Wilo -Atmos BST Instrucciones De Instalación Y Funcionamiento página 45

7.4.4 Connection of the pipes
r 2,5 · (d - 2s)
5 x DN
Fig. 4: Settling section upstream and down-
stream of the pump
7.4.5 Final check
8 Electrical connection
Installation and operating instructions • Wilo-Atmos BST • Ed.01/2023-07
Fig. 3: Compensation equation
Σ F and Σ M are the arithmetic sums of the effective values of both pump flanges
effective effective
(inlet and outlet). Σ F
max. permitted
mitted values of both pump flanges (inlet and outlet). The algebraic signs of Σ F and Σ M are
not considered in the compensation equation.
CAUTION
Risk of damage due to incorrect handling!
The pump may never be used as a fixed point for the pipe.
• The present NPSH of the system always has to be greater than the required NPSH of the
pump.
• The forces and torques being exerted by the pipeline system on the pump flange (e.g., by
warping, thermal expansion) may not exceed the permitted 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.
• Minimum axial distance between a wall and the fan cover of the motor: free removal di-
mension of at least 250 mm + ø of the fan cover.
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 discharge ports of the pump before attach-
ing the piping.
• Tighten the foundation bolts if necessary.
• Check all connections for correctness and function.
• It must be possible to turn the pump shaft by hand.
• Electrical work: a qualified electrician must carry out the electrical work.
NOTICE
Nationally applicable guidelines, standards and regulations as well as the
requirements of local energy supply companies must be observed!
CAUTION
Risk of material damage caused by improper electrical connec-
tion!
• Ensure that the current type and voltage of the mains connection cor-
respond to the specifications on the motor rating plate.
and Σ M are the arithmetic sums of the maximum per-
max. permitted
en
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