Wilo Stratos GIGA Einbau- Und Betriebsanleitung Seite 112

en
Connection of the pipes
r ≈ 2,5 * (d-2s)
5 x DN
Fig. 18: Settling section upstream and down-
stream of the pump
Final check
112
CAUTION
Risk of damage due to incorrect handling!
The pump may never be used as a fixed point for the pipe.
NOTICE
Avoid flow cavitation!
• A settling section must be provided upstream and downstream of the
pump in the form of a straight pipe. The length of the settling section
must be at least 5 times the nominal diameter of the pump flange.
• Remove the flange covers at the suction and pressure ports of the pump before attaching
the piping.
• The present NPSH of the system always has to be greater than the required NPSH of the
pump.
• The forces and torques exerted by the piping system on the pump flanges (e.g. due to
torsion, thermal expansion) must not exceed the permissible forces and torques.
• The pipes and pump must be free of mechanical stress when installed.
• The pipes must be fixed in such a way that the pump does not have to support the weight
of the pipes.
• The suction line is to be kept as short as possible. Lay the suction line to the pump so that
it continuously rises while the inlet falls. Avoid possible air entry points.
• If a dirt trap in the suction line is required, its free cross-section has to be 3 – 4 times the
cross-section of the pipe.
• For short pipes, the nominal diameters must be at least those of the pump connections.
For long pipes, determine the most economical nominal diameter in each case.
• To avoid higher pressure losses, make adapters for larger nominal diameters with an ex-
tension angle of approx. 8.
• Leakages at the clamping ring screw connection may be due to transport (e.g. settling be-
haviour) and handling of the pump (rotating the drive, fitting insulation). Further turning
the clamping ring screw connection by a 1/4 turn resolves the leakage.
Fig. 19: Further turning the clamping ring screw connection by a 1/4 turn
Check the alignment of the unit again according to the chapter "Installation".
• Tighten the foundation bolts if necessary.
• Check all connections for correctness and function.
• It must be possible to turn the coupling/shaft by hand.
Do not allow the coupling/shaft to turn:
• Release the coupling and re-tighten with the prescribed torque.
In case this measure is not successful:
• Remove the motor (see chapter "Changing the motor").
• Clean the motor centring and flange.
• Reinstall the motor.
Installation and operating instructions • Wilo-Stratos GIGA, Wilo-Stratos GIGA B • Ed.01/2023-05