Pratissoli KS40i Serie Manuel D'utilisation Et D'entretien page 21

In addition it is possible to position the reduction unit in
4 different positions as per Fig. 6.
The position of the reduction unit can only be
changed by authorized specialized personnel
meticulously following the instructions in the
Repair manual.
9.4 Hydraulic connections
In order to isolate the system from vibrations produced by
the pump, it is advisable to make the first section of the duct
adjacent to the pump (both suction and outlet) with flexible
piping. The suction hose must be sufficiently rigid to prevent
deformation due to the negative pressure exerted by the
action of the pump.
9.5 Pump supply
KS pumps require a minimum positive suction head (NPSH
measured on the head suction flange, indicated in the
following table (obtainable with the booster pump):
KS 40i
NPSH (m)
4.0
r
The booster supply pump must have the following features: at
least twice the flow rate of the plunger pump's rated flow rate
with a sufficient minimum pressure for the required NPSHr
and max 6 bar.
These supply conditions must be observed at all operating
speeds.
The operation of the booster pump must be independent
from that of the plunger pump.
9.7 Filtration
Two filters must be installed on the pump suction line, positioned as indicated in Fig. 7 and Fig. 7/a.
With a manually activated control valve
Inlet
Supply tank
The booster pump must always be started up
before the plunger pump.
It is advisable to install a pressure switch on the
supply line downstream of the filters protecting
the pump.
For any supply conditions other than those specified
above, contact our Technical or Customer Service
Departments.
9.6 Suction line
For smooth operation of the pump, the suction line must have
the following characteristics:
1. Minimum internal diameter as indicated in the graph in
Fig. 6
par. 9.9 and in any case equal to or exceeding that of the
pump head.
Localised restrictions should be avoided along the
piping, as these can cause pressure drops resulting
in cavitation. Avoid 90° elbows, connections with
other piping, restrictions, reverse gradients, inverted
U-curves and Tee connections.
2. The layout must be such as to prevent cavitation
problems.
3. Completely airtight and constructed to ensure a perfectly
hermetic seal through time.
4. Prevent the pump from emptying when it is stopped,
including partial emptying.
5. Do not use 3 or 4-way hydraulic fittings, adapters, swivel
),
r
joints, etc. as they could jeopardise pump performance.
6. Do not install Venturi tubes or injectors for detergent
suction.
7. Avoid use of foot valves or other types of unidirectional
valves.
8. Do not recirculate the by-pass valve drain directly to the
suction line.
9. Provide for proper guards inside the tank to prevent that
water flow from the bypass and the tank supply line can
create vortexes or turbulence near the pump supply pipe
port.
10. Make sure the suction line is thoroughly clean inside
before connecting it to the pump.
1 Filter 1
2 Booster Pump
3 Filter 2
4 Pressure gauge
5 Pressure switch
6 Plunger pump
Bypass
21
7 Pressure gauge
8 Safety valve
9 Accumulator
10 Control valve
Fig. 7