Repairing Hydraulic Parts; Dismantling The Head-Valve Units; Reassembling The Head - Valve Units - Pratissoli KE Serie Manual De Reparación

Once the type and number of shims have been determined
using the table, check the following: assemble the shim pack
on the indicator side cover centring (Fig. 15), secure the cover
to the casing, following the procedure in par. 2.1.2, and tighten
the screws to their recommended torque.
Check that the shaft rotation stall torque is between 4 Nm and
6 Nm.
If this torque is correct, connect the con-rods to the bend
shaft and to the next stages. If it is not, redefine the shim pack,
repeating the operations.
2.2

REPAIRING HYDRAULIC PARTS

2.2.1

Dismantling the head-valve units

Operations are limited to inspection or replacement of valves,
if necessary.
Proceed as follows to extract valve units:
- Unscrew the 7 M10x25 valve cover fixing screws and
remove the covers (Fig. 16, Fig. 16/a).
- Remove the valve plugs by means of an extractor hammer
(code 26019400, Fig. 16).
- Remove the valve units using pliers (Fig. 16/a).
If the suction and outlet valve seats remain
stuck on the head (for example because of
incrustations due to prolonged lack of use of the
pump), proceed as follows:
- use the extractor hammer used for the valve
plugs (code 26019400 combined with the tool
code 27513700), as shown in Fig. 16/b.
Fig. 15
- Disassemble the suction and outlet valve units, screwing
a sufficiently long M8 screw in such a way as to be able to
reach the valve plate and extract the valve guide from the
valve seat (Fig. 17, pos. ).
Fig. 16
2.2.2 Reassembling the head – valve units
Do not invert the springs on the suction valve
units with those on the exhaust valve units as in
some models these are not interchangeable.
Pay particular attention to the conditions of the
various components and replace if necessary,
and at the intervals indicated in the "PREVENTIVE
MAINTENANCE" table in chapter 11 of the Use and
maintenance manual.
At every valve inspection, replace all O-rings and
all anti-extrusion rings both in the valve units
and on the valve plugs.
Before repositioning the valve unit, thoroughly clean
and dry the relative seats in the head as shown in
Fig. 18.
Fig. 16/a
19
code 26019400
code 27513700
Fig. 16/b
Fig. 17