pump unit (motor, reduction
gear) should be maintained in conformity with their spe-
cific technical instructions.
7.2 Checking of parts
The piston
301
and the cylinder
201
are active parts
(wearing parts). These parts must be replaced if the
thickness measurements are lower than the following
values :
- Piston (
301
) . . . . . . . 5 mm
- Cylinder (
201
) . . . . . .17 mm
301
201
