Interpump 71 Series - Outlet Line; Calculation of the Internal Diameter of the Duct Pipes

ENGLISH
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The lter must be installed as close as possible to the pump,
it must be easily inspected and must have the following
characteristics:
1. Minimum ow rate at least 3 times the nominal ow rate
of the pump.
2. Inlet/outlet port diameters no smaller than the inlet port
diameter of the pump.
3. Filtration grade between 200 and 360 µm.
For smooth pump operation, regular lter
cleaning is necessary, planned according to the
actual use of the pump in relation to the quality
of water used and actual clogging conditions.
9.8 Outlet line
For the correct laying of the outlet line, the following
installation rules must be followed:
1. The internal diameter of the pipe must be sucient to
ensure correct uid velocity, see graph in par.9.9.
2. The rst section of the line connected to the pump outlet
must be a exible hose, in order to isolate the vibrations
produced by the pump of the rest of the system.
3. Use high pressure pipes and ttings to ensure high safety
margins in all operating conditions.
4. The outlet line must always be provided with a Max.
pressure valve.
5. Use pressure gauges suitable to withstand pulsating loads
typical of the plunger pumps.
6. During the design stage, keep in mind the line load losses
which result in a drop in pressure during use with respect
to the pressure measured on the pump.
7. For those applications where pulses produced by the
pump on the outlet line may prove harmful or unwanted,
install a pulsation dampener of sucient size.
9.9 Calculation of the internal diameter of the
duct pipes
To determine the internal diameter of the duct, refer to the
following diagram:
Suction duct
With a ow rate of ~74 l/min and a water velocity of 0.5 m/sec.
The graph line joining the two scales meets the central scale
showing the diameters, corresponding to a value of ~55mm.
Outlet duct
With a ow rate of ~74 l/min and a water velocity of 5.5 m/sec.
The graph line joining the two scales meets the central scale
showing the diameters, corresponding to a value of ~19mm.
Optimal speeds:
- Suction: ≤ 0.5 m/sec.
- Outlet: ≤ 5.5 m/sec.
The graph does not take into account pipe
resistance, valves, load loss produced by the length
of the ducts, the viscosity of the liquid pumped or
the temperature itself.
If necessary, contact our Technical or Customer
Service Departments.