VARISCO JB Serie Instrucciones Para Su Utilizacion Y Mantenimiento página 19

ISTRUCTIONS FOR THE USE AND MAINTENANCE -
- Unscrew the nuts (52) and remove the pump casing, taking care not to damage the
casing gasket (43)
- Block the impeller (03) and remove the self-locking impeller nut (33)
- Remove the impeller (03)
- Remove the head (19). The rotating part of the seal (40) mounted on the shaft sleeve (31)
will slide off the shaft together with the head
- Remove the stationary seat (39) and its gasket (38) from the head
- Remove the lip seal (41)
- Wash the head with solvent to remove any residue of grease and clean the seats of the
stationary seal and lip seal thoroughly
- Mount a new lip seal in the head. To facilitate assembly, smear a little oil on the seat and
on the outer surface of the lip seal.
- Mount the stationary portion of the seal (39) together with its gasket (38). To facilitate this
operation, wet the seat on the head and the gasket with methylated spirits. If necessary,
use a wooden plunger or similar to push the stationary seal (39) into its seat.
- Reassemble the head taking care not to touch the shaft with the stationary seal
seat. If this is ceramic, it could easily break or chip.
- Tighten the head screws (45) and nuts (45.1).
- Smear the gasket of the rotating seal seat (40) and the shaft sleeve (31) with oil and slip
the seal on to one end of the shaft sleeve.
- Slip the sleeve and seal on to the shaft and push to overcome the slight resistance offered
by the lip seal.
Take care that the seal does not slip off the shaft sleeve.
- Mount the seal support ring (25.1). Push this forward until it is possible to reassemble
the impeller key (60).
- Reassemble the impeller (03), the impeller washer (66) and tighten the impeller nut (33).
- Check the exact position of the impeller with respect to the wear plate as indicated in paragraph 12.6.
- Reassemble the casing gasket (43) after smearing both sides with grease.
- Reassemble the casing and tighten the nuts, checking that the impeller is free to rotate.
- Fill with grease the seal lubrication chamber (see paragraph 11.1.1).
12.6 Positioning of the impeller with respect to the wear plate(s)
- In all models, the distance between the top of the impeller blades
and the surface of the wear plate must be between 0,3 - 0,6 mm
(fig. 23). For the 12" model, the distance between the impeller
and the front and rear wear plates must be between 0,6 - 1 mm
(fig. 26).
- To achieve this, dimensions A and B in figs. 21, 22, 24, 25 must
be nearly as possible equal. To this end, use the shims (25.2)
(fig. 19) supplied with spare mechanical seals. These shims are
used to move the impeller further forward if it is too far from the
front wear plate or too near the rear wear plate (where forseen).
The shims should be mounted between the seal support ring
(25.1) (fig. 19) and the impeller. Further adjustments can be car-
ried out using casing gaskets and rear wear plate gaskets (where
forseen). The presence of the casing gasket (43) (fig. 10) 0,5 mm
thick then creates the correct distance (fig. 23).
12.7 Maintenance of the bearings (fig. 18)
The pump is supplied with the bearings already greased and does
not require maintenance for the first 500 hours of operation.
The bearings in the bearing housing must be lubricated appro-
priately, avoiding the use of too much grease which can cause
overheating and, as a result, damage to the bearings. NOTE:
consult ANNEX 1 on page 23 for the JD monobloc versions.
12.8 Replacing the bearings
- Empty the pump casing (see par. 7).
Attention: residual liquid may be found in the pump casing, head
and suction line. Take the necessary precautions if the liquid is
hazardous (inflammable, corrosive, poisonous, infected).
- Remove the casing, the head and the mechanical seal
- Remove the flexible coupling hub and the shaft key
- Remove the outer bearing cover (08)
- Extract the shaft from the coupling side
- Extract the bearings using a bearing extractor
- To reassemble, proceed in reverse order.
12.9 Endothermic motor maintenance
Maintenance must be carried out when the machine is not
operating.
For maintenance operations refer to the use and maintenance
manual of the engine supplied with the present manual.
JB / JD
fig. 21
impeller
fig. 23
wear
plate
fig. 25
fig. 19
fig. 20
fig. 22
fig. 24
wear
plate
fig. 26
impeller
19