Classes Of Increase; Repairing Hydraulic Parts; Dismantling The Head - Valve Units - Pratissoli MK Serie Manuel De Réparation

2.1.3

Classes of increase

INCREASE TABLE FOR BEND SHAFTS AND CON-ROD HALF-BEARINGS
Recovery classes
(mm)
0.25
0.50
Recovery classes
(mm)
1.00
2.2

REPAIRING HYDRAULIC PARTS

2.2.1 Dismantling the head – valve units
The head needs preventive maintenance as indicated in the
Use and maintenance manual.
Operations are limited to inspection or replacement of valves,
if necessary.
Proceed as follows to remove the valve units:
Unscrew the 8 M16x55 screws of the valve cover (pos. ,
Fig. 78) and remove the cover (pos. , Fig. 79).
Upper Half-Bearing Code
90931100
90931200
INCREASE TABLE FOR PUMP CASING AND PISTON GUIDE
Piston Guide Code
79050543
Fig. 78
Fig. 79
55
Lower Half-Bearing Code
90930100
90930200
Adjustments on the Pump Casing
Ø81 H6 +0.022/0 Ra 0.8 Rt 6
Extract the valve plug with the use of an extractor hammer to
be applied on the M10 hole of the valve plug (pos. , Fig. 80).
Remove the spring (pos. , Fig. 81).
Correction on the shaft pin
diameter
(mm)
Ø92.75 0/-0.03 Ra 0.4 Rt 3.5
Ø92.50 0/-0.03 Ra 0.4 Rt 3.5
housing
(mm)
Fig. 80
Fig. 81